Chapter 24 Vital 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 (بواسطة الحمل) 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