General Anesthetics I and II

Question 1

Characteristics of General Anesthesia?

Answer 1

Hypnosis, amnesia, analgesia, muscle relaxation, attenuation of autonomic reflexes

Question 2

Is there one anatomic site responsible for producing general anesthesia?

Answer 2

No, but certain anesthetic effects can be attributed to certain locations.

Question 3

Theory for how unconsciousness is produced?

Answer 3

Depression of thalamic neurons and blocking thalamo-cortical communication.

Question 4

Where is immobility in response to noxious stimuli mediated?

Answer 4

Spinal Cord

Question 5

Likely mechanisms of anesthetic drugs?

Answer 5

Inhibit excitatory and enhance inhibitory synaptic transmission.

Question 6

Volatile anesthetics effects on Glutamate and GABA?

Answer 6

Glutamate- inhibit release

GABA- both increased and decreased release

Question 7

Post-synaptic effects of anesthetics?

Answer 7

variable effects on EXCITATORY NTs receptors

enhance receptor response to INHIBITORY NTs

Question 8

Volatile anesthetic effects on Na+ channels

Answer 8

Inhibit activity, reduce nt release at synapse

Question 9

Neurotransmitters serve as what in ligand-gated ion channels?

Answer 9

Ligands, mediate fast excitatory or inhibitory neurotransmission

Question 10

3 categories of Glutamate ion channels

Answer 10

NMDA (modulate long term synaptic response)

AMPA, Kainate (involve fast excitatory transmission)

Question 11

Drug effects on GABAa receptors at clinical concentrations and high concentrations

Answer 11

Clinical: increase Cl current produced by low GABA
High:
1) Direct gating ability to activate receptor w/o GABA
2) Prevention of GABA from initiating Cl current

Question 12

Barbitiuate, Propofol and Volatile anesthetics effect on GABAa receptor?

Answer 12

Create conformational change in GABAa receptor to increase affinity for GABA

Question 13

Where do anesthetics likely bind?

Answer 13

Hydrophobic pockets on proteins

Question 14

What must be used in conjunction with anesthetics in order to conduct surgery?

Answer 14

Opioids or Neuromuscular blocking agents to produce analgesia or muscle relaxation.

Question 15

How are inhaled anesthetics delivered?

Answer 15

By agent specific vaporizers attached to anesthesia machine.

Question 16

Equilibration implies what for anesthetic gas in twophases (ie alveoli and blood, blood and brain)

Answer 16

same partial pressures in both phases (does not mean they have same concentration)

Question 17

What is MAC?

Answer 17

Age dependent concentration of an inhaled anesthetic at which 50% of patients will not move.

Additive when 2 agents given together

Question 18

What propels anesthetics to brain?

Answer 18

partial pressure gradients

P (Alv), Pa, P(brain)

Question 19

In comparison to the other volatile anesthetics what is different about Desflurane?

Answer 19

has a low bp, low potency, least soluble

Question 20

MOA of Nitrous Oxide?

Answer 20

NMDA receptor antagonist

Question 21

Use of N2O?

Answer 21

mask induction in children (no smell, can flavor)

Question 22

SE of N2O?

Answer 22

Post-surgical N/V
adverse effects on embryonic development
accumulates in closed air spaces (bowel, middle ear, pneumothorax, air emboli)

Question 23

Name three volatile anesthetics

Answer 23

Isoflurane, Desflurane, Sevoflurane

Question 24

What is Isoflurane used for?

Answer 24

Gold Std of anesthesia maintenance

Question 25

SE of isoflurane, desflurane, and sevoflurane?

Answer 25

Dose Dependent CNS depression Increased cerebral blood flow, ICP DD decrease in BP, resp fx, relaxes skeletal muscle Increase in HR, malignant hyperthermia

Question 26

What volatile anesthetic is the most pungent?

Answer 26

Desflurane

Question 27

MOA of methohexital?

