Therapeutic Environment and Informed Consent

It is important to seek informed consent while creating a therapeutic and safe environment during all encounters with clients. You will usually begin by introducing yourself by name and designation so the client knows who you are. Next, explain what you are going to do and always ask permission to touch before beginning vital sign measurement. For example, an appropriate introduction is:

It is also important to ensure the client’s privacy by closing the curtains or the door to the room.

Infection Prevention and Control

Clean hands and clean equipment are essential to infection prevention and control when measuring vital signs. Ensuring cleanliness helps reduce communicable and infectious diseases, particularly health care-associated infections, which are infectious organisms acquired by a client while in hospital. Common infections include clostridium difficile (C. diff), vancomycin-resistant enterococcus (VRE), and methicillin-resistant staphylococcus aureus (MRSA).

Ensuring your hands are clean is the best way to prevent and control infection. Hand hygiene can include cleansing with hand gel (see Figure 1.1) and hand washing. (see Figure 1.2). Use an alcohol-based sanitizer before and after contact with clients. Place gel on your hands and rub all hand surfaces for at least fifteen seconds. When washing hands using soap and water, wet your hands and apply soap. Rub all hand surfaces for about fifteen seconds, then rinse your hands. If the tap is not automatic, then turn it off with a paper towel.

Figure 1.1: Hand gel.

Test Yourself!

While watching the interactive video on applying hand gel, apply your knowledge and critical thinking skills by answering the questions throughout the video. Please note: there is no sound in this video.

Figure 1.2: Hand washing.

Test Yourself!

While watching the interactive video on hand washing, perform the skill along with the student while applying your knowledge and critical thinking skills to answer the questions throughout the video. Please note: there is no sound in this video.

Equipment

Healthcare providers always inspect equipment before use to ensure it is in good working condition. Equipment (e.g., stethoscopes, pulse oximeters) can be cleaned with alcohol-based solutions to disinfect the surfaces. Automated devices should be regularly serviced to ensure accuracy. Biomedical technicians/experts are responsible for preventative maintenance and calibration to optimize functioning.

Click on the hotspots to learn about the following pieces of equipment:

Pain Assessment

A pain assessment is conducted in conjunction with the measurement of vital signs because pain can influence the findings. Pain can activate the sympathetic nervous system and increase pulse, respiration, and blood pressure. Pain is a complex issue, and a comprehensive discussion of pain assessment is beyond the scope of this e-book.

Briefly, because pain is subjective, self-reports are the most effective way to assess pain. The choice of pain assessment tool depends on the client situation: healthcare providers frequently use a numeric rating scale such as “rate your pain on a scale of 0 to 10 with zero being no pain and ten being the very worst pain that you have ever felt.” The response is often recorded on the vital sign record and expanded on in the narrative notes. Another common tool is the PQRSTU mneumonic in which each letter corresponds to a series of questions.

• P – Provocative/Palliative (e.g., What makes the pain worse? What makes the pain better?)
• Q – Quality/Quantity (e.g., Can you describe what the pain feels like? How bad is the pain?)
• R – Region/Radiation (e.g., Where is the pain located? Does it radiate anywhere else?)
• S – Severity (as noted above, rate the pain on a scale of zero to ten)
• T – Timing/Treatment (When did the pain begin? Is it constant? Have you taken anything to help the pain? If so, what?)
• U – Understanding (What do you think is causing the pain?)

Order of Vital Sign Measurement

The order of vital sign measurement is influenced by the client situation. Healthcare providers often place the pulse oximeter probe on a client while proceeding to take pulse, respiration, blood pressure, and temperature. However, in some situations this order is modified and the healthcare provider needs to critically assess the situation to prioritize the vital sign measurement order. For example, with newborns/infants, it is best to proceed from least invasive to most invasive, so it is best to begin with respiration, pulse, oxygen saturation, temperature and if required, blood pressure. In an emergency situation or if a person loses consciousness, it is best to begin with pulse and blood pressure. Generally, it is important to conduct a complete set of vital signs unless otherwise indicated.

Significance of Measurements

Determining the significance of vital sign measurements involves a process of diagnostic reasoning. The healthcare provider analyzes client data and makes decisions about whether the vital signs are normal or abnormal and whether the findings are significant: the following chapters provide normal vital sign ranges. The healthcare provider also considers agency policy, if applicable, about vital sign ranges to assess any abnormal variations and clinical significance. Additionally, the healthcare provider considers the client’s baseline vital signs to obtain a better sense of the client’s ‘normal’ and allow comparison (e.g., of trends) over time. The diagnostic reasoning process also involves considering other available objective and subjective data.

Documentation

Timely documentation of vital sign measurements is imperative as a form of communication, to observe trends in vital sign measurements, and to ensure effective intervention when needed. Documentation occurs on paper-based vital sign records or electronic systems depending on the agency. Healthcare providers follow the agency’s documentation policy and the professional standards of practice. If using a vital sign record, healthcare providers use the symbols noted on the legend of the record.

Test Your Knowledge

Please answer the seven questions in the following question set.

Temperature refers to the degree of heat or cold in an object or a human body. In humans, the brain’s hypothalamus acts as the body’s thermostat and is responsible for regulating its temperature (OER #2). See Figure 2.1 of the hypothalamus.

The human body is constantly adapting to internal health states and environmental conditions, and the hypothalamus is programmed to tell the body to generate heat if the body temperature is low. For example, the hypothalamus can activate peripheral vasoconstriction and shivering (contraction of skeletal muscles) to prevent a decrease in body temperature. The hypothalamus can also reduce heat if the body temperature is too high. For example, it can activate peripheral vasodilation to increase heat loss and cause a person to perspire, which cools the body.

Figure 2.1: Hypothalamus. (Illustration credit: Hilary Tang)

Chapter Attributions

Part of this content was adapted from OER #2 (as noted in brackets above):

• © Apr 10, 2017 OpenStax Anatomy and Physiology. Textbook content produced by OpenStax Anatomy and Physiology is licensed under a Creative Commons Attribution License 4.0 license. Download for free at http://cnx.org/contents/7c42370b-c3ad-48ac-9620-d15367b882c6@12

Healthcare providers measure a client’s temperature because it can give information about their state of health and influence clinical decisions. Accurate measurements and interpretation are vital so that hyperthermia and hypothermia can be identified and appropriate interventions determined.

Hyperthermia refers to an elevated body temperature. It can be related to an internal or external source. External sources that increase body temperature could include exposure to excessive heat on a hot day or being in a sauna or hot tub. Internal sources that may increase body temperature include fever caused by an infection or tissue breakdown associated with physical trauma (e.g., surgery, myocardial infarction) or some neurological conditions (e.g., cerebral vascular accident, cerebral edema, brain tumour). Hyperthermia that is associated with an infectious agent, such as a bacteria or virus (e.g., the flu) is referred to as febrile. Unresolved hyperthermic body states can lead to cell damage.

Hypothermia refers to a lowered body temperature. It is usually related to an external source such as being exposed to the cold for an extended period of time. Hypothermia is sometimes purposefully induced during surgery, or for certain medical conditions, to reduce the body’s need for oxygen. Unresolved hypothermic body states can slow cellular processes and lead to loss of consciousness.

Test Your Knowledge

Methods of measuring a client’s body temperature vary based on developmental age, cognitive functioning, level of consciousness, state of health, safety, and agency/unit policy. The healthcare provider chooses the best method after considering client safety, accuracy, and least invasiveness, all contingent on the client’s health and illness state. The most accurate way to measure core body temperature is an invasive method through a pulmonary artery catheter. This is only performed in a critical care area when constant measurements are required along with other life-saving interventions.

Methods of measurement include oral, axillary, tympanic, rectal, and dermal routes.

Oral temperature can be taken with clients who can follow instructions, so this kind of measurement is common for clients over the age of four, or even younger children if they are cooperative. Another route other than oral (e.g., tympanic or axillary) is preferable when a client is on oxygen delivered via a face mask because this can alter the temperature.

For children younger than four, axillary temperature is commonly measured unless a more accurate reading is required.

Rectal temperature is an accurate way to measure body temperature (Mazerolle, Ganio, Casa, Vingren, & Klau, 2011). The rectal route is recommended by the Canadian Pediatric Society for children under two years of age (Leduc & Woods, 2017). However, this method is not used on infants younger than thirty days or premature infants because of the risk of rectal tearing. If the rectal method is required, the procedure is generally only used by nurses and physicians.

Dermal routes are alternative methods of measurement that may be used in some agencies and practice areas. This method can involve holding the device and sliding it over the skin of the forehead and then down over the temporal artery in one motion. Dermal strips can also be placed on the forehead to measure skin temperature, but are not yet widely used, and the accuracy of this method has not yet been verified. More recently, there has been an increase in non-contact infrared thermometers particularly in the era of COVID-19 and other highly transmissible diseases. Depending on the type, these thermometers can be held at a short distance from the forehead or temporal area to measure temperature. Alternatively, some handheld thermal scanners that use an infrared camera can be held at a greater distance to screen large masses of people. Please refer to the manufacturer’s suggested reference range for non-contact infrared thermometers and thermal scanners.

Test Yourself!

While watching the interactive video on measuring temperature with a non-contact infrared thermometer, apply your knowledge and critical thinking skills to answer the questions throughout the video. Please note: there is no sound in this video.

The following pages detail the normal temperature ranges and techniques associated with oral, axillary, tympanic, and rectal temperature methods.

The human body’s core temperature (internal body temperature) is measured in degrees Celsius (ºC) or Fahrenheit (ºF). In Canada, degrees Celsius is most commonly used.

In adults, the normal core body temperature (referred to as normothermia or afebrile) is 36.5–37.5ºC or 97.7–99.5ºF (OER #2).

A wider temperature range is acceptable in infants and young children, and can range from 35.5–37.7ºC or 95.9–99.8ºF. Infants and children have a wider temperature range because their heat control mechanisms are less effective. They are at risk for heat loss for many reasons including having less subcutaneous fat than adults, a larger body surface area in comparison to weight (and larger head size in proportion to the rest of the body), immature metabolic mechanisms (e.g., they may be unable to shiver), and limited ability to produce heat through activity. They are also at risk of excessive heat production due to crying and restlessness as well as external factors such as being wrapped in too many blankets.

Older adults tend to have lower body temperatures and are at risk for hypothermic states; reasons for this may include having less subcutaneous tissue acting as insulation, loss of peripheral vasoconstriction capacity, decreased cardiac output with resultant lowered blood flow to the extremities, decreased muscle mass resulting in reduced heat production capacity, and decreased metabolic responses.

See Table 2.1 for normal temperature ranges based on method. The normal ranges vary slightly for each of the methods. It is important to consider a client’s baseline temperature as some individuals present with a temperature slightly above or below these ranges. To make an informed clinical judgement, examine the client’s records to determine a trend in temperature. A pattern of high or low temperature findings may reveal a baseline for your client. As a healthcare provider, it is important to determine the significance of the temperature by also considering influencing factors and the client’s overall state of health.

