Body Temperature Measurement Sites

The oral cavity (under the tongue) is the most common site for measuring body temperature. Caution should be taken to prevent inaccurate readings if hot or cold foods have been ingested (wait 20 to 30 minutes) or if the client has been smoking. Alternative sites such as the ear (tympanic membrane) or axilla (armpit) should be used when the client’s safety is a consideration. For example, unconscious clients, infants, small children, or cognitively challenged clients may have difficulty with the oral thermometer under the tongue or may bite the thermometer and break it.

Thermometers

Four types of thermometers are available for measuring body temperature (Table 11-2 and Figures 11-2 to 11-7). Disposable plastic sheaths are used over the probe end of the thermometer as a protective barrier for infection control. Electronic and the mercury-in-glass thermometers are commonly used at home and in professional practice. The mercury-in-glass thermometer (see Figure 11-2) must be handled carefully to avoid breakage and inadvertent spillage of the contents. If a mercury-in-glass thermometer is broken, it should be cleaned up immediately to prevent mercury contamination or poisoning (Box 11-3).

TABLE 11-2 Types of Thermometers for Measuring Body Temperature

Figure 11-2 Types of mercury-in-glass thermometers. A, Oral. B, Oral, rectal, or axillary. C, Rectal.

(From Potter PA, Perry AG: Fundamentals of nursing, ed 7, St Louis, 2009, Mosby.)

Figure 11-3 Electronic (digital) thermometer.

(Courtesy Sedation Resource, Lone Oak, Texas, www.sedationresource.com.)

Figure 11-4 Electronic thermometer. Blue probe is for oral or axillary use. Red probe is for rectal use.

(From Potter PA, Perry AG: Fundamentals of nursing, ed 7, St Louis, 2009, Mosby.)

Figure 11-5 A, Electronic pacifier thermometer. B, Underarm (axillary), oral, and rectal electronic thermometer.

Figure 11-6 Tympanic membrane thermometer.

(From Potter PA, Perry AG: Fundamentals of nursing, ed 7, St Louis, 2009, Mosby.)

Figure 11-7 Disposable, single-use thermometer strip.

(From Potter PA, Perry AG: Fundamentals of nursing, ed 7, St Louis, 2009, Mosby.)

Electronic (digital) thermometers consist of a probe attached to a digital readout (see Figures 11-3 and 11-4) to measure oral and axillary temperatures. A pacifier thermometer (see Figure 11-5), a type of electronic thermometer, obtains a reasonably accurate reading in younger children within 3 minutes. Underarm (axillary) electronic thermometers (see Figure 11-5), relatively new on the market, have a short reading time (8 to 30 seconds) and are easy to use in young children. Tympanic membrane (ear) thermometers (see Figure 11-6) are easy to use, less invasive, and achieve a reading within seconds. Oral and axillary disposable, single-use thermometers can indicate a client’s temperature within 70 seconds (see Figure 11-7). Disposable single-use thermometers are used mostly for oral temperature screening. See Procedures 11-1 and 11-2 for taking basal body temperature orally using two different types of thermometers. Temperature is recorded in degrees Fahrenheit.

Decision Making Based on Observed Temperature

Usually a high body temperature (known as fever or pyrexia) indicates that the body is fighting an infection. If the client’s temperature exceeds 99.6° degrees Fahrenheit (or 37.5° Celsius), the client should be evaluated for causative factors (see Table 11-1). If the client’s temperature is 104° Fahrenheit (or 40° Celsius) or higher and the infection is not dentally related, a physician’s referral is indicated. If pyrexia is due to a dental infection, then immediate dental treatment and antibiotic therapy may be indicated. A body temperature of 105.8° F (41° Celsius) indicates a medical emergency, so the EMS system would be activated. Low body temperature can occur with cold exposure, endocrine disorders, sepsis, alcohol intake, eating disorders, and neurologic and neuromuscular disorders.

