Tissue plasminogen activator in cardiac arrest with pulseless electrical activity.
BACKGROUND
Coronary thrombosis and pulmonary thromboembolism are common causes of cardiac arrest. We assessed whether the administration of tissue plasminogen activator (t-PA) during cardiopulmonary resuscitation would benefit patients with cardiac arrest and pulseless electrical activity of unknown or presumed cardiovascular cause.


METHODS
Patients who were older than 16 years of age and who had more than one minute of pulseless electrical activity that was unresponsive to initial therapy outside the hospital or in the emergency department were eligible. Patients were randomly assigned to receive 100 mg of t-PA or placebo intravenously over a 15-minute period in a double-blind fashion. Standard resuscitation was then continued for at least 15 minutes. The primary outcome was survival to hospital discharge.


RESULTS
During the study period, 1583 patients with cardiac arrest were treated and 233 patients were enrolled (117 in the t-PA group and 116 in the placebo group). The characteristics of the patients in the two groups were similar. One patient in the t-PA group survived to hospital discharge, as compared with none in the placebo group (absolute difference between groups, 0.9; 95 percent confidence interval, -2.6 to 4.8; P=0.99). The proportion of patients with return of spontaneous circulation was 21.4 percent in the t-PA group and 23.3 percent in the placebo group (absolute difference between groups, -1.9; 95 percent confidence interval, -12.6 to 8.8; P=0.85).


CONCLUSIONS
We found no evidence of a beneficial effect of fibrinolysis in patients with cardiac arrest and pulseless electrical activity of unknown or presumed cardiovascular cause. Our study had limited statistical power, and it remains unknown whether there is a small treatment effect or whether selected subgroups may benefit.
Abu-Laban
Riyad B
RB
Division of Emergency Medicine, University of British Columbia, Vancouver, Canada. abulaban@interchange.ubc.ca
Christenson
James M
JM
Innes
Grant D
GD
van Beek
Catherina A
CA
Wanger
Karen P
KP
McKnight
R Douglas
RD
MacPhail
Iain A
IA
Puskaric
Joe
J
Sadowski
Richard P
RP
Singer
Joel
J
Schechter
Martin T
MT
Wood
Victor M
VM
D016887:Cardiopulmonary Resuscitation; D004311:Double-Blind Method; D004594:Electrophysiology; D004632:Emergency Medical Services; D005343:Fibrinolytic Agents / Q000627:therapeutic use*; D006323:Heart Arrest / Q000188:drug therapy* / Q000401:mortality / Q000503:physiopathology / Q000628:therapy; D006801:Humans; D011674:Pulse; D010959:Tissue Plasminogen Activator / Q000627:therapeutic use*; D017211:Treatment Failure
D005343:Fibrinolytic Agents; D010959:Tissue Plasminogen Activator