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Cardiopulmonary Considerations Vital Capacity (VC) VC= max amt. Of air exhaled after complete inspiration VC= TV + IRV + ERV Norms: Elders Males: 3.88l Females 2.61 liters 25 y. o. Males: 5.05l Females 3.35 liters An 65 yo has ~77% of a 25 yo’s VC CP Tests and Measures
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Vital Capacity (VC) • VC= max amt. Of air exhaled after complete inspiration • VC= TV + IRV + ERV • Norms: • Elders Males: 3.88l Females 2.61 liters • 25 y. o. Males: 5.05l Females 3.35 liters • An 65 yo has ~77% of a 25 yo’s VC
CP Tests and Measures • Fick Equation- quantifies ex response • Vo2= Q x a-vo2 where • Q= HR x SV (CO) • CO increases linearly as a function of O2 consumption. Central Component we don’t fix this
T&M con’t • Predicted Max HR = 220-age (+/- 15 bpm) • SV = EDV-ESV • SV > supine secondary to >venous filling and is accompanied by lower HR
A – VO2 • Peripheral component. Can improve this • 1. O2 uptake by skelatal M is reflected by a-vO2 diff • 2. O2 extraction depends on: • O2 content of art bl • Efficiency with which the skelatal m and other tissues extract O2 • Extent of the redistribution of Cardiac Output BL fl
Karvonen Method Target HR • Max HR 220 • Age 70 • 150
Ventilary responses to ExerciseEx of low or mod intensity is ~ to young except that the elder may be ex at a higher % of max capacity.During intense ex. High blood lactate concentrations create > bl acidosis. Increased ventilation occurs to expire CO2 and DEC. acidosisElders work harder breathing during submax ex so the perceive greater exertion
Similarities between the young and old • Exercise requires coordination between all of the systems to achieve gas exchange for work and resting states • Cardiac and resp. systems have inseparable roles in supporting cellular resp in the generation of energy for muscle contraction • Heart disease can cause both abnormal breathing and gas exchange responses • Pulmonary disorders can cause abnormal cardiac responses
Elders response to exercise • O2 consumption is affected secondary to aging of the lungs, heart, and periphery • In general an elder is at a higher percentage of his max exercise, making it appear that elderly perform less external work, to achieve the same heart rate as a younger individual
Max o2 consumption • At 65 years ~ 28.5 ml/kg body wt./min • At 25 years ~ 43ml/kg/min • This decline is secondary to: • Changes in max heart rate • Changes in SV • Changes in A-V O2 diff
Max HR • DEF: highest heart rate attained during max exercise, declines with age • Lower attainable heart rates with age means that an elder has a lower ex capacity and reaches more intense levels then a younger person at lower pulse rates.
Max Stroke Volume • Studies indicate Max SV is lower in the elderly than the young. Max SV is achieved also at a lower O2 consumption • When compared to young people, elders have a 10-20% less SV. This is controversial. Moreover, the level of fitness is asc. With SV at any age.
Factors Affecting SV • 1. End diastolic volume • 2. Myocardial contractility • 3. Perfusion of myocardium 4. Peripheral vascular resistance
Max CO • If Max HR and Max SV decrease then CO decreases. • In truth, in elders, even with dec. max HR, SV can compensate to inc. the CO or maintain the CO during max ex • CO max value occur at a lower level of exercise intensity
Factors that increase the exercise load in the elderly • Increased body weight • Joint stiffness • Loss of tissue compliance
Factors affecting the A-V diff in elderly • Loss of muscle mass • Decreased number of capillaries in muscle • > blood flow to skin
Max O2 consumption • Similar responses are seen with ex training in the young-old to the young. • Max O2 consumption was still lower in the older group • High intensity training results in an increased a-v diff. It is also possible to Increase Max SV
CAD • Most prevalent disease affecting Cardiac functioning in the elderly • Most common cause of death • Asc. With dec. max ex capacity, dec. max O2 consumption, Dec max HR, and dec max SV • Affects contractility and function of the myocardium
Pulmonary function • Significant pulmonary pathology is required to impact on function • PT check ventilary response of elder to exercise, and the effect of exercise training on ventilation
Ventilary responses to Exercise • Ex of low or mod intensity is ~ to young except that the elder may be ex at a higher % of max capacity. • During intense ex. High blood lactate concentrations create > bl acidosis. Increased ventilation occurs to expire CO2 and DEC. acidosis • Elders work harder breathing during submax ex so the perceive greater exertion
Elders with COPD often are SOB with dec. ex intensities, SOB may limit activity more than CV capacity • UE exercise leads to SOB faster than LE because of greater ventilary responses than during LE activity
Effects of exercise training on Ventilary Function • 60-70 yo (young old) aerobic ex programs that last 3 months can change ventilary function
Blood flow distribution: At rest 15-20% of CO muscle, Heart and Brain always have 5%, the rest goes to other tissues esp. viscera • During ex blood is shunted from viscera to exercising m, as much as 85%. This is key to improving VO2
Other terms • MET: 3.5 ml O2/kg/min=1MET • Ejection Fraction: % of EDV pumped from the ventricles. • Ejection Fraction • >.50=N • .40-.50= mild LV dys • .30-.40=mod • <.20-.30 severe • <.20 compromised but not hopeless CHF floppy L vent
Myocardial O2 Consumption (MVO2) • Diastole bl is received via Coronary art • Systole cap and bl fl are compressed by contracting Cardiac m • HR is kept depressed in CAD during ex so bl fl can supply cardiac m • MVO2 is monitored using RPP or Double product • RPP = HR x SBP
Summary of Cardiopulmonary Effect of Aging • Deconditioning secondary to disuse accounts for ½ of the decline occurring between age 30-70; aging causes the other ½ .
