Updates in Obstetric Anesthesia

Educational Objectives

The goal of this program is to improve patient care in obstetric anesthesia. After hearing and assimilating this program, the clinician will be better able to:

1. Optimize pain control through use of obstetric analgesia.
2. Minimize risks and adverse effects associated with use of obstetric analgesia.

Summary

Labor epidural analgesia (LEA)

Benefits: Guglielminotti (2022) reported a 14% reduction in maternal morbidity with LEA; Guglielminotti et al (2023) demonstrated decreased risks for peripartum hemorrhage and maternal blood transfusion during vaginal delivery or intrapartum cesarean delivery (CD); blood transfusions decreased by ≤45%; Meng et al (2023) demonstrated reductions in third- or fourth-degree perineal lacerations, maternal requests for CD, and 5-min Apgar scores ≤3 with receipt of LEA

Bolus vs infusion: programmed intermittent epidural bolus (PIEB) is superior to continuous background infusion with regard to sensory dermatome coverage; high-dose patient-controlled epidural analgesia may be an alternative to PIEB if a programmed pump is unavailable; optimal bolus dosing — Ran et al (2022) reported an average bolus volume of 7 to 11 mL with an interval of ≈45 min

Dural puncture epidural (DPE) technique: has faster onset, delays time to the first epidural “top-up” dose, and offers better sacral coverage, compared with standard epidural technique; compared with standard epidural technique, DPE does not reduce incidence of headache or need for blood patch

Adjuvants for LEA: some clinicians use dexmedetomidine for epidural and spinal analgesia, though no official consensus exists; dexmedetomidine imparts a lower risk for pruritus but causes maternal bradycardia; dexmedetomidine is a good alternative to fentanyl when avoiding intrathecal narcotics; the American Society of Anesthesiologists (ASA) published a guide for alternative drugs to use when standard drugs are unavailable; use clinical judgment, as some drugs are not approved by the US Food and Drug Administration

LEA and autism spectrum disorders (ASDs): Qiu et al (2020) demonstrated an association between LEA and offspring development of ASDs; after accounting for confounders, Hegvik et al (2023) demonstrated no direct link between LEA and ASD or attention-deficit/hyperactivity disorder; evidence was recently substantiated regarding lack of a link between offspring development of ASD and maternal receipt of LEA

Cesarean delivery (CD)

Options for analgesia: scheduled medications (eg, acetaminophen, nonsteroidal anti-inflammatory drugs) enhance postsurgical analgesia and can also be administered before CD; neuraxial morphine requires monitoring for several hours but provides good analgesia; intravenous dexamethasone seems to impart an opioid-sparing effect; transversus abdominis plane (TAP) and quadratus lumborum blockade are also used, especially in the absence of spinal or neuraxial analgesia; avoid gabapentin, as it causes sleepiness and has not shown significant benefit; lidocaine patches are effective for postsurgical pain; pain during CD — poorly functioning epidurals result in patient discomfort and challenging surgery; ensure functional neuraxial blockade before starting CD; use supplemental analgesics and adjuvants as part of intrapartum management; convert to general anesthesia (GA) if required; follow-up with patients who report pain during CD, and provide resources for support

Adverse effects after CD: pruritus is most common; antihistamines do not work; serotonin antagonists administered before neuraxial blockade may mitigate pruritus; subhypnotic doses of propofol (10-20 mg) are also effective; thrombocytopenia (platelet count <70,000/mL) — per the ASA and the Society for Obstetric Anesthesia and Perinatology consensus statement (Bauer et al [2021]), the risks for epidural or spinal hematoma are very low with platelet count ≥70,000/mL; patients with gestational hypertension may have thrombocytopenia; one study demonstrated that patients with immune thrombocytopenic purpura and gestational thrombocytopenia seem to be more stable than those with severe preeclampsia; Seymour et al (2023) found that 90% of patients could have avoided GA (and received neuraxial blockade) had a platelet count been available; “single-shot” spinal anesthesia is an option for patients in this situation

