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Vital Signs
Vital signs (body temperature, pulse rate, respiratory rate,and blood pressure) are four objective
assessment data that indicate how well or poorly the body is functioning. Pain assessment is considered a
fifth vital sign. This subjective assessment is performed at least daily and when-ever vital signs are taken.
VS are very sensitive to alterations in physiology; so midwives measure them at regular intervals(Box 121) or whenever they determine it is appropriate to assess a client’s health status.
I.
Body temperature; refers to the warmth of the human body. Body heat is produced primarily
from exercise and metabolism of food. Heat is lost through the skin, the lungs, and the body’s waste
products through the processes of radiation, conduction, convection, and evaporation (Table 12-1). The
body’s shell temperature(warmth at the skin surface) is usually lower than its core temperature (warmthin
deeper sites within the body like the brain and heart).Core temperature is much more significant than shell
temperature. Temperature Measurement: There are various scales for measuring heat and cold. Some
examples include Kelvin (K), Fahrenheit (F), and centigrade (C) scales. The centigrade temperature scale is
also known as Celsius. Health care professionals commonly use the Fahrenhei tand centigrade scales.
The centigradescale(scale that uses 0°C as the temperature at which water freezes and 100°C as the
point at which it boils) is here. Midwives are required to use both scales occasionally and to convert
between the two measurements (Box 12-2).
Normal Body Temperature: In normal, healthy adults, shell temperature generally ranges from
35.8°to 37.4°C. Core body temperature ranges from 36.4°to 37.3°C.
If a client’s temperature is above or below normal, the midwife records and reports the temperature,
implements nursing and medical interventions for restoring normal body temperature when appropriate,
and reassesses the client frequently.
Temperature Regulation; The anteriorhypothalamus promotes heat loss through vasodilation and
sweating. The posterior hypothalamus promotes two functions: heat conservation and heat production. It
produces heat conservation in the following ways:
1.Adjusting where blood circulates
2.Causing piloerection (the contraction of arrector pilimuscles in skin follicles), which stiffens body
3.Promoting a shivering response.
The hypothalamus promotes heat production by increasing metabolism through secretion of thyroid
hormone as well as epinephrine and norepinephrine from the adrenalmedulla. When functioning
appropriately, the hypothalamus maintains the core temperature set point(optimal body temperature) within
1°C by responding to slight changes in the skin surface and blood temperatures.
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Temperatures above 41°C and below 34°C indicate impairment of the hypothalamic regulatory center;
the chance of survival is diminished when body temperatures exceed 43.3°C or fall below 28.8°C.
Factors Affecting Body Temperature:
Various factors affect body temperature. Examples include food intake, age, climate, gender, exercise
and activity, circadian rhythm, emotions, illness or injury, and medications.
A.
FOOD INTAKE. Food intake, or lack of it, affects thermogenesis(heat production). When a
person consumes food, the body requires energy to digest, absorb, transport, metabolize, and store
nutrients. Protein foods have the greatest thermic effect. Thus, both the amount and type of food eaten
affect body temperature. Dietary restrictions can contribute to decreased body heat as a result of reduced
processing of nutrients.
B.
AGE. Infants and older adults have difficulty maintaining normal body temperature for several
reasons.
Both have limited subcutaneous white adipocytes(fat cells that provide heat insulation and cushioning
of internal structures). The ability of both young and old to shiver and perspire also may be inadequate,
putting them at risk for abnormally low or high body temperatures. Newborns and young infants tend to
experience temperature fluctuations because they have a three times greater surface area from which heat is
lost and a metabolic rate twice that of adults. Older adults also have progressively impaired circulation,
which interferes with losing or retaining heat.
C. CLIMATE. Cool environmental temperatures result in vasoconstriction of surface blood vessels
with subsequent shunting of blood to vital organs. Conversely, those who live in the tropics have a 10% to
20% lower metabolic rate than those in milder climates. Hot climate encourage vasodilation which lead to
heat loss.
D. GENDER. Body temperature increases slightly in women of childbearing age during ovulation.
This probably results from hormonal changes affecting metabolism or tissue injury and repair after release
of an ovum (egg).
E. EXERCISE AND ACTIVITY. Both exercise and activity involve muscle contraction, and increase
body temperature. Shivering is another example of contractile thermogenesis. In contrast, inactivity and
reduced metabolism or nutrient intake may lead to lower body temperature.
