Measuring Vital Signs
Source: Meghan Fashjian, ACNP-BC, Beth Israel Deaconess Medical Center, Boston MA
The vital signs are objective measurements of a patient's clinical s…
Make sure the patient has been seated and resting for at least 5 minutes prior to obtaining vital signs (VS) to accurately determine the baseline.
1. Heart rate
The radial artery is the most common site used to assess the pulse.
- Explain to the patient that you are going to start by checking their pulse.
- Place your index and middle fingers on the radial pulse (never use the thumb, as you can sometimes feel your own pulse). To prevent occlusion, do not press or apply pressure to the artery.
- Assess the rhythm.
- If the rhythm is regular, count the beats for 15 seconds, then multiply by 4.
- If the rhythm is irregular, count the beats for a full 60 seconds. A regularly irregular pulse may signal premature beats, whereas an irregularly irregular rhythm may signal atrial fibrillation. Confirm any abnormalities with an electrocardiogram (ECG).
- Note the amplitude of the pulse (normal, bounding, diminished, or absent). Bounding pulses may be observed at rest with atherosclerosis, congestive heart failure (CHF), kidney disease, aortic insufficiency, or fever. Diminished pulses may be noted with peripheral vascular disease (PVD) or sepsis. If absent, it may be due to occlusion of the artery and should be further investigated.
- Record HR, making a note of rhythm and amplitude on the VS flow sheet.
2. Respiratory rate
Attempt to calculate the respiratory rate without the patient becoming aware. This can be done either by leaving the fingers on the patient's radial pulse or by counting during the cardiovascular portion of the physical exam when they are breathing normally.
- Count the respiratory rate for a full 60 seconds. One respiratory cycle includes both inspiration and expiration. Note if slow breathing (bradypnea) or rapid shallow breathing (tachypnea) is present.
- Assess the regularity of breathing. Note if an irregularly irregular (ataxic or Biot's) or regularly irregular (Cheyne-Stokes, characterized by long periods of apnea) pattern is present.
- Note the depth of breathing. Is the patient engaged in shallow or very deep breathing? For example, rapid shallow breathing can be labeled as tachypnea, whereas deep rapid breathing may be the Kussmaul breathing, which is associated with diabetic ketoacidosis.
- Note the work of breathing. Is the patient utilizing accessory muscles with respiration? These include the trapezius, scalene, sternomastoid, and external intercostal muscles. This often indicates if there is an issue with oxygen delivery or air trapping.
- Record the rate and rhythm on the VS flow sheet. Also include depth and work of breathing, if abnormal.
3. Temperature
An examiner can obtain oral, rectal, axillary, or tympanic membrane temperatures. Be familiar with the differences in the expected normal values. In the office setting, the most common method of checking the temperature is oral. If the patient is non-responsive or unable to cooperate, oral is not the preferred method, and the examiner should use an alternate technique.
- Explain to the patient that you are going to check their temperature.
- Place a disposable plastic sheath on the thermometer.
- If using a digital thermometer, insert under the patient's tongue and hold there until the thermometer alerts you that the temperature has been calculated.
- If using a glass thermometer, make sure it reads less than 96 °F and insert under the patient's tongue. Hold there for 3 min.
- Record the temperature and location obtained on the vital sign flow sheet.
4. Oxygen saturation
The oxygen saturation (SaO2) can be measured by a non-invasive method called pulse oximetry. The oximeter is a small, usually portable, device that consists of a monitor and a probe, which is placed on the patient's finger, toe, or earlobe. The probe allows two wavelengths of light to pass through the body to a photodetector. The changes in absorbance indicate the percentage of saturated hemoglobin in the arterial blood. Most oximeters display the patient's pulse rate, too. Be advised: if a patient's fingertip is cold or if the patient is wearing nail polish, this may interfere with the reading. There are also conditions that falsely elevate the readings including carbon monoxide poisoning.
- Explain to the patient that you are going to check their oxygen saturation.
