Br Pharmacology: General Anesthetics

Front 1

What are the stages of anesthesia?

Back 1

1) analgesia
2) disinhibition
3) surgical anesthesia
4) medullary depression

Front 2

Analgesia is what what stage? What occurs?

Back 2

1) Stage I
2) decreased awareness of pain
3) consciousness impaired but not lost

Front 3

Disinhibition is what stage? What occurs?

Back 3

1) Stage II
2) delerious and excited
3) amensia, enhanced reflexes, and irregular respirations
4) may have retching and incontinence

Front 4

Surgical anesthesia is what stage? What occurs?

Back 4

1) Stage III
2) unconscious and no pain reflexes
3) regular respirations and BP

Front 5

Medullary depression is what stage? What occurs?

Back 5

1) stage IV
2) severe respiratory and cardiovascular depression

Front 6

What is the general feature of how CNS depressants work?

Back 6

increase threshold for neuronal firing

Front 7

What is the MOA of inhaled anesthetics, barbituates, benzos, etomidate, and propofol?

Back 7

facilitate GABA mediated inhibition of GABA-A receptors

Front 8

What is the MOA of ketamine?

Back 8

Glutamate antagonist at NMDA receptors

Front 9

inhaled anesthetics have 2 MOAs, what are they?

Back 9

1) GABA-A agonist
2) nicotinic ACh receptor inhibitor

Front 10

Are pain receptors or neurons in the reticular formation inhibited first?

Back 10

pain receptors

Front 11

What are examples of the inhaled anesthetics?

Back 11

1) NO
2) halothane
3) desflurane
4) enflurane
5) isoflurane
6) sevoflurane
7) methoxyflurane

Front 12

What does it mean if a drug has a low blood:gas coefficient? What is an example of low and high?

Back 12

1) low means that the drug equilibrates more rapidly in blood
2) low = NO, desflurane, sevoflurane
high = halothane

Front 13

What happens to the partial pressure of gas as the pulmonary blood flow increases?

Back 13

the partial pressure rises at a slower rate resulting in a slower onset of anesthesia. At low flow rates the onset is faster

Front 14

If a drug has a low blood:gas coefficient is there a quicker or slower recovery?

Back 14

quicker because of low solubility

Front 15

How is the potency of an inhaled anesthetic measured?

Back 15

the minimum alveolar concentration (MAC) is the alveolar concentration required to eliminate the response to a standardized painful stimulus in 50% of patients

Front 16

What are the CNS effects of inhaled anesthetics?

Back 16

1) decrease brain metabolic rate
2) decrease vascular resistance and increase blood flow

Front 17

What effect is unique to enflurane?

Back 17

muscle twitching

Front 18

What are the cardiovascular effects of inhaled anesthetics?

Back 18

1) decrease BP
a. Enflurane and halothane cause myocardial depression
b. isoflurane, desflurane, and sevoflurane cause peripheral dilation
2) NO does not have large effects on BP

Front 19

NO has a low anesthetic potency but a high___?

Back 19

minimum alveolar concentration (MAC)

Front 20

What are the respiratory effects of inhaled anesthetics?

Back 20

1) increased rate
2) decreased tidal volume with increased arterial CO2 tension
3) decrease ventilatory response to hypoxia
4) NO has little effect
5) bronchodilators

Front 21

Which inhaled anesthetic is a pulmonary irritant? Which has a pungency that reduces a patients ability to hold it in?

Back 21

1) desflurane
2) enflurane

Front 22

What are some toxic effects of halothane?

Back 22

1) post-op hepatitis in patients with hypovolemic shock or severe stress

Front 23

What element can increase the metabolism of methoxyflurane?

Back 23

floride and lead to renal insufficiency after prolonged anesthesia

Front 24

What enzyme does NO decrease and what is the result?

Back 24

1) methionine synthase
2) leads to megaloblastic anemia

Front 25

How can malignant hyperthermia result when using inhaled anesthetics?

