The Effect of Intravenous Lidocaine on the Increase in Ocular Pressure Induced by Tracheal Intubation

Kim, Yong Lak; Min, Seong Won

Abstract

This study was undertaken to determine whether intravenous lidocaine could prevent the acute increase in intraocular pressure associated with laryngoscopy and tracheal intubation. Twenty surgical patients(ASA class 1) who do not have any disease influencing on the intraocular pressure(IOP)(e.g. ophthalmic diseases, diabetes, hypertension, etc.) were studied and divided into two groups, experimental group(n= 10) and control group(n=10). After measurement of preinduction IOP, anesthesia was induced by pentothal 5 mg/kg and vecuronium 0.15 mg/kg, and maintained with 100% oxygen for 3 minutes and baseline IOP was measured. Then, saline and lidocaine(1.5 mg/kg) were injected to controls and experimental group, respectively. One minute and 30 seconds after this, IOP was measured and trachea was intubated. After intubation, anesthesia was maintained with 100% oxygen and 1,5 vo1% halothane and IOP was measured on 1, 3 and 5 minutes after intubation. The results were as follows. 1) One minute and 30 seconds after saline or lidocaine injection(immediately before intubation), IOP was significantly lower in lidocaine group than control group. 2) Peak increases in IOP after intubation were significantly less in lidocaine group than control group. From the above results, the use of 1.5 mg/kg of intravenous lidocaine approximately 1 minute and 30 seconds before tracheal intubation significantly attenuates the increase in IOP. This procedure will be useful in the induction of anesthesia in patients in whom the increase in IOP should be avoided.