Anesthesia for the Obstetric PatientUndergoing Non-Obstetric Surgery

Daniel Rohrer, CRNA, MS Pinnacle Health- Community General Osteopathic Hospital

Conflicts & Disclosures This presentation lacks any conflict of interest or commercial interest for disclosure

Objectives • Briefly review the physiologic changes in the

obstetric patient and their implications for anesthetic management

• Review common non-obstetric surgical procedures, techniques, and concerns surrounding fetal vulnerability

• Outline the anesthetic guidelines in managing the obstetric patient throughout non-obstetric surgery

Airway, Breathing…

VE/VO2

VE/VCO2

Airway, Breathing…

Cardiovascular & Circulation…

Cardiovascular & Circulation…

Gastrointestinal…

• Increased gastric volume

• Mechanical outflow obstruction

• Delayed gastric emptying

• Increased gastric pressure

• Decreased motility and esophageal sphincter tone

Other Changes…

Other Changes…

Non-Obstetric Surgery0.75-2% 1:500-635 75,000 per year

Appendicitis & Cholecystitis

You can do that?...

(Appendectomy)

Quick breather…

• Protection of Fetus

• Pre-Term Labor

• Principles & Guidelines

Fetal Vulnerability & Teratogenicity (Protection)

Timing

Physical & Chemical Properties• Size : < 500 Da (Daltons) • Charge: Non-ionized • Protein Binding: Unbound drugs • Lipophilic

Placental Drug Transfer (Protection)

Teratogenicity (Protection)

• Susceptibility • Dose • Duration • Timing of exposure

Important Factors: FDA categories: •A - known to be safe •B - appear to be safe •C - may cause problems •D - clear risks •X – confirmed defects

Teratogenicity (Protection)

“To the best of our knowledge, danger of teratogenic effects from currently available anesthetic or sedative drugs remains only

a potential risk” Dr. Rosen-ASA

Pre-Term Labor & Delivery

To use or not to use…?

Respiratory and Hemodynamic Stability (Principles)

28-32 mmHg

Uterine Blood Flow & Fetal Asphyxia

• Left uterine displacement

• Trendelenburg position

• Fluid administration as indicated

• Leg elevation

• Vasopressors (ephedrine & phenylephrine)

• Minimal SBP = 100mmHg

• Hypotension = < 2 minutes

Fetal Heart Monitoring(ACOG & ASA)

• Individualized

• Minimum before and after

• Obstetric consultation & interpretation

• Institution with neonatal services

• Consent for emergent C-section

• Physician with C-section privileges

Carefully…Consent…

Carefully…Consent…

Paravertrebral Block: An Option?

American College of Obstetricians and Gynecologists (ACOG)

• Cesarean section: 30 minutes • “Immediate” availability of personnel • Physician with anesthesia privileges • Resources for local anesthetic toxicity • Newborn resuscitation team

In Conclusion…• Physiological Changes • Protection of the fetus (timing, teratogenicity) • Pre-Term Labor prevention • Principles for maternal and fetal stability

…and anesthetists!!!

“Precision and circumspection must be had and utilized when dealing with general anesthesia and pregnancy”

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