Complicated OB pt2.2

Question 1

At what platelet count do we completely forget about neuraxial anesthetic techniques?

Answer 1

< 50,000/ mm³ ⇒ GETA

Question 2

At what platelet count are we good to go on utilizing neuraxial techniques?

Answer 2

> 80,000 mm³

50-80k = weigh benefits/risks

Question 3

What is the defining characteristic of eclampsia vs preeclampsia?

Answer 3

Eclampsia:

• New onset seizures
• Unexplained coma
• In conjunction with previous s/s of preeclampsia

Question 4

When is the most common onset of eclampsia?

Answer 4

Intrapartum or 48 hours postpartum

late eclampsia: 48hrs up to 4 weeks

Question 5

What are the possible complications of Eclampsia?

Answer 5

Question 6

What mechanism is lost in eclampsia?

Answer 6

Cerebral autoregulatory mechanism

Question 7

What is the resulting issue behind the loss of the cerebral autoregulatory mechanism?

Answer 7

Hyperperfusion → interstitial or vasogenic cerebral edema → ↓ CBF

may possibly manifest Posterior Reversible Encephalopathy Syndrome (PRES)

Question 8

What may be seen on a FHT strip during or after an eclamptic seizure episode?

Answer 8

Fetal bradycardia

NOT requirement for immediate delivery unless prolonged

Question 9

What is the treatment for eclamptic seizures?

Answer 9

Stop seizures:

• Magnesium (consider infusion as well to prevent recurrent sz)
• Consider midazolam/diazepam/lorazepam

maintain patent airway and prevent hypoxia or aspiration

Question 10

When is neuraxial anesthesia acceptable for eclamptic parturients?

Answer 10

If patient is conscious w/ no recent seizures

Question 11

If an eclamptic parturient has ongoing seizures what kind of anesthetic is necessary?

Answer 11

GETA w/ propofol = ↓ CMRO₂ & CBF = ↓ ICP

Question 12

Why should hypoventilation be avoided in eclamptic patients?

Answer 12

Hypoventilation = ↓ seizure threshold

Question 13

What are the three H’s that should be avoided to minimize neurologic injury to eclamptic parturients?

Answer 13

• Hypoxemia
• Hyperthermia
• Hyperglycemia

Question 14

What is the presentation of Amniotic Fluid Embolism (AFE)?

Answer 14

Classic Triad

• Hypoxia (Phase 1)
• Hypotension (Phase 2)
• Coagulopathy (Phase 3)

Question 15

What is the fetal presentation of amniotic fluid embolism?

Answer 15

• O₂ shunted from uterus to mom
• Decels/bradycardia
• Loss of variability

Question 16

What is the anesthesia management of amniotic fluid embolism?

Answer 16

A-OK

• Atropine: for vagolysis
• Ondansetron for vagolysis
• Ketorolac blocks thromboxane production

Question 17

What condition is treated utilizing misoprostol (cytotec)?

Answer 17

Post-partum hemorrhage

Question 18

What are the four drugs utilized for uterine atony? (in order of what should be tried first, assuming the patient has no medical hx).

Answer 18

1. Oxytocin (pitocin)
2. Methylergonovine (methergine)
3. Carboprost (Hemabate)
4. Misoprostol (cytotec)

Question 19

If able to use it, what are the primary benefits of neuraxial anesthesia in preeclampsia parturients?

Answer 19

• management of HTN
• avoidance of airway management in difficult airway

CLE and CSE preferred methods for labor analgesia

Question 20

When utilizing neuraxial anesthesia with a preeclampsia, what should be considered regarding the use of additives to your local anesthetic dose?

Answer 20

Use of epinephrine containing local anesthetics can potentially cause worsened HTN

Question 21

What is the typical platelet count where the provider would be comfortable with epidural catheter removal?

Answer 21

Platelet count > 75 - 80k/mm³

recheck platelets before pulling in these patients

Question 22

In preeclampsia, IV hydration should be used cautiously bc of risk of pulmonary edema. A narrow pulse pressure would cause the provider to consider what?

Answer 22

Consider preload in narrow pulse pressure

Question 23

In preeclampsia, vasopressors are preferred to manage HoTN. What should be considered regarding pressor administration in these patients?

