U.S. researchers say they found nurses who worked in hospital intensive care units may get less regular sleep than other nurses and may commit more errors.

Researchers at Baylor College of Medicine in Houston assessed the overall sleep quality and vigilance among intensive care unit nurses at the beginning and end of their shift. They compared their findings with similar measurements in floor nurses.

The intensive care nurses and the floor nurses completed the Pittsburgh Sleep Quality Index Questionnaire and were assessed for vigilance at the beginning and end of a 12-hour shift.

The study found the errors at either end of the shift were different only for the nurses who worked in the intensive care unit group, but not on the hospital floors.

The researchers speculated the abnormal sleep and fall in vigilance demonstrated among intensive care unit nurses may have implications for patient safety.

The findings were presented in San Diego at the annual meeting of the American College of Chest Physicians.