The association of registered nurse staffing levels and patient outcomes

If hospitals added one more full-time registered nurse on staff to care for patients, the number of hospital-related deaths in the United States could decrease significantly, according to a new review.

However, cost concerns and a worsening nursing shortage might make this an unlikely scenario.

When asked how hospital administrators can be better made aware of these possible rates of improved patient outcomes, lead review author Robert Kane, M.D., said, “The issue is not making them aware of the possibility, it's convincing them that it is in their best interests to act on it. From a business perspective, the savings in reduced lengths of stay would not offset the costs of the added staffing. The case would have to be made in terms of image and liability.”

The systematic review aimed to examine whether there was a link between a hospital's registered nurse-to-patient ratio and the health outcome of the patients under their care.

Kane, of the University of Minnesota School of Public Health, and colleagues write that “nurses are crucial to providing high-quality care,” and “increasing the nurse-to-patient ratios has been recommended as a means to improve patient safety.”

The review appears in the December issue of the journal Medical Care .

The researchers evaluated 27 studies of patient outcomes in relation to the registered nurse-to-patient ratio. Per shift, RN staffing averaged about three patients per RN in intensive care units, four patients per RN on surgical units and four patients per RN for medical patients. Registered nurse staffing ratios came from the American Hospital Association and other nursing surveys.

The studies included in the review used data on patient outcome rates from sources such as the Uniform Health Discharge Data Sets and Centers for Medicare and Medicaid Services databases.

Kane and fellow reviewers found that a greater number of RNs on staff was associated with a reduction in the number of hospital-related deaths and other negative outcomes. Their results showed that by increasing the number of full-time RNs on staff per day by one, there were 9 percent fewer hospital-related deaths in intensive care units, 16 percent fewer in surgical patients and 6 percent fewer deaths in medical patients.

For every 1,000 hospitalized patients, the reviewers estimated that an increase by one full-time RN per patient day could save five patient lives in intensive care units, five lives on medical floors and six surgical patient lives.

Moreover, increasing staffing by one RN per patient day resulted in lower rates of hospital-acquired pneumonia, respiratory failure and cardiac arrest in intensive care units. Patients' length of stay in the hospital was also shorter by 34 percent in intensive care units and by 31 percent in surgical units.

The review acknowledges that while increased nurse-patient ratios can lead to better patient outcomes, it is difficult to maintain a reasonable number of RNs on staff in light of the current shortage of available RNs.

“A sufficient supply of nurses is critical to providing our nation's population with quality health care as these studies note; yet, hospitals are currently facing a nursing shortage,” agreed Jo Ann Webb, senior director of federal relations and policy for the American Organization of Nurse Executives. “This need will only be exacerbated in the coming years to accommodate growing patient needs and to replace retiring nurses.”

“The U.S. Bureau of Labor Statistics has projected that by 2014, our nation will need an additional 1.2 million new and replacement nurses,” Webb said.

Medical Care : Contact Sue Houchin at (317) 796-5752 or [email protected] or visit: http://www.lww-medicalcare.com

Kane RL, et al. The association of registered nurse staffing levels and patient outcomes: systematic review and meta-analysis. Med Care 45(12), 2007.