Two large simple randomised controlled trials regarding the management and complications of acute poisoning in Sri Lanka
Ed Juszczak with Michael Eddleston and David Warrell (Oxford), Rezvi Sheriff (Colombo), and Nick Buckley (Canberra)
Deliberate self-poisoning has reached epidemic proportions in parts of the developing world where highly toxic poisons and sparse medical facilities ensure a high fatality rate. Pesticides are the major problem – the WHO estimates that they cause more than 220,000 deaths worldwide each year, most due to organophosphate insecticides. Self-poisoning is particularly important in Sri Lanka where thousands of people die each year and preventing suicide has become a national public health priority.
Multiple animal and simulated human overdose studies have shown that a single dose of activated charcoal, if given shortly after a poison is ingested, reduces absorption. Multi-dose regimens of charcoal may be effective much later for some poisons since the presence of charcoal in the intestine will interrupt the enterohepatic circulation and draw poison out of the gut vasculature into the bowel. Unfortunately, there have been no human studies of activated charcoal with clinically relevant outcomes such as death.
Trial 1 will investigate the effectiveness of activated charcoal in a three-arm, multicentre, open-label, parallel group trial, comparing single dose and multiple dose activated charcoal with no charcoal, respectively, for the treatment of acute poisoning. In addition, a trial of pralidoxime in symptomatic organophosphate poisoned patients (Trial 2) will be nested into this study.
The trials will look at unselected adult patients with all forms of acute poisoning. Primary outcome will be in-hospital mortality; secondary outcomes will include the occurrence of serious complications (respiratory arrest and time requiring assisted ventilation in organophosphate poisoning; status epilepticus in organochlorine poisoning; cardiac dysrhythmias in oleander poisoning).
The recruitment target of 4500 reached ahead of schedule in October 2004. Analysis is in progress.
Publications: 56, 57
