Brainscape's Knowledge GenomeTM

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


See full index

Maternal, Fetal, and Neonatal physiology > E2: Perinatal Pharm > Flashcards

E2: Perinatal Pharm Flashcards

1
Q

Describe the various disposition of drugs throguhout the compartments of the body following absorption

A

Absorption → Plasma Compartment

⇔Body Organs

⇔Liver

⇔Kidney

⇔Tissue Reservoir

⇔Site of Action

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

Describe the fluid compartment breakdown of the body

A

Total body vol: 30.25L (55% of BW)

→ Intracellular Fluid: 22L

→ Extracellular Fluid: 11L

→Intravascular Fluid (Plasma): 2.35L

→Extravascular Fluid: 8.65L

→Interstitial Fluid: 8.25L

→Transcellular Fluid: 0.4L

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

What is the Cmax?

A

The Cmax is the highest drug concentration observed in plasma after administration of a single Extravascular dose

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

What is the Tmax?

A

The Tmax is the time it takes to reach Cmax

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

What is T1/2?

A

T1/2 is the duration in which the plasma concentration of a drug falls by 50%

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

What is Vd?

A

Volume of Distribution (Vd) is the total space available in the body to contain the known amount of drug.
If a drug has a high Vd, it is widely distributed and attains a lower plasma concentration per the given dose.

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

Describe/draw the fates of a drug

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

What are the factors influencing the distribution of drugs in the fetus?

A
  1. Amount and type of Drug
  2. Membrane permeability, receptor function, & Placental enzymes
  3. Fetal circulation, pH, & body water compartment
  4. Gestational age
  5. Maternal Serum Binding Protein
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What are the pharmacokinetic parameters of absorption?

A
  • Intestinal Motility
  • Ventilation
  • Cardiac Output
  • Blood flow to skin
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What are the pharmacokinetic parameters of Distribution?

A
  • Plasma Vol.
  • Total Body water
  • Plasma Proteins
  • Body fat
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What are the pharmacokinetic parameters of Metabolism?

A
  • Hepatic Metabolism
  • Extrahepatic metabolism
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What are the pharmacokinetic parameters of Excretion?

A
  • Uterine BF
  • Renal BF
  • Glomerular Filtration Rate
  • Ventilation
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

How do the pharmacokinetic parameters of absorption change during pregnancy?

A

Intestinal Motility: Decreases

Ventilation: Increases

Cardiac Output: Increases

BF to skin: Increases

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

How do the pharmacokinetic parameters of Distribution change during pregnancy?

A

Plasma Volume: Increases

Total Body water: Increases

Plasma proteins: Decrease

Body fat: Increases

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

How do the pharmacokinetic parameters of Metabolism change during pregnancy?

A

Both Hepatic & Extrahepatic metabolism is variable

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

How do the pharmacokinetic parameters of excretion change during pregnancy?

A

Uterine BF: Increases

Renal BF: Increases

GFR: Increases

Ventilation: Increases

17
Q

Describe the characteristics of a molecule most likely to pass the placental barrier in terms of;

  1. Solubility
  2. Charge
  3. Protein-binding
  4. Molecular Mass
A
  1. Fat-soluble (hydrophobic)
  2. Uncharged
  3. Low amount of protein-binding > higher free molecules
  4. Low molecular mass
18
Q

What are the consequences of the delayed gastric emptying & increased gastric pH during pregnancy on drug disposition?

A

Bioavailability of drug is altered and delayed time to peak levels following oral administration

19
Q

What are the consequences of the increased Cardiac Output during pregnancy on drug disposition?

A

Increased CO>

Increased hepatic BF > Increased elimination of SOME drugs

20
Q

What are the consequences of the increased total body water (TBW)/ Extracellular Fluid during pregnancy on drug disposition?

A

Altered Drug disposition> increased Vd for hydrophilic drugs

21
Q

What are the consequences of the Increased fat compartment during pregnancy on drug disposition?

A

Increased body fat >

Decreased elimination of fat-soluble drugs > increased Vd for hydrophobic drugs

22
Q

What are the consequences of the Increased Renal BF & GFR during pregnancy on drug disposition?

A

Increased RBF & GFR>

Increased Renal Clearance

23
Q

What are the consequences of the decreased plasma albumin concentration during pregnancy on drug disposition?

A

Decreased Plasma Albumin conc. >

Increased free fraction of drug

24
Q

What are the consequences of the altered CYP450 & UGT activity during pregnancy on drug disposition?

A

altered oral bioavailability & hepatic elimination.

25
Q

How does plasma volume change during pregnancy?

Describe the pharmacokinetic result

A

50% increase in plasma volume & body water:

  • Water soluble (hydrophilic) drugs are more diluted
  • Dosage requirements may increase
  • *This effect may be offset by other changes
26
Q

How does body weight/fat change during pregnancy?

Describe the pharmacokinetic result

A

Body weight/fat increases by approximately 14kg

  • Fat-soluble (hydrophobic) drugs are distributed more widely
    • Tend to linger in the body longer
27
Q

How does Serum Albumin change during pregnancy?

Describe the pharmacokinetic result

A

Decrease in Serum Albumin:

  • More free drug is available
  • Given dose is likely to produce a greater affect than it would in a non pregnant woman.
28
Q

How does Renal BF & GFR change during pregnancy?

Describe the pharmacokinetic result

A

Both RBF & GFR Increase:

  • Increased excretion of drugs by kidneys
  • *Late pregnancy: Increased size of uterus constricts RBF in supine position
    • Results in decreased excretion & prolonged effects of renally excreted drugs
29
Q

From arterial blood, describe the potential locations of action, to venous blood.

A

Arterial:>

  • Adipose
  • Bone
  • Brain
  • Heart
  • Kidney
  • Muscle
  • Liver
  • Spleen > Liver
  • Gut > Liver
  • Placental-fetal unit
30
Q

In general, what are the Physiochemical properties of a drug that influence it’s transfer across the placenta?

A

Physiochemical:

  • Solubility: Lipid vs water
  • Charge: (ionization)
  • Molecular Mass
  • Protein Binding char.
31
Q

Descibe how placental flow can affect the transfer of a drug across the placenta

A

Compounds that alter BF alter maternal drug dispo. and placental transfer

32
Q

What is placental metabolism’s role in drug transfer across the placental barrier?

What are some examples of Placental enzymes?

A

Placental metabolism is relatively minor relative to hepatic metabolism.

Phase I enzymes: Dealkylation, hydroxylation, demethylation

  • Cytochrome P450 (w/ various isoforms)
  • Changes w/ gestational age

Phase II enzymes: Conjugation

  • Glutathione-S-Transferases
  • Epoxide Hydrolase
  • Sulphotransferases
  • N-AcetylTransferase
  • Glucuronyl Transferase

Maternal, Fetal, and Neonatal physiology (13 decks)

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