Ch 21 vital signs - Fundamental Concepts and skills for nursing textbook PDF

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Fundamental Concepts and skills for nursing textbook...

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Chapter 21: Vital Signs •

Temperature, pulse, respiration, blood pressure, pain level, oxygen saturation level

Overview of Str Structure ucture and Function Related to the Regulation of Vital Signs • •

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Heat is byproduct of metabolism (cellular chemical reactions in the body) Metabolism increased; more heat produced o Causes fever (when pathogens enter body and body tries to destroy) ▪ Pyrogens: cause fever, produced by pathogens that act on thermostat and raise temp Basal Metabolic Rate BMR o Heat produced when body at rest o Average BMR depends on body surface area

What Factors Affect Body Heat Production •

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BMR affected by thyroid hormone o Excessive amounts of thyroid hormone cause inc in metabolic rate o Epinephrine, norepinephrine and testosterone affect metabolic rate Voluntary muscle movement inc BMR and heat production Shivering: involuntary raises heat production up to 5 times

How is Body Temperature Re Regul gul gulated ated • • • • • • • • • • • •

Hypothalamus controls body temperature by feedback mechanism Heat rises above normal; hypothalamus sends signal that causes vasodilation and sweating and inhibiting heat production Drops below normal, vasoconstriction to conserve heat and induce shivering for heat production Heat loss: radiation, conduction, convection, evaporation Blood flow carries heat through skin Surrounding objects warmer: heat radiated to body and absorbed Warm skin touches cool: heat lost by conduction Air causes heat to be transferred from skin to air is convection (fans) Heat loss inc when skin is moistened and evaporation occurs Sweat glands: heat loss Water evaporates, heat transferred to air Heat always being lost from body by evaporation 800 mL from skin and lungs

How Does FFever ever O Occur, ccur, and What are Its Physiologic Effects • • •

Pyrexia (fever) occurs when normal mechanisms of body cannot keep up with excessive heat production and temp rises (over 100.2) Pyrogens like bacteria cause immune response in body and hypo raises body's temp Allow body to become hotter before triggering cooling mechanisms permits body to become more hostile to bacteria and can more effectively destroy them

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Fever stimulates immune system to produce things to fight virus Temp rises above new set point; skin becomes flushed and moist Diaphoresis: excessive sweat production, attempts to cool body by evaporation Metabolic rate rises, greater demand for oxygen and cellular level, fever occurs Heart and resp rates rise to help body meet inc metabolic demand o Oxygen demand cannot be met; cellular hypoxia (insufficient oxygen occurs)

What Physiologic Mechanisms Control the Pulse? •

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Cardiac contractions produce pulse o Blood in aorta causes pressure wave felt over peripheral artery o Cardiac contractions start from SA node ▪ Problems with electrical conduction in hear affects pulse rate o Stroke volume is volume of blood pushed into aorta with each beat ▪ Affects character of the pulse ▪ Weak pulse: fall in stroke volume Amount of blood circulating and degree of vasodilation/constriction Pulse rate times stroke volume = cardiac output o CO = blood pumped by left ventricle in one minute... average 5L per minute

What is Respiration? • • •

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Exchange of oxygen and carbon dioxide in lungs and tissues initiated by breathing Combination of external and internal respiration External: o Ventilation: air in and out of lungs o Dispersion of air throughout the lungs o Diffusion of oxygen and CO2 molecules across alveolar membrane o Perfusion: movement of blood through lungs and tissues Internal: cellular level, oxygen released from hemoglobin and cell release co2 to blood Organs: upper o Three lobes in right long o Bronchial tree carries oxygen o Diaphragm controls inhalation and exhale o Negative pressure in chest during inspiration draws air into lungs o Gas exchange: alveoli o Surfactant secreted by cells in walls of alveoli necessary for alveoli to remain open, reduces surface tension on alveolar wall How is it controlled o Involuntary by pons and medulla of brainstem o Feedback mechanisms o Carotid body receptors in carotid arteries and aortic body signal to alter rate or depth of resp in response to oxygen levels in blood o Increasing co2 and H+ activate receptors

