[Hemodynamic responses to orotracheal intubation with fiberoptic bronchoscope and direct laryngoscope in children].

OBJECTIVE: To compare the hemodynamic responses to orotracheal intubation via fiberoptic bronchoscope (FOB) with conventional orotracheal intubation via direct laryngoscope (DLS) in children under general anesthesia.

METHODS: Forty-three American Society of Anesthesiologist grade I-II children undergoing the elective plastic surgery and requiring orotracheal intubation were randomly allocated to either the DLS group (n = 20)or the FOB group (n = 23). After standard intravenous anesthetic induction, orotracheal intubation was performed using a DLS or a FOB. Noninvasive systolic blood pressure (SBP), diastolic blood pressure (DBP), heart rate (HR), and rate-pressure product (RPP) were recorded before and after anesthetic induction, at intubation, and 5 minutes after intubation with 1 minute interval.

RESULTS: In the DLS group, SBP, HR, and RPP at intubation increased significantly compared to their postinduction values (P < 0.05),but blood pressure, HR and RPP at intubation didn't differ from their preinduction values. The maximal values of SBP, HR and RPP during the observation (from the beginning of intravenous anesthetic induction to 5 minutes after intubation) were significantly higher than their preinduction values (P < 0.05). In the FOB group, blood pressure, HR and RPP at intubation increased significantly compared to their preinduction and postinduction values (P < 0.05), and the maximal values of blood pressure, HR and RPP during the observation were significantly higher than their preinduction values (P < 0.05). There were no significant differences in blood pressure and RPP at each time point during the observation between the two groups. The HR at intubation were significantly higher in the FOB group than in the DLS group (P < 0.05), but no significant difference was observed in the HR values at other time points during the observation between the two groups. There were also no significant differences in the maximal values of blood pressure, HR and RPP or the times to reach their maximal values between the two groups.

CONCLUSION: General anesthesia of clinical standard depth can not effectively inhibit the pressor and tachycardiac responses caused by fiberoptic orotracheal intubation in children. As compared with DLS, FOB has no special advantages in preventing the cardiovascular stress responses to orotracheal intubation in children.