A Los Angeles countywide research study examining whether magnesium sulfate can protect stroke victims' brains when administered by paramedics within two hours of stroke onset is now expanding to include patients who cannot give their immediate consent.
"Deferred consent" in research studies is used in certain medical situations -- such as cardiac arrest or severe stroke -- that occur suddenly and render the victim incapable of providing informed consent for participation. Federal regulations enacted in 1996 allow deferred consent for research in select emergency circumstances in which the therapy may directly benefit the participant.
For this research trial, the Field Administration of Stroke Therapy-Magnesium (FAST-MAG) study, patients will only be enrolled using the deferred consent process if they are accompanied by family, friends, co-workers or other individuals who know them. The research doctor will explain the study to these individuals and give them an opportunity to decline the patient's participation. All patients will be notified about the study as soon as possible after they regain full competency.
In 2003, the National Institutes of Health awarded a $16 million grant to a consortium of Los Angeles County hospitals and emergency medical services provider agencies to perform the pivotal trial, which is being conducted at up to 69 county hospitals over the next four years. To date, the trial has enrolled more than 250 of the planned 1,298 patients, who are randomized to receive magnesium sulfate or a placebo.
In experimental models, magnesium sulfate reduces stroke damage by dilating brain blood vessels and by preventing buildup of damaging calcium in injured nerve cells.
"Time is of the essence in treating acute stroke," said Dr. Jeffrey Saver, professor of neurology at the David Geffen School of Medicine at UCLA and the study's principal investigator. "By incorporating paramedics to deliver a brain-protecting agent for the first time ever in a large trial, we hope to pioneer a new, more successful era in stroke therapy."
An initial pilot study, conducted between May 2000 and January 2002, showed promising results. Paramedics in the field initiated the drug much more quickly, rather than waiting until the patient was in the hospital, as is the usual approach, and patients showed a tendency toward better recovery.
"The pilot trial showed that paramedics can recognize stroke accurately and safely start magnesium sulfate in the field," said Dr. Sidney Starkman, professor of emergency medicine and neurology at the Geffen School of Medicine and a co-principal investigator on the study. "Now we need to perform the large pivotal trial to determine definitively if early magnesium sulfate improves patient outcome."
Now that initial safety experience has been gained, the study is being expanded to include more patients with severe strokes, including those who cannot give their informed consent.
"These are the patients who are in greatest need of a beneficial stroke treatment," said Dr. Marc Eckstein, medical director of the Los Angeles Fire Department and a co-principal investigator on the study.
Stroke is the third leading cause of death and the leading cause of disability in the United States. More than 700,000 Americans suffer a stroke each year. Available treatments for stroke currently benefit fewer than one in 100 patients.
The FAST-MAG trial is being performed in conjunction with paramedics from 29 provider agencies in Los Angeles County. All medical directors of emergency medicine departments, neurologists and neurosurgeons in the county are being invited to join the trial as site investigators. A core group of 16 full-time study nurse research coordinators is available to provide paramedic and nursing education and to assist study hospitals with study implementation.
All aspects of the proposed investigation, including the consent process and public notification prior to beginning the research, must be approved by the more than 40 emergency medical service and hospital institutional review boards overseeing the study.
Any community member who does not want to be included in this study without their own informed consent can obtain a medical alert bracelet that indicates to paramedics that he or she has chosen to opt out of the study. To obtain a bracelet, call the FAST-MAG Clinical Coordinating Center at (310) 794-6160.
The investigators welcome comments regarding the study from the public. They may be submitted to firstname.lastname@example.org.