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Clinical Nursing Skills

15.1 Performing a General Survey

Clinical Nursing Skills15.1 Performing a General Survey

Learning Objectives

By the end of this section, you will be able to:

  • Differentiate between normal and abnormal findings in the general survey
  • Describe nursing observational and interviewing skills needed for performing a general survey assessment
  • Identify instruments needed for proper measurement

Nurses know that patients are more than just data. Data, such as vital signs and measurements, do provide a wealth of information, but the key to determining an individual’s health is combining that critical data with the nurse’s observation of the patient. The nurse’s observations also provide a source of important information. For an individual to be at peak health, a state of homeostasis must be achieved. Homeostasis is regulated without compensation from external sources or systems. Often body systems work in tandem to create a whole body homeostasis. Examples include blood sugar regulation after a meal or body temperature regulation.

Generalized Survey of Patient’s Health Status

The nurse walks into the patient’s room for the first time and can already begin assessing before even seeing the patient. What does the nurse feel, hear, and smell? Is the room temperature appropriate? Is the television volume up abnormally high? Are there any unusual smells? Then the nurse meets the patient and gains more information. What does the patient look like? Are they awake? Are they struggling to breathe? What can the nurse gather from the patient’s verbal and nonverbal communication? During the first meeting of the nurse and patient, assessment has already begun. First impressions matter, both in social settings and health care. Just as confidence and a smile leave a good first impression in social settings, a patient’s appearance, behavior, age, culture, size, and cognition should be noted and may be used to provide further information to determine the patient’s health needs.

Patient Appearance

The first thing a nurse notices in patients is appearance. Objective assessment questions can provide valuable information for the nurse at the beginning of the assessment. What is the patient’s age? What is their height and weight? Are there any noteworthy nonverbal cues, such as indications of pain, anger, or fear? What is their mobility status? Do they use assistive devices? The answers to these questions can guide the nurse’s assessment.

Other data gained during the first encounter can also guide the nurse’s assessment. Specifically, the nurse should note if the patient is well groomed, dressed appropriately for the weather, appears comfortable, is a healthy size, and the color and tone of the patient’s skin. The patient’s color and tone should be examined to note pallor, flushing, dryness, the presence of moisture, and areas of discoloration. These are just some of the observations that could help a nurse pinpoint an abnormality. A patient who is not well-groomed or well-dressed could be struggling to be able to perform activities of daily living independently. An inability to perform these activities may be due to physical or mental limitations. A patient who appears uncomfortable could be struggling with pain or difficulty breathing. An abnormal gait may also suggest an underlying physical limitation. A patient’s size and weight could be estimated not only to determine the type of scale needed but also to provide general information about the patient’s activity and muscle mass. A weight measurement gives an objective assessment of the patient’s size; however, it does not classify the overall health of an individual. Since a weight measurement alone does not give a complete assessment of health, weight measures are typically considered in context with height, other physical attributes such as muscle mass, and body processes such as pregnancy. Abnormalities noted during an assessment of the patient’s skin are also an indication that a more detailed assessment is needed. Abnormal skin coloring and tone may require further investigation. Paleness of the skin and mucous membranes, or pallor, could indicate, among other things, a lack of oxygen or blood flow. Yellowing of the skin and sclera, known as jaundice, often indicates a liver abnormality. A bluish or dusky tint to the skin, called cyanosis, indicates a critical lack of oxygen, particularly if seen in the face and chest. A flushed face can indicate high blood pressure, exertion, or exposure to cold weather. Key areas to look for skin coloring abnormalities are the lips and mucous membranes and sclera of the eyes (Figure 15.2).