Pulse Measurement Sites

Pulse points are body sites where the rhythmic beats of an artery can be felt. The most common site for assessing the radial pulse is the thumb side of the inner wrist where the radial artery can be felt (Figure 11-8, Procedure 11-3). The fingertips of the first two fingers are used to feel for the pulse (a throbbing sensation). (Note: Never use the thumb to feel for the pulse, because it has a pulse of its own that can be mistaken for the client’s.) If the radial pulse cannot be felt, the carotid pulse, located on the side of the neck over the carotid artery, is an alternative. In emergency situations the carotid pulse should be palpated because the body delivers blood to the brain for as long as possible, whereas peripheral blood supply can decline. The pulse is recorded in BPM. Heart rhythm (regular or irregular) and pulse quality (thready, strong, bounding, or weak) also are assessed when the pulse is measured.

Figure 11-8 Position of the fingers in measuring the radial pulse.

(From Potter PA, Perry AG: Fundamentals of nursing, ed 7, St Louis, 2009, Mosby.)

Decision Making Based on Observed Pulse Rate

If the adult client’s heart rate falls under 60 BPM or rises above 100 BPM, the client should be evaluated for causative factors or conditions. If no cause can be determined, a medical consultation with the client’s physician should be conducted.

A medical consultation is recommended in the following circumstances:

If a client with risk factors for coronary artery disease is experiencing five or more premature ventricular contractions (PVCs) per minute. A PVC is a break, or skip, in the normal rhythm, and the dental hygienist will detect an interruption in successive pulse waves.

If the client is experiencing pulsus alternans, alternating strong and weak heartbeats, which may indicate ventricular failure, high blood pressure, or coronary heart disease.

A full, bounding pulse may indicate high blood pressure. A weak, thready pulse usually is found in persons with hypotension and is a sign of shock.

Respiration Measurement Site

Respiration rate may be measured before or after the client’s pulse rate is assessed. The dental hygienist’s hand remains on the client’s radial pulse while the hygienist inconspicuously counts the rise and fall of the client’s chest.

Normal adult range is 16 to 18 RPM. Children have a more rapid respiratory rate (20 to 30 RPM) than that of adults. Young children also tend to have a less regular breathing cycle. Advancing age produces an increase in the respiration rate. Steps for measuring respirations are shown in Procedure 11-4.

Decision Making Based on Observed Respiration

If an abnormal respiratory rate is detected, the dental hygienist refers the client to the physician of record for a medical evaluation. Table 11-5 presents acceptable ranges of respiratory rates by age. Tachypnea (rapid shallow breathing) greater than 20 RPM may indicate restrictive lung disease or inflammation of the lungs. Hyperpnea (hyperventilation or rapid deep breathing) may be associated with physical exercise, anxiety, or metabolic acidosis. Bradypnea (slow breathing) may occur with diabetic coma. Obstructed breathing from narrowed airways may occur with asthma, chronic bronchitis, congestive heart disease, and chronic obstructive pulmonary disease.

TABLE 11-5 Acceptable Ranges of Respiratory Rate According to Age

From Potter PA, Perry AG: Fundamentals of nursing, ed 7, St Louis, 2009, Mosby.

Decision Making Based on Observed Blood Pressure

Hypertension is the major cause of stroke and is a contributing factor for myocardial infarction (heart attack). Although not a disease category, prehypertension identifies clients who should be counseled to adopt a healthier lifestyle to reduce blood pressure or prevent hypertension entirely. Clients who are prehypertensive are not candidates for drug therapy unless risk factors for hypertension (e.g., diabetes and kidney disease) are present and only after lifestyle modifications fail to reduce the blood pressure to <130/80 mm Hg.

A medical consultation is indicated for persons with abnormal blood pressure (Tables 11-8 and 11-9) before administration of dental or dental hygiene care.

TABLE 11-8 Classification of Blood Pressure for Adults

National Institutes of Health (NIH): The seventh report of the Joint National Committee on Detection, Evaluation, and Treatment of High Blood Pressure, Bethesda, Md, 2004, NIH.

∗ Based on average of two or more properly measured, seated, blood pressure readings on each of two or more office visits.

† Note that if 160-179/100-109, routine dental care can be provided, but treatment should be delayed if care will be stressful or if client cannot handle stress. If local anesthesia is required, use 1:100,000 vasoconstrictor. If ≥180/≥110, delay treatment until blood pressure is controlled. If emergency dental care is needed, care should be provided in a hospital dental clinic where emergency life support personnel and equipment are located.

