Everything

Question 1

What is the mechanism for toxic sideffects of Nitrous Oxide?

Answer 1

Blocks Vitamin B12 dependent enzymes, such as thymidylate synthase (DNA synthesis) and methionine synthase (myelin formation).

Question 2

What are the side effects of nitrous oxide?

Answer 2

Bone marrow suppression, peripheral neuropathies.

Question 3

What type of patients should you not give nitrous oxide to?

Answer 3

Pregnant patients (possible teratogenic).

Question 4

What conditions are hazardous to use nitrous oxide in?

Answer 4

Venous or arterial air embolism, pneumothorax, acute intestinal obstruction, intracranial air, pulmonary air cysts, intraocular air bubbles, and tympanic membrane grafting.

Question 5

What effect does Isoflurane have on coronary arteries? Why could this be a problem?

Answer 5

It dilates coronary arteries, potentially creating a steal situation, where blood is diverted away from fixed stenotic lesions.

Question 6

What effect does isoflurane have on the bronchi?

Answer 6

It is bronchodilatory.

Question 7

How much faster is desflurane than isoflurane?

Answer 7

About 50% faster wake up time.

Question 8

What is the blood gas partition coefficient of nitrous?

Answer 8

0.47

Question 9

What is the blood gas partition coefficient of desflurane?

Answer 9

0.42

Question 10

What can rapid increases in desflurane concentration lead to?

Answer 10

Elevated HR, BP, and catecholamine levels.

Question 11

What can Desflurane, more than other volatiles, be degraded by dessicated CO2 absorbent into?

Answer 11

Carbon monoxide.

Question 12

What are contraindications for volatile anesthetics?

Answer 12

Severe hypovolemia, malignant hyperthermia, and intracranial hypertension.

Question 13

What is the solubility coefficient of sevoflurane?

Answer 13

0.65

Question 14

Why is cardiac output not maintained as well with sevoflurane, as it might be with isoflurane or desflurane?

Answer 14

Because sevoflurane does not increase heart rate, so CO is not maintained.

Question 15

What cardiac side-effect can sevoflurane have?

Answer 15

QT prolongation.

Question 16

What increases the amount of Compound A produced by sevoflurane administration?

Answer 16

Increased temperature of gas, low flow anesthesia, high sevoflurane concentration, and anesthetics of long duration.

Question 17

What enzyme metabolizes sevoflurane, and what multiplier is sevoflurane metabolized compared to isoflurane?

Answer 17

CPY-2E1, 10-25X more metabolized than isoflurane.

Question 18

What is the possible complication of sevoflurane metabolism?

Answer 18

Possible rise in inorganic fluoride, which can cause renal injury.

Question 19

What three factors affect inhaled anesthetic uptake?

Answer 19

Solubility, alveolar blood flow, and the difference between alveolar gas and venous blood gas partial pressure.

Question 20

What factors affect speed of recovery and induction?

Answer 20

Elimination of rebreathing, high fresh gas flow, low anesthetic-circuit volume, low absorption by the anesthetic circuit, decreased solubility, high cerebral blood flow, and increased ventilation.

Question 21

What are risk factors for halothane toxicity?

Answer 21

Multiple halothane anesthetics, middle aged obese women, persons with familial predisposition.

Question 22

What effect does repetitive administration of barbituates have?

Answer 22

Saturates peripheral compartments, minimizing redistribution and making half-life dependent on elimination only.

Question 23

What is the mechanism of action of barbituates?

Answer 23

Binding the GABAa receptor, increasing the duration of openings of a chloride-specific ion channel.

Question 24

What determines the duration of effect of “sleep” doses of barbiturates?

Answer 24

Time to redistribution, for example, Thiopental will redistribute within 20 minutes.

Question 25

What patient factors might barbiturates be a bad idea in?

Answer 25

Hypovolemia, B-blockade, and CHF, because you can get an uncompensated peripheral pooling of blood and direct myocardial depression, causing severe hypotension.

Question 26

What effect do barbiturates have on the brain?

Answer 26

They constrict cerebral vasculature, causing a decrease in cerebral blood flow, cerebral blood volume, and decrease intracranial pressure.

Question 27

What effect do barbiturates have on CPP?

Answer 27

Intracranial pressure decreases to a greater degree than arterial BP usually, so CPP increases.

Question 28

What side-effect can barbiturates have on the liver?

Answer 28

They can promote aminolevulinic acid synthetase, which stimulates formation of porphyrin (heme intermediary). This can precipitate acute intermittent porphyria.

Question 29

What is the mechanism of benzodiazepenes?

Answer 29

Benzos bind to GABAa and increase the frequency of chloride ion opening.

Question 30

What is the treatment for benzodiazepene overdose?

Answer 30

Flumazenil

Question 31

What is the mechanism of Flumazenil?

Answer 31

Benzodiazepene receptor antagonist.

Question 32

Why do most benzodiazepenes have long half-lives? Why is midazolam different?

Answer 32

Long half-lives because of large volume of distribution. Midazolam has an increased hepatic extraction ratio, however, so it is shorter.

Question 33

How are benzodiazepenes excreted?

Answer 33

Urine.

Question 34

Can small doses of benzodiazepenes cause respiratory arrest?

Answer 34

Yes, although apnea is relatively uncommon, even small doses can cause respiratory arrest.