A patient with yellow eyes due to jaundice
Figure 15.2 A patient can present with jaundice with a normal skin tone and yellowing of the eyes. (credit: Sheila J. Toro/Wikimedia Commons, CC BY 4.0)

Patient Behavior

Another vital observation is the behavior of the patient. Calm and relaxed may indicate no acute distress, but many other behaviors may not be considered “inappropriate” depending on the situation. As discussed previously, a patient’s behavior can indicate the health of an individual and alert the nurse to the need for further investigation. Unexpected or atypical behaviors can indicate anything from psychiatric conditions, hypoxic states, infections, or neurological complications. Anxiety can be noted by pacing, fidgeting, or simply an inability to sit still. While restlessness may be a sign of anxiety, it is also an early sign of hypoxia. Other signs of hypoxia and respiratory distress include posturing such as leaning forward with hands on a table, lethargy, inability to ambulate, accessory muscle use, cyanosis, and pallor. It is the nurse’s responsibility to investigate behavior and determine its cause. A depressed individual may avoid eye contact and have a flat affect. There are times when behaviors associated with anxiety, fear, and depression would be expected. Examples of this would include a father in the labor and delivery unit, a spouse who has just lost a partner, or a patient receiving life-altering news.

Age, Gender, and Cultural Variations

Determining the patient’s age, gender, and culture are helpful as a nurse plans care for an individual. An estimate of the patient’s age is gathered through visually assessing the patient’s height, weight, head circumference, and skin tone and presence of wrinkles and comparing the estimate to the actual age. A significant discrepancy between the two may warrant further investigation. A 7-year-old who appears to have the physical features of a toddler would be worrisome as would a 40-year-old who has features making them appear much older in age. Gender and culture observations require further analysis. Many diseases and conditions are linked to biological sex and ethnical backgrounds. For instance, those of Jewish descent are linked to a higher predisposition to Tay-Sachs disease, and those of African descent are predisposed to sickle cell anemia (MedlinePlus, 2021). A patient’s biological sex can identify ways the disease itself affects the body. For instance, although both males and females are equally diagnosed with diabetes, the disease causes a greater risk of coronary artery disease in female patients (Yoshida et al., 2023). Identification of the patient’s biological sex and ethnicity will help the nurse determine if risk factors are present. These topics can be sensitive, and best practice standards indicate for the nurse to ask the patient directly, instead of making assumptions about the biological sex of the patient. It is also vital to be aware and practice in a culturally sensitive manner, but without making assumptions about an individual’s ethnicity and culture. Again, best practice would be to ask patients directly about their specific cultural preferences.

Patient Conversations

How Do You Ask about Cultural Preferences without Assuming a Patient’s Culture?

Scenario: A nurse begins the admission history and assessment on a female who appears to be of Asian descent, one week after she delivered a baby. She is being hospitalized for sepsis.

Nurse: Do you have any past medical history?

Patient: Just a touch of asthma.

Nurse: Any past surgeries?

Patient: Just the C-section a week ago.

Nurse: Can you tell me about any family medical history?

Patient: My dad had colon cancer, and my mom has high cholesterol.

Nurse: Are you currently taking any medications?

Patient: I’ve been taking Tylenol and ibuprofen since I delivered. I haven’t taken those Percocet though since I left the hospital.

Nurse: Okay, that looks like it may be all. I do want to make sure we provide you with the best possible care while you are here. Are there any cultural preferences that you adhere to during this postpartum period?

Patient: Thank you for asking. Yes, we do try to abide by a confinement period for forty-five days and avoid drafts and cold. If possible, I would like the air conditioner turned down and some extra blankets.

Nurse: Absolutely. No problem at all. I will run and grab those blankets now and lower the thermostat.

Scenario follow-up: From this conversation, the nurse was able to address cultural needs while remaining culturally sensitive. The nurse did not make any assumptions regarding the patient’s culture but asked the patient directly and respectfully regarding her cultural preferences.

Growth and Developmental Status

A patient’s growth and development typically follow a relatively standard progression from infancy through adulthood. Periods of rapid physical growth are seen in the young while plateauing should be observed in adulthood, and then potential loss of height in late adulthood. Physical and cognitive development also have periods of rapid gains and slower gains, but there should never be a loss of developmental milestones in healthy individuals, such as walking, talking, and cognition. Growth and development assessments are essential to determine if a patient is progressing through the stages of life as expected and are measured throughout the life span. A patient’s growth is obtained through anthropometric measurements and compared to normal values for the individual’s age.

