CHICAGO — Sick children who are admitted to pediatric intensive care units during the evening rather than during the day are slightly more likely to die in the first 48 hours of care, a study found.
Researchers did not determine why the difference exists, but fatigue, lighter staffing levels and less experienced doctors and nurses working night shifts could all be factors, said one of the study's authors, Dr. James P. Marcin.
Lab results and certain equipment — like MRI machines — also are not always as readily available at night, said Marcin, a pediatric ICU physician at the University of California Davis Children's Hospital.
The study, which analyzed 20,547 admissions to 15 pediatric ICUs from 1995 to 2001, appears in the June edition of Pediatrics, being issued today.
The study focused on the less than 500 deaths that occurred within 48 hours of admission, since they would be the ones most likely to be affected by the early hours of care. Researchers also made adjustments to make sure the severity of cases being compared was similar.
Children can be admitted to pediatric ICUs because they have cancer, after being treated in emergency rooms for illnesses like asthma or pneumonia, or after surgery.
The mortality rate for children admitted during the day was 2.2 percent. But for children admitted during the evening — defined as 5 p.m. to 7 a.m. — the death rate increased to 2.8 percent, researchers found.
Marcin said that although the difference is small, it is statistically significant, and it increases when considering the cases of the sickest children for whom prompt and expert treatment might be the most needed.
For instance, for children admitted with shock, the death rate rose from 4.7 percent for daytime admissions to 12 percent when the patients were admitted at night. For children with congenital cardiovascular disease, the mortality rate increased from 1 percent to 3.3 percent when admitted at night.
Denise Goodman, an attending physician in the pediatric ICU at Children's Memorial Hospital in Chicago, said she thought the study was interesting, but she wished more than 15 pediatric ICUs had been studied.
The study's message isn't that parents should wait to get medical treatment for their children until daytime, Goodman said, but that hospitals need to evaluate their nighttime care.
"As hospitals look at ways to improve patient safety, they need to look at things not just in a global way — like how many nurses they have or how many pharmacists they hire or buying the fanciest piece of equipment — but they have to look much more methodically at the ebb and flow of care through the course of an individual patient encounter," she said.
Marcin and Goodman both noted the data was collected before new regulations went into place last year limiting the amount of hours residents can work in a week — which could decrease the role fatigue plays in mortality rates.
The results echo a Canadian study that suggested patients were more likely to die in a hospital if they were admitted on a weekend compared to during the week, and a German study of 380,000 births that found higher mortality rates among babies born at night — although less than 100 infants died total.
The latest study found no difference in mortality rates between weekend and weekday admissions.