Objectives: Cricothyrotomy is an intervention performed to salvage "can't intubate, can't ventilate" situations. Studies have shown poor accuracy with landmarking the cricothyroid membrane, particularly in female patients by surgeons and anesthesiologists. This study examines the perceived versus actual success rate of landmarking the cricothyroid membrane by resident and staff emergency physicians using obese and non-obese models.
Methods: Five male and female volunteers were models. Each model was placed supine, and a point-of-care ultrasound expert landmarked the borders of each cricothyroid membrane; 20 residents and 15 staff emergency physicians were given one attempt to landmark five models. Overall accuracy and accuracy stratified by sex and obesity status were calculated.
Results: Overall landmarking accuracy amongst all participants was 58% (SD 18%). A difference in accuracy was found for obese males (88%) versus obese females (40%) (difference = 48%, 95% CI = 30-65%, p < 0.0001), and non-obese males (77%) versus non-obese females (46%) (difference = 31%, 95% CI = 12-51%, p = 0.004). There was no association between perceived difficulty and success (correlation = 0.07, 95% CI = -0.081-0.214, p = 0.37). Confidence levels overall were higher amongst staff physicians (3.0) than residents (2.7) (difference = 0.3, 95% CI = 0.1-0.6, p = 0.02), but there was no correlation between confidence in an attempt and its success (p = 0.33).
Conclusion: We found that physicians demonstrate significantly lower accuracy when landmarking cricothyroid membranes of females. Emergency physicians were unable to predict their own accuracy while landmarking, which can potentially lead to increased failed attempts and a longer time to secure the airway. Improved training techniques may reduce failed attempts and improve the time to secure the airway.
Keywords: Emergency medicine; cricothyroid; education; residents.