SummaryBlood 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.

SummaryThe circulatory responses to laryngoscopic tracheal intubation in 62 healthy children undergoing surgery requiring tracheal intubation were studied. They were randomly assigned to receive either the oral or nasal route for intubation. Baseline non-invasive blood pressure and heart rate were recorded following induction of anaesthesia, at intubation and then every minute for 5 min. The percentage changes of systolic blood pressure and heart rate during the measurement period were calculated. The results demonstrated that intubation time was significantly longer in the nasal group. Both oral and nasal intubation caused significant increases in blood pressure and heart rate compared to baseline and postinduction values. However, there were no significant differences found between the two groups in relation to blood pressure and heart rate. The two groups were similar with respect to the percentage changes of systolic blood pressure and heart rate during the observation period. It is concluded that oral and nasal intubation using a direct laryngoscopy can result in a similar circulatory response in anaesthetised children. Laryngoscopy and tracheal intubation in anaesthetised children is often associated with hypertension and tachycardia [1]. This may be the result of reflex sympathetic activation, perhaps involving the baroreceptor system provoked by airway nociceptive stimulus. It has been shown that different phases of the intubation process can cause different degrees of circulatory response [2,3], as indeed does mechanical stimulation of different sites in the airway [4]. Nasotracheal intubation can stimulate the nasal cavity and nasopharynx, which does not occur during orotracheal intubation. Previous studies in anaesthetised adults have demonstrated that simple nasopharyngeal intubation and insertion of a nasopharyngeal airway can produce significant hypertensive responses [5,6] and the circulatory responses to laryngoscopic nasal intubation are greater than those produced by oral intubation [7,8]. To the best of our knowledge, no previous study in children has compared the circulatory responses of these two intubation routes in a single clinical trial. Therefore, this randomised clinical study was designed to determine whether there was a clinically relevant difference between the circulatory responses produced by nasal and oral intubation performed by experienced practitioners in healthy anaesthetised children. MethodsFollowing institutional ethics committee approval and written informed parental consent, 62 ASA physical status 1 children, scheduled for elective plastic surgery requiring general anaesthesia with tracheal intubation were included in this study. Exclusion criteria included a history of reactive airway disease, gastro-esophageal reflux, morbid obesity, hypertension, and the use of medications known to affect blood pressure and heart rate. Children were randomly allocated to either the oral or the nasal group using a sealed envelope method.Prior to surgery, all children fasted overnight a...

When used as part of anaesthesia induction with propofol and vecuronium in children, bolus administration of remifentanil resulted in a dose-related attenuation of the cardiovascular intubation response.