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Definition: Vital Sign from Black's Medical Dictionary, 42nd Edition

One meaning is the indication that an individual is still alive. Chest movements (resulting from respiration), the existence of a pulse (showing that the heart is still beating) and constriction of the pupil of the eye in response to bright light are all vital signs. Another meaning is the group of routine monitoring tests performed by nurses, that is measurements of pulse, respiratory rate and body temperature.


Summary Article: VITAL SIGNS from NURSING: The Ultimate Study Guide

Vital signs, by definition, are a person’s temperature, pulse, respiration rate, and blood pressure (BP). These signs reflect the status of a person’s circulatory, respiratory, neurological, and endocrine functions. You will need to become familiar with these signs and practice obtaining accurate results. In this course, you will have plenty of time to practice on other students and those attractive-looking manikins. At the end of the semester, you will go to a health care facility where you will be able to practice these skills on real patients.

Time for a funny story that I know some of you will relate to. I was almost done with my Fundamentals course and was at a local hospital where I had to practice on my very first patient. I was assessing the man’s vital signs and obtaining the correct results. I felt comfortable and confident because I thought I was doing so well. When I exited the room, one of the nurses walked up to me and asked, “Did you take his temperature with the red thermometer?” My response was yes. She went on to tell me: “Though the thermometer was clean, all red thermometers are for rectal temperatures.” Well, that just turned my confidence into pure embarrassment. It’s so true what they say about learning from your mistakes, because believe me, I never made that mistake again. So always remember, when you see a red thermometer, red stands for “rectal.” With that said, let’s move on.

