The University Medical Center has joined a large-scale multicenter study that examines body-cooling treatment in children after cardiac arrest.

“This will be the largest study of its kind,” said Dr. Andreas Theodorou, a pediatric intensive care specialist for the Steele Children’s Research Center and pediatrics professor.

The Therapeutic Hypothermia After Pediatric Cardiac Arrest (THAPCA) trials first began in 2002 and are based at the University of Michigan, Theodorou said. Diamond Children’s Medical Center at UMC joined the study this past month, and will work with it for four years. The National Institutes of Health and the National Heart, Lung, and Blood Institute funded the $21 million study, which is divided between all 32 affiliated sites.

“It’s a tough study to do because you have to talk to parents in what is the most stressful time anyone can ever imagine,” Theodorou said. “It does create a challenge and requires a lot of sensitivity and compassion when we approach the parents to enroll them (the children) in the study.”

Past studies have suggested that adults who have had a cardiac arrest will have less brain injury and a better neurologic outcome if they have been kept cold, Theodorou said. This is where the THAPCA trials come in.

“We’re not completely sure if hypothermia is the correct treatment to do in post cardiac arrest with children because there hasn’t really been a clinical trial that looks at specifically children,” said Jen Deschenes, a public health graduate student and the research coordinator for the study.

The study compares the aggressive control of body temperature in children by keeping the temperature cold — at 33 degrees Celsius or 89.6 to 93.2 degrees Fahrenheit as opposed to a normal temperature of 98 degrees, Theodorou said.

The THAPCA trials will analyze an inpatient group (in-hospital cardiac arrest) and an outpatient group (cardiac arrest outside of the hospital).

“These are patients anywhere from 2 days of age to 18 years of age that have suffered cardiac arrest,” Theodorou said. However, cardiac arrest is not common in children.

In the study, two randomized groups will be evaluated and given care, he said. Eligible patients have a 50/50 chance of being put in the hypothermia (cooling) group or the normothermia (normal temperature) group, Deschenes said. Diamond Children’s anticipates five to six children will be eligible for the study. Nationally, the centers are aiming for 800 to 900 participants, Theodorou said.

“Both groups are considered a treatment group. Both groups will have aggressive control of their temperature to avoid fever,” Theodorou said. “The actual testing is during the first four to eight hours. They will be aggressively cooled and their temperature is controlled with a piece of equipment — a blanket that adjusts temperature.”

The blanket will warm or cool the body to “keep it to that precise temperature,” he said.

The temperature will be monitored two different ways. One thermometer will measure temperature in the esophagus and another will measure temperature another way, Theodorou said.

“In addition, there will be careful monitoring of all vital signs and an assortment of blood tests to make sure there’s no complications from the cooling or warming process,” he said.

After patients have finished the “maintaining of the temperature phase,” they will return to normal temperature.

Patients will also have evaluations over the phone and come back a year after their cardiac arrest for a detailed neurologic exam and a neurobehavioral evaluation, he said.

Because of the data collected from adults, people have inferred that hypothermia is the right treatment for children as well, Theodorou said but “really that question has not been answered.

“The reality is, some of the studies that have been done in other populations strongly suggest that fever is bad, but they don’t adequately prove that hypothermia or cooling is good,” he said.

Adults tend to have cardiac arrests due to primary heart problems, while children tend to have them because of a lack of oxygen, Theodorou said. One question is if a child suffering cardiac arrest is different from an adult. That question can only be answered by studying children directly, he said.

“We (Diamond Children’s) now feel we can compare and sometimes even compete with the major children’s hospitals in the country, so a project like this is exactly what we should participate in,” Theodorou said.