Other factors that influence temperature include diurnal rhythm, exercise, stress, menstrual cycle, and pregnancy. The diurnal cycle causes a fluctuation of 1ºC, with temperatures lowest in the early morning and highest in the late afternoon. During exercise, body temperature rises because the body is using energy to power the muscles. Temperature can rise as a result of stress and anxiety, due to stimulation of the sympathetic nervous system and increased secretion of epinephrine and norepinephrine. Body temperature varies throughout a woman’s menstrual cycle due to hormonal fluctuations, rising after ovulation until menstruation by about 0.5–1ºC. Body temperature is slightly elevated during pregnancy as a result of increased metabolism and hormone production such as progesterone.

Test Your Knowledge

Chapter Attributions

Part of this content was adapted from OER #2 (as noted in brackets above):

• © Apr 10, 2017 OpenStax Anatomy and Physiology. Textbook content produced by OpenStax Anatomy and Physiology is licensed under a Creative Commons Attribution License 4.0 license. Download for free at http://cnx.org/contents/7c42370b-c3ad-48ac-9620-d15367b882c6@12

The normal oral temperature is 35.8–37.3ºC (OER #1) or 96.4–99.1ºF. Oral temperature measurement is common and reliable because it is close to the sublingual artery. An oral thermometer is shown in Figure 2.2. The device has blue colouring, indicating that it is an oral or axillary thermometer as opposed to a rectal thermometer, which has red colouring.

Figure 2.2: Oral thermometer.

Technique

Remove the probe from the device and place a probe cover (from the box) on the oral thermometer without touching the probe cover with your hands. Place the thermometer in the client’s mouth under the tongue and instruct client to keep mouth closed and not to bite on the thermometer (OER #1). Ensure the thermometer probe is in the posterior sublingual pocket under the tongue, slightly off-centre. Leave the thermometer in place for as long as is indicated by the device manufacturer (OER #1). The thermometer will beep within a few seconds when the temperature has been taken: most oral thermometers are electronic and provide a digital display of the reading. Discard the probe cover in the garbage (without touching the cover) and place the probe back into the device. See Figure 2.3 of an oral temperature being taken.

Figure 2.3: Oral temperature being taken.

What should the healthcare provider consider?

Healthcare providers often measure the oral temperature, particularly when the client is conscious and can follow directions. Measurement of the oral temperature is not recommended for individuals who are unconscious, unresponsive, confused, have an endotracheal tube secured in the mouth, and cannot follow instructions.

Certain factors render the oral route less accurate with the potential for falsely high or falsely low findings. If the client has recently consumed hot or cold food or beverage, chewing gum, or has smoked prior to measurement, the healthcare provider should use another route such as tympanic or axillary. Selecting an alternate route under the aforementioned circumstances is most conducive to a fast-paced clinical environment and most respectful of the client’s time. If another route is not available, healthcare providers should wait 15 to 25 minutes to take the oral temperature following consumption of a hot or cold beverage/food. The temperature of the beverage/food also factors into the wait period, as extreme heat or cold will require longer wait times for oral temperature assessment. Healthcare providers should wait about 5 minutes if the client is chewing gum or has just smoked since both of these activities can increase temperature.

Test Yourself!

While watching the interactive video on measuring temperature with an oral thermometer, apply your knowledge and critical thinking skills to answer the questions throughout the video. Please note: there is no sound in this video.

Test Your Knowledge

Please answer the three questions in the following question set.

Chapter Attributions

Part of this content was adapted from OER #1 (as noted in brackets above):

• © 2015 British Columbia Institute of Technology (BCIT). Clinical Procedures for Safer Patient Care by Glynda Rees Doyle and Jodie Anita McCutcheon, British Columbia Institute of Technology. Licensed under a Creative Commons Attribution 4.0 International License, except where otherwise noted. Download this book for free at http://open.bccampus.ca

The normal tympanic temperature is usually 0.3–0.6°C higher than an oral temperature (OER #1). It is accurate because the tympanic membrane shares the same vascular artery that perfuses the hypothalamus (OER #1). A tympanic thermometer is shown in Figure 2.4.

Figure 2.4: Tympanic thermometer.

Technique

Remove the tympanic thermometer from the casing and place a probe cover (from the box) on the thermometer tip without touching the probe cover with your hands. Only touch the edge of the probe cover (if needed), to maintain clean technique. Turn the device on. Ask the client to keep head still. For an adult or older child, gently pull the helix up and back to visualize the ear canal. For an infant or younger child (under 3), gently pull the lobe down. The probe is inserted just inside the opening of the ear. Never force the thermometer into the ear and do not occlude the ear canal (OER #1). Only the tip of the probe is inserted in the opening – this is important to prevent damage to the ear canal. Activate the device; it will beep within a few seconds to signal it is done. Discard the probe cover in the garbage (without touching the cover) and place the device back into the holder. See Figure 2.5 of a tympanic temperature being taken.

Figure 2.5: Tympanic temperature being taken.

What should the healthcare provider consider?

The tympanic temperature method is a quick and minimally invasive way to take temperature. Although research has proven the accuracy of this method, some pediatric institutions prefer the accuracy of the rectal temperature. The Canadian Pediatric Society found equal evidence for and against the use of tympanic temperature route (Leduc & Woods, 2017). It concluded that tympanic temperature is one option for use with children, but suggested using rectal temperature for children younger than two, particularly when accuracy is vital. The tympanic temperature is not measured when a client has a suspected ear infection. It is important to check your agency policy regarding tympanic temperature.

Test Yourself!

While watching the interactive video on measuring temperature with a tympanic thermometer, apply your knowledge and critical thinking skills to answer the questions throughout the video. Please note: there is no sound in this video.

Test Your Knowledge

Chapter Attributions

Part of this content was adapted from OER #1 (as noted in brackets above):

• © 2015 British Columbia Institute of Technology (BCIT). Clinical Procedures for Safer Patient Care by Glynda Rees Doyle and Jodie Anita McCutcheon, British Columbia Institute of Technology. Licensed under a Creative Commons Attribution 4.0 International License, except where otherwise noted. Download this book for free at http://open.bccampus.ca

The normal axillary temperature may be as much as 1ºC lower than the oral temperature (OER #1). An axillary thermometer is the same electronic device as an oral thermometer, and both have a blue end.

Technique

Remove the probe from the device and place a probe cover (from the box) on the thermometer without touching the cover with your hands. Ask the client to raise the arm away from his/her body. Place the thermometer in the client’s armpit (OER #1), on bare skin, as high up into the axilla as possible, with the point facing behind the client. Ask the client to lower his/her arm and leave the device in place for as long as is indicated by the device manufacturer (OER #1). Usually the device beeps in 10–20 seconds. Discard the probe cover in the garbage (without touching the cover) and place the probe back into the device. See Figure 2.6 of an axillary temperature being taken.

Figure 2.6: Axillary temperature being taken.

What should the healthcare provider consider?

The axillary route is a minimally invasive way to measure temperature. It is commonly used in children. It is important to ensure that the thermometer is as high up in the axilla as possible with full skin contact and that the client’s arm is then lowered down.

Test Yourself!

While watching the interactive video on measuring temperature with an axillary thermometer, apply your knowledge and critical thinking skills to answer the questions throughout the video. Please note: there is no sound in this video.

_________________________________________________________________________

Chapter Attributions

Part of this content was adapted from OER #1 (as noted in brackets above):

• © 2015 British Columbia Institute of Technology (BCIT). Clinical Procedures for Safer Patient Care by Glynda Rees Doyle and Jodie Anita McCutcheon, British Columbia Institute of Technology. Licensed under a Creative Commons Attribution 4.0 International License, except where otherwise noted. Download this book for free at http://open.bccampus.ca

The normal rectal temperature is usually 1ºC higher than oral temperature (OER #1). A rectal thermometer has a red end to distinguish it from an oral/axillary thermometer. A rectal thermometer is shown in Figure 2.7.

Figure 2.7: Rectal thermometer.

Technique

First, ensure the client’s privacy. Wash your hands and put on gloves. For infants, lie them down in a supine position and raise their legs up toward the chest. You can encourage a parent to hold the infant to decrease movement and provide a sense of safety. With older children and adults, assist them into a side lying position. Remove the probe from the device and place a probe cover (from the box) on the thermometer. Lubricate the cover with a water-based lubricant, and then gently insert the probe 2–3 cm inside the rectal opening of an adult, or less depending on the size of the client. The device beeps when it is done.

What should the healthcare provider consider?

Measuring rectal temperature is an invasive method. Some suggest its use only when other methods are not available (OER #1), while others suggest that the rectal route is a gold standard in the infant population because of its accuracy. The Canadian Pediatric Society (Leduc & Woods, 2017) has referred to research indicating that rectal temperatures may remain elevated after a client’s core temperature has started to return to normal, but after reviewing all available evidence, still recommends measuring rectal temperature for children under the age of two, particularly when accuracy is vital. Rectal temperature is not measured in infants under one month of age or premature newborns.

Test Your Knowledge

Please answer the four questions in the following question set.

Chapter Attributions

Part of this content was adapted from OER #1 (as noted in brackets above):

• © 2015 British Columbia Institute of Technology (BCIT). Clinical Procedures for Safer Patient Care by Glynda Rees Doyle and Jodie Anita McCutcheon, British Columbia Institute of Technology. Licensed under a Creative Commons Attribution 4.0 International License, except where otherwise noted. Download this book for free at http://open.bccampus.ca

Which is the correct technique for measuring the tympanic temperature?

Next, there are three activities that involve film clips that you can watch and then try out yourself. You can watch the clips and practice as many times as you like.

Oral Temperature

Watch this short film clip 2.1 and see how oral temperature is taken correctly. After watching the clip, try the technique yourself.

Film clip 2.1: Oral temperature

A YouTube element has been excluded from this version of the text. You can view it online here: https://opentextbc.ca/vitalsignmeasurement/?p=56

Alternatively, if viewing textbook as a PDF, use this link: https://www.youtube.com/embed/HVpjXk0B6SA?rel=0

Tympanic Temperature

Watch this short film clip 2.2 and see how tympanic temperature is taken correctly. After watching the clip, try the technique yourself.

Film clip 2.2: Tympanic temperature

A YouTube element has been excluded from this version of the text. You can view it online here: https://opentextbc.ca/vitalsignmeasurement/?p=56

Alternatively, if viewing textbook as a PDF, use this link: https://www.youtube.com/embed/cVusEmUWTC8?rel=0

Axilla Temperature

Watch this short film clip 2.3 and see how axilla temperature is taken correctly. After watching the clip, try the technique yourself.

Film clip 2.3: Axilla temperature

A YouTube element has been excluded from this version of the text. You can view it online here: https://opentextbc.ca/vitalsignmeasurement/?p=56

Alternatively, if viewing textbook as a PDF, use this link: https://www.youtube.com/embed/m71ISuIJRlA?rel=0

Multiple Choice

List the Steps

List the steps below in the correct order for each of the following techniques.

