VITAL SIGNS Learning objectives After completing this chapter, you will be able to: Explain the physiologic processes responsible for homeostatic regulation for temp, RR, BP and HR Compare factors that increase or decrease the vital signs Identify sites for assessing BP, Temp and HR Accurately assess vital signs Know the normal ranges for vital signs Provide information to patients about taking their vital signs at home Assess the heart sounds Assess the peripheral pulses Vital signs Vital signs are a person’s temperature, pulse, respiration, and blood pressure (abbreviated as T, P, R, BP). Pain is often included as the fifth vital sign. Temperature Pulse Respiration Blood pressure PAIN : 5th vital sign 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 on the body surface • Center initiates responses to produce or conserve body heat or increase heat loss Range of Human Body Temperature Measured Orally HIGH GRADE FEVER>>> (fever of unknown origin, neurogenic) FEVER >>> (infection or tissue injury) AFEBRILE>>> (person drowning >>> in cold water, buried in snow) Heat Production Primary source is metabolism Hormones, muscle movements, and exercise increase metabolism Epinephrine and norepinephrine are released and alter metabolism Thyroid hormones produced by thyroid gland Shivering controlled by the hypothalamus 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 • Evaporation • Conduction Factors affecting body temperature • Circadian rhythms (variations during the 24hrs) • Age and gender • Environmental temperatures (hypothermia, hyperthermia) Physical Effect of Fever Loss of appetite Headaches Hot, dry flushed face Thirst General malaise In children: high grade fevers: SEIZURES, dehydration, decreased urine output and increased HR Nursing interventions (fever treatment) • Monitor temp • Monitor skin status • Monitor BP, HR, and RR • Monitor for decreasing level of consciousness • Monitor for seizures • Monitor lab tests (WBC) • Monitor intake-output, electrolyte imbalance, acid-base status • Administer antipyretics as prescribed • Encourage bathing and increased fluid intake Equipment assessing body temperature • Electronic and digital thermometer • Tympanic membrane thermometer • Glass thermometer • Disposable single-use thermometer • Temporal artery thermometer • Automated monitoring devices Sites & Normal temp for healthy Adults • Oral – 37.0ºC • Rectal – 37.5ºC • Axillary – 36.5ºC • Tympanic – 37.5ºC • Forehead – 34.4ºC Question What is the term for the heat that is lost when a person goes out in the cold without a hat? A. Convection B. Radiation C. Evaporation D. Conduction Respirations • Pulmonary ventilation—movement of air in and out of lungs • Inhalation: breathing in • Exhalation: breathing out • Normal respiration is called eupnea • Under normal conditions, healthy adults breathe about 12 to20 times each minute Factors Affecting Respirations • Exercise • Age & gender • Respiratory and cardiovascular disease • Alterations in fluid, electrolyte, and acid balances • Medications • Trauma • Infection • Pain • Anxiety Assessing respirations • Inspection • Listening with stethoscope • Monitoring arterial blood gas results • Using a pulse oximeter • Pattern: tachypnea, bradypnea, apnea, dyspnea, orthopnea Pulse physiology • Regulated by the autonomic nervous system through cardiac sinoatrial node (SA node) • Parasympathetic stimulation—decreases heart rate • Sympathetic stimulation—increases heart rate • Pulse rate = number of contractions felt over a peripheral artery or heard over the apex of the heart in 1 minute Pulse physiology (cont’d) • stroke volume (SV): quantity of blood forced out of the left ventricle with each contraction • cardiac output(CO): the amount of blood pumped/minute (av: 3.5 L/min to 8.0 L/min • • • • This volume is determined by using the following formula: CO= SV X HR CO (adult) with SV of 70 mL & HR of 70 beats/min= 4.9 L/min. ↑during physical activity &↓ sleep; varies with body size and metabolic needs Question Tell whether the following statement is true or false. The normal pulse rate for adolescents and adults ranges from 60 to 100 beats per minute. A. True B. False Characteristics of the Pulse Increased or decreased pulse rate • Tachy/brady Pulse amplitude and quality • Left ventricular contraction • (0- 4) Regular or irregular pulse rhythm • Arrhythmias/dysrhythmias Assessing Heart Sounds (Refer to your physical assessment book: Weber ch. 11) • Auscultation: determine the heart sounds caused by closure of the heart valves • Focus on the overall rate and rhythm of the heart and the normal heart sounds “lub-dubb” • Systematic auscultation: 1. 2. 3. 4. 5. Aortic area, S2: R 2nd intercostal space (ICS) Pulmonic area, S2: L 2nd ICS Erb’s point: L 3rd ICS Tricuspid area, S1: L 5th (or 4th) ICS Mitral area, S1: 5th L ICS (PMI) • How is 2nd intercostal located ? Locate it by finding the sternal angle (which is felt as a ridge in the sternum approximately 5 cms below the sternal notch). • How is 5th intercostal located ?= is at the junction of the sternum and the xyphoid process Base Precordium Apex S2 S2 L 3rd ICS Erb’s point S1 S1 Sites for Assessing Pulse • Palpating peripheral arteries • Auscultating apical pulse with stethoscope • Assessing apical-radial pulse Sites for Assessing Pulse by Palpation Physiology of Blood Pressure Force of the blood against arterial walls Controlled by a variety of mechanisms to maintain adequate tissue perfusion Pressure rises as ventricle contracts (systole) and falls as heart relaxes (diastole) • Highest pressure is systolic • Lowest pressure is diastolic • Pulse pressure: difference Factors affecting Blood Pressure See box 24-6 page 532 • Age, gender, race • Circadian rhythm • Food intake • Exercise • Weight • Emotional state • Body position • Drugs/medications Equipment assessing Blood Pressure • Stethoscope and sphygmomanometer • Cuff size (wide vs. narrow) • Arm position • Doppler ultrasound • Electronic or automated devices Question Which one of the following pulse sites is located on the inside of the elbow? A. Temporal B. Radial C. Femoral D. Brachial Sites for blood Pressure • Brachial • C/I: an arm with IV line, mastectomy • Popliteal • Expected readings: When the patient’s brachial artery is inaccessible, the nurse can assess the blood pressure using the popliteal artery in the leg. The systolic pressure is normally 10 to 40 mm Hg higher at this site, although the diastolic pressure is the same. • Teaching tips: T 24-2 page 539 • Guidelines for Nursing care 24-7 (assessing BP in leg) page 538 Assessing Blood Pressure Listening for Korotkoff sounds with stethoscope • First sound is systolic pressure • Last sound (5th): Change or cessation of sounds occurs—diastolic pressure The brachial artery and popliteal artery are commonly used Blood pressure is measured in millimeters of mercury(mm Hg) and is recorded as a fraction. The numerator is the systolic pressure; the denominator is the diastolic pressure. Parts of a Sphygmomanometer – 3 Sizes of Cuffs Normal Ranges for Vital Signs for Healthy Adults • Oral temperature — 37.0ºC • Pulse rate — 60 to 100 (80 average) b/min • Respirations — 12 to 20 breaths/minute • Blood pressure — 120/80 mmHg
