Preliminary experience with a prospective, multi-centered evaluation of out-of-hospital endotracheal intubation

Previous out-of-hospital airway management data are limited by small, single-site designs. We sought to evaluate the feasibility of performing a prospective, multi-centered evaluation of out-of-hospital endotracheal intubation (ETI) using a standardized data collection tool.

We designed a prospective multi-centered observational study involving 45 advanced life support (ALS) services from a mid-Atlantic state. Using a standardized data form, prehospital personnel reported details of each attempted ETI, including patient demographics, methods used, difficulties encountered, and initial patient outcomes. We calculated and assessed data form return rates (using independent queries of the number of ETI attempted by each EMS service) and missing data entry rates. We also performed preliminary cross-sectional assessments of factors of current interest in out-of-hospital ETI. Accuracy and validity of responses were not evaluated. Data were stored centrally and analyzed using descriptive techniques.

Participants included 8 urban, 15 suburban, 20 rural, and 2 air medical services. Data forms were received on 783 adults receiving ETI attempts during the study period June 1, 2001-November 30, 2001. The pooled data form return rate was 72.7%. Per-service return rates ranged from 0 to 100% and the median per-service return rate was 75%. Non-response (data form not returned for attempted intubation) was problematic, with nine services demonstrating data return rates less than 50%. Data return rates could not be calculated for an additional nine services. The missing data entry rate was 0.5-22.2%. The overall reported ETI success rate was 86.8% (92.8% for cardiac arrests and 76.8% for non-arrests) and did not appear to vary between population settings. There were two cases of delayed recognition of esophageal intubation, one case of unrecognized esophageal intubation, and 22 cases of tube dislodgement during patient care or transport. Bag-valve-mask ventilation was used as the rescue airway technique in the majority of failed ETI. When stratified for cardiac arrests vs. non-arrests, ETI success was not associated with field or initial ED survival.

We successfully obtained complete data for the majority of ETI attempted across multiple EMS services. Our data also indicate the need to address problems with non-response. Preliminary cross-sectional data highlight areas of current interest in out-of-hospital airway management.