Study challenges standard airway management during cardiac arrestsBMJ 2013; 346 doi: http://dx.doi.org/10.1136/bmj.f253 (Published 16 January 2013) Cite this as: BMJ 2013;346:f253
Clearing and maintaining an airway is one of the first priorities for emergency personnel called to an out of hospital cardiac arrest, and many are trained to intubate or place supraglottic devices such as a laryngeal mask airway. Evidence has begun to emerge that these advanced techniques may do more harm than good in the prehospital setting. The latest study comes from Japan, where a national register recorded more the 600 000 out of hospital arrests between 2005 and 2010. The odds of a good neurological outcome were 62% lower for adults managed with an endotracheal tube or a supraglottic airway than for comparable adults managed with a bag and mask (1.1% v 2.9%; odds ratio 0.38, 95% 0.37 to 0.4). Intubation and supraglottic airways were both implicated in poor outcomes in a series of extensively adjusted observational analyses. Six per cent of the cohort (41 972) were intubated, and just over one third were managed with a supraglottic airway (37%; 239 550/649 359).
The new findings look secure and compelling, says a linked editorial (p 285). Adults managed with advanced airway techniques clearly do worse than others and a direct effect is plausible. Placing an airway might interrupt chest compressions, tubes can be placed wrongly or dislodge on the move, and overenthusiastic ventilation can reduce coronary and cerebral perfusion. The other possibility is that people managed this way have a poorer prognosis to start with because of unmeasured factors that can’t be accounted for even in sophisticated statistical models. Prospective randomised trials are the only way to find out.
Cite this as: BMJ 2013;346:f253