While prior studies describe the clinical presentation of patients requiring paramedic out-of-hospital endotracheal intubation (ETI), limited data characterize the underlying medical conditions or comorbidities. We sought to characterize the medical conditions and comorbidities of patients receiving successful paramedic out-of-hospital ETI.
We used Pennsylvania statewide EMS clinical data, including all successful ETIs performed during 2003–2005. Using multiple imputation triple-match algorithms, we probabilistically linked EMS ETI to statewide death and hospital admission data. Each hospitalization record contained one primary and up to eight secondary diagnoses, classified according to the International Classification of Diseases, Clinical Modification, ninth edition (ICD-9-CM). We determined the proportion of patients in each major ICD-9-CM diagnostic group and subgroup. We calculated the Charlson Comorbidity Index for each patient. Using binomial proportions with confidence intervals, we analyzed the data and combined imputed results using Rubin's method.
Across the imputed sets, we linked 25,733 (77.7% linkage) successful ETI to death or hospital records; 56.3% died before and 43.7% survived to hospital admission. Of the 14,479 deaths before hospital admission, most (92.7%, 95% CI: 92.5–93.3%) presented to EMS in cardiac arrest. Of the 11,255 hospitalized patents, the leading primary diagnoses were circulatory diseases (32.0%, 30.2–33.7%), respiratory diseases (22.8%, 21.9–23.7%), and injury or poisoning (25.2%; 22.7–27.8%). Prominent primary diagnosis subgroups included: asphyxia and respiratory failure (15.2%), traumatic brain injury and skull fractures (11.3%), acute myocardial infarction and ischemic heart disease (10.9%), poisoning, drug and alcohol disorders (6.7%), dysrhythmias (6.7%), hemorrhagic and non-hemorrhagic stroke (5.9%), acute heart failure and cardiomyopathies (5.6%), pneumonia and aspiration (4.9%), and sepsis, septicemia and septic shock (3.2%). Most of the admitted ETI patients had a secondary circulatory (70.8%), respiratory (61.4%), or endocrine, nutritional or metabolic secondary diagnosis (51.4%). The mean Charlson Index score was 1.6 (95% CI: 1.5–1.7).
The majority of successful paramedic ETI occur on patients with cardiac arrest, circulatory and respiratory conditions. Injury, poisoning and other conditions compromise smaller but important portions. ETI patients have multiple comorbidities. These findings may guide the systemic planning of paramedic airway management care and education.