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, James Marcin, M.D.
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, 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.
The mortality rate for children admitted during the day was 2.2%, but for children admitted during the evening -- defined as 5 p.m. to 7 a.m. -- the death rate increased to 2.8%, 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% for daytime admissions to 12% when the patients were admitted at night. For children with congenital cardiovascular disease, the mortality rate increased from 1% to 3.3% when admitted at night.