drugs Flashcards
relief of pain w/out intentional production of altered mental state
analgesia
decreased apprehension with no change in level of awareness
anxiolysis
protective reflexes maintained. independent maintenance of airway/O2 sat/ventilation. REsponse to physical and verbal stimulation
conscious sedation
profound effects with loss of one or more of following: protective reflexes maintained. independent maintenace of airway/O2 sat/ventilation. response to verbal stimulation
deep or unconscious sedation
sensory, mental, reflex and motor blockade; concurrent loss of ALL protective reflexes
general anesthesia
why are INHALATIONAL AND INTRAVENOUS dosing preferred?
b/c they offer more immdeiate control over dose and hence duration of action
agenst capable of producing reversible depression of neuronal function, producing loss of ability to perceive pain and/or other sensations
general anesthetics (maintain patent airway–(may require Positive pressure ventilation)
unconsiouscness = loss or protective reflex. need to maintain airway
describes what: anesthetic activity = linked to lipid solubility. more lipid soluble = higher anesthetic activity.
what is the execption?
Myer-Overton hypothesis
Exception: can make drug more lipid soluble, but then you lose anestehtic property of drug. NOTE: N20 has really low oil: gas partition coefficient. (greatest to least Isoflurane >sevoflurane>desflurane)
concentration of inspired gas needed to render 50% pt unconsicous
minimum alveolar concentration.
the lower the MAC the ____
more potent the anesthetic.
lipid solubility described by what coeff
oil:gas coefficicent. larger # = more lipid soluble drug
inhaled anesthetics MOA:
what do they enforce:
what do they inhibit:
reinforcement of : GABAa and glycine inhibitory signaling, and two pore K+ channel
inhibition of glutamatergic signalling
during anesthesia –> decreased parietal response. therefore anesthesia decreases coritcal interactions and decreases integration.
note: anesthetic agents distribute throughout body including PERIPHERAL NEURONS : OVERALL effet of drug includes: NOT ONLY direct effect on CNS, but also modulation of ASCENDING NEURAL pathways to the CNS and DESCENDING pathway to peripheral tissue
t/f. loss of memory and perceptive awareness can precede production of analgesia
true
blood gas partition coefficiecnt
how much anestheic needs to be accumulated in blood to reach equillibrium with avelovlar concentration (partial pressure in admixiure administed = partial pressure in systemic circulation)
which new inhalational anesthetics equillbribate most rapidly
sevoflurane
desflurane (much quicker than halothane at 2.3x)
why is MAC of nitrous oxide 105%
Nitrous oxide = incomplete anesthetic (would need to increase, increse, hyperbaric pressure for this agent to work ell)
do you want a high or low Blood:gas partition coefficient in order to achieve anesthethia the most quickly
very low coefficient.
why does nitrous oxide reach saturation in blood rapidly?
b/c it is not lipophilic and does not get stuck in fat
t/f. delivery of anesthetic to blood can be hastened by increasing ventilation rate? which drugs affected?
True. increased ventilation leads to the rapid equillibration of NITROUS OXIDE.
what are the 4 respiratory effects of inhaled anesthetics?
- increaesed RR
- decreased tidal volume
- regular rhythmic shallow breathing
4. reflex response to PaCO2 blocked by all except N2O
which inhaled anesthetic does not have cardio effects unless w/an opioid
Nitrous oxide
4 ADE cardio for inhaled anesthetics
- decreased sympathetic outflow( direct depression)
- decrease adrenal catecholamine release( peripheral ganglionic blockade)
- decrease CA2+ flux(baroreceptor decrease)
- Vagal stimulation
why do we use nitrous oxide?
vapor sparing effects
reduced inspired volatile concentration
mild analgesic properties
what is a drug combo that produces pain relief and produces analgesia
nuerolept analgesia use fentanyl (short acting opiate. recal fentanyl patch).
droperidol + fentanyl = neurolept-analgesia. combined in preparation. useful for radiology, endoscopy, burn dressings.
Add N20 = nuerolept-anesthesia. Atropine + morphine or mereprinie
why would you add atropine to neurolept analgesia regiment?
to dry out secretions
for a quick 20 minute procedure, which analgesic which would you use? does it cause N/V?
FENTANYL!!!!
more lipid soluble, onset in <30 seconds, peak effect in 2-3 minutes, and N/V RARE. (COMPARE that to MORPHINE!!!!)
for long-lasting analgesia, which drug do you want to use?
MORPHINE!!!
- poor penetration of BBB
pain relief correlates with CSF drug levels.
