American College of Sports Medicine. (2008). Resting and Exercise Blood Pressure and Heart Rate. In: ACSM's health-related physical fitness

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1 American College of Sports Medicine. (2008). Resting and Exercise Blood Pressure and Heart Rate. In: ACSM's health-related physical fitness assessment manual (2nd ed.). New York: Lippincott, Williams and Wilkins.

2 Related Readings Perloff, D., Grim, C., Flack, J., Frohlich, E.D., Hill, M., McDonald, M., & Morgenstern, B.Z. (1993). Human blood pressure determination by sphygmomanometry. Circulation. 88(5 Pt 1), Jones, D.W., Appel, L.J., Sheps, S.G., Roccella, E.J., & Lenfant, C. (2003). Measuring blood pressure accurately: New and persistent challenges. Journal of the American Medical Association. 289(8), [e-reserve]

3 Blood pressure (BP), force against the arteries walls created by the heart as it pumps blood expressed in millimeters of Mercury (mmhg) Systolic blood pressure (SBP), maximum pressure in the arteries when the ventricles contract during a heartbeat SBP thought to represent overall functioning of the left ventricle important indicator of CV function during exercise Diastolic Blood Pressure (DBP), minimum pressure in the arteries when the ventricles relax DBP occurs late in ventricular diastole reflects the peripheral resistance in the arterial vessels to blood flow

4 Hypertension, high BP, resting BP, or both SBP and/or DBP, chronically elevated above desired level normal, pre-hypertensive, Stage 1 hypertension, Stage 2 hypertension Hypotension, low BP symptoms include lightheadedness, dizziness, fainting Heart rate (HR), # of times heart contracts per unit of time expressed as beats per minute (bpm) no standards for exercise HR, but HR response to standard workload important variable and the foundation for CV endurance tests Resting HR (RHR), indicator of CV endurance -tends to lower in aerobically fit individuals used in Karvonen s formula Heart rate reserve (HRR), difference between measured or predicted MHR and RHR

5 Cardiovascular (CV) system transports blood to the body with the heart serving as the pulsatile pump adult heart approx. size of a fist, weighs g four chambers two superior chambers atria two inferior chambers ventricles CV hemodynamics, overall function of CV system (cardiac function) BP and HR, variables responsible for CV hemodynamics combination of BP and HR is known as the rate pressure product (RPP) cardiac output (Q) used to express overall CV hemodynamics Q = stroke volume (SV) x HR SV, volume pumped per beat Calculate Q: HR 70 bpm, SV 70 ml = Q = 4900 ml/minute Circulatory system

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7 Blood Flow Though the Heart

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9 BP measurement integral component of assessment used in risk stratification Importance of BP to health and disease cannot be overemphasized Hypertension termed silent killer people with hypertension often do not recognise condition, typically has no symptoms SBP 140 mm Hg; DBP of 90 mm Hg or on at least two occasions High BP modifiable risk factors for CV disease Nonpharmacological intervention provides effective means to lower BP, useful method for both prevention and treatment of high BP (Burt et al. Arch Intern Med. 153, , 1993) White Coat Syndrome in the measurement of BP Refers to elevation of BP due to effect of being in clinical setting Have client in a relaxed state is important in resting BP measurement

10 Mean systolic and diastolic blood pressures by age and race/ethnicity for men and women, US population 18 years of age and older Burt et al. Hypertension. 25, , Tendency for SBP to rise progressively in both men and women throughout adult life, men had a slightly higher average level of DBP than women

11 NIH Publication No , NIH Classifications of Blood Pressure for Adults Blood Pressure Classification Systolic BP (mm Hg) Diastolic BP (mm Hg) Normal <120 and < 80 Prehypertension or Stage 1 hypertension or Stage 2 hypertension 160 or 100 National High Blood Pressure Education Program. The Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure. National Heart, Lung, and Blood Institute, National Institute of Health, NIH Publication No , Bethesda, MD

12 Algorithm for Treatment of Hypertension Lifestyle Modifications Not at Goal Blood Pressure (<140/90 mmhg) (<130/80 mmhg for those with diabetes or chronic kidney disease) Initial Drug Choices Without Compelling Indications With Compelling Indications Stage 1 Hypertension (SBP or DBP mmhg) Thiazide-type diuretics for most. May consider ACEI, ARB, BB, CCB, or combination. Stage 2 Hypertension (SBP >160 or DBP >100 mmhg) 2-drug combination for most (usually thiazide-type diuretic and ACEI, or ARB, or BB, or CCB) Drug(s) for the compelling indications Other antihypertensive drugs (diuretics, ACEI, ARB, BB, CCB) as needed. Not at Goal Blood Pressure Optimize dosages or add additional drugs until goal blood pressure is achieved. Consider consultation with hypertension specialist. NIH Publication No , 2003.

