New results about early therapeutic hypothermia in sudden cardiac death and following return of spontaneous circulation

Introduction

Therapeutic hypothermia is defined as controlled cooling of body temperature for therapeutic purposes. At present, the use of mild-moderate hypothermia (32 to 34°C) in patients with neurological damage is increasing in the ICU. In this regard, recent studies suggest that it is able to improve the neurological outcome in patients with anoxic cerebral damage following sudden cardiac death (SCA) [1]. The aim of this study is to assess the role of therapeutic hypothermia on neurological outcome in patients who experienced SCA with ensuing return of spontaneous circulation (ROSC).

Methods

Ninety adult patients, aged between 18 and 85, referred to our ICU after SCA due to cardiac disease with following ROSC were randomly allocated to the following treatment groups: patients in group 1 were treated immediately after admission with therapeutic hypothermia plus standard treatment, patients in group 2 received only standard treatment. All patients at entry presented with GCS 3. Neurological outcome was assessed on discharge and after 6 months, by means of GOS scale (0 = dead, 1 = vegetative, 2 = severely disabled, 3 = moderately disabled, 4 = good recovery). We consider scores 0 to 1 as unfavourable outcome, scores from 2 to 4 as favourable outcome. To compare the two groups we used the Mann-Whitney U test of for continuous variables, the chi-square test for qualitative variables.

Results

Patients in group 1 (45 patients) and in group 2 (45 patients) resulted statistically comparable for sex (P = 0.14) and age (P = 0.68) and presentation ECG rhythm (P = 0.42) and APACHE II score (P = 0.34). At discharge from the ICU, 66.6% of patients in group 1 presented favourable neurological outcome (GOS 2 to 4) versus 35% of patients in group 2. At 6 months, 70% of patients in group 1 presented favourable neurological outcome (GOS 2 to 4) versus 38.3% of patients in group 2. The mortality was 16.6% in group 1 versus 36.6% in group 2 (P = 0.003). The patients who improved their GOS values were 64% in group 1 and 18% in group 2 (P < 0.005).

Conclusions

Our study demonstrated that early treatment with therapeutic hypothermia in the patient who had SCA improves neurological outcome. It is independent of the rhythm of presentation. Besides, we reached statistical significance.