Effect of lidocaine injection via endotracheal tube on incidence of cough and laryngospasm

Aims. Coughing during unconseusness or after tracheal extubation is unwanted and possible that can be harmful in patients under cataract operation and cause damages to eye or finally blindness. Our goal in this study was to determine the effect of lidocaine injection via endotracheal tube before extubation in decrease of incidence of cough and laryngospasm in cataract operation after extubation. Methods. This is a double blind randomized clinical trial study, performed for 6 months in Yasouj Emam-Sajad Hospital on 66 above 18 year-old candidates of cataract operation. In control group, 100 mg (5ml) of lidocaine 2% and in test group, same volume of placebo (normal salin) injected via endotracheal tube. Using anesthesia drugs stoped 5 to 10 minutes before end of the surgery and after ending the operation extubation took lace. The number of coughs and laryngospasm recorded in three periods. Collected data analysed by SPSS 11. Results. Cystolic and diastolic blood pressure before operation, after extubation in operation room and in recovery room did not show a significant different in control and test group. Number of coughs were higher in control group and the difference between 2 groups were significant. Conclusion. Administration of lidocaine via endotracheal tube administration reduces coughing during emergence from general anesthesia without prolonging the emergence in cataract operation.