F. CIRCADIAN RHYTHM. Circadian rhythms are physiologic changes, such as fluctuations in body
temperature and other vital signs, over 24-hour cycles.
Body temperature fluctuates 0.28°to 1.1°C during a 24-hourperiod. It tends to be lowest from midnight
to dawn and highest in the late afternoon to early evening.
G. EMOTIONS. Emotions affect metabolic rate and the nervous system. People who tend to be
consistently anxious and nervous are likely to have slightly increased body temperatures. Conversely,
people who are apathetic or depressed are prone to have slightly lower body temperatures.
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H. ILLNESS OR INJURY. Diseases, disorders, or injuries that affect the function of the hypothalamus
or mechanisms for heat production and loss alter body temperature, Infection and inflammatory increase
temperature.
I. MEDICATIONS. Various medications affect body temperature by increasing or decreasing
metabolic. Drugs, such as aspirin, acetaminophen ‫أكامول‬, and ibuprofen, ‫ايزوفين‬directly lower body
temperature by acting on the hypothalamus itself. However, they don't lower it if there is no fever.
Assessment Sites Body temperature can be assessed at various locations. The most accurate locations
for measuring core body temperature are the brain, heart, lower third of the esophagus, and urinary bladder.
But, they are not practical.
The most practical and convenient temperature assessment sites are the ear (tympanic membrane),
mouth, rectum, and axilla. These areas are anatomically close to superficial arteries containing warm blood,
enclosed areas where heat loss is minimal, or both
Of the four sites, the ear (more specifically, the tympanic membrane)is the peripheral site that most
closely reflects core body temperature.
Temperature measurements vary slightly depending on the assessment site (Table 12-2).
The midwife documents the assessment site as O for oral, R for rectal, AX for axillary, and T for
tympanic membrane.
1.
The ear: The temperature within the ear near the tympanic membrane has the closest
correlation to core temperature. Tympanic temperature (if taken correctly) are considered more reliable
than those obtained at the oral and axillary sites, but closely to that taken at the rectal.
2.
Temporal artery thermometry: It is so close to the core temperature such as the temperature
within the heart. It is accurate, safe, noninvasive and suitable for all ages.
3.
Oral Site The oral site, or mouth, is convenient. It generally measures 0.8°t 0.5°to 0.6°C
below core temperature. The area under the tongue is in direct proximity to the sublingual artery. Poor
placement or removal of the thermometer before recommended time can result in in accurate
measurements. The oral site is contraindicated for clients who are uncooperative, very young, unconscious,
shivering, prone to seizures, or mouth breathers; those who have had oral surgery; and those who continue
to talk during temperature assessment. To ensure accuracy, the nurse delays oral temperature assessment
for at least 30 minutes after the client has been chewing gum, smoking a cigarette, or eating hot or cold
food or beverages..
4.
Axillary Site Temperature measurements here are generally 0.6°C lower than those obtained
at the oral site and reflect shell rather than core temperature (except in newborns). The axilla is preferred
site for temperature assessment in infants. The axillary site has several advantages for all age groups. It is
readily accessible in most instances, safe, less potential for spreading microorganisms than with the oral
and rectal sites, and it is less disturbing psychologically than the rectal site. But, it requires the longest
assessment time of 5 minutes or longer. Poor circulation, recent bathing, or rubbing the axillary area dry
with a towel also affects the accuracy of the axillary site.
5. Rectal Site A rectal temperature differs only about 0.1°C from core temperature. This area
retains heat longer than other sites. In addition, this site can be embarrassing and emotionally
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traumatic for alert clients. Presence of stool in the rectum, improper placement of the
thermometer, and premature removal affect the accuracy of rectal temperature assessment
Thermometers There are several types of clinical thermometers (instruments used to measure body
temperature): electronic, infrared, chemical, digital, and glass (Table 12-3).
A.
Electronic Thermometers An electronic thermometer uses a temperature-sensitive probe
covered with a disposable sheath and attached by a coiled wire to a display unit. Electronic thermometers
are portable. They are recharged when not in use. Electronic thermometers generally have two types of
probes: one for oral or axillary use and another for rectal use. The electronic unit senses when the
temperature ceases to change and emits a beep. The audible signal alerts the nurse to remove the probe and
read the displayed measurement.
