Although some studies have portrayed tight blood sugar control as a potential means of lowering infection rates in critically ill adults, a new study-led by principal investigator Michael Agus, MD, director of the Medicine Critical Care Program at Boston Children's Hospital-found no indication that the approach benefits pediatric patients undergoing heart surgery. The results of the Safe Pediatric Euglycemia in Cardiac Surgery (SPECS) trial, which was conducted at Boston Children's and at the University of Michigan C.S. Mott Children's Hospital, will appear in the September 7 online edition of the New England Journal of Medicine and in the September 27 print version of the publication.
SPECS examined the effects of tight glycemic control with insulin compared to standard glucose management in 980 children hospitalized in the cardiac intensive care unit (CICU). All of these patients, who ranged in age from newborn to age 3, underwent open heart surgery with heart-lung bypass. "The cardiac problems faced by the children in our patient population are fundamentally different than the cardiac problems affecting adults," says Agus, Boston Children's Hospital and Harvard Medical School. "But we chose to focus on CICU patients because the cardiac arena is where the bulk of the benefits have been observed in adults."
Although Agus and his fellow researchers discovered that using insulin to maintain normal blood sugar levels had no demonstrable impact on the incidence of care-related infections (such as surgical site infections and pneumonia), length of stay in the CICU, organ failure or mortality, they did reach other key milestones. "There were two successes for this trial," explains Agus. "One was that we were able to show that children and adults are different when it comes to the benefit of glucose control in an CICU. We were also able to demonstrate that we can safely control glucose in a young, vulnerable, sick population."
The research team used subcutaneous glucose monitors and a custom insulin-dosing algorithm that took continuous values into account, only making changes based on a specific blood value. Consequently, Agus notes, "we put together a system that achieved normal glucose control with the lowest hypoglycemia rate ever documented in a prospective trial."