Pharmacology pt 2 Flashcards

1
Q

Metabolic ALKALOSIS is common following the administration of which diuretics?

A

Loop and thiazide

- loss of extracellular volume with constant extracellular HCO3

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2
Q

What receptors do loop diuretics act on in the ascending LOH?

A

Na-K-Cl transporter

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3
Q

What receptors do thiazide diuretics act on in the distal convoluted tubules?

A

Na-Cl reabsorption

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4
Q

Metabolic ACIDOSIS is common following the administration of which diuretics?

A

acetazolamide (carbonic anhydrase inhibitor)

  • inhibits the rxn btwn H2O, CO2, Carbonic acid, and bicarb -> bicarb builds up in urine
  • d/t bicarbonate excretion

Potassium sparing diuretics (spironolactone, amiloride)

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5
Q

You should not use acetazolamide in Pts with what lung condition ?

A

COPD

- can also impair CO2 elimination (not just increase HCO3 excretion)

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6
Q

What two metabolic disturbances are associated with diuretics?

A

Metabolic ALKALOSIS

  • loops
  • thiazide

Metabolic ACIDOSIS

  • acetazolamide
  • spironalactone
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7
Q

What diuretics act at:

  • distal convoluted tubule?
  • collecting ducts
A

distal convoluted tubule
- thiazide

collecting ducts
- spironalactone

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8
Q

Which pain medication is associated with QT prolongation?

A

Methadone

- concurrent use with other meds that also inhibit CYP3A4 -> cardiac arrhythmia

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9
Q

Half-life of methadone

A

20-60 hours

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10
Q

Metabolism of most drugs occurs via 2 processes - Phase I and Phase II reactions
- What is Phase I?

A

oxidative and reductive reactions

  • hydrolytic reactions
  • catalyzed by cytochrome P450
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11
Q

Metabolism of most drugs occurs via 2 processes - Phase I and Phase II reactions
- What is Phase II?

A

Conjugation of drug or its metabolites w. substrates (ie. glucuronic acid)
- once metabolized -> eliminated from body

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12
Q

What reaction occurs after large and prolonged thiopental dosing?

A

desulfurization reaction

–> produces pentobarbital -> CNS depressant activity

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13
Q

Remifentanil is metabolized by:

A

ester hydrolysis in the blood by plasma esterases

- safe in pts with ESRD

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14
Q

Buprenorphine MOA

A

u-opioid partial agonist

k-antagonist

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15
Q

Buprenorphine potency vs morphine

- effects at high dose

A

24-40x potency of morphine, half life of 3 hours

High dose - partial agonist ceiling effect
- (less respiratory depression)

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16
Q

Spironolactone MOA

A

competitive aldosterone antagonist

  • K sparing diuretic
  • retention K
  • excretion Na
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17
Q

_____ is the major counterregulatory hormone to insulin

A

Glucagon

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18
Q

Glucagon effects on the heart

A

Inotropic and chronotropic response

- activates G protein coupled receptors -> adenylyl cyclase -> increase cAMP

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19
Q

Glucagon is contraindicated in which 2 disease states?

A

Pheochromocytoma
- risk for hyperglycemia and severe HTN

Insulinoma
- risk of severe hypoglycemia

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20
Q

Glucagon resembles which vasopressors?

A

Epi
Norepi

*Inotropic and chronotropic response

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21
Q

Isoproterenol MOA

A

Nonselective Beta agonist
-> - activates G protein coupled receptors -> adenylyl cyclase -> increase cAMP

*Very similar to glucagon

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22
Q

How does ASA irreversibly inhibit platelet function?

A

Blocking formation of thromboxane A2

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23
Q

How many days does it take for your entire platelet pool to be replenished?

