Flashcards in Required Reading-Drugs Deck (58):
IV induction agents
propofol, etomidate, ketamine, thiopental
fentanyl, morphine, hydromorphone, remifentanil
General anesthetics will ensure that pt is _____ and ____ throughout the procedure.
____ and ___ nerve blocks deliver drugs to precise locations along neural transmission pathways; ___ drugs are usually used.
Neuraxial (spinal/epidural); peripheral; local anesthetic
Benzodiazepines have ___, ___ and ___ effects due to GABA transmission enhancement. Benefit is ______ therapy.
sedative; anxiolytic; amnesic; anticonvulsant
Midazolam (Versed)–IV sedative dose ___; effects last 20-30 min due to ______
1-2 mg; redistribution
Benzos do NOT provide ___ effects.
Monitored anesthesia care [MAC]/general anesthesia can be replaced by ____ to provide sedation/amnesia in OR. This is particularly useful in patients with poor _____ status who may not tolerate enough inhaled agents to be unconscious.
Tx for oversedation due to benzos; only lasts about ____, which is particularly a problem with long-lasting benzos (re-sedation), like ____.
flumazenil (Romazicon); diazepam (t1/2 about 20hrs)
Opioids have ___ and ___ (not reliable) effects; bind receptors in ___ of brain and ___ of SC.
sedative; analgesic; periacqueductal gray; substantia gelatinosa
Opioid binding R cause inhibition of _____ and ____ release.
ACh; substance P
Analgesia– short-acting opioids, like ____, are used for pain control ____; long-acting opioids used for _____ pain control.
fentanyl; intraoperatively; postop (morphine, hydromorphone, meperidine)
Fentanyl– rapid-acting opioid; given during ___ of anesthesia to blunt sympathetic response during ____. Neg effects: can cause ___ in high doses
induction; intubation; apparent chest wall rigidity (>1000mcg; may impair adequate ventilation)
Sufentanil– rapid-acting opioid used for ____ and ____
Alfentanil– ULTRA rapid-acting opioid (5-10 min); about ___ as potent as fentanyl but with ___ onset; used for ___ and ___
25%; fast (1-2 min); induction; maintenance
Morphine– long-acting (peak onset 30 min) opioid; ___-soluble and can accumulate in the presence of _____, causing bradycardia and ___ release
lipid; renal failure; histamine; [typical dose postop 5-15mg]
Hydromorphone– long-acting (peak 15-30min) opioid; MC used for ___ pain control
postop [typical dose 1-2mg]
Meperidine–must be metabolized to normeperidine; has ___ properties (postop use); can accumulate in pts w/ ____ leading to oversedation or ___ and histamine release. Should be avoided in pts on ______.
anti-shivering; renal failure; seizures; type A MAOIs [serotonin-like syndrome hyperthermia, seizures, death]
Remifentanil–ULTRA short-acting (t/12 ~___min) b/c broken down by nonspecific ____, so does not ____ in patients with renal/hepatic failure; good for short intraop cases (~2hrs)
4; plasma esterases; accumulate
Accumulating opioids (___> alfentanil/sufentanil > ____) the context-sensitive half-time increases w/ long durations of administration
Main adverse effect of opioids is respiratory depression due to a decrease in _____ and an increase in the _____.
hypoxic drive; apneic threshold [CO2 level above which patients are stimulated to breathe]
To reverse opioids, use ____, which antagonizes ___ receptors.
Methylnaltrexone, opioid antagonist like naltrexone, can block peripheral receptors located in the ____ without affecting analgesia.
Because of blunting of endocrine response, opioids can decrease ____ with minimal effects on baseline ___ status. Good for OR pt w/ ____.
stress response; CV; hemodynamic instability
Any IV med that causes a patient to be unconscious is considered an _____; benzos and opioids are MC used together
Propofol– enhances ____ receptor; IV rapid-onset (t/12 ___ min) and short DOA due to rapid ___ metabolism and excretion by ___.
GABA-A; 2-8; hepatic; kidneys [**few pharmacokinetic changes w/ pts w/ liver or renal dz!!]
Propofol is ___philic and provides ___ for gen anesthesia. A common SE is __ after an induction dose.
lipo; sedation; apnea
Propofol is a potent __ and __ depressant and therefore is avoided when pts need to maintain spontaneous ventilation, are hypotensive or unable to sustain ____ stability.
