Measuring Blood Pressure in the Forearm

Measuring Blood Pressure in the Forearm

Equipment
■ Stethoscope.
■ 70% alcohol or benzalkonium chloride wipes.
■ Sphygmomanometer with a cuff of the appropriate size. Assessment
■ Check for factors that can alter the readings (e.g., caffeine, smoking, exercise, stress).
■ In determining which extremity to use, consider factors that affect circulation to the extremity and alter the reading (e.g., avoid an arm with an arteriovenous fistula, a deep vein thrombosis, a graft, schemic changes, an infusing IV, or on the side of a radical mastectomy). Post-Procedure Reassessment
■ Be Smart! When evaluating, check the previous recordings, if any.
■ Because BP changes constantly and because so many factors affect it, you cannot draw conclusions from a single measurement.

Key Points
■ If possible, place the patient in a sitting position, with the feet on the floor and the legs uncrossed.
■ Measure BP after the patient has been inactive for 5 minutes (30 minutes, after strenuous exercise).
■ Support the patient’s arm at the level of the heart.
■ Use a cuff of the appropriate size.
■ Wrap the cuff snugly.
■ Inflate the cuff while palpating the artery. Inflate to 30 mm Hg above the point at which you can no longer feel the artery pulsating.
■ Place the stethoscope on the artery, and release pressure at 2 to 3 mm Hg per second.
■ Record systolic/diastolic pressures (first and last sounds heard— e.g., 110/80 mm Hg).
■ Be Smart! If you must remeasure, wait at least 2 minutes.

Documentation
■ You will usually document BP on a flowsheet. If you chose an alternate site, document the site used and the reason for not using the upper arm.
■ Document the systolic/diastolic readings (e.g., 130/80 mm Hg).
■ If you hear the 4th Korotkoff sound or muffling, document systolic/muffling/diastolic (e.g., 130/80/70 mm Hg).
■ If you hear an auscultatory gap, document, for example “170/90 mm Hg with an auscultatory gap from 170 to 140 mm Hg.”
■ Follow agency policy regarding the recording of muffled sounds.

Wrap cuff snugly. Place about 1 in. (2.5 cm) above antecubital space.

Place the stethoscope over the brachial artery