BACKGROUND: Activated charcoal (AC) is one of the interventions more frequently recommended
by poison centers. For instance, in 2020, 32,646 poisoned patients were treated with AC in
the United States. This decontamination method has the potential to prevent toxicity and to
decrease its severity, but its use is associated with adverse effects and has a poor
palatability. Therefore, we developed a research program named CHARPP (activated CHARcoal in
Poisoned Patients) aiming to describe the risks and benefits associated with the use of AC.
The Clinical Toxicology Recommendations Collaborative (CTRC) already published a systematic
review and is currently working on recommendations of use. The first phase of our research
program included: a retrospective study and a validation of the Poison Severity Score. The
last phase includes a randomized controlled trial (RCT) preceded by a feasibility study in
adults and children to compare outcomes in patients who received AC as per the CTRC
recommendations vs those who did not.
OBJECTIVES: This concerns the CHARPP RCT feasibility study which aims to evaluate the
possibility of conducting a large multicenter RCT comparing outcomes between poisoned
patients who received AC as per the CTRC recommendations and who received AC as per current
practice. The targeted primary outcomes includes: 1) recruitment success (100 patients total
at the two poison centers associated with academic hospitals and greater than one patient
enrolled/hospital/month), 2) protocol adherence (at least 95% of the patient randomized in
the CTRC recommendations group received AC in less than two hours after group allocation if
AC was recommended or did not received it if it was not recommended) and, 3) lost to
follow-up (less than 5%). As secondary outcomes, progression of toxicity measured by the
Poison Severity Score (and the SOFA score for adults or PELODS score for children),
mortality, length of stay in the intensive care unit and hospital, duration of mechanical
ventilation, functional outcomes and adverse events will also be described for both groups.
METHODS: This randomized concealed multicenter trial will take place in at least two poison
centres and at least four Canadian academic hospitals including at least one pediatric
center. Patients who presented to the hospital less than 8h after the ingestion of a
potentially toxic dose of a carbo-adsorbable substance will be included. Patients requiring
or who will likely require another gastro-intestinal decontamination method, who have a
contraindication to receive AC, or who ingested a substance with an entero-hepatic
circulation requiring multi-dose AC will be excluded. Once the poison centre has identified
an eligible patient, we will use a web-based system to perform a randomization in random
blocks of two or four. The specialist in poison information will then refer either to the
CTRC recommendations or to their current protocols for the use of AC. Co-interventions will
be standardized as per the poison centre protocols. Follow up will be done every 8h by the
poison centres who will also collect data regarding progression of toxicity and relevant
outcomes. The research assistant who will extract data will be blinded to study allocation.
Only a descriptive analysis will be done for the pilot trial. Data from paediatric patients
will be analysed separately. A data and safety monitoring board independent from the study
group will follow the results and approve or not the continuation of the study.
RELEVANCE: This will be an excellent opportunity to develop collaborations between poison
centers and key actors who will be involved in a larger trial. The results of the research
program CHARPP have the potential to influence policies, poison centers recommendations,
clinicians' practices and to improve poisoned patients' outcomes.