Re: The effects of aspirin in patients undergoing carpal tunnel decompression

Dear Sir, Anticoagulant agents are routinely prescribed to reduce the risk of thromboembolic complications associated with cerebrovascular, coronary artery and peripheral vascular diseases. Perioperative management of patients on anticoagulants can be challenging. There is a need to balance the risk of haemorrhagic complications of continuing anticoagulant therapy, and the risk of thromboembolic complications of ceasing anticoagulation. Aspirin is one of the most frequently prescribed anticoagulant drugs (doses ranging from 75 to 4325mg). To achieve full reversal, aspirin has to be stopped for at least 5 days. In clinical practice, aspirin is stopped for between 3 days and 2 weeks prior to surgery. There are no studies on intraand postoperative complications of hand surgery in patients who take aspirin perioperatively. To investigate the effects of aspirin in patients undergoing hand surgery, we performed a retrospective study to determine whether patients who continued to take asprin during carpal tunnel decompression (CTD) surgery had an increased incidence of clinically significant complications. All patients who had undergone CTD under the care of the senior author at Pinderfields General Hospital, Plastic Surgery Unit (Wakefield, UK) between 2002 and 2006 were identified and were divided into two groups: aspirin and control (no aspirin). As there was a disparity in numbers in the two groups, we randomly selected an equal number of age-matched patients from the nonanticoagulated group to act as controls. The age of each matched set was within 5 years of each other. All patients had standard open CTD performed under local anaesthetic (plain 1% lignocaine with or without 5mg/ml levobupivocaine) and tourniquet control. Haemostasis was achieved with bipolar diathermy, following the release of the tourniquet. Postoperatively, hand elevation was used in all cases. Of the 140 patients who had undergone CTD, 51 (36%) were on oral anticoagulants for ischaemic heart disease. Two patients on clopidogrel and one on warfarin alone were excluded. No patient in either the aspirin or the control group experienced any bleeding problems or required return to theatre (Table 1). A large prospective study has shown that patients suffering from coronary artery disease who discontinue oral antiplatelet agents (OAA), for example aspirin, are at a 2-fold increased risk of significant and serious thromboemoblic events, including death. Those patients who have an acute coronary event after OAA cessation are at a higher risk of death during the month after the coronary event than non-OAA users (Collet et al., 2004). It has also been reported that aspirin increases the rate of bleeding complications by a factor of 1.5 and that aspirin withdrawal precedes up to 10% of acute cardiovascular syndromes (Burger et al., 2005). Discontinuation of aspirin prior to any surgical procedure can therefore be detrimental to the patients’ health. Our study demonstrates that up to a third of patients undergoing CTD take low-dose aspirin, and that continuation of aspirin (in isolation) did not increase the risk of haemorrhagic or other complications. This study is limited by the number of patients, the low dose of aspirin and the overall low rate of complications following CTD. Table 1—Details of patients in the aspirin and control groups