Cardiac Diagnosis • Angina. Characterized by s-t segment depression • Dyspnea • CHF
CHF • ~>2million in US. • 10% 50-59 yo. • Def: syndrome with many pathophysiologic and compensatory mechanisms that occur in attempt to maintain adequate ejection of blood from the ventricle each minute CO to the organs and the tissues of the body CI • Most common cause + CMD • Hallmark of CHF is pulmonary edema
CHF • If impairment is secondary to ventricular acceptance of blood it is called Diastolic dysfunction. If it is secondary to ventricular pumping of blood it is referred to as Systolic dysfunction
Common causes of CMD • HTN • CAD (MI, Ischemia) • Arrhythmias • Renal Insuff • Cardiomyopathy • Heart Valve abnormalities • Pericardial effusion • PE SCI Aging
Effects of Aging • During ex elders maintain CO by using Frank-Starling’s principle and Increase EDV which increases SV
Diastolic Dysfunction causes: • Noncompliance of the ventricle may be due to one or all: • Increased relaxation time Cardiac Muscle • Decreased rate ATP hydrolysis and myosin ATPase activity • Ventricular hypertrophy
Training Adaptations form Exercise in the Elderly • Increased joint stability and mobility • Increased neuromuscular coordination • Increased flexibility • Increased endurance and physical work capacity • Modification of coronary risk factors
Symptoms of CHF • Dyspnea • Paroxysmal nocturnal dyspnea • Orthopnea
Signs of CHF • Breathing pattern: Cheyne-Stokes • Rales/Crackles • S3 heart sound which occurs during early systole. Significant of a noncompliant L vent. • Peripheral edema • Pulsus alterans reg rhythm, alt. Strong and weak pulses • Cold/Pale/Cyanotic extremities • Wt. Gain • Sinus tachycardia
Examination • Six minute walk test- measures ex tol, O2 consumption, survival, functional status of pt. with CHF. Submax, put ~max in CHF pt. Also correlates with peak O2 consumption • MLWHFQ • NYHA • Bruce
Response to submax and max ex • Pts. with CHF: • More rapid rise of HR during submax • Lower peak O2 consumption • Flat, blunted and occ. Hypoadaptive systolic BP • Inc. diastolic BP • ECG signs of myocardial ischemia • Easily provoked dyspnea • Lower max work level • Chronotropic and poss inotropic responses • Fatigue and angina
PT mngmt. CHF • 1. Body position • 2. Breathing Ex • Strength can be measured • Diaphragmatic breathing • Inhibition of accessory muscle activity • Pursed lip breathing • Inspiratory muscle training
Guidelines for Exercise training • Decompensated CHF should not start aerobic training until compensated • If a pt. Becomes markedly dyspneic, fatiqued, has an S3 heart sound,or develops rales- modify or terminate session • Ambulation is the most effective and functional mode of ex. Start with short frequent walks and progress to fewer longer bouts. • Measure dyspnea or use the Borg • Intensity should produce mod dyspnea or a Borg of 3/10
Determining Baseline Functional Capacity • 6/12 minute walk test. Record ex response, distance, S&S fatigue, Sweating, leg cramps, SOB • Seated chair step • U of Minn CP Fitness Step Test • Check significant ECG changes if possible
Exercise prescription • Type- Continuous is best, include strengthening, flexibility, relaxation • Intensity- Never exceed 90% of max. General pop 60-80%. Elderly may improve as low as 40% • Use HR, 20-age • Karvonen • % of functional capacity or max MET level • RPE or BORG
EX prescription con’t • Frequency- # session/week • Most studies favor 3-5x/wk to increase VO2 max with no more than 2 days off • 2-3x/wk maintenance • Progression: go on as long as there is good CP tolerance • HR returns to within 6 bpm with in 5 min • Breathing returns to pre ex within 10 min
Documenting CP progress • VO2 increases • Increased MET level • Increased or better tolerance of workload • Decreased heart rate or BP at the same load