Hospital nurse practice environments and outcomes for surgical oncology patients

Health Services Research, August, 2008 by Christopher R. Friese, Eileen T. Lake, Linda H. Aiken, Jeffrey H. Silber, Julie Sochalski

NURSE PRACTICE ENVIRONMENTS AND OUTCOMES FOR SURGICAL ONCOLOGY PATIENTS

Cancer is the leading cause of death in the nation for adults below the age of 85 years (American Cancer Society 2005). Lung, breast, and colorectal cancers accounted for over $16 billion in direct care costs, and significant decline in life expectancy for affected patients (Brown, Lipscomb, and Snyder 2001). Yet there is evidence that the quality of cancer care varies substantially across institutions (Hewitt and Simone 1999; Nattinger 2003). Extensive quality measurement and improvement initiatives are underway, one of which is to increase health services research conducted in cancer patient populations (Lipscomb and Snyder 2002). It is hoped that such research will inform clinical and managerial decision-making to improve outcomes.

Studies examining the organization-outcomes relationship for cancer patients have centered on the role of surgical procedure volume (Hillner, Smith, and Desch 2000; Bach et al. 2001; Finlayson, Goodney, and Birkmeyer 2003; Hodgson et al. 2003; Schrag et al. 2003). Despite compelling findings for rarely performed, high-risk procedures, volume has been recognized as an "imperfect correlate of quality" (Hewitt and Pettiti 200l, p. 5). Recent research findings suggest that hospitals awarded comprehensive cancer center status by the National Cancer Institute have lower risk-adjusted mortality rates than hospitals of similar volume (Birkmeyer et al. 2005). These findings lead us to consider other organizational aspects of care associated with disparate outcomes for oncology patients.

Outside the cancer population, studies have documented superior postoperative outcomes among patients receiving care in hospitals with better nurse staffing (Aiken et al. 2002; Kovner et al. 2002; Needleman et al. 2002). However, as part of the Quality Chasm series, an Institute of Medicine report concluded that in addition to poor staffing, poor working conditions for registered nurses threaten patient safety (Institute of Medicine 2003). To date, no published studies have examined the association between nurse practice environments and outcomes for hospitalized cancer patients despite their high care complexity and fragile state. This paper seeks to fill that void by determining the impact of the quality of the nurse practice environment, as well as nurse staffing and educational levels, on adverse outcomes for surgical oncology patients.

The nursing practice environment has been defined as the organizational characteristics of a work setting that facilitate or constrain professional nursing practice (Lake 2002). Examples of these characteristics include the nature of nurses' relationships with managers and physicians, and the status of nurses within the hospital hierarchy. The innate complexity and unpredictability of patient care requires professional alertness and skill in "preventive, monitoring, and rectifying action" (Strauss et al. 1985, p. 71). A professional practice environment is characterized by greater registered nurse presence with the patient and greater decision-making authority and flexibility. These features enable preventive and monitoring actions and support appropriate and efficient rectifying action in the context of fragile patient conditions. Professional practice environments support nurses to function at the highest scope of clinical practice, to work effectively in an interdisciplinary team of caregivers, and to mobilize resources quickly. Through these mechanisms, professional practice environments contribute to better quality of care. Better quality of care, in turn, leads to superior outcomes. Thus, we hypothesized that hospitals with more favorable environments would have better patient outcomes.

DESIGN AND METHODS

Our secondary analysis of existing datasets was approved by our institutional review board. Patient and nurse data were stripped of any personal identifying information before analysis. This study extended the methods of an existing program of research, but applied them to a different clinical population: hospitalized surgical oncology patients (Aiken et al. 2001, 2002, 2003).

Data Sources and Linkage

Four datasets were used: (1) The 1998-1999 inpatient discharge database from the Pennsylvania Health Care Cost Containment Council (PHC4); (2) The Pennsylvania Cancer Registry records for any patient hospitalized in Pennsylvania in 1998-1999; (3) The 1999 American Hospital Association (AHA) annual survey; and (4) the survey data of Pennsylvania registered nurses collected in 1999 by the Center for Health Outcomes and Policy Research, University of Pennsylvania as part of the International Hospital Outcomes Consortium (Aiken et al. 2001). Using a unique, anonymized patient identifier, cancer registry records were linked to inpatient records closest to the hospital admission date. Data on nurse staffing, education, and the practice environment were aggregated to the hospital level. These measures, as well as key hospital characteristics from the AHA annual survey were then appended to each patient's record based upon the hospital they received care. Additionally, the National Cancer Institute's list of clinical and comprehensive cancer centers was used to verify the four hospitals in the sample with that designation (National Cancer Institute 2002).