Development is another objective finding that compares the individual’s physical and cognitive abilities with expected findings for their age. Alterations in growth could indicate hormone deficiencies or conditions that affect the function of the pituitary gland. Alterations in development could indicate cognitive issues or neurological dysfunctions. A child who begins to lose the ability to walk may be evaluated for muscular dystrophy, an incurable and fatal disease. A child who loses the ability to talk or never talks would be evaluated for autism and other genetic conditions. Growth is plotted particularly through weight and height but also includes head circumference for children 3 years old and younger. Development is assessed by both observation and interviewing. Development involves the mastery of developmental tasks in gross motor skills, fine motor skills, speech, and social skills. If there is a concern that development is delayed, typically in children, specific tests may be employed, such as the Denver II Developmental Screening Test.

Cognitive Status

Assessing the cognitive status includes the patient’s level of consciousness, facial expression, speech, and mental acuities. If abnormalities exist, a more in-depth mental examination is needed. The first aspect of cognitive assessment is determination of the patient’s level of consciousness, or their level of awareness and arousal. Assessing and addressing a patient’s pain is also imperative because pain can interfere with the patient’s ability to engage with the nurse’s cognitive assessment. Patients who are alert and with intact cognition should be able to provide the following information:

  • (person) name
  • (place) location
  • (date) day of the week, month, or year
  • (time) general idea of the time of day

If a patient can answer these questions correctly, they are deemed alert and oriented times four—meaning the patient is alert to person, place, date, and time—and this is charted as A&O ×4. If their answers are incorrect, the nurse documents the number of inconsistencies. For instance, a patient who correctly identified name and location but could not identify the time of day, month, weekday, or even year would be charted as A&O ×2. At times, particularly among hospitalized patients, the days may begin to blend together due to the lack of regular sleep schedules, and the patient may be unable to correctly state the date. This does not necessarily mean that the individual is experiencing a change in the level of consciousness. Another question that may help in these instances to thoroughly assess cognition may be why they are hospitalized or being cared for. These four questions, while providing a thorough look at a patient’s cognition, are not always able to be answered by healthy patients. Young children and infants are not expected to answer these questions due to their development.

Patient Conversations

How to Quickly Assess a Patient’s Cognitive Status

Scenario: A nurse working at an emergency department assesses a 51-year-old patient who sustained a head injury from a motorcycle accident.

Nurse: Hello, we are bringing you into the emergency department because you had an accident on your motorcycle. Can you tell me your name?

Patient: Carl. Carl Thomas.

Nurse: Okay, Mr. Thomas. Do you know what day it is?

Patient: Friday.

Nurse: Do you know the time of day?

Patient: Nighttime.

Nurse: And do you know where you are right now?

Patient: The ER.

Nurse: Great, we are going to take good care of you here. Do you remember the accident at all?

Patient: No, the last thing I remembered was driving down the interstate.

Scenario follow-up: From this conversation, the nurse was able to assess that the patient was alert and oriented times four, to person, place, date, and time. This is a critical assessment since the patient sustained a head injury.

Other descriptive terms for a patient’s level of consciousness are lethargic, obtunded, sedated, and comatose. Lethargic means the individual is fatigued, drowsy, and difficult to arouse. Obtunded is used for patients with severe lethargy and lessened response to stimuli. Patients are considered sedated if they are receiving medications to sedate them. A comatose patient is one who is completely unarousable and has no response to stimuli. If a patient is asleep, it may be necessary to wake the patient to determine the level of consciousness, but the nurse may expect a somewhat slower response from patients if they were just awakened. The Glasgow Coma Scale (GCS) is a frequently used scale in nursing to measure a patient’s level of consciousness by assessing eye opening, verbal response, and motor response (Table 15.1). The highest possible GCS score is fifteen, and the lowest is three. A score of fifteen is considered normal, while a score of eight or less is consistent with a severe head injury.

