RESUMO
In the present work, a method was developed and optimized aiming to determinate the herbicides paraquat (PQ) and diquat (DQ) in human plasma and urine samples. An initial procedure of chemical reduction of the analytes by adding NaBH4 directly in the buffered samples (pH 8.0) was performed. This procedure was necessary to convert the quaternary ammonium substances into more volatile compounds for gas chromatographic analysis. The reduction compounds were extracted with C18 cartridges (solid-phase extraction). Ethyl paraquat (EPQ) was used as internal standard (IS). Gas chromatography-mass spectrometry (GC-MS) was used to identify and quantify the analytes in selected ion monitoring (SIM) mode. The limits of detection were 0.05 mg/l for both PQ and DQ. By using the weighted least squares linear regression (1/x1/2 for plasma and 1/y for urine), the accuracy of the analytical method was improved at the lower end of the calibration curve (from 0.1 to 50 mg/l; r>0.98). This method can be readily utilized as an important tool to confirm the suspicion of PQ and/or DQ poisoning and evaluate the extent of the intoxication.
Assuntos
Diquat/sangue , Diquat/urina , Cromatografia Gasosa-Espectrometria de Massas/métodos , Paraquat/sangue , Paraquat/urina , Diquat/química , Herbicidas/sangue , Herbicidas/química , Herbicidas/urina , Humanos , Estrutura Molecular , Paraquat/química , Reprodutibilidade dos TestesAssuntos
Humanos , Cateteres de Demora/estatística & dados numéricos , Plasmaferese , Intoxicação/sangue , Intoxicação/complicações , Intoxicação/etiologia , Intoxicação/terapia , Testes de Coagulação Sanguínea , Toxicologia , Agaricus phalloides/sangue , Agaricus phalloides/intoxicação , Assepsia , Hemodinâmica , Consentimento Livre e Esclarecido , Paraquat/sangue , Paraquat/intoxicação , Consentimento do Representante Legal , Transplante de ÓrgãosAssuntos
Humanos , Plasmaferese , Toxicologia , Intoxicação/etiologia , Intoxicação/terapia , Intoxicação/complicações , Intoxicação/sangue , Testes de Coagulação Sanguínea , Cateteres de Demora/estatística & dados numéricos , Cuidados Críticos , Hemodinâmica , Paraquat/intoxicação , Paraquat/sangue , Agaricus phalloides/sangue , Agaricus phalloides/intoxicação , Assepsia , Consentimento do Representante Legal , Consentimento Livre e Esclarecido , Transplante de ÓrgãosRESUMO
Between March 1986 and March 1988, 47 consecutive patients, whose paraquat intoxication was confirmed by urine testing, were enrolled in a prospective study on the treatment of paraquat poisoning. Fourteen received a standard treatment regimen consisting of fluid replacement and oral absorbents, and 33 received high-dose cyclophosphamide and dexamethasone, in addition to standard therapy. The case fatality rate in both treatment groups (63 and 61%) was similar. In addition, all 26 patients whose paraquat serum concentrations were measured and who had a probability of survival of less than 65% according the survival curve of Hart et al. died, regardless of therapy. These included four in the cyclophosphamide/dexamethasone group and two in the standard treatment group who had prior survival probabilities between 50 and 65%. This indicated that the cut-off curve relating mortality and paraquat serum concentrations was similar in both treatment groups. High-dose cyclophosphamide/dexamethasone treatment is unlikely to improve the prognosis of paraquat poisoning.