Performance characteristics and complications of an Inter-Changeable Operator Model for intubation in an Australian helicopter emergency medical service

Abstract

Objective: The Inter-Changeable Operator Model (ICOM) enables paramedics and flight nurses to perform intubations interchangeably with team physicians in prehospital critical care. However, literature on ICOM characteristics and performance is limited. Methods: We conducted a retrospective, observational study of an ICOM operating within an Australian Helicopter Emergency Medical Service over a nine-year period. First pass success, major complication rates and clinically important time intervals were compared between first intubator groups. Results: A total of 413 patients met the inclusion criteria, with paramedics performing the majority of first intubation attempts (379/413, 91.8%). Physicians primarily conducted second intubation attempts and managed high-risk patients. In unadjusted analysis, the risk of major complication in the paramedic/supervised registrar group was not lower than the most senior physician intubator group (relative risk [RR] 0.59, 95% confidence interval [CI]: 0.26–1.32; P = 0.198) and after adjustment the risk was also not lower (RR 0.60, 95% CI: 0.24–1.54; P = 0.289). First pass failure occurred in 12 (3.1%) and 1 (4.8%) patients intubated by paramedic/supervised registrar and most senior physician groups, respectively (P = 0.498). The median (95% CI) adjusted difference in contact to intubation time between paramedic/supervised registrar first intubator and most senior physician groups was −2 min (−7 to 3; P = 0.392). Total adjusted scene time was also not significantly different between groups (median difference 2 min, 95% CI: −3 to 7; P = 0.500). Conclusions: Paramedics conducting most intubations within an ICOM are both safe and efficient. Larger studies are required to examine differences between physician subgroups.