I Gill1, K Gallagher, C A Busch. 1. Trauma and Orthopaedic Department, Ashford & St Peters NHS Trust, Ashford, UK. ian.gill@bsuh.nhs.uk
Abstract
INTRODUCTION: Adequate peri-operative analgesia following total knee arthroplasty (TKA) promotes earlier rehabilitation but remains problematic because of the drug side-effects. Peri-articular multimodal drug infiltration (PMDI) has been developed as an alternative strategy to avoid such complications. Autologous retransfusion drains reduce the need for peri-operative allogenic blood transfusions and the consequent risk. There is a theoretical risk of local anaesthesia toxicity when these systems are used concurrently. We performed a review of current practice to quantify this risk. PATIENTS AND METHODS: A series of 10 patients undergoing TKA by the senior author (CAB) had drain fluid analysed for the concentration of ropivacaine. At the same time, the patients completed a questionnaire to establish the presence of ropivacaine-induced side-effects. RESULTS: The ropivacaine level in the retransfusion blood was less than 10 mg in all patients. This concentration was a factor of 6 below the published safe level. Three patients had minor neurological disturbances which recovered spontaneously and quickly. There were no cases of significant cardiovascular compromise. CONCLUSIONS: The theoretical risk of local anaesthesia toxicity when these systems are used together is negligible and we conclude that peri-articular multimodal drug infiltration is safe in conjunction with the use of autotransfusion drains.
INTRODUCTION: Adequate peri-operative analgesia following total knee arthroplasty (TKA) promotes earlier rehabilitation but remains problematic because of the drug side-effects. Peri-articular multimodal drug infiltration (PMDI) has been developed as an alternative strategy to avoid such complications. Autologous retransfusion drains reduce the need for peri-operative allogenic blood transfusions and the consequent risk. There is a theoretical risk of local anaesthesia toxicity when these systems are used concurrently. We performed a review of current practice to quantify this risk. PATIENTS AND METHODS: A series of 10 patients undergoing TKA by the senior author (CAB) had drain fluid analysed for the concentration of ropivacaine. At the same time, the patients completed a questionnaire to establish the presence of ropivacaine-induced side-effects. RESULTS: The ropivacaine level in the retransfusion blood was less than 10 mg in all patients. This concentration was a factor of 6 below the published safe level. Three patients had minor neurological disturbances which recovered spontaneously and quickly. There were no cases of significant cardiovascular compromise. CONCLUSIONS: The theoretical risk of local anaesthesia toxicity when these systems are used together is negligible and we conclude that peri-articular multimodal drug infiltration is safe in conjunction with the use of autotransfusion drains.
Authors: Constant A Busch; Benjamin J Shore; Rakesh Bhandari; Su Ganapathy; Steven J MacDonald; Robert B Bourne; Cecil H Rorabeck; Richard W McCalden Journal: J Bone Joint Surg Am Date: 2006-05 Impact factor: 5.284