Assessing Body Temperature

  • There are four sites for measuring body temperature, these includes Oral, Rectal, Axillary, and Tympanic membrane. Assessing body temperature is a nursing procedure that provide a baseline data for subsequent evaluation and nurses to determine changes in the core temperature of patient in response to a specific medical intervention such giving an antipyretic drug, a therapy and minor or invasive procedure.
 Four Sites Used for Body Temperature Assessment
Assessing Body Temperature
  1. Oral. This site is frequently used because it is very convenient and accessible. Food, fluids, or warm smoke can affects mouth temperature. If in case that patient has just ingested hot or cold food, wait 30 minutes before talking a temperature orally. Do not take oral temperature for patient who just undergone oral surgery to prevent injury. The proper placement of thermometer bulb is on either side of the frenulum (small fold of integument or mucous membrane).
  2. Rectal. This site is considered to be very accurate but inconvenient and unpleasant for patients. It is difficult for patient who cannot turn to the side. Taking temperature rectally is contraindicated for patient with MI or Myocardial Infarction. Inserting a rectal temperature can produce vagal stimulation which results   myocardial damage. Rectal temperatures are contraindicated for patients with diarrhea, immunosupressed, with rectal disease, have a clotting disorder, haemorrhoids and who are undergoing rectal operation. Before performing this method, use clean glove and instruct the patient to take a slow deep breath during insertion. Never force the thermometer if you felt resistance. For adults, insert 3.5 cm or 1 1/2 inch.
  3. Axilla. It is safe and noninvasive and is preferred site for measuring temperature in newborn. Axillary method is inaccurate as some research said. To obtain an accurate measurement using this method, make sure you left the thermometer in place a long time. This method is appropriate to those patients with oral inflammation or wired jaw, who cannot breathe through their nose, and recovering from oral surgery. The proper placement of bulb is in the center of the axilla. Pat the armpit dry with tissue or ask patient to do it if able. Moisture can affect the reading.
  4. Tympanic membrane. It reflects our core body temperature which abundant of arterial blood supply. This method is readily accessible and very fast because it uses sensors that applied directly to the tympanic membrane.
Inserting a Tympanic Thermometer:
  • Adult = Pull the pinna slightly upward and backward. Point the probe slightly anteriorly, toward the eardrum. Insert the probe slowly using a circular motion until snug.
  • Infant = Pull the pinna straight back and slightly downward. Direct the probe tip anteriorly and insert as far as enough to seal the canal.
  • Over 3 years old = Pull the pinna of the ear back and up.
  • Under 3 years old = Pull the pinna of the ear back and down
Types of Thermometer
  1. Mercury-in-glass Thermometers. It is very hazardous because it is made of glass and toxic chemical inside called mercury. The use of mercury-in-glass thermometer was eliminated in 1988 and no longer exists in health care environment. There are three types of thermometer tips, long, short, slender or rounded tips.
  2. Electronic Thermometer. This thermometer can provide a temperature reading in just 2 to 60 seconds. It is often called digital thermometer because they display a numeric values. It consists of a battery-operated portable electronic unit, a probe, and a disposable probe cover.
  3. Chemical Disposal Thermometer. It is another method of assessing body temperature which uses a liquid crystal dots or bars or heat-sensitive tape or patches that is applied to the forehead. To able to read the temperature, notes the highest reading among the dots that have changed color.
  4. Temperature-sensitive Tape. It obtains only your body surface temperature and does not indicate the core temperature. The tape is applied to the skin, forehead and abdomen. Inside the tape is a liquid crystals that change color according to temperature.
  5. Infrared Thermometer. Infrared (tympanic) thermometer is an example, which senses a body in the form on infrared energy given off by a heat source.
 How to Convert Degree Celsius to Fahrenheit, or vise versa?
  • Our body temperature is measured in heat called degrees on two scales, the Celsius and Fahrenheit. The basic conversion of temperature is very important in clinical settings.
  • To convert from Fahrenheit to Celsius just deduct 32 from the Fahrenheit and then multiply by 5/9:
C= (Degree Fahrenheit – 32) X 5/9
  •  To convert from Celsius to Fahrenheit, multiply the Celsius by 9/5 and then add 32:
F= (Degree Celsius X 9/5) + 32