Mod VII: Anesthesia for Cesarean Section

Question 1

_{Anesthesia for Cesarean Section}

What’s the rate of Cesarean Section in the US?

Answer 1

Exceeds 30% in the U.S.

Question 2

_{Anesthesia for Cesarean Section}

Reasons for Cesarean Section are variable and include:

Answer 2

Repeat C/S (classical)

Malpresentation

^{(Breech presentation)}

Placental abnormalities

^{(<strong>Placenta abruptio</strong> where the placenta is separating from the uterine wall - <strong>Placenta previa</strong> where part of the placenta is in the birth canal)}

Transverse position

Fetal distress

Maternal distress

Question 3

_{Anesthesia for Cesarean Section}

What’s the classical reason for having a C-section?

Answer 3

Repeat C/S

This is because any scaring in the uterus is a potential weak spot for possible uterus rupture

This is a serious concern if subsequent vaginal delivery is attempted after C/S

VBAC: Vaginal Birth After C-section

Be familiar with this

Many obstetrician don’t like them

VBACs are a/w a higher incidence of emergency C-sections

Question 4

_{Anesthesia for Cesarean Section}

Comorbidities a/w Cesarean Section include:

Answer 4

Obesity - Diabetes - HTN

^{(Chronic - PIH - Preeclampsia)}

Cardiac abnormalities

Question 5

_{Anesthesia for Cesarean Section}

Picture showing a pt being prepped for c-section

Answer 5

Picture showing a pt being prepped for c-section

Question 6

_{Anesthesia for Cesarean Section}

Types of incisions seen with C-section

Answer 6

Horizontal incision

^{(also known as the Fenestone incison is the most common)}

Vertical incision

Question 7

_{Anesthesia for Cesarean Section}

Graphical representation of C-section after incision has been made and the uterus is accessed

Answer 7

Graphical representation of C-section after incision has been made and the uterus is accessed

The physician will insert fingers inside and pull appart the uterus and then deliver the fetus

Question 8

_{Anesthesia for Cesarean Section}

Picture showing pressure being applied to upper part of the uterus to deliver fetus

Answer 8

MD will usually place a large amount of pressure on the upper part of the uterus to deliver the fetus via the uterine incision

Be prepared; this can be really uncomfortable for the mother

Question 9

_{Anesthesia for Cesarean Section}

Picture showing clamping and cutting of the umbilical cord after delivery

Answer 9

Picture showing clamping and cutting of the umbilical cord after delivery

Following this, the infant/neonate is passed on to a different team that will care for the infant/neonate as a separate pt

Question 10

_{Cesarean Section (C-S) and Anesthesia}

What are anesthetic options for c/s

Answer 10

Use epidural if already in place

^{(appropriate for pts who attempted a vaginal birth and had a failure to progress, or became destressed)}

Use of spinal anesthesia

^{(placed while the pt is still on the table and right before they lay down to have the c/s)}

General Anesthesia

Question 11

_{Cesarean Section (C-S) and Anesthesia}

Anesthesia alone is the cause of 3-12 % maternal deaths -This is usually due to:

Answer 11

Failed intubation

Failed ventilation and oxygenation

Aspiration

Question 12

_{Cesarean Section (C-S) and Anesthesia}

What is the best type of anesthesia for C-Section in light of the above?

Answer 12

Anything that avoids the pt’s airway

Avoid General anesthesia at all costs!!!

Question 13

_{Cesarean Section (C-S) and Anesthesia}

What’s probably the most popular and most commonly used type of anesthesia for Cesarean Section?

Answer 13

Spinal Anesthesia for C-S

Question 14

_{Cesarean Section (C-S) and Anesthesia}

What are the Pros of Spinal Anesthesia for C-S?

Answer 14

Technical ease of administration (vs epidural or GA)

Rapid, dense anesthesia block

Low fetal exposure

Maternal alertness

Presence of coparent

Question 15

_{Cesarean Section (C-S) and Anesthesia}

What are the Cons of Spinal Anesthesia for C-S?

