Increased postoperative dexamethasone and gabapentin reduces opioid consumption after total knee arthroplasty

摘要

PurposeDexamethasone and gabapentin are used in multimodal pain management protocols to reduce postoperative pain after total knee arthroplasty. For both analgesic adjuvants, the optimal dose regimen to reduce opioid usage is still unclear.MethodsThe opioid consumption of patients undergoing primary TKA before and after a change of the analgesic adjuvant medication in our protocol (old protocol: 4mg of dexamethasone daily for 2days, 600mg gabapentin daily for 1week; new protocol: 10mg dexamethasone daily for 2days, 300mg gabapentin every 8h for 1week) were retrospectively compared. All surgeries were performed under spinal anesthesia. Peri- and postoperative pain medication remained unchanged.ResultsA total of 186 patients who received TKA between 11/29/2016 and 06/09/2017 were screened. Six patients who received general anesthesia, 4 patients who underwent simultaneous bilateral TKA, and 16 patients with ongoing opioid consumption at the time of surgery were excluded, leaving 80 patients in each group. Opioid consumption within 24h [morphine equivalents in mg: mean 50.5, standard deviation (SD) 30.0 (old) vs. 39.8, SD 24.2 (new); P=0.0470], cumulative consumption over 48h (97.3, SD 64.4 vs. 70.4, SD 51.2; P=0.0040) and cumulative consumption over 72h (108.1, SD 79.5 vs. 82.5, SD 72.6; P=0.0080), were all significantly lower in the new protocol.ConclusionIncreased postoperative administration of dexamethasone and gabapentin after TKA is associated with lower opioid consumption. Within the first 48h, up to about 25% of opioids can be spared, comparing high-dose to low-dose protocols.Level of evidenceTherapeutic Level III.