[Prolonged hypocoagulability following the ingestion of anticoagulant raticides]

Voluntary ingestion of concentrated anticoagulant rodenticides leads to prolonged hypocoagulability sometimes accompanied by haemorrhage. The authors report 11 cases referred to the Paris Anti-Poisons Centre. The products implicated were chlorophacinone, bromadiolone, and warfarin. The time interval before medical intervention ranged from 90 minutes to 3 weeks. The absence of early clinical signs probably explains the number of late admissions. Haemorrhage of variable severity was observed in 8 cases. The prothrombin time varied with the administered dose of Vitamin K and/or coagulation factors. Three patients were lost to follow-up at days 9, 24 and 68. The other patients were treated for several weeks (27 to 82 days). Massive overdose with these rodenticides justifies stomach washout when the patients are seen early, daily check-ups of coagulability and treatment with Vitamin K at a dosage adapted to the biochemical abnormalities. Severe haemorrhage requires transfusion and the administration of factors of coagulation. The duration of the abnormalities is unpredictable; the prothrombin time should therefore be checked 48 hours after stopping Vitamin K therapy to detect any recurrence.