UTERINE DOPPLER BLOOD FLOW EVALUATION OF THE EFFECT OF MISOPROSTOL ADMINISTERED PRIOR TO ABDOMINAL MYOMECTOMY: A RANDOMIZED CONTROLLED TRIAL

Abstract

To observe the changes in the vascularity and perfusion of fibroids following administration of sublingual versus rectal misoprostol prior to abdominal myomectomy A randomized, single-blind, clinical trial The study included women with documented uterine fibroids on pelvic imaging scheduled for abdominal myomectomy, aged 18-50 years, pre-operative hemoglobin >8 g/dl, with five or less symptomatic subserous or intramural fibroids and the uterine size less than 24 weeks pregnancy. Sample size was calculated based on a recent study stated that the Resistance index (RI) at 20 min after rectal misoprostol intake was 0.87 ± 0.16. We supposed that sublingual misoprostol will decrease the blood flow to the uterus with increase in RI to 0.97 ± 0.16. Using two sided chi-square test with alpha error of 0.05, a total sample size of at least 82 patients (41 in each arm) had 80% power to detect the difference in mean RI with sublingual misoprostol intake. Women were randomized to (group A) received 400 mcg misoprostol (two tablets) rectally one hour before the operation, and group (B) received 400 mcg misoprostol sublingual at the same time. The fibroid vascularization and that of the surrounding myometrium was visualized using the colour Doppler technique. Blood flow velocity waveforms were obtained by placing the Doppler gate over the maximum colour areas and activating the pulsed Doppler function at that marked site. The vessel was measured after confirming the depth and the angle correction prior to and after insertion. RI and pulsatility index (PI) of the vessel was measured three times (before and 20 min, 40 min after misoprostol intake). The primary outcome was the mean value of intramyometrial blood vessels RI after 20 min misoprostol intake. chi-square test was used to compare the nominal data of the study groups while student t-test was used to compare the quantitative data of the groups. The study enrolled 82 women (41 in each arm). No statistical significant differences between both groups regarding the baseline or clinical data. No statistical differences regarding RI, PI and systolic/diastolic ratio (S/D), at different times of assessment between both groups. RI after 20 min was 0.85 ± 0.11 in the rectal group vs. 0.78 ± 0.11 in the sublingual group (p=0.15). similarly, RI after 40 min was 0.90 ±0.11 in the rectal group vs. 0.85 ± 0.19 in the sublingual group (p=0.07). In both groups there were significant increase in RI, PI and S/D ratio after 20 and 40 min in comparison to the pre-operative data (p<0.01). Misoprostol significantly decrease the vascularity and perfusion of uterine fibroids weather administered rectal or sublingual one hour prior to abdominal myomectomy.