Which intervention may be indicated for severe barbiturate toxicity but is ineffective for benzodiazepines?

Which intervention may be indicated for severe barbiturate toxicity but is ineffective for benzodiazepines?

• A. Activated charcoal
• B. Gastric lavage
• C. Flumazenil
• D. Hemodialysis

Answer: (D)

Dialysis works best for substances that are present in the blood in a form that can be drawn out and that are not tightly trapped in the body's tissues. Barbiturates, in severe overdose, can sometimes be cleared from the blood by hemodialysis because they have pharmacokinetic properties that allow extracorporeal removal, helping to rapidly reduce toxic levels and mitigate life-threatening CNS and respiratory depression. Benzodiazepines, on the other hand, are typically highly lipophilic, highly protein-bound, and spread widely into body tissues, giving them a large volume of distribution. Those characteristics make them poor candidates for clearance by dialysis, so this intervention does not effectively remove benzodiazepines. So, removing the toxin via hemodialysis may be beneficial in severe barbiturate toxicity but is ineffective for benzodiazepine overdose. (Activated charcoal and gastric lavage have broader applicability and are not uniquely effective for barbiturates over benzodiazepines, and flumazenil reverses benzodiazepine effects rather than barbiturate toxicity.)

Dialysis works best for substances that are present in the blood in a form that can be drawn out and that are not tightly trapped in the body's tissues. Barbiturates, in severe overdose, can sometimes be cleared from the blood by hemodialysis because they have pharmacokinetic properties that allow extracorporeal removal, helping to rapidly reduce toxic levels and mitigate life-threatening CNS and respiratory depression. Benzodiazepines, on the other hand, are typically highly lipophilic, highly protein-bound, and spread widely into body tissues, giving them a large volume of distribution. Those characteristics make them poor candidates for clearance by dialysis, so this intervention does not effectively remove benzodiazepines.

So, removing the toxin via hemodialysis may be beneficial in severe barbiturate toxicity but is ineffective for benzodiazepine overdose. (Activated charcoal and gastric lavage have broader applicability and are not uniquely effective for barbiturates over benzodiazepines, and flumazenil reverses benzodiazepine effects rather than barbiturate toxicity.)