Validation of two oscillometric blood pressure devices for use in preeclampsia

Gestational hypertension is on of the most common medical disorder in pregnancy
and occurs in 10-12% of all pregnancies. Accurate measurement of blood pressure
is essential in prenatal care for risk assessment of pregnant women and the
diagnosis of pregnancy induced hypertension and preeclampsia.
The auscultatory technique with a mercury sphygmomanometer is considered the
method of choice, using the first and fifth phases of Korotkoff sounds. [1]
However, there is increasing evidence that this procedure may lead to
misclassification due to patient related, investigator related and device
related factors. Automatic readings may overcome these disadvantages. A number
of automatic devices have been validated in pregnant women. Although the
majority of these devices perform well during normal pregnancy, differences
between automatic reading and auscultatory measurement were large and
unpredictable with most devices in women with preeclampsia.[3-5] Only two
automatic devices (Omron MIT and Microlife 3BTO-A ) have demonstrated
sufficient accuracy for use in women with preeclampsia. [6,7] However, most
women in these studies had only moderately elevated blood pressure and concern
regarding the accuracy at higher blood pressure levels remains. Accuracy at
higher levels in pregnancy is of great importance as medical treatment in
pregnancy is generally considered at higher blood pressure levels than in
non-pregnant individuals. We therefore decided to validate both Microlife
3BTO-A and OMRON in women with moderate to sever preeclampsia

Validation of Microlife 3BTO-A and OMRON for blood pressure measurement in
women with moderate to sever preeclampsia.

The validation procedure will be performed according to the international
protocol for validation of blood pressure devices in adults. [2]. Alternate
auscultatory and automatic readings of systolic and diastolic blood pressure
will be performed. The auscultatory measurements will be performed by two
researchers. The mean value of each pair of investigator measurements will be
calculated. In total, 9 auscultatory and 8 automatic blood pressure readings
will be obtained. The first measurement set of each run is discarded from
analysis.

The repeated blood pressure measurements will give some discomfort to the right
arm of the patient. There is no risk involved for the baby or for the mother*s
health.

References
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animals: part 1: blood pressure measurement in humans: a statement for
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