IntroductionThe absorption of uterine distention fluid during hysteroscopic endometrial resection can cause volumeoverload, which can lead to coagulation dysfunction, acute left heart failure and pulmonary oedema in patients. The effects of spinal anaesthesia and intravenous general anaesthesia on the absorption of normal saline as uterine distention fluid during hysteroscopic surgery remain unclear. The aim of this clinical trial was toobserve the effects of spinal anaesthesia and intravenous general anaesthesia on the absorption of normal saline in patients undergoing hysteroscopic endometrial resection.MethodsA total of 126 patients undergoing elective hysteroscopic endometrial resection were divided into a spinal anaesthesia group (s group) and a propofol-fentanyl intravenous anaesthesia group (PF group), with 63 cases in each group, and both groups were divided into a short-term group (S1group and PF1group) and a long-term group (S2group and PF2group) according to the operation time. The primary outcome was the absorption of normal saline, and the secondary outcomes included the perioperative SBP, DBP, HR and SpO2and postoperative haematocrit values, and the incidence of postoperative complications.ResultsThe volume of saline absorbed was significantly increased in the S2and PF2groups compared with the S1and PF1groups (P< 0.001). There was a significant positive correlation between the amount of normal saline absorbed and the operation time (r= 0.895,P< 0.001). The postoperative haematocrit value was slightly lower than that before the operation in all four groups (P< 0.05), and there were no differences in the incidences of urinary retention, sinus bradycardia or hypotension between groups (P> 0.05).ConclusionsThere was no difference in the effects of spinal anaesthesia and intravenous general anaesthesia on the absorption of normal saline during hysteroscopic endometrial resection, and the absorption of normal saline increased accordingly with the extension of operation time.