Monash transient ischemic attack triaging treatment: safety of a transient ischemic attack mechanism-based outpatient model of care

Abstract

Background and purpose: Controversy surrounds the need for routine hospital admission for transient ischemic attack. The Monash Transient Ischemic Attack Triaging Treatment (M3T) model adopts rapid management in the emergency department followed by outpatient management prioritized by stroke mechanism. We compared safety and processes of care between M3T and the previous model of routine admission.

Methods: Study cohorts consisted of patients managed with M3T (2004-2007) and the previous model (2003-2004). We determined 90-day stroke outcome using clinical and medical record review and data linkage to the population level state-wide hospital discharge morbidity database. We compared models of care using risk difference analysis, followed by logistic regression to adjust for previous indicators of risk. Secondary outcomes were proportions admitted, proportions undergoing carotid ultrasound, times to ultrasound and revascularization, and medication prescription.

Results: In M3T (mean age, 64.7±14.7) 85/488 (17.4%) patients were admitted compared with 117/169 (62.9%) in the previous model (mean age, 72.5±13.9). With near-complete follow-up, 90-day stroke outcome was 1.50% (95% confidence interval, 0.73%-3.05%) in M3T and 4.67% (95% confidence interval, 2.28%-9.32%) in the previous model (P=0.03). Compared with the previous model, the adjusted odds ratio of stroke for M3T was 0.46 (95% confidence interval, 0.12-1.68; P=0.24). M3T was associated with greater proportions undergoing carotid ultrasound (P<0.001) and receiving antiplatelet therapy (P=0.005).

Conclusions: The M3T system was associated with low 90-day stroke outcome in transient ischemic attack patients, providing proof of concept that these patients may be managed safely without routine hospital admission using a closely supervised protocol in the emergency department.