Abstract: | The authors determined the cardiovascular effects of blind nasotracheal intubation in four randomized groups of 25 patients each. After induction of anaesthesia with IV thiopentone 4 mg X kg-1, patients in group A received no pretreatment, while patients in group B received IV lidocaine 1.5 mg X kg-1. Three minutes before induction, patients in group C received 0.25 per cent phenylephrine nasal spray (0.2 mg in each nostril); those in group D received ten per cent lidocaine nasal spray (30 mg in each nostril). After intubation, mean arterial pressures (MAP) were highest in group B (IV lidocaine) patients (p less than 0.05), remaining significantly elevated for 5 min. Conversely, within four minutes after intubation, MAP of group D (ten per cent nasal lidocaine spray) patients were below control (p less than 0.05), and lower than those of any other group (p less than 0.05). MAP of group A and C patients increased after intubation, but not as much as in group B patients (p less than 0.05). There were no adverse effects from the lidocaine nasal spray. Ten per cent lidocaine nasal spray is a safe and effective way to minimize the MAP increases which typically accompany blind nasotracheal intubation in lightly anaesthetized patients. |