Basic Skill Assessing blood pressure

rationale

A false high reading will result if the arm is below the heart level. A false low reading will result if the arm is above the heart level. Relaxing avoids falsely elevated readings. The brachial artery is exposed when the palm is in the upright position.

step 13

Continue deflating the cuff slowly. The nurse may hear a murmur, a swishing sound, a clear tapping or a muffled sound but the nurse must wait to hear the last sound when determining the diastolic blood pressure reading.

step 12

Deflate the cuff slowly and steadily (2-3 mm Hg/second). Listen for a soft, tapping sound. This is the patient's systolic blood pressure. A rapid deflation results in a false low systolic reading, while a slow deflation results in a false high reading. This sound is known as the first Korotkoff sound.

step 2

Encourage patient to avoid exercise, smoking, and ingestion of caffeine for 15 minutes before assessing blood pressure. Can cause false elevations of blood pressure.

rationale

If a cuff is too wide, a false low reading may occur. If the cuff is too narrow, a false high reading may occur. It is not advisable to use the forearm when a larger cuff is not available as an overestimation of the systolic by 20% can result.

rationale

Murmurs (Korotkoff II), tapping (Korotkoff III), muffled (Korotkoff IV), and end of diastole (Korotkoff V) sound correlates with the beginning and end of diastole. Muffling sounds is best indicator of diastole in children. Korotkoff V sounds may continue all the way to zero in children and athletes.

Normal blood pressure

Newborn 40 Mean (average) Infant to 1 yr S: 65-115 D: 42-80 Age 1-3 S: 95-105 D: 50-65 Age 3-6 S: 95-100 D: 55-60 Age 6-12 S: 100-110 D: 60-70 Age 12-18 S: 110-130 D: 60-80 Adult S: < 120 D: < 80 Pre-hypertensive 120 139 Or 80-89 Stage I hypertension ≥ 140 Or ≥ 90 Stage II hypertension ≥ 160 Or ≥ 90

step 8

Palpate the brachial artery then inflate the cuff until the nurse can no longer feel the pulse. Release the cuff and observe the reading when the nurse can feel the pulse again. This is called the palpable pulse.

step 5

Place the bottom edge of the blood pressure cuff 1 inch above the patient's antecubital area with arrow pointing directly over the brachial artery. Ensures that the blood pressure cuff is in the correct position before inflating cuff.

step 10

Place the diaphragm of the stethoscope lightly over the brachial artery. The bell of the stethoscope may be used if difficulty is encountered hearing low-pitched sounds.

step 3

Place the patient's arm level with the heart, palm up, and in a relaxed, comfortable position. Have the patient relax at least 5 minutes before measurement.

step 7

Position the sphygmomanometer so that the nurse can see the pressure gauge without any problems. The needle of an aneroid gauge should be at zero. If needle is not at zero on an aneroid manometer, the blood pressure reading will be inaccurate. Biomedical calibration should be done every 6 months to ensure accuracy.

step 14

Quickly deflate the cuff completely. Wait 1-2 minutes if the nurse must recheck the blood pressure. Waiting will allow the circulation to return to the hand and prevents decreased circulation to the hand causing discomfort.

step 11

Quickly inflate the cuff by tightening the screw clamp and pumping the cuff up to 30 mm Hg above the palpable pulse. Inflating the cuff quickly will ensure accurate reading; inflating slowly may result in inaccurate reading. The auscultated reading should be slightly higher than the palpable pulse reading.

rationale

Remember this number because when taking the blood pressure the nurse should inflate the cuff to 30mmHg above this number when obtaining the systolic pressure. It ensures that the cuff will be inflated sufficiently to obtain an accurate systolic reading. Overinflating the cuff can be painful and may damage small blood vessels

step 15

Report an abnormal blood pressure to the appropriate personnel along with other pertinent cardiovascular assessment. Any abnormalities in blood pressure readings may indicate cardiac problems which must be addressed immediately. Any abnormal finding must have a corresponding nursing action.

step 1 cuff size

Select a cuff that fits completely around the patient's arm and is about 40% of the circumference of the mid-point of the arm and two-thirds the length of the patient's upper arm. The bladder of the cuff should be approximately 60-80 % of the circumference of the extremity.

step 4

The nurse must be careful in taking the blood pressure in an arm that may be injured when pressure is applied. Blood pressures should not be taken in arms with shunts for hemodialysis, intravenous lines, breast surgery, or traumatic injury. A leg blood pressure can be obtained by using the popliteal artery.

step 9

Wait 30 to 60 seconds to obtain the patient's blood pressure after taking the palpable pulse. A false high reading will be obtained if the blood pressure is auscultated too soon after obtaining the palpable pulse.

step 6

Wrap the cuff snugly allowing space to put the Stethoscope over the brachial artery. Place the cuff directly over the skin not over any type of clothing. A snug fit is required to obtain a correct blood pressure reading. There must be complete and equal compression of the brachial artery.

step 16

note: If the patient is going from a lying to a sitting position, wait at least 2 minutes before taking the blood pressure. Waiting will allow the body's compensatory mechanisms to stabilize the blood pressure.

equipment needed

sphygmomanometer with cuff of correct size stethoscope. Correct cuff size ensures accurate blood pressure.