When Should Resuscitation Attempts Cease?

Investigators have devised a simple clinical prediction rule to help emergency medical services (EMS) workers know when to end pointless resuscitation efforts.

Researchers at the University of Toronto (Ontario, Canada) and at Owen Sound Hospital (Ontario, Canada) analyzed data from 1,240 adult patients treated by 24 emergency medical systems in the province of Ontario from January 1, 2002, to January 30, 2004. According to the study, called the termination of resuscitation (TOR) trial, implementation of a clinical prediction rule based on three simple factors would reduce futile resuscitation efforts by almost 63%. The predictive rule they examined recommended termination of automated external defibrillator and basic life support efforts when there was no return of spontaneous circulation, no shocks were administered, and the arrest was not witnessed by EMS personnel. The mean age of patients was 69.2 years and 69% were men. Cardiac arrest was witnessed in 57.4% of cases, although EMS personnel witnessed less than 10% of cases.

Using the predictive rule, 776 patients were recommended for termination, of which four survived (0.05%), which was significantly lower than the threshold of 1% that has been suggested as reflective of medical futility. Three of the four patients survived with good cerebral performance and one had severe cerebral disability. The prediction rule recommended transport and continued resuscitation for 464 patients, of whom 37 survived, resulting in a negative predictive value of 8%. The study was published in the August 3, 2006, issue of the New England Journal of Medicine.

"The prediction rule had a positive predictive value of 99.5% [for death] and a specificity of 90.2% [for death],” wrote lead author Laurie J. Morrison, M.D., of the University of Toronto.

A potential weakness of the study, noted Gordon A. Ewy, M.D., of the University of Arizona (Tucson, USA) in an accompanying editorial, was the fact that the EMS personnel followed CPR guidelines issued by the American Heart Association (AHA) in 2000, which means that only about half of needed chest compressions were performed, thus perfusing the heart and brain only half the time. The AHA issued new CPR and cardiovascular care guidelines in 2005 recommending about twice as many chest compressions.



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University of Toronto
Owen Sound Hospital