Temperature is an important vital sign because it provides current data about the client’s health and illness state. Changes in body temperature act as a cue for healthcare providers’ diagnostic reasoning.

There are many ways to measure temperature. In determining the best method, the healthcare provider considers agency policy, the client’s age and health and illness state, and the reason for taking the temperature. Healthcare providers must use the correct technique when measuring temperature, because this can influence client data.

When determining the relevance of the temperature, the healthcare provider considers the client’s baseline data and the situation. Diagnostic reasoning about temperature always involves considering additional data including other vital sign measurements and subjective and objective client data.

Pulse refers to a pressure wave that expands and recoils the artery when the heart contracts/beats. It is palpated at many points throughout the body. The most common locations to accurately assess pulse as part of vital sign measurement include radial, brachial, carotid, and apical pulse as shown in Figure 3.1. The techniques vary according to the location, as detailed later.

Figure 3.1: Radial, brachial, carotid and apical pulse. (Illustration credit: Hilary Tang)

The heart pumps a volume of blood per contraction into the aorta. This volume is referred to as stroke volume. Age is one factor that influences stroke volume, which ranges from 5–80 mL from newborns to older adults.

Pulse is measured in beats per minute, and the normal adult pulse rate (heart rate) at rest is 60–100 beats per minute (OER #1, OER #2). Newborn resting heart rates range from 100–175 bpm. Heart rate gradually decreases until young adulthood and then gradually increases again with age (OER #2). A pregnant women’s heart rate is slightly higher than her pre-pregnant value (about 15 beats). See Table 3.1 for normal heart rate ranges based on age.

Please answer the two questions in the following question set.

Chapter Attributions

• Part of this content was adapted from OER #1 (as noted in brackets above): © 2015 British Columbia Institute of Technology (BCIT). Clinical Procedures for Safer Patient Care by Glynda Rees Doyle and Jodie Anita McCutcheon, British Columbia Institute of Technology. Licensed under a Creative Commons Attribution 4.0 International License, except where otherwise noted. Download this book for free at http://open.bccampus.ca
• Part of this content was adapted from OER #2 (as noted in brackets above): © Apr 10, 2017 OpenStax Anatomy and Physiology. Textbook content produced by OpenStax Anatomy and Physiology is licensed under a Creative Commons Attribution License 4.0 license. Download for free at http://cnx.org/contents/7c42370b-c3ad-48ac-9620-d15367b882c6@12

Healthcare providers measure pulse because it provides information about a client’s state of health and influences diagnostic reasoning and clinical decision-making.

Tachycardia

Tachycardia refers to an elevated heart rate, typically above 100 bpm (OER #2) for an adult. Developmental considerations are important to consider, such as higher resting pulse rates in infants and children. For adults, tachycardia is not normal in a resting state but may be detected in pregnant women or individuals experiencing extreme stress (OER #2). Tachycardia can be benign, such as when the sympathetic nervous system is activated with exercise and stress. Caffeine intake and nicotine can also elevate the heart rate. Tachycardia is also correlated with fever, anemia, hypoxia, hyperthyroidism, hypersecretion of catecholamines, some cardiomyopathies, some disorders of the valves, and acute exposure to radiation (OER #2).

Bradycardia

Bradycardia is a condition in which the resting heart rate drops below 60 bpm (OER #2) in adults. In newborns, a resting heart rate below 100 bpm is considered bradycardia. However, a sleeping neonate’s pulse may be as low as 90 bpm. People who are physically fit (e.g., trained athletes) typically have lower heart rates (OER #2). If the client is not exhibiting other symptoms, such as weakness, fatigue, dizziness, fainting, chest discomfort, palpitations, or respiratory distress, bradycardia is generally not considered clinically significant (OER #2). However, if any of these symptoms are present, this may indicate that the heart is not providing sufficient oxygenated blood to the tissues (OER #2). Bradycardia can be related to an electrical issue of the heart, ischemia, metabolic disorders, pathologies of the endocrine system, electrolyte imbalances, neurological disorders, prescription medications, and prolonged bedrest, among other conditions (OER #2). Bradycardia is also related to some medications, such as beta blockers and digoxin.

Chapter Attributions

Part of this content was adapted from OER #2 (as noted in brackets above):

• © Apr 10, 2017 OpenStax Anatomy and Physiology. Textbook content produced by OpenStax Anatomy and Physiology is licensed under a Creative Commons Attribution License 4.0 license. Download for free at http://cnx.org/contents/7c42370b-c3ad-48ac-9620-d15367b882c6@12

The pulse rhythm, rate, force, and equality are assessed when palpating pulses.

Pulse Rhythm

The normal pulse rhythm is regular, meaning that the frequency of the pulsation felt by your fingers follows an even tempo with equal intervals between pulsations. If you compare this to music, it involves a constant beat that does not speed up or slow down, but stays at the same tempo. Thus, the interval between pulsations is the same. However, sinus arrhythmia is a common condition in children, adolescents, and young adults. Sinus arrhythmia involves an irregular pulse rhythm in which the pulse rate varies with the respiratory cycle: the heart rate increases at inspiration and decreases back to normal upon expiration. The underlying physiology of sinus arrhythmia is that the heart rate increases to compensate for the decreased stroke volume from the heart’s left side upon inspiration.

Pulse Rate

The pulse rate is counted by starting at one, which correlates with the first beat felt by your fingers. Count for thirty seconds if the rhythm is regular (even tempo) and multiply by two to report in beats per minute. Count for one minute if the rhythm is irregular. In children, pulse is counted for one minute considering that irregularities in rhythm are common.

Pulse Force

The pulse force is the strength of the pulsation felt when palpating the pulse. For example, when you feel a client’s pulse against your fingers, is it gentle? Can you barely feel it? Alternatively, is the pulsation very forceful and bounding into your fingertips? The force is important to assess because it reflects the volume of blood, the heart’s functioning and cardiac output, and the arteries’ elastic properties. Remember, stroke volume refers to the volume of blood pumped with each contraction of the heart (i.e., each heart beat). Thus, pulse force provides an idea of how hard the heart has to work to pump blood out of the heart and through the circulatory system.

Pulse force is recorded using a four-point scale:

• 3+ Full, bounding
• 2+ Normal/strong
• 1+ Weak, diminished, thready
• 0 Absent/non-palpable

Practice on many people to become skilled in measuring pulse force. While learning, it is helpful to assess pulse force along with an expert because there is a subjective element to the scale. A 1+ force (weak and thready) may reflect a decreased stroke volume and can be associated with conditions such as heart failure, heat exhaustion, or hemorrhagic shock, among other conditions. A 3+ force (full and bounding) may reflect an increased stroke volume and can be associated with exercise and stress, as well as abnormal health states including fluid overload and high blood pressure.

Pulse Equality

Pulse equality refers to whether the pulse force is comparable on both sides of the body. For example, palpate the radial pulse on the right and left wrist at the same time and compare whether the pulse force is equal. Pulse equality is assessed because it provides data about conditions such as arterial obstructions and aortic coarctation. However, the carotid pulses should never be palpated at the same time as this can decrease and/or compromise cerebral blood flow.

These are the upper body pulse points that will be covered in the following sections.

Technique

Use the pads of your first three fingers to gently palpate the radial pulse (OER #1). The pads of the fingers are placed along the radius bone, which is on the lateral side of the wrist (the thumb side; the bone on the other side of the wrist is the ulnar bone). Place your fingers on the radius bone close to the flexor aspect of the wrist, where the wrist meets the hand and bends. See Figure 3.2 for correct placement of fingers. Press down with your fingers until you can best feel the pulsation. Note the rate, rhythm, force, and equality when measuring the radial pulse (OER #1).

Figure 3.2: Correct placement of fingers.

Test Yourself!

While watching the interactive video on pulse and respiration measurement, apply your knowledge and critical thinking skills to answer the questions throughout the video.

This video is also at the end of the chapter, uninterrupted, to enable seamless practice.

What should the healthcare provider consider?

You may need to adjust the pressure of your fingers when palpating the radial pulse if you cannot feel the pulse. For example, sometimes pressing too hard can obliterate the pulse (make it disappear). Alternatively, if you do not press hard enough, you may not feel a pulse. You may also need to move your fingers around slightly. Radial pulses are difficult to palpate on newborns and children under five, so healthcare providers usually assess the apical pulse or brachial pulse of newborns and children.

A YouTube element has been excluded from this version of the text. You can view it online here: https://opentextbc.ca/vitalsignmeasurement/?p=77

Film clip 3.1: Use of doppler device

Alternatively, if viewing textbook as a PDF, use this link: https://www.youtube.com/embed/cn3aA0G1mgc?rel=0

Chapter Attributions

Part of this content was adapted from OER #1 (as noted in brackets above):

• © 2015 British Columbia Institute of Technology (BCIT). Clinical Procedures for Safer Patient Care by Glynda Rees Doyle and Jodie Anita McCutcheon, British Columbia Institute of Technology. Licensed under a Creative Commons Attribution 4.0 International License, except where otherwise noted. Download this book for free at http://open.bccampus.ca

May be taken when radial pulse is not present or is difficult to palpate (OER #1).

Technique

Ask the client to sit upright. Locate the carotid artery medial to the sternomastoid muscle (between the muscle and the trachea at the level of the cricoid cartilage, which is in the middle third of the neck). With the pads of your three fingers, gently palpate the carotid artery, one at a time. See Figure 3.3 for correct placement of fingers.

Figure 3.3: Correct placement of fingers.

What should the healthcare provider consider?

Although other pulses can be taken simultaneously to assess equality, the carotid pulses are NEVER taken at the same time. Gently palpate one artery at a time so that you do not stimulate the vagus nerve and compromise arterial blood flow to the brain. Avoid palpating the upper third of the neck, because this is where the carotid sinus area is located. You want to avoid pressure on the carotid sinus area because this can lead to vagal stimulation, which can slow the heart rate, particularly in older adults.

Chapter Attributions

Part of this content was adapted from OER #1 (as noted in brackets above):

• © 2015 British Columbia Institute of Technology (BCIT). Clinical Procedures for Safer Patient Care by Glynda Rees Doyle and Jodie Anita McCutcheon, British Columbia Institute of Technology. Licensed under a Creative Commons Attribution 4.0 International License, except where otherwise noted. Download this book for free at http://open.bccampus.ca

Brachial pulse rate is indicated during some assessments, such as with children, in whom it can be difficult to feel the radial pulse. A Doppler can be used to locate the brachial pulse if needed.

Technique

The brachial pulse can be located by feeling the bicep tendon in the area of the antecubital fossa. Move the pads of your three fingers medial (about 2 cm) from the tendon and about 2–3 cm above the antecubital fossa to locate the pulse. See Figure 3.4 for correct placement of fingers along the brachial artery.

Figure 3.4: Correct placement of fingers.

What should the healthcare provider consider?

It can be helpful to hyper-extend the arm in order to accentuate the brachial pulse so that you can better feel it. You may need to move your fingers around slightly to locate the best place to most accurately feel the pulse. You will usually need to press fairly firmly to palpate the brachial pulse.

