[Comparison of cardiovascular responses between orotracheal and nasotracheal intubation with the aid of GlideScope video laryngoscope].

OBJECTIVE: To compare the cardiovascular responses to orotracheal or nasotracheal intubation with the aid of GlideScope video laryngoscope (GSVL).

METHODS: Sixty patients, American Society of Anesthesiologists (ASA) physical status I, aged 16-50 years, scheduled for elective plastic surgery under general anesthesia,were randomly allocated equally to the orotracheal intubation group (OTI group) and the nasotracheal intubation group (NTI group). After the routine anesthesia induction, orotracheal and nasotracheal intubation was respectively performed with the aid of GSVL. Non-invasive blood pressure and heart rate (HR) were recorded before (baseline values) and after anesthesia induction (postinduction values), during intubation and every minute for 5 minutes after intubation. Maximum values of blood pressure and HR during the observation periods were recorded. The product of HR and systolic blood pressure [rate pressure product (RPP)] at every time point was calculated. Duration for glottis exposure and duration for successful intubation were also noted.

RESULTS: There were no significant differences between two groups in the demographic data (P>0.05). Glottis exposure time and intubation time in NTI group were significantly longer than those in OTI group [(52.2+/-13.5) seconds vs. (40.5+/-15.2) seconds, P<0.05]. After anesthesia induction, blood pressure and RPP in both groups decreased significantly compared with baseline values, but no significant change in HR was noted. Compared with their postinduction values, the blood pressure and RPP in both groups and HR in OTI group increased significantly at intubation. In OTI group,the maximum values of HR, diastolic blood pressure (DBP), mean arterial pressure (MAP), RPP exceeded their baseline values. But in NTI group,only maximal HR during the observation period was significantly higher than the baseline values. The blood pressure at every time point was not significantly different between two groups. But intubation in OTI group caused significant increases in HR and RPP compared with those in NTI group (both P<0.05).

CONCLUSION: In anesthetized adult patients, orotracheal and nasotracheal intubations with the GSVL can result in a similar pressor response, however orotracheal intubation with GSVL causes more marked cardiovascular responses than nasotracheal intubation with the aid of GSVL.