OB

Question 1

What are the classifications of the hypertensive disorders in pregnancy (toxemia of pregnancy; pregnancy induced hypertension)?

Answer 1

gestational hypertension
preeclampsia (1- preeclampsia without severe features, 2- severe preeclampsia/eclampsia)
chronic hypertension
chronic hypertension with superimposed preeclampsia

Question 2

Define gestational diabetes

Answer 2

gestational hypertension, or pregnancy induced hypertension, is blood pressure of 140/90 and above in an otherwise healthy woman after the 19th week of gestation

Question 3

Define eclampsia (preeclampsia with severe features)

Answer 3

Eclampsia is present if seizures or coma occur in the syndrome of pregnancy induced hypertension. Eclampsia is therefore defined as preeclampsia with severe features.

Question 4

What are the risk factors for preeclampsia?

Answer 4

risk factors include: chronic renal disease, chronic hypertension, obesity, nulliparity, family history of preeclampsia, and advanced maternal age

Question 5

What is the cause of preeclampsia?

Answer 5

Abnormal placental implantation. This abnormal placenta releases vasoactive substances causing dysfunction of the maternal vasculature

Question 6

What is the drug of choice for seizure prophylaxis in a patient with preeclampsia? Why?

Answer 6

Magnesium sulfate is the drug of choice. It’s 50% more effective in preventing new onset and recurrent seizures than other commonly used anti convulsants.

Question 7

The patient with preeclampsia is in danger of developing serious complications. Name eight serious complications.

Answer 7

1) pulmonary edema
2) airway obstruction
3) placental abruption
4) cerebral hemorrhage
5) cerebral edema
6) DIC
7) HELLP syndrome
8) renal failure
9) CHF

Question 8

List medications used to blunt the hemodynamic response to laryngoscopy and intubation during induction of general anesthesia.

Answer 8

labetalol, esmolol, Nitroglycerin, sodium nitroprusside and remifentanil

Question 9

why is hydralazine a commonly used antihypertensive in preeclampsia?

Answer 9

it’s a vasodilator that also increases uteroplacental flow and renal blood flow. nitroglycerin and labetalol are also commonly used

Question 10

is regional anesthesia (epidural, spinal, CSE) contraindicated in preeclamptic patients?

Answer 10

provided there is no severe clotting deficit or plasma volume deficit, regional anesthesia can be safely used.

Question 11

what three anesthetic considerations must be taken in the parturient receiving magnesium sulfate?

Answer 11

1) causes prolong duration and intensity of nondepolarizing muscle neuromuscular blockade
2) causes uterine vasodilation causing postpartum uterine atony and hemorrhage
3) interacts with calcium entry blocking agents

Question 12

Once the fetus and placenta are delivered the mother is no longer at risk for complications of preeclampsia: true or false

Answer 12

false. pulmonary edema, stroke, embolism, airway obstruction, and seizures are a significant risk postpartum. severe preeclampsia, HELLP, and eclampsia can present for the first time in the postpartum period sometimes as late as four weeks after delivery

Question 13

Which drugs commonly used in anesthesia readily cross the placenta?

Answer 13

Most drugs, including many anesthetics, readily cross the placenta. These include: atropine, scopolamine, beta blockers, nitroprusside, nitroglycerin, diazepam, midazolam, propofol, ketamine, etomidate, thiopental, halothane, isoflurane, desflurane, nitrous oxide, local anesthetics, opioids, and ephedrine.

Question 14

Which medications used commonly during anesthesia do not cross the placenta and would need to be given directly into the fetal vein?

Answer 14

glycopyrrolate, heparin, depolarizing and nondepolarizing muscle relaxants, and phenylephrine do not cross the placenta and would need to be given directly into the fetal vein

Question 15

What are the four key factors that influence the rate of drug diffusion to the fetus?

Answer 15

1) physiochemical characteristics of the drug
2) dose and mode of administration
3) placental maturation
4) hemodynamic events within the fetomaternal unit

Question 16

Which is more lipophilic, the ionized or non ionized form of a drug?

Answer 16

non-ionized

Question 17

What is the effect of intravenous lidocaine on uterine blood flow?

Answer 17

All local anesthetics can reduce uterine blood flow at high plasma concentrations. High doses of IV lidocaine cause uterine arterial vasoconstriction and increased uterine tone

Question 18

Magnesium sulfate is a commonly used drug in pregnancy. Name three advantageous effects of magnesium sulfate in pregnancy

Answer 18

tocolysis
anti-convulsant
fetal neuroprotective agent

Question 19

Why is sodium bicarbonate routinely added to pre-packaged lidocaine with epinephrine for epidural anesthesia prior to cesarian section?

Answer 19

Alkalization of the local anesthetic hastens the onset of neural blockade and improves the quality of the block. Commercial preparations of local anesthetic, especially those containing epinephrine, are acidic. Adding sodium bicarbonate increases the amount of drug in the lipid soluble form thus increasing the rate of diffusion across lipid membranes. Sodium bicarb cannot be added to bupivacaine as it will precipitate

Question 20

What is the impact of adding epinephrine to local anesthetics used for epidural anesthesia?