TABLE 11-9 Adult Blood Pressure Guidelines Used in the Dental Hygiene Process of Care

∗ See Chapter 10 for an explanation of ASA Physical Status Classification.

† When the blood pressure is slightly above the cutoff for category IV and when anxiety is present, the use of inhalation sedation may diminish the blood pressure (via the elimination of stress) below the 200/115 level. The client should be advised that if the nitrous oxide and oxygen succeeds in decreasing the blood pressure below this level, the planned treatment can proceed. However, if the blood pressure remains elevated, the planned procedure must be postponed until the elevated blood pressure has been lowered to a more acceptable range.

Adapted from Malamed SF: Medical emergencies in the dental office, ed 6, St Louis, 2007, Mosby.

Blood Pressure Equipment and Measurement

Sphygmomanometer (Blood Pressure Cuff)

The sphygmomanometer consists of a pressure-measuring device called a manometer and an inflatable cuff that wraps around the arm or leg (Table 11-10). The mercury manometer (Figure 11-9) is an upright tube containing mercury. The column of mercury is moved upward by the pressure created by inflation of the bladder. The height of the mercury column is marked by millimeter calibration. When the cuff is deflated, the mercury must be at zero. Although mercury manometers are more accurate than aneroid manometers, mercury is a health hazard if not properly contained. Local regulations may prohibit the sale or use of mercury-containing devices.

TABLE 11-10 Main Types of Manometers Used in Blood Pressure Measurement

Name	Advantages	Disadvantages
Mercury sphygmomanometer (see Figure 11-9)	Most accurate	Bulky Possible mercury spillage
Aneroid sphygmomanometer (see Figure 11-9)	Lightweight Portable Compact	Needs to be recalibrated
Electronic sphygmomanometer (see Figure 11-10)	Easy to use Stethoscope not required	Needs to be recalibrated Sensitive to outside interference Susceptible to error

Figure 11-9 Portable sphygmomanometers. Mercury manometer (right). Aneroid manometer (left).

(From Potter PA, Perry AG: Fundamentals of nursing, ed 7, St Louis, 2009, Mosby.)

Portable and lightweight, the aneroid sphygmomanometer (see Figure 11-9) has a glass-enclosed circular gauge containing a needle that registers millimeter calibrations. Aneroid manometers require periodic biomedical calibration to ensure their accuracy. The electronic manometer is easy to use and determines blood pressure automatically (Figure 11-10) without the use of a stethoscope.

Figure 11-10 Automatic blood pressure cuff for home use.

(Courtesy Sedation Resource, Lone Oak, Texas, www.sedationresource.com.)

A baseline blood pressure should be obtained by using the auscultatory method before application of an automatic device because these devices are more susceptible to error. Error is due to the fact that electronic devices are sensitive to outside interference such as client movement or noise. Such factors interfere with the manometer’s sensor signal. An electronic manometer can easily become inaccurate and should be recalibrated more than once a year. An automatic device is not appropriate for clients with certain conditions (Box 11-4).

BOX 11-4 Client Conditions Not Appropriate for Electronic Blood Pressure Measurement

From Potter PA, Perry AG: Fundamentals of nursing, ed 7, St Louis, 2009, Mosby.

• Irregular heart rate

• Peripheral vascular obstruction (e.g., clots, narrowed vessels)

• Shivering

• Seizures

• Excessive tremors

• Inability to cooperate

• Blood pressure less than 90 mm Hg systolic

Parts of a manometer are similar regardless of the type and include an occlusive cloth cuff that encloses an inflatable rubber bladder and a pressure bulb with a release valve that inflates the bladder. Large adult cuffs, thigh cuffs, and pediatric sizes are also available.

Proper cuff size is necessary for accurate blood pressure readings. The cuff size selected is proportional to the circumference of the upper arm being assessed (Figure 11-11). The recommended cuff sizes are as follows⁴:

For arm circumference of 22 to 26 cm, the cuff should be “small adult” size: 12 × 22 cm

For arm circumference of 27 to 34 cm, the cuff should be “adult” size: 16 × 30 cm

For arm circumference of 35 to 44 cm, the cuff should be “large adult” size: 16 × 36 cm

For arm circumference of 45 to 52 cm, the cuff should be “adult thigh” size: 16 × 42 cm

Figure 11-11 Guidelines for proper blood pressure cuff size. Cuff width = 20% more than upper arm diameter or 40% of circumference and two thirds of arm length.

