Prekker, ME, Kwok H, Shin S, Carlbom D, Grabinsky MD, Rea TD (2014) The process of prehospital airway management: Challenges and solutions during paramedic endotracheal intubation. Crit Care Med42(6): 1372–8
This evaluation of pre-hospital airway management within King County, Washington linked prospective airway management registry data with Emergency Medical Service (EMS) records to review challenges and solutions associated with paramedic endotracheal intubation (ETI) in patients aged >12 years during 2006–2011.
Paramedics within this system comprise a relatively small proportion of the total EMS workforce (approximately 150), and are permitted to perform ETI autonomously in cardiac arrest and after medical consultation in non-arrest patients, incorporating drug assisted rapid sequence intubation (RSI) where required. During the study period, paramedics responded as part of a two tier system to 22% of the total EMS activations (n=120 789), with the remainder of these calls handled by basic life support resources alone.
Advanced airway management procedures were attempted in 6.2% (n=7 523) of paramedic activations. The mean ageof patients in whom ETI was attempted was 59 years, and 60% were male. Almost one-in-five (19%) did not survive to hospital admission. Indications for ETI were cardiac arrest (n=2 662, 35%), respiratory failure (n=1 329, 18%), multiple trauma (n=551, 7%), traumatic brain injury (n=446, 6%), and non-traumatic acute neurological decompensation (n=803, 11%).
‘…paramedics within King County achieved ETI success rates comparable with other highperforming EMS systems and emergency physicians’
Over three quarters of patients were intubated on the first attempt (77%), with first pass success varying from 86% in toxicological emergencies to 71% in cardiac arrest. First pass success rates were highest with grade 1 larygnoscopic view (95%) and lowest with grade 4 (31%).
RSI was used for the initial ETI attempt in over half of cases (n=4 032, 54%), with paramedics achieving a higher proportion of favourable laryngoscopic views (grade 1 and 2) in these patients versus those in whom nonpharmacologically assisted ETI was attempted (83% versus 73% respectively).
Paramedics identified a number of factors impeding ETI, including fluids obstructing laryngeal view (n=854, 50%), obesity (n=484, 28%), patient position (n=299, 17%) and facial or spinal trauma (n=101, 6%). At least one factor impeding ETI was encountered in 36% of cases with first pass success and in 72% of cases requiring two or more attempts at ETI.
In cases with an initial ETI failure (n=1 715), paramedics performed corrective actions before further ETI attempts in the majority of patients (89%). These included suctioning of the oropharynx, optimising patient position, changing operator, and deploying a bougie. The overall ETI success rate was 99% and was similar for arrest and non-arrest patients. In patients with failed ETI, surgical airway was performed in 27 cases (0.36%), with the remainder managed with bag-valvemask ventilation alone (n=60, 0.8%). During the study period, supraglottic airways were not routinely available, but these have now been provided for use as a rescue airway.
The authors conclude that paramedics within King County achieved ETI success rates comparable with other high-performing EMS systems and emergency physicians. These results must be interpreted in the context of a system where small numbers of highly trained paramedics provide advanced airway management in 6.2% of cases attended, and are required to access further anaesthetic training if they perform less than 12 intubations per annum. Adjustments made by paramedics in the event of initial ETI failure underline the importance of appropriate patient positioning and ensuring the availability of skilled assistance and a bougie prior to attempting advanced airway management.