The measurement of blood pressure and hypertension Handout Fenyvesi Tamás III.Department of Medicine 1
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History of the blood pressure measurement direct Stephen HALES 1726 horse carotid indirect Riva-Rocci Scipione 1896 inflatable bladder Korotkoff 1905 auscultation KopoткoвъНиколайСергеевич 3
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3 The Korotkoff phases I. Appearance of the first tapping sound II. Murmur is heard III. The sounds are crisper and increase in intensity IV. Distinct, definite muffling of the sound V. Disappearance of the sound 5
Technique of measurement systolic bp : the first phase diastolic bp : the fifth phase it used to be a matter of debate the equipment sphygmomanometer rubber bladder and covering cuff ( mercury, aneroid,electronic) width 40-50 % of arm circumference if too narrow overestimates if too wide underestimates length 80% of arm circumference 6
1.quiet environment, 5 minute rest 2. Arm at heart level 3. Manometer at eye level 4. Locate brachial artery by palpation 5. Center the bladder over brachial artery,the lower margin 2,5 cm above antecubital space 6. Inflate the bladder and determine the disappearance of the radial pulse 7. Rapidly deflate 7
8.. Position the stethoscope over the palpated brachial artery 9. Inflate rapidly 30 mmhg above determined level 10. Release the cuff at 2-3 mmhg/s speed 11. Note the systolic BP at the onset of two consecutive beats (Korotkoff I ) 12. Note muffling : Korotkoff IV disappearance : Korotkoff V as diastolic pressure repeat after 2 minutes!! measure by even digits (note the scale!) right down before you forget!!!! 8
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Recording the pressure and the auscultatory gap: range of Korotkoff sounds 10
Determining the palpated systolic pressure and the maximum inflation level 11
Blood pressure cuff placement and pulse detection Figures from: www.images.med 12
The blood pressure cuff and arm circumference 13
Blood pressure cuff sizes, arm circumference ranges, and bladder widths and lengths Blood pressure cuff sizes, arm circumference ranges, and bladder widths and lengths CUFF SIZES ARM CIRCUMFERENCE RANGE AT MIDPOINT, cm BLADDER WIDTH, cm Newborn >6 3 6 Infant 6-15 5 15 Child 16-21 8 21 Small adult 22-26 10 24 Adult 27-34 13 30 Large adult 35-44 16 38 Adult thigh 45-52 20 42 BLADDER LENGTH, cm 14
Calibrating the manometer 15
Measurement of blood pressure in the clinic 16
Interpretation of ABI > 1,30 noncompressible 0,95-1,30 normal 0,41-0,90 mild-to-moderate peripheral arterial disease 0,00-0,40 severe peripheral arterial disease 17
1979 NY 18
Skills a good blood pressure observer must have 19
The measurement is subjective 1. the observer : hand-eye-ear differences 2. the patient : environment, time of the day 3. Interaction : white-coat hypertension" 4. Equipment : calibration, random zero etc 5. ABPM : 24 hours monitoring Special pitfalls: absent phase V, auscultatory gap arrhythmias, obesity Measure on both arms and leg supine and standing 20
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My results mean of 41 measurements Which was the right measurement? No answer!! Such is the method. 22
Special pitfalls absent phase V: aortic insufficiency auscultatory gap arrhythmias, obesity Measure on both arms and one leg supine and standing In outpatients : sitting, on the right arm 23
10 Classification of hypertension by JNCVI (1997) class systolic diastolic optimal <120 <80 normal <130 <85 high normal 130-139 85-89 hypertension 1 stage 140-159 90-99 2 stage 160-179 100-109 3 stage > 180 > 110 This is the presently accepted classification 24
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2003 28
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Blood pressure thresholds (mmhg) for definition of hypertension with different types of measurement SBP DBP Office or clinic 140 90 24-hour 125 130 80 Day 130 135 85 Night 120 70 Home 130 135 85 32
Aetiological classification of hypertension 11 A. Essential hypertension >90% prevalence 10-20% B.Renal hypertension 1. parenchymal: acut glomerulonephritis, chr.nephritis, pyelonephritis 2. renovasular fibromusc., atheroscler 3. trauma: periren haematoma, art.ren thr.,dissection 33
. C.Endocrine 1. thyroid : hyperthyreosis 2. adrenal gland :phaeo,primery hyperaldo, congen hyperplasia, Cushing sy D. Neurogenic: brain tumor, resp acidosis, encephalitis E. Mechanical: coarctation of aorta, AI F. gravidity G. mixed: polycythaemia vera,carcinoid sy burning 34
A hypertension as a risk factor Cardiac hypertrophy, coron disease, infarction Vascular: aortic sclerosis, aneurysm, dissection peripheral arteries, carotid!!! Kidney: decrease of GFR, renal failure Neurological: encephalopathy, stroke!!! Retinal: retinopathy 35
Prevalence of isolated systolic and diastolic blood pressure by age and gender 36
Rate and proportion of cardiovascular disease events by systolic blood pressure level 37
Risk of myocardial infarction with isolated systolic hypertension in men 38
Impact of pulse pressure at specified levels of systolic blood pressure 39
Stroke probability in mildly hypertensive men according to associated risk factors 40
Risk of peripheral arterial disease by systolic blood pressure and diabetic status 41
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A most serious epidemy.unresolved problems Estimated No. of hypertensives in the USA: 41,9 M (RR > 140/90!!) unaware of 31% 13,1 M aware but not treated 17% 7,0 M inefficiently treated 29% 12,0 M well treated 23% 9,7 M 19% of population 65 years, still 45% of all patient who are unaware, are in this age group. ( NEJM 2001;345:479-486) 44
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Association of heart rate with mortality in hypertensive men 46
Cardiovascular disease rates in women according to echocardiogram-left ventricular hypertrophy and hypertensive status 47