A

7 days

- 10% per day

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24
Q

What is the MOA of:
Clopidogrel (Plavix)
Ticagrelor (Brilinta)
Prasugrel (Effient)

A

Inhibit ADP receptor activation

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25
Q

What is the MOA of:
Eptifibatide (Integrilin)
Abciximab (Reopro)
Tirofiban (Aggrastat)

A

Blocks GP IIb/IIIa receptors

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26
Q

Example of antiplatelet agents

- Irreversibly inhibit plt function, so even if med no longer present, effect on plt still persists

A
  1. ASA
  2. Clopidogrel
  3. Ticagrelor
  4. Dipyridamole
  5. Abciximab
  6. Eptifibatide (integrillin)

*limited list

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27
Q

Examples of anticoagulation agents

- works via diff mechanisms, but can continue/hold perioperatively

A
  1. Warfarin
  2. heparin
  3. Fondaparinux
  4. Dabigatran (pradaxa)
  5. Rivaroxaban (xarelto)
  6. Apixaban (Eliquis)
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28
Q

MOA of:
Dabigatran (pradaxa)
Rivaroxaban (xarelto)
Apixaban (Eliquis)

A

Dabigatran (pradaxa)
- direct thrombin inhibitor

Rivaroxaban (xarelto)
Apixaban (Eliquis)
- direct factor Xa inhibition

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29
Q
NMBs are (hydrophilic/hydrophobic) w/t quaternary amine structure
- importance?
A

Hydrophilic
- (cirrhosis, CHF, RF): an increase in body water -> increase volume of distribution -> DECREASES plasma [ ] of NMBs, so you need to INCREASE the intubating dose

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30
Q

Which NMBs will have INCREASED duration of action with impaired hepatic metabolism?

A
  1. Roc
  2. Vecuronium
  3. Pancuronium
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31
Q

Sodium nitroprusside toxicity is a direct side effect of ____ and ____ toxicity.

  • Triad of:
    1. Elevated mixed venous oxygen (PVO2)
    2. Tachyphylaxis
    3. metabolic acidosis
A

cyanide

thiocyanate

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32
Q

Sodium nitroprusside toxicity is a direct side effect of cyanide and
thiocyanate toxicity.
- What Triad is seen?

A
  1. Elevated mixed venous oxygen (PVO2)
  2. Tachyphylaxis
  3. metabolic acidosis
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33
Q

Antidote for cyanide poisoning

A

Amyl nitrate

- converts Hgb to Methgb (which binds cyanide)

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34
Q

In pts with biliary disease, how does morphine affect the common bile duct?

A

Induce Biliary colic

- Opioids inhibit efferent innervation (smooth m) to bile duct -> frequent muscle contraction

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35
Q

Max dose of neostigmine (acetylcholinesterase inhibitor)

A
  1. 07 mg/kg

- too much can INCREASE risk of developing weakness

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36
Q

Which anesthetic gas produces that largest [ ] of fluoride ions upon metabolism?

A

Methoxyflurane and Sevoflurane
- fluoride induced nephrotoxicity to the collecting ducts, inhibiting ADH

*Halothane causes HEPATOtoxicity

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37
Q

How does halothane decrease BP?

A

Mainly by reducing cardiac output

*the other inhaled anesthetics lower BP by decreasing SVR

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38
Q

How does nitrous oxide decrease BP?

A

It generally doesnt

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39
Q

Can nitrous oxide be used in laparoscopic or bariatric surgery?

A

Yes

  • duration is more important than the type of surgery (>4 hours)
  • but avoid if bowel is already distended or ischemic
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40
Q

How fast can nitrous oxide expand a pneumothorax?

A

double in 10 min

triple in 15 min

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41
Q

Which anesthetic drug below will cause the least dmg with local tissue extravasation (vesicant)?

propofol, diazepam, phenytoin, promethazine, thiopental

A

propofol

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42
Q

Can pts with PCN allergy with no h.o severe reaction (whether IgE or non IgE mediated) receive cephalosporin abx?

A

Yes

*rash does NOT count as a severe rxn

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43
Q

Difference btwn LMWH and UFH?

A

UFH: inactivate factor Xa and IIa

LMWH: inactivate factor Xa only

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44
Q

PTT is used to assess _____ pathway.

Used to monitor ____.

A

Intrinsic (VIII, IX, XI, XII)
and common pathway (II, V, X, fibrinogen)

Unfractionated heparin

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45
Q

PT is used to assess _____ pathway.

Used to monitor ____.