Behavior Response Points
Eyes opening Spontaneously 4
To voice 3
To pain 2
None 1
Verbal response Oriented 5
Confused 4
Inappropriate words 3
Incomprehensible sounds 2
None 1
Motor response Obeys commands 6
Moves to localized pain 5
Withdraws from pain 4
Abnormal flexion 3
Abnormal extension 2
None 1
Table 15.1 Glasgow Coma Scale

In settings where head injuries or neurological conditions are monitored, the nurse will be required to assess and document the patient’s level of consciousness with each vital sign assessment. The Modified Early Warning Score (MEWS) is a measurement tool that analyzes the vital sign data and level of consciousness to provide an early warning for deterioration in the patient’s status (Table 15.2). A normal score is 0 to 1. With a score of two to three, the nurse would increase the frequency of monitoring vital signs to every two hours and may communicate with the healthcare provider if vital signs do not return to normal with the next assessment. A score of four to six would warrant communication with the healthcare provider and hourly vital sign monitoring. With a score of seven, the nurse would activate the rapid response team. A score of eight is a clinical emergency.

Vital Sign 3 2 1 0 1 2 3
Systolic blood pressure (mm Hg) <70 71–80 81–100 101–199   ≥200  
Heart rate (beats per minute)   <40 41–50 51–100 101–110 111–129 ≥130
Respiratory rate (breaths per minute)   <9   9–14 15–20 21–29 ≥30
Temperature   <95°F (<35ºC)   95°F–101.1°F (35ºC–38.4ºC)   ≥101.3°F (≥38.5°C)  
AVPU (alert to voice, to pain, unresponsive)       Alert React to voice React to pain Unresponsive
Glasgow Coma Scale       14–15 10–13 4–9 3
Table 15.2 The Modified Early Warning Score

Other elements used to determine a patient’s cognitive status are assessments of facial expression and speech. An abnormality in one or both may indicate a stroke—or cerebral vascular accident—which is a clinical emergency. The acronym BE FAST allows the nurse to assess for signs and symptoms of stroke quickly and provide immediate treatment to prevent lifelong complications and even death (American Heart Association, 2023). Figure 15.3 shows the mnemonic for assessing for signs of stroke.

Chart showing signs of a stroke with the acronym FAST: Facial drooping, Arm weakness, Speech difficulty, Time to call 911
Figure 15.3 BE FAST is a valuable mnemonic for stroke symptoms and action. (attribution: Copyright Rice University, OpenStax, under CC BY 4.0 license)

Recognition of cognition abnormalities may prompt the nurse to perform a more in-depth neurological or mental health examination to determine the problem or collect more data, such as assessing the cranial nerves or asking about medications and illicit drug use.

Another test used when further evaluation of a patient’s cognitive status is needed is the Mini-Mental State Examination. This examination is a simple thirty-question test that asks the patient to complete several tasks, such as counting, identifying everyday objects, and writing a sentence to measure cognitive ability or decline.

Unfolding Case Study

Unfolding Case Study #3: Part 1

Mrs. Ramirez, a 68-year-old female, is brought to the emergency room by her husband. The patient reports shortness of breath with exertion and feeling “off” for the last three days.

Past Medical History Patient reports shortness of breath “gets worse with walking and only gets better after sitting down for at least fifteen minutes.”
Medical history: Myocardial infarction with stents ten years ago, heart failure, chronic obstructive pulmonary disease (COPD), gastroesophageal reflux disease (GERD), and hypertension.
Family history: Married for fifty years, three grown children. Mother deceased from Alzheimer’s. Father alive, with hypertension and prostate cancer, currently undergoing treatment.
Social history: Former pack/day smoker, quit twenty years ago. Social drinker, one drink/week.
Allergies: None
Current medications:
  • furosemide (Lasix) 40 mg PO daily
  • lisinopril (Zestril) 10 mg PO daily
  • carvedilol (Coreg) 6.25 mg PO twice daily
  • 81 mg aspirin PO daily
Assessment 1000:
General survey: Alert and oriented ×4. Patient appears short of breath and anxious, leaning forward to assist with breathing. Skin is pale.
Recognize cues: Based on the information provided, what findings are most relevant to the patient’s condition and why?
Analyze cues: Based on the recognized cues, what other information should the nurse obtain as part of the general survey?

