8) General Anesthetics Flashcards
What is the class for Nitrous Oxide
Inorganic gas
What is the mechanism for Nitrous Oxide
NMDA receptor antagonist
What are the therapeutics for Nitrous Oxide
Mask induction in children; adjuvant to volatile anesthetics, opioids
What are the important side effects for Nitrous Oxide
Post-operative nausea and vomiting; inactivates vitamin B (leading to abnormal embryonic development, abortion); accumulates in closed, air-containing spaces (bowel, middle ear, pneumothoraces, air emboli) because N2O insoluble in blood
What are the miscellaneous for Nitrous Oxide
No muscle relaxation
What is the class for Isoflurane (Forane)
Volatile anesthetic
What is the mechanism for Isoflurane (Forane)
Most potent
What are the therapeutics for Isoflurane (Forane)
Gold standard for maintenance of anesthesia
What are the important side effects for Isoflurane (Forane)
Pungent; dose dependent CNS depression, increase in cerebral blood flow and intracranial pressure; dose dependent decrease in systemic BP, decrease in respiratory function; relaxes skeletal muscle; increase in HR; malignant hyperthermia
What is the class for Desflurane (Suprane)
Volatile anesthetic
What is the mechanism for Desflurane (Suprane)
Least soluble, least potent (allows for rapid emergence from anesthesia)
What are the therapeutics for Desflurane (Suprane)
Maintenance of anesthesia
What are the important side effects for Desflurane (Suprane)
Most pungent (airway irritation symptoms); dose dependent CNS depression, increase in cerebral blood flow and intracranial pressure; dose dependent decrease in systemic BP, decrease in respiratory function; relaxes skeletal muscle; increase in HR; malignant hyperthermia
What is the class for Sevoflurane (Ultane)
Volatile anesthetic
What is the mechanism for Sevoflurane (Ultane)
Less soluble, less potent (but not irritating)
What are the therapeutics for Sevoflurane (Ultane)
Mask induction in children and adults; maintenance of anesthesia
What are the important side effects for Sevoflurane (Ultane)
Can form CO if not combined with CO2 correctly; dose dependent CNS depression, increase in cerebral blood flow and intracranial pressure; dose dependent decrease in systemic BP, decrease in respiratory function; relaxes skeletal muscle; malignant hyperthermia
What is the class for Methohexital (Brevital)
Barbiturates
What is the mechanism for Methohexital (Brevital)
GABAa receptor agonist, antagonist of NMDA-glutamate receptor; produce hypnosis & sedation, but is anti-analgesic
What are the therapeutics for Methohexital (Brevital)
Induce general anesthesia
What are the miscellaneous for Methohexital (Brevital)
Redistribute from brain to muscle and fat, metabolized by liver; dosed based on lean body mass
What is the class for Propofol (Diprivan)
Alkylphenol (a fatty acid)
What is the mechanism for Propofol (Diprivan)
GABAa receptor agonist, antagonist of NMDA-glutamate receptor; some a2 receptor activity; rapid onset and offset
What are the therapeutics for Propofol (Diprivan)
Anti-emetic at low doses; induction and maintenance of general anesthesia; sedation in ICU, procedural sedation
What are the important side effects for Propofol (Diprivan)
Propofol infusion syndrome: being given for several days leads to metabolic acidosis, rhabdomyolysis, heart & renal failure, lowering of BP, bradycardia, and death (likely due to fatty acid oxidation)
What are the other side effects for Propofol (Diprivan)
Painful injection site; supports bacterial growth
What are the miscellaneous for Propofol (Diprivan)
Administered IV in a lipid emulsion (cause of pain); be aware of allergies (egg and soy in emulsion); no malignant hyperthermia
What is the class for Etomidate (Amidate)
Carboxylated imidazole
What is the mechanism for Etomidate (Amidate)
