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D B Tuey

Publications and source records attributed to D B Tuey.

8 recordsLinked to original sources
PubMed1984

Clinical studies with computer-assisted initial lidocaine therapy.

A randomized prospective study compared achievement and maintenance of therapeutic plasma concentrations in patients receiving computer-assisted (CA) initial lidocaine hydrochloride therapy, designed pharmacokinetically to achieve and maintain a chosen plasma concentration, v conventional lidocaine therapy (CT). A separate audit of outcome was also conducted. The CA regimens provided more effective concentrations in the first hour than did CT, 2.65 v 1.5 micrograms/mL average. In the audit, ventricular fibrillation occurred in two of 78 CA v eight of 78 CT patients. Dosage adjustments were required in two CA patients v 33 CT patients. The CA therapy improved therapeutic precision, reduced dosage adjustments, and may have improved safety during initial lidocaine therapy before fitting to plasma concentration data for subsequent feedback. An improved clinical computer program now also fits to plasma concentration data. It is accessed and used routinely by hospitals over an international time-sharing network.

Aged↗
PubMed1977

Distribution and excretion of 2,4,5,2',4',5'-hexabromobiphenyl, the major component of Firemaster BP-6.

The intestinal absorption, distribution, and excretion of the major component of Firemaster BP-6,2,4,5,2',4',5'-hexabromobiphenyl, has been studied in the male rat. This polybrominated biphenyl was readily absorbed from the intestine, initially distributed throughout the body, and eventually stored primarily in the adipose tissue, was not subject to appreciable metabolism, and was excreted almost exclusively in the feces and at a very slow rate. Approximately 90% of an oral dose was absorbed from the intestine, and extrapolation of the rate of excretion to infinity indicates that less than 10% of the total dose would ever be excreted.

Animals↗
PubMed1977

Pharmacokinetic models for lipophilic compounds.

In many instances pharmacokinetic modeling offers the best method of interpreting the significance to man of results obtained with laboratory animals but first we must have accurate models for our laboratory animals. A physiological pharmacokinetic model has been used to simulate the disposition of polychlorinated biphenyls (PCBs) in the rat and to extrapolate results obtained with the rat to predict the disposition of PCBs in the mouse. The modeling methods have also been extended to predict the disposition of a polybrominated biphenyl (PBB) in the rat following IV, oral, and multiple oral doses. It is anticipated that with additional experience and work a physiological pharmacokinetic model can be used to predict the disposition of these and other xenobiotics in man.

Animals↗
PubMedDate not supplied

Pharmacokinetics of 3,3',5,5'-tetrachlorobiphenyl in the male rat.

The pharmacokinetics of 3,3',5,5'-tetrachlorobiphenyl (4-CB) was studied to determine the importance of chlorine position to the kinetics of polychlorinated biphenyl (PCB) distribution, metabolism, and excretion by the rat. Tissue samples and excreta were collected at times ranging from 2 hr to 42 days after intravenous injection of a single 0.6-mg/kg dose of 14C-labeled 4-CB. The relative fractions of 4-CB and its metabolites were determined in selected samples, and 4-hr bile cannulations were performed to establish the rate of biliary excretion. A mathematical model description of PCB kinetics in the rat was defined here for 4-CB and used to generate tissue and excretion concentration-time profiles for both the parent compound and its metabolites. Model predictions were in good agreement with the experimental data, and showed how the individual pharmacokinetics of 4-CB compared to several other PBC's. The rate of 4-CB metabolism and excretion was slower than would be predicted according to its degree of chlorination. The relative rates of metabolism for 4-CB and five other differently chlorinated biphenyls could be ordered according to the number of adjacent unsubstituted carbon-atom pairs they contained. It appears that chlorine position is more important than degree of chlorination because the former can alter the availability of vicinal hydrogens thought to facilitate rapid PCB metabolism by mammals.

Animals↗
PubMedDate not supplied

Use of a physiological compartmental model for the rat to describe the pharmacokinetics of several chlorinated biphenyls in the mouse.

The feasibility of extrapolating the pharmacokinetics of some chlorinated biphenyl congeners (PCB's) from one animal species to another was investigated. The fate of four differently chlorinated biphenyls previously studied in the rat was determined in the mouse The experimental tissue level, metabolism, and excretion data were then used to evaluate results predicted for each PCB after a physiological compartmental model for the rat was scaled to the mouse. Pharmacokinetic parameter values were also obtained from data in the mouse for further evaluations, and to determine whether the congener-dependent relationships previously observed in the rat were present in the mouse. The pharmacokinetics predicted by the scaled model and the results obtained when model parameters were derived from mouse data were equally descriptive of the experimental tissue distribution and excretion kinetics of the PCB's studied. Congener-dependent relationships among the PCB model parameters for the mouse were more varied than for the rat. The accuracy of the pharmacokinetic model predictions extrapolated from the rat to the mouse was primarily a function of their similar congener-dependent rates of PCB metabolism.

Animals↗