A recent clinical trial, published in the New England Journal of Medicine and co-authored by Wayne State University School of Medicine Professor of Pediatrics and Children's Hospital of Michigan, Detroit Medical Center, Chief of Critical Care Kathleen Meert, M.D., shows that "therapeutic hypothermia" is no more effective than maintaining normal body temperature in children who have suffered cardiac arrest before being hospitalized.
Although body-cooling has long been a standard of care in treating adults after heart attacks, the recently published multi-center study has concluded that the same procedure - known as "therapeutic hypothermia" - does not confer any survival-with-quality-of-life benefit for children resuscitated after suffering out-of-hospital cardiac arrest. The study noted hypothermia is no more effective than maintaining normal body temperature by preventing fever in the children being treated.
The study, published April 25 in the New England Journal of Medicine, has major implications for critical care pediatricians.
"What this study tells us is that there's no significant advantage to using a lower-than- normal (body) temperature when caring for children who've experienced cardiac arrest," said Dr. Meert, a 1984 graduate of the School of Medicine.
"I think the take-home message for clinicians is very important," she added. "This large study of nearly 300 children who were treated after cardiac arrest at 38 different pediatric health care facilities in the United States clearly indicates that lower-than-normal body temperature is not necessary. That finding is very helpful, because body-cooling is a time-consuming and complex therapy that can also put additional physical stress on the children being treated. Thanks to the study, we now know that such lower-than-normal body temperature is not necessary."
Because about two-thirds of the 6,000 U.S. children who undergo cardiac arrest (often from choking or near-drowning) each year die or suffer permanent neurologic damage, finding ways to improve their odds during treatment has been an urgent quest among pediatric critical care providers. Until recently, however, there had been no large-scale multi-center studies aimed at determining whether the demonstrated positive effects of body-cooling in adults after heart arrest could also be counted on to help similarly affected children.
The trials, funded by the National Heart, Lung, and Blood Institute (U01-HL-094339 and U01-HL-094345) of the National Institutes of Health and titled "Therapeutic Hypothermia after Out-of-Hospital Cardiac Arrest in Children," were based on treatment data collected by dozens of investigators at 38 U.S. children's hospitals. The study included nearly 300 participants (two days to 18 years old) who were brought to hospitals after cardiac arrest.
Using specially designed, water-cooled blankets over a period of five days, the caregivers lowered body temperatures in half of the post-heart arrest subjects by about six degrees Fahrenheit below normal, on average. In the other half of the cohort, normal body temperature was maintained during the same period.
Because maintaining normal body temperature required that the treating clinicians prevent fever, it now seems clear that effectiveness of body cooling among adult heart-arrest patients -- documented during studies in the early 2000s -- was likely the result of the fever prevention, Dr. Meert said.
While noting that the trial will soon be accompanied by a second study designed to evaluate body-cooling therapy in children who suffer in-hospital cardiac arrest, Dr. Meert pointed out that the findings provide a compelling example of how "clinical care and clinical research" are both essential to establishing the highest-quality treatment for pediatric patients.
"Doing clinical research as both a caregiver and a scientist is very important," she said. "Taking care of patients at bedside is how we learn what questions need to be asked - and doing the scientific research later is how we come up with answers to those questions in an organized, systematic fashion.
"I also want to emphasize the importance of collaborative research in pediatric critical care," added Dr. Meert, who has published numerous studies in her field. "Thanks to the collaborative efforts from researchers across the country and specifically at the University of Michigan and University of Utah's School of Medicine, we were able to come up with a finding that has the potential to help children better recover from cardiac arrest in the future."
Dr. Meert also praised the efforts of WSU Professor of Pediatrics Seetha Shankaran, M.D. (also a co-author) - a nationally recognized pioneer in perinatal research aimed at helping infants who suffer brain injury from oxygen deprivation during birth.
"Thanks to their tireless efforts - and those of the courageous investigators who went into the children's hospitals and interviewed stressed family members soon after the children were brought there as a result of cardiac arrest - we've taken another important step in being able to identify the best and most effective therapy for children who urgently need care," Dr. Meert said.