Environmental factors encountered during out-of-hospital intubation attempts

Emergency medical services (EMS) literature has studied paramedic performance with endotracheal intubation; however, there are few data describing environmental differences between out-of-hospital and in-hospital providers during intubation attempts. The purpose of this study was to describe the environmental factors encountered by paramedics.

Midwest, urban, public utility model, all-advanced life support (ALS) ambulance service with 85,000 calls and 55,000 transports per year.

Prospective, observational study using a standardized data-collection tool completed on all adult cardiac arrest patients for whom intubation was attempted during the period from September 1, 2000, through September 1, 2004. Descriptive data including count and frequency statistics of environmental factors were calculated.

There were 1,894 attempts on 1,396 patients during the study period; 236 (12.5%) attempts on 161 patients (11.5%) were removed from the analysis because of incomplete data, leaving 1,658 attempts on 1,235 patients. The intubation success rate was 85% (95% confidence interval [CI] 83, 97). Paramedics most frequently attempt intubation indoors (1,239, 75%), prefer to kneel at the patient's head (899, 54%), encounter significant scene distractions (340, 20%), have optimal lighting (1,271, 77%), but frequently have suboptimal space (655, 40%). Patients are most often supine (1,653, 99%).

The out-of-hospital intubation environment is significantly different from that of in-hospital providers. Paramedics frequently have a poor physical operating environment and encounter significant distractions while trying to perform endotracheal intubation. Future studies should analyze the association of these factors with intubation success.