Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

OB Test 2 > Drug Categories, Placental Transfer > Flashcards

Drug Categories, Placental Transfer Flashcards

1
Q

Category A

A

No risk and find no evidence of harm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Category B

A

Animal studies show no risks but there are no controlled studies on pregnant women

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Category C

A

Animal studies have shown risk but no human studies

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Category D

A

Positive evidence of potential for fetal risk

-in life threatening situation might use

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Category X

A

Contraindicated in pregnancy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

How many commonly used drugs are known as teratogens?

A

20-30

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What percentage of medications in the physician desk reference are category X?

A

7%

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

When a new medication becomes available, what category is it automatically placed in (even w/o any studies)?

A

Category C

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q 
Common anesthetic drug categories:
Propofol 
Versed
Lidocaine
Fentanyl
Morphine
Succinylcholine
A 
Propofol : B
Versed: D
Lidocaine : B
Fentanyl : C
Morphine : C
Succinylcholine: C
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Only doses of Succinylcholine above what causes problems?

A

300mg

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q 
Induction agent drug categories:
Etomidate
Ketamine
Methohexital
Propofol
Thiopental
A 
Etomidate: C
Ketamine: B
Methohexital: B
Propofol: B
Thiopental: C
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q 
Inhaled anesthetic agent drug categories:
Desflurane 
Halothane
Isoflurane
Sevoflurane
A

Desflurane : B
Halothane : C
Isoflurane : C
Sevoflurane : B

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q 
Local anesthetic drug categories:
2-Chloroprocaine
Bupivacaine
Lidocaine
Ropivacaine
Tetracaine
A 
2-Chloroprocaine: C
Bupivacaine: C
Lidocaine: B
Ropivacaine: B
Tetracaine: B
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q 
Opioid drug categories:
Alfentanil
Fentanyl
Sufentanil
Meperidine
Morphine
A 
Alfentanil: C
Fentanyl: C
Sufentanil: C
Meperidine: C
Morphine: C
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Which opioid is the best choice in pregnancy? Why?

A

Sufentanil

  • highly lipid soluble
  • more rapid uptake by CNS, so less absorption in maternal and umbilical veins
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Doses of fentanyl below what are usually not an issue?

A

< 1mcg/kg

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What trimester is fentanyl usually avoided?

A

First

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Which opioids cross the placenta?

A

All of them

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Which opioids cross the placental barrier very easily?

A

Meperidine and Morphine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Which LA is metabolized so quickly in fetal blood that even with acidosis there is no substantial exposure or ion trapping?

A

2-Chloroprocaine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What is the downside to using 2-Chloroprocaine?

A

Doesn’t last long

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What purpose does the placenta serve?

A

Brings maternal and fetal circulations into close apposition, without substantial interchange of maternal and fetal blood
-for transfer of gases, nutrients, and wastes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Uterine arteries divide into?

A

Spiral arteries

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What spurts blood into the intervillous space?

A

Spiral arteries

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

What are the microscopic tissue layers that separate the fetal and maternal blood?

A

Fetal Trophoblast
Fetal Connective Tissue
Endothelium of fetal capillaries

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

Why are the tissues that separate the fetal and maternal blood so thin?

A

To allow easy transfer

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

What is the intervillous space?

A

Essentially a huge blood sinus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

What are the 2 sides of the intervillous space, and which side is which?

A

Chorionic plate: fetal side

Basal plate: maternal side

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

The intervillous space is divided into what?

A

Compartments called lobules

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

How much maternal blood can the intervillous space accommodate?

A

~350mL

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

How does maternal blood enter and drain from the intervillous space?

A

Enters via spiral arteries

Drains via decidual veins

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

The umbilical cord contains how many arteries and how many veins?

A

2 umbilical arteries and 1 umbilical vein

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

Umbilical arteries flow in what direction

A

Umbilical arteries carry deoxygenated nutrient-depleted blood from the fetus to the placenta

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

What is carried and in what direction in the umbilical vein?

A

Carries nutrient-rich and waste-poor blood to the fetus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

What hormones/substances does the placenta produce?

A 
Estrogen
Progesterone
Proteins
Enzymes
Polypeptide hormones
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

List the transport mechanisms that transport substances across the placenta:

A 
Passive transport
Facilitated transport
Active transport
Pinocytosis
Bulk flow
Breaks
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

What is passive transport?

A

Diffusion

  • no energy required
  • depends on concentration gradients
  • O2, CO2, Fatty acids, smaller ions (Na and Cl)
  • molecular weights less than 600 Da
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

What is facilitated transport?

A

Facilitated diffusion

  • carrier mediated transport
  • relatively lipid-insoluble molecules
  • still travel down concentration gradients
  • Glu, other carbs
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

What is active transport?