In an adult the bladder within the cuff should encircle at least 80% of the arm, and it should circle the entire arm of a child. Clients with muscular arms that have prominent biceps or obese individuals require use of a large adult cuff. An arm circumference >41 cm requires the use of a thigh cuff (16 × 42 cm).² Blood pressure for morbidly obese individuals with an arm circumference over 52 cm can be measured using an appropriate cuff over the forearm with the stethoscope placed over the radial artery.⁴ Although cuffs may be labeled newborn, infant, child, small adult, and large adult, the practitioner should not rely on client age as the basis for cuff selection. False high readings can occur if the cuff is too narrow; false low readings can occur if the cuff is too wide (Table 11-11).

TABLE 11-11 Common Mistakes in Blood Pressure Assessment

Effect	Error
False high reading	Bladder or cuff too narrow Cuff wrapped too loosely or unevenly Deflating cuff too slowly (false high diastolic reading) Arm below heart level Arm not supported Multiple examiners using different Korotkoff sounds Inflating too slowly or deflating too quickly (false high diastolic) Stethoscope that fits poorly or impairment of examiner’s hearing causing sounds to be muffled (false high systolic) Repeating assessments too quickly (false high systolic)
False low reading	Failure to identify the auscultatory gap Bladder or cuff too wide Deflating cuff too quickly (false low systolic) Arm above heart level Stethoscope that fits poorly or impairment of examiner’s hearing causing sounds to be muffled (false low systolic) Stethoscope pressed too firmly (false low diastolic) Inaccurate inflation level (false low systolic)

Stethoscope

The stethoscope, an instrument used to amplify sound, consists of two earpieces, plastic or rubber tubing, and a chestpiece. The chestpiece has two sides, the bell and the diaphragm (Figure 11-12).

Figure 11-12 Parts of a stethoscope.

(From Potter PA, Perry AG: Fundamentals of nursing, ed 7, St Louis, 2009, Mosby.)

When the bladder within the occluding cuff is deflated, the blood begins to flow intermittently through the brachial artery (Figure 11-13), producing rhythmic, knocking sounds. These sounds are referred to as Korotkoff (ko-rot-kov) sounds. As the cuff is deflated further, the Korotkoff sounds become less audible, and the pulse eventually disappears. See Figure 11-14 for the five Korotkoff sounds described in phases.

Figure 11-13 Location of the brachial and radial arteries. The brachial artery is located on the medial half of the antecubital fossa, whereas the radial artery is on the lateral volar aspect of the wrist.

(From Malamed SF: Medical emergencies in the dental office, ed 6, St Louis, 2007, Mosby.)

Figure 11-14 The sounds auscultated during blood pressure measurement can be differentiated into five Korotkoff phases. In this example, blood pressure is 140/90. Phase 1, The first clear, repetitive tapping sound; recorded as the systolic pressure. Phase 2, Brief period of soft, longer swishing, blowing, and whooshing sounds. Gap, Sound may disappear altogether in some people (auscultatory gap). Phase 3, The return of crisp, sharp, louder thumping sounds. Phase 4, The distinct muffling of the sounds, which become soft and blowing. Phase 5, The point of silence when all sounds disappear because the blood flow returns to normal; recorded as the diastolic pressure.

(From Potter PA, Perry AG: Fundamentals of nursing, ed 7, St Louis, 2009, Mosby.)

An auscultatory gap, a period of abnormal silence that occurs between the Korotkoff phases, is often present in hypertensive clients. This gap usually appears between the first and second systolic sounds. Failure to recognize the auscultatory gap will result in an underestimation of the systolic pressure. Therefore it is important that the dental hygienist assess the point at which the pulse is obliterated while increasing the pressure in the bladder before taking the blood pressure by auscultation. Moreover, the clinician should increase the bladder pressure 30 mm Hg higher than the point at which the pulse is obliterated when measuring blood pressure (Procedure 11-5). Once taken, blood pressure should be documented in writing and dated in the client’s chart under services rendered (e.g., “7/13/09—Blood pressure in right arm, 160/90 mm Hg with auscultatory gap between 160 and 120”).