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Messages sent from resp center to muscles controlled by diaphragm and intercostal muscles altering the rate Pumping action of heart brings blood through lung capillaries Co2 carried as bicarbonate ion in blood until it reaches the lungs

What is Blood Pressure? • • •

Pressure exerted on the arterial wall, changes whether heart is pumping or resting Systolic: maximum pressure exerted on artery during left ventricular contraction Diastolic: lower pressure exerted on artery when heart is at rest between contractions

What Physiologic Factors Directly Affect Blood Press Pressure ure • • • • • • • • •

Amount of cardiac output (stroke volume times heart rate) affects blood pressure Blood pressure inc as SV inc CO falls, BP falls Vasoconstriction causes peripheral vascular resistance to rise; pressure within arterial system inc to push blood along Vasodilation: Vas resis drops and pressure dec BV inc (overdydration) BP inc bc of greater volume of blood in same space (vascular system) BV dec bc of bleeding or dehydration, bp dec Blood thicker when excessive blood cells made, bp inc bc more pressure needed to push Vascular walls losen, like during arteriosclerosis (hardening of arteries) and blood aging, bp inc to push blood through more rigid pathways

Aging and Vital Signs •

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Temp less reliable indicator in health bc less likely to develop o Heat loss occurs more often and lead to hypothermia o Older adults often have lower normal temp than avg adult, could be due to lower metabolic rate Heart rate does not change but rhythm may become irregular Resp rate rise slightly as dec in vital capacity occur SBP rises bc aorta dn arteries harden with age Older adults, Diastolic Pressure rises also

Measuring Body Temperature • •

Normal body temp ranges from 97.5-99.5 Some run low normal or high normal temp

Factors Influencing Temperature Readings • •

Rectal probe is usually red Temporal artery: most accurate noninvasive way to measure o Far side o 1 F higher than oral

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o Unaffected by eating, drinking, smoking, mouth breathing Tympanic membrane temp is a good indicator of core body temp ( in deep tissue of body) o Measures heat radiated as Infared energy from tympanic membrane o Unaffected by many things Tymp and temp more expensive Oral: convenient for children and adults o Wait 15-30 minutes before taking if smoking or eating o Do not use glass thermometer orally if patient is uncooperative or at risk for biting on thermometer Rectal used when others cannot, congestion, surgery, seizures, o Do not use for cardiac patients or rectal surgery

Problems of tempera temperature ture re regu gu gulation lation • •

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Hyperthermia: Above 100.2, typically not significant until 101.3; high can cause brain injury 3 stages: onset, febrile, defervescence o Onset: gradually or suddenly o Febrile: temp rises to new set point and remains there until fever resolves ▪ May cause dehydration, convulsions, confusions o Crisis: abrupt decline in fever: body controls infection o Lysis: gradual return to normal temperature o Classified as constant, intermittent, remittent, relapsing Hypothermia: below 95 o Activity of cells reduced, less heat produced, sleepiness o At risk: postoperative patients who have been cooled, infants to cool room temp, chronically ill, homeless o Treatment: warmth, warm fluids, temp to 72 or higher, inc muscle activity, submerge frostbitten areas in warm bath with warm water Know temperature procedures (same as ATI) Nursing Process o Assessment: appropriate sit for temp measurement o Diagnosis: hyper, hypo, ineffective thermoregulation related to neurologic injury o Planning: expected outcomes written, return normal, maintained, o Implementation: check every few hours o Evaluation: see if it was met

Pulse • • • •

Know pulse points Know how to find pulse and apical pulse Pedal pulses: blockage in circulation, put x, use ultrasound doppler Factors affecting pulse o Age: dec o Body: taller slower pulse o Bp: bp inc dec in pulse rate; bp dec, pr inc bc body trying to inc blood pumped

