14. Anesthesia Flashcards
Stages of anesthesia?
wc one does anesthesiologist minimize?
Stage 1: analgesia
Stage 2: Excitement (keep to minimum)
Stage 3: surgical anesthesia (regular respiration, eye movements cease, relx muscles)
Stage 4:medullary parlaysis
MOA of Benzos? Antagonist to tx OD?
Inc frequency of channel opening. Flumazenil
hw is cocaine metabolized? lidocaine?
cocaine = local ester anesthetic –> plasma esterases. Lidocaine = amide –> liver amidases
Drug used for epidural anesthesia?
Bupicacaine
wt determines duration of action of local anesthetics?
diffusion/absorption
local anesthetics: MOA? wc form has higher affinity?
Bind Na channel, inhibiting conduction.
Ionized have higher affinity.
Dissociate anesthetic used?
MOA?
wt reduces utility?
Ketamine
blocks NMDA receptor
Recovery has hallucinations
wc inhaled anesthetic does not cause malignant hyperthermia? 2 AEs? hw to prevent one?
Nitrous Oxide (N2O) megaloblastic anemia dec respiration –> administer 30% O2
wc local anesthetic causes vasoconstriction?
Cocaine only
3 Local anesthetic used in mucous membranes and cornea?
tetracaine, lidocaine and cocaine
How does solubility affect rate of induction of anesthetics?
Decreased solubility will increase rate of induction
inhaled anesthetic to use that does not induce arrhythmas, sensitize heart or decrease cardiac output?
Isoflurane
why are opioids used for anesthesia? wt type of procedures are they used for?
Analgesia
used in cardiac surgery
why Anticholinergics use for anesthesia? 2 used?
prevent secretions and prevent vagal effects.
Scopalamine - prevent salivaiton
Atropine – prevent reflex bradycardia
hw do the following affect inhalation anesthetic rate of induction, inc solubility in blood? inc concentration? inc alveolar ventilation? inc cardiac output?
inc solubility decreases rate of induction time inc concentration increases rate of induction inc alveolar ventilaiton increases ROI inc cardiac output decreases ROI
Inhaled anestheric that produces toxic compound A? other thing released by drug?
Sevoflurane. also releases Fl
Effect of vasoconstrictors on local anesthesia?
2 vasoconstrictors?
2 MOA?
Benefit?
when to not use?
Prolong local anesthesia
Epinephrine, phenylephrine
slow absorption and dec drug plasma concentration
less side effects
dont use in end areteries (fingers toes
why do local anesthetics cause hypersensitivity rxns?
ester anesthetics get into systemic circulation and are metbaolized to PABA
wt is infiltration anesthesia?
use?
wt double duration?
injected into tissues
dental procedues
epinephrine doubles duration
Local anesthetic used on skin?
Benzocaine
wt is second gas effect? drug often used?
when a rapidly absorbed gas increases the rate of uptake of a 2nd gas. NO used
Propofol:
Use?
Advantage?
Major AE? pt populaiton w more pronounced AE?
Drug increasing AE?
Drug causing serious effects in pediatric patients?
Drug precipitating seizures?
Induction and maintenance of anesthesia.
Rapid Recovery.
CV effects AE. (more in elderly)
Opiates increase AE and sedation.
Fentanyl causes serious bradycardia in peds.
Alfentanil –> seizures.
age MAC is calculated? effect of infancy on MAC? old age? hyperthyroidism? hypothyroidism? sedatives? amphetamines? red hair?
35-40 y/o infancy - inc old age - dec hyperthyroidism - inc hypothyroidism - dec sedatives - dec amphetamines - inc red hair - inc
?name of barbiturate we need to know? What causes recovery? contraindication?
Thiopental.
Recovery is due to redistribution from the brain into less vascular regions (skin and muscle)
CI: Porphyria
wc anesthetic is actually a weak anesthetic but a strong analgesia?
Nitrous Oxide
df MAC?
Minimum alveolar concentration – inspired concentration of anesthetic producing anesthesia in 1/2 of subjects
wc anesthetics are in LET mixture
Lidocaine
Epinephrine
Tetracaine
