Pulled from the twisted metal of a car accident, someone with a blunt brain injury or a stopped heart could find themselves unknowingly participating in a clinical trial. Is that ethical?

Yes, say researchers, who are testing new emergency treatments on accident victims across the US and Canada.

Doctors are not privileged to do research without consent. George Annas, Boston University

In early June, emergency workers in the Toronto area were the first to begin comparing treatments for cardiac arrest. The study is one of three emergency trials evaluating the best interventions for those aged 15 or older with traumatic shock or brain injury and those over 17 whose hearts have stopped.

The trials will take place at more than 250 sites in North America. But here's the catch: because the participants are in emergency situations, they cannot give informed consent—a cornerstone of most clinical trials.

“You have to do something within the first 30 seconds to two minutes,” says the University of Toronto's Arthur Slutsky, principal investigator for the Toronto unit. “How is it possible to get informed consent in that short period of time?”

Regulators, ethicists and, increasingly, the public scrutinize trials that don't ask for consent. Researchers argue that the trials are essential to identifying the best interventions for medical emergencies. But some ethicists chafe at any research done without informed consent.

“Doctors are privileged to treat in emergencies without consent,” says Boston University bioethicist George Annas. “They are not privileged to do research without consent.”

About 175,000 injury-related deaths occur in North America each year. Cardiac statistics are equally grim. Of the 180,000 North Americans experiencing out-of-hospital cardiac arrest, nearly 95% die before arriving at a hospital.

The network of ten research centers in the US and Canada expects to enroll nearly 15,000 individuals in the cardiac trial, evaluating the effectiveness of cardiopulmonary resuscitation given with or without a small, plastic valve. The valve prevents air from reentering the chest during chest compressions, creating a vacuum in the chest cavity and increasing blood flow to the heart.

Two other trials, involving up to 4,000 individuals each, started about a year ago, testing hypertonic saline, a concentrated salt solution, alone or in combination with the sugar dextran as a resuscitative fluid for traumatic shock or severe brain injury. Saline is normally administered at the same concentration as that in blood.

Numerous institutional review boards and funding and regulatory agencies, including the US National Institutes of Health and the US Food and Drug Administration (FDA), approved the research protocols. The protocols legitimately bypass informed consent under a 1996 FDA exception and a 1998 Canadian consent waiver.

Under the FDA rule, scientists must get public feedback before the trial begins. The researchers followed those guidelines, conducting town hall meetings and telephone surveys. They also excluded communities from which public feedback was overwhelmingly negative.

In some cases, institutions provide opt-out mechanisms, such as alert bracelets, though the FDA does not require them (Nat. Med. 13, 652, 2007). In these trials, conscious individuals can refuse experimental treatment although, in those circumstances, many are unconscious.

The researchers say their trials are ethical because doctors disagree about the most effective treatments for these conditions. The trials, Slutsky notes, will contribute valuable data to settle some of those debates.

Even those opposing research without consent have proposed few alternative models for emergency research. Some suggest modifying the rules to better gauge the public's awareness of the trials. For example, Annas says researchers should be required to secure community approval, measured by a public vote or survey, rather than merely showing that they have consulted the community.

Public consultation can be tricky with large trials, which have to balance each community's concerns with maintaining a consistent protocol at different trial sites, notes Wake Forest University bioethicist Nancy King.

King advocates getting prior consent whenever possible, perhaps enrolling at-risk populations ahead of time. “I think we have to think more creatively abut seeking and gaining consent,” she says.

Nevertheless, even critics say that approach is impractical for accidents or other trauma. “Nobody's going to sign up ahead of time on the possibility that you might be in an automobile accident or have a heart attack,” Annas says.