Proper blood pressure measurement technique has important impact on the accuracy of office BP measurement.
Before staring BP measurement, the child should remain sited and relaxed for 3-5 min in a quiet and comfortably warm room. He/she should be sited with back supported, the legs uncrossed, and feet flat against the floor. Supine position is not recommended as may result in higher systolic BP. Common pitfalls including child sitting in the bed with legs hanging and inability to hold without moving or speaking as well as measuring BP in upsent, crying, unable to cooperate children should be avoided.
Blood pressure is usually measured at the right arm. The arm should be supported at heart level. Upper or lower position of the arm results in lower and higher BP, respectively, due to changes in hydrostatic pressure.
Then, appropriate cuff for the arm of the child needs to be selected. A cuff that is too small can overestimate the BP, and a larger cuff may give lower readings. The bladder, that is the inflatable part of the cuff, determines the cuff size. The rule for appropriate cuff size is to measure the arm circumference midway between acromion and olecranon and select a cuff bladder length that would cover 80-100% of the arm circumference. The cuff bladder width should be 40% of the arm circumference. The branchial artery is palpated at the cubital fossa. The midline of the cuff is placed in line with brachial artery 2-3 cm above the cubital fossa. The cuff should fit around the arm but leave room for about 2-3 fingers.
Auscultation using a mercury, hybrid or aneroid sphygmomanometer is considered the gold standard for office BP measurement. However, validated automated (oscillometric) devices using an automated inflating cuff could be used pediatric population. If auscultation is used a high-quality stethoscope is placed over the palpating brachial artery at the cubital fossa. The cuff is inflated 20mmHg above the disappearance of palpating pulse and then is deflated at a rate of 2-3 mmHg per sec. The pressure at which the pulse sound appears is the Korotkoff phase 1 sound representing systolic BP and the pressure at which pulse sounds disappears is Korotkoff phase 4 sound and gives diastolic BP.
According to the European Society of Hypertension 2016 guidelines BP should be measured three times in children and adolescents with an interval of 3 min apart, and then evaluate the average of the last two readings to determine the child’s or adolescent’s BP levels.
All of this leads to the question that the best option for improving the BP-dependent qualification of blood pressure categories is more precise and standardized BP office measurements.
Prof. Stella Stabouli, 1st Department of Pediatrics, Aristotle University Thessaloniki, Hippocratio General Hospital
TRANSLATION OF THE ARTICLE
How do we appropriately measure BP GERMAN
How do we appropriately measure BP GREEK
How do we appropriately measure BP LITHUANIAN
How do we appropriately measure BP SPANISH
How do we appropriately measure BP TURKISH