Analysis of Prognostic Factors in Patients with Paraquat Poisoning for Better Therapy Regimen

Background Paraquat poisoning is associated with very high mortality rate and extremely difficult to manage due to lack of antidotes. The purpose of this study was to identify prognostic factors after paraquat poisoning and discuss the efficacy of current therapy regimen. Methods In this retrospective study, 211 paraquat poisoning cases admitted to the First Affiliated Hospital, School of Medicine, Zhejiang University between 1 June 2010 and 30 April 2016 were enrolled. The demographic characteristic, medical records of clinical features, laboratory parameters, therapy regimen and the prognosis were analyzed. Results The overall survival rate was 55.45%. the mean age was 35.85 years old. Twelve patients who ingested paraquat combined with alcohol had a higher survival rate. The patients in survival group ingested less amount of paraquat, presented with lower serum creatinine level at admission, developed lower incidence of acute kidney injury and pulmonary CT deterioration. The survivors were treated with higher dosage of methylprednisolone, daily dose of aspirin, daily dose of rapamycin and lower dose of vitamin C. The frequency of hemoperfusion was much more in the survival group. The Cox regression survival analysis demonstrated larger amount of paraquat ingestion, abnormal renal function at admission or developing acute kidney injury (AKI) after admission were independent risk factors for mortality. Higher dose of methylprednisolone and aspirin were independent protective prognostic factors. Conclusions Non-survivor characteristics are larger amount of paraquat ingestion, manifestation of abnormal renal function at admission or developing AKI after admission, whereas the survivor characteristics are higher dose of methylprednisolone and aspirin.