Effects of continuous endotracheal-laryngopharynx topical anesthesia on the general anesthetic requirements during surgery

The purpose of this study was to investigate the general anesthetic requirements in patients with continuous endotracheal-laryngopharynx topical anesthesia using medicine injecting endotracheal tube during surgery. A total of 78 patients with American Society of Anesthesiologists (ASA) physical status I–II were randomly divided into test group and control group. After anesthesia, patients were injected by 1.5 mL of 1% Tetracaine for topical anesthesia, and later injected similarly at hourly intervals during surgery while patients in control group were non-injected. There was no statistical significance in values of SBP, DBP, MAP, HR and plasma concentrations of E, NE and Cor at same time point between the two groups during operation (P>0.05). There was no statistical significance in value of BIS at T(0)-T(5) between the two groups (P>0.05). However, value of BIS at T(6) in test group was significantly higher than that in control group (69.7±2.1 vs. 58.6±2.3, P<0.01). Doses of sevoflurane, propofol sufentanil and cisatracurium used up in test group decreased by 12.3% (P<0.01); 12.7% (P<0.01); 14.5% (P<0.01) and 4.9% (P>0.05) than those in control group, respectively. Continuous endotracheal-laryngopharynx topical anesthesia using 1% Tetracaine via medicine-injecting endotracheal tube can significantly decrease general anesthetic requirements of surgery.