ABSTRACT
STUDY OBJECTIVES: To identify the hemodynamic responses to orotracheal intubation using a GlideScope videolaryngoscope (GSVL) in healthy adults, and to determine whether the GSVL could attenuate the hemodynamic response to orotracheal intubation compared with the Macintosh direct laryngoscope (MDLS). DESIGN: Randomized study. SETTING: Operating room, Plastic Surgery Hospital of the Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, People's Republic of China. PATIENTS: 57 adult, ASA physical status I patients, scheduled for elective plastic surgery during general anesthesia requiring orotracheal intubation. INTERVENTIONS: Patients were randomly allocated to either the GSVL group (n = 30) or the MDLS group (n = 27). Anesthesia was induced with intravenous injection of fentanyl 2 microg/kg, propofol 2 mg/kg, and vecuronium 0.1 mg/kg. Orotracheal intubation was started two minutes after vecuronium injection. All intubation procedures were performed by a single anesthesiologist experienced in using an MDLS and a GSVL. After intubation, anesthesia was maintained with 1% isoflurane and 60% nitrous oxide in oxygen. MEASUREMENTS AND MAIN RESULTS: Noninvasive blood pressure (BP) and heart rate (HR) were recorded before (baseline values) and immediately after induction (postinduction values), at intubation, and for 5 minutes at one-minute intervals. Maximal BP and HR values during the observation and intubation times were also noted. The product of HR and systolic BP (ie, the rate-pressure product [RPP]) was calculated. Intubation time was significantly longer in the GSVL group than in the MDLS group (P < 0.01). Except for maximal value of diastolic BP in the GSVL group, increases in BPs during the observation in the two groups did not significantly exceed baseline values (P > 0.05). In the GSVL group, HR and RPP at intubation were significantly higher than their baseline values, and HR increases lasted for 4 minutes. In the MDLS group, HR at intubation was also significantly higher than its baseline value, but the tachycardic response lasted only for 1 minute. During the observation, there were no significant differences between the two groups in BPs, HRs, or RPPs at any time points or in their maximal values. CONCLUSIONS: The hemodynamic responses to orotracheal intubation using a GSVL and an MDLS were similar. The GSVL had no any special advantage over the MDLS in attenuating the hemodynamic responses to orotracheal intubation.