Prediction of outcome following paraquat poisoning by arterial lactate concentration-time data

The present study retrospectively analyzed 170 patients diagnosed with paraquat (PQ) poisoning with the aim of clarifying whether the arterial lactate-time (arterial lactate concentration × time between ingestion and arterial lactate measurement) was a good predictor of mortality in patients with acute PQ poisoning. The results indicated that there was a positive correlation between the arterial lactate-time and PQ concentration-time (ρ=0.485). In addition, the arterial lactate-time data exhibited a similar discriminative power to the plasma PQ concentration-time data (z=0.712; P=0.864). For the receiver operating characteristic curve analysis, the lactate-time data had an area of 0.782 with a cut-off value of 11.95 mmol/l.h (sensitivity, 64.52%; specificity, 84.42%). To calculate the predicted probability of survival for any specified time and initial arterial lactate concentration, the following formula was derived based on the logistic regression coefficients: Logit(p) = 3.066 - 0.139 × (time lag following PQ ingestion) - 0.177 × (initial arterial lactate concentration); where the probability of survivors = 1/1 + e-logit(p). Therefore, the arterial lactate-time data exhibited a good predictive power for evaluating the prognosis of patients with acute PQ poisoning.