Discussing: Quinn et al. Annals of Emergency Medicine. Prospective Validation of the San Francisco Syncope Rule to Predict Patients With Serious Outcomes
1. This 2006 prospective cohort trial aimed to validate a clinical rule to help risk stratify patients presenting to the ER with syncope in relation to short term outcomes. The rule was validated to have a sensitivity of 98% in preventing serious outcomes after syncope within 30 days.
2. The San Francisco Syncope rule is positive if the patient has a chief complaint of “shortness of breath”, a medical history of CHF, a presenting SBP <90mm Hg, a hematocrit <30%, or an abnormal ECG result (any non-sinus rhythm or new changes).
Approximately 25% of the general population will have an episode of syncope in their lifetime. Patients with syncope account for 1-2% of all Emergency Department visits and hospital admissions. Patients admitted for syncope, however, have been shown to receive little to no further diagnostic care, nor do they often receive a firm diagnosis concerning the cause of their syncope. Given this, the authors’ purpose was to validate the decision rule in a prospective cohort of consecutive ED patients by determining whether it can predict short-term serious outcomes.
Syncope was defined as “transient loss of consciousness with return to baseline neurologic function,” and patients presenting with acute syncope or pre-syncope were screened for the study. When a clinician had finished working up the selected patient, a short Web-based questionnaire was completed to evaluate for aspects of the history, ECG, vitals or lab results that pertain to the decision rule. In this trial, the decision rule was 98% sensitive and 56% specific to predict a serious outcome within 30 days. If applied in the study cohort, this clinical rule may have decreased syncope admissions by 24%.