Answer 15

Hypotension

Prolonged recovery time

Limited usefulness in emergencies

^{(b/c no time to place the pt in spinal position - in which case you would use existing epidural if available or will just move to a GA)}

Question 16

_{Cesarean Section (C-S) and Anesthesia}

T/F: Monitors are required during Spinal Anesthesia for C-S

Answer 16

True

Question 17

_{Spinal Anesthesia for C-S}

Premedication for Spinal Anesthesia for C-S includes:

Answer 17

Anxiety – usually verbal only

Hypotension prophylaxis

Bacitra

Metoclopramide-if nausea or recent food ingestion

Question 18

_{Spinal Anesthesia for C-S}

Fluids management considerations for Spinal Anesthesia for C-S includes:

Answer 18

Administer Crystalloid vs. Colloid

Be aware of HTN, hypovolemic, preeclamptic

Question 19

_{Spinal Anesthesia for C-S}

A what level is Spinal Anesthesia for C-S placed?

Answer 19

T4

Question 20

_{Spinal Anesthesia for C-S}

Which drug combinations and dosings are used for Spinal Anesthesia for C-S?

Answer 20

Lidocaine 60-75 mg = 45-75 minutes

Epinephrine 100-200 mcg (to increase block duration)

Choice of a Narcotic

10-25 mcg fentanyl, or

5-10 mcg sufentanil, or

100-250 mcg morphine (Duramorph)

Question 21

_{Spinal Anesthesia for C-S}

Wha’s the most common drug combination and dosing used for Spinal Anesthesia for C-S?

Answer 21

Lidocaine 60-75 mg = 45-75 minutes

Epinephrine 100-200 mcg (to increase block duration)

10-25 mcg fentanyl

Question 22

_{Spinal Anesthesia for C-S}

Bupivacaine is the most favored LA for spinal Anesthesia for C-S - How is it administered?

Answer 22

Bupivacaine: 7.5-15 mg => 60-120 mins of analgesia

+ Choice of Narcotic

Fentanyl 10-25 mcg, or

Sufentanil 5-10 mcg

Question 23

_{Spinal Anesthesia for C-S}

You are to administer 12 mg of Of 0.75% bupivacaine + 20 mcg fentanyl+/- duramorph 0.1 - 0.2 mg. How many cc of drugs will you administer?

Answer 23

1.) Determine how many mg of bupivacaine are in 0.75% bupivacaine, vs. 0.25%, vs 0.5%

^{0.75% bupivacaine = 7.5mg/mL}

^{0.25% bupivacaine = 2.5mg/mL}

^{0.5% bupivacaine = 5.0mg/mL}

2.) How many cc are in 20 mcg fentanyl

^{Fentanyl 50 mcg/mL}

3.) How many cc are in 0.1-0.2 mg od duramorph

_{Duramorph is available in 0.5mg/mL and 1mg/mL}

_{Possible math problems on the exam}

Question 24

_{Spinal Anesthesia for C-S}

After dosing Spinal Anesthesia for C-S, what next?

Answer 24

Return pt supine with slight LUD (Left Uterine Displacement)

Question 25

_{Spinal Anesthesia for C-S} What are Symptoms of High level effects of Spinal Anesthesia for C-S on breathing that you must be aware of after placing your spinal?

Answer 25

Decreased intercostals movement Thoracic proprioception ^{(they feel like they are not breathing even when they are; which is uncomforatble)} Cephalad displacement of abdomen ^{(esp. in the supine position)} Fundal pressure by surgeons

Question 26

_{Spinal Anesthesia for C-S} What are potential compliations of Spinal anesthesia?

Answer 26

**Hypotension** ^{Tx w/ Ephedrine - Phenylephrine} **High spinal** ^{Tx w/ Prompt intervention, resuscitation, ABCs} **Failed spinal, patchy block** ^{Tx: Redo spinal (if time allows) Tx: Supplement with nitrous or ketamine boluses Tx: Convert to a GA (worst case scenario)}

Question 27

_{Spinal Anesthesia for C-S} Which drugs are used to treat Hypotension resulting from spinal anesthesia?

Answer 27

**Ephedrine - Phenylephrine**

Question 28

_{Spinal Anesthesia for C-S} How is "High spinal" resulting from spinal anesthesia treated?

Answer 28

Prompt intervention Resuscitation ABCs

Question 29

_{Spinal Anesthesia for C-S} How is Failed spinal or patchy block resulting from spinal anesthesia treated?