Procedure 11-5 ASSESSING BLOOD PRESSURE BY AUSCULTATION

Adapted from Potter PA, Perry AG: Fundamental of nursing, ed 7 St Louis, 2009, Mosby.

EQUIPMENT

Blood pressure cuff or sphygmomanometer

Stethoscope

STEPS

1. Ask client about recent activities that could alter the client’s normal blood pressure.

2. Determine proper cuff size. Inspect the parts of the release valve and the pressure bulb. The valve should be clean and freely movable in either direction.

3. Wash hands with antimicrobial soap.

4. Explain purpose of the procedure, but avoid talking to client for at least a minute before taking the client’s blood pressure.

5. Assist client to a comfortable sitting position, with arm slightly flexed, forearm supported, and palm turned up.

6. Expose the upper arm fully.

7. Palpate brachial artery. Position the cuff approximately 1 inch above the brachial artery.

8. Center arrows marked on the cuff over the brachial artery.

9. Be sure cuff is fully deflated. Wrap cuff evenly and snugly around the upper arm. Center arrow on cuff over artery. If there is no arrow, estimate center of bladder and place over artery.

10. Be sure manometer is positioned for easy reading.

11. If client’s normal systolic pressure is unknown, palpate the radial artery and rapidly inflate cuff to a pressure 30 mm Hg above the point at which radial pulsation disappears. Deflate the cuff and wait 30 seconds.

12. Place stethoscope earpieces in ears and be sure sounds are clear, not muffled.

13. Place diaphragm (or the bell) of the stethoscope over the brachial artery in the antecubital fossa. The ante-cubital fossa is the depression in the underside of the arm at the bend of the elbow. Avoid contact with blood pressure cuff or clothing.

14. Close valve of pressure bulb clockwise until tight.

15. Inflate cuff to 30 mm Hg above client’s normal systolic level.

16. Slowly release valve, allowing mercury (or needle of the aneroid gauge) to fall at a rate of 2 to 3 mm Hg per second.

17. Note point on manometer at which the first clear sound is heard.

18. Continue cuff deflation, noting point on the manometer at which the sound muffles (phase IV) and disappears (phase V).

19. Deflate cuff rapidly. To determine an average blood pressure and ensure a correct reading, wait 2 minutes, then repeat procedure for the same arm.

20. Remove cuff from client’s arm. Assist client to a comfortable position and cover upper arm.

21. Disinfect earpieces of stethoscope and fold cuff, and store properly in a cool, dry place.

22. Discuss findings with client.

23. Document in ink the completion of this service in client’s record under “Services Rendered.” Record in client’s chart the systolic over the diastolic blood pressure reading in mm Hg, the date, cuff size if it was an atypical size, and arm used for measurement (use guidelines in Tables 11-6 to 11-9 on pp. 187-189 to determine need for a physician referral). For example: “12/1/09 Client’s blood pressure measured with adult size cuff is 110/75 mm Hg right arm sitting.”

CLIENT EDUCATION TIPS

Educate client when abnormal vital signs are present; initiate proper physician referral when appropriate.

Encourage compliance with recommended physician referrals and prescriptive medications to control abnormal vital signs.

Explain risk factors for abnormal vital signs, e.g., clients with high blood pressure may have no overt symptoms yet be at increased risk for cardiac arrest and stroke.

LEGAL, ETHICAL, AND SAFETY ISSUES

Always record client’s vital signs on the treatment record and refer to client’s baseline readings for comparison. These should be routinely performed at continued care appointments and at each appointment when indicated by the client’s health and pharmacologic history.

Refer client to the physician of record for medical consultation when vital signs exceed normal ranges. Include copies of the referral letter in the client’s chart for access and confirmation.

Disinfect earpiece of stethoscope before and after use to avoid disease transmission.

Never provide dental hygiene care to a client with medical risk greater than an American Society of Anesthesiologists (ASA) III classification.

Vital signs must be measured and recorded during a medical emergency.

Clients in hypertension-prone groups or taking medications that affect blood pressure should have their blood pressure measured at each dental or dental hygiene appointment.

