Chapter 24Vital Signs

Vital Signs• Temperature• Pulse• Respiration• Blood pressure

When to Assess Vital Signs• Upon admission to any healthcare agency• Based on agency institutional policy and procedures• Any time there is a change in the patient’s condition• Before and after surgical or invasive diagnostic

procedures• Before and after activity that may increase risk• Before administering medications that affect

cardiovascular or respiratory functioning

Maintenance of Body Temperature• Thermoregulatory center in the hypothalamus regulates

temperature• Center receives messages from cold and warm thermal

receptors in the body• Center initiates responses to produce or conserve body

heat or increase heat loss

Heat Production• Primary source is metabolism• Hormones, muscle movements, and exercise increase

metabolism• Epinephrine and norepinephrine are released and alter

metabolism• Energy production decreases and heat production

increases

Sources of Heat Loss• Skin (primary source)• Evaporation of sweat• Warming and humidifying inspired air • Eliminating urine and feces

Transfer of Body Heat to External Environment• Radiation• Convection ( الحمل (بواسطة• Evaporation• Conduction

Pulse Physiology• Regulated by the autonomic nervous system through

cardiac sinoatrial node• Parasympathetic stimulation — decrease heart rate• Sympathetic stimulation — increases heart rate• Pulse rate = number of contractions over a peripheral

artery in 1 minute

Respirations• Pulmonary ventilation — movement of air in and out of

lungs– Inhalation: breathing in– Exhalation: breathing out

Rate and Depth of Breathing • Changes in response to body demands• Controlled by respiratory centers in the medulla and pons• Activated by impulses from chemoreceptors • Increase in carbon dioxide is the most powerful

respiratory stimulant

Physiology of Blood Pressure• Force of the blood against arterial walls• Controlled by a variety of mechanism to maintain

adequate tissue perfusion• Pressure rises as ventricle contracts and falls as heart

relaxes– Highest pressure is systolic– Lowest pressure is diastolic

Factors Affecting Body Temperature• Circadian rhythms• Age and gender• Environmental temperatures

Pulse Variations• Increased or decreased pulse rate• Pulse amplitude and quality• Regular or irregular pulse rhythm

Factors Affecting Respirations• Exercise • Respiratory and cardiovascular disease • Alterations in fluid, electrolyte, and acid balances• Medications• Trauma• Infection• Pain• Anxiety

Factors Affecting Blood Pressure• Age, gender, race• Circadian rhythm• Food intake• Exercise• Weight• Emotional state• Body position• Drugs/medications

Equipment for Assessing Temperature• Electronic and digital thermometer• Tympanic membrane thermometer• Glass thermometer• Disposable single-use thermometer• Temporal artery thermometer• Automated monitoring devices

Equipment for Assessing Blood Pressure• Stethoscope and sphygmomanometer• Doppler ultrasound• Electronic or automated devices

Sites for Assessing Temperature• Tympanic membrane• Oral• Rectal• Axillary

Sites for Assessing Pulse• Palpating peripheral arteries• Auscultating apical pulse with stethoscope• Assessing apical-radial pulse

Assessing Respirations• Inspection• Listening with stethoscope• Monitoring arterial blood gas results• Using a pulse oximeter

Assessing Blood Pressure• Listening for Korotkoff sounds with stethoscope

– First sound is systolic pressure– Change or cessation of sounds occurs - diastolic

pressure• The brachial artery and popliteal artery are commonly

used

Normal Temperatures for Healthy Adults• Oral – 37.0ºC, 98.6ºF• Rectal – 37.5ºC, 99.5ºF• Axillary – 36.5ºC, 97.6ºF• Tympanic – 37.5ºC, 99.5ºF• Forehead – 34.4ºC, 94.0ºF

Normal ranges for Vital Signs for Healthy Adults• Oral temperature — 37.0ºC, 98.6ºF• Pulse rate — 60 to 100 (80 average)• Respirations — 12 to 20 breaths/minute• Blood pressure — 130/85