The majority of adults surveyed indicated they would want administration of clot-dissolving medications if incapacitated by a stroke, a finding that supports clinicians' use of this treatment if patient surrogates are not available to provide consent, according to a study in the April 23/30 issue of JAMA, a neurology theme issue.

"In life-threatening emergencies involving incapacitated patients without surrogates, clinicians may intervene without obtaining informed consent, applying the presumption that reasonable people would consent to treatment in such circumstances. Whether this rationale applies to the treatment of acute ischemic stroke with intravenous thrombolysis [administration of clot-busting agent] is controversial because this intervention improves functional outcomes but is not life preserving. Nonetheless, the presumption of consent to thrombolysis for ischemic stroke has recently been endorsed by professional societies," according to background information in the study.

Winston Chiong, M.D., Ph.D., of the University of California, San Francisco, and colleagues examined presumption of consent by comparing preferences for treatment of acute ischemic stroke with thrombolysis and treatment of sudden cardiac arrest with cardiopulmonary resuscitation (CPR; in which the presumption of consent is generally accepted) in a nationally representative sample of U.S. adults 50 years of age or older. The participants were randomly assigned to read 1 of 2 scenarios: in one they experienced a severe acute ischemic stroke and were brought to a hospital, and in the other they experienced an out-of-hospital cardiac arrest and were attended to by paramedics.

The stroke scenario included a graphical depiction of potential risks and benefits of treatment with thrombolysis. The cardiac arrest scenario included a similar depiction of potential outcomes after paramedic-initiated CPR. All participants were then asked whether they would want the treatment described.

The researchers found that 76.2 percent of older adults (419 of 545 participants) wanted thrombolysis for acute ischemic stroke and 75.9 percent of older adults (422 of 555 participants) wanted CPR for sudden cardiac arrest. Female sex, divorced marital status, and lower educational attainment predicted refusal of thrombolysis; poorer physical health, previous stroke, and possession of a health care advance directive predicted refusal of CPR.

"When an incapacitated older patient's treatment preferences are unknown and surrogate decision makers are unavailable, there are equally strong empirical grounds for presuming individual consent to thrombolysis for stroke as for presuming individual consent to CPR. Because the presumption of consent is generally accepted for CPR, this finding provides empirical support for policy positions recently taken by professional societies that favor the use of thrombolysis for stroke in emergency circumstances under a presumption of consent," the authors write.