1. Denise Weiss DO Anesthesiologist
OB Anesthesia
Denise Weiss DO
Anesthesiologist

2. Goals of obstetrics
Healthy mom/baby = happy and healthy doctors and nurses, family

3. OB Anesthesia NPO guidelines Solid food (fatty foods) = 8hrs
Light meal (toast, crackers, etc) = 6 hours
Clear liquids =2 hours
Breast milk = 4 hours
On L/D clear liquids ok during labor, (often only ice chips allowed)
Stricter adherence to ice chips if higher risk of operative delivery
Scheduled inductions should be instructed to be NPO
All pregnant pts are considered to have full stomachs but the goal is to minimize risk if need for intubation occurs

4. OB Anesthesia Reasons for NPO guidelines:
Higher risk of aspiration in pregnant patients (1 in 661 vs 1 in 2131 gen pop)
Increased intragastric pressure due to large uterus
LES is pushed up and to the left (sim to hiatal hernia)
Decreased LES tone secondary to progesterone
High incidence of GERD
Gastric pH is more acidic
Active phase of labor slows gastric emptying

5. OB Anesthesia Higher risk of difficulty in airway management
Morbidity/mortality in pregnant pts have been attributed often to failed or difficulty managing the airway
Airway is more friable and edematous in pregnant pts
Increased breast size can make laryngoscopy very difficult
Decreased FRC so desaturate quickly

6. OB Anesthesia
pH less than 2.5 and gastric volume greater than 25ml are identified risk factors for aspiration
Pregnant pts going to CS either emergently or scheduled receive pharmacologic prophylaxis (we use reglan and alka selzer gold, bicitra increases pH without altering volume)

7. OB Anesthesia Difficult airway
Incidence of failed intubation in obstetric
1:2330 in general OR population
Airway complications are the leading cause of anesthesia mortality
Single largest class of injury related claims from the ASA Closed Claims database involves respiratory events

8. OB Anesthesia Basic Needs for the OR Monitors
ECG,NIBP,SPO2, FHR monitor, suction
Equipment for difficult airway, and emergency drugs
Checked daily

9. OB Anesthesia for C-Section
Spinal
Epidural
Combined Spinal/epidural
General
Local

10. Contraindications for Neuraxial Techniques
Pt refusal or inability to cooperate
Increased ICP secondary to mass lesion
Skin or soft tissue infection at site of needle placement
Coagulopathy
Uncorrected maternal hypovolemia
Low platelets (depends)

11. Complications with Neuraxial Techniques
Infection
Postdural Puncture Headache
Incomplete or failed block
Neurologic injury(incidence is 20 in 1.2million for subarachnoid blocks, 20 in 450,000 for epidurals)
Meningitis or arachnoiditis
Spinal hematoma(sharp back and leg pain-numbness and motor dysfunction(loss of bowel/bladder fxn)
Emergent MRI or CT and referral (6-12 hr window for decompression)

12. Spinal and Epidural Anesthesia

13. Combined Spinal/Epidural

14. General Anesthesia
Maternal refusal or inability to cooperate with neuraxial tech
Presence of contraindication to neuraxial tech
Insufficient time to induce neuraxial tech(cord prolapse with persistent bradycardia)
Failure of neuraxial technique
Fetal issues (EXIT procedure)

15. Local Anesthesia Very rarely used
Dire emergencies when anesthesiologist/CRNA not available
Success dep on avoiding use of retractors, and not exteriorizing the uterus.
After delivery of baby, obtain hemostasis until arrival of anesthesia personnel

16. Local Anesthesia 0.5% lidocaine with epi
25g spinal needle to create skin wheal just below umbilicus directed toward symphysis pubis. SQ injection along this full area.
Ideally wait 3-4 min to take effect
Vertical incision to rectus then local into rectus fascia and muscles. Takes 4-5min for anesthesia to be complete

17. Local Anesthesia Parietal peritoneum infiltration and incision
Visceral peritoneum infiltration and incision
Paracervical injection
Uterine incision and delivery
Obtain hemostasis
Await availability of general anesthesia

18. Local Anesthesia Disadvantages Pt discomfort
Risk for local anesthetic toxicity (may use up to 100ml of local
Difficult operating conditions to say the least

19. Maximum Local Anesthetic Dosages
Easy formula for bupivicaine (for 0.25% can give 1cc/kg, for 0.5% can give 1/2cc per kg. Lidocaine 4cc/kg plain, 7cc/kg with epi (for obese pts keep in mind max dose)

20. PCA Fentanyl Great alternative for pts who cannot have an epidural
All opioids cross placenta by diffusion secondary to lipid solubility
All are associated with neonatal depression
Fentanyl readily crosses placenta but avg umbilical to maternal conc ratio is low at 0.31
Studies show reduced FHR variability but difference in APGAR scores, respiratory depression and Neurologic and Adaptive Capacity scores at 2-4 hrs or 24 hrs compared to infants whose mothers did not have fentanyl(Am Journal of Obst/Gyn; Anesth/Analgesia)

21. PCA Fentanyl Rapid onset High potency Short duration
No active metabolites
One of most commonly used for PCA

22. PCA Fentanyl Must have resuscitation equip available
Pulse oximetry, +/- etCO2 monitoring
One/one nursing
Education of family members
Loading dose (50-150mcg
Bolus 25-50mcg(start at 25, and assess)
Lockout 10min
No basal rate

23. PCA Fentanyl
As labor progresses may need to decrease lockout time to 5min

24. OB in Rural Areas
Likely will not have immediately available anesthesia provider
OB nurses can assist with management of epidural infusions
ASA has a consultation program that will help with setting up the anesthesia service to fit the needs of the facility
Consensus of all involved that OB anesthesia is a priority and a worthwhile goal

25. OB in Rural Areas
Anesthesia provider does NOT have to stay in house during course of epidural infusion
ASA recommends it but recognizes difficulty

26. Questions???