High dose dexamethasone in high pain responders undergoing total hip arthroplasty: A randomized controlled trial.

BACKGROUND:Postoperative pain after total hip arthroplasty (THA) may delay postoperative mobilization and discharge. Postoperative pain has been shown to be higher in pain catastrophisers and patients receiving opioids. A single dose of glucocorticoid reduces pain after THA, and an increased dose of glucocorticoids has been found to be effective in patients at high risk of postoperative pain after total knee arthroplasty (TKA), however, the ideal dose in THA remains unknown. OBJECTIVE:To evaluate the effect of a high dose (1 mg kg -1 ) vs. intermediate dose (0.3 mg kg -1 ) of dexamethasone on pain after THA. DESIGN:A randomized double-blind controlled study. SETTING:A two-centre study including two large arthroplasty sites in Denmark was conducted from February 2019 to August 2020. PATIENTS:A total of 160 patients undergoing THA by neuraxial block with multimodal analgesia, having a Pain Catastrophising Scale score >20 and/or preoperative opioid use were included. INTERVENTION:Patients were randomly assigned to receive dexamethasone 1 mg kg -1 or 0.3 mg kg -1 before THA. MAIN OUTCOME MEASURES:Primary outcome was percentage of patients experiencing moderate to severe pain (visual analogue scale, VAS > 30 mm on a 0 to 100 mm scale) on ambulating 24 h after surgery. Secondary outcomes included cumulated pain scores, C-reactive protein (CRP), opioid use, postoperative recovery scores, length of stay, complications, and re-admission within 30 and 90 days. RESULTS:No difference was found in percentage of VAS >30 mm 24 h after surgery in the 5-m walk test (VAS > 30/VAS ≤ 30%); 33/42 (44%) vs. 32/43 (43%), relative risk = 1.04 (95% confidence interval 0.72-1.51; P  = 0.814) in 1 mg kg -1vs. 0.3 mg kg -1 respectively. No differences were found in CRP and opioid use between groups. Also, no intergroup differences were found in recovery scores, re-admissions, or complications. CONCLUSION:1 mg kg -1vs. 0.3 mg kg -1 dexamethasone improved neither postoperative pain nor recovery in THA in a cohort of predicted high pain responders. TRIAL REGISTRATION:ClinicalTrials.gov ID-number NCT03763760 and EudraCT-number 2018-2636-25.