B.
Infrared (Tympanic) Thermometers The device consists of a hand-held covered probe that
is inserted into the ear canal. The probe contains an infrared sensor that detects the warmth radiating from
the tympanic membrane(eardrum) and converts the heat into a temperature measurement in 2 to 5 seconds.
The potential for transferring microorganisms from one client to another is reduced because the probe
cover is changed after each use and because the ear does not contain mucous membrane and its
accompanying secretions. This thermometer can produce inaccurate measurements if:
1.
The ear canal is not straightened appropriately.
2.
The probe is too large for the ear canal ( use of a tympanic thermometer is contraindicated for
children younger than 2 years)
3.
The sensor is directed at the ear canal rather than directly at the tympanic membrane.
4.
There is impacted cerumen (ear wax),
5.
There is fluid behind the tympanic membrane, if there is middle-ear infections.
6.
The drawdown effect(cooling of the ear when it comes in contact with the probe) occurs.
C. Infrared temporal artery thermometer: It uses infrared sensor that compute temperature
measurement.
D.Glass Thermometers Glass thermometers contain mercury and are considered environmentally
toxic.. If a glass thermometer is the only option, the midwife clean it from the bulb of mercury to the
stem before use. After use, she cleans it from the stem to the bulb. See box below
C.
Chemical Thermometers Various chemical thermometers are available. One example is a
paper or plastic strip with chemically treated dots. Chemical dot thermometers are discarded after one use.
D.
Digital Thermometers A plastic digital thermometer looks similar to a glass thermometer and
can be used at oral, axillary, and rectal sites. It has a sensing tip at the end of the stem, an on/off button, and
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a display area that lights up during use. The battery used to operate the thermometer requires occasional
replacement.
Digital thermometers are designed for multiple uses; for this reason, they require
cleaning after use. Digital thermometers are cleaned similarly to glass thermometers except
that they are wiped rather than soaked within alcohol. Disposable
plastic sheaths can be used to cover the probe with each use.
E.
.Automated Monitoring Devices They may measure the temperature, BP, and pulse, as well
as other information such as heart rhythm and oxygen saturation . Most automated monitors are portable
and can be moved from room to room or remain at one client’s bed-side. Their chief advantage is that they
save time and
money. To ensure reliable data, the accuracy of automated devices is compared with data measured
with manual devices on a regular basis.
F.
Continuous Monitoring Devices are used primarily in critical care areas. They measure body
temperature using internal thermistor probes within the esophagus of anesthetized clients, inside the
bladder, or attached to a pulmonary artery catheter. It is usually used for clients with extreme hypothermia
or hyperthermia. Temperature assessment aids in evaluating the effectiveness of these treatment devices.
Elevated Body Temperature A fever (body temperature that exceeds 37.4°C) is a common
indication of illness. Pyrexia is a term used to describe a warmer-than-normal set point. A person with a
fever is said to be febrile (condition in which the temperature is elevated) as opposed to afebrile (no fever).
Common signs and symptoms associated with a fever:
Pinkish, red (flushed) skin that is warm to the touch
Restlessness or, in others, excessive sleepiness
Irritability
Poor appetite
Glassy eyes and sensitivity to light
Increased perspiration
Headache
Tachycardia and tachypnea
Disorientation and confusion (when the temperature is high)
Convulsions in infants and children (when the temperature is high)
Fever blisters around the nose or lips
Hyperthermia(excessively high core temperature) refers to temperature exceeds 40.6°C. At this level,
the person is at extremely high risk for brain damage or death from complications associated with increased
metabolic demands.
Phases of a Fever A fever generally progresses through four distinct phases:
1.Prodromal phase: The client has nonspecific symptoms just before the temperature rises.
2.Onsetor invasion phase: Obvious mechanisms for increasing body temperature, such as shivering,
develop.
3.Stationary phase: The fever is sustained.
4.Resolution phase: Temperature returns to normal (Fig. 12-10).
Nursing Management: As long as a fever remains 38.9°C and the person does not have a chronic
medical condition, fluids or rest may be all that is necessary. Antipyretics(drugs that reduce fever), such as
aspirin, acetaminophen, or ibuprofen, are helpful when a temperature is 38.9°to 40°C. cold compresses are
used for temperatures between 40°to 40.6°C. If the temperature is higher than 40.6°C or if a high
temperature is, more aggressive treatment is warranted.
