Recovery of respiratory function in survivors with paraquat intoxication

The purpose of this study was to investigate chest radiograms and respiratory function changes, including pulmonary function tests and alveolar-arterial oxygen difference, in survivors with paraquat intoxication. Chest radiograms and pulmonary function tests for 21 paraquat-poisoned patients were performed 10 d after paraquat intoxication; 3 mo later, the tests were repeated in 16 patients who survived. Forced vital capacity, forced expiratory volume in 1 s, diffusing capacity of the lung, and alveolar-arterial oxygen difference were compromised after paraquat intoxication. Forced expiratory volume in 1 s and forced vital capacity correlated significantly with initial platelet counts (r = .453 and .443, respectively) 10 d after intoxication. The alveolar-arterial oxygen difference also correlated significantly with peak serum total bilirubin concentrations (r = .443) and initial platelet counts (r = .469). The follow-up data for respiratory functions (forced expiratory volume in 1 s: 74.33 ± 27.1% versus 97.89 ± 16.39%; forced vital capacity: 71.44 ± 26.03% versus 93.22 ± 13.92%; diffusing capacity of lung: 60.11 ± 27.61% versus 81.67 ± 24.56%; alveolar-arterial oxygen difference: 37.95 ± 24.32 mm Hg versus 7.75 ± 9.94 mm Hg) and chest radiograms of survivors with moderate to severe paraquat poisoning showed significant improvements 3 mo after intoxication. The results demonstrated that paraquat-induced respiratory function impairments could recover significantly, at least partially, with time. In addition, pulmonary structure damage improved, as shown in the follow-up chest radiographs.