Brainscape's Knowledge GenomeTM

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


See full index

My OB > Quiz 2 > Flashcards

Quiz 2 Flashcards

1
Q

1st stage – pain source is mainly _________ segment from contractions (_____ dermatomes)

A

lower uterine

T10-L1

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

2nd stage – source is __________ via ____________ (_____ dermatomes)

A

perineal structures

pudendal nerve

S2-S4

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

Meperidine (Demerol)

A
  • Dose 25-50 mg IV.
  • Onset 5 min.
  • Kinetics Half-life 18-23 hrs in neonate, also has active metabolites.
  • Causes frequent N/V.
  • Neonatal respiratory depression unlikely if given less than 1 hour prior to delivery.
  • Contraindicated in pt with seizure d/o or renal failure.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Nalbuphine (Nubain)

A
  • Mu opioid antagonist, kappa agonist.
  • Has ceiling effect on resp depression but no real large difference in side effects.
  • Dysphoria common.
  • Used to treat opioid induced pruritis (5-10 mg iv q 6 H prn)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Butorphanol (Stadol)

A
  • Dose 1-2 mg.
  • Some reports suggest better analgesic profile than fentanyl.
  • Sedation common.
  • Ceiling effect on resp depression.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

dose limit on volatile anesthetics?

A

0.5 MAC

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

Paracervical block

A
  • 1st stage of labor.

- Technique: 5cc of local injected submucosally at 3 and 9 o’clock position beside cervix.

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

Pudendal block

A
  • Used for 2nd stage of labor.
  • Good for certain patients with contraindication for neuraxial block.
  • Technique: Needle is placed bilaterally via transvaginal approach under the ischial spines.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Local anesthetics: Esters

A
  • Ester derivatives of para-aminobenzoic acid (PABA).
  • Metabolized by plasma cholinesterase.
  • Metabolite PABA is a known allergen.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Local anesthetics: Amides

A
  • Amide linkage, metabolized by liver.

- No PABA -> allergic reactions are rare.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Local anesthetics: Lipid Solubility

A
  • Influences potency – more lipid soluble agents can pass more easily through the lipoprotein nerve membrane.
  • Increasing lipid solubility enhances placental diffusion.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Local anesthetics: Protein Binding

A
  • Influences duration – increased protein binding correlates to longer duration.
  • High protein binding decreases placental transfer.
  • Α1-acid glycoprotein (high affinity, low capacity)
  • Albumin (low affinity, high capacity)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Local anesthetic site of action is ___________________ sodium channel

A

neuronal cell membrane

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

The closer pKa is to physiological pH -> more LA in nonpolar form -> ______ onset

A

faster

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

Artificially raise pH so it is closer to pKa -> add __________

A

bicarbonate

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

Temperature affects onset, with warmed LA ________ onset time

A

reduces

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

Increasing doses of LA ->_____ onset, ______ duration

A

faster

longer

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

Pain receptors

A

A-delta

C fibers

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

LA For labor epidural analgesia:

A
  • Bupivacaine
  • Ropivacaine
  • Lidocaine
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

LA For operative epidural anesthesia

A
  • Lidocaine

- 2-chloroprocaine

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

LA For spinal anesthesia

A
  • Tetracaine

- Bupivacaine

22
Q

2-Chloroprocaine

A

Dose:
15-25cc of 3% 2-chloroprocaine for epidural c-section (may require re-dosing, give 5cc at a time.

Properties

  • The only ester local used in epidural space
  • Rapid onset, very short duration
  • Lot of motor block
  • Low risk of toxicity, very rapidly metabolized in blood by pseudocholinesterase
23
Q

Bupivacaine

A

Dose for labor epidural:
initial bolus 15-20 mg (e.g., 7.5-10 cc 0.2% bupivacaine), infusion- 8-12 mg/hr (e.g., 8-12 cc/hr of 0.1% solution).

  • Long duration, less motor block than most other agents.
  • Produces refractory v-tach/v-fib if large IV dose given.
24
Q

Levobupivacaine:

A
  • L-isomer of bupivacaine

- Less cardiotoxic

25
Q

Ropivacaine:

A
  • Less cardiotoxicity than even levo in animal studies.
  • May be about 25% less potent than bupivacaine.
  • Not approved for spinal (neither is levo).
26
Q

For obstetrics lumbar level is best to cover __________ dermatomes

A

T-10 thru S4

27
Q

Contraindications to neuraxial blockade

A
  • patient refusal
  • Infection at the site of injection.
  • Coagulopathy (liver failure, anticoagulants, HELLP syndrome, thrombocytopenia etc.).
  • Intracranial mass lesion.
  • Aortic stenosis.
  • Existing spinal or neurological pathology.
  • Hemodyamic instability
28
Q

Epidural space on avg identified ____ cm deep

A

4.75

29
Q

Local Anesthetic Toxicity - CNS

A 
Tinnitus
Light-headedness
Metallic taste
Circumoral numbness
Convulsions
Loss of consciousness
Respiratory arrest
30
Q

