Anesthesia Before & During Pregnancy, Anesthetic Complications

Question 1

_______ is the study of abnormal development or birth defects. Teratogens are substances that act to irreversibly alter growth, structure, or function of the developing embryo

Answer 1

Teratology

Question 2

Is fetal pH lower than maternal pH?

Answer 2

Fetal pH is lower than maternal pH, so that weak bases become more ionized in the fetus, thus limiting their transfer back across the placenta. Normally, the difference in pH is only 0.1 and this “ion trapping” is irrelevant, but fetal acidosis can significantly increase the fetal concentration of drugs such as local anesthetics.

Question 3

Is there a concern regarding breast milk and anesthesia?

Answer 3

Generally no, but the prolonged use of postoperative analgesics will increase the infant dose, and adverse effects have been described, particularly for opioids

Question 4

Which drugs have a high risk for adverse fetal effects?

Answer 4

Anticonvulsants and antidepressants have a high risk for adverse fetal effects.

Oral opioids such as codeine and tramadol are not recommended during breast-feeding.

Question 5

What antihypertensives should be avoided during pregnancy?

Answer 5

Angiotensin-converting enzyme inhibitors (ACEIs) and angiotensin receptor blockers (ARBs)

Question 6

ectopic pregnancy considerations

Answer 6

propofol or thiopental (ketamine or etomidate should be considered if patient is hemodynamically unstable)

Question 7

What is a A molar pregnancy?

Answer 7

A molar pregnancy is an abnormality of the placenta, caused by a problem when the egg and sperm join together at fertilization. Also called gestational trophoblastic disease (GTD), hydatidiform mole or simply referred to as a “mole”, this is a rare condition occurring in 1 out of every 1,000 pregnancies.

Two large-gauge peripheral intravenous catheters

Immediate availability of blood

Induction: etomidate if evidence of hemorrhage or hemodynamically unstable

Maintenance: inhalation or intravenous technique; avoid volatile agents if optimization of uterine contractility is required, and exercise caution with the use of a propofol infusion in hemodynamically unstable patients

Oxytocin infusion (6 to 15 IU per hour) after cervical dilation or after partial uterine evacuation

Question 8

Is Neuraxial anesthesia is an excellent choice for prophylactic cervical cerclage?

Answer 8

Yep

Question 9

Maternal considerations

Answer 9

Decrease in MAC
Increased sensitivity to neuraxial agents
Decreased plasma cholinesterase
Decreased protein binding (more free drug)
Limited drug information in parturients

Question 10

Fetal Considerations

Answer 10

Anesthetic agents deemed safe include: thiopental, morphine, meperidine, fentanyl, succinylcholine, NDMRs.

Limit nitrous oxide use but only if hypotension secondary to volatiles can be avoided

fetal heart rate and uterine activity should be monitored in women of 20 weeks GA or greater.

When organized uterine activity is detected a Beta agonist like ritodrine can be used as a tocolytic. Magnesium may also work

Benzodiazepines have been linked to congenital anomalies. Weeks 3-8 are most critical as that is when organogenesis occurs.

Question 11

Additional Considerations for Non-Obstetric Surgery in Parturients

Answer 11

Elective procedures should be postponed until 6 weeks after delivery.

The physiological effects of pregnancy are usually well established by 20 weeks gestational age.

Volatile agent may suppress preterm labor.

Regional anesthesia may have significant advantages in this patient population.