Introduction. Heparin administration during cardiopulmonary resuscitation (CPR) may prevent activation of coagulation after successful resuscitation for out-of-hospital cardiac arrest (OHCA). We hypothesize that such an approach is not associated with an increased rate of bleeding, but it has not been evaluated. We performed a pilot randomized clinical study assessing the safety of intra-arrest heparin administration in OHCA patients with suspected acute myocardial infarction (AMI) and its impact on their prognosis.
Materials and Methods. OHCA patients were randomized during CPR to 10 000 units of intra-arrest intravenous heparin (Group H) or to treatment without heparin (Group C). The occurrence of major bleeding and the presence of a favourable neurological result 3 months after OHCA, were analyzed.
Results. Out of 88 randomized patients, AMI was subsequently confirmed in 63 of them (71.6 %). There were 30 patients in group H and 33 in group C. No major bleeding event was observed in either group. Return of spontaneous circulation (ROSC, Group H: 40.0%, Group C: 45.4%, p=0.662) and a good neurological result 3 months after OHCA (Group H: 6.7 %, Group C: 9.1 %, p=0.921) did not differ between groups.
Conclusions. Intravenous administration of 10 000 units of heparin during CPR for OHCA in patients with supposed AMI was safe. We did not find any improvement in prognosis for our sample of limited size. Though the procedure proved safe, we recommend postponing the administration of heparin until ROSC, assessment of clinical state and recording of a twelve-lead ECG.
Key words: out-of-hospital cardiac arrest, heparin, major bleeding