Nursing Care Plan 12-1describes nursing actions used for a client with a nursing diagnosis of
hyperthermia.
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Subnormal Body Temperature There are several ranges of hypothermia(core body temperature less
than 35°C). A person is considered mildly hypothermic at temperatures of 35°to 34°), moderately
hypothermic at 33.8°to 30°C, and severely hypothermic below 30°C.Cold body temperatures are best
measured with a tympanic thermometer for two reasons. Other clinical thermometers do not have the
capacity to measure temperatures in hypothermic ranges. Also, the blood flow in other sites generally is so
reduced that measurements taken from these sites are inaccurate.
Common signs and symptoms associated with hypothermia:
Shivering until body temperature is extremely low
Pale, cool, and puffy skin
Impaired muscle coordination
Listlessness
Bradycardia and bradypnea
Irregular heart rhythm
Decreased ability to think coherently and use goodjudgment
Diminished ability to feel pain or other sensations
Clients with severe hypothermia usually die. Various supportive measures are implemented when
clients have subnormal body temperatures. See Nursing Guidelines 12-2.
II.
Pulse: a wavelike sensation that can be palpated in a peripheral artery, is produced by the
movement of blood during the heart’s contraction. In most adults, normal value is 60 to 100 times per
minute at rest.
Pulse Rate The pulse rate (number of peripheral pulsations palpated in 1 minute) is counted by
compressing a superficial artery against an underlying bone with the tips of the fingers.
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Rapid Pulse Rate: In adults, it is considered rapid if it exceeds100 beats per minute (bpm) at rest.
Tachycardia(100 to150 bpm) is a fast heart rate, but heart and pulse rates can exceed 150 bpm. Rapid
contraction, if sustained, tends to overwork the heart and may not oxygenate cells.
The term palpitation(awareness of one’s own heart con-traction without having to feel the pulse) can
accompany tachycardia.
Slow Pulse Rate: In adults, it is considered slower than normal if it falls below 60 bpm.
Bradycardia(less than 60 bpm) is less common than tachycardia; it merits prompt reporting and continued
monitoring.
Factors affecting Pulse and Heart Rates:
Any factors that affect the rate of heart contraction also cause comparable effects in pulse rate. Such
factors include:
Age.Some common rates are listed in Table 12-5.
Circadian rhythm. Rates tend to be lower in the morning and increase later in the day.
Gender.Men average approximately 60 to 65 bpm at rest; the average rate for women is
about 7 or 8 bpm faster
Body build;Tall, slender people usually have slower pulsethan short, stout people.
Exercise and activity increase pulse rate and rest decrease the pulse. With regular aerobic
exercise, pulse rate become consistently lower than average.
Stress and emotions such as anger, fear, and excitement increase heart and pulse rates. Pain,
which is stressful can trigger faster rates.
Body temperature. For every degree of centigrade measurement causes a15-bpm increase in
pulse. With a fall in body temperature, an opposite effect occurs.
Blood volume. Excessive blood loss causes the heart and pulse rates to increase.
Drugs. Certain drugs can slow or speed the rate of heart contraction. Caffeine, nicotine,
cocaine, increase heart contractions and subsequently pulse rate.
Pulse Rhythm: (pattern of the pulsations and the pauses between them) is normally regular. That is,
the beats and the pauses occur similarly throughout the time the pulse is palpated.
An arrhythmia or dysrhythmia(irregular pattern of heart-beats) with a consequently irregular pulse
rhythm is reported promptly.
Pulse Volume: (quality of pulsations felt) usually is related to the amount of blood pumped with each
heartbeat, or the force of the heart’s contraction. A normal pulse is described as strong when it can be felt
with mild pressure over the artery. A feeble, weak, or thready pulse describes a pulse that is difficult to feel
or, once felt, is obliterated easily with slight pressure. A rapid, thready pulse is usually a serious sign and
reported promptly. A bounding or full pulse produces a pronounced pulsation that does not easily disappear
with pressure. See (Table 12-6).
Assessment Sites: The arteries used for pulse assessment lie close to the skin. Most, but not all, are
named for the bone over which they are located (Fig. 12-11). These pulse sites are called peripheral pulses
because they are distant from the heart. The radial artery is the site most often used for pulse assessment.
