DURATION OF BLOCKADE OF PERIPHERAL NERVES WITH LOW CONCENTRATED BUPIVACAINE SOLUTION DEPENDING OF THE ADJUVANTS

Abstract

Background. In recent years, anesthesiology has shown a tendency to reduce the use of narcotic analgesics intra- and postoperatively. This is due to respiratory depression and as a result – hypoxia in the postoperative period. In addition, the use of narcotic analgesics does not allow the patient to mobilize in the early postoperative period, which in turn increases the risk of thromboembolic complications, especially in elderly patients and patients with obesity. However, withdrawal from a narcotic analgesic should not affect the patient’s postoperative comfort and pain-relief. The rapid progress in the development of regional methods of analgesia has significantly reduced the use of narcotic analgesics intra and post operatively and has provided sufficient pain relief for patients. Despite the results achieved, we continue to search for the perfect combination of local anesthetic and adjuvants to ensure long-lasting and safe analgesia.Objective. Suggest a new combination of local anesthetics and adjuvants, compare the duration of postoperative analgesia after peripheral nerve blocks with low concentration bupivacaine solution with dexamethasone and low concentration bupivacaine with dexamethasone and epinephrine. Explore the possibility of orthopedic surgery without using narcotic anesthetics.Materials and methods. Seventy peripheral nerve blocks were performed in patients undergoing orthopedic surgery at Rivne Oblast State Hospital. Patients were randomly assigned to two groups, depending on the adjuvant to the local anesthetic: Group 1 – patients whose blockade was performed with solution of bupivacaine 0,375% and dexamethasone 0,02%; Group 2 – patients whose blockade was performed with a solution of bupivacaine 0,375% with dexamethasone 0,02% and epinephrine 0,00018%. The duration of the blockade was estimated by puncturing the skin with a needle. Pain intensity was assessed at the 6th, 12th, 24th and 36th hours after blockade using a VAS scale. The amount of narcotic anesthetic used in the postoperative period were also recorded. In addition, patients underwent electromyography of the innervation area of the blocked nerve before the surgery and 24 and 36 hours after surgery.Results. The duration of blockade in Group 2 was longer by 10 hours, the intensity of pain (VAS) was significantly higher after 24 hours (1.65 ± 1.35 in Group 2 and 5.3 ± 1.26 in Group 1). According to electromyography, 24 hours after the blockade conductance in Group 1 was restored by 95-100%, unlike Group 2, where conductivity was restored by only 47-59%.Conclusions. The proposed combination of local anesthetics and adjuvants provides both adequate anesthesia during surgery and prolonged post-operative analgesia.