GABAa receptor agonist (only D-isomer)
What are the therapeutics for Etomidate (Amidate)
Hypnosis; no analgesic activity
What are the important side effects for Etomidate (Amidate)
Pain on administration (due to solvent, propylene glycol); involuntary myoclonic movements due to subcortical disinhibition (not a seizure); post-operative nausea and vomiting; single dose inhibits cortisol synthesis
What are the miscellaneous for Etomidate (Amidate)
Minimal cardiorespiratory depression (good agent in patients with minimal cardiac reserve)
What is the class for Ketamine (Ketalar)
Phencyclidine
What is the mechanism for Ketamine (Ketalar)
NMDA receptor antagonist, kappa opiate agonist; leads to dose-dependent unconsciousness, amnesia, analgesia
What are the therapeutics for Ketamine (Ketalar)
Sedative/anesthetic for pediatric/developmentally delayed patients; induction in patients with reactive airway disease, hypovolemia (trauma patients), cardiac disease; with propofol for IV procedural sedation; adjuvant during and after surgery to reduce opiod use; part of multimodal pain therapy regimen; depression treatment
What are the important side effects for Ketamine (Ketalar)
Stimulates sympathetic nervous system outflow; increases cerebral blood flow, ICP; emergence delerium; nystagmus, lacrimation, salivation, and dissociative anesthesia
What are the miscellaneous for Ketamine (Ketalar)
Racemic mixture (S more potent); metabolized by P450 (norketamine, a third to a fifth as effective); great bronchodilator; contraindicated in CAD patients and those with with intracranial lesions
What is the class for Dexmedetomidine (Precedex)
a2 adrenergic agonist
What is the mechanism for Dexmedetomidine (Precedex)
Binds a2a and a2b in locus coeruleus and spinal cord (produces sedation, sympatholysis, and analgesia)
What are the therapeutics for Dexmedetomidine (Precedex)
Awake intubations, awake craniotomies; adjunct to general anesthesia in patients susceptible to narcotic-induced post-op respiratory depression; withdrawal/detoxification
What are the important side effects for Dexmedetomidine (Precedex)
Limited respiratory depression (wide safety margin)
What are the miscellaneous for Dexmedetomidine (Precedex)
Since GABA not hit, sedation is easier to wake from and is similar to non-REM sleep; FDA approved only for ventilation of ICU patients for under 24 hours
What is the class for Succinylcholine (Anectine)
Depolarizing NMB
What is the mechanism for Succinylcholine (Anectine)
Divalent ACh molecule; attaches to all ACh receptors, overstimulating them (first seen as disorganized muscular contractions (fasiculations), then paralysis)
What are the therapeutics for Succinylcholine (Anectine)
Skeletal muscle relaxant (intubation)
What are the important side effects for Succinylcholine (Anectine)
Malignant hyperthermia; cardiac dysrhythmias, hyperkalemia, increased intraocular pressure, increased intracranial pressure
What are the other side effects for Succinylcholine (Anectine)
Increased intragastric pressure, myalgias, masseter spasm
What are the miscellaneous for Succinylcholine (Anectine)
Hydrolyzed by pseudocholinesterase (in plasma); blockade cannot be reversed; only NMB with rapid onset and ultra-short duration of action
What is the class for Pancuronium (Pavulon)
Amino steroid non-depolarizing NMB
What is the mechanism for Pancuronium (Pavulon)
Competitive blockade of ACh (no depolarization); vagolytic
What are the therapeutics for Pancuronium (Pavulon)
Skeletal muscle relaxant; avoid in patients with renal insufficiency
What are the important side effects for Pancuronium (Pavulon)
Increase in HR
What are the miscellaneous for Pancuronium (Pavulon)
Only long acting non-depolarizing agent; supplied as liquid; 80% excreted unchanged in liver (low metabolism in liver); reverse with AChEI