Three alternative assessment techniques can be used instead of or in addition to assessment of a peripheral
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pulse, including: counting the apical heart rate, obtaining an apical–radial rate, and using a Doppler
ultrasounddevice over a peripheral artery.
1.
Apical Heart Rate: (number of ventricular contractions per minute) is considered more
accurate than the radial pulse for two reasons. Counting the apical rate, however, is less convenient than
counting a radial pulse. An apical heart rate generally is assessed when the peripheral pulse is irregular or
difficult to palpate because of a rapid rate or thready quality or when it is necessary to obtain an actual
heart rate. The apical heart rate is counted by listening at the chest with a stethoscope or by feeling the
pulsations in the chest for 1 full minute. When assessing the apical heart rate by listening to the chest, you
listens for the “lub/dub” sound. These two sounds equal one pulsation at a peripheral pulse site.
The apical–radial rate(number of sounds heard at the heart’s apex and the rate of the radial pulse
during the same period) is counted by separate nurses at the same time using one watch or clock. The
apical and radial rates should be the same, but in some clients, they are not. The pulse deficit(difference
between the apical and radial pulse rates) is noted. If a pulse deficit is significant—and the rates have been
counted accurately, the nurse reports the findings promptly and documents them in the client’s medical
record.
2.
Doppler Ultrasound Device: is an electronic instrument that detects the movement of blood
through peripheral blood vessels and converts the movement to a sound. This instrument is helpful when
pulse is very weak to be detected. When the device is used, conductive gel is applied over the arterial site,
and the probe is moved at an angle over the skin until a pulsating sound is heard . The pulsating sounds are
counted, much like the palpated pulsations. The nurse documents the assessment site and use the letter D to
indicate usage of Doppler.
3.
III.
Respiration is the exchange of oxygen and carbon dioxide. When it occurs between the
alveolar and capillary membranes, it is called external respiration. The exchange of oxygen and carbon
dioxide between the blood and body cells is called internal or tissue respiration. Ventilation(movement of
air in and out of the chest) involves inhalation or inspiration (breathing in) and exhalation or
expiration(breathing out).
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Respiratory Rate: (number of ventilations per minute)varies considerably in healthy people, but
normal ranges have been established (Table 12-7). Factors that influence pulse rate generally also affect
respiratory rate. The faster the pulse rate, the faster the respiratory rate, and vice versa. The ratio of one
respiration to approximately four or five heartbeats is fairly consistent in healthy adults.
Rapid Respiratory Rates
Tachypnea(rapid respiratory rate) often accompanies an elevated temperature or diseases that affect
the cardiac and respiratory systems.
Slow Respiratory Rates
Bradypnea(slower-than-normal respiratory rate at rest)can result from medication slows the
respiratory rate, from neurologic disorders or hypothermia.
Breathing Patterns and Abnormal Characteristics
Cheyne-Stokes respiration refers to a breathing pattern in which the depth of respirations gradually
increases, followed by a gradual decrease, and then a period when breathing stops briefly before resuming
again. It is a serious sign that may occur as death approaches.
Hyperventilation(rapid or deep breathing or both) and hypoventilation(diminished breathing) affect
the volume of air entering and leaving the lungs. Changes in ventilation may occur in clients with airway
obstruction or pulmonary or neuromuscular diseases.
Dyspnea(difficult or labored breathing) is almost always accompanied by a rapid respiratory rate as
clients work to improve the efficiency of their breathing. Clients with dyspnea usually appear anxious and
worried. When observing these clients, you should note how much and what type of activity brings on
dyspnea.
Orthopnea(breathing facilitated by sitting up or standing) occurs in clients with dyspnea who find it
easier to breathe this way. The sitting or standing position causes organs in the abdominal cavity to fall
away from the diaphragm with gravity.
Apnea(absence of breathing) is life threatening if it lasts more than 4 to 6 minutes. Prolonged apnea
leads to brain damage or death.
Terms such as stertorous breathing(noisy ventilation)and stridor(harsh, high-pitched sound heard on
inspiration when there is laryngeal obstruction) are used to describe sounds that accompany breathing.
IV. Blood Pressure:
Is the force that the blood exerts within the arteries. Several physiologic variables create BP:
 Circulating blood volume; lower volume decrease BP and excessive blood volume increase
BP.
