Rosh Emergency Medicine Practice Test

In the treatment of a patient with lithium toxicity, which intervention is most appropriate?

1. Gastrointestinal decontamination with oral activated charcoal

2. Hemodialysis

3. Intravenous hydration with isotonic saline

4. Intravenous hydration with isotonic saline and hydrochlorothiazide

The correct answer is: Intravenous hydration with isotonic saline

In the treatment of lithium toxicity, intravenous hydration with isotonic saline is a key management strategy, particularly when the patient presents with mild to moderate toxicity. Adequate hydration helps to enhance the renal clearance of lithium, as this drug is primarily eliminated by the kidneys. Providing isotonic saline supports kidney function and encourages diuresis, which can help lower lithium levels in the bloodstream. In situations where lithium toxicity is present, maintaining hydration is crucial because dehydration can exacerbately concentrate lithium levels and worsen the toxicity. While gastrointestinal decontamination with oral activated charcoal can be beneficial in cases of acute lithium overdose if the patient presents soon after ingestion, its effectiveness diminishes significantly after several hours post-ingestion and is not the primary treatment for established toxicity. Hemodialysis is reserved for severe cases of lithium toxicity, particularly when there is renal failure or life-threatening symptoms, making it a secondary option. The combination of intravenous hydration and hydrochlorothiazide is not commonly the first-line treatment for lithium toxicity; diuretics can sometimes increase lithium levels and are typically avoided unless there's a specific indication. Thus, intravenous hydration with isotonic saline is the most appropriate initial intervention for managing lithium toxicity, promoting renal clearance of the drug and improving overall patient outcomes.