Outcomes from out-of-hospital cardiac arrest in Metropolitan Taipei: does an advanced life support service make a difference?

BACKGROUND: Out-of-hospital cardiac arrest (OHCA) is of major medical and public health significance. It also serves as a good indicator in assessing the performance of local emergency medical services system (EMS). There have been arguments for and against the benefits of advanced life support (ALS) over basic life support with defibrillator (BLS-D) for treating OHCA. AIMS OF THE STUDY: The study was conducted to characterise the outcomes of cardiac arrest victims in an Asian metropolitan city; to evaluate the impacts of ALS versus BLS-D services; and to explore the possible patient and arrest factors that may be associated with the observed differences in the outcomes between the two pre-hospital care models. MATERIALS AND METHODS: Taipei is an Asian metropolitan city with an area of 272 km(2) and a population of 2.65 million. The fire-based BLS-D EMS system was in the process of phasing in ALS capability. While there were 40 BLS-D teams in the 12 city districts, two ALS teams were set up in the central part of the city. In this prospective study, all adult non-traumatic OHCA from September 2003 to August 2004 were included. Patient, arrest, care, and outcome variables for OHCA victims were collected from prehospital run sheets, automatic defibrillators, and emergency department and hospital records. RESULTS: Among 1423 OHCA included in the analysis, 1037 (73%) received BLS-D service, and 386 (27%) received ALS services. The initial shockable rhythms and early bystander CPR were strongly associated with better survival for victims of cardiac arrests. Compared to BLS-D, ALS patients had similar age, sex, witness status, the rate of bystander CPR, and response timeliness but more patients in asystole (84% versus 72%, p=0.005). Patients treated by ALS were more likely to result in significantly higher rates of return of spontaneous circulation (29% versus 21%; OR=1.51 (95% CI 1.15-2.00); p=0.002) and survival to emergency department/intensive care unit admission (23% versus 15%; OR=1.66 (95% CI 1.22-2.24); p=0.001), but there was no difference in the rate of survival to hospital discharge (7% versus 5%; OR=1.39 (95% CI 0.84-2.23); p=0.17). The outcome difference from ALS services was more pronounced among patients in asystole and without bystander CPR. CONCLUSIONS: In this metropolitan EMS in Asia, the implementation of ALS services improved the intermediate, but not the final outcomes. Communities with larger populations and lower incidence of initial shockable rhythms than the OPALS study should also prioritise their resources in setting up and optimising systems of basic life support and early defibrillations. Further studies are warranted to configure the optimal care model for combating cardiac arrest.

A randomized trial of compression first or analyze first strategies in patients with out-of-hospital cardiac arrest: results from an Asian community.

BACKGROUND: It is still under debate whether a period of cardiopulmonary resuscitation should be performed prior to rhythm analysis for defibrillation for out of hospital cardiac arrests (OHCA). This study compared outcomes of OHCA treated by "compression first" (CF) versus "analyze first" (AF) strategies in an Asian community with low rates of shockable rhythms. METHODS: This randomized trial was conducted in Taipei City between February 2008 and December 2009. Dispatches of suspected OHCA that activated advanced life support teams were randomized into the CF and AF strategies. Patients assigned to CF strategy received 10 cycles of CPR prior to analysis by automatic external defibrillator. The primary outcome was sustained (>2 h) return of spontaneous circulation (ROSC) and secondary outcome was survival to hospital discharge. RESULTS: We included 289 cases in the final analysis after exclusion by pre-specified criteria, 141 were allocated to CF strategy and 148 to AF strategy. Baseline characteristics were similar. Thirty-seven (26.2%) of those receiving CF strategy and 49 (33.1%) of the AF strategy achieved sustained ROSC (p=0.25). In a post-hoc analysis of patients who achieved ROSC, those that received CF strategy were more likely to be discharged alive from the hospital (16/37=43.2% vs. 11/49=22.4%, p=0.02). CONCLUSION: In this study population of low rates of shockable rhythms, there was no difference in ROSC for CF or AF strategies. Considering the EMS operation situations, a period of paramedic-administered CPR for up to 10 cycles prior to rhythm analysis could be a feasible strategy in this community.