Klyucharov I.V., Prokhorov E.I., Borisov S.L., Kadyrov R.F., Podkurkov A.M., Khasanov A.A. Kazan State Medical University, Ministry of Health of the Russian Federation, Republican Clinical Hospital, Ministry of Health of the Republic of Tatarstan, Eleps Research and Production Company Relevance Maintaining pressure at a minimum level that ensures adequate visibility of the uterine cavity is the primary objective of a hystero pump. On the one hand, precise compliance of actual parameters with the set ones ensures good tolerability of the office hysteroscopy procedure (recommended pressure 40-50 mmHg). On the other hand, maintaining the set parameters during inpatient hysteroresection (pressure from 80 mmHg and above) ensures the safety of the procedure. Material and Methods. We studied the correspondence between the preset pressure values ??and actual ones for two hysteropump models (A, B) in combination with two hysteroscope models (a, b) with sheath external diameters of 3.5 mm and 6 mm and one resectoscope (c) with a sheath external diameter of 9 mm. Both hysteropumps had a roller pump design and were equipped with their own fluid parameter monitoring systems. Tests were conducted in a 95.0 ml cavity, in which a pressure sensor was installed, connected to a computer for recording parameters in digital and graphical form. The fluid flow rate was set at 500 ml per minute. The obtained results were compared with the preset ones. Results of Hysteropump A. For the preset pressure of 50 mmHg, the real pressure in the cavity was 41 (-9), 20 (-30) and 64 (+14) mmHg for hysteroscopes a, b and c, respectively. For the preset pressure of 70 mmHg, the real pressure in the cavity was a = 47 (-23), b = 25 (-45), c = 93 (+23) mmHg. For the preset pressure of 100 mmHg, the real pressure in the cavity was a = 60 (-40), b = 38 (-62), c = 117 (+17) mmHg. For the preset pressure of 140 mmHg, the real pressure in the uterine cavity was a = 62 (-78), b = 50 (-90), c = 120 (-20). Hysteropump B. For the preset pressure of 50 mmHg, the real pressure in the cavity was a = 38 (-12), b = 40 (-10), c = 60 (+10) mmHg. For the preset pressure of 70 mmHg, the real pressure was a = 50 (-20), b = 55 (-15), c = 85 (+15) mmHg. For the preset pressure of 100 mmHg, the real pressure was a = 82 (-18), b = 90 (-10), c = 120 (+20) mmHg. For the preset pressure of 140 mmHg, the real pressure was a = 98 (-42), b = 122 (-18), c = 160 (+20) mmHg. [ /upload/medialibrary/f91/hysteropomp_artikle_small_eleps.gif ] [ /upload/documents/hysteropomp_artikle_big_eleps.gif ] Conclusions: In the two hysteropomp models studied, the actual pressure differs from the preset pressure. This difference ranges from -90 to +32 mmHg, depending on the settings and the algorithm for maintaining the set pressure, as well as the design of the specific hysteroscope. These results substantiate the need to develop a universal algorithm for manual or automatic compensation for the difference between the preset and actual pressure in the uterine cavity.