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Vital signs are objective measurements of a patient’s clinical status. The commonly documented vital signs are blood pressure, heart rate, temperature, respiratory rate, oxygen saturation and the presence and severity of pain.

The principles and procedure of blood pressure measurement have been covered in detail in another video of this collection. Here, we will illustrate how to measure and record the rest of the vital signs.

Before starting with the procedure, ensure that the patient has been seated and resting for at least 5 minutes. In the meantime, wash your hands thoroughly with soap and warm water. Upon entering the room, introduce yourself to the patient, briefly explain what you are going to do, and obtain their consent, “Now I am going to check your vital signs, will that okay?”

Start by assessing the heart rate also known as the pulse rate. The radial artery is the most common site used to assess this parameter. Place your index and middle fingers on the radial pulse. Do not apply pressure, and never use the thumb, as with thumb you may sometimes feel your own pulse. Assess the rhythm and note if it is regular. Count the beats for 15 seconds, and then multiply by 4 to calculate the pulse rate in beats per minute. If the rhythm is irregular, count the beats for a full minute. Simultaneously, assess the amplitude of the pulse, and note whether it is normal, bounding, diminished, or absent. Record the heart rate, making a note of the rhythm and amplitude on the vital signs flow sheet. The accepted range for a normal heart rate is 50-80 beats per minute.

The next vital sign to be recorded is the respiratory rate. Attempt to calculate this without the patient becoming aware. Count the respiratory cycles for at least one full minute. One respiratory cycle includes both inspiration and expiration. Note the rate, regularity, depth, and work of breathing. The work of breathing refers to the utilization of accessory muscles of respiration. These include neck muscles like scalene and sternomastoid. The constant utilization of these muscles indicates difficulty with breathing. Record the rate and rhythm on the vital signs sheet. Also include the depth and work of breathing, if abnormal. The normal respiratory rate is about 14 to 20 breaths per minute.

After obtaining the respiratory rate, check the temperature, most commonly done by using a digital oral thermometer. Place a disposable plastic sheath on the thermometer, and insert it under the patient’s tongue and hold there until the thermometer alerts you that the temperature has been calculated. Other than the oral temperature, an examiner can obtain axillary, rectal, or tympanic membrane temperatures. However, remember that there is a difference in the expected normal values based on the location. Record the temperature and the location where it was obtained.

Next, measure the oxygen saturation, commonly known as SaO2, which refers to the fraction of oxygen-saturated hemoglobin relative to total hemoglobin. This can be measured by a non-invasive method called pulse oximetry. The pulse oximeter is a small, usually portable device that consists of a monitor and a probe, which is usually placed on the patient’s finger. One side of the probe has the light sources, which emit two different types of lights-infrared and red, which are transmitted through the finger to the detector on the other side. The oxygen-rich hemoglobin absorbs more of the infrared light and the deoxygenated hemoglobin absorbs more of the red light. The microprocessor calculates the differences and converts the information into a digital readout of the percentage oxygen-saturated hemoglobin in the arterial blood, which is nothing but SaO2. To obtain this value, simply place the oximeter probe, which is often a single rubber piece that can be hinged and slipped onto the patient’s fingertip. After a few seconds, record the display reading, which should normally be more than 92 percent. In case if the patient’s fingertip is cold or if the patient is wearing nail polish, which might interfere with the fingertip reading, consider using a probe for the ear lobe.

Lastly, ask the patient if they are experiencing any type of pain. If the patient expresses comprehension and does have pain, ask them to quantify it on a scale. 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.

You’ve just watched JoVE’s demonstration of the principles and procedures associated with obtaining the commonly required vital signs.

These simple non-invasive measurements provide essential insight into a patient’s clinical status, as they can indicate early objective changes prior to the onset of symptoms. Therefore, every examiner should be aware about the methods used to record these and the accepted variations in the readings. As always, thanks for watching!