Nursing Observational and Interviewing Skills

During the first encounter with a patient, the nurse needs to gather pertinent data through vital signs, measurements, observations, and interviewing. To gather the necessary information, the nurse needs to listen to what the patient says, ask appropriate follow-up questions, and observe the patient’s behavior. Observation and interviewing skills are the backbone of the nurse-patient relationship. In fact, they are so valuable that the American Nurses Association (ANA) has included them as one of its eighteen standards of practice (American Nurses Association, 2022).

Nurses must be diligent in attention to both verbal and nonverbal communication expressed by their patients. In addition, nurses must maintain personal awareness of how their own verbal and nonverbal communication is perceived by patients. Utilizing therapeutic communication with patients allows the nurse to delve more deeply into what the patient is saying and helps the patient feel more comfortable with the nurse. It can also help to establish a trusting nurse-patient relationship. For example, if the patient states that they hate it here, a therapeutic response may be, “what aspects of being here do you hate?” or “I am sorry you hate it here. Is there anything I can do to help you feel more comfortable here?” These types of responses are open ended and encourage more dialogue and do not discount the patient’s feelings. If the nurse responded with “a lot of patients have given us great ratings,” communication and the relationship are hindered.

Active Listening

Another critical skill that nurses need to develop and exercise with every patient interaction is active listening, defined as listening with the intent of understanding and discerning. Active listening can help the nurse assess the patient’s situation and concerns. Often, a patient will communicate with the nurse other health concerns that the patient may deem unrelated, but they may actually have a bearing on the treatment plan. These subtle clues may be overlooked if the nurse fails to actively listen. For example, during a first encounter with a patient, there are routine questions a nurse must ask to determine why a patient is seeking care. However, routinely asking these questions of every patient may lead to a nurse simply checking off the task as completed, rather than paying attention to the answers.

It is critical that the nurse use active listening during these conversations. Other times, a patient may go “off script” and begin talking about their family or what happened last year. While this may seem like a rabbit trail for the nurse, the patient could be painting a broader picture of their concerns and adding valuable information that the nurse may have never thought to ask about. The nurse must listen, not just to complete the assigned questions but to understand the patient’s concerns. Active listening also is a building block to a trusting nurse-patient relationship because it encourages engagement from both the nurse and patient.

Adaptive Questioning

Adaptive questioning complements active listening. Questioning that echoes a patient’s comments is called adaptive questioning. When a patient begins discussing something that seems unrelated to the patient’s priority concern, the nurse should follow up with an adaptive question. The best adaptive questions are open ended, not requiring a yes-or-no answer. Adaptive questions could yield information that may have been missed and could even prevent life-threatening consequences. Table 15.3 provides some examples of adaptive questions.

Patient’s Statement Suggested Adaptive Question
“I’m sorry, I wasn’t listening because I am tired today.” “Why do you think you are tired today?”
“I don’t like the food here. It tastes like metal.” “When did you notice your food tasting like metal?”
“Could I get some more gauze? I’m always changing the dressing because of the drainage.” “How often have you been changing the dressing? Have you noticed the color of drainage?”
Table 15.3 Adaptive Questions

Patient Conversations

How to Use Active Listening and Adaptive Questioning during Conversation

Scenario: A nurse working at a family practice clinic escorts an older adult patient with congestive heart failure from the waiting room.

Nurse: Good morning, how are you doing today?

Patient: Busy, as always. My heart condition keeps trying to slow me down, but I just won’t listen.

Nurse: Why do you say that?

Patient: Oh, you know, I get tired easily, and a little short of breath, and my feet have swollen up so much in the last few weeks that I had to buy a shoe the next size up.

Scenario follow-up: Because the nurse was actively listening, the information about the significant swelling was obtained. The nurse may have missed this observation because the patient is wearing shoes. This potentially abnormal symptom requires further investigation by the nurse through adaptive questioning. The main concerns are the worsening of congestive heart failure, such as pulmonary edema.

Nurse: Can you describe the swelling and shortness of breath?

