Quality of Non-invasive Sphygmomanometers in District Health Promoting Hospitals of the 4th Regional Health Promoting Center

Abstract

       Quality of non-invasive sphygmomanometers in district health promoting hospitals of the 4^th regional health promoting center was evaluated. Two thousand and seventy-two machines including 335 of mechanical type and 1,737 of automated type were evaluated during the iscal years of 2013 - 2016. According to the international standard-based Testing Procedures for Medical Measuring Devices TP-MMD-01: Blood Pressure Monitor issued by the Ministry of Public Health of Thailand, the maximum permissible errors (MPE) of the cuf pressure were tested to investigate measurement accuracy of the machines. In addition, air leakage testing rate was measured to investigate integrity of the machine, tube and cuf. For mechanical sphygmomanometers, 21 machines (6.3%) were reported to be failed to meet the MPE criteria due to air bubbles in the tube, possibly contaminated from mercury or leakage of mercury. Sixty-two machines (18.5%) failed to meet the air leakage criteria due to defectiveness of tube, bulb or cuf. Furthermore, 5 machines (1.5%) failed to meet both MPE and air leakage criteria. For automated sphygmomanometers, 28 machines (1.6%) were determined to be failed to meet the MPE criteria because reading values were deviated from reference values of greater than 4 mmHg. Two hundred and forty-two machines (13.9%) failed to meet air leakage criteria because of the defectiveness of air tube or cuf. Moreover, 5 machines (0.5%) failed to meet both MPE and air leakage criteria. Root-cause analysis should be determined after quality of sphygmomanometers was poorly detected. Change or repair of any parts of the machines will result in not only reliability of the machines but also accuracy on diagnosis and monitoring of diseases.