Day-to-Day Care


Observation:  Blood Pressure





Blood pressure (BP) is the force which the blood exerts on the blood vessels in which it is contained.  It is recorded by an instrument called sphygmomanometer and is measured  in millimeters of mercury (mmHg).  Electronic BP set is now commonly used at home.

Blood pressure is measured as "upper" and "lower" pressure.  The upper pressure is called a systolic pressure.  This is the greatest pressure exerted against the blood vessel (arterial wall) during the contraction of the heart.  The lower pressure is called the diastolic pressure.  It is the lowest pressure exerted against the blood vessel (arterial wall) when the heart is in a state of rest.


The normal systolic pressure is less than 130 mmHg, and diastolic pressure, less than 80 mmHg.  This is expressed on paper with the systolic figure over the diastolic in the following way - 120/80 mmHg.  The diastolic pressure is usually about two-thirds of the normal systolic pressure (systolic pressure normally exceeds diastolic pressure by about 40 mmHg).  One has hypertension if his systolic pressure is 140 mmHg or more, or diastolic pressure is 90 mmHg or more, or both.
The level of blood pressure is affected by emotion, posture, age and disease.  It usually drops during sleep and rises when in stress.  Close monitoring of blood pressure is recommended during illness or condition that threatens cardiovascular stability.  Regular measurement is indicated for patients with history of hypertension or hypotension.


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Tips in Measuring Blood Pressure Using an Electronic BP Set


Take blood pressure at approximately the same time daily. Choose a time between meals when the person is calm and relaxed so that the reading stays at its normal level.  Do not take measurement after the person has eaten, ambulated, exercise, or appeared anxious.  If possible, wait until he becomes calm to avoid falsely elevated readings.


To calm the person while taking his blood pressure, take your time and talk to him.


The person has to be either lying or sitting down unless the doctor has specifically asked you to record his blood pressure while he is standing up.


If the person is on antihypertensive medications, measure his blood pressure in a sitting position to ensure accurate measurements.


If the person is not able to achieve a comfortable sitting position due to medical reasons, take the blood pressure in the same position and in the same arm for consistency in readings.


Expose the person's arm above the elbow.  Instruct him to relax his arm.


The person's arm should be extended at heart level and be well supported.  Place the BP set beside his arm and on the same level.  The blood pressure may read falsely high  if the arm is below heart level.


Choose an arm band of appropriate size for the person.  Make sure the cuff (the inflatable elastic bladder) is 20% wider than the circumference of the arm being used for measurement.  An excessively small cuff may cause a falsely high pressure reading; an excessively big one, a falsely low reading.


Apply the deflated arm band firmly around the upper arm, approximately 1 inch above the elbow.  Center the arrow marked on the cuff along the brachial artery.


Alternate arms when performing numerous blood pressure measurements on an elderly to prevent thin and fragile skin from breaking down.


Do not take blood pressure in the arm on the affected side of a mastectomy patient because it may decrease already compromised lymphatic circulation, worsen edema, and damage the arm.


Do not take blood pressure readings in the arm in which there is an intravenous (IV) access device because the access may be compromised.


Do not take blood pressure on the arm with an arteriovenous fistula or a hemodialysis shunt because blood flow through the vascular device may be compromised.


If the reading is abnormal, try not to show any anxiety.  Reassure the person that you are taking his blood pressure in order to monitor his progress.  Check it again in 10 minutes and if it is still abnormal, consult your doctor.


Document the readings, time, positions and the arms used for blood pressure taking.  Correlate the readings with medications, and notify your doctor about abnormal findings or deviations from the baseline status.


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