Evidence-based Practice and Quality Improvement
Background and Goal: During endoscopic sinus surgery (ESS), excessive bleeding makes surgery difficult due to poor visibility and increases the incidence of complications. Many drugs have been described to induce hypotension and to reduce bleeding in the surgical field 1. No drug has so far been demonstrated to be ideal and there is a need for further research. Dexmedetomidine is a highly specific alpha 2 - agonist with analgesic and sedative properties 2. The primary goal of this study was to assess effect of dexmedetomidine on Mean Arterial Pressure, the quality of surgical field and requirement of nitroglycerine or metoprolol for ESS during general anaesthesia.
Materials and Methods: This prospective, randomized, double blind study was conducted in 60 ASA III patients of either sex, of age 18-60 years, scheduled for elective ESS under General anaesthesia. Thirty patients in Group I (Dexmedetomidine Group) received dexmedetomidine 1 μg/kg bolus, 10 min before induction of anaesthesia and 0.5 μg /kg/h infusion during maintenance. Group II (Control Group) received Normal saline with same dosage schedule. Mean arterial pressure was recorded intraoperatively and bleeding during surgery was assessed by the surgeon using Fromme Scale 3.
Results and Discussion: Mean arterial pressures (mm Hg) at induction, postinduction and 20 min post -induction were 76.46±8, 82.53±11.12 and 69.16±5.71 in dexmedeomidine group as compared to 89.29 ± 14.2, 93.58 ± 21.02 and 74.65 ± 9.96 in Control Group (P< 0.05). Amount of nitroglycerin required was significantly higher in Control Group (P < 0.05) than Dexmedeomidine Group. Fromme Scale Score was significantly lower in Dexmedtomidine Group than Control Group (P 0.011). No patient required metoprolol in Dexmedotomidine group. This may be explained due to sympatholytic, vagomimetic, and vasoconstrictive properties of dexmedtomidine.
Conclusion: Dexmedetomdine maintains optimal hypotension, offers better surgical field by reducing bleeding and minimizing the use of nitroglycerine or metoprolol.
1. Nair S, Collins M. Effect of β-blockers premedication on the surgical field during endoscopic sinus surgery. Laryngoscope 2004; 115: 144 1042-1046.
2. Paris A, Tonner PH. “Dexmedetomidine in anaesthesia”. Curr Opin Anaesthesiol. 2005;18 (4): 412-418.3. Fromme GA, MacKenzie RA, Lund BA et al. Controlled hypotension for orthognatic surgery. Anesth Analg 1986; 65: 683-686.