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Cardiac auscultation involves listening to heart sounds using a stethoscope.
The normal heart sounds are S1 and S2 and are heard using the stethoscope's diaphragm.
S3 and S4 are abnormal heart sounds that are low-pitched and are heard using the stethoscope's bell.
Begin cardiac auscultation by positioning the patient either supine or in the left lateral decubitus position.
First, S1 is auscultated at the tricuspid area in the fourth left intercostal space and the mitral area in the fifth intercostal space at the left midclavicular line.
S1 is heard when the mitral and tricuspid valves close.
Next, the S2 sound is auscultated at the aortic area in the second right intercostal space and the pulmonic area in the second left intercostal space.
S2 is heard when the semilunar valves close.
Finally, move to Erb's point in the third left intercostal space to hear equal S1 and S2 sounds.
Use the stethoscope's bell for S3 and S4 sounds. An S3 heart sound indicates heart failure and an S4 heart sound indicates left ventricular hypertrophy and is best heard at the apex.
Cardiac auscultation is a clinical skill used to assess heart function and detect abnormalities. It involves listening to heart sounds at specific ana…
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