Cardiovascular changes after achieving constant effect site concentration of propofol
Anaesthesia
|June 28, 2008
Abstract
No abstract available in PubMed .
Related Concept Videos
Time Course of Drug Effect
The progression of a drug's impact can be analyzed by examining both the concentration-time course and the effect-time course. The concentration-time course is determined by the drug's half-life and is influenced by factors such as its pharmacokinetics, including absorption, distribution, metabolism, and elimination. The effect of the drug is often related to its concentration in the plasma and is calculated using the maximum drug effect and the plasma concentration that generates 50 percent of...
Factors Affecting Drug Distribution: Organ Perfusion Rate
Drug distribution within the body is a complex process influenced by several factors, including perfusion rate, the rate at which the bloodstream transports drugs to tissue. This limitation becomes particularly significant when dealing with highly lipophilic drugs. In such cases, the rate at which the drug can move across membranes is crucial, and if the membrane is highly permeable to the drug, distribution becomes rate-limited by perfusion.
Perfusion rate-limited distribution relies on the...
Perfusion rate-limited distribution relies on the...
Parenteral Anesthetics: Overview
Intravenous anesthetics are drugs administered parenterally to induce anesthesia or sedation. Propofol is a widely used agent formulated as a 1% emulsion in soybean oil, glycerol, and egg phosphatide. It induces rapid anesthesia primarily due to its rapid distribution from the bloodstream to target tissues and is metabolized in the liver. However, it can cause significant pain on injection and hypertriglyceridemia. Fospropofol, a water-based prodrug of propofol, lacks these adverse effects.
Pharmacodynamic Models: Logarithmic Concentration–Effect Model
The log-linear model is a pharmacological framework used to describe the relationship between drug concentration and its effect. This model is particularly relevant when the observed effects range between 20% and 80% of the drug’s maximum effect (Emax), where a near-linear relationship is observed between the log of drug concentration and the measured effect. However, the log-linear model does not predict the maximum possible effect (Emax) or the effect at zero drug concentration, limiting its...
Steady State Concentration
A steady state refers to the level of a drug in the body once it has reached an equilibrium between administration and elimination. It represents the point at which the drug administration rate equals the drug elimination rate, resulting in a relatively constant concentration in the body over time. The dynamic equilibrium is crucial to ensure the drug's effectiveness with minimal risk of toxicity.
Most drugs are administered in repeated doses at fixed intervals or through continuous intravenous...
Most drugs are administered in repeated doses at fixed intervals or through continuous intravenous...
Pharmacokinetic–Pharmacodynamic Relationship: Intensity of Dose-Effect Relationship
Pharmacodynamics explores the relationship between drug concentration and its effect. In a quantal response drug, the duration of action better correlates with drug concentration, while for graded effect drugs, the intensity of response is more relevant. This intensity depends on the dose, drug removal rate, and the region of the concentration–response curve.The concentration–response curve can be divided into three regions. Region 3 (80–100% maximum response) demonstrates that even as drug...
