Background: Rates of ventilator-associated pneumonia (VAP) are highest among patients intubated on an emergency basis following trauma. We reported previously a retrospective analysis demonstrating an association between subjective aspiration and VAP after pre-hospital intubation. We hypothesize that by directing paramedics to note features of aspiration at intubation, we will confirm prospectively the association between pre-hospital aspiration and subsequent pneumonia in trauma patients.
Methods: Paramedics collected data regarding aspiration at the time of intubation. All intubated patients admitted to a level 1 trauma center intensive care unit (ICU) were included. Data comprised a clinical impression of pre-hospital aspiration, as well as the presence and timing of blood and emesis in the airway. Injury severity, co-morbidities, and outcomes were collected from the trauma registry. Healthcare-associated pneumonia (HAP) was identified by medical record review of both bronchoalveolar lavage culture results and discharge diagnosis. Descriptive statistics and univariate analysis of outcomes by aspiration status, as well as covariable adjustment using propensity scores, were performed.
Results: Of the 228 patients, 89 (39%) were determined by paramedics to have aspirated. The majority of those who aspirated (84 [94%]) did so prior to intubation. Patients who aspirated had higher Injury Severity Scores than those who did not aspirate (25.0 ± 1.7 vs. 21.9 ± 1.5 points; p=0.04) and lower preintubation Glasgow Coma Scale scores (8.2 ± 0.50 vs. 9.6 ± 0.40; p=0.02). Of the 89 patients who aspirated around the time of intubation, 14 (16%) developed HAP vs. five (3.6%) of those who did not aspirate (p<0.01). We observed non-significant increases in mortality rate, ICU length of stay (LOS) and duration of mechanical ventilation after aspiration (deaths: 21 [23.6%] vs. 23 [16.6%]; p=0.19; ICU LOS: 5.3 ± 0.9 vs. 4.1 ± 0.5 days; p=0.13; duration of mechanical ventilation: 5.3 ± 1.2 vs. 3.2 ± 0.5 days; p=0.10).
Conclusions: Aspiration prior to intubation was reported commonly by paramedics and was associated with a higher risk of HAP.