Answer 23

• Potential increased sensitivity to vasopressors
• Use a smaller dose of pressor admin

25-50mcg Neo, 5-10mg Ephedrine

Question 24

Why would a preeclampsia parturient potentially have a falsely negative test dose of epi in local anesthetic?

Answer 24

These patients may have been treated with a longer acting beta blocker such as Labetalol, this can mask the tachycardic response from a positive test dose

Question 25

Why is tracheal intubation a particular concern in preeclamptic parturients? What should be done to mitigate this risk?

Answer 25

* Risk of severe, exacerbated HTN with tracheal intubation & emergence/extubation * Should blunt the sympathetic response during these times * Fentanyl may be avoided d/t effects on the fetus, so may use something short acting such as Esmolol

Question 26

During GETA induction of a preeclamptic parturient, what are blood pressure goals before induction? What should it be maintained at?

Answer 26

* Reduce to ~140/90 before induction * Maintain sBP 140 - 160 mmHg * Maintain dBP 90 - 100 mmHg

Question 27

Why might labetalol not be a great choice for blunting sympathetic response with induction? What might be a better option, and what dose?

Answer 27

* Labetalol is longer-acting and may drop your blood pressure too much post-induction * Esmolol 2mg/kg may be a better option *Remifentanil 0.5mcg/kg also a decent option because it goes away quickly (unlike fentanyl)*

Question 28

When does preeclampsia typically resolve? What significant feature can be seen with this resolution and why?

Answer 28

* Preeclampsia usually resolves within 5 days postpartum * Marked diuresis may be noted from ECF shifts back intravascularly *risk of pulmonary edema is greatest at this time*

Question 29

With preeclampsia, risk of what is highest in the postpartum period? What should be done to mitigate this risk?

Answer 29

* Risk for CVA highest postpartum * Antihypertensive treatment for sBP>150 or dBP>100 * Continue magnesium sulfate for 24 hours

Question 30

What is the most common premonitory neuro symptom for eclampsia?

Answer 30

* headache and visual disturbances

Question 31

In eclampsia, what might be seen prior to a tonic phase of seizures?

Answer 31

Facial twitching *tonic phase may be followed by clonic phase, apnea, and postictal state*

Question 32

What anesthetic management considerations should be made when managing an eclamptic parturient?

Answer 32

* Avoid increases in intracranial pressure * Restrict fluids to decrease risk of exacerbated cerebral edema * Similar management to a severe preeclamptic parturient

Question 33

Why is hyperventilation generally not indicated in an eclamptic parturient?

Answer 33

Hyperventilation decreases CBF but does not decrease CMRO₂

Question 34

What is the mechanism of action of an Amniotic Fluid Embolism (AFE)?

Answer 34

* anaphylactoid syndrome of pregnancy causing systemic inflammatory response from release of endogenous proinflammatory mediators * Does not create a "mechanical blockade" to pulmonary circulation like previously assumed

Question 35

What characterizes Phase 1 of an Amniotic Fluid Embolism (AFE)?

Answer 35

* Acute pulmonary HTN ⇒ Right Ventricular failure and dilation ⇒ decreased CO, VQ mismatch ⇒ Hypoxia

Question 36

What characterizes Phase 2 of an Amniotic Fluid Embolism (AFE)?

Answer 36

* RV function improves but LV failure predominates ⇒ decreased CO, pulmonary edema, cardiac arrest *occurs 15-30 min after initial event*

Question 37

What characterizes Phase 3 of an Amniotic Fluid Embolism (AFE)?

Answer 37

* coagulopathy: Tissue factor and factor VII activate extrinsic pathway of clotting cascade ⇒ consumptive coagulopathy develops ⇒ Hemorrhage and DIC

Question 38

What medications should be considered when managing Phase 1 of AFE?

Answer 38

Consider Dobutamine and Milrinone to improve Right Ventricular output *Norepi or vasopressin for HoTN management*

Question 39

What should be considered in managing Phase 2 of AFE?

Answer 39

* Avoid excess fluid administration that can further dilate the RV * Dobutamine and Milrinone to improve LV contractility

Question 40

What management should be done with Phase 3 of AFE?

Answer 40

* Activate MTP * Maintain PLT >50k and normal PTT/INR * Tranexamic Acid (TXA)

Question 41

Review this chart for the pathways of AFE:

Answer 41