Dose optimization of intravenous dexamethasone for total knee arthroplasty: when two is not better than one

Background The optimal dose regimen of dexamethasone in total knee arthroplasty (TKA) has not been determined. This study was performed to evaluate the impact of a single preoperative high-dose dexamethasone compared with two perioperative low-dose dexamethasone in TKA. Materials and methods We prospectively studied three regimens on dexamethasone: no dexamethasone (A), a single preoperative dose of 20-mg dexamethasone (B), and two perioperative doses of 10-mg dexamethasone (C). The primary outcome was postoperative pain level. The incidence of postoperative nausea and vomiting (PONV), use of analgesic and antiemetic rescue, interleukin-6 (IL-6) and C-reactive protein (CRP) levels, range of motion (ROM), and complications were also compared. Results The dynamic pain scores and CRP and IL-6 levels were significantly lower for Group B compared to Groups A and C on postoperative days 1 and 2 (POD 1 and 2). Such differences were also detected between Groups C and A. Besides, the pain scores at rest were significantly lower in Groups B and C than in Group A on POD 1 and 2. Patients in Groups B and C had a lower incidence of PONV, reduced use of analgesic and antiemetic rescue, and improved ROM than in Group A. No complications occurred in any group. Conclusion Dexamethasone in TKA provides short-term advantages in analgesic, antiemetic and anti-inflammatory effects. Besides, regarding the effects of pain and inflammatory control on POD 1 and 2, a single preoperative high dose of 20-mg dexamethasone was more effective than two perioperative low doses of 10-mg dexamethasone.