 Contractility of the heart is influenced by the stretch of the cardiac muscle fibers. The force of
heart contraction is affected by preload. Regular aerobic exercises increase the myocardial
tone.
 Cardiac Output; volume of blood ejected by the Lt ventricle /minute (5-6L). Cardiac out put=
HR x Stroke volume. Cardiac output can be decreased by the regular exercises.
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

Blood viscosity; creates a resistance when the hearts contracts. Blood viscosity increases with
hemo-concentration.
Peripheral resistance; afterload (force against which the heart pumps when ejecting blood).
BP measurement reflects:

The ability of the arteries to stretch

The volume of circulating blood

The amount of resistance the heart must overcome when it pumps blood
Factors affecting BP:
Age; BP tends to rise with age due to arteriosclerosis and atherosclerosis. Hereditary and
life style are risk factors for such conditions.
Circadian rhythm; BP is lowest after midnight and reaches peak during late morning or early
afternoon.
Gender; Females have lower BP than males.
Exercise and activity; BP rises with activity, but regular exercises help keeping BP within
normal.
Emotions and pain; stimulated SNV raises BP.
Miscellaneous factors;
Lying down position reflects BP lower than sitting and standing
BP may be higher with:

Full bladder

Crossed legs

Coldness

Drugs that stimulate hearts such as nicotine and cocaine.
Blood pressure measurement:
Systolic pressure; pressure within the arterial system when the heart contracts
Diastolic pressure; pressure within the arterial system when the heart relaxes and fills with blood.
BP=
systolic pressure(numerator) mmHG
Diastolic pressure (denominator)
Pulse pressure; difference between systolic and diastolic blood pressure. Pulse pressure is considered
normal between 30 and 50, average 40.
Assessment sites:
The major site is over the brachial artery; at the inner aspect of the arm. The radial artery can be
used also. In some cases the popliteal artery is used when;

The client's arm is missed (amputation)

Both of the client's breasts have been removed (mastectomy)

The client has had vascular surgery (AV shunt)

When dressing, or plaster / fiberglass cast obscures the brachial artery.
Equipment for Measuring Blood Pressure : BP most often is measured with a sphygmomanometer
(a device for measuring blood pressure), an inflatable cuff, and a stethoscope. Sphygmomanometer may be
portable or wall mounted. It contains a gauge for measuring the pressure of a gas or liquid. Mercury
manometers have always been considered the gold standard; however, it may be risky because it containing
mercury. Now two types of devices are available for measuring blood pressure noninvasively: the aneroid
and electronic oscillometric manometers.
Mercury sphygmomanometer; the gauge contain mercury. When used the gauge must be on aflat
surface, and the level of the eyes should be equal to the level of mercury.
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ANEROID MANOMETER; measures pressure using a spring mechanism. Its gauge features a
needle that moves around a numbered dial. The numbers correspond to the measurements obtained with a
mercury manometer. Before using an aneroid manometer, the needle on the gauge must be positioned at
zero to ensure an accurate measurement.
Both mercury and aneroid has a bulb to inflate the bladder.
ELECTRONIC OSCILLOMETRIC MANOMETER; it is battery operated or uses power from an
electrical outlet. Unlike an aneroid manometer, it does not require a stethoscope for auscultating sounds
that correspond to pressure measurements. It measures blood pressure with a transducer within the cuff.
The blood pressures reading is visually
Aneroid and electronic monitors have advantages and disadvantages (Table 12-8, p. 206).
Inflatable Cuff; the cuff of a sphygmomanometer contains an inflatable bladder to which two tubes
are attached. One is connected to the manometer, which registers the pressure. The other is attached to a
bulb that is used to inflate the bladder with air. A screw valve on the bulb allows the midwife to fill and
empty the bladder. As the air escapes, the pressure is measured. Cuffs come in various sizes. Note that it is
not the width and length of the cuff itself, but rather the inflatable bladder, that must be the correct size. If
the cuff is too wide, the blood pressure reading will be falsely low. If the cuff is too narrow, the blood
pressure reading will be falsely high. You must select a cuff with an appropriate bladder size for the body
proportions of each client.
Stethoscope A stethoscope(instrument that carries sound to the ears)is composed of eartips, a brace
and binaurals, and tubing leading to a chest piece that may be a bell, diaphragm, or both.
