© 2009 The McGraw-Hill Companies, Inc. All rights reserved Vital Signs: Blood Pressure

37-2 © 2009 The McGraw-Hill Companies, Inc. All rights reserved Definition The force at which blood is pumped against the walls of the arteries (mmHg) Two pressure measurements Systolic pressure – measure of pressure when left ventricle contracts Diastolic pressure Measure of pressure when heart relaxes Minimum pressure exerted against the artery walls at all times

37-3 © 2009 The McGraw-Hill Companies, Inc. All rights reserved Diastolic Pressure  Heart at rest  Bottom or second number Systolic Pressure  Contraction of left ventricle  Top or first number A Typical Reading 120/80

37-4 © 2009 The McGraw-Hill Companies, Inc. All rights reserved Equipment to measure BP Sphygmomanometer Inflatable cuff Pressure bulb or other device for inflating cuff Manometer Types of sphygmomanometers Aneroid Electronic Mercury

37-5 © 2009 The McGraw-Hill Companies, Inc. All rights reserved Aneroid sphygmomanometer Circular gauge for registering pressure Each line 2 mmHg Very accurate Must be checked, serviced, and calibrated every 3 to 6 months

37-6 © 2009 The McGraw-Hill Companies, Inc. All rights reserved Electronic Sphygmomanometers Provides a digital readout of the blood pressure Usually includes the pulse rate No stethoscope is needed Easy to use

37-7 © 2009 The McGraw-Hill Companies, Inc. All rights reserved Mercury Sphygmomanometers A column of mercury rises with an increased pressure as the cuff is inflated No longer available for purchase If in use, must be checked, serviced, and calibrated every 6 to 12 months

37-8 © 2009 The McGraw-Hill Companies, Inc. All rights reserved Stethoscope Amplifies body sounds Earpieces Binaurals and tubing Chestpiece Bell – low-pitched sounds Diaphragm – high-pitched sounds Earpieces Binaurals Rubber or plastic tubing Bell Chestpiece Diaphragm

37-9 © 2009 The McGraw-Hill Companies, Inc. All rights reserved Measuring Blood Pressure Place cuff on the upper arm above the brachial pulse site Inflate cuff about 30 mmHg above estimated systolic pressure (palpatory result) or approximately 180 mmHg to 200 mmHg Release the air in cuff and listen for the first heartbeat (systolic pressure) and the last heartbeat (diastolic pressure) Record results with systolic as the top number and diastolic as the bottom number (i.e., 120/76)