BACKGROUND: The aim of this study was to evaluate the effect of vaginal misoprostol for operative hysteroscopy on preoperative gastric contents and the risk of acid aspiration pneumonitis.

METHODS: Sixty-five patients undergoing operative hysteroscopy who received prophylactic vaginal misoprostol 200 µg were assigned to the misoprostol group, and sixty-five gynecologic patients without premedication were assigned to the control group. After preoxygenation, a 14-F multiorifice nasogastric tube was inserted for direct aspiration under target-controlled propofol sedation.

RESULTS: The mean pH value of gastric fluid was significantly higher in the misoprostol group (2.7 ± 1.0) than the control group (1.9 ± 0.7). The mean aspirated volume was (ml) 15.3 ± 7.4 in the misoprostol group and 16.8 ± 6.9 in the control group (P > 0.05). There were significantly less patients at high-risk (gastric fluid volumes > 25 ml and pH < 2.5) in the misoprostol group (8/65, 12.3%) than in the control group (18/65, 27.7%). Prophylactic vaginal misoprostol increases the preoperative gastric pH and reduces the number of at high-risk of acid aspiration pneumonitis.

CONCLUSIONS: Therefore, vaginal misoprostol for outpatient hysteroscopy may have preventive effect on the acid aspiration pneumonitis.