The eartips are generally rubber or plastic. When the stethoscope is used, the eartips are positioned
downward and forward within the ears to produce the best sound perception. If various people are using
stethoscopes, they must clean the eartips with alcohol swaps between uses. Personal stethoscopes also need
periodic cleaning to keep the eartips free of cerumen and dirt.
The best length for good sound conduction is about 50 cm.The bell (cup-shaped chest piece), is used to
detect low-pitched sounds such as those produced in blood vessels. The diaphragm (disk-shaped chest
piece), detects high-pitched sounds such as those in the lungs, heart, or abdomen. A cracked diaphragm
must be replaced.
Measuring Blood Pressure; The first time the BP is measured, it is assessed in each arm. The two
blood pressure measurements should not vary more than 5 to 10 mm Hg unless pathology (disease) is
present. Several variables can result in inaccurate blood pres-sure measurements (Table 12-9).
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Alternative Assessment Techniques; When Korotkoff sounds are difficult to hear in the usual
manner, midwives assess blood pressure using alternative methods. They can measure BP by: palpation or
using a Doppler stethoscope. When BP requires frequent or prolonged assessment, an automated blood
pressure machine is necessary. When the brachial or radial artery is inaccessible in both arms or assessing
BP at these sites is contraindicated, the thigh is an optional alternative.
1. Palpating the Blood Pressure; When palpating the blood pressure, the nurse applies a blood
pressure cuff without using a stethoscope. Just the midwife positions the fingers over the artery
while releasing the cuff pressure. The point at which she feels the first pulsation corresponds to
the systolic pressure. The diastolic pressure cannot be measured. When recording a BP, it is
important to indicate that palpation was used.
2. Doppler Stethoscope; A Doppler stethoscope helps to detect sounds created by the velocity of
blood moving through a blood vessel. The sounds of moving blood cells are reflected toward
the ultrasound receiver, producing a tone. When documenting BP, you write a D to indicate use
of a Doppler.
3. Automatic Blood Pressure Monitoring; An automatic electronic blood pressure monitoring
device consists of a blood pressure cuff attached to a micro-processing unit. When used, the
device records the client’s blood pressure every 10 to 30 minutes or as needed over24 hours.
4. Measuring Thigh Blood Pressure; Midwives use this site for blood pressure assessment when
they cannot obtain readings in either of the client’s arms. The systolic measurement tends to be
10 to 40 mm Hg higher than that obtained in the arms, but the diastolic measurement is similar
High Blood Pressure: Hypertension(high blood pressure) exists when the systolic pressure,
diastolic pressure, or both are sustained above normal levels for the person’s age. For adults 18
years or older, consider a systolic pressure of 140 mm Hg or greater and a diastolic pressure of
90 mm Hg or greater to be abnormally high (Table 12-10).
An occasional elevation in blood pressure does notnecessarily mean a person has hypertension.
It doesmean that the blood pressure should be monitored at various intervals depending on the
significance of themeasurements (Table 12-11).
Monitoring is especially important to determine whether the elevated BP is sustained or the
result of white-coat hypertension(condition in which the blood pressure is elevated when
taken by a health care worker but normal at other times).
Common factors associated with hypertension:
•Anxiety•Obesity•Vascular diseases•Stroke•Heart failure•Kidney diseases.
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Low Blood Pressure; Hypotension(low blood pressure) is when blood pressure measurements
are below the normal systolic values for the person’s age. Having a consistently low
pressure,96/60 mm Hg for example, seems to cause no harm.
Postural Hypotension; a sudden but temporary drop in BP when rising from a reclining position. It is
common with people having circulatory problems. If systole drops more than 20mmHg and diastole drops
more than 10 mmHg, take it in consideration.
Documenting VS:
The midwife should document the VS either in the nurses’ notes or in the demographic sheet.
You need to document:
Temp: value, site, and any other abnormal signs.
Pulse: rate, rhythm, quality, and site if use apical or AR pulse.
Respiration: rate, rhythm, depth, and any abnormal sounds
BP: value, site, and the position.
With all VS; reports the findings of any abnormality promptly and documents them in the client’s
medical record, as well as any abnormal S&Sx associated with it, your actions to manage abnormalities,
and the client’s response.
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