Anesthesia Drugs Flashcards
Inhaled Anesthetics
Desflurane, halothane, enflurane, isoflurane, methoxyflurane + N2O
Depression of cardio/resp but INC cerebral flow
Malig hyperthermia
Thiopental
IV barbiturate - high potency (high lipid solubility) and quick entry into brain so used for induction (SHORT procedures)
Dec cerebral flow
Ketamine
PCP analog - blocks NMDA receptors (dissociative anesthetic)
Inc cardio, disorientation, hallucination, unpleasant dreams and inc cerebral flow
Propofol
Similar to thiopental but less post-op nausea
Opioids
Morphine and fentanyl for general anesthesia
Local Anesthetics (2 classes)
Esters - procaine, cocaine, tetracaine, benzocaine
Amides - lidocaine, mepivacaine, bupivacaine (all have 2 I’s)
Block Na channels from inner portion of the channel (esp rapidly firing neurons)
Order of Local Anesthetic Nerve Block
Small myelinated, small unmyelinated, large myelinated, large unmyelinated
Pain –> temp –> touch –> pressure
How to enhance local-ness of local anesthetic?
Give w/ vasoconstrictor (epi) so less bleeding and less systemic spread
Local anesthetics in acidic/infected tissue
Alkaline anesthetics become charged in presence of acidic tissue so they cannot cross membrane effectively so MUST GIVE HIGHER DOSE
Depolarizing Neuromuscular Block
Succinylcholine - strong Ach receptor agonist –> sustained depolarization so NO muscle contraction
Phase 1 - prolonged depolarization; no antidote
Phase 2 - repolarized but de-sensitized; Ach receptors now available but de-sensitized; can overcome w/ AchE inhibitor
Non-Depolarizing Neuromuscular Block
Tubocurarine, atracurium, mivacurium, pancuronium, rocuronium
Comp antagonists w/ Ach receptor
Reverse w/ neostigmine or edrophonium to inc Ach (but give atropine too to prevent muscarinic effects)
What is the treatment for malignant hyperthermia?
DANTROLENE
Prevents release of Ca++ from SR by binding ryanodine receptors
Malignant hyperthermia caused by inc Ca++ release from SR (likely due to auto dom mutation in ryanodine receptor)
