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Having more RNs on staff can decrease the odds of pneumonia and associated costs among hospitalized surgery patients

Having more registered nurses (RNs) on staff substantially decreases the likelihood that hospitalized patients will develop pneumonia, according to the findings of a recent study that was supported by the Agency for Healthcare Research and Quality (HS11397). The study was led by Sung-Hyun Cho, Ph.D., M.P.H., R.N., of the Korea Institute for Health and Social Affairs, Seoul, and formerly of the University of Michigan at Ann Arbor.

Dr. Cho and colleagues examined the impact of nurse staffing on adverse events that, according to an expert panel, could be minimized or prevented by adequate nurse staffing: fall/injury, pressure ulcer, problematic drug reaction, pneumonia, wound infection, and sepsis (blood infection). They examined the impact of patient and hospital characteristics and nurse staffing on the incidence of these events among 124,204 surgery patients at 232 acute care California hospitals. Surgeries ranged from coronary artery bypass surgery and rectal resection to hip procedures.

Most surgery patients (93 percent) did not suffer from any adverse events. However, when adverse events did occur, pneumonia occurred most frequently (nearly 3 percent of adverse events), and falls/injuries occurred least often. An increase of 1 hour worked by RNs per patient day was associated with an 8.9 percent decrease in the odds of pneumonia. Similarly, a 10 percent increase in the proportion of RNs to overall nursing staff was associated with a 9.5 percent decrease in the odds of pneumonia.

Overall, the occurrence of pneumonia was associated with an increase of 5.1-5.4 days in hospital length of stay, an increase of 4.67 to 5.55 percent in the probability of death, and a jump of $22,390-$28,505 in costs. Postoperative patients are at particularly high risk of pneumonia due to collapsed lung, retained secretions, and pain. Attentive lung care provided by RNs may allow these patients to avoid postoperative pulmonary infections, note the researchers. Patient characteristics had a great impact on the occurrence of adverse events, while hospital characteristics had minimal influence.

See "The effects of nurse staffing on adverse events, morbidity, mortality, and medical costs," by Dr. Cho, Shake Ketefian, Ed.D., R.N., F.A.A.N., Violet H. Barkauskas, Ph.D., R.N., F.A.A.N., and Dean G. Smith, Ph.D., in the March 2003 Nursing Research 52(2), pp. 71-79.

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