Effect of perioperative single dose intravenous vitamin C on pain after total hip arthroplasty

IntroductionVitamin c can relieve the pain after other diseases, but there are no studies on whether vitamin C can relieve the pain after hip replacement. The purpose of this paper is to study whether vitamin C can relieve the pain after total hip replacement.PurposeIn this prospective, double-blind, placebo-controlled, randomized trial, 100 patients receiving THA at our hospital were randomly assigned to vitamin c or control groups. During the operation, the vitamin C group will receive intravenous injection of 3 g vitamin C, and the control group will receive 3 g placebo. If the patient has postoperative pain, 10 ml subcutaneous injection of morphine will be required as a rescue analgesic. The primary outcome was the amount of postoperative injection of morphine as a rescue analgesic and expression of inflammatory factors, and the secondary outcome was postoperative pain and hip recovery as assessed by visual analog scale (VAS).ResultsThe dosage of subcutaneous injection of morphine was significantly reduced in vitamin C group. VAS pain scores at rest and exercise were lower in the vitamin C group 24 h after surgery, and hip motion was better 24 h after surgery, but there was no significant difference between the two groups 24 h after surgery.Nonetheless, the overall changes in morphine usage and VAS scores did not surpass the established minimal clinically important differences (10 mg for morphine consumption; 1.5 at rest and 1.8 during movement for VAS scores).ConclusionAdding intravenous vitamin c to multimodal analgesia significantly improved morphine consumption, VAS pain score, and functional recovery. However, it is recommended that single intravenous administration of vitamin C during the perioperative period may achieve better pain relief for patients after THA.