Intubation of prehospital patients with curved laryngoscope blade is more successful than with straight blade

Published:February 03, 2018DOI:



      Direct laryngoscopy can be performed using curved or straight blades, and providers usually choose the blade they are most comfortable with. However, curved blades are anecdotally thought of as easier to use than straight blades. We seek to compare intubation success rates of paramedics using curved versus straight blades.


      Design: retrospective chart review. Setting: hospital-based suburban ALS service with 20,000 annual calls. Subjects: prehospital patients with any direct laryngoscopy intubation attempt over almost 9 years. First attempt and overall success rates were calculated for attempts with curved and straight blades. Differences between the groups were calculated.


      2299 patients were intubated by direct laryngoscopy. 1865 had attempts with a curved blade, 367 had attempts with a straight blade, and 67 had attempts with both. Baseline characteristics were similar between groups. First attempt success was 86% with a curved blade and 73% with a straight blade: a difference of 13% (95% CI: 9–17). Overall success was 96% with a curved blade and 81% with a straight blade: a difference of 15% (95% CI: 12–18). There was an average of 1.11 intubation attempts per patient with a curved blade and 1.13 attempts per patient with a straight blade (2% difference, 95% CI: −3–7).


      Our study found a significant difference in intubation success rates between laryngoscope blade types. Curved blades had higher first attempt and overall success rates when compared to straight blades. Paramedics should consider selecting a curved blade as their tool of choice to potentially improve intubation success.


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