What is the likely outcome when using video laryngoscopy compared to direct laryngoscopy for intubation in a patient with obesity after a polysubstance overdose?

Video Laryngoscopy vs Direct Laryngoscopy in Obese Patients Requiring Emergency Intubation

Video laryngoscopy is associated with higher first-pass intubation success compared to direct laryngoscopy in patients with obesity, without significantly increasing procedure time or complications. 1

First-Pass Success Rate

Video laryngoscopy significantly increases the likelihood of successful first-attempt intubation in obese patients. The most recent meta-analysis specifically examining patients with obesity found videolaryngoscopy achieved a pooled risk ratio of 0.42 (95% CI 0.22-0.78, p=0.0064) for first-pass success compared to direct laryngoscopy 1. This translates to approximately double the odds of success on the first attempt when controlling for difficult airway predictors (OR 3.07,95% CI 2.19-4.30) 2.

Supporting Evidence Across Settings

• In scheduled surgery with predicted difficult airways: Videolaryngoscopes improve glottic visualization and increase first-attempt success rates compared to Macintosh blade laryngoscopy 3
• In emergency departments: First-attempt success with direct laryngoscopy was 68% versus 78% with videolaryngoscopy (p=0.001), with adjusted odds of success OR 2.20 (95% CI 1.51-3.19) 2
• In ICU settings: Videolaryngoscopy increased first-attempt success from 55% to 79% and decreased Cormack & Lehane grades III-IV from 20% to 7% 3

Intubation Time

There is no significant difference in time to intubation between videolaryngoscopy and direct laryngoscopy (SMD 0.13,95% CI -0.26 to 0.52, p=0.51), though this finding has low certainty due to high heterogeneity 1. In obese patients specifically, mean time difference was only -1.7 seconds (95% CI: -6.9 to 3.5 seconds) 4.

Complications and Safety Profile

Videolaryngoscopy demonstrates a favorable safety profile with reduced trauma:

• Fewer laryngeal/airway traumas: OR 0.68 (95% CI 0.48-0.96) 5
• Reduced postoperative hoarseness: OR 0.57 (95% CI 0.36-0.88) 5
• No significant difference in sore throat at PACU (OR 1.00,95% CI 0.73-1.38) or 24 hours postoperatively (OR 0.54,95% CI 0.27-1.07) 5
• Reduced esophageal intubation: OR 0.14 (95% CI 0.02-0.81, p=0.03) 3

Hypoxia and Mortality

Current evidence shows no significant difference in hypoxia (OR 0.39,95% CI 0.10-1.44) 5 or mortality (OR 1.09,95% CI 0.65-1.82) 5 between videolaryngoscopy and direct laryngoscopy, though these outcomes are graded as very low quality due to limited data.

Clinical Context for Obese Emergency Patients

Obesity creates specific intubation challenges that favor videolaryngoscopy:

• Obese patients have altered airway anatomy and reduced physiological reserve, increasing complication risk 1
• Oxygen desaturation develops rapidly during prolonged intubation attempts in obese patients 4
• Male gender, BMI >50, and neck circumference ≥42 cm increase risk of difficult mask ventilation and intubation 3
• The presence of obesity as a difficult airway predictor specifically increases odds of videolaryngoscopy success over direct laryngoscopy 2

Guideline Recommendations for This Scenario

For emergency intubation in obese patients, videolaryngoscopy should be considered first-line:

• Guidelines recommend using videolaryngoscopes first in patients with at least two criteria for difficult intubation when mask ventilation is possible (Grade 1+) 3
• Videolaryngoscopy is recommended as a second-attempt device if Cormack-Lehane grade III or IV is encountered with direct laryngoscopy (Grade 2+) 3
• In ICU settings with predicted difficulty (MACOCHA score ≥3), videolaryngoscopy is preferred as first-line management 3

Critical Pitfalls to Avoid

Potential trauma with stylet use: Videolaryngoscopy may be associated with upper airway or laryngeal trauma particularly when a stylet is used during the procedure 3. Exercise caution when advancing the endotracheal tube.

Operator experience matters: The performance of videolaryngoscopes depends on device type, operator expertise, and patient characteristics 3. Ensure adequate training and familiarity with the specific device.

Have backup plan ready: Despite improved success rates, failed intubation can still occur. Ensure immediate availability of supraglottic airway devices and surgical airway equipment 3.

Answer to Question

Higher first-pass success is the most likely outcome when using videolaryngoscopy compared to direct laryngoscopy in this obese patient requiring emergency intubation after polysubstance overdose 1, 2.