Clinical adverse events in prehospital patients with ST-elevation myocardial infarction transported to a percutaneous coronary intervention centre by basic life support paramedics in a rural region.

Abstract

It remains unclear whether ST-elevation myocardial infarction (STEMI) patients transported by ambulance over long distances are at risk for clinical adverse events. We sought to determine the frequency of clinical adverse events in a rural population of STEMI patients and to evaluate the impact of transport time on the occurrence of these events in the presence of basic life support paramedics. We performed a health records review of 880 consecutive STEMI patients transported to a percutaneous coronary intervention centre. Patients had continuous electrocardiogram and vital sign monitoring during transport. A classification of clinically important and minor adverse events was established based on a literature search and expert consensus. A multivariate ordinal logistic regression model was used to study the association between transport time (0-14, 15-29, ≥30 minutes) and the occurrence of overall clinical adverse events. Clinically important and minor events were experienced by 18.5% and 12.2% of STEMI patients, respectively. The most frequent clinically important events observed were severe hypotension (6.1%) and ventricular tachycardia/ventricular fibrillation (5.1%). Transport time was not associated with a higher risk of experiencing clinical adverse events (p=0.19), but advanced age was associated with adverse events (p=0.03). No deaths were recorded during prehospital transport. In our study of rural STEMI patients, clinical adverse events were common (30.7%). However, transport time was not associated with the occurrence of adverse clinical events in these patients.