P ATIENT S TATUS AND T IME TO I NTUBATION IN THE A SSESSMENT OF P REHOSPITAL I NTUBATION P ERFORMANCE

Abstract

Assessment of paramedic endotracheal intubation (ETI) performance often does not account for varied clinical conditions or the time required to complete the procedure. Objective. To demonstrate the utility of patient status and time to intubation (TTI) for evaluating prehospital ETI performance. Methods. Paramedic charts were reviewed for the period January-December 1998. Patient clinical status was defined as cardiac arrest (absence of perfusing rhythm) or non-cardiac arrest (presence of perfusing rhythm). Method, route, and success of ETI were noted. The TTI was determined as the elapsed time from on-scene arrival to securing of the endotracheal tube. Time elapsed from on-scene arrival to emergency department arrival was noted for instances of failed ETI. Statistical analysis was performed using chi-square and survival analysis (Kaplan-Meier estimator). Results. Computer records were available for 26,026 patient contacts. Of 893 documented ETI attempts, 771 (86%) were successful. The ETI success rate was significantly higher (p < 0.001) for cardiac arrests (551 of 591, 93.2%) than for non-cardiac arrests (220 of 302, 72.9%). Median TTIs were 5 minutes (95% CI: 5, 5) for cardiac arrests and 17 minutes (95% CI: 14, 20) for non-cardiac arrests; this difference was significant (p < 0.001). For non-cardiac arrests, ETI success was significantly (p = 0.002) higher for orotracheal intubation (OTI) (168 of 214, 78.5%) than for nasotracheal intubation (NTI) (52 of 88, 59.1%). Median TTIs were 15 minutes (95% CI: 13, 17) for OTI and 25 minutes (95% CI: 23, 27) for NTI; this difference was significant (p = 0.002). For non-cardiac arrests, the difference in ETI success rates between conventional ETI (63 of 88, 71.6%) and midazolam-facilitated ETI (157 of 214, 73.4%) was not significant (p = 0.75). Median TTIs were 16 minutes (95% CI: 13, 19) for conventional ETI and 19 minutes (95% CI: 16, 22) for the midazolam-facilitated ETI; this difference was not significant (p = 0.08). Conclusions. The TTI is shorter and ETI success rates are higher for patients in cardiac arrest. Similar trends are observed for OTI compared with NTI in non-cardiac arrest patients. Success rates and TTIs for conventional vs midazolam-facilitated intubation in non-cardiac arrest patients do not differ. Prehospital ETI data should be segregated according to patient clinical status. Survival analysis of TTI can be used to establish time benchmarks for performing field intubation and to define strategies for approaching field intubation.