Biomaterial Database

An approximate model-independent method to maintain constant plasma levels of intravenous drugs. 1991

J M Bailey

Division of Cardiothoracic Anesthesia, Emory University School of Medicine, Atlanta, Georgia 30322.

To rapidly achieve and maintain constant plasma concentrations most intravenous drugs must be administered as an initial bolus followed by a combination of exponentially declining plus constant-rate infusions. In the clinical practice of anesthesia and critical care medicine this is often not practical without specialized equipment. In this paper a simpler approach of maintaining approximately constant plasma concentrations is developed using a loading dose with a two-stage infusion scheme (an initial rapid infusion reduced at a given time to a lower rate). Equations are developed for determining the rate of the infusions as well as the duration of the initial infusion by equating moments of the Laplace transform of the approximate infusion to the moments of the Laplace transform of an exact solution. This approach is independent of models and uses as parameters the moments of the curve relating the concentration following a single iv dose of unit magnitude as a function of time. The accuracy of this technique was assessed by computer simulation.

UI	MeSH Term	Description	Entries
D007262	Infusions, Intravenous	The long-term (minutes to hours) administration of a fluid into the vein through venipuncture, either by letting the fluid flow by gravity or by pumping it.	Drip Infusions,Intravenous Drip,Intravenous Infusions,Drip Infusion,Drip, Intravenous,Infusion, Drip,Infusion, Intravenous,Infusions, Drip,Intravenous Infusion
D010599	Pharmacokinetics	Dynamic and kinetic mechanisms of exogenous chemical DRUG LIBERATION; ABSORPTION; BIOLOGICAL TRANSPORT; TISSUE DISTRIBUTION; BIOTRANSFORMATION; elimination; and DRUG TOXICITY as a function of dosage, and rate of METABOLISM. LADMER, ADME and ADMET are abbreviations for liberation, absorption, distribution, metabolism, elimination, and toxicology.	ADME,ADME-Tox,ADMET,Absorption, Distribution, Metabolism, Elimination, and Toxicology,Absorption, Distribution, Metabolism, and Elimination,Drug Kinetics,Kinetics, Drug,LADMER,Liberation, Absorption, Distribution, Metabolism, Elimination, and Response
D010949	Plasma	The residual portion of BLOOD that is left after removal of BLOOD CELLS by CENTRIFUGATION without prior BLOOD COAGULATION.	Blood Plasma,Fresh Frozen Plasma,Blood Plasmas,Fresh Frozen Plasmas,Frozen Plasma, Fresh,Frozen Plasmas, Fresh,Plasma, Blood,Plasma, Fresh Frozen,Plasmas,Plasmas, Blood,Plasmas, Fresh Frozen
D003198	Computer Simulation	Computer-based representation of physical systems and phenomena such as chemical processes.	Computational Modeling,Computational Modelling,Computer Models,In silico Modeling,In silico Models,In silico Simulation,Models, Computer,Computerized Models,Computer Model,Computer Simulations,Computerized Model,In silico Model,Model, Computer,Model, Computerized,Model, In silico,Modeling, Computational,Modeling, In silico,Modelling, Computational,Simulation, Computer,Simulation, In silico,Simulations, Computer
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D013997	Time Factors	Elements of limited time intervals, contributing to particular results or situations.	Time Series,Factor, Time,Time Factor
D015233	Models, Statistical	Statistical formulations or analyses which, when applied to data and found to fit the data, are then used to verify the assumptions and parameters used in the analysis. Examples of statistical models are the linear model, binomial model, polynomial model, two-parameter model, etc.	Probabilistic Models,Statistical Models,Two-Parameter Models,Model, Statistical,Models, Binomial,Models, Polynomial,Statistical Model,Binomial Model,Binomial Models,Model, Binomial,Model, Polynomial,Model, Probabilistic,Model, Two-Parameter,Models, Probabilistic,Models, Two-Parameter,Polynomial Model,Polynomial Models,Probabilistic Model,Two Parameter Models,Two-Parameter Model
D016014	Linear Models	Statistical models in which the value of a parameter for a given value of a factor is assumed to be equal to a + bx, where a and b are constants. The models predict a linear regression.	Linear Regression,Log-Linear Models,Models, Linear,Linear Model,Linear Regressions,Log Linear Models,Log-Linear Model,Model, Linear,Model, Log-Linear,Models, Log-Linear,Regression, Linear,Regressions, Linear