A common practice of successive 12-hour shifts for U.S. hospital nurses leaves many with serious sleep deprivation, higher risk of health problems, and more odds of making patient errors, according to a University of Maryland, Baltimore (UMB) study presented today at the 24th annual meeting of the Associated Professional Sleep Societies in San Antonio.

The 12-hour shift trend started in the 1970s and 1980s when there were nursing shortages, said Jeanne Geiger-Brown, PhD, RN, associate professor with the School of Nursing at UMB. Hospitals started giving nurses more benefits and bonuses, eventually leading to emphasis on 12-hour shifts, negotiated by the nursing profession, while hospitals saw that the change made nurses happy and bought into it, she said.

"Nurses often prefer working a bunch of 12-houer shifts and then lots of time off. But, I contend that it is not a good thing for nurse planning," said Geiger-Brown. The study involved 80 registered nurses, working three successive 12-hour shifts, either day or night. "We were surprised at the short duration of sleep that nurses achieve between 12-hour shifts. Over 50 percent of shifts were longer than 12.5 hours, and with long commutes and family responsibilities, nurses have very little opportunity to rest between shifts."

The study also found that the average total sleep time between 12-hours shifts was only 5.5 hours. Night-shift nurses averaged only about 5.2 hours of sleep, and the quality of their sleep was extremely fragmented. People who are sleep deprived experience microsleep periods, little lapses in attention, and intershift fatigue, "meaning that on the next shift you don't fully recover from the previous one," said Geiger-Brown.

Geiger-Brown was the co-author of a review article in the March issue of The Journal of Nursing Administration, "Is it Time to Pull the Plug on 12-Hour Shifts?" It analyzed evidence from several recent scientific studies of the safety risks involved with long work hours, and challenges the current scheduling paradigm.

"Few hospitals offer alternatives to the pattern," Geiger-Brown commented. "There is increasing evidence that 12-hour shifts adversely affect performance. In 10 previously published studies of the effects of 12-hour shifts, none showed positive effects, while four showed negative effects on performance.

Most recent studies cited in the article point to an increase in patient care errors related to successive 12-hour shifts. Geiger-Brown cites one study of 393 nurses on 5,317 shifts who were surveyed anonymously. The odds of making errors by those who reported working more than 12 hours in shifts was three times greater than nurses who reported working 8.5 hour shifts.

Experiencing partial sleep deprivation chronically, over many years, is dangerous to the nurses' health and to the patients. The most common problems with an over emphasis on 12-hour shifts are needle-stick injuries, musculoskeletal disorders, drowsy driving, and other health breakdowns related to sleep deprivation.

The authors don't expect 12-hour shifts to end anytime soon. However, there are several "tools" hospitals can deploy to help nurses and hospital administrators better manage the practice, such as courses in harm reduction, fatigue risk management, and more training of nurses about the risks.

University of Maryland Baltimore