Effects of Preoperative Carbohydrate-rich Drinks on Immediate Postoperative Outcomes in Total Knee Arthroplasty: A Randomized Controlled Trial

Background: This study investigates the effects of preoperative carbohydrate-rich drinks on postoperative outcomes after primary total knee arthroplasty. Methods: We prospectively randomized 153 consecutive patients undergoing primary total knee arthroplasty at one institution. Patients were assigned to one of three groups: group A (50 patients) received a carbohydrate-rich drink; group B (51 patients) received a placebo drink; and group C (52 patients) did not receive a drink (control). All healthcare personnel and patients were blinded to group allocation. Controlling for demographics, we analyzed the rate of postoperative nausea and vomiting, length of stay, opiate consumption, pain scores, serum glucose, adverse events, and intraoperative and postoperative fluid intake. Results: Demographics and comorbidities were similar among the groups. There were no significant differences in surgical interventions or experience. Surgical fluid intake and total blood loss were similar among the three groups ( P = 0.47, P = 0.23). Furthermore, acute postoperative outcomes (ie, pain, episodes of nausea, and length of stay) were similar across all three groups. There were no significant differences in adverse events between the three groups ( P = 0.13). There was a significant difference in one-time postoperative bolus between the three groups ( P = 0.02), but after multivariate analysis, it did not demonstrate significance. None of the intervention group were readmitted, whereas 5.9% and 11.5% were readmitted in the placebo and control groups, respectively ( P = 0.047). The chance of 90-day readmission was reduced in group A compared with group C (odds ratio, 0.08; 95% confidence interval, 0.01 to 0.72; P = 0.02). There were no differences in other postoperative outcome measurements. Conclusion: This randomized controlled trial demonstrated that preoperative carbohydrate loading does not improve immediate postoperative outcomes, such as nausea and vomiting; however, it demonstrated that consuming fluid preoperatively proved no increased risk of adverse outcomes and there was a trend toward decrease of one-time boluses postoperatively. Clinical Trials Registry: NCT03380754