Determining the conditions for reverse triage in emergency medical services using queueing theory

In emergency health care, there are situations where the less wounded are treated in preference to the more severely wounded, so called reverse triage. This may arise in situations such as war where soldiers are required to return to the battlefield as quickly as possible, or disaster situations where medical resources are limited in order to conserve resources for those likely to survive without requiring advanced medical care. This article is to study the reverse triage in time-critical systems, where conditions of patients may deteriorate while waiting for treatment. A queueing model with transfers and abandonments is developed to study the health care system. Using smoothed rate truncation method, sufficient conditions of reverse triage are derived, under which non-critical patients are treated with priority. For other conditions, the optimal policy is very complicated. We suggest a dynamic control policy according to the system state rather than any static priority policies.