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o Drugs: stimulants vs depressants o Emotions o Blood loss excessive: inc heart rate bc trying to meet tissue oxygen demands o Exercise o Body temp: inc 7-10 beats per degree o Pain: inc Average pulse rates o Normal 60-100 o Athletes: 45-60 o Male: 72 o Female: 76-80 o Child5; 95 o Child 1: 110 o Newborn 120-160 Pulse characteristics o Note rate, rhythm, volume o Begin timing with beat not counted, next is 1 o Arrhythmia: irregular pulse o Know scale o Normal, fast : tachycardia, slow: bradycardia, irregular: arrhythmia o Thready: weak may be irregular o Absent: no pulse

Meas Measurin urin uringg Respirations • • • • • • • • • • • • • • •

Change in respiratory rate may indicate a change in a patients condition but always considered along with other vital signs and assessment data Count for 30 sec times 2, irregular, full minute Factors affecting PR affect RR Resp rate vary with age 1 resp for 4 heart beat Inc levels of co2 or lower levels of 02 in blood cause inc in resp rate to restore balance and expel co2 Head injury inc cranial pressure, dec breathing Lower then 12: restlessness, confusion, cyanosis: bluish Older adult 16-20 Healthy 12-20 Adolescent 16-20 Child 3 20-30 Infant 1 20-40 Newborn 30-80 Respiratory patterns o Eupnea: normal relaxed breathing, insp shorter then exp o Dyspnea: labored breathing, anxiety, flared nostrils

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Tachypnea: inc breathing, fever, diseases, Bradypnea: slow breathing and shallow, when limited air exchanged and less ox taken in ▪ Leads to hypoxemia: dec levels of ox in blood ▪ Recovering from anesthesia or abdominal surgery Hyperventilation ▪ Inc in rate and depth of breaths and co is expelled causing blood level of co to fall ▪ Severe exertion, during high levels of anxiety or fear and with fever Kussmaul resp ▪ Inc rate and depth with panting and exhales • Diabetic acidosis and renal failure Boit resp ▪ 4-5breaths normal and periods of apnea • Occur with intracranial pressure Cheyne stokes ▪ Dyspnea followed by apnea ▪ Resp faster and deeper then slower ▪ Critically ill patients, kidney failure, drug overdose Lung sounds ▪ Crackles: inspiration, sound like hair rubbed between fingers next to ear ▪ Rhonchi: dry rattling sounds due to obstruction ▪ Stertor: soring sound when unable to cough up secretions ▪ Stridor: crowing sound on inspiration caused by obstruction of upper air passages ▪ Wheeze: air forced passed partial obstruction

Measuring Oxygen Saturation of the Blood Measuring Blood Pressure • •

Obtain info about effectiveness of hear contractions and blood volume and obstruction through blood vessels Know patients usual ranges

Korotkoff Sounds • • • • • • • •

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May hear sounds while taking blood pressure Phase 1: tapping: systolic pressure indicated by faint, clear tapping sounds that gradually grow louder Auscultatory gap: no sound: silence as cuff deflates for 30-40 mmHg common with hyper tension Phase II: swishing: murmur or swishing sounds that increase as the cuff is deflated Phase lll: knocking: louder knocking sound that occurs with each heartbeat Phase lV: muffling: sudden change or muffling of the sound (indicates diastolic pressure in children and some adults) Phase V: silence: disappearance of sound marks diastolic pressure in adults Hypertension o Above 140/90 o AA o Older age, obesity, before 45 for men for common, after 65 for women o Prolonged hypertension cause damage to brain kidneys heart o Prehyper: above 120/80 Hypotension o Low pressure below90/60 o Shock: circulatory collapse caused by hemorrhage, vomiting, diarrhea, burns, myocardial infraction o Signs: dec bp, inc pr, cold, dizzy, vision,

Automated Vital Sign Monitors

Documenting Vital Signs • • • •

Small pad and pen Record temperature o Even numbers, place dot on center, intersecting hour and reading, rectal put r Pulse measurements o Each line between bold lines rep 10 pulse beats Record resp o Place dot in center of appropriate line...