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Multidose activated charcoal for yellow oleander poisoning

2003; Elsevier BV; Volume: 362; Issue: 9383 Linguagem: Inglês

10.1016/s0140-6736(03)14136-0

1474-547X

David N. Juurlink, Marco L.A. Sivilotti,

Pesticide Exposure and Toxicity

H A de Silva and colleagues (June 7, p 1935)1de Silva HA Fonseka MMD Pathmeswaran A et al.Multiple-dose activated charcoal for treatment of yellow oleander poisoning: a single-blind, randomised, placebo-controlled trial.Lancet. 2003; 361: 1935-1938Summary Full Text Full Text PDF PubMed Scopus (92) Google Scholar report that multiple-dose activated charcoal (MDAC) confers a survival advantage over a single dose in patients with yellow oleander poisoning. We commend the researchers for addressing a serious health concern endemic to Sri Lanka.2Eddleston M Ariaratnam CA Meyer WP et al.Epidemic of self-poisoning with seeds of the yellow oleander tree (Thevetia peruviana) in northern Sri Lanka.Trop Med Int Health. 1999; 4: 266-273Crossref PubMed Scopus (93) Google Scholar However, certain aspects of their study merit additional comment. The comparison of groups at baseline would benefit from additional specification. Because of the prognostic implications of varying degrees of depressed atrioventricular conduction and enhanced ventricular automaticity in such poisonings, a breakdown of arrhythmias and baseline heart rate would be more informative than simply categorising ventricular fibrillation and second-degree atrioventricular block together. The early death rate for individuals with yellow oleander poisoning (one of 422 at 6 h, or 0·2%) in this study is remarkably low. Moreover, premonitory arrhythmias were reported in fewer than half of the deaths. The same researchers3Fonseka MM Seneviratne SL de Silva CE Gunatilake SB de Silva HJ Yellow oleander poisoning in Sri Lanka: outcome in a secondary care hospital.Hum Exp Toxicol. 2002; 21: 293-295Crossref PubMed Scopus (17) Google Scholar and others2Eddleston M Ariaratnam CA Meyer WP et al.Epidemic of self-poisoning with seeds of the yellow oleander tree (Thevetia peruviana) in northern Sri Lanka.Trop Med Int Health. 1999; 4: 266-273Crossref PubMed Scopus (93) Google Scholar have previously suggested that deaths from yellow oleander poisoning often occur shortly after hospital admission, and are usually preceded by third degree atrioventricular block or ventricular tachyarrhythmias. Many of the deaths in this study are, therefore, unusual, yet they are essential to the study's interpretation because the absolute number of events in the two groups are sufficiently low as to render the study's conclusions statistically fragile. Another puzzling aspect of the trial is the sample size calculation, which is not straightforward. De Silva and colleagues estimate a 10% death rate for controls, citing previous work by Eddleston and colleagues,2Eddleston M Ariaratnam CA Meyer WP et al.Epidemic of self-poisoning with seeds of the yellow oleander tree (Thevetia peruviana) in northern Sri Lanka.Trop Med Int Health. 1999; 4: 266-273Crossref PubMed Scopus (93) Google Scholar involving patients treated at remote hospitals often without the benefits of pacing or digoxin immune Fab. Why did the group not rely on their own previous research,3Fonseka MM Seneviratne SL de Silva CE Gunatilake SB de Silva HJ Yellow oleander poisoning in Sri Lanka: outcome in a secondary care hospital.Hum Exp Toxicol. 2002; 21: 293-295Crossref PubMed Scopus (17) Google Scholar reporting a death rate of 2·4%. Moreover, de Silva and co-workers anticipated a 75% reduction in the risk of death in patients treated with MDAC. The basis for such optimism is unclear, since MDAC has not been shown to improve clinical outcomes associated with cardiac glycoside toxicity.4American Academy of Clinical ToxicologyEuropean Association of Poisons Centres and Clinical ToxicologistsPosition statement and practice guidelines on the use of multi-dose activated charcoal in the treatment of acute poisoning.J Toxicol Clin Toxicol. 1999; 37: 731-751Crossref PubMed Scopus (286) Google Scholar Two other aspects of the trial deserve comment. Although controversial, routine use of gastric lavage is difficult to justify, especially for late presentations (averaging 10 h in this study) after ingestion of a highly emetogenic substance. Finally, digoxin immune Fab should be standard care for patients with serious cardiac glycoside toxicity.5Eddleston M Rajapakse S Rajakanthan et al.Anti-digoxin Fab fragments in cardiotoxicity induced by ingestion of yellow oleander: a randomised controlled trial.Lancet. 2000; 355: 967-972Summary Full Text Full Text PDF PubMed Scopus (106) Google Scholar Only seven of at least 21 patients (33%) with an absolute indication for the drug (lifethreatening arrhythmias) received it. Notwithstanding its limited availability and cost, withholding this essential antidote affects this study's conclusions and generalisability. Multidose activated charcoal for yellow oleander poisoningAuthors' reply Full-Text PDF