Discharge times for knee arthroscopy in spinal vs. general anesthesia

Abstract

Background. Spinal anesthesia (SPA) and general anesthesia (GA) are both safe techniques for knee arthroscopy. In this prospective, single-centre, randomised, clinical trial we compared the discharge times of SPA using 50mg hyperbaric prilocaine 2% and GA with propofol and sufentanil in patients undergoing ambulatory knee arthroscopy. Methods. 50 patients (18-80 years / American Society of Anaesthesiologists grade I-III) were randomized equally to receive either SPA or GA. The main outcome variable was the time until discharge from the day-surgery centre. Anesthesia related side effects, postoperative analgesics and patient satisfaction were assessed. Results. Two of the spinal blocks failed and GA had to be provided. Despite of a faster recovery (unassisted ambulation: SPA: 90 (90-295)min vs. GA: 156 (93-235)min, p=0.0029), spontaneous voiding led to a delayed discharge in the SPA group (SPA: 240 (135-295)min vs. GA: 156 (93-235)min, p<0.0001). There were no differences between the groups regarding other anesthesia related side effects, postoperative demand of analgesics or patient satisfaction. Conclusion. SPA with 50mg hyperbaric prilocaine 2% leads to a later discharge than GA with sufentanil and propofol. However, a reevaluation of existing discharge recommendations including obligatory micturition is necessary, to make SPA become even more advantageous for ambulatory surgery. © 2014 Versita and Springer-Verlag.