BACKGROUND: The aim of this study was to compare the cardiovascular changes followed by laryngoscopy with the McCoy laryngoscope blade with those followed by laryngoscopy with the Macintosh laryngoscope blade. METHODS: Forty eight patients were randomly divided into two groups. Following induction with fentanyl 2 mcg/kg and thiopental 5 mg/kg, and muscle relaxation with vecuronium 0.1 mg/kg, the vocal cords were visualized with either the McCoy or the Macintosh laryngoscope blade, then tracheal intubation was performed. Heart rate and arterial blood pressure were measured just before and after laryngoscopy, and 1, 3 and 5 min later. RESULTS: There was a significant increase in both heart rate and arterial blood pressure after tracheal intubation using the Macintosh laryngoscope. Also, use of the McCoy blade resulted in a significant increase in both heart rate and arterial blood pressure. CONCLUSIONS: There was no significant difference on arterial pressure and heart rate to laryngoscopy and tracheal intubation with either the McCoy blade or the Macintosh.