Evaluation of Severity Indexes of Patients with Paraquat Poisoning

1 Three indexes for evaluating the severity of paraquat poisoning based on plasma-paraquat concentration are presently in use; the curves of Proudfood et al. and Scherrmann et al. and the SIPP. Their effectiveness in determining the prognosis of patients with paraquat poisoning was evaluated.

2 To determine which index was more accurate, contingency tables of the three indexes were obtained and compared; Proudfoot's curve vs the SIPP Scherrmann's curve vs the SIPP. Proudfoot's curve and the SIPP were applied to patients admitted within 24 h after intoxication. Scherrmann's curve and the SIPP were applied to patients admitted more than 24 h after intoxication. The proportions of patients with true positive and true negative results to total patients were compared by a ratio test.

3 Proudfoot's curve was found to be more accurate than the SIPP for predicting the prognosis of patients admitted within 24 h (P < 0.05). No significant difference, however, was noted between Scherrmann's curve and the SIPP in determining the prognosis of patients admitted after more than 24 h.

4 In conclusion, Proudfoot's curve proved a better index for predicting the outcome of patients who were admitted within 24 h. However, for the prognosis of patients admitted more than 24 h after the ingestion of paraquat, further study is required.