Patient: The swelling’s been getting bad the last few days, even after I have been trying to keep my feet up. It goes all the way up to my knees. I even noticed it a little bit on my hands. I just feel like I am about to burst. I’ve been getting short of breath just taking a shower today and yesterday.

Nurse: Has anything else been bothering you recently?

Patient: I’m just tired. Probably from my stress at work.

Scenario follow-up: From this conversation, the nurse was able to assess that the patient has severe swelling in the legs and feet and some swelling in the hands, fatigue, and shortness of breath. Once these findings are communicated with the healthcare provider, further testing may be required for his condition.

Observation of Nonverbal Communication

Although what a patient says is important, sometimes what is not said can also provide important information. An individual exhibits nonverbal communication through their body language, eye contact, facial expression, and posture. An astute nurse will notice whether the nonverbal communication seems to convey a calm, relaxed disposition or an agitated one. Pain often manifests through nonverbal communication, such as grimacing, restlessness, and guarding movements. The nurse may also be able to tell if the patient is hypoxic simply by observation. Restlessness may be an early sign of hypoxia and should prompt further investigation by the nurse. Observing the patient’s nonverbal communication is a critical component of a complete assessment.

Instruments Used for Assessment

Preparing for a patient’s assessment requires specialized equipment and instruments. During the assessment process, the nurse must observe, listen, and ask pertinent questions. Vital signs, which are temperature, pulse, respiratory rate, blood pressure, and oxygen saturation, must also be obtained to collect essential data needed for the analysis stage. A thermometer, stethoscope, blood pressure cuff, and pulse oximeter are used to obtain vital signs. Since vital sign equipment comes in a variety of sizes, the nurse should verify that the gathered equipment is appropriate for the patient’s age, size, and condition.

To obtain an anthropometric measurement, which is a noninvasive quantitative measurement of the human body, the nurse should have access to the appropriate weight scale and height ruler for the patient. Anthropometry tape and skin calipers may also be gathered to obtain other individual measurements. Commonly obtained anthropometric measurements are height, weight, and body mass index (BMI).

Eyes, Ears, and Touch

The nurses’ observations are invaluable because the nurse is an experienced professional who can identify subtle cues about each patient. They are like detectives who identify areas of concern from a simple conversation. Their eyes for observation, ears for auscultation, and touch for palpation cannot be replaced. Senses associated with eyes, ears, and touch add a completeness to the assessment that cannot be replaced. The eyes are able to observe the patient’s appearance, body language, and behavior. They are also an invaluable tool when counting the respiratory rate. Using the stethoscope, the nurse can assess a beating heart, the patient’s breathing pattern and effort, and the blood pressure. Listening is also done through conversing with patients, ascertaining their perspective on the condition. A handshake or simply applying the blood pressure cuff could let the nurse know the patient’s skin temperature and dryness. Palpation could also highlight areas of abnormalities, such as a mass, localized areas of warmth, or pain. The nurse must palpate the pulse to obtain both the heart rate and the blood pressure.


The stethoscope is a piece of medical equipment used to amplify the body’s internal sounds to its user (Figure 15.4). It is mostly used to listen to the heart, lungs, and bowel sounds, but it is also used to obtain manual blood pressure. A dual-headed stethoscope consists of a diaphragm, a larger, flat circle, and the bell, the smaller, concave-shaped piece. When the nurse wants to hear low-frequency sounds, such as heart sounds, the bell is placed against the patient’s skin. For breath sounds, the diaphragm works best (Figure 15.5).

Stethoscope with parts labeled: Bell, Tubing, Diaphragm, Ear tips, Ear tubes
Figure 15.4 A stethoscope allows a practitioner to hear both the heart and the breath sounds. (attribution: Copyright Rice University, OpenStax, under CC BY 4.0 license)
A doctor using a stethoscope on a patient’s back to assess breathing
Figure 15.5 A healthcare provider uses the diaphragm of a stethoscope to auscultate lung sounds. (credit: US Air Force/Wikimedia Commons, Public Domain)


A thermometer is used to measure body temperature. A variety of formats exist, such as oral, rectal, axillary, tympanic, and temporal. These types of thermometers are discussed in Temperature. The route of temperature measurement is determined based on the patient’s age, cognition, and condition.

