AuscultationofHeartSounds andbpmeasurement

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1 EXPERIMENTAL PHYSIOLOGY AuscultationofHeartSounds andbpmeasurement Hui-ping Wang( 王会平 ), PhD Dept. of Physiology, Zhejiang University School of Medicine

2 Objectives To recognize the sounds of the heart To measure the blood pressure at rest To understand how exercise affects blood pressure

3 Exercise 1 Auscultation of Heart Sounds The heart: two separate pumps - a right heart that pumps blood through the lungs - a left heart that pumps blood through the peripheral organs

4 Auscultation of Heart Sounds How the heart works? cardiac ac cycle (two major phases): systole :ventricular contraction and blood ejection diastole: ventricular relaxation and blood filling What happens during cardiac cycle? Pressure Volume Valves Blood flow

5 Heart Sounds The heart sounds are the sounds generated by the beating heart and the resultant flow of blood through it. Normal heart sounds are associated with heart valves closing, causing changes in blood flow. To provide important information about the condition of the heart.

6 Heart Sounds 1 st sound: S1 soft low-pitched lub associated with closure of the AV valves Marks the onset of systole 2 nd sound: S2 louder dup associated with closure of the PA and aortic valves Occurs at the onset of diastole S1 normally occurs just after the QRS complex. S2 normally occurs at the end of the T wave.

7 Stethoscope Most stethoscopes have an endpiece with a flat diaphragm and a concave bell, which is directly connected to the earpieces The bell of the stethoscope is better for detecting lower frequency sounds whilst the diaphragm is better for higher frequencies. earpieces endpiec e The correct use of a stethoscope

8 Sites for auscultation The loudness of heart sounds changes with location. S2 is louder at the base. S1 is louder at the apex The best place to hear the heart valves is not necessarily directly over the anatomical site. Mitral area at the apex beat Tricuspid area inferior right sternal margin Pulmonary area left second intercostal space close to the sternum Aortic area right second intercostal space close to the sternum The location of best auscultation for each heart valve are labeled. l

9 Heart Sounds Heart murmurs A sign of heart disease; provide with a powerful diagnostic clue. Produced by heart defects that cause blood flow to be turbulent. Mitral stenosis -- Accentuated first sound Mitral stenosis -- Presystolic murmur Mitral regurgitation -- systolic murmur Aortic insufficiency -- Loud systolic ejection murmur, third sound

10 Exercise 2 BP measurement Blood pressure is the pressure of the blood flowing through your blood vessels against the vessel walls. Varies in a pulsatile pattern during the cardiac cycle. Arterial Pressure Is assessed by measuring systolic pressure and diastolic pressure systolic pressure (SBP) highest arterial pressure of the cardiac cycle Older patients, SV SBP; dehydration, -blockers, diuretics and blood loss SBP diastolic pressure (DBP) lowest arterial pressure of the cardiac cycle Aortic stiffening DBP Pulse pressure (PP): systolic pressure-diastolic pressure Older patients PP

11 BP measurement Direct method t i l t i f th bl d d df a typical tracing of the blood pressure recorded from an artery using the direct method

12 BP measurement e e Indirect method - Sphygmomanometer (mercury manometer) - Automatic Blood Pressure Monitor

13 Clinical method for measuring arterial pressure See: sphygmomanometry.swf Brachial artery b---systolic BP d or e---diastolic BP

14 Categories for Blood Pressure Levels in Adults (in mmhg) Category Systolic BP (Top number) Diastolic BP (Bottom number) Normal Less than 120 Less than 80 Prehypertension High Blood Pressure Systolic BP Diastolic BP Stage Stage or higher 100 or higher

15 BP measurement e e BEFORE TAKING A MEASUREMENT Avoid eating, smoking, exercising, and bathing for 30 minutes before taking a measurement. Rest for at least 15 minutes before taking the measurement. Stress raises blood pressure. Avoid taking measurements during stressful times. Measurements should be taken in a quiet place. Remove tight-fitting clothing from your arm.

16 BP measurement e e Sit in a chair with your feet flat on the floor. Rest your arm on a table so that the cuff is at the same level as your heart. Remain still and do not talk during the measurement.

17 BP measurement e e Place the blood pressure cuff around the upper portion of the arm of the volunteer. Place the bell or diaphragm of the stethoscope over the brachial artery. Inflate the cuff until the pressure reaches approximately 180 mmhg. Slowly reduce the pressure in the cuff while listening through the stethoscope for Korotkoff sounds. Note the pressure value at which sharp, tapping sounds are first heard. This is the systolic pressure. Continue slowly reducing cuff pressure. The pressure value at the cessation of sound is the diastolic pressure. Record the subject ss blood pressure. Completely deflate the cuff once diastolic pressure is determined.

18 BP measurement e e Warning: - Do not leave the cuff inflated for a a long time (more than 90 seconds or so). - Completely deflate the cuff once diastolic pressure is determined. - Allow the volunteers to flex and extend his or her fingers between the exercises to maintain blood flow.

19 Automatic Blood dpressure Monitor Omron Digital Automatic Blood Pressure Monitor HEM-1000 Upper arm type With full automatic cuff wrapping system

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21 Press the START button. The cuff starts to inflate automatically. Inflation stops and the measurement is started. When the measurement is complete, the arm cuff completely p, p y deflates. Your blood pressure and pulse rate appear on the display.

22 Exercise 3 Blood pressure after exercise Record the volunteer s normal blood pressure at rest The volunteer should exercise (on an exercise bike) for at least 20 mins Begin movement at mph(miles/hour) for 5min 5-7 mph (walking) or mph (running) for 15min Immediately after exercise, the volunteer s blood pressure is measured. Tension control

23 Record the volunteer s blood pressure Resting 10 seconds post-exercise 120 seconds post-exercise Systolic Pressure (mmhg) Diastolic Pressure (mmhg)

24 Questions Explain why ventricular contraction (systole) and the lub sound occur immediately after the QRS complex. Explain why ventricular relaxation (diastole) and the dup sound occur after the T wave. Immediately after exercise, was the blood pressure higher or lower than in the resting period? Why? Changes in the cardiovascular system are only some of a number of changes that occur in the body during and after exercise. What other physical changes did you observe in the volunteer?

25 The End.

26 Thank You.