13 Common method is brachial artery auscultation listening to the sounds of Korotkoff on arterial walls reported accuracy of indirect auscultation is within 10% of direct measures Theory of Auscultation Korotkoff sounds heard through stethoscope during BP measurement come from the turbulence of blood in the artery blood moving from an area of high pressure to area of lower pressure Pressure inside BP cuff occludes brachial artery blood flow pressure in artery equals the pressure inside the BP cuff, first sound = SBP artery is fully opened, Korotkoff sounds disappear, pressure inside cuff = DBP

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15 A. BP, taken with stethoscope B. Sphygmomanometer, inflatable cuff C. Connected by rubber tubes to monometer, measures pressure in millimeters of mercury D. Rubber bulb regulates air during measurements E. BP, force of blood against walls of arteries and veins created by the heart F. BP cuff fits over brachial artery G. Common carotid artery, upper circle H. Radial artery, lower circle for HR

16 Korotkoff Sounds Phase 1. First, initial sound or the onset of sound. Sounds like: clear, repetitive tapping. This sound approximates SBP maximum pressure that occurs near the end of the stroke output or systole of LV SBP reflects the force of contraction of the left ventricle Phase 2. Sounds like: soft tapping or murmur. described as having a swishing component typically 10 to 15 mmhg after onset of sound or below the phase 1 sounds Phase 3. Sounds like: loud tapping sound; high in pitch/intensity sounds are crisper and louder than the phase two sounds Phase 4. Sounds like: muffling, in sound intensity Often considered as true DBP Phase 5. Sounds like: complete disappearance of sound Known as clinical DBP

17 Three major phases of Korotkoff sounds Phase 1 SBP Sharp tapping sound First sound 120 mmhg Phase 4 DBP Phase 5 Clinical DBP Muffling sound Silence 90 mmhg Substantial decrease in sound intensity 80 mmhg Disappearance of sound due to laminar flow non-turbulent

18 Sphygmomanometer: consists of manometer and BP cuff sphygmo- refers to the occlusion of the artery by a cuff manometer is device used to measure pressure Cuff consists of a rubber bladder and two tubes; one to the manometer one to a hand bulb with a valve that is used for inflation Three common BP cuff sizes pediatric cuff for small arm sizes (13 to 20 cm) normal adult cuff arm sizes between (24 and 32 cm) large adult cuff for larger arm sizes (32 to 42 cm)

19 1. Position BP cuff on the upper arm over you client's brachial artery with the cuff at heart level and secure Client's arm should be slightly flexed at elbow 2. Firmly place the bell of stethoscope over the artery in the antecubital fossa 3. Inflate BP cuff up to 150 to 180 mmhg, for a resting BP 4. Deflate the pressure slowly; 2 to 3 mmhg per heartbeat or 2 to 5 mmhg /sec 5. Record measures of SBP and DBP in even numbers 6. Deflate the cuff rapidly to zero after DBP is obtained 7. Wait one full minute before redoing the BP measurement

20 BP response to ex often-used as criterion for test termination SBP marker of left ventricular function during exercise, SBP should rise during aerobic ex (graded or steady-state, constant load ex) DBP remain the same as at rest or slightly decline An abnormal exercise SBP response may predict future resting hypertension individuals with large in SBP during GXT more likely to develop hypertension BP should be taken every 3min during XT tape cuff to the arm with adhesive surgical tape pump cuff up higher than for a resting BP; 180 to 200 mmhg starting point as ex intensity SBP rises, may need to pump cuff up higher; > 220 mmhg may be necessary Abbreviations: XT = exercise testing; GXT = graded exercise test

21 Neiman (2006). Exercise Testing and Prescription - A Health-related approach (6th ed.). New Boston: McGraw Hill. Pattern of SBP and DBP during graded exercise testing During exertion, DPB remains similar to resting DPB reading, whereas SPB rises linearly with the increase in workload

22 Mean arterial pressure (MAP), mean BP in the arterial system MAP represents integration, or combination, of both SBP and DBP Formula for Mean Arterial Pressure MAP = DBP + (0.33 [SBP DBP]) Calculate the following; SBP 150 mmhg and DBP 80 mmhg

23 Blacher et al. Arch Intern Med 160(8), , Pulse pressure (PP), difference between SBP and DBP PP is the change in BP seen during a contraction of the heart PP provides an approximation of SV high PP important risk factor for heart disease Formula for Pulse Pressure PP = SBP DBP Calculate the following; SBP 140 mmhg and DBP 84 mmhg

24 Rate pressure product (RPP), or double product (DP), reflects myocardial (heart) oxygen demand or consumption (mvo 2 ) oxygen demand of heart related to workload of heart RPP is the product of HR and SBP useful in exercise testing and training clients with cardiovascular disease Calculate the following; Formula for Rate Pressure Product RPP = (HR SBP) 10 2 HR 120 bpm and BP 150/90 mmhg during submax XT ACSM HRPFAM. p40, Note: 10 2 = 0.01

25 Heart rate (HR) can be measured by several techniques; Palpation of pulse at an anatomical site Auscultation using a stethoscope Electric HR monitor/watches Electrocardiography Palpation or auscultation; measure number of beats in 15s or 30s, multiply to convert to 1-min value (bpm) 30s count more accurate, less prone to error Calculating target HR (THR) Karvonen formula factors in RHR to calculate THR

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27 Ex HR in clinic best determined by electrocardiography (ECG) Use a heart rate ruler Count the number of large squares between R waves and divide into large blocks between R waves, HR formula 300/2 = 150 bpm Count the number of millimeters between four R waves and divide into 6, mm separate for R waves, HR formula 6000/40 = 150 bpm

28 Normal response to GXT in healthy subjects Fletcher et al. Circulation 104: , 2001.

29 Measurement of HR and BP, both at rest and during exercise, is central in AEP assessment BP skill is especially important to client's overall heart health BP used in risk stratification Blood Pressure Calculations Mean arterial pressure Pulse pressure Rate of pressure product HR measurement and calculation important in ExRx HR measured from the ECG strip several ways Karvonen formula

30 1. What are NIH Classifications of blood pressure for adults? 2. What is White Coat Syndrome? 3. What is cardiac output (Q) used to express? 4. How is Q calculated? 5. Blood pressure calculations MAP, PP, RPP 6. Calculate THR zones at 60% & 80% using Karvonen formula