Prevalence of difficult airway predictors in cases of failed prehospital endotracheal intubation

Background Difficult airway predictors (DAPs) are associated with failed endotracheal intubation (ETI) in the emergency department (ED). However, little is known about the relationship between DAPs and failed prehospital ETI. Objective Our aim was to determine the prevalence of common DAPs among failed prehospital intubations. Methods We reviewed a quality-improvement database, including all cases of ETI in a single ED, over 3 years. Failed prehospital (FP) ETI was defined as a case brought to the ED after attempted prehospital ETI, but bag-valve-mask ventilation, need for a rescue airway (supraglottic device, cricothyrotomy, etc.), or esophageal intubation was discovered at the ED. Physicians performing ETI evaluated each case for the presence of DAPs, including blood/emesis, facial/neck trauma, airway edema, spinal immobilization, short neck, and tongue enlargement. Results There were a total of 1377 ED ETIs and 161 had an FP-ETI (11.8%). Prevalence of DAPs in cases with FP-ETI was obesity 13.0%, large tongue 18.0%, short neck 13%, small mandible 4.3%, cervical immobility 49.7%, blood in airway 57.8%, vomitus in airway 23.0%, airway edema 12.4%, and facial or neck trauma 32.9%. The number of cases with FP-ETI and 0, 1, 2, 3, or 4 or more DAPs per case was 22 (13.6%), 43 (26.7%), 23 (24.3%), 42 (26.1%), and 31 (19.3%), respectively. Conclusions DAPs are common in cases of FP-ETI. Some of these factors may be associated with FP-ETI. Additional study is needed to determine if DAPs can be used to identify patients that are difficult to intubate in the field.