Nurse staffing and patient outcomes in critical care: a concise review.

BACKGROUND: Studies over the past several decades have shown an association between nurse staffing and patient outcomes. Most of those studies were generated from general acute care units. Critically ill patients demand increased nurse staffing resources and nurses who have specialized knowledge and skills. Appropriate nurse staffing in critical care units may improve the quality of care of critically ill patients.
OBJECTIVES: To review the literature evaluating the association of nurse staffing with patient outcomes in critical care units and populations.
METHODS: An annotated review of major nursing and medical literature from 1998 to 2008 was performed to find research studies conducted in intensive care units or critical care populations where nurse staffing and patient outcomes were addressed.
RESULTS: Twenty-six studies met inclusion for this review. Most were observational studies in which outcomes were retrieved from existing large databases. There was variation in the measurement of nurse staffing and outcomes. Outcomes most frequently studied were infections, mortality, postoperative complications, and unplanned extubation. Most studies suggested that decreased nurse staffing is associated with adverse outcomes in intensive care unit patients.
CONCLUSIONS: Findings from this review demonstrate an association of nurse staffing in the intensive care unit with patient outcomes and are consistent with findings in studies of the general acute care population. A better understanding of nurse staffing needs for intensive care unit patients is important to key stakeholders when making decisions about provision of nurse resources. Additional research is necessary to demonstrate the optimal nurse staffing ratios of intensive care units.