Apical pulse is auscultated with a stethoscope over the chest where the heart’s mitral valve is best heard. In infants and young children, the apical pulse is located at the fourth intercostal space at the left midclavicular line. In adults, the apical pulse is located at the fifth intercostal space at the left midclavicular line (OER #1). See Figure 3.5 below.

Figure 3.5: Apical Pulse. (Illustration credit: Hilary Tang)

Apical pulse rate is indicated during some assessments, such as when conducting a cardiovascular assessment and when a client is taking certain cardiac medications (e.g., digoxin) (OER #1). Sometime the apical pulse is auscultated pre and post medication administration. It is also a best practice to assess apical pulse in infants and children up to five years of age because radial pulses are difficult to palpate and count in this population. It is typical to assess apical pulses in children younger than eighteen, particularly in hospital environments. Apical pulses may also be taken in obese people, because their peripheral pulses are sometimes difficult to palpate.

Technique

Position the client in a supine (lying flat) or in a seated position. Physically palpate the intercostal spaces to locate the landmark of the apical pulse. Ask the female client to re-position her own breast tissue to auscultate the apical pulse. For example, the client gently shifts the breast laterally so that the apical pulse landmark is exposed. Alternatively, the healthcare provider can use the ulnar side of the hand to re-position the breast tissue and auscultate the apical pulse. Ensure draping to protect the client’s privacy.

Either the bell or diaphragm are used to auscultate the client’s heart rate and rhythm. There is a pediatric-size stethoscope for infants. Typically, apical pulse rate is taken for a full minute to ensure accuracy; this is particularly important in infants and children due to the possible presence of sinus arrhythmia. In adults, if you are assessing the apical pulse due to an irregular rhythm then count for one minute. Upon auscultating the apical pulse, you will hear the sounds “lub dup” – this counts as one beat. Continue counting the apical pulse and note the rate and rhythm.

Listen to Audio clip 3.1 and count the apical pulse. For practice, we have made this clip 30 seconds so you will need to multiply it by two to report it as beats per minute (but remember, the most accurate measurement is to count the apical pulse for one minute).

Audio clip 3.1: Counting apical pulse rate  

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What should the healthcare provider consider?

Although pulses are best measured at rest, sometimes this is not possible. It is important to document other factors such as when a person is in pain or an infant/child is crying.

Pulse Check! Test Your Knowledge

Now, you find the four pulse points.

Please answer the seven questions in the following question set.

Chapter Attributions

Part of this content was adapted from OER #1 (as noted in brackets above):

• © 2015 British Columbia Institute of Technology (BCIT). Clinical Procedures for Safer Patient Care by Glynda Rees Doyle and Jodie Anita McCutcheon, British Columbia Institute of Technology. Licensed under a Creative Commons Attribution 4.0 International License, except where otherwise noted. Download this book for free at http://open.bccampus.ca

Respiration refers to a person’s breathing and the movement of air into and out of the lungs (OER #2). The respiratory system provides oxygen to body tissues for cellular respiration, removes the waste product carbon dioxide, and helps maintain acid–base balance (OER #2). Inspiration is the process that causes air to enter the lungs, and expiration is the process that causes air to leave the lungs (OER #2). A respiratory cycle (or one breath while you are measuring respiratory rate) is one sequence of inspiration and expiration (OER #2).

Respiration is assessed for quality, rhythm, and rate.

The quality of a person’s breathing is normally relaxed and silent. Healthcare providers assess use of accessory muscles in the neck and chest and indrawing of intercostal spaces (also referred to as intercostal tugging), which can indicate respiratory distress. Respiratory distress can also cause nasal flaring, and the person often moves into a tripod position. The tripod position involves leaning forward and placing arms/hands and/or upper body on one’s knees or on the bedside table.

Respiration normally has a regular rhythm. A regular rhythm means that the frequency of the respiration follows an even tempo with equal intervals between each respiration. If you compare this to music, it involves a constant beat that does not speed up or slow down, but stays at the same tempo.

Respiratory rates vary based on age. The normal resting respiratory rate for adults is 10–20 breaths per minute (OER #1). Children younger than one year normally have a respiratory rate of 30–60 breaths per minute, but by the age of ten, the normal rate is usually 18–30 (OER #2). By adolescence, the respiratory rate is usually similar to that of adults, 12–18 breaths per minute (OER #2). The normal respiratory rate for children decreases from birth to adolescence (OER #2). Respiratory rates often increase slightly over the age of sixty-five.

Estimated respiratory rates vary based on the source. Table 3.2 lists a generous range of normal respiratory rates based on age. It is important to consider the client and the situation to determine whether the respiratory rate is normal. Healthcare providers take into consideration the client’s health and illness state and determinants such as rest/sleep, awake/active, presence of pain, and crying when assessing the respiratory rate.

Chapter Attributions

Part of this content was adapted from OER #1 (as noted in brackets above):

• © 2015 British Columbia Institute of Technology (BCIT). Clinical Procedures for Safer Patient Care by Glynda Rees Doyle and Jodie Anita McCutcheon, British Columbia Institute of Technology. Licensed under a Creative Commons Attribution 4.0 International License, except where otherwise noted. Download this book for free at http://open.bccampus.ca

Part of this content was adapted from OER #2 (as noted in brackets above):

• © Apr 10, 2017 OpenStax Anatomy and Physiology. Textbook content produced by OpenStax Anatomy and Physiology is licensed under a Creative Commons Attribution License 4.0 license. Download for free at http://cnx.org/contents/7c42370b-c3ad-48ac-9620-d15367b882c6@12

Technique

The respiratory rate is counted after taking the pulse rate so that the client is not aware that you are taking it (OER #1). Once you have finished counting the pulse, leave your fingers in place and then begin assessing respiration. Observe the chest or abdomen rise and fall. One respiration includes a full respiratory cycle (including both inspiration and expiration). Thus, the rise and the fall of the abdomen or chest is counted as one full breath. Count for 30 seconds if the rhythm is regular or for a full minute if irregular (OER #1). Report the respiration as breaths per minute, as well as whether breathing is relaxed, silent, and has a regular rhythm. Report whether chest movement is symmetrical.

What should the healthcare provider consider?

Assess the movement of the chest with adults, and the movement of the abdomen with newborns and infants. Adults are normally thoracic breathers (the chest moves) while infants are normally diaphragmatic breathers (the abdomen moves). Some adults are abdominal breathers. Breathing rates are counted for one minute with infants because the respiratory rhythm (tempo) can vary significantly. For example, the breathing rates of infants can speed up and slow down with some short periods of apnea (pauses in breathing).

When assessing respiration, ensure that thick and bulky clothing is removed so you can clearly see the rise and fall of the chest or abdomen. Although respiratory rates are best counted at rest, sometimes this is not possible (e.g., in an emergency situation and with a child who is crying). In this case, document the situation. While assessing respirations, it is important to note signs of respiratory distress, which can include loud breathing, nasal flaring, and intercostal retractions. See Figure 3.7 for signs of respiratory distress. These signs require further assessment and intervention.

Figure 3.7: Signs of respiratory distress. (Illustration credit: Paige Jones)

Test Your Knowledge

Now, you try it!

Please answer the three questions in the following question set.

Chapter Attributions

Part of this content was adapted from OER #1 (as noted in brackets above):

• © 2015 British Columbia Institute of Technology (BCIT). Clinical Procedures for Safer Patient Care by Glynda Rees Doyle and Jodie Anita McCutcheon, British Columbia Institute of Technology. Licensed under a Creative Commons Attribution 4.0 International License, except where otherwise noted. Download this book for free at http://open.bccampus.ca

Radial Pulse

Which is the correct technique for measuring the radial pulse?

Infant Apical Pulse

Which image shows the correct method for measuring the apical pulse on a toddler?

Adult Apical Pulse

Which image shows the correct method for measuring the apical pulse on an adult?

Next, there are two activities that involve two film clips that you can watch and then try out yourself. You can watch the clips and practice as many times as you like.

Radial Pulse and Respiration

Watch this short film clip 3.2 and see how to measure radial pulse and respiration correctly. After watching the clip, try the technique yourself.

Film clip 3.2: Pulse and respiration measurement

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Apical Pulse

Watch this short film clip 3.3 and see how to measure an apical pulse correctly. After watching the clip, try the technique yourself.

Film clip 3.3: Correct measurement of apical pulse

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Now that you have completed this chapter, it’s time to test your knowledge. Try to answer the following questions (you may want to review parts of the chapter before answering).

Pulse

What is the apical pulse rate?

Listen to the audio clip of the apical pulse. Count the pulse for 30 seconds and report the rate as beats per minute. (NOTE: Although this clip only allows you to count for 30 seconds, remember, it is best to count the apical pulse for one minute.)

Audio clip 3.2: Apical pulse

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What is the apical pulse rate?

Listen to the audio clip of the apical pulse. Count the pulse for 30 seconds and report the rate as beats per minute. (NOTE: although this clip only allows you to count for 30 seconds, remember, it is best to count the apical pulse for one minute.)

Audio clip 3.3: Apical pulse

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Respirations

Count the respirations, then click on the hand icon on the video to submit your answer. Please note: there is no sound in this video.

Technique

Put the steps in the correct order for each of the pulse and respiration techniques.

Measurement of pulse and respiration is important because these vital signs provide current data about the client’s health and illness state. Changes in pulse and respiration act as cues for healthcare providers’ diagnostic reasoning.

Pulse can be measured in many locations. When determining the best location, healthcare providers consider the client’s age and health and illness state, as well as the reason for taking the pulse.

When determining the relevance of pulse and respiration data, healthcare providers consider the client’s baseline data and the situation. Diagnostic reasoning about pulse and respiration always considers additional information, including other vital sign measurements and subjective and objective client data.

What is Oxygen Saturation?

Oxygen saturation refers to the percentage of hemoglobin molecules saturated with oxygen. Hemoglobin molecules can each carry four oxygen molecules; the oxygen binds or attaches to hemoglobin molecules. Oxygen saturation provides information about how much hemoglobin is carrying oxygen, compared to how much hemoglobin is not carrying oxygen.

Why is Oxygen Saturation Measured?

Healthcare providers measure oxygen saturation because it provides information about a client’s state of health. The body’s tissues and organs require oxygen for metabolism, and oxygen saturation can reveal whether there is sufficient oxygen in the blood or whether the client is in a state called hypoxemia (insufficient oxygen in the blood).

Oxygen saturation levels can influence clinical decisions about whether the client is receiving sufficient oxygen and/or requires supplemental oxygen. Oxygen saturation levels are also monitored during and after surgeries and treatments and to assess a client’s capacity for increased activity.

Oxygen saturation can be measured using a pulse oximetry device, which is a non-invasive method to measure arterial oxygen saturation level. See Figure 4.1 for a pulse oximeter. In critically ill clients, a more invasive and continuous monitoring system is used to measure arterial blood gases through an arterial line. An arterial line is a catheter that is inserted into an artery, usually the radial artery. It provides a way to access blood gases including arterial oxygen saturation (SaO2). Here, we focus on pulse oximetry because it is identified as a vital sign.