Use of chloroprocaine: Lee et al (2023) reported no difference in postoperative pain control between epidurals using 3% chloroprocaine and 2% lidocaine; consider long-acting anesthetics to bridge the gap between chloroprocaine wearing off and neuraxial morphine taking effect

Anesthetic complications: postdural puncture headaches — conservative management (ie, oral or intravenous fluids) is underused; complete bedrest with the patient lying flat is ineffective; schedule acetaminophen and nonsteroidal anti-inflammatory drugs; recent evidence suggests that an epidural blood patch (EBP) should be placed ≈48 hr after dural puncture; conservative treatment is recommended before then; more rapid onset of headache is associated with more rapid onset of cerebrospinal fluid leak and intracranial hypotension; proceed with earlier EBP in patients with evidence of cranial nerve palsy, dizziness, or diplopia; nontreatment may induce depression or chronic headaches; no evidence exists to support use of cosyntropin; epidural hematoma or abscess — urgently obtain neuroimaging (magnetic resonance imaging [MRI] is preferred, though obtain computed tomography if MRI is unavailable) and escalate to neurosurgery

Maternal mortality (Simpson [2023]): increased in 2021 to 33 per 100,000 births, then returned to prepandemic levels (19 per 100,000 births) in 2023; death rate among Black mothers is 2.6-fold greater than among White or Hispanic mothers; age >40 yr is a risk factor; leading causes for maternal mortality include hemorrhage, hypertension, and embolism

General anesthesia for CD: evidence supports use of neuraxial analgesia over general anesthesia; the European literature has started evaluating elective CD in patients at low risk for aspiration and assessed elective use of laryngeal mask airway (LMA); it is important to consider the type of LMA to be placed, as the ventilation port has to be sufficiently large to accommodate an endotracheal tube (ETT; intubating LMAs and newer LMAs have too-small ventilation ports); a 6.0-mm diameter ETT might pass, but it is short, so a laryngeal mask tube is needed; an entry catheter is needed when direct (blind) intubation is not possible

Medical complications and comorbidities in pregnancy: the most common complications include hemorrhage, cardiac conditions, thromboembolism, and cardiomyopathy; mental health conditions are now considered the leading cause of maternal mortality, especially among White and Hispanic women; addiction may also increase mortality associated with mental health; 53% of deaths occurred ≤1 yr postpartum; postpartum hemorrhage (PPH) — prophylactic tranexamic acid is part of the treatment protocol; early notification of the labor and delivery anesthesia team improves outcomes; placenta accreta spectrum disorder — becoming more common because of the increased rate of CD; have a high index of suspicion in patients with previous CD, placenta previa, or dilation and curettage; mechanical adjuncts include resuscitative endovascular balloon occlusion of the aorta and intrauterine suction (shown to improve uterine atony in ≈90% of patients); employ devices early when medical interventions are ineffective; maternal sepsis — a leading cause of maternal mortality; healthy pregnant women compensate for its effects; baseline tachycardia may hinder diagnosis

Anesthesia and the fetus: no anesthetic agents are truly harmful; pregnancy (or refusal of testing) may lead to surgery cancellation, interfering with patient autonomy and associated with financial, social, and medical consequences

Sugammadex: avoid sugammadex during early pregnancy, as sugammadex encapsulates progesterone; inform women undergoing anesthesia that sugammadex may interfere with contraception; some evidence suggests initial use of sugammadex in GA may interfere with breastfeeding initiation, though does not interfere with women already breastfeeding