Increased ______ and _______ lower seizure threshold

A

PaCO2

acidosis

(Acidosis decreases protein binding -> more free LA)

31
Q

Local Anesthetic Toxicity - CVS

A
  • Inhibition of cardiac sodium channels.
  • Decrease rate of depolarization in Purkinje’s fibers and ventricular muscle.
  • Decrease duration of action potential and effective refractory period.
  • Increased toxicity to bupivacaine and cocaine with pregnancy.
32
Q

Intrallipid dosing for LAST

A
  • 1.5 mL/kg as an initial bolus, followed by
  • 0.25 mL/kg/min for 30-60 minutes
  • Bolus could be repeated1-2 times for persistent asystole
  • Infusion rate could be increasedif the BP declines
33
Q

Preterm labor

A

regular uterine contractions occurring at least q10 min resulting in cervical change prior to 37 weeks

34
Q

Low birth weight (LBW)

Very low birth weight (VLBW)

A

any infant < 2500g at birth

any infant < 1500g

35
Q

Survival can increase ____ each DAY btw 25-26 wks

A

~5%

36
Q

C-section is proven safer in PTL with _____ presentation

A

breech

37
Q

Tocolytic Therapy criteria

A

Gestational age 20-34 wks, EFW < 2500 g, absence of fetal distress

38
Q

Tocolytic Therapy: Methylxanthines

A
  • Aminophylline
  • Phosphodiesterase – increase intracellular cAMP -> uterine muscle relaxation.

Narrow therapeutic margin and frequent toxic side effects limit clinical use.

39
Q

Tocolytic Therapy: Calcium Channel Blockers

A

-Nifedipine

Myometrium contractility related to free calcium concentration: dec.Ca2+ -> dec. contractility.

Maternal side effects:
-Hypotension, tachycardia, dizziness, palpitations
-Facial flushing
-Vasodilation, peripheral edema
-Myocardial depression, conduction defects
-Hepatic dysfunction
-Postpartum hemorrhage
-Fetal side effects
-Decreased UBF -> fetal hypoxemia and fetal acidosis

40
Q

Tocolytic Therapy: Prostaglandin Synthetase Inhibitors

A

-Indomethacin, Sulindac
-Mechanism of action: dec. cyclooxygenase -> dec. prostaglandin

Maternal side effects:
-Nausea
-Heartburn
-Transient dec. platelet aggregation -> bleeding
-Primary pulmonary HTN

Fetal side effects:
-Crosses placenta
-Premature closure of ductus arteriosus
-Persistent fetal circulation
-Renal impairment, transient oliguria

41
Q

Magnesium treatment ranges, treatment for toxicity?

A

Normal treatment range is 4-7 mg/100 mL

Toxicity at greater values:

  • 8-10 = loss of deep tendon reflexes
  • 10-15 = respiratory depression, cardiac conduction defects (wide QRS, inc P-R interval)
  • 20+ = cardiac arrest

Tx: calcium gluconate or CaCl

42
Q

Tocolytic Therapy: Beta adrenergic agonists

A

Terbutaline, Ritodrine

Direct stimulation of β-adrenergic receptors in uterine smooth muscle -> inc. cAMP -> uterine relaxation

43
Q

Risk factors for Beta adrenergic agonist Pulmonary Edema

A
  • Increased IVF administration
  • Multiple gestation
  • Tocolysis greater than 24 hrs
  • Concomitant magnesium therapy
  • Infection
  • Hypokalemia
  • Undiagnosed heart disease
44
Q

Review slide 21-24 on OB4

A

.

45
Q

Signs and Symptoms of uterine rupture, most reliable sign?

A
  • Sudden abdominal pain despite functioning epidural
  • Vaginal bleeding
  • Hypotension
  • Cessation of labor
  • Fetal distress – most reliable sign
46
Q

Increases risk of uterine rupture

A
  • Previous uterine surgery
  • Trauma
  • Multiparity
  • Uterine anomaly
  • Oxytocin
  • Placenta percreta
  • Tumors
  • Macrosomia
  • Malposition
47
Q

Greatest chance of uncomplicated spontaneous vaginal delivery with:

A

vertex presentation, flexed c-spine (chin to chest), occiput anterior (face down).

48
Q

Post-Maturity complications

A
  • Dec. uteroplacental blood flow  fetal distress
  • Umbilical cord compression due to oligohydramnios
  • Meconium staining of amniotic fluid
  • Inc. incidence of macrosomia, shoulder dystocia
49
Q

Intrauterine Fetal Demise (IUFD) Causes

A
  • Chromosomal abnormalities
  • Congenital malformations
  • Multiple gestation
  • Infection
  • Cord accidents
  • Placental factors
  • Maternal immunological or thyroid disease
  • Isoimmunization
  • Maternal trauma
50
Q

Umbilical cord length concerns

A

<30 cm risks compression, constriction, rupture.

>72 cm risks cord entanglement

My OB (4 decks)

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