The Microlife 3AC1: an accurate blood pressure measurement device in pregnancy and pre-eclampsia

A. de Greeff, F. Reggiori, J. Anthony, A. Shennan, 2006

Introduction

As one of the most commonly performed screening tests in pregnancy, accurate blood pressure measurement is vitally important to the diagnosis and management of hypertensive disorders in pregnancy. Few automated devices have been assessed for their accuracy in this population according to a recognized protocol. None of the devices, which achieved sufficient accuracy in pregnancy, were accurate in pre-eclampsia, except for one (device for self-measurement). We assessed the accuracy of the Microlife 3AC1 in a pregnant population, including pre-eclampsia, according to the protocol of British Hypertension Society.

Methods

Forty-five pregnant women were recruited from the antenatal wards and clinics at a large teaching hospital. Sixteen of these women were pre-eclamptic according to the definition of the International Society for the Study of Hypertension in Pregnancy. Nine sequential same arm blood pressure measurements were taken by two trained observers, alternating between a mercury sphygmomanometer and the device. Data was analyzed according to the guidelines of the British Hypertension Society protocol. An A or B grade is required for both systolic and diastolic pressures to pass the protocol.

Results

The Microlife 3AC1 achieved the highest possible grade for accuracy in pregnancy (A/A) and also passed in pre-eclampsia by achieving A/B grade for systolic and diastolic pressure respectively. It also met the standard required by the Association for the Advancement of Medical Instrumentation (AAMI) by achieving a mean difference <5mmHg (SD <8mmHg) for both pregnancy and pre-eclampsia for systolic & diastolic pressures respectively [pregnancy -0.4(5.2) & -1.1(5.9); pre-eclampsia -1.1(7.1) & -3.7(4.1)].

Conclusion

The Microlife 3AC1 can be recommended for use in a pregnant population according to the BHS protocol. It is one of only two devices shown to be accurate in pregnancy, including women with pre-eclampsia.