CV; respiratory; hemodynamic
Favorable SEs of propofol include anti___ and anti___ properties. MC SEs is pain on injection, for which ___ is added.
pruritic; emetic; lidocaine
Thiopental– __ drug class; rapid onset; CV and respiratory depression; most use for effect of prolonged _____
barbiturate; cognitive disarray
Thiopental is used in ____ sx cases because it is cerebro-protective
Main problem with thiopental is that because it is ____, it can precipitate and occlude catheters if mixed with _____.
alkaline; paralytic agents (acidic)
Thiopental induces the enzyme _____ and therefore is contraindicated in pt w/ inducible porphyrias
ALAS [RLS in prophyrin synthesis]
Thiopental may result in delayed effects due to high ____ and low _____
protein binding; hepatic excretion ratio
Etomidate– ___ drug class [inc GABA transmission]; unlike propofol/thiopental, has MINIMAL ___ and ____.
imidazole; CV depression; respiratory depression [Therefore it is safer in hemodynamically unstable pts]
Etomidate is used in these three patient populations:
(1) elderly (2) trauma patients (3) severely volume depleted/on vasopressors
After a single bolus, the clinical effect of etomidate is terminated by ____ and rapid _____.
redistribution; hepatic metabolism
A SE of transient _____ after etomidate is due to enzyme inhibition; therefore try not to use with ___ drugs or those with ______. MC SE is myoclonus and postop ___ and ___.
adrenal suppression; steroid; adrenal insufficiency; nausea; vomiting
Ketamine– acts as antagonist at ____ R; SEs are ____, like those due to PCP [related], ___ and increase in ICP
NMDA; hallucinatory; salivation
Ketamine is the ONLY ___ stimulant because it inhibits NE reuptake and has minimal effect on respiratory drive; also a potent ___ and ____
CV; analgesic; bronchodilator
Ketamine is used in these two patient populations
(1) trauma [sedation, analgesia, amnesia, CV support] (2) pediatrics [hallucinations not as scary]
Ketamine is AVOIDED in these two pt populations
(1) cardiac issues [arrhythmias, HTN] (2) where pt is going to emerge from anesthesia soon after admin [short cases]
NMBs are used to facilitate ____. Adequacy of relaxation can be determined by use of a _____.
intubation; nerve stimulator
Succinylcholine– depolarizing NMBs; prevents junctional ____ b/c drug isn't hydrolyzed by true AChE; used almost exclusively for ______
Succinylcholine has quick onset ___ seconds and duration ___ min; if repeated doses are administered, ___ blockade may occur leading to a slow recovery
30-45; five; phase II [prolonged end-plate depol leads to conformational changes w/in AChR]
___ is the enzyme that breaks down succinylcholine; some pple have a partial/total deficiency and thus can experience prolonged paralysis: ___ min for hetero and ___ hrs for homozygotes
Pseudocholinesterase; 20-30; 6-8
SE of succinylcholine is elevation in ____ after admin. Must be used in caution with ___ patients or those with ___ or ___ injury.
potassium; burn; denervation; muscle
SEs of note are succinylcholine are bradycardia and ______
Nondepolarizing NMBs are AChR antagonists that inhibit junctional _____; they are divided into benzylisoquinoliniums (______) and steroidals (______, _____ and ______)
depolarization; cisatracurium; rocuronium, vecuronium, pancuronium
Onset time and duration of action of nondepol NMBs are: ____ > _____ > _____ > _____
pancuronium; cisatracurium; vecuronium; rocuronium
___ is simultaneously administered with neostigmine to prevent muscarinic overactivity [bradycardia, asytole, bronchospasm] when reversing NMB agents.
Glycopyrrolate [also atropine]
____ is a NMB is that is degraded in the plasma and is used when there is severe renal/hepatic dysfunction.
Cholinergic crisis post-tx neostigmine consists of these symptoms:
bradycardia, bronchospasm, emesis, miosis, muscle weakness
Neostigmine and glycopyrrolate [paired] have a ___ onset and ___ duration compared to edrophonium and atropine [paired]
Central anticholinergic syndrome is due to atropine [unlike ___] overdose because it crosses the _____. Symptoms include ____. Treat with physostigmine.
glycopyrrolate; BBB; delirium, excitation, fever, flushing, tachycardia
Complete anesthesia includes ___, ____ and ____.
hypnosis [sedative], analgesia [opioids], muscle relaxation
Which opioids would be best to use for 1.5hr case? Postop?
sufentanil, alfentanil, remifentanil (need relatively flat context-sensitive half time curves); fentanyl, morphine, hydromorphone