Back 25

if the patient is also taking neuromuscular blockers like succinylcholine

Front 26

What is the pathogenesis of malignant hyperthermia?

Back 26

1) RyR1 or L-type Ca2+ channels are mutated in skeletal muscle
2) results in uncontrolled release of Ca2+ leading to muscle spasm, hyperthermia and autonomic lability

Front 27

What is the treatment for malignant hyperthermia?

Back 27

dantrolene

Front 28

Which barbituates are used for anesthesia? When are they used?

Back 28

1) thiopental
2) methohexital
3) used in short surgical procedures

Front 29

What are some of the toxicities of barbituates?

Back 29

1) respiratory and circulatory depressants
2) decreased ICP from decreased cerebral blood flow

Front 30

Which benzos are used as anesthetics?

Back 30

midazolam

Front 31

Cases of severe post-op respiratory depression have occurred with midazolam. What drug could be given to accelerate recovery?

Back 31

flumazenil

Front 32

Which drug produces a state of dissociative anesthesia? What does this mean?

Back 32

1) ketamine
2) patient is conscious but is catatonic, analgesic and has amnesia

Front 33

Ketamine is related to what street drug?

Back 33

PCP

Front 34

What are toxicities of ketamine?

Back 34

1) increased ICP from increased BP
2) disorientation, excitation and hallucinations during recovery
3) reduce symptoms with a benzo

Front 35

definition of pvs (persistent vegetative state)

Back 35

pt has lost all awareness and cognitive fxn, but remain wiht eyes open, have sleep-wake cycles, and maintain respiration and other autonomic fxn

Front 36

What are side effects of opioids?

Back 36

1) chest rigidity
2) neuroleptanesthesia- state of analgesia and amnesia when fentanyl is used with droperidol and NO

Front 37

toxicities with opioid anesthetics can be treated with what?

Back 37

naloxone - competitive antagonist of mu receptors in CNS

Front 38

What are the actions of propofol?

Back 38

1) antiemetic
2) anesthetic in outpatient treatment
3) prolonged sedation in critical care settings

Front 39

What are side effects of propofol?

Back 39

hypotension through decreased peripheral resistance

Front 40

What is etomidate used for?

Back 40

1) rapid induction with minimal change in respiratory rate
Note: has a short duration of action
2) no analgesic properties

Front 41

putting someone under general anesthesia that has limited cardiac and respiratory reserve should be done with what drug?

Back 41

etomidate

Front 42

What are side effects of etomidate?

Back 42

1) pain
2) MYOCLONUS
3) nausea
4) prolonged causes adrenal suppression

Front 43

Inversely related to potency of anesthetics

Back 43

Minimum alveolar anesthetic concentration (MAC)

Front 44

Inhaled anesthetics metabolized by liver enzymes which has a major role in the toxicity of these agents

Back 44

Halothane and methoxyflurane

Front 45

What limits are listed on the Daily, and what are they?

Back 45

O2-1600
P3 Tires- Nose-150lbs Main-170lbs
EP-3 Tires- Nose-170lbs Mian-190lbs
Hyd systems- 1-5.6 2-1.0
EBB-1900
Brake accum-800 +/-25
EDC-Full

Front 46

Inhaled anesthetics are myocardial depressants

Back 46

Enflurane and halothane

Front 47

Inhaled anesthetic causes peripheral vasodilation

Back 47

Isoflurane

Front 48

Inhaled anesthetic that may sensitize the myocardium to arrhythmogenic effects of catecholamines and has produced hepatitis

Back 48

Halothane

Front 49

Inhaled anesthetic, less likely to lower blood pressure than other agents, and has the smallest effect on respiration

Back 49

Nitrous oxide

Front 50

Opioid associated with respiratory depression, but is used in high risk patients who may not survive full general anesthetia

Back 50

Fentanyl

Front 51

State of analgesia and amnesia produced when fentanyl is used with droperidol and nitrous oxide

Back 51

Neuroleptanesthesia