Conventional haemodialysis significantly lowers toxic levels of phenobarbital

Sir,

Phenobarbital overdose management involves therapy designed to enhance elimination of the drug. Haemoperfusion is generally viewed as the most effective means for the removal of the drug [1]. We report a case of severe barbiturate overdose where haemodialysis led to a significant decrease in blood drug levels. We feel that this report illustrates that haemodialysis is an effective measure in the treatment of barbiturate overdose and that charcoal haemoperfusion cannot be considered as the sole indicated extracorporeal therapy.

A 79-year-old man was admitted in our ICU after phenobarbital overdose complicated by aspiration pneumonia. He was unconscious and needed mechanical ventilation. His blood pressure was 104/61 mmHg and heart rate was 120 beats/min. There was no focal neurological defect. Serum phenobarbital level at admission was 180 mg/l (therapeutic level: 15–30 mg/l). Haemodialysis was performed on day 1 for 6 h with an internal jugular dual-lumen catheter (Arrow, Reading, PA). A 1.1 m2 polyamide haemodialysis membrane (Polyflux S; Gambro, Hechingen, Germany) was used for the procedure. The blood flow rate was 180 ml/min and the dialysate flow rate was 500 ml/min. A second haemodialysis was performed for 4 h with the same membrane and parameters, except the blood flow value was 200 ml/min. Barbiturate blood levels were determined before and after each procedure and decreased from 53% and 38%, respectively (Figure 1). The patient was discharged from ICU on day 22, the prolonged hospitalization time was due to a Pseudomonas ventilator-associated pneumonia.



View larger version (10K):
[in this window]
[in a new window]
 
Fig. 1. Phenobarbital levels during the hospitalization. The timing of the haemodialysis procedure is indicated. HD, haemodialysis.

 
Whereas charcoal haemoperfusion is considered as the recommended form of extracorporeal therapy in phenobarbital overdose, its pharmacokinetic effects and feasibility remain a mater of debate. Haemodialysis, a widely available procedure in ICU, is also recommended when the phenobarbital level exceeds 150 mg/l [2], but its efficiency seems lower [3].

However, Palmer [4] showed that the use of a high-efficiency dialyser with high blood flow rates (400 ml/min) is effective for patients with life-threatening phenobarbital poisoning, leading to a 59% decrease in phenobarbital blood levels in 4 h. Nevertheless, the use of a high blood flow rate is not always possible in the acute setting, but our data show that conventional haemodialysis remains effective, leading to similar phenobarbital blood level reduction, and should be considered as a valuable therapeutic option in patients with severe phenobarbital overdose.

Conflict of interest statement. None declared.

Frederic Jacobs and Francois G. Brivet

Service de Réanimation Médicale Hôpital Antoine Béclère Clamart, France Email: frederic.jacobs{at}abc.ap-hop-paris.fr

References

  1. Mokhlesi B, Leikin J, Murray P et al. Adult toxicology in critical care. Part II: specific poisonings. Chest 2003; 123: 897–922[Free Full Text]
  2. Frejaville JP, Bourdon R. Toxicologie Clinique et Analytique, 2ne edn. Flammarion Medecine-Science, Paris: 1975; 283
  3. Gelfand M. Hemoperfusion in drug overdose. JAMA 1978; 240: 2761–2762
  4. Palmer B. Effectiveness of hemodialysis in the extracorporeal therapy of phenobarbital overdose. Am J Kidney Dis 2000; 36: 640–643[ISI][Medline]




This Article
Extract
FREE Full Text (PDF)
Alert me when this article is cited
Alert me if a correction is posted
Services
Email this article to a friend
Similar articles in this journal
Similar articles in ISI Web of Science
Similar articles in PubMed
Alert me to new issues of the journal
Add to My Personal Archive
Download to citation manager
Disclaimer
Request Permissions
Google Scholar
Articles by Jacobs, F.
Articles by Brivet, F. G.
PubMed
PubMed Citation
Articles by Jacobs, F.
Articles by Brivet, F. G.