A
Extrinsic pathway ( Tissue factor and VII)
and common pathway (II, V, X, fibrinogen)

Warfarin

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46
Q

Anti-Xa assay is Used to monitor ____.

A

LMWH

*PTT is used to monitor UF

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47
Q

Norepinephrine is a naturally occurring catecholamine secreted at the _________ synapses and is release from the _______

A

postganglionic sympathetic

adrenal gland

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48
Q

The ____ reflex mediates a decrease in HR secondary to increase blood pressure from an increase in SVR

A

baroreceptor

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49
Q

Beta 1 activity

A

increase HR, contractility, and cardiac output

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50
Q

Norepi has alpha 1 and beta 1 activity, which one predominates?

A

alpha > beta

  • leads to more arterio/venoconstriction than increasing HR
  • worsen renal and splanchnic blood flow
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51
Q

Dosing for NDMB prior to succinylcholine (1 mg/kg) to prevent fasciculations?

A

10% of ED95 dose
ie: roc 0.03 mg/kg
vecis 0.05 mg/kg
cis is 0.05 mg/kg

*ED is effective dose, NOT intubating dose

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52
Q

What does ED50 mean?

A

Median effective dose that will produce an effect in 50% of the population that it is administered to

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53
Q

What does ED95 mean?

A

Median effective dose that will produce an effect in 95% of the population that it is administered to

  • different meaning with NMBDs
  • 95% twitch suppression in 50% of the population
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54
Q

What happens when you mix propofol with lidocaine?

A

It decreases the stability of propofol w/in 30 min, inc risk of PE
- give immediately after mixing

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55
Q

Most effective way to reduce pain associated w/ injection of propofol

A
  1. injection in antecub vein

2. modified bier block

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56
Q

Anesthetic drugs associated with myoclonus

A
Etomidate
Ketamine
Methohexital
Suxx
Propofol

*pretreatment with midazolam helps

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57
Q

Transdermal fentanyl patch max plasma [ ] ? How long does it take to decrease [ ] by 50%?

A

30 hours

24hours

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58
Q

Following neostigmine administration, how does this affect succinylcholine?

A

Phase I augmentation

  • prolonged DOA (~30 min)
  • common after laryngospasm
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59
Q

Milrinone MOA.

WHere is it excreted?

A

PDE III inhibitor
- acts on cAMP -> inodilator

Kidneys /urine
- Lower dose if RF

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60
Q

Milrinone effect on:
cardiac index
systemic vascular resistance
pulmonary vascular resistance

A

Increase CI (without increasing myocardial oxygen demand)

Decrease both systemic and pulmonary vascular resistance

61
Q

What doses of amiodarone are associated with bradycardia?

A

HIGH doses

62
Q

Amiodarone MOA

- half life?

A

block potassium, calcium, and sodium channels
- lesser extent: alpha, beta

45 days
- risk of toxicity extends that long after d/c

63
Q

What % of pts on amiodarone develop hypothyroidism?

A

20%

64
Q

Clonidine MOA

A

alpha 2 agonist

  • analgesic
  • potentiates opioids (morphine)
65
Q

Which drug lasts longer in an epidural, clonidine or morphine?
Which one causes more hypotension?

A

Clonidine

Clonidine

66
Q

H2 blockers (Cimetidine, ranitidine, famotidine) oral vs IV onset time? WHich one reduces gastric volumes?

A

1 hour - PO
30 min - IV (ranitidine IV will be 1 hour)

Cimetidine, famotidine

*Ranitidine does NOT reduce gastric volumes

67
Q

PPI MOA and onset time?

A

binds H+-K+ pumps

2-4 hours

68
Q

Most common side effect of water soluble fospropofol (gets metabolized to propofol)

A
  1. parasthesias
    - > 50% of pts
  2. pruritus
    - localized to genitals

(in propofol its 10%)

69
Q

DOes phenylephrine affect splanchnic perfusion?

A

yes

- arterial and venous constriction

70
Q

Aminoesters (procaine, chloroprocaine) are derivatives of ______

A
paraaminobenzoic acid (PABA_
- known allergen, hapten
71
Q

If pts have an “allergic” rx to Aminoamides (lidocaine, bupivacaine, ropivacaine), what is it likely d/t?

