Obstetrics

Question 1

A patient requires an emergency cesarean section. Which of the following is the MOST likely cause for rapid arterial oxygen desaturation during intubation?
a. decreased expiratory reserve volume
b. increased inspiratory reserve capacity
c. increased residual volume
d. decreased vital capacity

Answer 1

a. decreased expiratory reserve volume

Question 2

The parturient is at higher risk of these three things related to the airway:

Answer 2

difficult mask ventilation
difficult laryngoscopy
difficult intubation

Question 3

Factors that make airway management more complicated in the parturient include

Answer 3

increased Mallampatti score
upper airway vascular engorgement
narrowing of the glottic opening

Question 4

______ these factors hasten the onset of hypoxemia during apnea for the parturient.

Answer 4

increased oxygen consumption paired with a decreased FRC

Question 5

__________ increases minute ventilation up to 50% leading to the mother developing a mild compensated respiratory alkalosis.

Answer 5

Progesterone

Question 6

_______ falls below _________, which causes airway closure during tidal breathing.

Answer 6

Functional reserve capacity falls below closing capacity.

Question 7

Upper airway swelling in the parturient is te result of

Answer 7

increased progesterone, estrogen, and relaxin causing vascular engorgement and hyperemia
& increased extracellular volume

Question 8

Since the glottic opening is narrowed______ should be used.

Answer 8

a downsized endotracheal tube

Question 9

Airway edema is worsened by

Answer 9

preeclampsia, tocolytics, and prolonged Trendelenburg position

Question 10

What type of laryngoscope handle is recommended for large breasted women?

Answer 10

a short-handled laryngoscope (Datta handle)

Question 11

Why should nasal intubation be avoided in full term mothers?

Answer 11

the tissue in the nasopharynx is particularly friable because of hormonal changes and local edema

Question 12

Which hemodynamic variables increase during pregnancy?
a. heart rate
b. stroke volume
c. systemic vascular resistance
d. pulmonary artery occlusion pressure

Answer 12

A & B
SV is increased as a function of increased intravascular volume while heart rate is increased to satisfy higher metabolic demand

Question 13

_________ increases throughout pregnancy to support the growing fetus.

Answer 13

Maternal oxygen consumption

Question 14

What hemodynamic factors remain stable throughout pregnancy?

Answer 14

MAP & SBP

Question 15

What hemodynamic variables decrease during pregnancy?

Answer 15

DBP, SVR, and PVR

Question 16

Describe how dilutional anemia results in the pregnant patient.

Answer 16

plasma volume expansion outpaces new RBC production

Question 17

Pregnancy produces a ___________ that predisposes mothers to DVT

Answer 17

hypercoagulable state

Question 18

In the supine position, the gravid uterus compresses both the

Answer 18

vena cava and aorta leading to aortocaval compression

Question 19

Aortocaval decompression (left displacement of the uterus) should be used in

Answer 19

2nd and 3rd trimesters

Question 20

Describe how cardiac output is affected during the stages of labor.

Answer 20

1st stage: increases by 20%
2nd stage: increases by 50%
3rd stage: increases by 80%

Question 21

Describe causes of thrombocytopenia during pregnancy.

Answer 21

gestational thrombocytopenia- most common
hypertensive disorders of pregnancy
idiopathic thrombocytopenia

Question 22

Which factors are expected to increase during pregnancy?
a. creatinine clearance
b. lower esophageal sphincter tone
c. sensitivity to local anesthetics
d. MAC
e. Gastric pH
f. Urine glucose

Answer 22

creatinine clearance
sensitivity to local anesthetics
urine glucose

Question 23

Pregnancy causes ______ to decrease by 30-40% beginning at 8-12 weeks and is caused by increased progesterone.

Answer 23

MAC

Question 24

__________ remains unchanged before the onset of labor, but slows after labor begins.

Answer 24

Gastric emptying time

Question 25

Describe how pregnancy affects ICP

Answer 25

No change

Question 26

Describe what pregnancy does to epidural vein volume.

Answer 26

increases

Question 27

Describe the GI effects that pregnancy has on gastric volume, gastric pH, LES sphincter tone, and gastric emptying.

Answer 27

volume- increased pH- decreased sphincter tone- decreased gastric emptying- no change to decreased after labor begins

Question 28

Describe how pregnancy affects GFR, creatinine clearance, glucose in the urine, and BUN and creatinine.

Answer 28

GFR- increased creatinine clearance- increased glucose in urine- increased creatinine and BUN- decreased

Question 29

Describe how pregnancy affects uterine blood flow, serum albumin, and pseudocholinesterase.

Answer 29

uterine blood flow- increased serum albumin- decreased (higher free fraction of highly protein bound drugs) pseudocholinesterase- no meaningful effect on succinylcholine metabolism

Question 30

Uterine blood flow is: a. 20% of cardiac output b. 700 mL/min. c. not autoregulated d. reduced by phenylephrine

Answer 30

B & C it's 10% of the cardiac output

Question 31

Uterine blood flow is not autoregulated. It is dependent on

Answer 31

maternal MAP, cardiac output, and uterine vascular resistance

Question 32

Uterine blood flow increases up to _____ at term.

Answer 32

700-900 mL/min.

Question 33

_____________ is as efficacious as ________ in maintaining placental perfusion and fetal pH in healthy mothers.

Answer 33

phenylephrine; ephedrine

Question 34

Physiochemical drug characteristics that favor placental transfer include:

Answer 34

low molecular weight (<500 Daltons) high lipid solubility Non-ionized Non-polar

Question 35

Which drugs do NOT cross the placenta? (most do so it's easier to learn which drugs do not cross)

Answer 35

heparin, neuromuscular blockers, glycopyrrolate, and insulin

Question 36

Causes of reduced uterine blood flow include

Answer 36

decreased perfusion- maternal hypotension (sympathectomy, hemorrhage, aortocaval compression) increased resistance- uterine contraction, hypertensive conditions that increase UVR

Question 37

____________- can increase the concentration gradient, which leads to fetal ion trapping.

Answer 37

Fetal acidosis

Question 38

Which stage of labor begins with the onset of perineal pain? a. latent stage b. active stage c. first stage d. second stage

Answer 38

second stage

Question 39

________ begins with full cervical dilation and ends with the delivery of the newborn.

Answer 39

second stage

Question 40

______ begins with the delivery of the newborn and ends with the delivery of the placenta.

Answer 40

third stage

Question 41

_______ begins with cervical dilation with regular uterine contractions and ends with full cervical dilation (10 cm). It can be divided into the latent phase and active phase.

Answer 41

first stage

Question 42

______ is always considered a full stomach!

Answer 42

A laboring mother

Question 43

According to the ASA practice guidelines for obstetric analgesia, the laboring mother who is healthy may: _____________ throughout labor ___________up to the point a neuraxial block is placed

Answer 43

drink a moderate amount of clear liquids throughout labor eat solid food up to the point a neuraxial block is placed

Question 44

An epidural does not prolong

Answer 44

the first stage of labor and it does not increase the need for a C-section

Question 45

The latent phase of labor is

Answer 45

cervical dilation up to 2-3 cm

Question 46

______ occurs when labor does not follow the expected pattern. ________ may be required to help the labor progress.

Answer 46

Dysfunctional labor oxytocin