Anesthetics PDF
Document Details
Uploaded by ReadablePalmTree
Georgian College
Tags
Summary
This document provides an overview of different types of anesthetics, including barbiturates, non-barbituates, and inhalant anesthetics. It details their mechanisms of action, indications, and potential disadvantages, including cardiovascular and respiratory effects. The document also covers general information on anesthetics, such as metabolism and potential contraindications for specific patient populations.
Full Transcript
Anesthetics Barbiturates - Post synaptic enhancement of gaba - Binds GABA- a- receptors which increases chloride flow and depresses the central nervous system - Controlled substance - Indications - Anesthesia - Anticonvulsants - Sedation/ hypnosis - Anti-...
Anesthetics Barbiturates - Post synaptic enhancement of gaba - Binds GABA- a- receptors which increases chloride flow and depresses the central nervous system - Controlled substance - Indications - Anesthesia - Anticonvulsants - Sedation/ hypnosis - Anti-anxiety - Euthanasia - Disadvantages - Low therapeutic index - CV and resp depression - Perivascular necrosis - Ultra-short acting - Thiopental - Methohexital - Short-acting - Pentobarbital - Commonly used for euthanasia - Long acting - Phenobarrbital - Can be used for long term management as an anti-convulsant Non-barbituates Etomidate - Carboxylate imidazole derivative - Enhances GABA activity - Almost the ideal anesthetic - Minimla CV and resp depression - Disadvantages - Ultra-short acting - Muscle rigidity or twitching - Potential rough recovery Alfaxalone - Enhances gaba activity - IV, titrate to effects - Advantages - Rapid onset of action - Short duration and short recovery - Wide safety margin - Disadvantages - Apnea - Hypotension Propofol - Phenol derivative - Direct stimulation of Gaba receptors - IV titrate to effect - Short duration and rapid onset - Advantages - Minimal residual sedative effects - Rapid recovery - Disadvantages - Apnea - Hypotension - Short-shelf life - Pain on injection - Muscle twitching - Short duration Dissociative Ketamine - Phencycline derivative - NMDA antagonist - Peak action 1-2 min IV - Controlled - Nervous system activation - Reflexes are maintained - Muscle rigidity - Do not use in kidney compromised animals - Advantages - Short action - Increases HR and vasoconstriction - Cataleptic state - Has some analgesia - Disadvantages - No reversal - Apnea - Ocular effects Inhalant anesthesia General info Isoflourane - Rapid induction - Metabolized by lungs - Short recovery - Inexpensive - Vasodialation and hypotension - Resp depression - CV depression - No analgesia - May be contraindicated in head trauma as it can increase intracranial pressure Sevoflourane - Faster recovery then iso - Metabolized by liver - May be contraindicated in head trauma as it can increase intracranial pressure Nitrous oxide - AKA laughing gass - MAC sparing and a faster induction - Gravitates to gas filled compartments - Contraindicated in lung and GI compromised patients - When discontinued it will diffuse rapidly across the tissues back to the vessels before being released from the body through the lungs. - This causes oxygen to be become diluted in the body - Oxygen must be given for 5-10 minutes after discontinuing nitrous oxide - Exists in both a gaseous and liquid state. In order to know how much is left one needs to weight the canister.
