Evaluation of pre-hospital administration of adrenaline (epinephrine) by emergency medical services for patients with out of hospital cardiac arrest in Japan: controlled propensity matched retrospective cohort study

To the Editor,
We read with great interest the article by Nakahara et al. concerning the benefit of adrenaline (epinephrine) by emergency medical services (EMS).[1] However, a growing body of evidence is accumulating to demonstrate negative consequences of pre-hospital advanced care for Out-of-Hospital Cardiac Arrest (OHCA) in Japan.[2 3] They showed pre-hospital use of adrenaline and any type of advanced airway management did not provide benefits for improving neurological outcomes of patients with OHCA in Japan. Although these results may disappoint EMS, clinicians may agree reluctantly to them in Japan.
The Fire and Disaster Management Agency in Japan does not have a practical rule about termination of resuscitation (TOR) efforts in OHCA. EMS personnel are required to do cardiopulmonary resuscitation (CPR) for all patients with OHCA for whom they are called regardless of their conditions. Thus, participants of these studies accounted for a bunch of the high risk group of patients who would not have neurologically favorable outcome. Research on TOR in Japan confirmed these facts with good applicability.[4-6] If patients who would fit with TOR rules would be excluded, the results of OHCA studies including the article by Nakahara et al. might have been changed. Our major interest would not be to investigate whether to need adrenaline and any type of advanced airway for all patients with OHCA, but it would be to develop a tool to differentiate those who may need advanced life support. By choosing the study results wisely, care by EMS would be more effective and efficient.

Reference:
1. Nakahara S, Tomio J, Takahashi H, et al. Evaluation of pre-hospital administration of adrenaline (epinephrine) by emergency medical services for patients with out of hospital cardiac arrest in Japan: controlled propensity matched retrospective cohort study. Bmj 2013;347:f6829 doi: 10.1136/bmj.f6829[published Online First: Epub Date]|.
2. Hasegawa K, Hiraide A, Chang Y, et al. Association of prehospital advanced airway management with neurologic outcome and survival in patients with out-of-hospital cardiac arrest. JAMA : the journal of the American Medical Association 2013;309(3):257-66 doi: 10.1001/jama.2012.187612[published Online First: Epub Date]|.
3. Hagihara A, Hasegawa M, Abe T, et al. Prehospital epinephrine use and survival among patients with out-of-hospital cardiac arrest. JAMA : the journal of the American Medical Association 2012;307(11):1161-8 doi: 10.1001/jama.2012.294[published Online First: Epub Date]|.
4. Goto Y, Maeda T, Goto YN. Termination-of-resuscitation rule for emergency department physicians treating out-of-hospital cardiac arrest patients: an observational cohort study. Critical care 2013;17(5):R235 doi: 10.1186/cc13058[published Online First: Epub Date]|.
5. Fukuda T, Ohashi N, Matsubara T, et al. Applicability of the prehospital termination of resuscitation rule in an area dense with hospitals in Tokyo: a single-center, retrospective, observational study: Is the pre hospital TOR rule applicable in Tokyo? The American journal of emergency medicine 2013 doi: 10.1016/j.ajem.2013.10.032[published Online First: Epub Date]|.
6. Kajino K, Kitamura T, Iwami T, et al. Current termination of resuscitation (TOR) guidelines predict neurologically favorable outcome in Japan. Resuscitation 2013;84(1):54-9 doi: 10.1016/j.resuscitation.2012.05.027[published Online First: Epub Date]|.