Overstaffing and Understaffing Are Associated With Adverse Events In a Level III Neonatal Intensive Care Unit

This study evaluates the association between the nurse-to-patient ratio (NPR) and adverse events (AEs) in a level III neonatal intensive care unit (NICU).

This retrospective register study used data from 2020 to 2022 from 3 digital sources: a patient safety incident reporting database, the unit's nurse shift scheduling system, and the hospital information system. The NPR was calculated using the following categories to define patient care intensity: 0.33:1, 0.75:1, 1:1, and 1.5:1, based on the number of patients and nurses assigned to each shift.

A total of 382 AEs were reported during the study. Most of the AEs occurred while the NICU was understaffed (61%, n=232) or overstaffed (29.8%, n=114). They also frequently occurred during shift overlaps (26%, n=101) and during morning shifts (49%, n=186). When AEs occurred, there was a significant difference in how the patient number was divided between different shift-level staffing in intensive care (P=0.0013) and in high maintenance intensive care (P<0.0001).

The risk for AEs is increased during overstaffing and understaffing, which is why it is important to aim for the optimal NPR to prevent AEs. The review of AE reports can identify unit-specific factors such as shift overlap and high-risk shifts, which may guide effective shift planning and prevent AEs, thereby enhancing patient safety. Therefore, it is essential to regularly review AE reports.