Postoperative analgesia following knee arthroscopy: an assessment of intra‐articular neostigmine

Abstract

Intra-articular local anaesthetic agents have been shown to reduce postoperative requirements and pain scores following knee arthroscopy [1]. It has been shown that intra-articular administration of the acetylcholinesterase inhibitor neostigmine at a dose of 0.5 mg also has an analgesic effect [2]. In this prospective, randomised, double-blind study we compared the quality and duration of postoperative analgesia provided by intra-articular neostigmine alone and in combination with intra-articular ropivacaine. We compared the analgesic effect of neostigmine when administered peripherally (intra-articularly) and systemically (intramuscularly).Methods One hundred ASA 1-2 patients aged 18-60 years, undergoing unilateral knee arthroscopy, received a standardised anaesthetic. After removal of the arthroscope and wound closure, patients were randomised to one of four groups: A (control): 1 ml saline intramuscularly and 20 ml ropivacacine 0.75% intra-articularly; B: neostigmine 0.5 mg in 1 ml saline intramuscularly and 20 ml ropivacaine 0.75% intra-articularly; C: 1 ml saline intramuscularly and 20 ml ropivacaine 0.75% with neostigmine 0.5 mg in 1 ml saline, intra-articularly; D: 1 ml saline intramuscularly and neostigmine 0.5 mg in 20 ml saline intra-articularly. The tourniquet remained inflated for 5 min following installation of intra-articular drugs. ResultsThe quality of pain, as obtained from VAS scores at intervals up to 4 h after injection, was similar between all groups and the control group A. The only significant difference obtained was between group C and D after 4 h. The time from intra-articular injection to first analgesic request was not significantly improved in any group compared to the control. About half of the patients in groups B and C required extra analgesia compared to the groups A and D, but this was not statistically significant. There was no significant difference between the quality and duration of analgesia provided, or the incidence of side effects, between intramuscular or intra-articular neostigmine.Discussion The use of neostigmine to provide analgesia following knee arthroscopy when used either peripherally or systemically, with or without intra-articular ropivacaine, was found to make no significant difference to the quality and duration of analgesia, when compared to using ropivacaine alone. Neostigmine 0.5 mg was not found to be associated with any significant side effects, regardless of route used. References 1 Lyons B, Lohan D, Flynn CG, Joshi GP, O'Brien TM. Intraarticular analgesia for arthroscopic meniscectomy. British Journal of Anaesthesia 1995; 75: 552-5. 2 Yang LC, Chen LM, Wang CJ, Buerkle H. Postoperative analgesia by intra-articular neostigmine in patients undergoing knee arthroscopy.

No anesthetic or analgesic benefit of neostigmine 1 mg added to intravenous regional anesthesia with lidocaine 0.5% for hand surgery

“…8,9 However, other investigators have shown no benefit of peripherally applied neostigmine. 10,11 A recent study that added neostigmine 500 g or placebo to prilocaine 3 mg/kg in IVRA showed reduction in sensory and motor block onset time and prolongation of time to first analgesic request in the neostigmine group. 12 In this study, we hypothesized that peripheral application of neostigmine 1 mg added to lidocaine for IVRA would prolong postoperative analgesia and reduce analgesic requirement without significant adverse effect.…”