KEY CONCEPTS

Abnormal vital signs can be due to client conditions, equipment failure, or operator error. The dental hygienist must take the vital signs accurately and control factors that contribute to errors.

Blood pressure, pulse, and respiration for baseline measurements should be taken as a comparison for subsequent appointments.

Temperature is not regularly taken; however, the dental hygienist should take the temperature if the client with signs or symptoms of a fever (pyrexia).

Pulse rate is recorded in beats per minute (BPM). The pulse in the radial or carotid artery is often measured using the first two fingers of the clinician’s hand.

Normal pulse rate for an adult at rest can range from 60 to 100 BPM. Children usually have a more rapid pulse rate than adults.

If the client is experiencing five or more premature ventricular contractions (PVCs) per minute, a medical consultation should be considered.

Respiration rate is determined by observing the rise and fall of the client’s chest and is recorded as respirations per minute (RPM).

Normal adult range for respiration rate is 12 to 20 RPM. Children have a more rapid respiratory rate (20 to 30 RPM for a 6-year-old child) than adults.

Two measurements taken for blood pressure are the systolic blood pressure and the diastolic blood pressure.

Optimal systolic and diastolic measurements for adults 18 years of age and older are less than 120/80 mm Hg.

Lifestyle changes are recommended for clients with prehypertension (120 to 139 mm Hg systolic and/or 80 to 89 mm Hg diastolic pressure) with the goal of reducing and/or preventing hypertension.

Treatment is recommended for stages I and II hypertension with the goal of reducing the blood pressure to <140/<90 mm Hg.

Rhythmic, knocking sounds heard via the stethoscope when measuring blood pressure are referred to as Korotkoff sounds.

CRITICAL THINKING EXERCISES

1. The client, a 40-year-old medical resident who works at a hospital emergency room, has a history of missing several dental appointments, numerous cancellations, and rescheduled appointments. She is 10 minutes late for her appointment and on arrival is still dressed in scrubs. On inquiry, she wearily states that she has had about 20 hours of sleep in the last week because of her residency assignment. Her health and pharmacologic history reveals migraine headaches, depression, a prosthetic heart valve, and petit mal and grand mal (tonic-clonic) epileptic seizures. She is currently taking a nonsteroidal antiinflammatory agent for her migraines when needed, a tricyclic antidepressant for depression, and Depakote (an anticonvulsant medication) for her epilepsy. She takes her antidepressant and anticonvulsant on a regular basis and states that she has taken the medications the day of the appointment. She must also take amoxicillin for a prosthetic heart valve and reports an allergy to aspirin products, which has been confirmed by her physician. Her vital signs are pulse 70 BPM, respirations 16 RPM, and blood pressure 120/90 mm Hg.

A. Before initiating dental hygiene care, what should the dental hygienist do?

B. The dental hygienist administers 2% lidocaine with 1:100,000 epinephrine for the PSA injection, giving a total of ¾ of the total cartridge with no complications. Proper local anesthetic technique was given to the client, including aspiration that was negative. The client unexpectedly has a petit mal seizure. What is the most likely cause of the seizure?

C. After the seizure, the client admits that she forgot to take her prophylactic amoxicillin premedication for a prosthetic heart valve. The dental hygienist reschedules the client for treatment, and no treatment other than the local anesthesia administration was given. What recommendation concerning the premedication is indicated before the client is dismissed?

D. The client calls the next day and reports difficulty with mouth opening and soreness of her jaw. What is the most likely cause of the problem?

2. The dental hygienist takes the client’s blood pressure and obtains a reading of 125/90 mm Hg in the right arm. The dental hygienist waits and measures the blood pressure again in 5 minutes, and the blood pressure is 110/70 mm Hg in the right arm. What circumstances could have caused the differences observed in the two readings? Discuss how the problem could be prevented in the future.

3. The dental hygienist takes the client’s pulse several times and measures more than five preventricular contractions per minute. The finding is discussed with the client, and the client is resistant to seeing his or her physician concerning the problem. Role-play with a partner to demonstrate how to effectively manage the situation.

Refer to the Procedures Manual where rationales are provided for the steps outlined in the procedures presented in this chapter.