RESUMEN
Endogenous digoxin-like immunoreactive substances (DLIS) cross-react in immunoassays of digoxin. The postmortem rise in digoxin levels in patients treated with the drug may be due to its redistribution. It is unclear what is the contribution of DLIS to this increase and whether DLIS are present postmortem in patients not treated with digoxin. The objectives of this study were to determine whether DLIS are present after death in patients not treated with digoxin, whether a postmortem increase in DLIS is detectable and whether sampling site can affect DLIS concentrations. DLIS (measured as digoxin, TDx Abott) were determined in blood samples drawn antemortem from ICU patients; postmortem samples from femoral artery and cardiac chambers were taken at least 12 h after the death of these same patients. DLIS concentrations > or = 0.2 ng/ml were measured in 44 and 40% of patients antemortem and postmortem (femoral), respectively. No difference was found in DLIS levels between antemortem and postmortem femoral and cardiac samples. Age, ICU stay and postmortem sampling time did not affect the postmortem increase in DLIS. None of the levels was in the toxic range. DLIS may be present after death and their concentration does not increase postmortem. The interpretation of postmortem digoxin concentrations that fall in the therapeutic range should be done cautiously; such measurable levels do not necessarily indicate misuse or malicious intent even in patients who had not been treated with the drug.
Asunto(s)
Digoxina/sangre , Adolescente , Adulto , Factores de Edad , Anciano , Autopsia , Digoxina/inmunología , Femenino , Inmunoensayo de Polarización Fluorescente , Humanos , Masculino , Persona de Mediana Edad , Factores de TiempoRESUMEN
Obidoxime is an oxime used in several countries as an antidote in organophosphate intoxication. Its pharmacokinetics were studied in a 20 year-old female with severe and complicated methamidophos intoxication. Obidoxime elimination half life was 6.9 h, volume of distribution 0.845 L/kg, total body clearance 85.4 mL/min, and renal clearance 69 mL/min (creatinine clearance 54 mL/min). Eighty percent of the dose was excreted in the urine over 5 h. Possible reasons for the different pharmacokinetic values as compared with values previously reported in healthy volunteers are discussed. Obidoxime dose should be adjusted according to renal function. More studies are needed to establish the therapeutic window of obidoxime in patients with organophosphate intoxication.