Mild therapeutic hypothermia after cardiac arrest and the risk of bleeding in patients with acute myocardial infarction

Background: The aim of the study was to report the impact of our hypothermia protocol on survival and neurological outcome. Furthermore, we were interested in the risk of bleeding complications in patients with acute myocardial infarction (AMI) being treated with percutaneous coronary revascularisation (PCI) and therapeutic hypothermia. Methods and results: In a prospective observational study we identified 31 comatose patients (25 male, age 65 +/- 13 years) admitted to our intensive care unit with out-of-hospital cardiac arrest due to AMI who were treated with hypothermia. They were compared to 31 historical age- and gender-matched controls (25 male, age 65 +/- 12 years) admitted after out-of-hospital cardiac arrest due to AMI in the era prior to hypothermia treatment. Peak creatinine kinase-MB was 118 U/L (94-248) in the hypothermia group and 131 U/L (98-257) in controls (p=0.51). In the hypothermia group, 19 patients were discharged with a favourable neurological outcome, whereas in controls, such outcome was observed in only six patients (p=0.002). In both groups, haemoglobin values and platelet counts declined during the first 48 h (all p < 0.001). No differences regarding bleeding complications (p=1.0), transfusion requirements (p=1.0), and the number of transfusions (p=0.9) were observed between the groups. Conclusions: A major improvement in neurological outcome was observed in patients treated with hypothermia. Our results indicate that the combination of reperfusion strategies and the application of hypothermia do not carry an excessive risk of bleeding complications. Patients with AMI and out-of-hospital cardiac arrest should receive the optimal therapy for both conditions, that is, either thrombolysis or PCI and therapeutic hypothermia. (C) 2007 Elsevier Ireland Ltd. All rights reserved.