Gabapentin does not improve multimodal analgesia outcomes for total knee arthroplasty: a randomized controlled trial La gabapentine n’améliore pas l’analgésie multimodale pour l’arthroplastie totale du genou : une étude randomisée contrôlée

Purpose This study assessed whether gabapentin given preoperatively and for two days postoperatively (in addition to patient-controlled analgesia [PCA] morphine, acetaminophen, and ketorolac) is effective in reducing morphine requirements and moderating pain scores when compared with placebo for primary total knee arthroplasty. Methods This single-centre double-blind randomized controlled trial was undertaken in patients who underwent primary total knee arthroplasty. All subjects received acetaminophen 1,000 mg and ketorolac 15 mg po preoperatively. Postoperatively, subjects received PCA morphine, acetaminophen 1,000 mg every six hours, and ketorolac 15 mg po every six hours. Subjects received either gabapentin 600 mg po preoperatively followed by 200 mg po every eight hours for two days or matching placebo. The primary outcome was cumulative morphine consumption at 72 hr following surgery. Secondary outcome measures included pain scores and patient satisfaction. Results There were 52 subjects in the gabapentin group and 49 subjects in the placebo group. The average cumulative morphine consumption at 72 hr postoperatively was 66.3 mg in the gabapentin group and 72.5 mg in the placebo group (difference -6.2 mg; 95% confidence interval -29.1 to 16.8 mg; P = 0.59). Mean pain scores at rest, with passive movement, or with weight bearing were similar in both groups at corresponding time periods for the first three days following surgery. In addition, mean patient satisfaction scores and hospital length of stay were similar in the two groups. Conclusion Gabapentin 600 mg po given preoperatively followed by 200 mg po every eight hours for two days has no effect on postoperative morphine consumption, pain This report was previously presented, in part, at the Canadian Anesthesiologists’ Society Annual Meeting, June 2011. Author contributions James Paul, Manyat Nantha-Aree, Norman Buckley, Ji Cheng, and Lehana Thabane helped design the study. James Paul, Manyat Nantha-Aree, Norman Buckley, Justin DeBeer, Mitchell Winemaker, David Wismer, Dinshaw Punthakee, and Victoria Avram helped conduct the study. James Paul, Manyat Nantha-Aree, Norman Buckley, Ji Cheng, Lehana Thabane, Justin DeBeer, Mitchell Winemaker, David Wismer, Dinshaw Punthakee, and Victoria Avram helped write the manuscript. James Paul, Manyat Nantha-Aree, Norman Buckley, Ji Cheng, Lehana Thabane, and Antonella Tidy have seen the original study data. James Paul, Manyat Nantha-Aree, Norman Buckley, Ji Cheng, Lehana Thabane, Mitchell Winemaker, David Wismer, Dinshaw Punthakee, and Victoria Avram reviewed the analysis of the data. James Paul is the author responsible for archiving the study files. Ji Cheng and Lehana Thabane helped analyze the data. Antonella Tidy helped with data collection. J. E. Paul, MD M. Nantha-Aree, MD N. Buckley, MD J. Cheng, MSc L. Thabane, PhD A. Tidy, HBSc Department of Anesthesia, McMaster University, Hamilton, ON, Canada J. DeBeer, MD M. Winemaker, MD D. Wismer, MD D. Punthakee, MD V. Avram, MD Department of Surgery, McMaster University, Hamilton, ON, Canada J. E. Paul, MD (&) Hamilton Health Sciences, Department of Anesthesia (HSC-2U4), McMaster University, 1280 Main Street West, Hamilton, ON L8S 4K1, Canada e-mail: [email protected] 123 Can J Anesth/J Can Anesth (2013) 60:423–431 DOI 10.1007/s12630-013-9902-1