Maternal Physiology

Question 1

How does TBW change in pregnancy?

Answer 1

Increase- 6.5 L to 8.5 L

Chronic volume overload

Question 2

Increase in what blood components lead to increased TBW?

Answer 2

Plasma volume

RBC mass

Question 3

What happens to serum sodium levels during pregnancy?

Answer 3

Decrease

Water retention > Na retention

Question 4

What is the lower limit for normal serum Na?

Answer 4

135 mmol

131 in pregnancy- drops 3-4 mmol

Question 5

ANP/BNP become elevated during pregnancy, can BNP still be used to screen for CHF?

Answer 5

Yes

Increases is much greater in CHF than the normal physiologic response to pregnancy

Question 6

What accounts for the dilutional anemia seen in pregnancy?

Answer 6

Plasma volume increases more than RBC mass

Question 7

What is responsible for decreased systemic vascular resistance in pregnancy?

Answer 7

Progesterone

Question 8

In what position is a pregnant woman’s CO greatest?

Answer 8

Left lateral position

Question 9

Low birth weight is associated with women who do large amounts of standing work, what is this attributed to?

Answer 9

Decreased CO

Question 10

Blood flow increases to what organs during pregnancy?

Answer 10

Kidneys
Uterus, breast
Skin

Question 11

What changes are seen on CXR in a pregnant woman?

Answer 11

Flattened left heart border
Prominent pulmonary vasculature
Heart position more horizontal
Elevation of diaphragm

Question 12

What changes does pregnancy have on pulmonary gas exchange?

Answer 12

RR no change
TV increase
Hyperventilation- progesterone
PaCO2 decreases
PaO2 increases
pH increases
Bicarb decreases

Question 13

What does increased TV during pregnancy result in?

Answer 13

Increased O2 uptake

Increased minute ventilation = RR*TV

Question 14

What happens to forced viral capacity during pregnancy?

Answer 14

Remains unchanged

Question 15

What happens to ERV during pregnancy?

Answer 15

Decreased

Due to elevated diaphragm

Question 16

A pregnant woman has a PCO2 of 40, what is this a sign of?

Answer 16

Impending respiratory failure

Should be low due to hyperventilation

Question 17

What term is used to describe the physiologic urinary tract changes during pregnancy?

Answer 17

Relative hydronephrosis of pregnancy- vasculature, interstitial volume, urinary dead space (dilation of renal pelvis, calyces, ureters)

Question 18

When does relative hydronephrosis resolve?

Answer 18

Week 6 postpartum

Question 19

What hormone is responsible for relative hydronephrosis of pregnancy?

Answer 19

Progesterone- SM relaxation

Question 20

Aside from progesterone what else cause relative hydronephrosis of pregnancy?

Answer 20

Mechanical compression due to enlarging uterus

Question 21

How can relative hydronephrosis of pregnancy make interpretation of urinary images difficult?

Answer 21

More difficult to evaluate urinary tract obstruction

Ultra sound

Question 22

Define calculus.

Answer 22

Stone

Question 23

Relative hydronephrosis increases the risk of what infection?

Answer 23

Pyelonephritis- urinary stasis

Question 24

What is a normal GFR?

Answer 24

100 mL/min

Question 25

What measurement approximates GFR?

Answer 25

Creatinine- slight overestimate

Question 26

What is the lower limit of normal for CRCL?

Answer 26

97 M | 88 W

Question 27

What changes do you expect to see in a pregnant woman's BUN and Cr?

Answer 27

Both decreased | Result of increased GFR + increased plasma volume

Question 28

A woman has chronic renal insufficiency, what effect can a pregnancy have on her disease?

Answer 28

1/3 in women may have worsening

Question 29

What is physiologic anemia of pregnancy?

Answer 29

Hemodilution | Plasma volume>RBC mass

Question 30

What causes increased risk for intravascular coagulation during pregnancy?

Answer 30

Virchow's triad | stasis, endothelial damage, changes in clotting factors

Question 31

What effect does pregnancy have on PT/PTT/thrombin time?

Answer 31

Drop slightly (still normal range)

Question 32

Where do most DVTS occur? Where does most pyelonephritis occur? (During pregnancy)

Answer 32

DVT- 90% L | Pyelonephritis- 90% R

Question 33

What is the standard of care for diagnosis DVT?

Answer 33

Doppler US

Question 34

What is the treatment for DVT during pregnancy?

Answer 34

LMW heparin

Question 35

Nausea and vomiting of pregnancy complicates 70% of pregnancies. There are many medicines and alternative therapies, what vitamin seems to benefit women?

Answer 35

Vitamin B6

Question 36

What is hyperemesis gravidarum?

Answer 36

``` Refractory nausea/vomiting Associated with: Weight loss Dehydration Ketonemia Electrolye imbalances ```

Question 37

What is hyperemesis gravidarum associated with?

Answer 37

Increased levels of hCG | Hyperthyroidism

Question 38

Hyperpigmentation is seen in 90% of pregancies, what hormone is responsible for these changes?

Answer 38

hCG | linea nigra, areolae, nipples, genital skin, axillae, melasma