Answer 29

Redo spinal (if time allows) Supplement with nitrous or ketamine boluses Convert to a GA (worst case scenario)

Question 30

_{Epidural Anesthesia for C-S} What are advantages of using Epidural Anesthesia over spinal anesthesia for C-S? _{Epidural Anesthesia for C-S}

Answer 30

Could use incremental dosing Extension from labor period ^{(no need looking for another access)} Less intense motor blockade ^{(Less likely to impair ventilation (pulmonary, twins)} Less occurrence of PDPH

Question 31

_{Epidural Anesthesia for C-S} Which provides a more intense motor blockade? A. Spinal B. Epidural

Answer 31

**A. Spinal** B. Epidural

Question 32

_{Epidural Anesthesia for C-S} Which is associated with Less occurrence of PDPH? A. Spinal B. Epidural

Answer 32

A. Spinal ## Footnote **B. Epidural**

Question 33

_{Epidural Anesthesia for C-S} What are disadvantages of Epidural Anesthesia for C-S?

Answer 33

**Not as dense as spinal** _Not suitable for emergencies_ ^{(use it if already inplace in case of emergency - If none in place, it takes more skill and time to place an epidural than it takes to place a spinal)} **Dural puncture with medication delivery,** which could require ^{Intubation - PPV - Maternal resuscitation, fluids, vasopressors - Prompt delivery if necessary}

Question 34

_{Epidural Anesthesia for C-S} Patient preparation for placement Epidural Anesthesia for C-S includes:

Answer 34

**Monitors** **Fluids** 15-20 ml/kg **Bicitra** 30 ml

Question 35

_{Epidural Anesthesia for C-S} Pt should be returned to which position after Epidural placement?

Answer 35

Supine with LUD

Question 36

_{Epidural Anesthesia for C-S} Which drug combinations and dosing are commonly used for Epidural Anesthesia for C-S?

Answer 36

**_2% Lidocaine with epi_** Epi 5 mcg/ml Epi Decrease absorption LA ^{(by constricting the arteries and reducing the amount of LA that's washed away} Epi Increase intensity of block **_2 or 3% Chloroprocaine_** Very rapid onset 40-50 min duration ^{Sometimes will cover a patchy block (Appropriate if the pt they can still "feel" something!!!)}

Question 37

_{Epidural Anesthesia for C-S} T/F: Complications of Epidural Anesthesia for C-S are Similar to spinal

Answer 37

**True**

Question 38

_{Combined Spinal-Epidural Anesthesia for C-S} Why is the combined Spinal & Epidural Anesthesia for C-S becoming increasingly popular?

Answer 38

Advantages of spinal with epidural back up This means that you could start w/ a spinal but runout of time Your only option then will be to convert to a GA You could avoid GA if you have an epidural in place In which case you would just dose through the epidural

Question 39

_{Combined Spinal-Epidural Anesthesia for C-S} Which technique is used for the combined Spinal-Epidural Anesthesia for C-S?

Answer 39

**Needle-through-needle** Tuohy needle + spinal needle inside Tuohy needle (1) You would inject the medication into the subarachnoid space (2) Then you would tread the epidural catheter in the epidural space Requires _Longer spinal needle, special kits_

Question 40

_{General Anesthesia for C-S} When is General Anesthesia indicated for C-S?

Answer 40

Fetal distress Maternal emergency Acute hypovolemia Significant coagulopathy ^{(preventing from doing a neuraxial technique)} Inadequate regional anesthesia ^{(the block is just too patchy and the pt cannot tolerate the pain)} Maternal refusal of regional anesthesia\* **You want to avoid a GA in an obstetric pt if at all possible!!!**

Question 41

_{General Anesthesia for C-S} The biggest disadvantage of General Anesthesia for C-S is Difficult airway - How should you prepare for it?

Answer 41

Careful exam Difficult airway cart ^{(have LMAs and intubating adjuncts available)} Awake fiberoptic Stubby intubating handles ^{(make sure they are not on the way as you try to intubate the pt)} **_{Refer to Box 77-3 and Figure 77-4 in Miller’s Anesthesia}**

Question 42

_{General Anesthesia for C-S} What's the Suggested Sequence for General Anesthesia for Cesarean Section?

