Problems for Discussion - 2 - Anticonvulsants - Carbamazepine

A 38-year-old woman with a background of bipolar disorder presents 2 hours after ingestion of 70 x 200 mg Tegretol CR (controlled-release carbamazepine) tablets. She is drowsy but oriented with pulse 110 bpm, BP 120/60 mmHg, afebrile. ECG sinus rhythm, QRS 95 msec.

1. Discuss the options available for gastrointestinal decontamination in this patient.
2. What is the value of serial serum carbamazepine estimations in such an overdose?

You are consulted by the ICU consultant regarding a 24-year-old man who was admitted 2 days ago with coma of unknown origin. It has been learned from a family member that he takes carbamazepine for control of his epilepsy. A serum level performed on blood from this morning was 156 micromole/L.

The patient is unconscious. He flexes to pain. He is intubated and ventilated with a pulse 120 bpm, BP 100/50 mmHg, T 37.2 0C. He has 5 mm pupils bilaterally, dry mouth, absent bowel sounds. He is biochemically normal and has had a normal chest X-ray, head CT and lumbar puncture in the past 24 hours.

1. What other information would be helpful regarding this potential overdose?
2. Discuss the role of extracorporeal methods of drug removal in severe carbamazepine poisoning. When and what method would be indicated in this patient?