Intravenous Lidocaine for Gut Function Recovery—Reply

In Reply Dr Trocheris-Fumery and colleagues are correct to highlight the uncertainties and variation in practice in IV lidocaine dosage in the context of perioperative infusion in colorectal and other abdominal surgery. Our clinical trial was a pragmatic evaluation of an intervention that has gained credence despite an absence of robust dose-response studies for perioperative recovery end points. The relationship between infusion rate and serum lidocaine levels is affected by many variables as well as body weight; available data suggest that lidocaine infusion rates between 1.5 and 3 mg/kg/h appear to achieve similar serum lidocaine concentrations. Although our loading dose and infusion schedule was within accepted practice for this intervention, to prioritize safety we used ideal body weight rather than total body weight, given data suggesting increased serum levels in patients with obesity using total body weight. The currently recruiting VAPOR-C and LOLLIPOP trials evaluating perioperative IV lidocaine also use a dosage schedule modified for excess weight (adjusted body weight and ideal body weight, respectively).