Readings

Bauer ME, Arendt K, Beilin Y, et al. The Society for Obstetric Anesthesia and Perinatology interdisciplinary consensus statement on neuraxial procedures in obstetric patients with thrombocytopenia. Anesth Analg. 2021;132(6):1531-1544. doi:10.1213/ANE.0000000000005355; Felder L, Saccone G, Scuotto S, et al. Perioperative gabapentin and post cesarean pain control: a systematic review and meta-analysis of randomized controlled trials. Eur J Obstet Gynecol Reprod Biol. 2019;233:98-106. doi:10.1016/j.ejogrb.2018.11.026; Guglielminotti J, Landau R, Daw J, et al. Use of labor neuraxial analgesia for vaginal delivery and severe maternal morbidity. JAMA Netw Open. 2022;5(2):e220137. doi:10.1001/jamanetworkopen.2022.0137; Guglielminotti J, Landau R, Daw J, et al. Association of labor neuraxial analgesia with maternal blood transfusion. Anesthesiology. 2023;139(6):734-745. doi:10.1097/ALN.0000000000004743; Hegvik TA, Klungsøyr K, Kuja-Halkola R, et al. Labor epidural analgesia and subsequent risk of offspring autism spectrum disorder and attention-deficit/hyperactivity disorder: a cross-national cohort study of 4.5 million individuals and their siblings. Am J Obstet Gynecol. 2023;228(2):233.e1-233.e12. doi:10.1016/j.ajog.2022.08.016; Lee LO, Ramirez-Chapman AL, White DL, et al. Postcesarean analgesia with epidural morphine after epidural 2-chloroprocaine: a randomized noninferiority trial. Anesth Analg. 2023;136(1):86-93. doi:10.1213/ANE.0000000000006109; Meng X, Ye J, Qiao P, et al. Labor neuraxial analgesia and its association with perinatal outcomes in China in 2015-2016: a propensity score-matched analysis. Anesth Analg. 2023;137(5):1047-1055. doi:10.1213/ANE.0000000000006435; Passi NN, Mutebi M, Tan M, Oliver CM. Contraceptive failure and sugammadex administration: a single centre survey and audit of professional knowledge and practice. Br J Anaesth. 2023;130(3):e412-e414. doi:10.1016/j.bja.2022.11.017; Qiu C, Lin JC, Shi JM, et al. Association between epidural analgesia during labor and risk of autism spectrum disorders in offspring. JAMA Pediatr. 2020;174(12):1168-1175. doi:10.1001/jamapediatrics.2020.3231; Simpson KR. Effect of the COVID-19 pandemic on maternal health in the United States. MCN Am J Matern Child Nurs. 2023;48(2):61. doi:10.1097/NMC.0000000000000895; Uppal V, Russell R, Sondekoppam R, et al. Consensus practice guidelines on postdural puncture headache from a multisociety, international working group: a summary report. JAMA Netw Open. 2023;6(8):e2325387. doi:10.1001/jamanetworkopen.2023.25387.

Disclosures

For this program, members of the faculty and planning committee reported nothing relevant to disclose.

Acknowledgements

Dr. Murugan was recorded at the Texas Society of Anesthesiologists 2024 Annual Meeting, held September 6-8, 2024, in San Antonio, TX, and presented by the Texas Society of Anesthesiologists. For information on future CME activities from this presenter, please visit https://tsa.org/. Audio Digest thanks the speakers and presenters for their cooperation in the production of this program.

CME/CE INFO

Accreditation:

The Audio- Digest Foundation is accredited by the Accreditation Council for Continuing Medical Education to provide continuing medical education for physicians.

The Audio- Digest Foundation designates this enduring material for a maximum of 1.00 AMA PRA Category 1 Credits™. Physicians should claim only the credit commensurate with the extent of their participation in the activity.

Audio Digest Foundation is accredited as a provider of continuing nursing education by the American Nurses Credentialing Center's (ANCC's) Commission on Accreditation. Audio Digest Foundation designates this activity for 1.00 CE contact hours.

Lecture ID:

AN664402

Expiration:

This CME course qualifies for AMA PRA Category 1 Credits™ for 3 years from the date of publication.

Instructions:

To earn CME/CE credit for this course, you must complete all the following components in the order recommended: (1) Review introductory course content, including Educational Objectives and Faculty/Planner Disclosures; (2) Listen to the audio program and review accompanying learning materials; (3) Complete posttest (only after completing Step 2) and earn a passing score of at least 80%. Taking the course Pretest and completing the Evaluation Survey are strongly recommended (but not mandatory) components of completing this CME/CE course.

Estimated time to complete this CME/CE course:

Approximately 2x the length of the recorded lecture to account for time spent studying accompanying learning materials and completing tests.