Figure 4.1: A pulse oximeter

A pulse oximetry device includes a sensor that measures light absorption of hemoglobin and represents arterial SpO2 (OER #1). Oxyhemoglobin and unoxygenated hemoglobin absorb light differently. The sensor measures “the relative amount of light absorbed by oxyhemoglobin and unoxygenated (reduced) hemoglobin” and compares the amount of “light emitted to light absorbed” (Jarvis, 2014, p. 164). This comparison is then converted to a ratio and is expressed as a percentage of Sp02.

The sensor is attached using various devices. One is a spring-loaded clip attached to a finger or toe as shown in Figure 4.1. It is used when an intermittent measurement is required. However, this clip is too large for newborns and young children, so for this population, the sensor is taped to a finger or toe. See Figure 4.2. This technique is also used for clients who require continuous monitoring.

Figure 4.2: Pulse oximeter with sensor taped around finger.

An earlobe clip is another useful device for clients who cannot tolerate the finger or toe clip or have a condition that could affect the results, such as vasoconstriction and poor peripheral perfusion. Another type of device is taped across the forehead and left in place for continuous monitoring. See Figure 4.3.

Figure 4.3: Pulse oximeter with device across forehead.

Chapter Attributions

Part of this content was adapted from OER #1 (as noted in brackets above):

• © 2015 British Columbia Institute of Technology (BCIT). Clinical Procedures for Safer Patient Care by Glynda Rees Doyle and Jodie Anita McCutcheon, British Columbia Institute of Technology. Licensed under a Creative Commons Attribution 4.0 International License, except where otherwise noted. Download this book for free at http://open.bccampus.ca

The acceptable oxygen saturation range is 97–100% (OER #1).

Older adults typically have lower oxygen saturation levels than younger adults. For example, someone older than 70 years of age may have an oxygen saturation level of about 95%, which is an acceptable level.

It is important to note that the oxygen saturation level varies considerably based on a person’s state of health. Thus, it is important to understand both baseline readings and underlying physiology associated with certain conditions to interpret oxygen saturation levels and changes in these levels.

• People who are obese and/or have conditions such as lung and cardiovascular diseases, emphysema, chronic obstructive pulmonary disease, congenital heart disease and sleep apnea tend to have lower oxygen saturation levels.
• Smoking can influence the accuracy of pulse oximetry in which the the SpO2 is low or falsely high depending on whether hypercapnia is present. With hypercapnia, it is difficult for the pulse oximeter to differentiate oxygen in the blood from carbon monoxide (caused by smoking).
• Oxygen saturation levels may decrease slightly when a person is talking.
• Oxygen saturation may remain normal (e.g., 97% and higher) for people with anemia. However, this may not indicate adequate oxygenation because there are less hemoglobin to carry an adequate supply of oxygen for people who have anemia. The inadequate supply of oxygen may be more prominent during activity for people with anemia.
• Falsely low oxygen saturation levels may be associated with hypothermia, decreased peripheral perfusion, and cold extremities. In these cases, an ear lobe pulse oximeter device or arterial blood gases would provide a more accurate oxygen saturation level. However, arterial blood gases are usually only taken in critical care or emergency settings.

Please answer the four questions in the following question set.

Chapter Attributions

Part of this content was adapted from OER #1 (as noted in brackets above):

• © 2015 British Columbia Institute of Technology (BCIT). Clinical Procedures for Safer Patient Care by Glynda Rees Doyle and Jodie Anita McCutcheon, British Columbia Institute of Technology. Licensed under a Creative Commons Attribution 4.0 International License, except where otherwise noted. Download this book for free at http://open.bccampus.ca

Technique

The pulse oximeter probe is clipped onto or taped around a client’s finger, as shown in Figure 4.4. The device displays an oxygen saturation level and a pulse within a few seconds. Palpate the client’s radial pulse (taken for 30 seconds if regular and one minute if irregular) while the oximeter is attached to the finger. The healthcare provider can have confidence in the accuracy of the measurement of the oxygen saturation level if the pulse displayed on the oximeter coincides with the radial pulse.

Figure 4.4: Measuring oxygen saturation.

While watching the following interactive video, apply your knowledge and critical thinking skills to answers the questions throughout the video. This video is repeated, uninterrupted, at the end of the chapter to facilitate seamless practice.

What should the healthcare provider consider?

Many factors can influence accuracy when measuring oxygen saturation levels via pulse oximetry. Certain conditions, including poor circulation and peripheral vasoconstriction, can lead to inaccurate oxygen saturation measurements when the device is attached to a finger or toe. Vasoconstriction involves narrowing of the vessels, so blood flow is reduced to the peripheries. This can reduce the accuracy of the reading and reduce the oximeter’s capacity to detect a signal. Readings may also be inaccurate (low) if a client’s hands or feet are cold or they have poor circulation. In cases like these, use an alternate method of measurement, like clipping a device to the earlobe or taping it to the forehead.

The healthcare provider cannot have confidence in measurement accuracy when the radial pulse does not coincide with the pulse displayed on the oximeter. It is also important to note that the pulse oximeter device cannot provide an accurate reading when oxygen saturation is below 75% (Shah & Shelley, 2013). Oxygen saturation levels in the 70s indicate that a client is decompensating and immediate intervention is required. Thus, it is important to confirm accuracy via additional assessments, such as assessing for respiratory distress, drawing arterial blood gases and/or checking for machine error.

The significance of the oxygen saturation level is interpreted in the context of the client’s baseline measurements, other data including vital signs and other objective and subjective findings, and the client’s overall health and wellness state.

Test Your Knowledge

Please answer the three questions in the following question set.

Now you have an opportunity to find errors in measurement techniques. The first activity involves watching a short film clip.

What error in technique is this healthcare provider making while measuring oxygen saturation in Film clip 4.1?

Film clip 4.1 Oxygen saturation taken incorrectly

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Now you have an opportunity to find errors in measurement techniques by looking at an image.

Which image shows the correct technique while measuring oxygen saturation?

Next, you have an opportunity to watch a short film clip on accurate measurement techniques. Watch this film clip 4.2 to see how to measure oxygen saturation correctly using a pulse oximeter. After the clip, try the technique yourself. You can watch the clip and practice as many times as you like.

Film clip 4.2: Oxygen saturation taken correctly

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Now that you have completed this chapter, it’s time to test your knowledge. Try to answer the following questions.  

Measuring oxygen saturation via pulse oximetry is a non-invasive way to quickly assess a client’s oxygen level. The results reflect a person’s oxygenation status and provide data for healthcare providers’ diagnostic reasoning.

The sensor can be attached in many ways, including clipping and taping probes to the finger, toe, earlobe, and forehead. The type and location of the apparatus is selected based on the client’s age, the presence of vasoconstriction, the adequacy of peripheral perfusion, whether intermittent or continuous monitoring is required, and the client’s health and illness state.

When determining the relevance of the oxygen saturation reading, healthcare providers consider the client’s health and wellness state. Specifically, they consider other data related to oxygenation including respiratory quality, rate, and rhythm; pulse; skin colour and temperature; and the client’s subjective description of ease or difficulty breathing. Decreases in oxygen saturation readings are potentially life-threatening and require immediate intervention.

Blood pressure is the force of blood exerted against the arterial walls, and is reported in millimetres of mercury (mm Hg). Try turning your kitchen tap on just a little bit, and then full blast. Compare the varying forces of water pressure as you adjust the tap. This comparison will give you a better sense of blood pressure.

The pressure against the arterial walls (the blood pressure) changes depending on whether the heart is contracting and pushing blood out into the arteries or whether the heart is in a resting phase and filling with blood. There is always force against the arterial walls, even when the heart is in a resting phase. The systolic pressure is the maximum pressure on the arteries during left ventricular contraction (systole) (OER #1). The left ventricle is a lower chamber of the heart responsible for pumping blood out to the body. The diastolic pressure is the resting pressure on the arteries between each cardiac contraction (OER #1) when the heart’s chambers are filling with blood (diastole).

Stroke volume is the amount of blood ejected from the left ventricle in a single contraction. Stroke volume provides information about the functioning of the heart. Stroke volume is influenced by age and typically ranges from 5–80 mL. Newborns have a stroke volume of about 5 mL per contraction while adults have a stroke volume of about 30–70 mL per contraction; the stroke volume increases as individuals grow and their hearts become stronger and can pump more volume per contraction. Direct measurement of stroke volume involves an invasive approach in which a catheter is passed into the pulmonary artery via a large neck vein; this monitoring device is only used during critical care situations.

Indirect measurement of stroke volume involves assessing the pulse pressure, which is the difference between the systolic and diastolic values and signifies the force required by the heart each time it contracts. For example, if someone’s blood pressure is 120/80 mm Hg, the pulse pressure is 40 mm Hg. A higher pulse pressure can indicate arterial stiffness, which often happens as a result of aging or cardiovascular disease. A higher pulse pressure can also be indicative of aortic valvular insufficiency where the diastolic pressure is unusually low and the systolic pressure is mildly elevated or unchanged. A lower pulse pressure can be a marker of poor heart function, where cardiac output is decreased.

Test Your Knowledge

Please answer the four questions in the following question set.

Chapter Attributions

Part of this content was adapted from OER #1 (as noted in brackets above):

• © 2015 British Columbia Institute of Technology (BCIT). Clinical Procedures for Safer Patient Care by Glynda Rees Doyle and Jodie Anita McCutcheon, British Columbia Institute of Technology. Licensed under a Creative Commons Attribution 4.0 International License, except where otherwise noted. Download this book for free at http://open.bccampus.ca

• A person’s blood pressure provides insight into the functioning of the body
• Healthy body functioning is influenced by healthy blood pressure
• The findings can provide information about the integrity of arteries and heart functioning, which can lead the healthcare provider to conduct additional assessments
• High blood pressure can cause the arteries to become weak and damaged and cause the heart to become weak and enlarged
• Low blood pressure can decrease perfusion of nutrients and oxygen to the body’s cells, influencing ability to function and potentially cellular death
• Chronic high blood pressure can contribute to conditions such as vascular disease, myocardial infarction, cerebral stroke, kidney disease, and dementia

Five factors influence blood pressure:

1. Cardiac output
2. Peripheral vascular resistance
3. Volume of circulating blood
4. Viscosity of blood
5. Elasticity of vessels walls

Blood pressure increases with increased cardiac output, peripheral vascular resistance, volume of blood, viscosity of blood and rigidity of vessel walls.

Blood pressure decreases with decreased cardiac output, peripheral vascular resistance, volume of blood, viscosity of blood and elasticity of vessel walls.

