Anaesthetic considerations for hysteroscopic surgery.

Use of the hysteroscope in modern gynaecological practice continues to develop as a diagnostic and management tool for intrauterine disease. Operative hysteroscopy (OH) is now an accepted alternative to hysterectomy for women with menorrhagia. The advantages of OH are associated with its short operating time, rapid post-operative recovery and low morbidity. However, there are concerns about the potential serious complications which can occur during and following OH, and it is important that both surgeons and anaesthetists are aware of these--especially as many procedures take place as day-cases. Much has been written in the urological literature concerning complications of endoscopic surgery. Information gathered from patients with post-transurethral resection of the prostate (TURP) syndrome has been useful in the treatment of gynaecology patients. However, the techniques used in TURP are not entirely comparable to hysteroscopic surgery as the uterus has a very thick wall, which requires higher distension pressures. The main complications of OH are fluid overload, hyponatraemia, hypo-osmolality, haemorrhage, uterine perforation and, rarely, gas or air embolism. Fluid overload with hyponatraemia and hypo-osmolality occurs in up to 6% of cases and it can be fatal. Therefore, all possible measures should be taken to prevent it or to detect it and treat it early. There are no controlled studies comparing different anaesthetic techniques for OH. Regional anaesthesia may offer an advantage over general anaesthesia because it enables early detection of fluid overload. Great care should be taken when positioning the patient to prevent peripheral neuropathy.