title: Simultaneous determination of lidocaine and its metabolites in plasma and myocardium.
abstract: No validated method exists for measuring lidocaine and its metabolites in myocardial tissue. We modified a previously described high-performance liquid chromatographic assay and applied it to plasma and to homogenized myocardial samples obtained from dogs that had received lidocaine by a double-infusion technique. Recovery of lidocaine, monoethylglycylxylidide and glycylxylidide after homogenization and extraction is reported. Assay variability, sensitivity and linearity over a wide range of sample sizes are also described. The results obtained with high-performance liquid chromatographic analysis are compared to quantitation of 14C-labeled lidocaine plus metabolites measured by an oxidation-scintillation technique. Myocardium to plasma partition coefficients for lidocaine, monoethylglycylxylidide and glycylxylidide were 2.16, 4.27, and 2.91, respectively.
mesh_terms: D000818:Animals; D001711:Biotransformation; D002851:Chromatography, High Pressure Liquid / Q000379:methods; D004285:Dogs; D005260:Female; D008012:Lidocaine / Q000031:analogs & derivatives / Q000097:blood / Q000378:metabolism*; D008297:Male; D009206:Myocardium / Q000378:metabolism*; D010084:Oxidation-Reduction
chemical_list: D008012:Lidocaine; C001306:glycinexylidide; C001173:monoethylglycinexylidide