Background: Pain syndrome in patients with various types of coxarthrosis after endoprosthetics is an urgent problem that is far from a final solution.

Purpose of the study: Use of dexmedetomidine to optimize perioperative pain relief in patients after major joint replacement.

Material and research methods: The study was conducted in the surgical clinic of the AMU. The study included 89 patients who underwent endoprosthetics in patients with various types of coxarthrosis. Inclusion criteria were age 45-95 years and American Society of Anesthesiologists (ASA) physical status class I-III. All patients underwent general anesthesia. The patients were divided into 2 groups. In patients of group I, surgical interventions were performed only under general anesthesia, and in group II, dexmedetomidine was included in the general anesthesia regimen. In group II, patients received demedetomidine at a dose of 1 mcg/kg for 10 minutes (loading dose), and then 0.2-0.7 mcg/kg/hour for a maintenance dose. Pain severity was determined using a numeric rating scale (VAS) ranging from 0 (no pain) to 10 (worst pain). If the patient reported pain at the surgical site as greater than 3, then an intravenous mixture was started that included 50 μg of fentanyl in 50 ml of 0.9% saline at a rate of 1 ml/hour with a bolus dose of 1 ml. The time to the first complaint of pain was recorded, and patients with a VAS score of more than 3 points were administered the narcotic analgesic trimeperidine 20 mg. Despite this protocol for the administration of analgesics, if the patient complained of pain more severe than the VAS pain score of more than 4 points, trimeperidine 20 mg was administered intravenously. The quality of pain was assessed at 8, 16 and 24 hours after surgery and included in the table.

Results: Patient characteristics were comparable between the two groups. The postoperative cumulative dose of intravenous trimeperidine was significantly lower in the group of patients whose anesthesia regimen included dexmedetomidine (0.01 [0.01-8.0 mg]) than in the group without dexmedetomidine (10.3 [6.5] -12.5 mg]) at 16 hours (median difference 7.83 [5.2-11.6 mg]) and at 24 hours 5.72 mg. Postoperative consumption of non-opioid analgesics was comparable between the two groups (p=0.542).

Conclusions: Intravenous dexmedetomidine significantly reduces postoperative opioid use during the first 24 hours after surgery and increases the duration of postoperative pain relief in patients undergoing surgery for large joint arthrosis.

Keywords: coxarthrosis, endoprosthetics, dexmedetomidine, multimodal pain relief