Obstetric Anesthesia II Flashcards

1
Q

When can systemic medications be used for labor pain relief?

A

When neuraxial analgesia is unavailable, refused, or contraindicated.

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

What are the disadvantages of using systemic medications for labor pain relief?

A
  • Often inadequate pain relief.
  • Risks of fetal and maternal respiratory depression.
  • Nausea and vomiting.
  • Decreased lower esophageal sphincter tone.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Why are controlled, randomized trials comparing neuraxial and IV analgesia in labor challenging to conduct?

A

High protocol failure rates.

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

What did a systematic review of studies involving over 9600 women comparing neuraxial analgesia to opiates find?

A
  • Neuraxial techniques offer better pain relief.
  • Reduced risk of fetal acidosis.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

How has the use of parenteral narcotics in early labor changed with the evolution of obstetric anesthesia?

A
  • Declined usage.
  • Early labor patients are now acceptable candidates for neuraxial analgesia.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Which Analgesics are used in the parturient?

A
  • Meperidine
  • Fentanyl
  • Butorphanol
  • Nalbuphine
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is the dose, onset, DOA, and PCA dosing for Meperidine (Demerol)?

A

25-50 mg IV (usual dose)
Onset: 5-10 min
DOA: 2-3 hr
PCA dose: 15 mg q10 min

Active metabolite that may last up to 3 days. Neonatal effect are most likely if delivery occurs between 1 and 4 hr after administration.

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

What is the dose, onset, DOA, and PCA dosing for Fentanyl?

A
  • Dose: 1-2 mcg/kg IV
  • Onset: 2-3 min
  • DOA: 45 min
  • PCA dose: 50 mcg/kg q10 min

Short-acting, no active metabolites, potent respiratory depressant for mother, minimal sedation and nausea.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is the dose, onset, DOA, and PCA dosing for Butorphanol?

A
  • Dose: 1-2 mg IV
  • Onset: 5 min
  • DOA: 2-3 hr
  • PCA: N/A

Sedating for mother, ceiling effect for both analgesia and respiratory depression, dysphoric reactions, or withdrawal symptoms in opioid-dependent patients can occur.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is the dose, onset, DOA, and PCA dosing for Nalbuphine?

A
  • Dose: 10 mg IV
  • Onset: 5 min
  • DOA: 2-3 hr

similar profile to butorphanol

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

What are some nonpharmacologic alternatives for labor pain relief?

A
  • Hydrotherapy.
  • Hypnotherapy.
  • Massage.
  • Movement.
  • Positioning.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What influences maternal satisfaction during childbirth more than the degree of pain endured?

A

Whether the birth event met the mother’s expectations.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is the role of an obstetric anesthesia provider in supporting laboring women?

A
  • To help women make informed choices that meet their expectations.
  • Ensuring the safety of both mother and infant.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is considered the best method of pain relief for labor and delivery?

A

Neuraxial analgesia.

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

What are common types of neuraxial anesthetics?

A
  • Epidural.
  • Combined spinal-epidural (CSE).
  • Spinal techniques.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What defines labor as a prerequisite for neuraxial analgesia?

A

Regular uterine contractions result in cervical dilation and effacement.

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

When should early initiation of neuraxial anesthesia be considered?

A
  • For parturients at increased risk of anesthetic or obstetric complications.
  • Examples: morbid obesity, severe scoliosis, and known difficult airway.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What are the obstetric indications for early placement of neuraxial anesthesia?

A
  • Multiple gestation pregnancies.
  • Severe preeclampsia.
  • Allows better positioning cooperation and time to confirm block function.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What are the absolute contraindications of neuraxial anesthesia?

A
  • Patient refusal.
  • Inability to cooperate.
  • Uncorrected severe hypovolemia.
  • Uncorrected coagulopathy or pharmacologic anticoagulation.
  • Elevated intracranial pressure due to a mass.
  • Infection at the insertion site.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What are some relative contraindications to neuraxial anesthesia?

A
  • Stable preexisting CNS disease.
  • Chronic severe headaches or back pain.
  • Untreated bacteremia.
  • Severe stenotic valvular lesions.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What should be considered for patients with preexisting conditions before neuraxial anesthesia?

A
  • Careful pre-anesthetic evaluation and consultation.
  • Assessing risks and benefits of the procedure.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Can patients with preexisting conditions safely receive neuraxial anesthesia?

A

Yes, with proper recognition and optimization of these conditions.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q
A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What technique is essential during the insertion of neuraxial anesthetics?

A

Strict aseptic technique.

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

What antiseptic should be considered the choice for neuraxial anesthetic placement?

A

Chlorhexidine gluconate in an alcohol-based solution.

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

What is often the easiest position for a laboring parturient during neuraxial anesthetic placement?