Answer 20

During cesarian section, adding vasoconstrictors such as epinephrine to a local anesthetic prolongs the duration of the block, increases the intensity of the block, and decreases systemic absorption

Question 21

when is ketamine used for cesarian section? specify the dose

Answer 21

Ketamine 1 mg/kg is preferred for induction if the mother is hypovolemic due to its hypertensive effects. The maximum dose of ketamine for RSI of the parturient is 1 mg/kg. At higher doses, ketamine increases uterine tone and could endanger the fetus. Ketamine crosses the placenta due to its high lipid solubility. Ketamine at doses of 0.25-0.50 mg/kg IV produce rapid analgesia for labor and delivery. Ketamine given too close to delivery can cause respiratory depression and muscular hypertonicity resulting in lower apgar scores

Question 22

Besides induction of labor, what else is oxytocin routinely used for an obstetric anesthesia?

Answer 22

Oxytocin is the first line treatment for uterine atony. Oxytocin stimulates uterine smooth muscle and is routinely given intravenously. Immediately after delivery, rapid doses can cause hypotension. Prolonged infusions can lead to hyponatremia, fluid retention, and neurologic dysfunction. In the non preeclamptic patient, an ergo alkaloid (methergine) is next line therapy followed by prostaglandins (hemabate).

Question 23

Obese parturient’s are at increased risk for what 10 complications?

Answer 23

1) gestational hypertension
2) gestational diabetes
3) preeclampsia
4) infection
5) thromboembolism
6) stillbirth
7) fetal demise
8) difficult vaginal delivery
9) cesarian delivery
10) difficult airway
the fetus is at risk for macrosomia, shoulder dystocia, and congenital anomalies

Question 24

What is the preferred method of pain relief for the obese parturient?

Answer 24

early placement of continuous neuraxial analgesia

Question 25

which trimester is the safest to provide non obstetric surgery an anesthesia for the parturient?

Answer 25

the second trimester is the safest

Question 26

what is the most common cause of maternal death during obstetric general anesthesia?

Answer 26

hemorrhage

Question 27

Describe the use of a paracervical block during labor and delivery.

Answer 27

A paracervical block placed by obstetrician has fallen out of favor due to the high incidence of fetal asphyxia, fetal bradycardia, and systemic anesthesia toxicity. If used, a bilateral paracervical block will effectively block impulses to the cervix and uterus during the first stage of labor. It is not effective during the second stage of labor.

Question 28

What apgar score signifies mild to moderate depressed function? What noninvasive interventions can be used in this instance if the heart rate is above 100?

Answer 28

apgar scores of 3-7 signifies mild to moderate depressed function. Keep the neonate warm and dry. stimulate. Administering O2 by face mask without positive pressure ventilation can improve neonates Apgar score.

Question 29

List two actions that should be taken if the newborn’s heart rate falls below 100.

Answer 29

begin positive pressure face mask ventilation and spO2 monitoring

Question 30

What intervention is recommended when the neonate’s heart rate falls below 60?

Answer 30

Intubate if not already done. Continue positive pressure ventilation and begin chest compressions and cardiac monitoring. If heart rate below 60 persists, epinephrine is indicated.

Question 31

what is an EXIT procedure and what are the anesthetic considerations?

Answer 31

EXIT stands for ex utero intrapartum procedure. This procedure involves surgical correction of a fetus during partial delivery. It’s indicated in instances where the fetus would not survive surgery after separation from uteroplacental support (large fetal neck mass, reversal of tracheal occlusion from clips placed for congenital diaphragmatic hernia repair). Anesthetic considerations: maintain uterine relaxation during fetal surgery and provide anesthesia for both mother and fetus. Volatile agents and IV narcotics that cross the placenta are used. Usually two anesthesia teams are needed. After surgical correction is completed the fetus is delivered.

Question 32

what are the two leading causes of peripartum hemorrhage?

Answer 32

1) uterine atony

2) placenta accreta

Question 33

What can be done to reduce the risk of inadvertent intravascular injection of local anesthesia when dosing an epidural catheter?

Answer 33

The use of small divided doses of drug can greatly reduce the risk of a more serious local anesthetic overdose. Even properly placed catheters can migrate into a vein with prolonged use. Epidural doses of lidocaine an chloroprocaine given intravascularly will result in seizures

Question 34

List 7 interventions in the treatment of local anesthetic toxicity in the obstetric patient undergoing epidural anesthesia

Answer 34

1) early recognition 2) prevention of the progression of the reaction 3) maintenance of oxygenation 4) support the circulation 5) treatment of cardio toxicity 6) treatment of local anesthetic induced arrhythmias 7) assess the condition of the fetus as soon as possible after seizures are observed

Question 35

While caring for a parturient, concern arises for the well being of the fetus. The fetal heart rate tracing is indeterminate. The obstetrician employs digital stimulation of the fetal scalp and subsequent fetal heart rate accelerations are seen. What information does this suggest?

Answer 35

this gives reassurance that fetal acidosis is unlikely

Question 36

name five anatomic or physiologic changes that can lead to a difficult airway in the obstetric patient

Answer 36

1) fluid retention leading to airway edema
2) decreased FRC with an increase in O2 consumption (by 60%) resulting in a more rapid hypoxemia after induction
3) breast enlargement impeding laryngoscopy
4) dentition impeding view
5) need for RSI

Question 37

Your patient has aortic stenosis and is being prepared for an emergency cesarian section. The patient has not been adequately hydrated and hypotension is a major concern. Which anesthetic will you use?

Answer 37

General anesthesia is the gold standard in severe or symptomatic aortic stenosis. Hypotension is most common with a spinal anesthetic, less common with epidural anesthetics, and modestly less common with a regional technique. General anesthetic is associated with the least likelihood of hypotension and adequate maintenance of SVR