CONTROL OF INTRAUTERINE FLUID PRESSURE DURING OPERATIVE HYSTEROSCOPY

Study Objective. To evaluate the safety of a commonly used piston pump that controls the infusion pressure of low-viscosity fluids in a cont inuous-flow hysteroscopic system during operative hysteroscopy. Design . Consecutive patients requiring operative hysteroscopy. Setting, Thre e hospital facilities in the Midwest. Patients. Sequential sample of 2 50 women who underwent operative hysteroscopy.Interventions. Endometri al ablations, resection of submucosal or pedunculated uterine leiomyom ata with or without endometrial ablation, polyp resections, metroplast y, and lysis of synechiae. Measurements and Main Results. The most ser ious complication of operative hysteroscopy is fluid overload due to i ntravasation into the patient's vascular system. Low-viscosity fluids were infused by the Zimmer Controlled Distention Irrigation System. Th e instrument uses a closed-feedback loop to monitor cavity pressure an d automatically regulates the flow to maintain the set point pressure. It is designed to operate in a pressure range of 0 to 80 mm Hg and at flows in excess of 450 ml/minute. In 250 operative hysteroscopies no fluid complications occurred when intrauterine pressure was maintained below 80 mm Hg. No clinically significant differences in intravasatio n were seen in any type of operative hysteroscopy. Conclusions. This c ontrolled mechanical pump system with exact intrauterine pressure meas urement reduced many technical difficulties associated with low-viscos ity media, and created a safe environment for the media's use in opera tive hysteroscopy.