Blood pressure and heart rate changes during intubation: a comparison of direct laryngoscopy and a fibreoptic method

Blood pressure and heart rate changes during nasotracheal intubation under general anaesthesia were studied in 100 patients who were randomly allocated to fibreoptic bronchoscope or direct laryngoscopy intubation. Noninvasive blood pressure and heart rate were recorded before and immediately after anaesthesia induction, at anaesthesia intubation and every minute thereafter for 5 min. Nasotracheal intubation was accompanied by significant increases in blood pressure and heart rate compared to baseline values in both groups. Blood pressure and heart rate at intubation, and the maximum values of blood pressure during the observation were significantly higher in the fibreoptic bronchoscope group. However, the maximum values of heart rate were not significantly different between the two groups. Fibreoptic nasotracheal intubation may result in more severe pressor and tachycardiac responses than direct laryngoscopic nasotracheal intubation.