A  University of Michigan study, published in the March 2010 issue of Medical Care, researchers compared a set of critical factors that can affect hospital deaths: hospital occupancy, nurse staffing levels, weekend admission and seasonal influenza.


Hospital admission when beds are filled to capacity can lead more deaths.  The study found a high occupancy increases the risk of dying in the hospital by 5.6 percent.


Also, weekend admission increased the death risk by 7.5 percent and admission during widespread seasonal flu had the greatest impact by increasing the risk of death by 11.7 percent, according to the study. Having more nurses made patients safer, decreasing the risk of death by 6 percent.


Because of the size of the patients included,  166,920 adults that were admitted to 39 Michigan hospitals over three years, the researchers expanded their findings to make conclusions about  hospitals across the United States.


“The study establishes that there is indeed a connection between hospital occupancy and death rates in U.S. hospitals,” says lead author Peter L. Schilling, M.D., M.Sc., an orthopedic surgery resident at U-M Health System.


Dr. Schilling stated, “It’s important to emphasize though that this study does not identify a specific occupancy level above which patient care suffers and deaths abruptly become more common. The key occupancy level may differ for each hospital.”  


While this study is not the first to show that these factors are associated with in-hospital mortality, this study is the first to compare all four at once.


“The study further establishes each factor as a major predictor of hospital deaths but the good news is that each can be modified in some way,” says co-author Darrell A. Campbell Jr., M.D., chief of clinical affairs at the U-M Health System.


The researchers evaluated the daily occupancy of the hospitals every day for the years 2003-2006. On average, patients in the study were admitted while hospital occupancy was 73 percent of full capacity. One-third of patients were admitted on high occupancy days, at average levels of 80 percent or more.


Study patients were admitted after emergency room evaluation for pneumonia, hip fracture, gastrointestinal bleeding, heart attack, or congestive heart failure.


“Hospital occupancy changes from day to day, so patients shouldn’t try to choose a hospital based on its occupancy level,” says co-author Dr. Matthew M. Davis.  “But these kinds of study findings should prompt hospitals to look at the flow of patients and processes of their care teams during high occupancy times. Those are more challenging moments when more things can go wrong.”


What’s also unique about the U-M study is it’s the first U.S. research and evaluate the concept of “access block,” a phenomenon believed to happen when a full hospital prevents emergency room patients from accessing an inpatient hospital bed, thus prolonging wait times and delaying time-critical inpatient care.


Hospital administrators do have the ability to regulate to a large degree, a hospital’s occupancy rate.  For example, the number of elective surgeries can be altered, in terms of scheduling changes.  The authors acknowledge that limiting the profitable procedures can cost money, since they have become increasingly more important to the hospitals’ financial health in recent years.


Source:  Medical Care Vol. 48, No. 3, March 2010