Cardiac Output

Cardiac output is the volume of blood flow from the heart through the ventricles, and is usually measured in litres per minute (L/min). Cardiac output can be calculated by the stroke volume multiplied by the heart rate. Any factor that causes cardiac output to increase, by elevating heart rate or stroke volume or both, will elevate blood pressure and promote blood flow. These factors include sympathetic stimulation, the catecholamines epinephrine and norepinephrine, thyroid hormones, and increased calcium ion levels. Conversely, any factor that decreases cardiac output, by decreasing heart rate or stroke volume or both, will decrease arterial pressure and blood flow. These factors include parasympathetic stimulation, elevated or decreased potassium ion levels, decreased calcium levels, anoxia, and acidosis.

Peripheral Vascular Resistance

Peripheral vascular resistance refers to compliance, which is the ability of any compartment to expand to accommodate increased content. A metal pipe, for example, is not compliant, whereas a balloon is. The greater the compliance of an artery, the more effectively it is able to expand to accommodate surges in blood flow without increased resistance or blood pressure. Veins are more compliant than arteries and can expand to hold more blood. When vascular disease causes stiffening of arteries (e.g., atherosclerosis or arteriosclerosis), compliance is reduced and resistance to blood flow is increased. The result is more turbulence, higher pressure within the vessel, and reduced blood flow. This increases the work of the heart.

Volume of Circulating Blood

Volume of circulating blood is the amount of blood moving through the body. Increased venous return stretches the walls of the atria where specialized baroreceptors are located. Baroreceptors are pressure-sensing receptors. As the atrial baroreceptors increase their rate of firing and as they stretch due to the increased blood pressure, the cardiac centre responds by increasing sympathetic stimulation and inhibiting parasympathetic stimulation to increase HR. The opposite is also true.

Viscosity of Blood

Viscosity of blood is a measure of the blood’s thickness and is influenced by the presence of plasma proteins and formed elements in the blood. Blood is viscous and somewhat sticky to the touch. It has a viscosity approximately five times greater than water. Viscosity is a measure of a fluid’s thickness or resistance to flow, and is influenced by the presence of the plasma proteins and formed elements within the blood. The viscosity of blood has a dramatic effect on blood pressure and flow. Consider the difference in flow between water and honey. The more viscous honey would demonstrate a greater resistance to flow than the less viscous water. The same principle applies to blood.

Elasticity of Vessel Walls

Elasticity of vessel walls refers to the capacity to resume its normal shape after stretching and compressing. Vessels larger than 10 mm in diameter are typically elastic. Their abundant elastic fibres allow them to expand as blood pumped from the ventricles passes through them, and then to recoil after the surge has passed. If artery walls were rigid and unable to expand and recoil, their resistance to blood flow would greatly increase and blood pressure would rise to even higher levels, which would in turn require the heart to pump harder to increase the volume of blood expelled by each pump (the stroke volume) and maintain adequate pressure and flow. Artery walls would have to become even thicker in response to this increased pressure.

Test Your Knowledge

Please answer the two questions in the following question set.

Chapter Attributions

All content on this page was adapted from OER #2:

• © Apr 10, 2017 OpenStax Anatomy and Physiology. Textbook content produced by OpenStax Anatomy and Physiology is licensed under a Creative Commons Attribution License 4.0 license. Download for free at http://cnx.org/contents/7c42370b-c3ad-48ac-9620-d15367b882c6@12

Blood pressure is reported in mm Hg (pronounced millimetres of mercury), in which the systolic is the numerator and diastolic is the denominator. See Table 5.1 for an overview of estimated blood pressure ranges for healthy individuals.

Factors that influence blood pressure include age, sex, ethnicity, weight, exercise, emotions/stress, pregnancy, and diurnal rhythm as well as medication use and disease processes.

• The general pattern is that blood pressure rises with age, so normal variations tend to be higher for older adults.
• Blood pressure is similar in childhood for males and females. After puberty, females have lower blood pressure than males, whereas after menopause females have higher blood pressure than males.
• Research has revealed that ethnicity may be a predictor of blood pressure, but this causation is not necessarily biological, but rather sociocultural. When determining risk for high blood pressure, it is important to consider ethnicity as a contributing factor.
• The diurnal cycle influences blood pressure to be lower in the morning and increase throughout the day until early evening. Try it out: take your blood pressure when you wake up in the morning and then again in late afternoon, and note the difference. This is one reason why healthcare providers document the time a client’s blood pressure is taken.
• Blood pressure can be higher in people who are obese because the heart has to work harder to perfuse the body’s tissues.
• The sympathetic nervous system is stimulated by exercise, stress, anxiety, pain, anger, and fear, which increases blood pressure. Blood pressure returns to baseline within five minutes of rest following activity. Try it out. Have a peer take your blood pressure. Then, run on the spot or do some other cardiac activity for five minutes. Have the peer take your blood pressure again, and then lie down and rest for five minutes. Take the blood pressure again. Note the changes.
• Blood pressure varies throughout the duration of pregnancy. It decreases about halfway through the first trimester until mid-pregnancy due to progesterone effects that relax the walls of blood vessels, causing decreased peripheral vascular resistance. It returns to pre-pregnancy values toward the end of pregnancy.

Test Your Knowledge

Please answer the seven questions on the following cards.

Blood pressure is measured in many ways including manual/auscultatory, automatic/electronic, cellular phone applications, and arterial catheters. Whatever method is used, blood pressure must be measured using validated equipment. It has been found that blood pressure is often not measured accurately in clinical practice, particularly when using the auscultatory/manual method. It is important to ensure correct technique to obtain an accurate measurement. Hypertension Canada (2020) recommends electronic blood pressure measurement as the preferred method in clinical practice.

Client Positioning

Blood pressure is generally taken in a sitting or supine position with the bare arm at heart level (OER #1). Certain health states prevent some clients from sitting, such as clients who are critically ill, unstable, or postoperative. Thus, healthcare providers document the client’s positioning (e.g., sitting, supine, standing). If sitting, the feet are placed flat on the floor with the back resting comfortably against a chair. The healthcare provider checks to ensure that the client’s legs are not crossed, because this can increase blood pressure. The client sits resting for five minutes before you take the blood pressure. This waiting period is not feasible when the client’s condition is deteriorating or a STAT blood pressure is required. Because the client should be resting, you should ask them not to talk or move. Additionally, you should not ask them to hold any of your equipment during the blood pressure measurement.

Cuff Types and Sizes

Manual and automatic blood pressure measurement involves using a blood pressure cuff with a sphygmomanometer. Many cuff sizes are available to fit newborns, children, adults, people with small and larger arms, and people with cone-shaped arms. The cuff is typically wrapped around the upper arm. However, there is also a cuff that can be placed on the thigh when the arm is not feasible. See Figure 5.1 of varying blood pressure cuff sizes. Wrist devices can be used for blood pressure estimation when clients have a large upper arm circumference (Nerenberg, 2018). When taking the measurement, make sure that the arm and wrist are supported at heart level (Nerenberg, 2018).

Figure 5.1: Varying blood pressure cuff sizes.

It is important to choose a cuff size that matches the client’s arm size, rather than their age. See Table 5.2 about cuff sizing. See Film Clip 5.1 of a demonstration of accurate cuff sizing.

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Film clip 5.1: Accurate cuff sizing

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Before placing the blood pressure cuff on the client’s arm, palpate the brachial artery using three fingers (not your thumb) just above the antecubital fossa medially (OER #1). To do this, palpate the bicep tendon at the antecubital fossa. Move 2 cm medially from the tendon and 2–3 cm above the antecubital fossa. Press firmly to feel the brachial pulse.  Wrap the blood pressure cuff securely and evenly around the client’s upper, bare arm (not over clothing) with the cuff’s artery marker aligned with the brachial artery and about 3cm above the antecubital fossa.

Blood Pressure Methods

Manual blood pressure measurement is taken using a blood pressure cuff with a sphygmomanometer and a stethoscope. See Figure 5.2. This technique is detailed on next page.

Figure 5.2: Blood pressure cuff with a sphygmomanometer and a stethoscope.

Automatic blood pressure cuffs are a digital way to measure blood pressure. See Figure 5.3. After positioning the client and the blood pressure cuff on the arm, press the start button on the monitor. The cuff is automatically inflated and then deflates at a rate of 2 mm Hg per second. The monitor has a digital display that shows the blood pressure reading when done. Automatic cuffs can be programmed to take a series of blood pressure readings in a row. If the healthcare provider is concerned about an initial high blood pressure reading on a client, the accuracy of the blood pressure is verified with the following actions:

• have the client sit in a room by themselves
• quiet the room
• dim the lights
• allow the client to sit quietly, without talking
• then take three measurements, a few minutes apart, with the automatic cuff. The blood pressure displayed is an average of the three readings.

Figure 5.3: Automatic blood pressure cuff.

Clients can monitor their own blood pressure at home with an automatic digital blood pressure monitoring device. Clients are advised to use a device that meets the standards of the Association for the Advancement of Medical Instrumentation, the requirements of the British Hypertension Society protocol, or the International Protocol for Validation of Automated Blood Pressure Measuring Devices. The cuff is applied around the client’s upper arm or wrist. Similar to the automatic cuff noted above, the client presses the start button and the cuff inflates and deflates based on programmed levels displaying a digital reading. Clients are encouraged to document their blood pressure or use a device with data-recording capabilities to increase the reliability of their reported home blood pressure monitoring. These data can be shared with the client’s primary care provider.

Arterial catheters are an invasive way to measure blood pressure and are only used in critical care situations when continuous blood pressure monitoring and arterial blood gas draws are required. This involves insertion of a catheter (similar to an intravenous) into the artery. The catheter is connected to a pressure transducer and monitor that provide a digital blood pressure reading.

Cellular phone applications have been developed to measure blood pressure, but the accuracy of this technology is still being investigated.

Chapter Attributions

Part of this content was adapted from OER #1 (as noted in brackets above):

• © 2015 British Columbia Institute of Technology (BCIT). Clinical Procedures for Safer Patient Care by Glynda Rees Doyle and Jodie Anita McCutcheon, British Columbia Institute of Technology. Licensed under a Creative Commons Attribution 4.0 International License, except where otherwise noted. Download this book for free at http://open.bccampus.ca

A healthcare provider uses a stethoscope and a blood pressure cuff with a sphygmomanometer to measure blood pressure manually. The stethoscope is used to listen to the blood pressure sounds, which are called Korotkoff sounds.

Stethoscope Usage and Korotkoff Sounds

The stethoscope is used on bare skin so that a client’s clothing does not affect the sounds. The stethoscope does not make sounds louder; it simply blocks out extraneous noises so you can better hear the Korotkoff sounds. These sounds are heard through a stethoscope applied over the brachial artery when the blood pressure cuff is deflating. You will not hear anything when you first place the stethoscope over the brachial artery because unobstructed blood flow is silent. The Korotkoff sounds appear after you inflate the cuff (which compresses the artery/blood flow) and then begin to deflate the cuff. The Korotkoff sounds are the result of the turbulent blood caused by the inflated cuff compressing the artery and oscillations of the arterial wall when the heart beats during cuff deflation.

