J.'.~"";i'

Review ofLiterature
though the blood pressure remains within the normal range, and the
woman has appoximately a 60% chance of developing preeclampsia. If
the test is negative, the likelihood of patient developing preeclampsia is
about 1 in 100 (Dekker and Sibai, 1991).
Isometric exercise test: Isometric hand - grip exercise is known to
increase systemic arterial blood pressure, presumably resulting from
increased systemic vascular resistance. Degani et al., (1985) subjected
one hundered healthy primigravid women to an isometric hand - grip
exercise test between 28 and 32 week's gestation. Each woman was
placed in the left lateral position, and blood pressure was recorded at
regular intervals until it remained stable. The patient then was instructed
to press an inflated cuff of a calibrated sphygmomanometer to maximal
voluntary contraction for 30 seconds for a three minute period of
sustained isometric handgrip exercise. The patient then compressed the
inflated sphygmomanometer at a tension level of 50% ofthe subject's
previously determined maximal voluntary contraction. Blood pressure
measurements were taken on the passive ann, and an increase in the
diastolic pressure of 20 mmHg was taken as a positive isometric pressor
response.
The level of mean arterial blood pressure during the second
trimester is a poor predictor of the future development ofeclampsia and
might give the clinician a false sense of security when it is negative « 90
mmHg) (Chesley and Sibai, 1987).
Blood pressure alone is not always a dependable indicator of
severity. For example, an adolescent woman may have 3 + proteinuria
and convulsions while her blood pressure is 140/85 mmHg, whereas most
women with blood pressure as high as 180/120 mmHg do not have
seizures. (Cunningham et al., 1989).
29