Intravenous lidocaine infusion as a component of multimodal analgesia for colorectal surgery—measurement of plasma levels

BACKGROUND: Growing evidence suggests that intravenous lidocaine as a component of multimodal analgesia improves recovery after major colorectal surgery. There is little published data regarding ideal dosing and target plasma concentration in this context, and we wanted to establish our dosing schedule was safe by measuring blood levels of lidocaine. METHODS: ) for patients weighing over 70 kg, using actual body weight. RESULTS: in those patients on the lower dose. Mean levels were higher at 6 h than 30 min and higher again at 12 h. There were no adverse events or reports of symptoms of local anaesthetic toxicity. CONCLUSIONS: ; a level above which symptoms of toxicity may be expected. We have changed our dosing protocol to using ideal rather than actual body weight based on these results.