- Place the oximeter probe onto the patient's finger. Finger probes are often a single rubber piece that can be hinged and slipped onto the fingertip. There are alternative probes that can be placed on other body parts, if unable to obtain a read from the finger.
- Record the oximeter reading on the vital sign flow sheet.
5. Pain
In most instances , a numeric scale (1-10, 10 being the worst pain imaginable) is utilized to estimate presence and the level of pain. In non-verbal patients, children, or those who do not speak English, severity of pain is assessed by using the visual Wong-Baker FACES® scale. Always remember to reassess pain after any intervention taken.
- Ask the patient if they are having pain.
- If the patient expresses comprehension and does have pain, ask them to quantify it on a scale of 1-10.
- If the patient is unable to comprehend, but appears to have pain, show them the Wong-Baker FACES® scale to determine the severity of pain.
- Record on the vital sign flow sheet.
Make sure the patient has been seated and resting for at least 5 minutes prior to obtaining vital signs (VS) to accurately determine the baseline.
1. Heart rate
The radial artery is the most common site used to assess the pulse.
- Explain to the patient that you are going to start by checking their pulse.
- Place your index and middle fingers on the radial pulse (never use the thumb, as you can sometimes feel your own pulse). To prevent occlusion, do not press or apply pressure to the artery.
- Assess the rhythm.
- If the rhythm is regular, count the beats for 15 seconds, then multiply by 4.
- If the rhythm is irregular, count the beats for a full 60 seconds. A regularly irregular pulse may signal premature beats, whereas an irregularly irregular rhythm may signal atrial fibrillation. Confirm any abnormalities with an electrocardiogram (ECG).
- Note the amplitude of the pulse (normal, bounding, diminished, or absent). Bounding pulses may be observed at rest with atherosclerosis, congestive heart failure (CHF), kidney disease, aortic insufficiency, or fever. Diminished pulses may be noted with peripheral vascular disease (PVD) or sepsis. If absent, it may be due to occlusion of the artery and should be further investigated.
- Record HR, making a note of rhythm and amplitude on the VS flow sheet.
2. Respiratory rate
Attempt to calculate the respiratory rate without the patient becoming aware. This can be done either by leaving the fingers on the patient's radial pulse or by counting during the cardiovascular portion of the physical exam when they are breathing normally.
- Count the respiratory rate for a full 60 seconds. One respiratory cycle includes both inspiration and expiration. Note if slow breathing (bradypnea) or rapid shallow breathing (tachypnea) is present.
- Assess the regularity of breathing. Note if an irregularly irregular (ataxic or Biot's) or regularly irregular (Cheyne-Stokes, characterized by long periods of apnea) pattern is present.
- Note the depth of breathing. Is the patient engaged in shallow or very deep breathing? For example, rapid shallow breathing can be labeled as tachypnea, whereas deep rapid breathing may be the Kussmaul breathing, which is associated with diabetic ketoacidosis.
- Note the work of breathing. Is the patient utilizing accessory muscles with respiration? These include the trapezius, scalene, sternomastoid, and external intercostal muscles. This often indicates if there is an issue with oxygen delivery or air trapping.
- Record the rate and rhythm on the VS flow sheet. Also include depth and work of breathing, if abnormal.
3. Temperature
An examiner can obtain oral, rectal, axillary, or tympanic membrane temperatures. Be familiar with the differences in the expected normal values. In the office setting, the most common method of checking the temperature is oral. If the patient is non-responsive or unable to cooperate, oral is not the preferred method, and the examiner should use an alternate technique.
- Explain to the patient that you are going to check their temperature.
- Place a disposable plastic sheath on the thermometer.
- If using a digital thermometer, insert under the patient's tongue and hold there until the thermometer alerts you that the temperature has been calculated.
- If using a glass thermometer, make sure it reads less than 96 °F and insert under the patient's tongue. Hold there for 3 min.
- Record the temperature and location obtained on the vital sign flow sheet.
