[Effect of perioperative dexamethasone on nausea, vomiting and pain after total knee arthroplasty]

To investigate the effect of perioperative dexamethasone on nausea, vomiting and pain after unilateral total knee arthroplasty and to evaluate its safety.

From February 2014 to June 2016, 100 patients with unilateral advanced osteoarthritis treated by total knee arthroplasty were divided into two groups: 50 patients in dexamethasone group including 27 males and 23 females, aged (72.30±7.02) years, were given intravenous drip of dexamethasone 10 mg before operation; 50 patients in saline group, including 26 males and 24 females, aged (71.30±6.08) years, were given the same amount of saline at the corresponding time. The VAS scores of pain at rest and at 45 degrees of knee flexion were recorded at 2, 4, 6, 8, 12, 24, 36 and 48 h after operation. Vomiting, antiemetic drugs and opioids were recorded at 0 to 24 h and 24 to 48 h after operation. The side effects and complications were recorded.

All the 100 patients were followed up for an average of 14.5 months. VAS score of pain at rest in dexamethasone group was lower than that in saline group at 8, 24 and 48 h after operation (P<0.05); VAS score of dexamethasone group at 45 degrees after knee flexion was lower than that of saline group at 8 and 48 h after operation(P<0.05); VAS score of dexamethasone group at rest and 45 degrees after knee flexion was lower than that of saline group(P<0.05). The dosage of opioids and total opioids in dexamethasone group was lower than that in saline group at 0 to 24 h, 24 to 48 h after operation (P<0.05). The proportion of nausea and vomiting occurred at 0 to 24 h and 24 to 48 h after operation, and the proportion of antiemetic required at 0 to 24 h after operation had statistical significance between two groups(P<0.05). The total antiemetic dosage of dexamethasone group was less than that of saline group(P<0.05). As of the last follow-up, no complications such as infection, gastrointestinal ulcer and bleeding occurred in the two groups.

Preoperative systemic application of dexamethasone can effectively reduce pain and nausea and vomiting after TKA without increasing postoperative complications.