A

preservatives

- methylparaben

72
Q

If local anesthetics are stored with epi, and they have an “allergic” rxn, what could it be d/t?

A

metabisulfite

73
Q

Volatile anesthetic effects on CBF and CMRO2

A

Increase CBF
Decrease CMRO2
- phenomenon known as “uncoupling”, as they usually parallel

*CMRO2 usually decreases with hypothermia and sleep

74
Q

All volatile anesthetics (increase/decrease) CMRO2

A

decrease

*except nitrous oxide, it does NOT cause decoupling of CBF and CMRO2

75
Q

Nitrous oxide effects on CBF and CMRO2

A

Increase both

All other volatile anesthetics Increase CBF
Decrease CMRO2

76
Q

All IV agents except _____ decrease CMRO2 and decrease CBF

A

ketamine
- inc CBF and decrease CMRO2

*fentanyl has no effect

77
Q

Which immunosuppressant PROLONGS NDMBs?

A

cyclosporine

  • neurotoxic
  • nephrotoxic
78
Q

How does St. John’s wort affect drugs

A

CYP3A4 inducer

- metabolizes drugs -> subtherapeutic drug levels

79
Q

Hydromorphone dosing should be (increased/decreased) in pts with ESRD

A

decreased

  • accumulates in kidneys
  • Hydromorphone-3-glucuronide is toxic metabolite
80
Q

Meperidine, a synthetic opioid for post op shivering, dosing should be (increased/decreased) in pts with ESRD

A

decreased

  • accumulates in kidneys
  • Normeperidine is toxic metabolite
81
Q

Morphine dosing should be (increased/decreased) in pts with ESRD

A

decreased

  • accumulates in kidneys
  • Morphine-6-glucuronide is active metabolite -> prolong sedation and respiratory depression
82
Q

Why do you need to be careful using meperidine, a synthetic opioid for post op shivering, in pts using MAOIs (ie. selegiline)?

A

Opioid that also has weak SNRI

–> serotonin syndrome

83
Q

All opioids except remifentanyl is metabolized in the _____

A

liver

  • biotransformation in liver by phase I –>
  • phase II conjucation
84
Q

Cytochrome ______ is responsible for metabolism of most anesthetics, lidocaine, and dexamethasone

A

P450 3A4

CYP3A4

85
Q

Cytochrome ______ is responsible for metabolism of PPI (omeprazole) and antidipressants

A

P450 2C19

CYP2C19

86
Q

Cytochrome ______ is responsible for metabolism of phenytoin, warfarin, ibuprofen

A

P450 2C9

CYP2C9

87
Q

*Cytochrome ______ is responsible for metabolism of codeine, BBs, antiarrhythmics, diltiazem, tramadol

A

P450 2D6

CYP2D6

88
Q

P450 3A4
(CYP3A4)
is responsible for metabolism of _______

A

most anesthetics, lidocaine, and dexamethasone

89
Q

P450 2C19
CYP2C19
is responsible for metabolism of _______

A

PPI (omeprazole) and antidipressants

90
Q

P450 2C9
(CYP2C9)
is responsible for metabolism of _______

A

phenytoin, warfarin, ibuprofen

91
Q

P450 2D6
(CYP2D6)
is responsible for metabolism of _______

A

codeine, BBs, antiarrhythmics, diltiazem, tramadol

92
Q

Where is the Na/K/Cl transporter located for antihypertensives?

A

In the LOH

*Na/Cl transporter is in the distal conv tubule

93
Q

Most common GABA B receptor agonist

A

baclofen for “B”
- B receptors are linked to K+ channels

*A is Cl-

94
Q

Most anesthesia drugs are GABA (A / B) activators?

A

A for “anesthetics”

- allows Cl’ to enter neuron and hyperpolarize cell

95
Q

How does NMDA receptor activation work?

