Canadian Prehospital Syncope Risk Score (Prehospital CSRS)

Background: Syncope is defined as a sudden, brief loss of consciousness (LOC) followed by a rapid complete recovery. It accounts for 160,000 emergency department (ED) visits each year in Canada. Despite this, few people are hospitalized (\~15%) and even fewer will die (\~1%). Two-thirds of patients with syncope arrive at the ED by calling 911. There are many causes of syncope. Identifying patients at low risk for bad outcomes would allow paramedics to safely determine which patients need care in the ED from those who can remain home. The research team recently developed the Canadian Prehospital Syncope Risk Score (CPSRS) which accurately identified patients at low risk for 30-day serious outcomes.

Objective: The goal of this study is to validate the accuracy of the CPSRS in the prehospital setting or refine if needed to predict the risk of 30-day serious outcomes for patients with syncope.

Methods: The research team will enroll patients with syncope from five paramedic services across Canada (British Columbia - Vancouver and Kelowna areas only, London-Middlesex, York Region, Frontenac, and Ottawa). The research team will exclude patients \<18 years old, LOC \>5 minutes, changes in mental status from baseline, alcohol or drug intoxication, or language barrier. Paramedics will fill out a study data collection form with the CPSRS items and additional data should the tool need refinement. The data will be entered into a secure database and will assess patient outcomes (death and potentially life-threatening medical conditions) at 30 days. The research team will examine model accuracy using standard prediction measures and look to improve model accuracy if needed. The research team expects to enroll 4875 patients over a 1-year recruitment period based on annual call volumes.

Expected Outcomes: Once validated, the tool could reduce the number of patients transported to the hospital by identifying those at low risk. This would improve patient-oriented care, while at the same time saving valuable paramedic and ED resources.