Question 35

What synergistic side-effect can you see with benzodiazepenes and opioids in induction?

Answer 35

Marked reduction in arterial BP and PVR.

Question 36

What effect does Ketamine have on SBP, HR, and ICP?

Answer 36

Increases all of them.

Question 37

What effect does Ketamine have on the bronchi?

Answer 37

It is a potent bronchodilator.

Question 38

What side effect happens with Etomidate?

Answer 38

Inhibition of enzymes involved in cortisol and aldosterone synthesis.

Question 39

What is special about the clearance of Propofol?

Answer 39

It exceeds hepatic blood flow, implying the existence of extrahepatic metabolism.

Question 40

What is propofol infusion syndrome?

Answer 40

Happens in children that are critically ill or young adult neurosurgical patients getting Propofol infusions, causing lipemia, metabolic acidosis, and death.

Question 41

What unique sideffects are beneficial in Propofol use?

Answer 41

Anti-pruritic and anti-emesis effects.

Question 42

What side-effects of Pancuronium should be considered?

Answer 42

Hypertension and tachycardia, caused by a combined vagal blockade and sympathetic stimulation.

Question 43

How is Cisatricurium degraded?

Answer 43

Hoffman elimination.

Question 44

What is the primary excretion of Vecuronium / Rocuronium?

Answer 44

Biliary

Question 45

What type of non-depolarizing muscle relaxants are Atra/Cisatracurium?

Answer 45

Benzylisoquinolones.

Question 46

What effect does long term administration of Vecuronium have, and why?

Answer 46

Extremely long neuromuscular blockade, likely from accumulation of active 3-hydroxy metabolite.

Question 47

What non-depolarizing muscle relaxant has an onset as fast as Succinylcholine? At what cost?

Answer 47

Rocuronium (0.9 mg/kg), lasts much longer.

Question 48

What non-depolarizing muscle relaxants are partially excreted by the kidneys, and thus last longer in renal failure patients?

Answer 48

Vecuronium, pancuronium, doxacurium, and pipecuronium.

Question 49

Why is succinylcholine relatively contraindicated in routine child management?

Answer 49

Risk of hyperkalemia, rhabdomyolysis, and cardiac arrest in children with unknown myopathies.

Question 50

What can happen with excessive doses of acetylcholinesterase inhibitors?

Answer 50

Paradoxical potentiation of NDMB.

Question 51

If you have a prolonged action of a NDMB from hepatic or renal insufficiency, what will likely happen to the duration of your acetylcholinesterase inhibitor?

Answer 51

Also increase, so everything will be ok.

Question 52

What is the suggested endpoint for NDMB reversal?

Answer 52

Sustained tetany for 5s in response to 100hz stimulus.

Question 53

How does Sugammadex work?

Answer 53

Bonding with steroidal NDMBs.

Question 54

CPY2D6 metabolizes which drugs?

Answer 54

Codeine, B-blockers, diltiazem, tramadol.

Question 55

CYP2C9 metabolizes which drugs?

Answer 55

Warfarin, phenytoin, ibuprofen

Question 56

CYP3A4 metabolizes which drugs?

Answer 56

Most anesthetics (incl. fentanyl), local anesthesia, and dexamethasone.

Question 57

What enzyme does Midazolam inhibit?

Answer 57

CYP3A4, which can prolong the effect of fentanyl.

Question 58

CYP3C19 metabolizes which drugs?

Answer 58

Antidepressants and PPIs

Question 59

MC1R metabolizes which drug?

Answer 59

Morphine

Question 60

Damage to the anterior hypothalamus can cause what problem?

Answer 60

Thermal dysreguation (temperature problems)

Question 61

Damage to the medial hypothalamus/posterior pituitary can cause which problems?

Answer 61

Hypotension and polyuria (cannot make vasopressin)

Question 62

What is the formula for mL of anesthetic in a bypass chamber?

Answer 62

(Vapor pressure of Gas x mL of Flow)/(Atm pressure - Gas vapor pressure)

Question 63

What is the formula for chest wall compliance?

Answer 63

1/Ccw = 1/Crs - 1/Clung

Question 64

What effect does spinal anesthesia have on the GI system?

Answer 64

Increased secretions, nausea, vomiting, etc from unopposed parasympathetic activity (spinal = sympathectomy)

Question 65

Mnemonic for rebreathing in mapleson circuit during spontaneous circulation?

Answer 65

A > D> C > B (All dogs can breathe)

Question 66

Mnemnic for rebreathing in mapleson circuit during controlled ventilation?

Answer 66

D > B > C > A (dead babies can't assist)

Question 67

How is Nicardipene metabolized?

Answer 67

Via the liver.

Question 68

What is the side effect of Amiloride?

Answer 68

Can cause hyperkalemia (it is a potassium sparing diuretic)

Question 69

What are the four potassium sparing diuretics?

Answer 69

Amiloride, Spironolactone, Triamterene, Eplneronone

Question 70

What can HCTZ increase in the serum?

Answer 70

Hypercalcemia, hyperuricemia, hyperglycemia

Question 71

Acoustic impedence is the product of which two characteristics?

Answer 71

Density and propogation of the speed of sound.

Question 72

Plasma volume is what % of extracellular volume?

Answer 72

25%