A

Requires cellular energy
Involves carrier molecules
Substances can move against concentration gradients
Amino acids, water-soluble vitamins, larger ions (Ca, Fe)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

What are the 2 types of active transport?

A

Primary and Secondary

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

What is primary active transport?

A

Movement occurs against concentration gradient
Uses special protein carrier
Uses energy derived from ATP

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

What is secondary active transport?

A

One substance moving down its concentration gradient acts as a carrier for a substance moving against its concentration gradient

  • sodium is usually the carrier
  • amino acids usually the molecule being carried
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q

What is pinocytosis?

A

Involves molecules being enclosed in small vesicles that travel through the cell membrane
Requires energy
Ex: immunoglobulins

44
Q

What is bulk flow?

A

Passage of substances resulting from a hydrostatic or osmotic gradient
Ex: water movement between mother and fetus

45
Q

What is breaks?

A

Breaks in the villi can allow fetal tissue to enter the intervillous space and transfuse into the mother’s circulation
-erythroblastosis fetalis

46
Q

What is erythroblastosis fetalis?

A

When the fetal Rh+ red cells enter the vascular system of the Rh- mother

47
Q

What medication prevents erythroblastosis fetalis reaction?

A

Rhogan

48
Q

Factors that affect rate of diffusion across the placenta

A

Concentration gradient
Area of the placenta
Permeability of placental membrane

49
Q

Factors that affect the concentration gradient

A

Concentration in maternal arterial blood
Concentration in fetal arterial blood
Maternal intervillous blood flow
Fetal-placental blood flow
Diffusing capacity of placenta
Ratio of maternal to fetal blood flow in exchanging areas
Binding of substances to molecules and dissociation rates

50
Q

Most of our anesthetic drugs are passed how?

A

Passive Diffusion

51
Q

What are the determinants of permeability?

A 
Molecular size
Lipid solubility
Electrical charge
-charged molecules do not cross easily
-Succs is charged
52
Q

Which side typically has more protein (for protein binding drugs)?

A

Maternal side

53
Q

What is the dividing line between substances that cross easily and substances that don’t?

A

1000 daltons

Ex: heparin is >6000 so it will not cross; Coumadin is 330 daltons

54
Q

What crosses the placenta more easily lipid soluble or lipid insoluble substances?

A

Lipid soluble cross more rapidly

55
Q

What is the Bohr effect?

A

Describes hemoglobins oxygen binding affinity is inversely related to both acidity and the concentration of CO2

56
Q

How is oxygen transport affected by the Bohr effect in pregnancy?

A

HGB dissociation curve shifts to the right with rise in H+

  • fetal to maternal transfer of CO2 makes mom more acidotic and fetus more alkalotic
  • this acidotic shift in mom liberates more O2 from mom
57
Q

What is the oxyhemoglobin dissociation curve shift in mother and fetus?

A

Mom: right shift
Fetus: left shift

58
Q

Factors that affect drug transfer across the placenta

A 
Lipid solubility 
Protein binding
pKa/pH
Blood flow
Molecular weight
Ionization
59
Q

If fetus becomes acidotic, what happens with drug transfer?

A

Drug transfer enhances and ion trapping can occur

60
Q

Most of the time, drugs pKa that are closer to physiologic pH have what affect on ionization and onset?

A

They will be less ionized and have a faster onset

61
Q

pKa of LA:
Procaine
2-Chloroprocaine
Tetracaine

A

Procaine: 8.9
2-Chloroprocaine: 8.7
Tetracaine: 8.5

62
Q 
pKa of LA:
Lidocaine
Bupivacaine
Ropivacaine
Mepivacaine
A

Lidocaine: 7.8
Bupivacaine: 8.1
Ropivacaine: 8.1
Mepivacaine: 7.6

63
Q

2-Chloropraine has a pKa of what? But why is it unique?

A

8.7

It’s onset is rapid due to the high dosage requirement

64
Q

What anticholinergics cross?

A

Atropine

Scopolamine

65
Q

What antihypertensives cross?

A

Beta blockers
Nitroprusside
NTG

66
Q

What benzodiazepines cross?

A

Diazepam

Midazolam

67
Q

What inducation agents cross?

A

Propofol
Thiopental
Ketamine

68
Q

What inhalation agents cross?

A

All

69
Q

What LAs cross?

A

All but 2-chloroprocaine

70
Q

What opioids cross?

A

All

71
Q

What anticoagulants cross?

A

Warfarin

72
Q

What vassopressors cross?

A

Ephedrine

73
Q

What anticholinergics do not cross?

A

Glycopyrrolate

74
Q

What anticoagulants don’t cross?

A

Heparin

75
Q

What NMB don’t cross?

A

All of them

76
Q

What anticholinesterase agents cross?

A

Neostigmine
Pyridostigmine
Edrophonium

77
Q

Which vassopressor causes a greater placental arterial pressure?