Blood Pressure Cuff or Sphygmomanometer

A sphygmomanometer is a blood pressure cuff and is used to obtain a blood pressure reading (Figure 15.6). The blood pressure is the pressure of the blood on the arterial walls during the heart’s contraction and relaxation. The cuff consists of a long fabric portion that is secured with Velcro over the patient’s upper arm. Inside the cuff is an inflatable bladder. With manual blood pressure cuffs, the bladder connects to a bulb that the nurse inflates by squeezing. With the stethoscope in place above the brachial artery, the nurse slowly deflates the bulb as the systolic and diastolic numbers are noted on the dial. The pressure when the first sound is heard over the artery is the systolic blood pressure, while the last sound heard is the diastolic blood pressure. With digital blood pressure cuffs, the bladder connects to a machine and inflates with a touch of a button. After a reading is obtained, the bladder will be deflated.

Manual sphygmomanometer being used to take a patient's blood pressure
Figure 15.6 Using a manual sphygmomanometer and a stethoscope, a nurse can measure a patient’s blood pressure. (credit: Amanda Mills/CDC, Public Domain)

Pulse Oximeter

The pulse oximeter measures the oxygen saturation of the blood and the pulse (Figure 15.7). Once it is placed on or wrapped around the fingertip, a light is emitted from one side through the fingertip and analyzed on the other side. By analyzing the light, the pulse oximeter can determine the saturation of the red blood cells. It can be monitored continuously or periodically, depending on the patient’s condition and healthcare provider’s order. This monitor is either a stand-alone piece of equipment, a component of the vital sign machine, or a component of continuous monitoring used in patient rooms.

Patient’s hand with pulse oximeter attached to finger
Figure 15.7 A handheld pulse oximeter uses a sensor on the patient’s finger to measure blood oxygen. (credit: British Columbia Institute of Technology/CCBY 4.0)

Scale, Height Ruler, Anthropometry Tape, or Skinfold Calipers

Many other types of anthropometric measurements are obtained to determine the overall health of an individual. A scale assesses weight either in kilograms or pounds. In the United States, most people measure their weight in terms of pounds; however, in healthcare, kilograms are often used. It is helpful to be able to convert between the two, that is, to record weight in kilograms and provide the patient with their weight in pounds. One kilogram is 2.2 lb, and 1 lb is 0.45 kg. Height is another measurement that should be obtained. A height ruler is often attached to a standing scale to ease with the attainment of both weight and height. In the United States, most are familiar with measurement of length—and height—in feet and inches, whereas centimeters are used in health care. Rulers used in healthcare provide measurements in both numbers side by side.

Another useful tool to determine body circumferences is anthropometry tape, a flexible measuring tape. For infants and toddlers, it is used to measure serial head and chest circumferences, which are important in tracking proper rate of growth (Figure 15.8). Measuring the waist, hips, and limb circumferences in adults is also helpful to determine the amount of adipose tissue and provide a baseline for further measurements. The waist circumference is a particularly useful measurement of central adiposity. Increased central adiposity increases the risk of heart disease and diabetes (Casadei & Kiel, 2022).

Anthropometric tape being used to measure infant's head circumference
Figure 15.8 Anthropometric tape is used to measure an infant’s head circumference. (credit: Airman st Class Anania Tekurio/Wikimedia Commons, Public Domain)

To assess the thickness of skinfolds at various areas of the body, skinfold calipers may be used (Figure 15.9). Although this measurement is intended to determine nutritional status, measurements with this tool commonly provide inconsistent results, leading to infrequent use. Common sites to measure skinfolds include the back of the upper arm, hips, abdomen, thighs, and chest (Casadei & Kiel, 2022).

Skin fold calipers
Figure 15.9 Skinfold calipers include measurements in both inches and millimeters. (attribution: Copyright Rice University, OpenStax, under CC BY 4.0 license)

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