A
  • Sitting position.

Offers maximum interspace width.

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

What advantage does the lateral position offer during neuraxial anesthetic placement?

A

Reduces the incidence of intravascular catheter placement.

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

What is the patient’s position for Epidural anesthesia?

A
  • sitting up
  • Laying down (sideways)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

What are the characteristics of epidural analgesia for labor?

A
  • Popular, safe, and effective.
  • Provides labor analgesia.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

What advantage does the use of an indwelling epidural catheter provide?

A
  • Ability to produce a segmental block of varying density.
  • It can be adapted to the patient’s changing requirements.
31
Q

At which interspaces is an epidural for labor analgesia optimally inserted?

A
  • L2-L3 or L3-L4 interspace.
  • To block the T10-L1 dermatomes for first-stage labor analgesia.
32
Q

What is required for analgesia in the second stage of labor and subsequent repair?

A
  • Extension of the block to include the S2-S4 dermatomes.
  • Innervates the perineum and vagina.
33
Q

Why is the high cephalic spread of a neuraxial block a concern in obstetrics?

A
  • One of the most common causes of anesthesia-related maternal mortality.
34
Q

What is the purpose of a test dose in epidural analgesia?

A
  • To identify epidural catheters inadvertently inserted into the subarachnoid space or an epidural vein.
  • Aspiration for blood or CSF is essential after catheter placement and before each dose.
35
Q

What is a commonly used test dose for epidural analgesia?

A

3 mL of lidocaine 1.5% with epinephrine 1:200,000.

36
Q

What are the effects of the lidocaine test dose if administered in the subarachnoid space?

A
  • Produces a noticeable but manageable spinal anesthetic within 3 to 5 minutes.
  • There is no appreciable effect in the epidural space.
37
Q

What are the effects of lidocaine if administered intravascularly?

A
  • Early signs of modest systemic toxicity (e.g., circumoral numbness, lightheadedness, auditory changes).
  • Includes 15 mcg of epinephrine, increasing HR if given intravascularly in nonpregnant patients.
38
Q

What is the drawback of maintaining epidural analgesia with intermittent bolus administration?

A
  • Alternating periods of analgesia and pain.
  • Frequent provider interventions.
39
Q

What are common infusions used to maintain epidural analgesia?

A
  • Bupivacaine (0.0625%–0.125%) or
  • Ropivacaine (0.1%-0.2%)
  • With fentanyl (1–3 mcg/mL) or sufentanil (0.3–0.5 mcg/mL).
  • Infusion rates of 8 to 12 mL/hour.
40
Q

When should the epidural infusion be maintained during labor?

A
  • Through the transition to second-stage labor.
  • Provided block is stable, effective, and preserves adequate motor function.
41
Q

What is Patient-Controlled Epidural Analgesia (PCEA) and its advantages?

A
  • Allows parturients to self-administer bolus doses as needed.
  • Reduces unscheduled interventions, total drug dose, and lower extremity motor block.
  • Effective analgesia without sacrificing quality.
42
Q

What is the perceived advantage of the Combined Spinal-Epidural (CSE) technique?

A

Provides superior analgesia for labor and vaginal delivery.

43
Q

How does CSE combine the attributes of spinal and epidural techniques?

A
  • Spinal component: Effective, rapid-onset analgesia.
  • Epidural catheter: Prolongs analgesia and allows conversion to surgical level if needed.
44
Q

What methods are used for performing CSE?

A
  • Early technique: Spinal needle insertion/removal followed by epidural insertion.
  • Needle-through-needle technique: Spinal needle through the epidural needle.
45
Q

How is the spinal component of a CSE dosed?

A
  • With a lipid-soluble narcotic alone or in combination with isobaric bupivacaine.
  • Common for early first-stage labor: Fentanyl (15–25 mcg) or sufentanil (10 mcg).
46
Q

What percentage of deliveries are by cesarean in the United States?

A
  • Over 30% of all deliveries.
47
Q

What are the indications of Cesarean Delivery in the United States?

A
  • Cephalopelvic disproportion.
  • Nonreassuring fetal status, arrest of dilation.
  • Malpresentation.
  • Prematurity, prior cesarean, prior uterine surgery.
48
Q

What factors influence the choice of anesthesia for cesarean delivery?

A
  • Maternal status.
  • Urgency of surgery.
  • Condition of the fetus.
  • Patient’s desires.
49
Q

What are the advantages of neuraxial anesthesia for cesarean delivery?

A
  • Decreased risk of mortality (failed intubation, aspiration).
  • Better neonatal outcomes (less depressant agents).
  • Mother can be awake for delivery.
50
Q

What is the typical range of blood loss during cesarean delivery?

A

Between 500 and 1000 mL.

51
Q

Why is the visual estimation of blood loss during cesarean delivery often inaccurate?

