The Effect of Decreased Uterine Filling Pressure in Hysteroscopy, a Double-blind Control Trial

An a priori sample size calculation was completed. To achieve 80% power and an alpha of .05, the study team needed a sample size of 68 total with 34 participants in each group.The study will be a double-blind randomized control trial. Patients will be recruited based on surgery type (hysteroscopy) and consented using a written consent by the research coordinator with sufficient time to ensure patient comprehension and allow for any questions. The consent process will happen in the pre-operative appointment. Participants will then be randomized to either the standard of care of 80mmHg or the experimental pressure of 60 mmHg for uterine filling pressure via an automated randomization program. The physician performing the surgery and the patient will not know what group they are assigned to. The procedure involved in the study will be hysteroscopy. Hysteroscopy is a procedure that is used to diagnose and sometimes treat intrauterine pathologies. In order to visualize the uterus, pressurized saline is used to distend the uterus.

In this study, the specific hysteroscopic procedure will involve the removal of uterine fibroids with a MyoSure Hysteroscopic Morcellator device. These tissue samples will be collected and sent to Pathology to be weighed. During the surgery, the surgeon will be able to request an adjustment pressure if visualization is not adequate. Physicians will start with a pressure of 80mmHg. Once physician is ready to introduce the myosure hysteroscopy device, the pressure level will then be randomized. During the procedure, monitoring will be done by anesthesia through the use of pulse oximetry and measurement of vitals during the Monitored Anesthesia Care. There is also real-time monitoring of hysteroscopic fluid deficit via the fluid management system that is attached to the hysteroscopic pump. Fluid deficit can also be confirmed by the nurse who manually counts the amount of fluid used during theprocedure. Per policy, once a 2500mL deficit is reached, the procedure is terminated. After the surgery, the surgeon will fill out a questionnaire that measures the outcomes of surgeon satisfaction and visualization during the procedure. The other end points of procedure time, specimen weight, volume of normal saline used, any changes in pressure needed during the surgery, and whether the patient required Lasix post-operatively will also be collected at this time.