Measurement of blood pressure

 Aim:  Determination of own blood blood pressure.

Requirements: Stethoscope and a mercury sphygmomanometer.

     

                                

Principle: 

The blood flow through a large sized artery is obstructed by means  of air pressure exerted through a rubber bag wrapped around the limb. The pressure is slowly released and the entry of blood through the obstruction is studied by (1) feeling of the pulse(palpatory method), (2) observation of oscillation of the mercury level( oscillatory method) and (3) hearing with the stethoscope the sound  produced in the segment of the artery below the obstruction (auscultatory method). The blood flow stops when the pressure transmitted to the artery through the rubber bag is equal to or more than the blood pressure. The first entry of blood through an obstruction indicates the blood pressure.

Usually, the arm or thigh is used because there is only one big vessel, which runs superficially in each of these part of the extremities.

Procedure:

1. The subject is asked to sit or lie down at ease on couch in the supine position. The garments round the arms are removed, The arm is placed on the table and the position is adjusted such that it is the level of the heart.
2. The cuff ids tied around the arm. It should be neither too tight to cause any discomfort to the subject, nor too loose to allow its movement round the arm.
3. The artery is felt and its course is marked in the cubital fossa. Also the radial pulse  radial pulse is felt and marked at the place where it is felt best.
4. The manometer is placed by the side of the subject between his arm and the body. The screw of  the rubber pump is tightened and the pump is pressed to inflate the bag. It is inflated to raise the mercury to 200mm level or 2-25mmHg higher after the disappearance of pulse.
5. Keeping the eye fixed at mercury level and the finger at the pulse ( which has disappeared), pressure is slowly released by unscrewing the valve of the rubber pump. The reading of the level of mercury when pulse reappears gives the systolic pressure. This is palpatory method.

Report: The blood pressure of the given subject is ______.