A

Inc intracellular calcium -> second messenger
- both voltage gated AND ligand gated

2 conditions must be met for NMDA receptor to become activated

  1. GLutamate or glycine must be bound (ligand gated)
  2. Cell must be depolarized (voltage gated)
96
Q

Insulin and glucagon use which receptors as a second messenger system?

A

cAMP

97
Q

Nitroglycerin, sodium nitroprusside, nitric oxide, sildenafil use which receptors as a second messenger system?

A

cGMP

98
Q

Tirofiban, abciximab, eptifibatide MOA

A

Glycoprotein (GP) IIb-IIIa receptor inhibitor

- prevent platelet aggregation and thrombus formation

99
Q

Clopidogrel, prasugrel, ticagrelor, and ticlopidine MOA

A

ADP receptor inhibitors

- impair ADP dependent activation of GP IIb-IIIa complex

100
Q

What type of shunt is formed with a foreign body in the R mainstem bronchus?

A

R -> L INTRApulmonary shunt
Prevent ventilation to a lung that is perfused, creating a SLOWER induction
- rate of rise for arterial concentration of gas will DECREASE (more obvious with LESS soluble agents, desflurane and nitrous oxide)

101
Q

How do R -> L intracardiact shunts (ie. eisenmenger syndrome) affect IV induction?

A

Faster induction
- lungs are bypassed

*L to R shunts and intrapulmonary shunts will have minimum effect

102
Q

Intrapulmonary or Intracardiac (R to L) shunt will affect inhalational and IV inductions how?

A

R to L Intrapulmonary

  • Decreases inhalational induction
  • No effect on IV induction

R to L intracardiac

  • Decreases inhalational induction
  • Increases IV induction
103
Q

Intracardiac (L to R) shunt will affect inhalational and IV inductions how?

A

No effect on inhalational agents

No effect on IV agents

104
Q

In the presence of an intrapulmonary shunt, the speed of induction will affect which gas (most to least)?

A

Nitrous Oxide > Desflurane > Sevoflurane > Isoflurane

*
Shunts typically affect insoluble agents more than soluble agents

105
Q

Drug of choice in electroconvulsive therapy (ECT)

A

Methohexital (short acting barbiturate)

  • Lowers sz threshold
  • cause hiccups
106
Q

BDZ effects on respiratory system

A

Decrease TV, which dec MV

107
Q

Which commonly used BDZ (midazepam, lorazepam, diazepam) has the fastest onset of action and shortest DOA

A

Midazolam

108
Q

How is the CO2 sensitivity affected with BDZ?

A

Sensitivity to CO2 is decreased

109
Q

Chronic barbiturate admin (increases / decreases) the DOA of drugs metabolized by the CYP450 enzyme

A

DECREASES

- so you would need to increase the dose requirement

110
Q

Commonly used anesthesia drugs metabolized by CYP450 34A

A
  1. Acetaminophen
  2. Statins
  3. Alprazolam, Diazepam, Midazolam
  4. Bupivacaine, Lidocaine, Ropivacaine
  5. Codeine, Fentanyl, Alfentanil, Sufentanil
  6. Warfarin
  7. Varapamil, Diltiazem, Nicardipine, Nifedipine
  8. Omeprazole

*Chronic use of barbiturates decreases DOA of these drugs, and you will need to INCREASE dose requirements

111
Q

How does morphine and fentanyl affect the thoracic and abdominal wall?

A

In large doses over a short period of time = wall rigidity

112
Q

Which CYP do SSRIs (fluoxetine and paroxetine) significantly inhibit?

A

CYP2D6

  • converts codeine, hydrocodone, oxycodone to metabolites w/ greater potency (morphine, hydromorphone, oxymorphone)
  • You have increased opioid requirements now bc active forms are reduced
113
Q

When reversing NDNMB, which cholinesterase inhibitor should be paired with which anticholinergic?

A

Edrophonium - Atropine (onset 1 min)
Neostigmine / Pyridostigmine - Glyco (2-3 min)

*similar onset and DOA

114
Q

Which is the only cholinesterase inhibitor that crosses the BBB?

