Impact of initial intervention on long-term neurological recovey after cardiac arrest: data from the Luxembourg "North Pole" cohort.

Background: Prognosis after cardiac arrest is variable and difficult to predict. Early prognostic markers would facilitate the care of these patients.

Aims: Therefore, we evaluated the impact of initial interventions after resuscitation on neurological outcome at 6 months.

Material and methods: We conducted a retrospective analysis of the patient charts from consecutive cardiac arrest patients admitted to our intensive care unit and treated with induced hypothermia.

Results: Over a 3-year period, 90 patients were included in our study. Sixty-four percent of the patients had bystander cardio-pulmonary resuscitation. An automated external defibrillator (AED) was used in 19% of the patients and the mean time to first defibrillation was 11 +/- 8.9 minutes. Patients being resuscitated and defibrillated by bystanders did better than those who had CPR only and far better than those patients in whom no rescue measures where attempted at all (73% vs. 56% vs. 32% for good neurological outcome, respectively, p= 0.03). Witnessed cardiac arrest was more frequent in patients with a good outcome than in those who collapsed without a witness (91% vs 75%, p = 0.03). In 76% of the patients with good outcome, CPR was performed whereas only 52% benefited from these measures in the bad outcome group (p = 0.01). Although the use of an AED was not significantly different between good and bad outcome groups (26% vs. 11%, p = 0.06), time to first defibrillation was significantly lower in patients with good outcome (8.7 +/- 6.3 vs. 13.3 +/- 11.3 minutes, p = 0.05). In the 17 patients in whom an AED was used, 12 (71%) recovered without major sequelae whereas in the 73 cases where no AED was used, only 34 (47%) had a good outcome (p = 0.06). At 6 months follow-up, 46 (51%) survivors had a good outcome (cerebral performance category 1-2), 5 (6%) survived with severe neurological sequelae or stayed in coma and 39 (43%) died.

Conclusions: Our local data confirm that early interventions have a major impact on survival of cardiac arrest patients. Efforts should concentrate on delivering rapid and high quality CPR as well as early defibrillation by AED's to every patient in cardiac arrest. Besides large scale Basic life support training, the introduction of dispatcher assisted CPR and the implementation and use of public AED's could considerably help to improve outcome in these patients.