Answer 42

1. Administer a nonparticulate oral antacid (**sodium citrate**) before induction of anesthesia with consideration for _metoclopramide_ or a _histamine-2 blocker_ 2. Place standard **monitors**, _maintain left uterine displacement_, and ensure suction, airway equipment, and appropriate drugs are readily available. 3. Ensure the patient has a working **intravenous catheter** and start an infusion of _crystalloid solution_. 4. If time permits (nonemergent), administer prophylactic **antibiotics** and participate in _time-out_ checklist. 5. **Preoxygenate/denitrogenate** patient for more than 3 minutes or 4 maximal (vital capacity) breaths over 30 seconds with 100% oxygen. 6. When the _surgeon is ready_ and patient prepared, an assistant should apply **cricoid pressure** (and maintain until the position of the endotracheal tube is verified).\* 7. Notify and confirm with the surgeon that the patient is ready for induction of anesthesia. 8. Administer **induction agent** and **muscle relaxant** in rapid sequence, wait 30 to 60 seconds, and then initiate _direct laryngoscopy_ for tracheal intubation. Consider using _etomidate_ or _ketamine_ if concern for hypotension exists. 9. After confirming endotracheal tube placement, communicate to surgeon to proceed with incision. 10. Administer **50% nitrous oxide in oxygen** with **0.5 to 0.75** minimum alveolar concentration (MAC) of a halogenated anesthetic. 11. Adjust minute ventilation to maintain normocarbia (end-tidal carbon dioxide 30 to 32 mm Hg). 12. After delivery, anesthesia may be augmented by administering opioids, barbiturates, or propofol while continuing the volatile anesthetic. Additional muscle relaxant may be considered if necessary. 13. Administer **_oxytocin_** and assess uterine tone. 14. **Extubate** the trachea when the patient is _awake_ and following commands and neuromuscular blockade is fully reversed.

Question 43

_{General Anesthesia for C-S} How would you address Aspiration risk a/w General Anesthesia for C-S?

Answer 43

Prophylactic pharmacologic intervention RSI

Question 44

_{General Anesthesia for C-S} How would you address Placental transfer of drugs a/w General Anesthesia for C-S?

Answer 44

Ensure surgeon limits **Uterus-Drug (U-D) time** \< 3 minutes (Do not induce until the surgeon is ready to cut - From the time you induce, the surgeon must try to get a clamp on the umbilical cord w/in 3 minutes)

Question 45

_{General Anesthesia for C-S} What are some psychosocial disadvantages of General Anesthesia for C-S?

Answer 45

Decreased maternal-fetal bonding ^{(mother asleep)} Absence of coparent ^{(not allowed in the room during GA)}

Question 46

_{General Anesthesia for C-S} What does a typical General Anesthesia Plan for C-S include?

Answer 46

Clear antacid, H2 antagonist, metoclopramide LUD Monitors Denitrogenation Cricoid Pressure Propofol, succinylcholine Intubation\* ^{(use smaller than calculated tube size b/c tracheal edema)} Confirm breath sounds Tell the surgeon to cut Run the case w/ 0.5 MAC of volatile agent with 30- 50% nitrous Muscle relaxation ^{(must take into consideration if the pt has been of MgSO4 which accentuates the effects of muscle relaxants)}

Question 47

_{General Anesthesia for C-S} Which drug is administered once the fetus has been delivered? what should you watch for during administration of this drug?

Answer 47

_Oxytocin_ 20 U in 1000 cc LR, wide open Watch for **hypotension**

Question 48

_{General Anesthesia for C-S} Which drugs are administered post delivery for anxyolysis and analgesia?

Answer 48

**_Versed_** 2 mg _Fentanyl_ 1-2 mcg/kg _Morphine_ 0.1 mg/kg

Question 49

_{General Anesthesia for C-S} What are required reversals and other precautions prior to extubation following General Anesthesia for C-S?

Answer 49

NMB reversal Thorough suction Extubation when airway reflexes intact

Question 50

_{General Anesthesia for C-S} A uterus that is still spongy feely after the fetus and placenta have delivered is dubbed:

Answer 50

**"Boggy uterus"**

Question 51

_{General Anesthesia for C-S} Intrauterine administration of which drugs would you anticpipate if "Boggy uterus" is present?

Answer 51

OB surgeon may want **Pitocin** for intrauterine injection Methylergonovine 0.2 mg IM (IV rare) (**Methergine**) Carboprost tromethamine (**Hemabate**)

Question 52

_{Effects of Anesthesia on Fetus and Neonate} How can we prevent _fetal hypoxemia_ and **acidosis** that are often d/t anesthesia?

Answer 52

LUD Ensure adequate maternal oxygenation Avoid maternal hyperventilation Avoid excessive dose of anesthetic agents Treat hypotension promptly U-D interval of less than 3 minutes is optimal