A

Physostigmine

- great against anticholinergic overdose or organophosphate poisoning

115
Q

The rate of rise in FA/FI ratio is a marker of ____

A

volatile anesthetic uptake by the blood

116
Q

The greater the solubility of an inhaled anesthetic, the more ____ the uptake into the bloodstream

The _____ the uptake, the slower the rate of rise of FA/FI

Uptake into the bloodstream is the primary determinant of _____

The gases with the ______ solubilities in the blood (desflurane) will have the fastest rise in FA/FI

A

Rapid

Greater

FA (alveolar anesthetic concentration)

Lowest

117
Q

If ventilation is fixed, an increase in cardiac output from 2 to 20L/min will (increase / decrease) alveolar anesthetic concentration (FA) .

A

DECREASE
- by augmenting uptake

This will slow the rise of FA/FI ratio.
More prominent w/ soluble anesthetics.

118
Q

Factors that tend to INCREASE the rate of rise of FA/FI

A
  1. Low blood:gas partition coefficient (solubility)
  2. Low cardiac output
  3. High min ventilation
  4. Low (Parterial - Pvenous), meaning less blood uptake
119
Q

Epidural 2-Chlorprocaine onset time? DOA?

A

6-12 min d/t high [ ] of LA

45-60 min plain
60-90 w/ epi

120
Q

Butorphanol MOA

A

Synthetic mu agonist-antagonist
Partial agonist at K-opioid receptor
- relieves biliary colic

121
Q

Which receptors do dopamine stimulate and at what doses?

A

D 1: low concentration
- vasodilation of renal, mesenteric, coronary vasculature -> inc GFR and blood flow

Beta 1 - high dose
- inc HR, SBP, pulse pressure

Alpha 1 - highest doses
- peripheral vasoconstriction

122
Q

Side effects of dopamine

A
Tachyarrhythmias
Dec splanchnic blood flow -> gut ischemia
Dec TSH, prolactin, GH
Dec Ventilatory response
WOrsen V/Q mismatch in lungs
123
Q

Opioid w/ fastest Onset of action

A

Alfentanil

- high unionized fraction d/t low pKa 6.5 (90% of drug in unionized form)

124
Q

For opioids, ______ correlates with DOA the majority of the time

A

lipid solubility

  • Hydromorphone lipid solubility of 2
  • Morphine lipid solubility 1.4

*Fentanyl is 816
sufentanil is 1700

125
Q

Eating tons of Natural licorice can lead to what abnormality?

A

It blocks 11-beta-hydroxysteroid -> hyperaldosterone effects -> all the sx of Conn syndrome

  1. HYPOkalemia
    - activates Na-K-ATPase channels in renal proximal tubules
    - Na reabsorption and K secretion
  2. HTN
  3. HYPERnatremia
  4. FLuid overload
  5. Metabolic alkalosis
126
Q

What describes a drug with a large volume of distribution?

*Vd = Drug dose / Plasma [ ]

A

Lipophilic
High amt of TISSUE protein binding
- Inversely proportional to unbound drug in the tissue
Low amt of plasma protein binding
- Directly proportional to unbound drug in the plasma

127
Q

Lipophilic
High amt of TISSUE protein binding
- Inversely proportional to unbound drug in the tissue
Low amt of plasma protein binding
- Directly proportional to unbound drug in the plasma

*Does this describe a drug with large or small volume of distribution (Vd)?

A

LARGE Vd

*high affinity for tissue components (tissue proteins, tissue lipids)

128
Q

Hydrophilic
High degree of PLASMA protein binding
Low degree of TISSUE protein binding

*Does this describe a drug with large or small volume of distribution (Vd)?

A

Small Vd

129
Q

What do time constants refer to?

A

The volume or capacity of the circuit (Vc) / FGF

Time it takes to reach equilibrium

130
Q

How do volatile anesthetics prolong NMBs?

A

Decrease the sensitivity of the postjunctional skeletal muscle

131
Q

Two drugs associated with genital burning and itching

A

Fospropofol (prodrug of propofol)

Awake dexamethasone

132
Q

3 major mechanisms for nitroprusside toxicity

A
  1. Cyanide ions bind cytochrome C oxidase and inhibits cellular aerobic respiration
  2. Formation of cyanmethemoglobin (unable to carry oxygen)
  3. Thiocyanate production (CNS events)
133
Q

How does glucagon increase cardiac contractility?

