Objectives: The mortality rate for mechanically ventilated older adults in ICUs is high. A robust research literature shows a significant association between nurse staffing, nurses’ education, and the quality of nurse work environments and mortality following common surgical procedures. A distinguishing feature of ICUs is greater investment in nursing care. The objective of this study is to determine the extent to which variation in ICU nursing characteristics—staffing, work environment, education, and experience—is associated with mortality, thus potentially illuminating strategies for improving patient outcomes.
Design: Multistate, cross-sectional study of hospitals linking nurse survey data from 2006 to 2008 with hospital administrative data and Medicare claims data from the same period. Logistic regression models with robust estimation procedures to account for clustering were used to assess the effect of critical care nursing on 30-day mortality before and after adjusting for patient, hospital, and physician characteristics.
Setting: Three hundred and three adult acute care hospitals in California, Florida, New Jersey, and Pennsylvania.
Patients: The patient sample included 55,159 older adults on mechanical ventilation admitted to a study hospital.
Measurements and Main Results: Patients in critical care units with better nurse work environments experienced 11% lower odds of 30-day mortality than those in worse nurse work environments. Additionally, each 10% point increase in the proportion of ICU nurses with a bachelor’s degree in nursing was associated with a 2% reduction in the odds of 30-day mortality, which implies that the odds on patient deaths in hospitals with 75% nurses with a bachelor’s degree in nursing would be 10% lower than in hospitals with 25% nurses with a bachelor’s degree in nursing. Critical care nurse staffing did not vary substantially across hospitals. Staffing and nurse experience were not associated with mortality after accounting for these other nurse characteristics.
Conclusions: Patients in hospitals with better critical care nurse work environments and higher proportions of critical care nurses with a bachelor’s degree in nursing experienced significantly lower odds of death.
1Clinical Research, Investigation and Systems Modeling of Acute illness (CRISMA) Center, Department of Critical Care Medicine, University of Pittsburgh, Pittsburgh, PA.
2Center for Health Outcomes and Policy Research, School of Nursing, University of Pennsylvania, Philadelphia, PA.
3Robert Wood Johnson Foundation Nurse Faculty Scholars, Philadelphia, PA.
* See also p. 1291.
All authors contributed to the conception and design of this article. Dr. Kelly contributed to analysis. All authors contributed to interpretation of results. Drs. Kelly, Sloane, and Aiken contributed to drafting and final version of the article. Drs. Kutney-Lee, McHugh, and Aiken contributed to critical revisions of the article. Drs. Kutney-Lee, McHugh, Sloane, and Aiken contributed to data collection and funding.
Supported, in part, by the National Institute of Nursing Research, National Institutes of Health (grant R01-NR004513, Aiken principal investigator [PI]) and “Advanced Training in Nursing Outcomes Research” (T32-NR007104, Aiken PI) and National Heart Lung and Blood Institute, National Institutes of Health “Experimental Therapeutics in Critical Care” (5T32-HL007820, Pinsky PI).
Dr. Kelly’s institution received grant support from the National Heart Lung and Blood Institute/National Institutes of Health (NIH) (5T32-HL007820). Dr. Kelly has disclosed that aspects of this study were presented at the International Symposium of Intensive Care and Emergency Medicine (Brussels, Belgium—March 2013), and AcademyHealth Annual Research Meeting (Baltimore, MD—June 2013), and that she received support for article research from the NIH. Dr. Kutney-Lee is employed by University of Pennsylvania. Dr. Kutney-Lee’s institution is awaiting review for grant from the National Institute of Aging. Dr. McHugh’s institution received grant support from the Robert Wood Johnson Foundation Nurse Faculty Scholars. Dr. McHugh received support for article research from the NIH. Dr. Aiken’s institution received grant support from the National Institute of Nursing Research/NIH. Dr. Aiken received support for article research from the NIH. Dr. Sloane has disclosed that he does not have any potential conflicts of interest.
Address requests for reprints to: Deena Kelly, PhD, RN, Department of Critical Care Medicine, University of Pittsburgh School of Medicine, 607 Scaife Hall, 3550 Terrace Street, Pittsburgh, PA 15213. E-mail: firstname.lastname@example.org