Overview
This lecture focuses on the evaluation and management of syncope (fainting) in emergency medicine, emphasizing the balance between identifying life-threatening causes and avoiding unnecessary harm from overtesting or over-admitting.
Understanding Syncope
- Syncope is a sudden, transient loss of consciousness due to global cerebral hypoperfusion (loss of blood flow to the brain).
- Distinguish syncope from altered mental status; syncope patients return to baseline rapidly.
- Most patients with syncope are fine; high-risk cases are rare but critical to identify.
Causes & Mechanisms
- The most dangerous cause of syncope is arrhythmia (abnormal heart rhythm).
- Syncope should not be confused with seizures, as seizures usually have a post-ictal period of confusion.
- Common non-cardiac causes (hypoglycemia, sodium imbalance) are rarely responsible for true syncope if the patient returns to normal.
- Orthostatic syncope often results from medications, especially in the elderly.
Evaluation & Risk Assessment
- Focus on history, physical exam, and EKG to assess risk.
- EKG is the most important test; look for clues such as Long QT, WPW (Wolff-Parkinson-White), and Brugada syndrome.
- Patients who appear normal after syncope are usually low risk, but need follow-up.
- Admit those with concerning history, abnormal findings, or significant heart disease.
EKG Findings in Syncope
- Long QT: May indicate risk for dangerous ventricular arrhythmias.
- WPW: Look for short PR interval and Delta wave; increases risk for rapid arrhythmias.
- Brugada syndrome: Only significant when accompanied by classic EKG changes and symptoms.
Diagnostic Testing & Overuse
- Routine labs and head CT scans are usually not helpful in syncope if the patient has returned to normal.
- Avoid unnecessary hospital admissions and excessive testing to reduce harm.
Decision Instruments & Clinical Judgment
- Decision rules (decision instruments) for syncope have limited success; use them as a guide, not a strict rule.
- Clinical judgment remains vital for complex presentations.
- Overly sensitive rules increase unnecessary admissions, while more specific rules risk missing true disease.
Key Terms & Definitions
- Syncope — Sudden, temporary loss of consciousness from reduced blood flow to the brain.
- Arrhythmia — Abnormal heart rhythm, potentially life-threatening.
- Long QT — Prolonged interval on EKG, associated with risk of ventricular arrhythmias.
- WPW (Wolff-Parkinson-White) — A conduction abnormality on EKG predisposing to fast arrhythmias.
- Brugada Syndrome — Genetic disorder with characteristic EKG changes and risk of sudden death.
Action Items / Next Steps
- Review EKGs for Long QT, WPW, and Brugada patterns in syncope cases.
- Emphasize thorough clinical assessment and rational testing.
- Be cautious about over-admitting; prioritize patient-centered care over defensive medicine.