4. Oxygen saturation
The oxygen saturation (SaO2) can be measured by a non-invasive method called pulse oximetry. The oximeter is a small, usually portable, device that consists of a monitor and a probe, which is placed on the patient's finger, toe, or earlobe. The probe allows two wavelengths of light to pass through the body to a photodetector. The changes in absorbance indicate the percentage of saturated hemoglobin in the arterial blood. Most oximeters display the patient's pulse rate, too. Be advised: if a patient's fingertip is cold or if the patient is wearing nail polish, this may interfere with the reading. There are also conditions that falsely elevate the readings including carbon monoxide poisoning.
- Explain to the patient that you are going to check their oxygen saturation.
- Place the oximeter probe onto the patient's finger. Finger probes are often a single rubber piece that can be hinged and slipped onto the fingertip. There are alternative probes that can be placed on other body parts, if unable to obtain a read from the finger.
- Record the oximeter reading on the vital sign flow sheet.
5. Pain
In most instances , a numeric scale (1-10, 10 being the worst pain imaginable) is utilized to estimate presence and the level of pain. In non-verbal patients, children, or those who do not speak English, severity of pain is assessed by using the visual Wong-Baker FACES® scale. Always remember to reassess pain after any intervention taken.
- Ask the patient if they are having pain.
- If the patient expresses comprehension and does have pain, ask them to quantify it on a scale of 1-10.
- If the patient is unable to comprehend, but appears to have pain, show them the Wong-Baker FACES® scale to determine the severity of pain.
- Record on the vital sign flow sheet.
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Q1: What are the five commonly accepted vital signs?
The five commonly accepted vital signs are blood pressure, heart rate, temperature, respiratory rate, and oxygen saturation. These objective measurements provide critical information about a patient's clinical status. In many clinical practices, pain is also documented as a sixth vital sign, though it differs from the others because it is subjective rather than objective.
Q2: What are the normal ranges for heart rate, respiratory rate, and oxygen saturation?
Normal heart rate ranges from 60-100 beats per minute, while respiratory rate should be 12-20 breaths per minute. Oxygen saturation typically falls between 95-100%. Average oral temperature is approximately 98.6°F (37°C). These ranges serve as reference points, but each patient should be evaluated individually within their complete clinical context.
Q3: How does temperature vary by measurement location?
Temperature measurements vary depending on where they are taken. Rectal and tympanic temperatures average approximately 1°F higher than oral temperature, while axillary (armpit) temperature averages about 1°F lower than oral measurement. Understanding these differences ensures accurate interpretation of patient temperature data across different measurement sites.
Q4: Why is pain considered a vital sign in clinical practice?
Pain is documented as a sixth vital sign in many practices because it provides essential information about patient status. However, unlike the other five vital signs, pain is a subjective measurement that varies according to each individual patient's perception and tolerance. Regular pain documentation in the same location as other vital signs ensures consistent monitoring.
Q5: What role do vital signs play in patient assessment?
Vital signs serve as the first clue that something may be amiss with a patient, especially when the patient cannot communicate their symptoms. These objective measurements provide immediate insight into clinical status. However, vital signs should never be interpreted in isolation; they must be considered alongside the entire clinical picture for accurate assessment.
Q6: Why should normal vital sign ranges be interpreted individually for each patient?
Although quoted normal ranges exist for vital signs, each patient must be considered as an individual rather than treated according to standard ranges alone. A patient's baseline, age, medical history, and current clinical context all influence what constitutes normal for that specific person. Individualized assessment prevents misinterpretation and ensures appropriate clinical decision-making.
Q7: What does the vital signs assessment include?
The vital signs assessment includes estimation of heart rate, blood pressure, respiratory rate, temperature, oxygen saturation, and evaluation of pain presence and severity. This comprehensive evaluation provides objective measurements of a patient's clinical status and helps identify potential health concerns. Each component contributes essential information to the overall clinical picture.