Body Temperature
  • Definition: Body temperature is the balance between the productions of heat in the body, which is measured in degrees. The body’s temperature is controlled by the hypothalamus. This is in the preoptic part of the brain. The hypothalamus is able to detect when the body’s temperature is too high, indicating a fever, or too low, indicating hypothermia. A normal temperature is 98.6 °F (36 °C).
  • Assessing Body Temperature: The four main ways to assess body temperature are (a) orally, (b) rectally (this is the most reliable method), (c) axillary (i.e., under the arm; this is used mostly with newborns), and (d) tympanically (which indicates core body temperature). Many hospitals use electronic thermometers or infrared tympanic thermometers. Rectal temperatures are not used on patients who are immunocompromised. When taking oral temperatures, make sure that the patient has not had anything to eat or drink 15 minutes before the assessment. Cold or hot liquids or food content can alter the temperature.
  • Factors That Affect Temperature: Age, exercise, stress, illness, and infection are all factors that can affect temperature.
  • Temperature Gone Wrong: In your training, you will come across words such as pyrexia, hyperpyrexia, and hypothermia. Pyrexia means that the temperature is above the normal level. Hyperpyrexia is a very high fever, with an elevation in temperature greater than 105.8 °F. Hypothermia is the opposite of both of these terms; the patients usually present as having a temperature lower than average.
Pulse
  • Definition: A pulse is caused by the amount of blood being pumped by the left ventricle of the heart. The heart expels about 5 L of blood per minute. This would be a great time to look over your A&P textbook. Remember the term cardiac output? You can apply this process to the pulse. The normal adult pulse ranges from 60 to 100 beats per minute (bpm).
  • Assessing the Pulse: There are many sites on the human body where you can auscultate, or palpate, a pulse. The apical pulse , located between fourth and fifth left intercostal space, is the most accurate site at which to measure a rhythm. Other sites include temporal (over the temporal bone of the head), brachial (at the antecubital fossa), radial (below the thumb, at the wrist), carotid (at the sides of neck), popliteal (behind the knee), femoral (in the inguinal area), posterior tibial (at the inner ankle), and pedal (along the top of the foot).
  • Factors That Affect Pulse: Age, gender, exercise, medications, stress, anxiety, position changes, illness, and loss of blood can cause alterations in a pulse rate and rhythm. Infants have a higher pulse rate; a rate of 110 to 160 bpm is common. School-age children may have a pulse rate of approximately 75 to 120 bpm.
  • Pulse Gone Wrong: Become familiar with the terms that describe alteration in pulse. They will be used frequently not only when describing a pulse but also when reading electrocardiogram (EKG) strips depicting a patient’s heart rhythm. Tachycardia means an increase or higher than normal pulse rate. Bradycardia is a pulse rate less than normal or less than 60 bpm. Dysrhythmia is an irregular pulse pattern that is usually shown on an EKG. Patients with dysrhythmia are usually placed on telemetry—a continuous cardiac monitor—to monitor these irregular heartbeats.
Respiration
  • Definition: Gas exchange is the changing of carbon dioxide into oxygen in the lungs. It is the body’s way of regulating the necessary amount of oxygen in the circulating blood to maintain healthy cells. Here is a little exercise: Take a deep breath (called inspiration), and now exhale (a more technical term is exhalation). A normal respiratory rate is 16 to 20 breaths per minute. This can vary on the basis of the patient’s condition.
  • Assessing Respiration: The first step in evaluating a patient’s respiration is to assess him or her visually; note if the patient is having any problems breathing, such as using his or her accessory muscles (chest muscles used to draw in breath/inhale). Ask if the patient has a history of any respiratory problems. After visual assessment, auscultate or listen to the patient’s breathing pattern by placing the stethoscope over the diaphragm or by simply looking at the movement of the chest. An easy way to determine the respiration rate is by counting the number of breaths for 30 seconds then multiplying by 2 to get a full-minute rate.
  • Factors That Affect Respiration: Smoking, stress, anxiety, exercise, temperature, infection, pneumonia, and medications all affect respiration, and the list goes on. It is important to document and report these variables. Here is one of the biggest secrets that I am going to tell you: For any respiration-related multiple-choice question that you have on an exam, always choose the answer in which the breathing is disrupted! Choose answers that coincide with “ABC” (airway, breathing, and circulation).
  • Respiration Gone Wrong: An increase in respiration rate is defined as tachypnea (more than 20 breaths per minute). A decrease in respiration rate is defined as bradypnea (fewer than 12 breaths per minute). Remember that the ending -pnea represents an alteration in breathing. I don’t know about you, but with all this information, my respirations are changing!
Blood Pressure
  • Definition: Blood pressure (BP) is the force of blood against the wall of the left ventricle of the heart. For all you visual learners, picture a waterslide of blood pushing against the arterial walls. You probably are familiar with the terms systolic and diastolic. The systolic BP is the first number obtained when assessing the BP; the measurement determines the heart’s ability to contract. The diastolic BP is the second number, which signifies the relaxation of the heart. Normal BP is anything less than 120/80 mmHg.
  • Assessing the Blood Pressure: BP is measured using a BP cuff, a sphygmomanometer (that’s a funny word), and a stethoscope. One of your textbooks likely will have a picture of this equipment or, even better, go to the lab and practice. The cuff should be placed in two-thirds length of the upper arm and cover three-fourths circumference of the arm. The sounds that you hear are called Korotkoff sounds, which represent the diastolic and systolic BP. When measuring someone’s BP, don’t leave the cuff inflated on the patient too long; this can be very uncomfortable. Also, if you do not get an accurate reading the first time, try again. Ask the patient his or her normal BP range; that way, you will be aware of any significant changes.
  • Blood Pressure Gone Wrong: I discuss hypertension in further detail in Chapter 3, but I offer a quick definition here: any BP that is greater than 120/80 mmHg. Hypotension is anything less than 120/80 mmHg. It can be caused by medications, hemorrhage, or hypovolemia (decreased body fluid volume). A decrease in BP can also be caused by a change in position (e.g., moving quickly from a sitting to a standing position); this is called orthostatic hypotension. This is a safety issue, because hypotension can cause a person to become very dizzy. If your patient has orthostatic hypotension, make sure you help him or her stand and have him or her change positions slowly.

That pretty much wraps up vital signs and their measurement. I cannot stress enough the importance of practicing these skills. It may be difficult at first, but with a little practice, you will become an expert.

Copyright © 2011 Springer Publishing Company

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