Link seen between working conditions, infections

Higher staffing numbers yield improved outcomes

According to a study in the June 2007 issue of Medical Care,1 hospitals that have better working conditions for nurses are safer for elderly ICU patients. The study, led by Columbia University School of Nursing researchers, measured rates of hospital-associated infections.

The researchers reviewed outcomes data for more than 15,000 patients in 51 ICUs in 31 hospitals, and found that:

  • Those units with high nurse staffing levels (the average was 17 registered nurse hours per patient day) had a lower incidence of infections;
  • Higher levels of overtime hours were associated with increased rates of infection and skin ulcers (on average, nurses worked overtime 5.6% of the time).

More specifically, ICUs with higher staffing had lower incidence of central line-associated bloodstream infections. Other measures such as ventilator-associated pneumonia and skin ulcers, which are common among hospitalized patients who cannot move regularly, also were reduced in units with high staffing levels. Patients also were less likely to die within 30 days in these higher-staffed units. Increased overtime hours were associated with increased rates of catheter-associated urinary tract infection, as well as increased rates of skin ulcers on patients.

Organizational climate measured

Another variable examined by the researchers, with intriguing results, was organizational climate. "Our careful analysis found that decisions related to staffing, overtime, and overall work environment directly affected patient safety outcomes," says Andrew W. Dick, PhD, a senior health economist at the Rand Corp. and a co-author of the study.

"Organizational climate is the shared perception of the organization by its employees," explains Patricia W. Stone, PhD, MPH, RN, associate professor of nursing, Columbia University School of Nursing and the article's lead author, noting that the findings were derived from surveys of ICU nurses.

"We used some overall global measure, but the significant aspects within that are support from managers, governance issues, nurse/physician collaboration, and the competence of other nurses," says Stone. "In addition, we asked if there are good systems in place to ensure competence and continuing education." The link between organizational climate and safety, she asserts, "was found to be quite strong."

For example, she notes, organizational climate was found to be very important in preventing catheter-associated urinary tract infections. "All working conditions are affected, but this [condition] is so related to nursing care — nurses insert and care for the catheters," Stone explains. "Nobody else can pick up problems. Doctors might fill in for nurses in other areas, but not there."

In conclusion, she says, the study found that in terms of morale, organizational climate was "more important than wages alone."

Seeking solutions

Given the widespread shortage of nurses, how can short-staffed ICUs provide adequate coverage, or avoid excessive overtime? A solution must be found, argues Stone. "My recommendation is that any overtime is a problem," she says. "We need to find ways to have a flexible, qualified work force."

One possible solution, she suggests, is the development of several float nurses via cross-training. But wouldn't that mean extra hours for these nurses? "The float nurses should not work over-time either, but rather be trained to work in any area and be able to go and work in these areas," says Stone, who notes that ICU skills are probably the hardest to come by.

So, where would these floaters come from? "They would be from other units or departments," Stone explains. "At any one time, there is a variation in the hospital on the acuity and the number of patients in a given unit." In other words, during traditional "down times," say, in the ED, a nurse could float to the ICU.

Here, again, is where organizational climate comes in, says Stone. "You need a good organizational climate [for this approach to work]," she says. "There must be respect of governance, and good communications networks."

[For more information, contact:

Patricia W. Stone, PhD, MPH, RN, Associate Professor of Nursing, Columbia University School of Nursing, 617 W. 168th Street, New York, NY 10032. Phone: (212) 305-1738. Fax: (212) 305-6937.]


  1. Stone PW, Mooney-Kane C, Larson EL, Horan T, Glance LG, Zwanziger J, and Dick AW. Nurse Working Conditions and Patient Safety Outcomes. Med Care 2007; 45:571-578.