ECG Manifestations The Poisoned Patient Ehsan Bolvardi M

ECG Manifestations: The Poisoned Patient Ehsan Bolvardi , M. D

Introduction Emergency medicine routinely evaluate and manage poisoned patients. There are numerous drugs that can cause ECG changes and lead to cardiac dysrhythmias. Five main categories: Potassium(K+) efflux blockers, Sodium(Na+) channel blockers, Sodium-potassium adenosine triphosphate (Na+/K+ ATPase) blockers, Calcium channel blockers, Beta-adrenergic blockers,

ECG for Etiology? !

Cardiac physiology

Potassium efflux blocker toxicity Antihistamines Antipsychotics Antidysrhythmics TCAs Fluoroquinolones Macrolides ECG: Prolongation of the QT interval

This ECG (taken following a 6 g quetiapine overdose):

Diagnosis?

Management Withdrawal of potential cause Correction of coexisting medical problems(K, Mg, Ca) Intravenous magnesium sulfate Electrical overdrive pacing Unsynchronized electrical defibrillation (AHA guidline)

Sodium channel blocker toxicity TCAs Carbamazepine antidysrhythmics Citalopram Cocaine phenothiazine Propranolol Verapamil ECG: Widened QRS , Right axis deviation , bradycardia, VT, VF

ECG after ingestion of 35 mg/kg doxepin

Delayed ECG with worsening TCA toxicity

management Administration of sodium Creation of an alkalosis Hypertonic saline Hyperventilation Lidocaine Avoided: antidysrhythmic (IA, IC)

Na+/K+ ATPase blocking agents and substances Digoxin Foxglove Lily of the valley Oleander ECG: Increased automaticity accompanied by slowed conduction through the AV node. Acute poisoning most closely correlates with hyperkalemia.

Diagnosis?

management Digoxine -specific antibody(Fab) fragments Atropine sulfate Cardiac pacing Phenytoin Avoid Quinidine and procainamide.

Calcium channel blocker toxicity Amlodipine(higher affinity for the peripheral vascular smooth muscle) Nicardipine Nimodipine Verapamil(strong affinity for cardiac and vascular calcium channel) Diltiazem ECG: Sinus bradycardia , Decreased AV node conduction , Intraventricular conduction defect.

Diagnosis?

management Atropine Calcium Glucagon Insulin Sodium bicarbonate

Beta-adrenergic blocker toxicity Acebutolol Atenolol Bisoprolol Carvedilol Esmolol Labetalol Metoprolol Propranolol Sotalol Timolol ECG: Sinus bradycardia , Decreased AV node conduction

Diagnosis?

management atropine, glucagon, calcium, insulin, various catecholamines, Pacemaker insertion, balloon pump, bypass

Summary Order ECG; Check: rhythm , rate , Axis, QRS widening, PR and QT interval, AV and intraventricular block, Ischemic changes;

This ECG is from a man who presented following a TCA overdose

This is an ECG from a patient of unknown age and presentation