Pharmacology for anesthesia i
This presentation is the property of its rightful owner.
Sponsored Links
1 / 40

Pharmacology for Anesthesia I PowerPoint PPT Presentation


  • 91 Views
  • Uploaded on
  • Presentation posted in: General

Pharmacology for Anesthesia I. Introduction. What is a Drug?. Pharmacokinetics (PK). What the body does to the drug Absorption Distribution Metabolism Excretion. Absorption. The process of diffusion or transport of a drug from the site of administration to the plasma.

Download Presentation

Pharmacology for Anesthesia I

An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -

Presentation Transcript


Pharmacology for anesthesia i

Pharmacology for Anesthesia I

Introduction


What is a drug

What is a Drug?


Pharmacokinetics pk

Pharmacokinetics (PK)

What the body does to the drug

  • Absorption

  • Distribution

  • Metabolism

  • Excretion


Pharmacology for anesthesia i

Absorption

The process of diffusion or transport of a drug from the site of administration to the plasma

Skipped by administering drugs parenterally

Inhaled agents require special considerations


Fick s law

Fick’s Law

concentration gradient x surface area x diffusion coefficient

membrane thickness

Rate of Diffusion =

Permeability

Size

Diffusion coefficient =


Pharmacology for anesthesia i

Ionization State

Henderson – Hasselbalch Equation

concentration (protonated)

concentration (unprotonated)

log

= pKa - pH


Pharmacology for anesthesia i

Trapping


Distribution

Distribution

The process of diffusion of a drug throughout the body

Generally governed by the same characteristics as absorption

Vd = volume of distribution

Protein Binding


Metabolism

Metabolism

  • The enzymatic modification of the drug molecule by the body

    • Often occurs in liver

    • May occur elsewhere


Hepatic metabolism

Hepatic Metabolism


Example of phase ii prior to phase i

Example of Phase II prior to Phase I


Cyp enzymes

CYP Enzymes


Pharmacogenetics of drug metabolism

Pharmacogenetics of Drug Metabolism


Examples of drug drug interactions

Examples of Drug-Drug Interactions


Elimination

Elimination

  • The removal of the drug from the body

    • Renal

    • Hepatic

    • Respiratory

    • Cutaneous


Clearance

Clearance

  • Used to describe our ability to eliminate the active ingredient

    • Combination of metabolism and excretion

      Example of Zero order kinetics


Pharmacology for anesthesia i

Distribution and Clearance

  • First Order Kinetics

    • Single compartment model

    • Double compartment model

    • Three compartment model

    • Etc.


Absorption and clearance

Absorption and Clearance


Effect not always governed by plasma concentration

Effect Not Always Governed by Plasma Concentration


Dosing regimens

Dosing Regimens


Pharmacology for anesthesia i

Can speed accumulation time by administering a loading dose


Routes of administration

Routes of Administration


Pharmacodynamics

Pharmacodynamics

  • What the drug does to the body

    • Typically receptor mediated


Pharmacology for anesthesia i

  • What factors affect the ability of a drug to interact with a receptor?

  • Drug size

    • Large enough to be specific

    • Not so large as to be unable to interact with the receptor

  • Drug Shape


Pharmacology for anesthesia i

  • Some drugs do not appear to fit into these categories

    • Osmotic agents

    • Transport regulators


Pharmacology for anesthesia i

Agonists

Antagonists

Competitive

Noncompetitive

Allosteric Activators

Potentiators


Pharmacology for anesthesia i

Partial agonists

Inverse agonists


Antagonists

Antagonists


Noncompetitive antagonist and spare receptors

Noncompetitive Antagonist and Spare Receptors


Full and partial agonists

Full and Partial Agonists


Cellular receptors

Cellular Receptors


Different drugs similar effects

Different Drugs Similar Effects

Potency vs. Efficacy


Population variation and therapeutic window

Population Variation and Therapeutic Window


  • Login