Here are a few tips:

• Use a high quality stethoscope with durable, thick tubing. Avoid stethoscopes with long tubing because this can distort sounds.
• Ensure quiet surroundings so that you can better hear the Korotkoff sounds.
• Make sure that the slope of the stethoscope earpieces point forward or toward your nose.
• Use a stethoscope that has both bell and diaphragm capacity. See Figure 5.4 for bell and diaphragm.

Figure 5.4: Stethoscope with bell and diaphragm. (Illustration credit:  Hilary Tang)

• Cleanse the stethoscope prior to use including the ear pieces and the bell and diaphragm.
• The bell of the stethoscope is suggested because it is used for low-pitched sounds like blood pressure. However, some healthcare providers use the diaphragm for several reasons: that is how they learned to take blood pressure; they believe this helps them hear the Korotkoff sounds better; and the diaphragm covers a larger surface area than the bell.
• Hold the bell lightly against the skin with a complete seal or hold the diaphragm firmly against the skin with a complete seal.
• You must ensure that the bell or diaphragm is open before using. See Film Clip 5.2 on how to open and close the bell and diaphragm.

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Film clip 5.2: Opening and closing the bell and diaphragm

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Determining Maximum Inflation Pressure

Healthcare providers determine the maximum inflation pressure before they take blood pressure. The maximum inflation pressure is the number on the sphygmomanometer that the cuff is inflated to when measuring blood pressure. If you do not determine the maximum pressure inflation, an auscultatory gap could go unrecognized, and as a result the blood pressure could be underestimated (lower than the actual value).

An auscultatory gap is a silent interval when the Korotkoff sounds go absent and then reappear while you are deflating the cuff during blood pressure measurement. This gap is an abnormal finding and can occur due to arterial stiffness and arteriosclerotic disease. It is typically observed in people with a history of hypertension who have been treated with prolonged antihypertensive medication.

To determine the maximum inflation pressure, start by palpating the brachial or radial pulse while inflating the cuff. Inflate the cuff 30 mm Hg quickly past the point when you obliterate the pulse (ie., you no longer feel the pulse). If you still cannot feel the pulse, use that value to start auscultating – that value is the maximum inflation pressure number.

When taking blood pressure, if an auscultatory gap is observed, document the first systolic sound and diastolic sound only. Report the presence of an auscultatory gap in narrative notes.

Blood Pressure Measurement Techniques

For novices, it is a good idea to start with the two-step technique and then move onto the one-step technique as you develop your skills.

Two-step technique

First step: Determining maximum pressure inflation

Palpate the radial or brachial artery, inflate the blood pressure cuff until the pulse is obliterated, and then continue to inflate 30 mm Hg more (OER #1). Note this number – it is considered the maximum pressure inflation. Next, deflate the cuff quickly.

Second step: Measure blood pressure

Now, you can start to measure blood pressure. Place the bell of the cleansed stethoscope over the brachial artery (OER #1) using a light touch and complete seal. Inflate the cuff to the maximum pressure inflation number (OER #1). Open the valve slightly. Deflate the cuff slowly and evenly (OER #1) at about 2 mm Hg per second. See Film Clip 5.3 which focuses on the speed of the needle when deflating the blood pressure cuff.

Note the points at which you hear the first appearance of Korotkoff sounds (systolic blood pressure) (OER #1) and the point at which the Korotkoff sounds go silent (diastolic blood pressure) (Hypertension Canada, 2020). These sounds are called Korotkoff sounds and vary in quality from tapping, swooshing, muffled sounds, and silence. The pressure at which the first Korotkoff sound is noted signifies the systolic pressure, while the pressure at which the Korotkoff sounds are no longer heard marks the diastolic pressure.

See Audio Clip 5.1 to listen to Korotkoff sounds and noting systolic and diastolic blood pressure. Alternatively, if viewing textbook as a PDF, use this link: https://www.youtube.com/embed/lPlYNt8cVnI?rel=0

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Film clip 5.3: Deflation rate of sphygmomanometer

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Test Yourself!

While watching the interactive video on blood pressure measurement using the two-step technique, apply your knowledge and critical thinking skills to answer the questions throughout the video. Please note: there is no sound in this video.

One-step technique: Determining maximum pressure inflation and taking blood pressure

Palpate the radial or brachial artery, inflate the blood pressure cuff until the pulse is obliterated (OER #1), and then quickly continue to inflate 30 mm Hg more (Hypertension Canada, 2020). Place the bell of the cleansed stethoscope over the brachial artery (OER #1) using a light touch with a complete seal. Open the valve slightly. Deflate the cuff slowly and evenly (OER #1) at about 2 mm Hg per second. Note the points at which you hear the first Korotkoff sound (systolic blood pressure) (OER #1) and the point in which the Korotkoff sounds go silent (diastolic blood pressure) (Hypertension Canada, 2020). These sounds are called Korotkoff sounds and vary in quality from tapping, swooshing, muffled sounds, and silence. The first Korotkoff sound is the systolic pressure, and the diastolic pressure is when the Korokoff sounds go silent.

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Audio clip 5.1: Korotkoff sounds with blood pressure

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Test Yourself!

While watching the interactive video on blood pressure measurement using the one-step technique, apply your knowledge and critical thinking skills to answer the questions throughout the video. Please note: there is no sound in this video.

Test Your Knowledge

Chapter Attributions

Part of this content was adapted from OER #1 (as noted in brackets above):

• © 2015 British Columbia Institute of Technology (BCIT). Clinical Procedures for Safer Patient Care by Glynda Rees Doyle and Jodie Anita McCutcheon, British Columbia Institute of Technology. Licensed under a Creative Commons Attribution 4.0 International License, except where otherwise noted. Download this book for free at http://open.bccampus.ca

Manual blood pressure is reported in even numbers. Healthcare providers always measure blood pressure with pulse because these vital signs are closely related and data from both are needed to make accurate and informed clinical decisions.

What Should You Do if You Cannot Feel the Brachial Pulse?

• To locate the brachial pulse, palpate the bicep tendon, move medially about 2 cm, and move up about 2–3 cm
• Use three fingers including your index and middle finger to feel for the pulse
• You will usually need to press fairly firmly to palpate the brachial pulse and may need to modify the pressure. If you press too hard, you will obliterate the pulse (make it disappear) and if you press too lightly, you will not be able to feel the pulse
• You may need to reposition your fingers to find the best place to feel the pulse along the brachial artery
• Place the client’s arm with the palm up and elbow extended. You can flex the elbow in varying degrees to relax the muscle and accentuate the pulse
• Cup your opposite hand under the client’s elbow

What Should You Do if You Cannot Hear the Korotkoff Sounds?

• Use your bell and make full contact with skin
• Make sure the bell is positioned over the brachial artery
• Ensure the room is quiet
• Concentrate on expected sounds (swooshing, tapping, muffled sounds)
• Try different earbuds (hard or soft) on your stethoscope

Common Errors When Taking Blood Pressure

Many errors must be avoided when measuring blood pressure.

• Failure to determine maximum pressure inflation can produce a falsely low systolic reading.
• Deflating the cuff too slowly can produce a falsely high diastolic, and deflating the cuff too quickly can produce a falsely low systolic or falsely high diastolic reading.
• Inaccurate cuff sizes for the client’s arm size and shape can result in measurement error: a cuff that is too narrow can produce a falsely high blood pressure whereas a cuff that is too loose can produce a falsely low blood pressure.
• A falsely low blood pressure can result from the arm being positioned above the level of the heart and a falsely high blood pressure can result from the arm being positioned below the level of the heart.

A number of factors can cause hypotension (low blood pressure). Hypotension is considered less than 95/60 mm Hg in a normotensive adult. However, low blood pressure measurements are always interpreted in the context of a client’s baseline and past blood pressure readings as well as their current health state. Common symptoms associated with hypotension are lightheadedness, loss of consciousness, blurry vision, clammy skin, and fatigue.

Orthostatic Hypotension

Orthostatic hypotension is a drop in blood pressure when the client moves from lying to sitting to a standing position.

Have you ever stood up quickly and felt dizzy for a moment? This is because, for one reason or another, blood is not getting to your brain so it is briefly deprived of oxygen. When you change position from sitting or lying down to standing, your cardiovascular system has to adjust for a new challenge, keeping blood pumping up into the head while gravity is pulling more and more blood down into the legs. The reason for this is a sympathetic reflex that maintains the output of the heart in response to postural change. This sympathetic reflex keeps the brain well oxygenated so that cognitive and other neural processes are not interrupted. Sometimes this does not work properly. If the sympathetic system cannot increase cardiac output, then blood pressure into the brain will decrease, and a brief neurological loss can be felt. This can be brief, such as a slight ‘wooziness’ when standing up too quickly, or could lead to a loss of balance and neurological impairment for a period of time. The name for this is orthostatic hypotension, which means that blood pressure falls below the homeostatic set point when standing. It can be the result of standing up faster than the reflex can occur, which may cause a benign ‘head rush,’ or it may be the result of an underlying cause.

There are two basic reasons why orthostatic hypotension occurs. First, blood volume is too low and the sympathetic reflex is not effective. This hypovolemia may be the result of dehydration or medications that affect fluid balance, such as diuretics or vasodilators. The second underlying cause of orthostatic hypotension is autonomic failure. Several disorders can result in compromised sympathetic functions, ranging from diabetes to multiple system atrophy (a loss of control over many systems in the body), and addressing the underlying condition can improve the hypotension. Orthostatic hypotension is more common with advancing age and can be aggravated by antihypertensive medications.

How to Assess Orthostatic Hypotension

Orthostatic hypotension is assessed by measuring orthostatic or postural blood pressure and pulse changes. This procedure is done by assessing when the client moves from supine to sitting to standing. There are variations in how this procedure is done in terms of timing. Here is a common way to proceed:

1. The client rests supine for three minutes.
2. Take blood pressure and pulse in supine position.
3. The client sits up with feet dangling.
4. Take blood pressure and pulse within two minutes of position change.
5. The client stands up.
6. Take blood pressure and pulse within two minutes of position change.

How to Evaluate the Findings 

Normal variation is a 10 mm Hg decrease in blood pressure from lying to standing and an increase in pulse of 10–15 bpm.

A decrease in blood pressure from lying to standing of systolic ≥ 20 mm Hg or diastolic ≥ 10 mm Hg is identified as orthostatic hypotension.

An increase in pulse from lying to standing of ≥ 20 bpm is identified as orthostatic pulse.

Test Your Knowledge

Please answer the five questions in the following question set.

Chapter Attributions

The content under the sub-title “Orthostatic Hypotension” was adapted from OER #2 (as noted in brackets above):

• © Apr 10, 2017 OpenStax Anatomy and Physiology. Textbook content produced by OpenStax Anatomy and Physiology is licensed under a Creative Commons Attribution License 4.0 license. Download for free at http://cnx.org/contents/7c42370b-c3ad-48ac-9620-d15367b882c6@12

Chronically elevated blood pressure is known clinically as hypertension. It is defined as chronic and persistent blood pressure measurements of 140/90 mm Hg or above (OER #2) in the adult. However, the specific measurement in which hypertension is diagnosed depends on many factors. As per Hypertension Canada (Nerenberg, et al., 2018), some of these factors include whether it is the first or second visit to have blood pressure assessed and whether the blood pressure is assessed using automatic or manual measurement devices. It is always important to look at the most current guidelines related to hypertension. See Table 5.3 for the guidelines related to management, including monitoring and treatment, recommended by Hypertension Canada (Nerenberg, et al., 2018).

