Association of shift-level organizational factors with nosocomial infection in the neonatal intensive care unit

Objective To evaluate the association between shift-level organizational data (unit occupancy, nursing overtime ratios (OTRs), and nursing provision ratios (NPRs)) with nosocomial infection (NI) among very preterm infants in the Neonatal Intensive Care Unit (NICU). Study Design Multicentre, retrospective cohort study, including 1921 infants 230–326 weeks’ gestation admitted to three tertiary-level NICUs in Quebec between 2014-2018. Patient characteristics and outcomes (NI) were obtained from the Canadian Neonatal Network database and linked to administrative data. For each shift, unit occupancy (occupied/total beds), OTR (nursing overtime hours/total nursing hours), and NPR (number of actual/number of recommended nurses) were calculated. Mixed-effect logistic regression models were used to calculate adjusted odds ratios (aOR) for the association of organizational factors (mean over 3 days) with the risk of NI on the following day for each infant. Results Rate of NI was 11.5% (220/1921). Overall, median occupancy was 88.7% [interquartile range, IQR, 81.0-94.6], OTR 4.4% [IQR 1.5-7.6], and NPR 101.1% [IQR 85.5-125.1]. A higher 3-day mean OTR was associated with higher odds of NI (aOR 1.08, 95% CI 1.02-1.15), a higher 3-day mean NPR was associated lower odds of NI (aOR 0.96, 95% CI 0.95-0.98), and occupancy was not associated with NI (aOR, 0.99, 95% CI 0.96-1.02). These findings were consistent across multiple sensitivity analyses. Conclusion Nursing overtime and nursing provision are associated with the adjusted odds of NI among very preterm infants in the NICU. Further interventional research is needed to infer causality.