What is the class for Vecuronium (Norcuron)
Amino steroid non-depolarizing NMB
What is the mechanism for Vecuronium (Norcuron)
Competitive blockade of ACh (no depolarization)
What are the therapeutics for Vecuronium (Norcuron)
Skeletal muscle relaxant
What are the important side effects for Vecuronium (Norcuron)
No cardiovascular effects
What are the miscellaneous for Vecuronium (Norcuron)
Intermediate acting; supplied as a powder (reconstitute); hepatic metabolism, hepatic and renal excretion; reverse with AChEI
What is the class for Rocuronium (Zemuron)
Amino steroid non-depolarizing NMB
What is the mechanism for Rocuronium (Zemuron)
Competitive blockade of ACh (no depolarization)
What are the therapeutics for Rocuronium (Zemuron)
Skeletal muscle relaxant (can substitute succinylcholine in rapid sequence intubation)
What are the important side effects for Rocuronium (Zemuron)
No cardiovascular effects
What are the miscellaneous for Rocuronium (Zemuron)
Intermediate acting; supplied as a liquid; hepatic metabolism, hepatic and renal excretion; can speed onset with higher dose; reverse with AChEI
What is the class for Sugammadex (Bridion)
Selective relaxant binding agent
What is the mechanism for Sugammadex (Bridion)
Complexes with rocuronium, rendering it inactive; no effect on AChesterase
What are the therapeutics for Sugammadex (Bridion)
Immediate reversal of rocuronium
What are the important side effects for Sugammadex (Bridion)
Decrease in blood presure, nausea and vomiting, dry mouth
What are the miscellaneous for Sugammadex (Bridion)
Not yet FDA approved
What is the class for Atracurium (Tracrium)
Isoquinoline non-depolarizing NMB
What is the mechanism for Atracurium (Tracrium)
Competitive blockade of ACh (no depolarization)
What are the therapeutics for Atracurium (Tracrium)
Skeletal muscle relaxant; use in patients with liver or renal dysfunction
What are the important side effects for Atracurium (Tracrium)
Histamine release (especially if given as rapid IV bolus), with resultant hypotension and tachycardia
What are the miscellaneous for Atracurium (Tracrium)
Undergoes spontaneous, non-enzymatic degradation (Hofman elimination); intermediate acting; reverse with AChEI
What is the class for Cis-atracurium (Nimbex)
Isoquinoline non-depolarizing NMB
What is the mechanism for Cis-atracurium (Nimbex)
Competitive blockade of ACh (no depolarization)
What are the therapeutics for Cis-atracurium (Nimbex)
Skeletal muscle relaxant; use in patients with liver or renal dysfunction
What are the important side effects for Cis-atracurium (Nimbex)
Unlike atracurium, no histamine release or downstream effects
What are the miscellaneous for Cis-atracurium (Nimbex)
Undergoes spontaneous, non-enzymatic degradation (Hofman elimination); intermediate acting; reverse with AChEI
What is the class for Edrophonium (Enlon)
AChE-I
What are the therapeutics for Edrophonium (Enlon)
Reversal of NMB
What are the miscellaneous for Edrophonium (Enlon)
Short-acting, fast onset
What is the class for Neostigmine (Prostigmin)
AChE-I
What are the therapeutics for Neostigmine (Prostigmin)
Reversal of NMB (most commonly used)
What are the miscellaneous for Neostigmine (Prostigmin)
More complete antagonism than edrophonium
What is the class for Pyridostigmine (Mestinon)
AChE-I
What are the therapeutics for Pyridostigmine (Mestinon)
Reversal of NMB
What are the miscellaneous for Pyridostigmine (Mestinon)
Longer duration of action than neostigmine, edrophonium
What is the class for Glycopyrrolate (Robinul)
Anti-muscarinic
What are the therapeutics for Glycopyrrolate (Robinul)
Reversal of neuromuscular blockade’s muscaranic effects
What are the important side effects for Glycopyrrolate (Robinul)
DUMBELLS
What are the miscellaneous for Glycopyrrolate (Robinul)
Could also use atropine