A

Increases intracellular cAMP - > inc myocardial contractility (inotropic and chronotropic)

134
Q

Glucagon physiologic effects

A
  1. Inhibit gastric motility
  2. Promote hepatic gluconeogenesis
  3. Relax sphincter of Oddi
  4. Inotrope and chronotrope
135
Q

Which p450 enzyme is induced by St. Johns wort?

A

CYP450 3A4

  • metabolizes drugs -> subtherapeutic drug levels
  • Affects codeine, BBs, antiarrhythmics, diltiazem, tramadol, SSRI, MAOI
136
Q

Metoclopramide MOA and its effects on:

  • Gastric volume
  • pH
A

Dopamine antagonist

    • Inc lower esophageal sphincter tone -> enhance gastric emptying -> decrease gastric vol
  • no change pH
137
Q

Sodium citrate MOA and its effects on:

  • Gastric volume
  • pH
A

Weak base reacts w/ HCl

  • no change vol
  • increase gastric pH
138
Q

How does Cytochrome p450 work?

A

heme protein that utilizes oxygen to OXIDIZE organic compounds
- part of Phase I metabolism

139
Q

Phase I drug metabolism involves ____

Phase II involves ____

A

I: oxidation, reduction, hydrolysis
- inactivate drug

II: conjugation
- (either glucuronic acid or sulfate is added to drug to make it easily excreted from kidney/liver)

140
Q

Chronic barbiturate use ______ cytochrome P450 activity.

A

Increases

- therefore, metabolism of drugs by P450 is increased. ie. BDZ

141
Q

The blood:gas coefficient refers to the _________.

The oil:gas coefficient refers to the ____________.

A

The rate of rise of the FA/Fi and is related to the SOLUBILITY and the speed of inhalational induction

LIPOPHILICITY and is related to the anesthetic potency and MAC

142
Q
Max allowable dose for:
Lidocaine (plain):
Lidocaine (w/ epi):
Bupivacaine (plain):
Bupivacaine (w/ epi):
Ropivacaine (plain only): 
Chloroprocaine (plain only):
A
Lidocaine (plain): 5mg/kg
Lidocaine (w/ epi): 7mg/kg
Bupivacaine (plain): 2.5 mg/kg
Bupivacaine (w/ epi): 3 mg/kg
Ropivacaine (plain only): 3 mg/kg
Chloroprocaine (plain only): 12 mg/kg
143
Q

What does cAMP do in the heart vs in the peripheral smooth muscles?

A

Inc intracellular cAMP

Heart:
cAMP -> increased influx of intracellular calcium stores ->
enhance cardiac inotropy

Peripheral smooth muscles:
cAMP -> smooth muscle VASODILATION and decreased peripheral vascular resistance

*Milrinone is a PDE III INHIBITOR, which impairs cAMP breakdown

144
Q

*Milrinone is a PDE III INHIBITOR, which impairs _____ breakdown

A

cAMP

- Inodilator

145
Q

Adrenaline (epinephrine), isoprenaline (isoproterenol), and dopamine undergo (extensive / no) metabolism in the lungs

A

NO metabolism in lung

146
Q

Effects of burns on:

  • Pseudocholinesterase lvls
  • ACh receptor numbers
  • Protein binding
A
  • Pseudocholinesterase lvls: decreased
  • ACh receptor numbers: increased
  • Protein binding: increased (meaning less free drug is available)

*Doses of most NDNMBs must be increased 2-5x in burn pts

147
Q

Mivacurium metabolized by:

A

Pseudocholinesterase alone

*atracurium has some metabolism by pseudocholinesterase

148
Q

*Doses of most NDNMBs must be increased ___x in burn pts

A

2-5x

*mivacurium needs the least increase (1-2x) b/c burn pts have decreased lvls of pseudocholinesterase and are more sensitive to it

149
Q

What are the safest opioids to use in ESRD?

A

fentanyl and methadone
*no concern for metabolites accumulating

*but dose reduction still recommended