ADJUVANT SPINAL ANESTHESIA AS AN EFFECTIVE APPROACH TO POSTOPERATIVE PAIN MANAGEMENT IN ABDOMINAL HYSTERECTOMY: A COMPARATIVE CLINICAL STUDY

Abdominal hysterectomy (AH) is one of the most common gynecological operations in the world. A characteristic feature of interventions on the pelvic organs is intense nociceptive stimulation, the formation of deep somatic and visceral pain, which requires effective analgesia strategies, especially in the first 24 hours after surgery. According to the literature, postoperative pain on day 1 in AH reaches 6.47 points on the NRS (Numeric rating scale) and takes 4th place in the rating of pain intensity after various surgical interventions. Recent years have been marked by an increase in scientific interest in the influence of anesthesia technique on the severity of pain syndrome in the early postoperative period and the formation of chronic postoperative pain syndrome. It becomes expedient to compare various strategies and determine the most effective, safe and patient-oriented model of analgesia. Adjuvant spinal anesthesia (ASA) has attracted considerable attention, as it allows to provide not only high-quality sensory block during the operation, but also a prolonged analgesic effect in the postoperative period. Objective of the study: To compare the effectiveness and safety of three methods of anesthetic provision – spinal anesthesia with bupivacaine (SAB), adjuvant spinal anesthesia with morphine, fentanyl, dexamethasone (ASA) and multimodal low-opioid analgesia (MLOA) for the management of postoperative pain in patients after abdominal hysterectomy. Material and methods. The prospective study included 118 women aged 40–65 years, ASA I – II, who underwent abdominal hysterectomy in compliance with the basic biotic provisions of the Council of Europe Convention on Human Rights and Biomedicine, the Declaration of Helsinki of the World Medical Association on the ethical principles of conducting scientific medical research involving human participants. The study protocol was approved at the meeting of the Biomedical Ethics Commission of the P.L. Shupyk National Medical Academy of Postgraduate Education (protocol No. 1 dated 09.01.2023). Depending on the type of anesthesia used, all patients were randomly assigned to three randomized groups: Group 1 (MLOA; n=47): multimodal low-opioid general anesthesia; Group 2 (SAB; n=33): spinal anesthesia with bupivacaine + sedation with propofol; Group 3 (ASA; n=38): adjuvant spinal anesthesia, where in addition to bupivacaine, morphine + fentanyl and dexamethasone were administered intrathecally, and sedation was provided by dexmedetomidine infusion. All procedures were performed according to a standard protocol. The studies were performed at the following stages: 1; 3; 6; 12 and 24 hours after surgery. Pain intensity was assessed using a visual analog scale (VAS), the time to the first morphine administration, its daily requirement, side effects (postoperative nausea and vomiting (PONV), tremor, skin itching) were recorded. Statistical processing of the obtained data was carried out using the Statistica for Windows 14.0 software package (TIBCO Statsoft Inc., USA). Results. ASA showed the best results in terms of pain reduction during the first 12 hours of the postoperative period and the lowest need for systemic opioids (morphine) 6.4 ± 5.7 mg/day compared to the MMZA and SAB groups, where the need for opioids was 14.4 ± 7.7 mg/day and 15.4 ± 8.7 mg/day, respectively. The longest quality analgesia was observed in patients of group 3 – 342.1 ± 53.7 minutes (5.7 hours) and was significantly longer, including in comparison with the SAB group (t = –22.01; p < 0.001). Patients of the MMZA group had a significantly shorter time to morphine administration compared to patients of the SAB and ASA groups. Patients in the SAB group had significantly more postoperative shivering (18.2%), and in the ASA group, skin itching was more often recorded (15.8%). Despite the intrathecal administration of opioids, the frequency of PONV was the same in all comparison groups. Conclusions: adjuvant spinal anesthesia is the optimal method of postoperative analgesia in hysterectomy due to its prolonged effect, better pain control, and reduced need for systemic opioids, which is consistent with the ERAS principles.