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Extended work shifts, common among nurses, substantially increases the likelihood of medical errors

With no State or Federal regulations restricting the number of hours a nurse may work in 24 hours or in a 7-day period, hospitals have extended nurses' work shifts and overtime to cope with the shortage of registered nurses (RNs). In many cases, nurses work a shift lasting longer than 12 hours, which triples the likelihood of medical error, according to a study supported by the Agency for Healthcare Research and Quality (HS11963). Logbooks completed in 2002 by a random nationwide sample of 393 hospital staff nurses over a 4-week period revealed that 80 percent of the time nurses worked longer shifts than scheduled, nearly 40 percent of the 5,317 work shifts they logged exceeded 12 hours, and half of them exceeded 10.5 hours.

The nurses used the logbooks to collect information about hours worked (both scheduled and actual hours), time of day worked, overtime, days off, and sleep/wake patterns, as well as information about medical errors and near errors. The logbooks also showed that 14 percent of nurses worked 16 or more consecutive hours (double shifts) at least once during the 4-week period. The longest shift worked was nearly 24 hours. Nurses left work at the end of their scheduled shift less than 20 percent of the time. They worked, on average, 55 minutes longer than scheduled each day, and one-quarter of the nurses worked more than 50 hours per week for 2 or more weeks of the 4-week period.

These long hours increase the likelihood of medical errors, notes Anne E. Rogers, Ph.D., R.N., F.A.A.N., of the University of Pennsylvania School of Nursing. The likelihood of making an error was more than three times as high when nurses worked shifts lasting 12.5 hours or more. Working overtime doubled the odds of making at least one error, regardless of how long the shift was originally scheduled. Finally, working more than 40 hours per week significantly increased the risk of making an error or near error.

See "The working hours of hospital staff nurses and patient safety," by Dr. Rogers, Wei-Ting Hwang, Ph.D., Linda D. Scott, Ph.D., R.N., and others, in the July/August 2004 Health Affairs 23(4), pp. 203-212.

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