Anesthetics

5 features of full anesthesia
	
	reversible unconsciousness
	hypnosis
	amnesia
	analgesia
	immobility

4 stages of anesthesia
	
	I: analgesia
	II: delirium (try to avoid, one sign of this stage is disconjugate gaze)
	III: surgical anesthesia
	IV: medullary depression (incl respiratory depression)

5 ways to speed induction (i.e. inc rate of FA/FI)
	
	1. Inc inspired anesthetic conc (inc FI)
	2. Inc ventilation frequency and amount
	3. Dec solubility of anesthetic gas
	4. Dec pulmonary blood flow
	5. Inc alveolar-venous partial pressure gradient

3 ways to speed elimination
	
	Dec inspired anesthetic conc (turn it off)
	Inc ventilation
	Dec solubility

Targets of non-NO anesthetics
	
	Enhance GABA and Glycine receptor
	Decrease NMDA, AMPA, nicotinic ACh receptors

Malignant hyperthermia
	
	The only anesthetic disease
	AD activating mutation in ryanodine receptor (RYR1) -> excessive mm activity
	Sx: mm rigidity, inc temp, inc HR, inc pCO2, dec pH, rhabdomyolysis
	Rx w/ dantrolene

Halothane
	
	Alkane gaseous anesthetic
	Most potent, but slow onset
	Not used often in US
	PK: liver metabolism into trifluoroacetic acid (can cause autoimmune hepatitis)

Isoflurane
	
	Ether gaseous anesthetic
	Medium potency and medium onset

Sevoflurane
	
	Ether gaseous anesthetic
	Medium potency and rapid onset

Desflurane
	
	Ether gaseous anesthetic
	Low potency and rapid onset

Nitrous oxide
	
	Inhibits NMDA-R -> dec postsynpatic transmission
	Incomplete gaseous anesthetic (can't give hypoxic mixture of NO + O2!)

Thiopental
	
	MOA: IV GABA-A-R agonist
	Also anticonvulsant, dec brain swelling
	Tox: cardiorespiratory depression upon anesthesia

Propofol
	
	MOA: IV GABA-A-R agonist
	Tox: mild cardiorespiratory depression, burning sensation upon rapid IV

Etomidate
	
	MOA: IV GABA-A-R agonist
	Tox: adrenal depression (don't infuse continuously), no cardiorespiratory depression

Ketamine
	
	MOA: IV NMDA blocker
	Cutaneous analgesia -> Rx burn patients
	Tox: symp stimulator (inc HR, inc BP, inc CBF, bronchodilation)