The present study aimed to determine the amount of fluid medium passing through the Fallopian tubes into the peritoneal cavity during a hysteroscopy. This was done to understand the pathophysiology of complications related to the hysteroscopy. Conducted in a general hospital setting, the study examined the fluid inflow-outflow during a hysteroscopy both in pre- and post-menopausal women. A hysteroscopy was performed vaginoscopically for both diagnostic and therapeutic procedures. The study involved 117 patients. 84 (71.8%) of them were pre-menopausal and 33 (28.2%) were classified as post-menopausal. The fluid volume difference in the peritoneal cavity prior to hysteroscopy was 26.0 ± 4.2 mL in the pre-menopausal and 7.7 ± 2.4 mL (p = .001) in the post-menopausal group. The pre-menopausal group's flow rate through the Fallopian tubes was 1.5 ± 0.2 mL/min. In the post-menopausal group, it was 0.4 ± 0.1 mL/min (p < .05). It was found that during the hysteroscopy in the pre-menopausal patients, more fluid flows through the Fallopian tubes and at a higher flow rate. Impact statement What is already known on this subject? The complications during a hysteroscopy (HSC) are usually fluid-related and can result in adverse events such as a fluid overload, the dissemination of malignant cells, or electrolyte misbalance. Currently, there is a poor understanding of how HSC fluid behaviour impacts on the pathophysiology of these adverse procedure effects. What do the results of this study add? There have been no quantitative studies of the behaviour of fluid inside the uterine cavity during HSC, which means a quantification of fluid inflow and absorption is required. Our study adds a quantitative understanding of fluid behaviour during HSC. It shows increased rates of fluid passage, as well as fluid speed, into the peritoneal cavity in pre-menopausal patients. What are the implications of these findings for clinical practice and/or further research? Due to the higher rates of fluid passage and speed in pre-menstrual patients, caution regarding the complications during hysteroscopy and further studies are needed on the impact of different fluid distribution.
Keywords: Hysteroscopy; distending media complications; peritoneal fluid; transvaginal ultrasonography.