Answer 27

GABAa receptor binding; produce hypnosis/ sedation | NMDA glutamate receptor antagonist

Question 28

MOA of propofol?

Answer 28

GABAa receptor agonist, antagonist of NMDA- glutamate receptor

Question 29

Use of propofol?

Answer 29

induction/ maintenance of general anesthesia

Question 30

SE of propofol?

Answer 30

Propofol infusion syndrome (seen in pts given for several days) Metabolic acidosis, myocardial failure, rhabodomyolysis, hyperkalemia, renal failure

Question 31

MOA of etomidate?

Answer 31

GABAa receptor agonist

Question 32

Use of etomidate?

Answer 32

Hypnosis; no analgesia | good for pts w/ minimal cardiac reserve

Question 33

SE of etomidate?

Answer 33

involuntary myoclonic movements post-op N/V single dose inhibits cortisol synthesis

Question 34

MOA of ketamine?

Answer 34

NMDA receptor antagonist kappa opiate agonist DD unconsciousness, amnesia, analgesia

Question 35

SE of ketamine?

Answer 35

Stim sympathetics Increased Cerebral blood flow--> ICP emergence delirium, salivation, lacrimation, nystagmus

Question 36

Ketamine treats?

Answer 36

sedative anethestic- children or Developmentally Disbled Induction agent- Reactive airway disease, trauma patients (hypovalemia), cardiac disease Adjuvant- to decrease opioid use

Question 37

Name three Acetyl cholinesterase inhibitors used to reverse neuromuscular blockade?

Answer 37

Neostigmine, Edrophonium, Pyridostigmine

Question 38

Of Neostigmine, Edrophonium, Pyridostigmine what has the longest duration of action?

Answer 38

Pyridostigmine

Question 39

MOA of dexmedetomidine?

Answer 39

Binds a2a and a2b in LC and SC--> sedation, sympatholysis, analgesia

Question 40

Use of dexmedetomidine?

Answer 40

awake intubations, craniatomies, adjunct to general anesthesia (in pts susceptible to narcotic induced resp depression)

Question 41

Name three amino steroid non-depolarizing NMB.

Answer 41

Pancuronium, Vecuronium, Rocuronium

Question 42

MOA of Pancuronium, Vecuronium, Rocuronium?

Answer 42

competitive blockade of Ach (no depolarization)

Question 43

What Amino steroid non-depolarizing blocker causes increased HR?

Answer 43

Pancuronium

Question 44

Length of action of Pancuronium, Vecuronium, Rocuronium?

Answer 44

P- long V-intermediate R- intermediate

Question 45

What are Pancuronium, Vecuronium, Rocuronium used for?

Answer 45

Skeletal muscle relaxation

Question 46

Name a depolarizing NMB?

Answer 46

Succinlycholine

Question 47

MOA of succinylcholine?

Answer 47

attaches to Ach receptors and overstimulates | first seen as disorganized contractions then paralysis

Question 48

What is unique about succinylcholine related to its duration of action?

Answer 48

Rapid onset, ultra-short Duration of action | CAN NOT be reversed

Question 49

SE of succinylcholine?

Answer 49

malignant hyperthermia, cardiac dysrhythmias, hyperkalemia, increased ICP and intraocular pressure myalgias, masseter spasm

Question 50

Use of succinylcholine

Answer 50

skeletal muscle relaxation (intubation)

Question 51

MOA of sugammadex?

Answer 51

complexes w/ rocuronium, rendering it inactive

Question 52

SE of sugammadex?

Answer 52

decrease in BP, N/V, dry mouth

Question 53

Name two isoquinoline NMBs.

Answer 53

Atracurium and Cisatracurium

Question 54

MOA of Atracurium and Cisatracurium?

Answer 54

competitive blockade of Ach (no depolarization)

Question 55

Use of isoquinoline NMBs?

Answer 55

skeletal muscle relaxant (pts w/ liver or renal dysfunction)

Question 56

SE of Atracurium?

Answer 56

histamine release w/ resultant hypotension and tachycardia