Download Free Medical Local anesthetics PowerPoint Presentation

Local anesthetics PowerPoint Presentation

DOWNLOAD MEDICAL POWERPOINT PRESENTATION

About This Presentation

Description : Check out this medical PowerPoint presentation titled "Local anesthetics".

This medical PowerPoint presentation talks about local anesthetics. Local anesthetics are drugs that produce temporary loss of sensation and pain in a specific area of the body without affecting consciousness. They work by blocking the transmission of nerve impulses from the site of application to the brain. Local anesthetics are commonly used in various medical and dental procedures, as well as in some cosmetic treatments.

There are two main types of local anesthetics: ester-type and amide-type. Ester-type local anesthetics, such as procaine and cocaine, are metabolized by plasma esterases and have a shorter duration of action. Amide-type local anesthetics, such as lidocaine and bupivacaine, are metabolized in the liver and have a longer duration of action.

Local anesthetics can be administered topically, as creams or gels applied to the skin or mucous membranes, or by injection directly into the affected area. They can also be given as a regional block, where the drug is injected near a cluster of nerves to numb a larger area of the body, such as an entire limb.

Tags : Local anesthetics, Ester-type local anesthetics, Amide-type local anesthetics, Anesthesiology

Published on : Mar 16, 2023 | Views : 682 | Downloads : 5

Shareable Url :

Embed Code :

Comment

Transcript

Slide 1-

Local anesthetics
Slide 2-

Objectives Recall how an action potential is generated and propagated Classify local anesthtics Describe the machanism of action, pharmacokinetics and toxic effects of local anesthetics Describe the different techniqes of use of LA Describe the risks and benefits of using vasoconstrictors with LA
Slide 3-

Overview Local anesthetics produce a transient and reversible loss of sensation (analgesia) in a circumscribed region of the body without loss of consciousness. Normally, the process is completely reversible.
Slide 4-

ppt slide no 4 content not found
Slide 5-

ANESTHETICS
Slide 6-

Local anesthetics - esters or amides a lipophilic aromatic group to a hydrophilic, ionizable amine. Most are weak bases
Slide 7-

Classification of LA Esters Benzocaine Procaine/ Proparacaine
Slide 8-

Classification of LA Amide Bupivacaine Levobupivacaine Lidocaine/Lignocaine Mepivacaine
Slide 9-

Ionized
Slide 10-

Local anesthetics gain access to the inner axonal membrane by traversing sodium channels while they are more often in an open configuration passage directly through the plasma membrane
Slide 11-

ppt slide no 11 content not found
Slide 12-

Block inititation and propagation of action potential
Slide 13-

ppt slide no 13 content not found
Slide 14-

Sympathetic block (vasodilatation) Loss of pain and temperature sensation Loss of proprioception Loss of touch and pressure sensation Loss of motor function Sequence of clinical anesthesia
Slide 15-

Potency = lipid solubility Higher solubility = can use a lower concentration and reduce potential for toxicity Anesthetic Potency
Slide 16-

DURATION OF ACTION Duration = protein binding Bupivacaine 95%Lidocaine 65%
Slide 17-

Pharmacokinetics Effective within 5 min Duration of action – 1-1.5 h Activity is Ph dependent Increased action in acidic ph
Slide 18-

ppt slide no 18 content not found
Slide 19-

CLEARANCE ESTERShydrolysis via cholinesterase AMIDESmetabolism via hepatic enzymes
Slide 20-

LA Infiltration anesthesia Regional anesthesia Surface anesthesia
Slide 21-

LA Infiltration anesthesia Regional anesthesia Surface anesthesia
Slide 22-

Gegional anaesthesia Nerve block Intravenous Extradural Intrathecal block/ spinal anaesthesia
Slide 23-

Nerve block Inject a drug around the nerve Anaesthetise a region
Slide 24-

Intravenous 0.5-1% lidocaine without adrenaline
Slide 25-

Extradural/epidural Thoracic, lumbar, sacral Act on nerve roots No hypotention
Slide 26-

ppt slide no 26 content not found
Slide 27-

Spinal anesthesia Sympathetic nerve block hypotension
Slide 28-

LA Infiltration anesthesia Regional anesthesia Surface anesthesia
Slide 29-

On intact skin – eutectic mixture of bases of prilocaine (EMLA) Slow absorption
Slide 30-

ppt slide no 30 content not found
Slide 31-

Prolongation of action Add vasoconstrictor – adrenaline Can use a larger dose Not to – fingers, toes, nose, penis
Slide 32-

ppt slide no 32 content not found
Slide 33-

Adverse effects LA’s cause some vasodilatation at site LA toxicity related to rate of absorption via blood flow
Slide 34-

Systemic Toxicity Blockage of voltaged-gated Na channel affects action potential propagation throughout the body Potential is present for systemic toxicity
Slide 35-

Effects of local anesthetics Excitation – anxiety, agitation, restlessness Convulsions Reduced myocardial contractility Vasodilatation