27 Dec 2019

Anesthesia during Pregnancy

While many women get through multiple pregnancies without complications, pregnancy and human gestation is a highly risky process. Some common complications of pregnancy include high blood pressure, gestational diabetes, hyperemesis gravidarum (extreme nausea and vomiting), anemia, infections, preeclampsia, preterm labor, pregnancy loss or miscarriage, stillbirth and more.1 Additionally, drugs, alcohol, tobacco and some prescription medications can harm the health of the mother as well as the embryo/fetus during gestation.2 Prenatal care and caution among physicians are often vital to the success of a pregnancy.3 Since the 1960s, researchers have expressed that anesthesiology practitioners in particular must be vigilant with pregnant patients.4,5 For non-obstetric surgery during pregnancy, anesthesia providers must aim to protect maternal safety, maintain the pregnant state and ensure the best possible fetal outcome.4 Pregnant patients can present complex cases, and it is the anesthesiologist’s duty to provide proper perioperative care.

Each year, over 75,000 pregnant women in the United States undergo non-obstetric surgery.6 Operations include those directly related to pregnancy (e.g., treatment for cervical weakness), those related to general reproductive health (e.g., removing an ovarian cyst) and those unrelated to gestation (e.g., appendectomy).6 Though the relative safety of non-obstetric surgery and anesthesia in pregnancy has been well-established from decades of research,6-9 anesthesia providers are still responsible for preventing complications in pregnant patients. The decision to proceed with a surgery is made by health professionals from various specialties, such as obstetricians, anesthesiologists, surgeons and perinatologists.4 Then, before surgery, the anesthesiology practitioner selects the anesthesia modality (i.e., regional or general) and appropriate anesthetic drugs based on the type and site of the surgery.4 Substances with teratogenic or fetotoxic properties should be avoided, including opioids.10 While acetaminophen is a viable option to alleviate pain, nonsteroidal anti-inflammatory drugs (NSAIDs) should be used minimally.10 When opioids must be used, tramadol serves as a low-potency option, while morphine provides increased pain relief with other addiction-related consequences.10 Depending on the type of surgery, election to perform the procedure and selection of medication are two decisions crucial to the anesthesiologist’s practice.4

During surgery, the anesthesia provider’s role shifts to monitoring and preventing complications. In order to maintain maternal and embryonic/fetal homeostasis,4 vital signs should be maintained at a consistent level. Changes in maternal positioning can have large effects on blood pressure and other hemodynamics, so the anesthesiologist should make sure repositioning is gradual and meticulous.4 Also, ventilation and proper oxygenation are crucial to the health of the mother and embryo/fetus.4 Airway management can be difficult during pregnancy, and the anesthesia provider should aim to limit air pockets within the abdominal cavity, which could otherwise cause damage to the mother and embryo/fetus.11 The anesthesia provider should be prepared to act if resuscitation is required and follow standard life support protocols.4 Preterm labor or spontaneous abortion may also occur due to the stress of surgery.8 When premature labor begins, the anesthesiologist will administer tocolytics (also known as anti-contraction medications or labor suppressants) to preserve the pregnancy.4 Some researchers argue that prophylactic tocolytic administration may be effective in preventing preterm labor if surgery takes place in the third trimester.4 Clearly, anesthesiology practitioners have various duties throughout surgery for pregnant patients, and thus must be highly attentive.

Anesthesia provision during pregnancy can be complex. Though some researchers have found that anesthesia administration to mice causes neurological issues in offspring,12,13 the evidence for anesthesia-related gestation issues and maternal risks is limited in humans.6,7,14 However, certain analgesics such as opioids can cause withdrawal symptoms in neonates.15 Future research should aim to improve upon best practices in anesthesia during pregnancy and non-medication alternatives for pain management.

1.         Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD). What are some common complications of pregnancy? 2019.

2.         Cleveland Clinic. Medicine Guidelines During Pregnancy. January 1, 2018; https://my.clevelandclinic.org/health/drugs/4396-medicine-guidelines-during-pregnancy.

3.         Krueger PM, Scholl TO. Adequacy of prenatal care and pregnancy outcome. Journal of the American Osteopathic Association. 2000;100(8):485.

4.         Upadya M, Saneesh PJ. Anaesthesia for non-obstetric surgery during pregnancy. Indian Journal of Anaesthesia. 2016;60(4):234–241.

5.         Shnider SM, Webster GM. Maternal and fetal hazards of surgery during pregnancy. American Journal of Obstetrics & Gynecology. 1965;92(7):891–900.

6.         Kuczkowski KM. Nonobstetric Surgery During Pregnancy: What Are the Risks of Anesthesia? Obstetrical & Gynecological Survey. 2004;59(1):52–56.

7.         Mazze RI, Kallén B. Reproductive outcome after anesthesia and operation during pregnancy: A Registry study of 5405 cases. American Journal of Obstetrics and Gynecology. 1989;161(5):1178–1185.

8.         Duncan PG, Pope WD, Cohen MM, Greer N. Fetal risk of anesthesia and surgery during pregnancy. Anesthesiology. 1986;64(6):790–794.

9.         Balinskaite V, Bottle A, Sodhi V, et al. The Risk of Adverse Pregnancy Outcomes Following Nonobstetric Surgery During Pregnancy: Estimates From a Retrospective Cohort Study of 6.5 Million Pregnancies. Annals of Surgery. 2017;266(2):260–266.

10.       Ninke T, Thoma-Jennerwein S, Blunk J, Annecke T. Anesthesia and pain management during pregnancy. Anaesthesist. 2015;64(5):347–356.

11.       Heesen M, Klimek M. Nonobstetric anesthesia during pregnancy. Current Opinion in Anaesthesiology. 2016;29(3):297–303.

12.       Chung W, Yoon S, Shin YS. Multiple exposures of sevoflurane during pregnancy induces memory impairment in young female offspring mice. Korean Journal of Anesthesiology. 2017;70(6):642–647.

13.       De Tina A, Palanisamy A. General Anesthesia During the Third Trimester: Any Link to Neurocognitive Outcomes? Anesthesiology Clinics. 2017;35(1):69–80.

14.       Tolcher MC, Fisher WE, Clark SL. Nonobstetric Surgery During Pregnancy. Obstetrics & Gynecology. 2018;132(2):395–403.

15.       Cramton REM, Gruchala NE. Babies breaking bad: Neonatal and iatrogenic withdrawal syndromes. Current Opinion in Pediatrics. 2013;25(4):532–542.