Immediate Management of Sudden Onset Altered Mental Status in a Patient Receiving BAL (Dimercaprol)
Discontinue BAL immediately and assess for BAL-induced encephalopathy, as dimercaprol is a known neurotoxic chelator that can cause acute neurological deterioration including altered mental status, seizures, and coma.
Critical First Steps
The provided evidence addresses acute mountain sickness (AMS) rather than BAL (British Anti-Lewisite/dimercaprol) toxicity. However, based on general medical knowledge of chelation therapy complications:
Immediate Actions Required
- Stop BAL infusion immediately - dimercaprol has significant CNS toxicity and altered mental status is a medical emergency requiring immediate cessation of the offending agent
- Assess airway, breathing, and circulation - ensure patient is protecting airway and maintaining adequate oxygenation
- Obtain rapid glucose check - rule out hypoglycemia as a reversible cause of altered mental status
- Check vital signs including blood pressure - BAL can cause hypertension and tachycardia which may contribute to encephalopathy
- Obtain stat basic metabolic panel - assess for electrolyte disturbances, renal function, and acid-base status
Neurological Assessment
- Perform focused neurological examination - assess level of consciousness using Glasgow Coma Scale, pupillary responses, focal deficits, and signs of increased intracranial pressure
- Evaluate for seizure activity - BAL can lower seizure threshold; observe for subtle seizure manifestations
- Consider head CT if focal findings present - rule out structural causes including intracranial hemorrhage
Differential Diagnosis Considerations
- BAL-induced encephalopathy (most likely given temporal relationship)
- Heavy metal redistribution - BAL can mobilize metals into CNS causing acute toxicity
- Hypertensive encephalopathy - BAL commonly causes blood pressure elevation
- Underlying infection or metabolic derangement - particularly in context of heavy metal poisoning requiring chelation
Supportive Management
- Provide supplemental oxygen - maintain SpO2 >94% to optimize cerebral oxygenation
- Establish IV access if not already present - ensure ability to administer emergency medications
- Consider benzodiazepines - if seizures occur or patient is agitated (lorazepam 2-4 mg IV)
- Monitor closely - continuous cardiac monitoring and frequent neurological assessments
Disposition and Consultation
- Consult toxicology/poison control immediately - BAL toxicity requires expert guidance on further chelation strategy
- Consult nephrology if indicated - alternative chelation agents (DMSA, EDTA) may be needed depending on underlying heavy metal
- Admit to intensive care unit - altered mental status in context of chelation therapy requires close monitoring
- Do not resume BAL - consider alternative chelation strategies once patient stabilizes
Common Pitfalls
- Continuing BAL despite neurological symptoms - this can lead to irreversible CNS damage
- Attributing symptoms to underlying heavy metal poisoning - while possible, acute change during BAL administration suggests drug toxicity
- Inadequate monitoring during chelation - BAL requires close observation for adverse effects
- Failure to consider metal redistribution - BAL can paradoxically worsen CNS toxicity by mobilizing metals into brain tissue
Note: The evidence provided primarily addresses acute mountain sickness rather than BAL toxicity. The above recommendations are based on general medical knowledge of dimercaprol's known adverse effect profile and standard management of drug-induced altered mental status.