Anesthesiological management of thyroidectomy in patients with thyrotoxicosis: the optimization of opioid-sparing effect and antiemetic component

AIM: assessment of opioid-sparing effect and antiemetic component of bilateral blockade of superficial cervical plexus under general anesthesia by sevoflurane or propofol in a complex of anesthetic management of patients undergoing thyroidectomy in a specialized centre of endocrine surgery. MATERILS and METHODS. All patients were divided into 2 groups: in a group of balanced analgesia (BA) were included 79 patients with thyrotoxicosis, in whom were used the balanced (multimodal) analgesia(BMMA) complex and the control group (C), which consisted of 87 patients with thyrotoxicosis, whom were used traditional anesthesia complex without the BMMA. Depending on the type of general anesthesia: an inhalation anesthesia by sevoflurane (S) or TIVA by propofol infusion (P) patients were divided into subgroups: subgroup BA-S included 35 patients, subgroup BA-P - 44 patients, subgroup C-S - 46 patients, and subgroup C-P - 41 patients. In the subgroups BA-S and BA-P were applied the complex BMMA, which included iv dexamethasone, iv dexketoprofen and bilateral blockade of superficial cervical plexus (BBSCP) by 0.5% bupivacaine. Author evaluated the pain level by visual analog score (VAS), the using of narcotic and non-narcotic analgesics, the frequency and severity of postoperative nausea and vomiting (PONV) during the first 24 hours of postoperative (post-op) period. RESULTS AND DISCUSSION. The combination of the bilateral BSCP with sevoflurane anesthesia reduces of an opioid requirement and opioid consumption in the intraoperative period. Subgroups BA-S and BA-P were not necessity to use of narcotic analgesics in the post-op period unlike subgroups C-S and C-P, where narcotic analgesics were used in 94,9% and 93,7% patients respectively. Because the BBSCP provides the high efficiency of post-op analgesia for a long time. According to VAS the level of pain in subgroups BA-S and BA-P was evaluated as a weak pain and was significantly (p<0,05) lower compare to the subgroups C-S and C-P. The use of the suggested complex BMMA with the basic anesthesia by sevoflurane in the subgroup BA-S provides the intraoperative opioid sparing effect, which means the decreasing of opioid consumption. We had of the level of intraoperative fentanyl consumption in 303,4±14,4mcg per operation, which was significantly lower by 19,5%, 20,5% and 31,6% than in the subgroups of C-S, BA-P and C-P respectively. The BMMA complex allowed us to improve (p <0,05) of management of the PONV. Number of patients without PONV was 45,7% and 51,2% in the subgroups C-S and C-P, respectively, and 74,3% and 77,3% in subgroups BA-S and BA-P. The significant decline (p<0,05) was reached in the total score on the PONV scale in the subgroups BA-P till 0,36 ± 0,11, that was on 60,6% and 55,2% less than in the subgroups of C-S and C-P. For the subgroup of BA-S, this indicator was 0,43±0,11 and was on 53,1% and 46,7% significantly (p <0,05) lower than in the subgroups C-S and C-P. CONCLUSIONS. The introduction of the BMMA complex into anesthetic management of patients with thyrotoxicosis, who undergoing the thyroidectomy, in the form of bilateral blockade of superficial cervical plexus by 0,5% bupivacaine solution with the addition of IV dexamethasone 4-8 mg and IV 50 mg dexketoprofen before induction of anesthesia has provided a high level of analgesia in post-op period in the both subgroups: with the baseline inhalation anesthesia by sevoflurane and with TIVA by propofol; has provided opioid-sparing effect in post-op period of due to lack of demand in the use of narcotic analgesics; has reduced post-operative pain and the frequency and severity of PONV, NSAIDs consumption.