Ex 3 - AC for pregnant patients, C-sections; neonatal or pediatric patients

Question 1

When do we use anesthetics in pregnant patients?

Answer 1

For delivery (C sections or manual)

For emergency procedures

Question 2

CV changes w/anesthesia

Answer 2

1. Increased Blood Volume
   - plasma > RBC
   - “anemia” (PCV 30-35%)
   - related to # of fetuses
2. Increased CO (40%)
3. Compensatory CV reflexes delayed
4. Uteroplacental perfusion is PRESSURE DEPENDENT!
   - hypotension = dec fetus perfusion

**Always monitor BP

Question 3

Respiratory changes

Answer 3

1. Pregnant uterus displaces the diaphragm
   - dec TLC and FRC
2. O2 consumption increased 20%
3. Inc P4 –> sensitivity to PaCO2
4. Inc risk of hypoxemia
   * **Preoxygenate patients!

Question 4

CNS changes

Answer 4

1. Anesthetic requirement decreased by 25-40%

2. Increased sensitivity to anesthetics –> risk of Overdosing!

Question 5

GI changes

Answer 5

1. Delayed gastric emptying
2. Decreased esophageal sphincter tone
   * risk of regurgitation and aspiration
   * *need to induce rapidly and protect the airway asap

Question 6

Fetal physiology

Answer 6

1. Some drugs can cross BBB into the placenta
2. Fetal blood supply has low PaO2
   - fetal Hb has higher affinity for O2

Question 7

Pregnant patient - Anesthesia Recommendations

Answer 7

1. Correct any deficits in circulating volume
   - correct electrolytes (Ca++)
2. Prooxygenate
3. Rapid induction/secure airway
   - risk of regurgitation/aspiration
4. Minimize dose
5. Minimize time
6. Have help to resuscitate neonates (1:1)
7. Maintain mom’s BP

Question 8

Premedication

Answer 8

1. Small animals
   * opioids and anticholinergics
2. LA
   * a2-agonists
3. Ruminants/camelids
   * Benzodiazepines or no premed

Question 9

Induction agents

Answer 9

Usually IV better than IA

1. SA
   * propofol (and alfaxalone)
   * Etomidate (or fentanyl) in special cases
2. LA
   * Ketamine +/- propofol (benzo)

Question 10

How much time do you give for drug redistribution

Answer 10

~15 mins

Question 11

Is IA good for induction?

Answer 11

NO!

Its stressful, prolonged, risk of regurgitation & aspiration, severe CV and respiratory depression

Question 12

Inhalant Anesthesia

Answer 12

Iso, sevo, or desflurane

low dose, IPPV, avoid nitrous oxide

Question 13

Post-op pain

Answer 13

Line (incision) block

Morphine epidural

Systemic opioids

NSAIDS

Question 14

Neonatal Resuscitation - I

Answer 14

• Remove placental membranes
• Clear oropharynx of secretions
• bulb syringe or gentle suction
• don’t swing neonate (obvi)
• Antagonize drugs
• sublingual or into umbilical vein

Question 15

Neonatal Resuscitation - II

Answer 15

• Rub chest vigorously
• O2 and heat
• intubate if not breathing
• acupuncture at GV 26
  Doxapram?
• increases O2 consumption but not in hypoxemia

Question 16

Neonate - concerns

Answer 16

1. dec ability to metabolize drugs
2. Hypoglycemia
3. Hypothermia
4. Bradycardia
5. Hypotension
6. Hypoventilation/atelectasis