The effect of esmolol infusion as an adjunct to totalintravenous anesthesia on the total anesthetic and analgesicrequirements in arthroscopic shoulder surgery

Background Esmolol is the first intravenous, short-acting, titratable β-blocker for use in critical care and surgical settings. It influences core components of an anesthetic regimen, such as analgesia, hypnosis, and memory function.AimsTo investigate whether perioperative esmolol infusion as an adjuvant to total intravenous anesthesia could affect the total anesthetic and analgesic requirements in adult patients undergoing arthroscopic shoulder surgery.Settings and designA randomized, double-blinded, prospective study.Materials and methodsEighty adult ASA I and II patients scheduled for elective arthroscopic rotator cuff repair were randomized into the esmolol group (n = 40) and the control group (n = 40). In the esmolol group, 1 mg/kg esmolol was given as a bolus over 30 s, followed by 15 μg/kg/min as an intravenous infusion, and in the control group, the same volume of normal saline was given during the same time period. The heart rate, the mean arterial blood pressure, the depth of anesthesia, the duration of anesthesia, the recovery time, total anesthetic requirements, the postoperative pain score (VAS), and the total postoperative analgesic requirements were monitored and calculated during the perioperative period.ResultsThere was no significant difference between both groups regarding the demographic data using the unpaired t-test. There was a significant difference between both groups (P 0.05) regarding different parameters, except the duration of anesthesia, using the unpaired t-test. Preoperative mean values of heart rate (beats/min) and the mean arterial blood pressure (mmHg) were comparable between the two groups (P 0.05). However, after induction of anesthesia and thereafter, there was a significant reduction in heart rate and mean arterial blood pressure mean values in the esmolol group when compared with the control group (P 0.05). A significant change in bispectral index was noticed within each group in comparison with the baseline using the paired t-test. However, there was no significant difference between both groups. Postoperative pain assessments by VAS (0–100 mm) showed significantly lower pain scores in the esmolol group compared with the control group by the paired t-test (P 0.05). There was a highly significant reduction (P 0.001) in the total cumulative doses of morphine consumption by PCA during the first 24 h in the esmolol group compared with the control group. ConclusionPerioperative esmolol infusion reduces the total anesthetic and analgesic requirements andpostoperative pain. Hence, esmolol can be considered as safe and suitable adjuvant to totalintravenous anesthesia.