If you are a high blood pressure patient, your health care provider may ask you to check your blood pressure at home every day. For an accurate measurement, the blood pressure cuff must fit your arm properly. Miscuffing--using a blood pressure cuff that is too small or too large--is a common error in health care settings as well as at home, according to the American Academy of Family Physicians. The discrepancy in readings is greater when the cuff is too small than if it is too large, according to guidelines developed by the American Heart Association in 2005.
Step 1
Measure your upper arm using a measuring tape. Using your left thumb, hold the end of the tape closest to the 1 inch or 1 cm mark against your right arm at a point about halfway between your armpit and your upper arm. Using the fingers of your left hand, wrap the tape around your arm and note the reading where the long end overlaps the short end. The tape should be snug but not tight.
Step 2
Write down your arm circumference in inches and centimeters. If your tape measure is only marked in inches, multiply that figure by 2.54 to convert to centimeters.
Step 3
Estimate your blood pressure cuff size, based on the recommendations of the Agency for Healthcare Research and Quality: small adult cuff, 22 to 26 cm or approximately 8.6 to 10.2 inches; regular adult cuff, 27 to 34 cm or approximately 10.6 to 13.4 inches; large adult cuff, 35 to 44 cm or approximately 13.8 and 17.3 inches; and adult thigh cuff, 45 to 52 cm or approximately 17.7 and 20.5 inches. AHRQ notes that there are no standard guidelines for blood pressure cuff sizes, so manufacturers' descriptions may vary.
Step 4
Visit a medical supply store, drugstore or pharmacy that sells blood pressure cuffs and monitors. Ask for assistance in locating cuffs within your estimated size range.
Step 5
Try on several cuffs to determine which fits best. The cuff must be placed over bare skin, not over clothing. Locate the brachial artery in your antecubital fossa---inside elbow---by feel or visualization. Holding the cuff in your left hand, wrap it snugly around your right arm, aligning the artery marker---an arrow on the inside of the cuff---with the brachial artery. The lower edge should be about 1 inch above the inside of your elbow, according to the American Academy of Family Physicians.
Step 6
Observe the fit of the cuff on your arm. If you have difficulty fastening the cuff properly, try a different size.
Step 7
Inflate each cuff using the attached inflation button or rubber bulb. If the cuff loosens as you inflate it, let the air out and reposition it on your arm before re-inflating it. If the cuff comes loose again, it is probably too small.
Step 8
Take your selected equipment with you to your next doctor's appointment. After your blood pressure is taken with the office equipment, repeat the measurement using your equipment. If the readings are different, ask the office staff to help you determine the reason for the discrepancy. In addition to improper cuff size, inaccurate readings may be due to technique errors or malfunctioning equipment.
Tips and Warnings
- If you do not have a cloth measuring tape, use a string to measure your upper arm. Wrap it around your arm, then hold the string against a ruler to determine the circumference. Take your blood pressure equipment to your health care provider's office once a year to make sure that it is working properly, according to AAFP. Whenever someone else takes your blood pressure, let him know if you need an unusual size of cuff.
