Dissociative anesthetics/barbiturates/non-barbiturates Flashcards
What is general anesthesia?
a drug induced CNS depression resulting in unconsciousness in which the patient cannot be aroused by painful stimuli, and sensory, motor, and autonomic reflex functions are attenuated.
What is dissociative anesthesia?
drug induced dissociation of the thalamocortical and limbic systems resulting in a catatonic state. Sensory input is dissociated from perception.
What is the MOA for dissociative anesthetics?
non-competitive NMDA receptor antagonist. It inhibits activation by glutamate of ligand gated ion channels.
NMDA antagonists affect what pathway of nociception?
modulation
Why do you have to be cautious with dissociative anesthetics in cats?
because they have the most renal excretion
How long does recovery from dissociative anesthetics take?
2-10 hours.
What are the CNS effects of dissociative anesthetics?
there’s a dual effect of depression of the thalamocortical system and activation of the limbic system which leads to dissociation. Catalepsy is also seen, and pharyngeal and laryngeal reflexes are maintained. Can see somatic analgesia at sub-anesthetic doses
T/F: you can give ketamine on its own as an anesthetic agent.
False
T/F: dissociative anesthetics cause myocardial depression.
True. However, net effect is CV stimulation
Why are dissociative anesthetics not recommended for craniotomy or ocular surgery?
Because they increase intracranial and intraocular pressure.
Why are dissociative anesthetics good for asthmatic patients?
they cause bronchodilation.
T/F: dissociative anesthetics can cause respiratory depression at large doses
True
This drug is a schedule III non-narcotic controlled drug that should not be used alone as an analgesic, but is known to have opioid-sparing capabilities when used at sub-anesthetic doses with opioids
Ketamine
What 3 drugs when used together to induce anesthesia are known as “kitty magic”?
ketamine + buprenorphine + dexmedetomidine
What does the triple dip in large animals consist of? What is it a form of?
guaifenesin + xylazene + ketamine. It is a form of total intravenous anesthesia
T/F: ketamine can serve as an anti-inflammatory
True
Why should you lubricate eyes when using ketamine?
because eyes remain open and the blink reflex may be delayed for hours