Hypertension is typically a silent disorder, so hypertensive clients may not recognize the seriousness of their condition and not adhere to their treatment plan. The result is often a heart attack or stroke. Hypertension may also lead to an aneurysm (ballooning of a blood vessel caused by a weakening of the wall), peripheral arterial disease (obstruction of vessels in peripheral regions of the body), chronic kidney disease, or heart failure. (OER#2)

Common errors in measurement and natural fluctuations in blood pressure can result in readings that erroneously suggest hypertension. Some of the errors are due to the operator (i.e., the healthcare provider) and others are due to client anxiety and situational determinants. As a healthcare provider, it is important to review your technique to assess possible measurement errors and assess the client for factors that could elevate blood pressure. If the client’s blood pressure is elevated, repeat the measurement for accuracy and take the blood pressure in the opposite arm.

Because hypertension is a silent disorder, healthcare providers measure blood pressure at regular intervals. The intervals depend on the client’s health status and risk factors. Before a diagnosis of hypertension is made, blood pressure is monitored over days, weeks, or months either in the office using an automatic blood pressure machine, or at home using an ambulatory blood pressure machine.

Clients demonstrating features of a hypertensive urgency or emergency (e.g., hypertensive encephalopathy, acute coronary syndrome, acute ischemic stroke, intracranial hemorrhage) are diagnosed as hypertensive and treated immediately.

Guidelines to Determine Hypertension

Hypertension Canada (Leung, et al., for Hypertension Canada, 2017) states that when assessing chronic high blood pressure, readings must be done under the following conditions:

• No acute anxiety, stress, or pain
• No caffeine, smoking, or nicotine in the preceding 30 minutes
• No use of substances containing adrenergic stimulants such as phenylephrine or pseudoephedrine (may be present in nasal decongestants or ophthalmic drops)
• Bladder and bowel comfortable
• No tight clothing on arm or forearm
• Quiet room with comfortable temperature
• Rest for at least five minutes before measurement
• Ask the client to stay silent prior and during the procedure

See Table 5.3 for the guidelines related to management, including monitoring and treatment, in the adult, recommended by Hypertension Canada (Nerenberg, et al., 2018). These recommendations are based on in-office visit one. At least two or more readings are taken during the same visit. If assessing blood pressure, the first reading is discarded and the latter two readings are averaged. You should wait one minute in between blood pressure measurements (Hypertension Canada, 2020). Additionally, multiple readings may be needed when the client has an arrhythmia (Hypertension Canada, 2020)

The healthcare provider assesses a client’s cardiovascular risk factors for atherosclerosis and hypertension. These risk factors are categorized as modifiable and non-modifiable. See Table 5.4 for an overview of risk factors adapted based on Hypertension Canada guidelines (Leung, et al., for Hypertension Canada, 2017)

Test Your Knowledge

Please answer the three questions in the following question set.

Chapter Attributions

Part of this content was adapted from OER #2 (as noted in brackets above):

• © Apr 10, 2017 OpenStax Anatomy and Physiology. Textbook content produced by OpenStax Anatomy and Physiology is licensed under a Creative Commons Attribution License 4.0 license. Download for free at http://cnx.org/contents/7c42370b-c3ad-48ac-9620-d15367b882c6@12

Now you have an opportunity to find the errors in measurement techniques. The first activity involves watching a short film clip. Check it out!

What errors in technique is this healthcare provider making while taking blood pressure?

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Film clip 5.4: Errors in blood pressure measurement

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Next, you have an opportunity to watch film clips on accurate measurement techniques. There are two activities that involve two film clips about blood pressure measurement techniques. Watch each of them and then try it out yourself.

Please note: The first film clip refers to the two-step blood pressure approach. This approach is used for learners. As you become more proficient, you can try the one-step blood pressure approach.

Two-step Blood Pressure

Watch this teaching video of a film clip that shows the two-step blood pressure approach. This approach is best used when you are first learning how to take blood pressure. Watch the clip and then try it out!

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Film clip 5.5: Two-step blood pressure approach

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One-step Blood Pressure

Watch this teaching video of a film clip that shows the one-step blood pressure approach. After you become proficient in the two-step approach, you can move on to the one-step blood pressure approach. Watch the clip and then try it out!

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Film clip 5.6: One-step blood pressure approach

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Now that you have completed this chapter, it’s time to test your knowledge. Try to answer the following questions (you may want to review parts of the chapter before answering).

1. Watch and listen to the Korotkoff sounds while blood pressure is taken in audio clip 5.2. What is the systolic and diastolic blood pressure?

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Audio clip 5.2: Korotkoff sounds

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2. Watch and listen to the Korotkoff sounds while blood pressure is taken in audio clip 5.3. What is the systolic and diastolic blood pressure?

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Audio clip 5.3: Korotkoff sounds

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3. Which one of the two images below (Figure 5.5 or Figure 5.6) demonstrates the correct way of putting the ear pieces of the stethoscope in your ears?

Figure 5.5

Figure 5.6

Blood pressure measurement is important because it provides objective data about the client’s health and illness state. Changes in blood pressure act as a cue for healthcare providers’ diagnostic reasoning. Blood pressure fluctuates with internal and external factors. Therefore, it is important to take more than one measurement before making clinical decisions.

It is always important to ensure correct techniques when taking blood pressure.

In determining the relevance of the blood pressure reading, the healthcare provider considers the client’s baseline blood pressure, previous readings, and health status. The blood pressure reading is always taken in conjunction with a pulse. Diagnostic reasoning takes into account blood pressure, pulse, and subjective and objective client data.

In healthcare, knowledge integration involves drawing upon and synthesizing client data to inform diagnostic reasoning and clinical decision-making. Healthcare providers are continually evaluating whether vital sign measurements are normal or abnormal. The analysis takes into consideration the client’s baseline vital sign measurements as well as the client’s age and health and illness state. Additionally, healthcare providers pay attention to trending, which involves looking at vital signs across time to detect changes. If abnormalities are identified, healthcare providers consider the client context including other subjective and objective data to differentiate relevant from irrelevant data. The analysis of client data influences evidence-informed clinical decision-making in which healthcare providers identify priority actions and treatment options.

This chapter presents seven case studies based on what you learned in chapters 1–5. The case studies are intended to provide an opportunity for you to critically think about client data in the context of a client situation. You will integrate your knowledge about normal and abnormal vital signs and engage in diagnostic reasoning to determine priority actions and next steps based on the client data.

• Case Study: Pediatric Client
• Case Study: Adolescent Client
• Case Study: Pregnant Adult Client
• Case Study: Adult Client
• Case Study: Older Adult Client
• Case Study: Dental Office Visit
• Case Study: Temperature, Pulse & Respiration

Layout

Data about each case study are provided with a series of critical thinking questions. Be sure to answer all the questions before moving forward in the case study.

Initial Assessment Data

• Biographical data: 18-month-old child
• Reason for seeking care: Febrile
• History of presenting illness: Fever x 2 days, today rash appeared consisting of red spots over the client’s body
• Past history: No medications, no illnesses

Use the slider to uncover the correct way to document the following assessment data.

At 1700 hrs on June 20, 20xx

• Temperature: 39°C axilla
• Pulse: 170 bpm (apical) cyclical increases with inspiration, force 2+, regular rhythm
• RR 30 bpm, regular rhythm
• Spo2 saturation 98%

Initial Assessment Data

• Biographical data: Adolescent client (age 14)
• Reason for seeking care: Post-op surgery
• History of health/illness: Healthy
• Past history: No medications, no illnesses
• Client had abdominal surgery and was transferred from the recovery room to the surgical floor. Lethargic and oriented x 3. Awakens when name is called and responds to questions appropriately. Client rates pain 2/10. The healthcare provider assesses client’s vital signs every 30 minutes x 2 hours.

Vital Sign Record

Please note: The following documentation exercise has extended columns for interactivity. A vital signs documentation record would have narrow columns and rows as you have seen in previous case studies.

Now review the documentation for Mr. Turner’s blood pressure. Examine the following examples of documentation and choose the image that represents the correct way to document the findings. The results were:

• 1050 hrs: BP 160/94,  P 72 (right arm)
• 1058 hrs: BP 156/92,  P70 (right arm)
• 1100 hrs: BP 148/90,  P70 (left arm)
• 1105 hrs: BP 150/86,  P66 (right arm)
• 1107 hrs: BP 144/84,  P68 (right arm)
• 1109 hrs: BP 156/82,  P62 (right arm)

To move to the next part of the scenario, click on “Proceed” in the top right hand corner.

To move to the next part of the scenario, click on “Proceed” in the top right hand corner.

Watch the interactive video on measuring vital signs with an automated vital signs monitor below, noting important considerations as you follow along. Please note: there is no sound in this video.

As you become more proficient in measuring vital signs and interpreting the findings, you should remember a few key points.

There are many methods to take vitals signs. The correct technique is essential to obtaining an accurate measurement.

Vital sign measurements have very little meaning on their own. Healthcare providers engage in critical thinking and correlate these measurements with subjective and other objective data. Thinking critically about these measurements will best inform clinical decision-making. Healthcare providers look holistically at the person and their health and wellness state to determine whether vital sign measurements are within normal limits for this individual person.

It is also essential to acknowledge that clients may have additional information that can provide insight into their body, which may influence the technique and location for measuring vital signs and the significance of the findings. Sharing findings with clients is also a good opportunity for health promotion teaching.

Figure 7.1: Cells. (Illustration credit: Hilary Tang)

Artist Statement – Cells

The human body is a messy phenomenon. From the organ to the cell, the brain to the neurotransmitter, like clockwork, everything is constantly happening. Down to our very core, the tiniest components are working in conjunction, harmoniously, to let us eat, breathe, and move. Without our constant consciousness, we are living. What an organized chaos our bodies are.

Temperature

Pulse and Respiration

Oxygen Saturation

Blood Pressure

Beasley, R., Chien, J., Douglas, J., Eastlake, L., Farah, C., King, G., Moore, R., Pilcher, J., Richards, M., Smith, S., & Walters, H. (2016). Target oxygen saturation range: 92–96% versus 94–98%. Respirology, 22(1), 200–202

Fech, T., Penrod, J., Battistone, M., Sawitzke, A., & Stults, B. (2012). The prevalence and clinical correlates of an auscultatory gap in systemic sclerosis patients. International Journal of Rheumatology, doi: 10.1155/2012/590845

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Leduc, D., & Woods, S., (2017). Canadian Paediatric Society Position Statement: Temperature measurement in paediatrics. Retrieved from: http://www.cps.ca/en/documents/position/temperature-measurement

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