8. Effect of dexmedetomidine as anaesthetic adjuvant in patients undergoing trans-sphenoidal pituitary surgery

Abstract

Background: We conducted a prospective, randomized, double-blind, placebo-control study to evaluate use of dexmedetomidine as anaesthetic adjuvant in patients undergoing trans-sphenoidal pituitary surgery. We tried to find its effect in attenuating hemodynamic response to nasal speculum insertion and on early postoperative recovery profile and intra operative consumption of anaesthetic agents. Materials and Methods: After obtaining approval from ethics committee, we enrolled 60 adult patients of either sex belonging to ASA-status I and II planned to undergo elective trans-sphenoidal pituitary surgery. Routine investigations and preoperative assessment was done as a standard protocol and injection glycopyrrolate 0.2 mg intramuscularly was administered 30 min prior to surgery. In group D (n = 30) dexmedetomidine 1 mcg/kg over 10 minutes followed by 0.5 mcg/kg/hr was given in infusion while in group C ( n = 30) normal saline ran in the same rate. Induction of anesthesia was achieved with sleep dose of propofol, fentanyl 2 mcg/kg and rocuronium 1mg/kg. Monitoring for heart rate, ECG, non-invasive and invasive blood pressure, oxygen saturation, end-tidal carbon di-oxide, BIS, along with neuromuscular monitoring was carried out. Peri-operative hemodynamic parameters were recorded and any fluctuation (increase or decrease) were treated as per protocol. The total dose of anesthetics, analgesics, muscle relaxant, and other drugs (anti-hypertensive’s) used were noted. The duration of anesthesia, surgery, nasal speculum duration and intraoperative fluids, blood loss and urine output were also recorded. Any adverse event or complication if occurred was noted. After conclusion of surgery, neuromuscular blockade was reversed and recovery profile (emergence time, extubation, time for visual examination, time for first analgesic, modified aldrete score, VAS score, Ramsay sedation score, postoperative nausea and vomiting and shivering) were recorded. The data was compiled and analyzed using SPSS for Windows version 20. Results: Our study demonstrated that patient in dexmedetomidine group had significant reduction in hemodynamic response to nasal speculum insertion and had perioperative hemodynamic stability. There was reduction in anaesthetic, analgesic, muscle relaxant consumption in group D. Emergence time and extubation time was less, and there were fewer episodes of postoperative nausea and vomiting and shivering in group D. VAS was less and time for first analgesic was prolonged in patients of dexmedetomidine group. There were few incidences of side-effects like bradycardia and hypotension. Conclusion: We conclude that dexmedetomidine as anesthetic adjuvant is efficacious in attenuating nasal speculum response, provides intraoperative hemodynamic stability, decreases intraoperative anaesthetic requirement and hastens early recovery without any serious side-effects.