How reliable are the current Blood Pressure Measuring devices in Health Facilities of Bhutan?

Abstract

Background: Accurate blood pressure measurement is vital before any inferences are made on the reading. Since device error is one of the potential causes of inaccurate results, blood pressure measuring (BPM) devices should be periodically assessed for its accuracy. This paper describes the types of BPM devices used in health facilities of Bhutan and the results of their performance verifications.

Method: This study assessed the pressure accuracy and leak rates of BPM devices in use at two regional referral hospitals, district hospitals and BHU I using calibrated Vital Signs Simulator (ProSimTM 8) from Fluke Biomedical as reference device. For pressure accuracy assessment, static pressures were simulated against which simultaneous readings of each of the devices were recorded (n=3). For the leak rate assessment, the simulator was set to a target pressure and leak rate (n=3) were recorded over 1 minute.

Result: A total of 395 devices of three types, viz., 135 aneroid, 125 electronic and 135 mercury were assessed. Deviations in readings of 64.72% of devices were found to be within acceptable range of ± 3 mmHg. The device-type specific pass percentages for pressure accuracy were 6.40 % for electronic, 88.81 % for aneroid and 94.81 % for mercury. A total of 71.85% of devices (aneroid and mercury) had acceptable leak rates of 15 mmHg per minute.

Conclusion: The study shows that not all the blood pressure measuring devices currently being used in the health facilities of Bhutan are accurate. Besides ensuring that only validated BPM devices enter the country, these devices should be verified for its performance periodically once they are in use.