Unintentional pediatric superwarfarin exposures: do we really need a prothrombin time?

OBJECTIVE: To determine whether routine follow-up coagulation studies are useful in children with accidental exposures to rodenticides containing superwarfarin compounds.

DESIGN: Retrospective review of poison center charts involving pediatric superwarfarin exposures occurring in two 2-year periods.

SETTING: An American Association of Poison Control Centers-certified regional poison control center with an annual call volume of 55 000 calls per year from a 2-state area with a combined population of 4 million people.

OUTCOME MEASURES: Prothrombin times and/or international normalized ratios and reported clinical signs of excessive anticoagulation after exposure.

RESULTS: Of 542 children in 4 years of data collection, follow-up prothrombin times and/or international normalized ratios measurements did not detect any significant coagulation abnormalities. No child developed bleeding complications. No child required or received antidotal treatment with vitamin K.

CONCLUSION: Normal preschool-aged children with unintentional acute exposures to superwarfarin rodenticides do not require any routine follow-up laboratory studies and do not require any medical intervention.