Ethics concerns over a Hennepin Healthcare clinical trial have raised public attention to a federal rule permitting research on patients in emergency situations without their initial consent.

While little known, the rule has been commonly used in the Twin Cities for studies of everything from resuscitation equipment to breathing tubes to medications to slow bleeding at emergency scenes.

The U.S. Food and Drug Administration since 1996 has allowed “exceptions” from the usual process of gaining consent before performing experimental treatments on patients — but only in studies involving emergency treatments that couldn’t be accomplished any other way, and only if they propose to improve practices that are unproven or substandard.

The federal agency’s own guidance documents call the practice “controversial,” and require researchers to take additional steps such as alerting the community before an exception study is launched, and documenting and reacting to any community opposition before starting.

But federal leaders created the exception process because much of existing emergency medical practice hadn’t been studied, meaning that nobody knew for sure whether it was as safe or effective as it could be.

The latest Hennepin trial involved paramedics administering the anesthetic ketamine to extremely agitated patients to subdue them before they hurt themselves or others. The trial has been suspended while reviewers determine whether researchers followed exception protocols and selected appropriate patients.

Published research has found confusion in the U.S. in terms of how to solicit community input and feedback before starting exception studies.

Hennepin in Minneapolis and Regions Hospital in St. Paul both took part in a recent trial of tranexamic acid to see whether the medication would slow bleeding in patients with traumatic brain injuries. The hospitals in that instance issued public notices, but also offered to send bracelets to people in the community that they would need to wear in order to opt out of the research.

Other recent exception studies in the Twin Cities included Hennepin’s comparative trial to determine which method of intubation worked better to help patients breathe.

Regions tested devices made at the time by a Roseville-based company to improve the outcomes of CPR for cardiac arrest patients.

The University of Minnesota is currently studying whether outcomes are better for certain cardiac arrest patients if they bypass intensive care units and go directly to catheterization labs to have clots in their blood vessels removed.