Emergency department contributors to ambulance diversion: a quantitative analysis

Area of Science:

• Emergency Medicine
• Health Services Research
• Healthcare Operations

Background:

• Ambulance diversion is a critical issue in emergency departments (EDs), impacting patient access and care.
• Understanding the factors contributing to ambulance diversion is essential for optimizing ED flow and resource allocation.

Purpose of the Study:

• To investigate the relationship between physician, nursing, and patient-related factors and the occurrence of ambulance diversion in an urban emergency department.
• To identify key determinants of ambulance diversion to inform operational strategies.

Main Methods:

• A time series analysis was conducted using data from one ED in Toronto, Ontario, Canada, over a 12-month period (1999).
• Data included 1,095 consecutive 8-hour intervals, examining ambulance diversion duration in relation to nurse hours, on-duty physicians, and boarded patients.
• Covariates such as patient volume, assessment time, and boarding time were incorporated into the analysis.

Main Results:

• Ambulance diversion duration was significantly associated with the number of admitted patients boarded in the ED, patient admission rates per interval, assessment time, and boarding time.
• Ambulance arrivals were linked to increased diversion, while walk-in patients and major trauma cases were not.
• Most emergency physicians and ED nurse hours showed no significant association with ambulance diversion.

Conclusions:

• The number of admitted patients awaiting beds in the ED is a primary driver of ambulance diversion.
• Nursing staff hours and the majority of physicians on duty do not appear to be significant factors in diversion.
• Strategies focused on reducing walk-in patient volume are unlikely to effectively decrease ambulance diversion use.