A
  • Complicated by large volumes of amniotic fluid and variably saturated sponges.
  • Normal amniotic fluid volume: 300–1400 mL (average ~700 mL).
52
Q

What are the advantages of single-shot spinal anesthesia for cesarean delivery?

A
  • Rapid onset of action.
  • Denser block.
  • Requires less local anesthetic compared to epidural anesthesia.
53
Q

What dermatome level is required for effective anesthesia in cesarean delivery, and what are its potential effects?

A
  • T4 level.
  • It can cause profound sympathectomy, leading to maternal hypotension and potential fetal compromise.
54
Q

What measures are commonly used to minimize hypotension during spinal anesthesia for cesarean delivery?

A
  • Left uterine displacement.
  • Intravenous (IV) fluid administration.
  • Vasopressor use.
55
Q

What is the effective dose of hyperbaric bupivacaine for spinal anesthesia in cesarean delivery, and how long does it provide surgical anesthesia?

A
  • 0.75% 13 mg (ED95).
  • Provides 90 to 120 minutes of surgical anesthesia.
56
Q

What vasopressors are commonly used to treat maternal hypotension during spinal anesthesia?

A
  • Ephedrine.
  • Phenylephrine.
57
Q

How are opioids used in conjunction with hyperbaric bupivacaine for spinal anesthesia in cesarean delivery?

A
  • Added to provide intraoperative and postoperative analgesia.
  • Do not affect block height.
  • Examples: Fentanyl (10–20 mcg) or Sufentanil (2.5–5 mcg).
58
Q

When should oxytocin be administered during cesarean delivery under spinal anesthesia?

A

After the delivery of the placenta, as directed by the obstetrician.

59
Q

What are alternative methods for postoperative analgesia in cesarean delivery if intrathecal morphine is not an option?

A
  • Transversus abdominis plane blocks.
  • Quadratus lumborum blocks.
  • Used when neuraxial anesthesia is contraindicated or for patients under general anesthesia.
60
Q

What are the spinal bolus, Epidural bolus, and Epidural continuous infusion doses for BUPIVACAINE?

A
  • Spinal Bolus: 1.25- 2.5 mg
  • Epidural Bolus: 0.0625-0.125%
  • Epidural Continuous: 0.05-0.125%
61
Q

What are the spinal bolus, epidural bolus, and continuous epidural infusion doses for ROPIVACAINE?

A
  • Spinal Bolus: 2-3.5 mg
  • Epidural Bolus: 0.08-0.2%
  • Epidural Continuous: 0.08-0.2 %
62
Q

What are the spinal bolus, epidural bolus, and continuous epidural infusion doses for FENTANYL?

A
  • Spinal bolus: 15-25 mcg
  • Epidural bolus: 50-100 mcg
  • Epidural continuous: 1.5-3 mcg/mL
63
Q
A
64
Q

Converting Epidural Anesthesia to Cesarian Anesthetic

A
65
Q

What are the common complications of regional anesthesia?

A
  • Hypotension.
  • Nausea and vomiting.
  • Postdural puncture headache.
  • Local anesthetic systemic toxicity.
  • Accidental subdural injection.
  • Total spinal block.
  • Neurologic injuries.
66
Q

What causes total spinal anesthesia?

A
  • Excessive cephalic spread of local anesthetic in subarachnoid or epidural space.
  • Inadvertent large epidural dose into subarachnoid space.
  • Epidural catheter migration into subarachnoid space.
67
Q

What are the early signs of a total spinal block?

A
  • Rapid onset.
  • Dyspnea.
  • Difficult phonation.
  • Hypotension.
68
Q

What cardiovascular effect can a total spinal block have?

A
  • Bradycardia
  • From blockade of sympathetic innervation to the heart (T1-T4 segment).
69
Q

What is the initial treatment for total spinal block?

A
  • Vasopressors.
  • IV fluids.
  • Left uterine displacement.
  • Leg elevation.
  • Prepare for intubation if consciousness is lost or airway protection is compromised.
70
Q

What conditions should be considered in the differential diagnosis of total spinal block?

A
  • Anaphylactic shock.
  • Eclampsia.
  • Amniotic fluid embolism.
71
Q

Dermatomes

A
72
Q

In what situations might general anesthesia be indicated for cesarean delivery despite its disadvantages?

A
  • Better airway control and hemodynamic stability.
  • Useful in hypovolemic shock or maternal cardiac disease.
  • Urgent surgical delivery precluding neuraxial anesthetic placement.
  • Patient refusal or coagulopathy present.
  • As an alternative in failed neuraxial technique cases.
73
Q

Why has the use of neuraxial techniques become more prevalent than general anesthesia for cesarean delivery?

A

To reduce maternal mortality from airway complications.