D-Dimer level and outcome in patients after cardiopulmonary resuscitation

Background

Clinical and experimental studies have demonstrated a marked activation of blood coagulation and fibrin formation after prolonged cardiopulmonary resuscitation (CPR). Several experimental studies suggest that thrombolysis therapy acts directly on thrombi or emboli but also enhances microcirculatory reperfusion. In this retrospective study we investigated the extent of blood coagulation and fibrin formation via the plasma D-dimer level, an indicator of endogenous fibrinolytic activity, in patients who underwent inhospital and out-of-hospital cardiac arrest from nontraumatic causes.

Methods and results

Forty-five patients were included from 1 January 2004 to 31 March 2005 after CPR in the case of restoration of spontaneous circulation (ROSC). The plasma D-dimer level was measured immediately after admission to the ICU.

Results

In 38 patients (84%) cardial reasons for cardiac arrest were found. Marked activation of blood coagulation was found in all patients. After prolonged cardiopulmonary resuscitation (ROSC not within the first 30 min) patients showed significant elevated serum D-dimer level compared with patients after ROSC in the first 30 minutes (663 μg/l vs 3,328 μg/ml, P < 0.0001; normal range <0.25 μg/ml). The time period between cardiac arrest and ROSC and plasma D-dimer level correlated significantly (r = 0.8, P < 0.01) after CPR. Patients who died showed significant elevated serum D-dimer level compared with the surviving patients (1,258 ± 1,587 μg/l vs 3,164 ± 1,974 μg/l, P = 0.026 median). The plasma D-dimer level correlated significantly to the negative outcome in these patients (r = 0.55, P < 0.01).

Conclusion

Our data demonstrate a marked time-dependent activation of blood coagulation and fibrin formation after prolonged cardiac arrest and CPR in humans. These changes of the coagulation system may contribute to reperfusion disorders and possibly affect the outcome of these patients. Further studies need to show whether elevation of the D-dimer level in patients after CPR could be a prognostic marker.