Abstract: Objective　To observe the clinical efficacy of nitroglycerin combined with esmolol in controlled hypotension during orthognathic surgery. Methods Sixty elderly, ASAⅠ-Ⅱ, patients who was to undergo orthognathic surgery were selected and randomly divided into two groups, according to random number table. In Group N, nitroglycerin was used alone during operation, while in Group NE, nitroglycerin combined with esmolol was used. Nitroglycerin of both group started from 4 μg?kg-1?min-1, esmolol started from 150 μg?kg-1?min-1. Controlled hypotension started 2 min before the osteotomy, stopped at the separation of maxillary. MAP，HR and CVP were recorded immediately before controlled hypotension(T0), at the goal of controlled hypotension(T1),5 min after achieving the goal(T2),5 min(T3)and 10 min(T4) after stopping controlled hypotension. The contents of hemoglobin and hematokrit before and after the operation were detected，the amount of bleeding was calculated, and the amount of nitroglycerin and the operation time were recorded. Results Compared with Group N, HR significantly decreased at T1 to T3,MAP significantly decreased at T1 , T3 and T4,the operation time was shorter, the amount of nitroglycerin was less(P＜0.05) in Group NE. The amount of bleeding and CVP had no statistically significant difference between two groups. Conclusions Nitroglycerin combined with esmolol in controlled hypotension is useful to shorten the amount of nitroglycerin, reduce the operative time , inhibit tachycardiac responses caused by nitroglycerin , so that it can meet the need of orthognathic surgery better.

Key words: Controlled hypotension, Nitroglycerin, Esmolol