A

Ephedrine

78
Q

Due to the beta adrenergic effects of ephedrine (at higher doses) on the fetus what is seen in umbilical cord blood?

A 
Lower fetal pH
Lower base excess
High PCO2
Glucose
Lactate
Epinephrine
Norepinephrine
79
Q

Ephedrine in less than how many mg, is considered ok?

A

< 30mg

80
Q

Beta blockers are associated with?

A 
2x fetal growth restriction
Perinatal mortality
Neonatal bradycardia
Hypoglycemia
Respiratory depression
81
Q

What about using esmolol to blunt SNS with laryngoscopy?

A

It may cause significant and prolonged bradycardia leading to emergent c-section, this is not done!

82
Q

What 2 medications together produce the most depressant effects on mother and fetus?

A

Morphine and a benzo

83
Q

What doses of fentanyl appear safe for the term fetus?

A

Fentanyl <1 mcg/kg

84
Q

What affect does epidural opioids have on the mother and fetus?

A

Minimal effects on fetus

Rostral spread in mom causes drowsiness

85
Q

What is liposomal encapsulation and how does it affect placental transfer?

A

An anionic and neutral liposomes increase placental transfer
Cationic liposomes decrease placental transfer and placental tissue uptake
EX: liposomal encapsulation of valproic acid significantly decreases drug transfer and uptake (its a teratogen)

86
Q

How many drugs are known teratogenic drugs in animals, but only how many in people?

A

Animals: 1200
People: only 30

87
Q

List of teratogenic drugs

A 
Alcohol
Ace inhibitors (lisinopril, captopril, ramipril)
Cocaine
DES
Coumadin
Dilantin
Valproic acid
Retin A
Lithium
Thalidomide
Diazepam
88
Q

What about use of N2O during pregnancy?

A

N2O causes a 3x increase in fetal resorption
It rapidly inactivated methionine synthesis and leads to neurological and hematological symptoms from diminished DNA synthesis
Skeletal muscle defects
Situs inversus (reversal of organs)
Neuronal apoptosis in animals

89
Q

What has been found to occur with anesthetic gases and the fetus through pediatric brain growth?

A

Cause apoptotic neurodegeneration in the developing brain from the 4th month of gestation through pediatric brain growth and myelination of the neural sheath that peaks at age 12

90
Q

What factors worsen the neurodegeneration affects of anthesetic gases?

A

Longer the gas exposure

Multiple exposures

91
Q

What affects do kids suffer from this neurodegeneration?

A

Decreased IQ
Lack of impulse control
Less physical coordination
Prolonged behavioral deficits

92
Q

What anticholinergic should be used with neostigmine? Why?

A

Atropine

Neostigmine does cross the placenta and will cause fetal bradycardia, glyco will not cross but atropine will

93
Q

What can occur with large doses of atropine?

A

It can cause some fetal tachycardia and loss of variability, but does not harm the fetus

94
Q

What analgesic suppresses uterine contractions?

A

Ketorolac

95
Q

If an OB patient is having a section and is extremely anxious, what can be given?

A

Small dose fentanyl should not affect fetus

96
Q

What should be used in (obese) patients if partial epidural or inadequate spinal?

A

Ketamine 10mg IV every 5 minutes

-not associated with fetal depression or maternal depressed respirations at normal doses

97
Q

Other health care factors that are known teratogenic

A 
Radiation
Anesthesia
Some drugs
Hypoxia
Hypo/hyperglycemia
Poor nutrition
98
Q

Manifestations of tetragenicity:

A

Death
Structural abnormalities
Growth restriction
Functional deficiency

99
Q

What should be the focus of an anesthetic for a parturient?

A 
Avoid:
Hypoxemia
Hypotension
Acidosis
Hyperventilation
100
Q

At what MAC of ISO is uterine perfusion maintained?

A

1 - 1.5 MAC

101
Q

What results from higher concentrations of anesthetic gas?

A

Reduced uteroplacental blood flow
Fetal hypoxia
Decreased cardiac output
Fetal acidosis

102
Q

When do we start monitoring the fetus during surgery?

A

24 weeks (point of viability)

103
Q

What risk does the use of general anesthetic in the 1st and 2nd trimester carry?

A

Miscarriage

104
Q

What techniques should always be used for anesthesia during pregnancy?

A

Prophylaxis for aspiration
Left uterine displacement from 20 weeks on
Preoxygenation
RSI - do not ventilate

105
Q

What drug combinations are considered usually safe

A 
Propofol
Fentanyl
ISO (forane)
Succs
Rocuronium
Reversal (Neostigmine and Atropine)
106
Q

What about PaCO2 do you want to avoid?

A

Low PaCO2

107
Q

What about hypotension?

A

Treat aggressively

OB Test 2 (4 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions