Bed-to-nurse ratios, provision of basic nursing care, and in-hospital and 30-day mortality among acute stroke patients admitted to an intensive care unit: cross-sectional analysis of survey and administrative data.

BACKGROUND: The literature reports inconsistent evidence of the effects of nurse staffing on mortality despite continuing examination of this association.
OBJECTIVE: To examine differences in provision of basic nursing care and in-hospital and 30-day mortality by nurse staffing of ICUs and general wards among acute stroke patients admitted to ICUs during hospitalization.
DESIGN: A cross-sectional design that included survey and administrative data. SETTINGS AND PARTICIPANTS: The study included 6957 patients with hemorrhagic and ischemic stroke who were admitted to ICUs of 185 Korean hospitals.
METHODS: Nurse staffing of ICUs and general wards was graded based on the bed-to-nurse ratios of each hospital. Provision of basic care was measured by whether five activities, such as bathing and feeding assistance, were fully provided by ICU nursing staff without delegation to patient families. Hospitals were categorized into low, middle, and high mortality groups for in-hospital and 30-day mortality based on z-scores that indicated standardized difference between observed and expected mortality after controlling for patient characteristics.
RESULTS: In 83.8% of hospitals, basic care was provided fully by ICU nursing staff. The overall in-hospital and 30-day mortality rates were 21.9 and 25.4%, respectively. Hospitals with higher ICU staffing were more likely to fully provide basic care. Better ICU and general staffing tended to be associated with lower in-hospital and 30-day mortality. Compared with in-hospital mortality, 30-day mortality had a more distinct increase as nurse staffing became worse.
CONCLUSION: The findings provide evidence that nurse staffing may impact provision of basic care and patient mortality and suggest the need for policies for providing adequate nurse staffing.