ACCURACY OF BLOOD PRESSURE RECORDING BY MANUAL AND AUTOMATED DIGITAL DEVICES: A CLINICAL GUIDELINE

Abstract

Introduction: The Mercury sphygmomanometer, a global
gold standard Blood Pressure (BP) recording device is
being replaced by Automated Wrist, Arm and Finger
devices due to the hazardous effect of mercury on health.
The present study was conducted to test the accuracy of
blood pressure measurements taken with two Automated
blood pressure devices (Arm and Wrist) keeping Mercury
sphygmomanometer as the Gold Standard.
Materials & Methods: A cross sectional comparative
study was done in April 2016 on 120 employees of
Rehman Medical College aged 20-69 years (mean age
34.39 ± 10.49 years), based on convenience sampling and
informed consent; known hypertensive cases and those on
anti-hypertensive medication were excluded on account of
lability of blood pressure recordings. Two readings were
obtained from both arms and wrists by three trained
researchers through calibrated Mercury and Automated
Arm and Wrist devices using standard techniques. Data
were analyzed by SPSS 15.0. Comparisons were done
using T tests and ANOVA, keeping p≤0.05 as significant.
Results: Differences in Systolic Blood Pressures (SBP) of
right and left arms were not significant (p>0.05) for each
device. However significant differences were obtained
(p=0.043) for the right and left upper arm mean Diastolic
Blood Pressures (DBP) by Mercury sphygmomanometer.
The Automated devices differed significantly (p<0.05) from
the Mercury device by reporting higher BP values and
diagnosing many more cases of Systolic and Diastolic
hypertension.
Conclusion: The Mercury device provided more accurate
and consistent BP readings than the automated ones. The
left upper arm should be the preferred location for blood
pressure measurements in clinical practice.