[Paraquat poisoning. Prognostic and therapeutic evaluation in 28 cases].

Since a mouthfull of the herbicidal compound Paraquat usually results in death from caustic burns, renal tubular necrosis, circulatory failure of pulmonary fibrosis, the fact that 11 out of 28 people poisoned in the period 1972-1980 survived deserves consideration. The most significant prognostic factors appear to be: (1) the mode of penetration: all 4 patients poisoned through the skin and/or the respiratory tract survived; (2) the volume of Paraquat absorbed: death from circulatory failure occurs within less than 72 hours with more than 50 mg/kg, while 35 to 50 mg/kg produce progressive pulmonary fibrosis; (3) the content of the stomach at the time of ingestion: food can neutralize the compound; (4) the finding of gastric lesions on early endoscopy; (5) evidence of acute renal failure; finally and mostly (6) Paraquat blood levels during the first 24 hours, as measured by radioimmune assays; lethal levels are 2.0, 0.6, 0.3, 0.16 and 0.10 mg/l at 4, 6, 10, 16, and 24 hours respectively. There is no overlapping between values obtained in patients who died and survivors. In this series, the course of the intoxication, as predicted from the initial prognostic factors, was unmodified by the treatments applied (Fuller's earth, dialysis, charcoal haemoperfusion, furosemide, immediate hypooxygenation). The survival of two patients with restrictive respiratory pathology seems to be ascribable to the circumstances of poisoning rather than to the treatment.