Blood pressure measurement


Before starting

·       Introduce yourself to the patient.
·       Confirm his name and date of birth.
·       Explain the procedure and obtain his consent.
·       Tell him that he might feel some discomfort as the cuff is inflated, and that the blood pressure
measurement may have to be repeated.
Avoid white coat hypertension by putting the patient at ease. Briefly discuss a non- threatening subject, such as the patient’s journey to the clinic, or the weather.
The procedure
·       Select an appropriately sized cuff and attach it to the BP machine. This is usually a standard cuff in all but children and the obese.
·       Position the BP machine so that it is roughly at the level of the patient’s heart.
·       Position the measurement column/dial so that it is at eye level (avoids parallax error).
·       Position the patient’s right arm so that it is horizontal at the level of the mid-sternum and free
from obstructive clothing.
·       Locate the brachial artery at about 2 cm above the antecubital fossa.
·       Apply the cuff to the arm, ensuring that the arterial point/arrow is over the brachial artery.
·       Inflate the cuff to 20–30 mmHg higher than the estimated systolic blood pressure. You can es-
timate the systolic blood pressure by palpating the brachial or radial artery pulse and inflating
the cuff until you can no longer feel it.
·       Place the stethoscope over the brachial artery pulse, ensuring that it does not touch the cuff.
·       Reduce the pressure in the cuff at a rate of 2–3 mmHg per second.
·       –  the first consistent Korotkov sounds indicate the systolic blood pressure
·       –  the muffling and disappearance of the Korotkov sounds indicate the diastolic blood pressure
·       Record the blood pressure as the systolic reading over the diastolic reading. Do not attempt
to ‘round off’ your readings; to an examiner’s ear, 144/88 usually rings more true than 140/90.
·       If the blood pressure is higher than 140/90, indicate that you need to take a second reading
after giving the patient a one minute rest.
·       In some situations, it may be appropriate to record the blood pressure in both arms (to inves-
tigate coarctation or dissection of the aorta), and also with the patient lying and standing (to investigate for postural hypotension: a drop in BP on standing of ≥20 mmHg).
After the procedure
·       Ensure that the patient is comfortable.
·       Tell the patient his blood pressure and explain its significance. Hypertension can only be con-
firmed by several blood pressure measurements taken over an extended period of time.
·       Thank the patient.
·       Document the blood pressure recording in the patient’s notes.