Pre anesthesia pregnancy screening: an imperative or a bubbe meise? Ethical considerations part one
Lynne G. Maxwell MD, Myron Yaster MD
Mandatory preoperative pregnancy screening/testing of adolescents, and indeed of all potentially pregnant patients, is a source of frequent anxiety and sometimes awkwardness for patients, families, preop nurses, surgeon/proceduralists, and anesthesiologists. Most health systems have strict mandatory requirements for preoperative pregnancy testing for all females (and perhaps transgender males) beginning at menarche or age 12. While this is well-established practice in many institutions, including pediatric hospitals, the scientific, medico-legal and ethical basis for such policies is not so clearcut. Today’s PAAD by Jackson et al.1 in the May 2024 issue of Anesthesia and Analgesia is a must read for all of you. We simply can’t do it the justice it deserves in a single PAAD, which by design are 5-6 minute reads. Indeed, because it is so important, we’ve decided to expand our review and split it into 2 parts. It should be noted that their review encompasses issues of pregnancy screening in all patients, with only a small reference to issues in adolescents. We would urge all of you to read this article in its entirety and feature it in your morning conferences, departmental grand rounds, journal clubs, or in a future national meeting.
For me (MY), one of the most important elements of this article is its detailed discussion of the teratogenicity, or better said the lack of teratogenicity, of the drugs we use in anesthesia. This question goes far beyond pregnancy testing and is an issue for all of the women who work in the operating rooms and PACUs while pregnant. We won’t be discussing this in today’s PAAD but think it touches a nerve in all of your practices and today’s article can potentially be used as a jumping off point in your internal discussions on this topic.
Original article
Jackson S, Hunter J, Van Norman GA. Ethical Principles Do Not Support Mandatory Preanesthesia Pregnancy Screening Tests: A Narrative Review. Anesth Analg. 2024 May 1;138(5):980-991. doi: 10.1213/ANE.0000000000006669. Epub 2023 Oct 6. PMID: 37801601.
The informed consent process is a legal requirement that honors respect for patient autonomy and is founded in the US constitutional principles of privacy and noninterference. Jackson et al.1 frame the issue of mandatory preanesthesia urine pregnancy testing through the ethical lens of patient autonomy, stating that it “does not adequately respect patient autonomy, is potentially coercive, and has the potential to cause harm medically, psychologically, socially and financially.” “Autonomous patients have rights, legally and ethically, to consent to or refuse tests and treatments, and furthermore to not be coerced into submitting to medical tests and treatments. At a minimum, a physician should inform the patient what tests the physician wants to order and how those tests might be of potential benefit or harm, and then ask for the patient’s permission to perform them.”1
Aside from the ethical concerns, urine pregnancy testing may have both false positive and false negative results, especially in early pregnancy, and positive results may persist after early pregnancy loss, whether caused by miscarriage or abortion. I (LGM) have encountered such a situation in which the pregnancy test of a 17 yo was positive. When she was informed of the result and that her surgery would have to be cancelled, she stated that she had had an abortion two weeks before. With her permission, this fact was confirmed by the facility at which the procedure was performed, but the awkwardness of the situation might have been avoided if the pregnancy testing had not been performed.
In 2003, ASA members on the Committee on Ethics and Committee on Practice Parameters published an article in the ASA Newsletter (). in which they declared that the “state of pregnancy is very personal information that belongs to the patient, and it does not alter her right to proceed with anesthesia and surgery if she so desires. Therefore, pregnancy testing should be offered to patients but should not be required by physicians unless there is a compelling medical reason to know whether the patient is pregnant.2 Beyond not being ethical, it also may not be legal to test a patient for pregnancy without her consent. Minors are even more complex in this regard because states have disparate statutes defining whether parents are entitled to the results of their minor child’s pregnancy testing.” Despite these statements of concerns through the years, it has become dogma that preanesthesia pregnancy screening is mandatory to protect not only a potential fetus, but also to protect the anesthesiologist from medico-legal liability if an anesthetic is administered and the patient is later found to have been pregnant. Mandatory testing in adolescents has been suggested to avoid the awkwardness of asking these patients about their menstrual/sexual history and whether they could be pregnant. As noted by Jackson et al., “adolescents are likely to be reticent to reveal a history of …sexual activity, especially in the presence of their parents.” The awkwardness may be share by those asking the questions as well. These are questions that are frequently part of preanesthetic history in adult females.
The traditional concerns supposedly addressed by preanesthesia pregnancy testing have been preventing fetal harm, mitigating medicolegal claims due to pregnancy loss and fetal malformations, and it is a standard of care. Let’s look at these in greater detail
Preventing fetal harm
“The cause for most congenital abnormalities is unknown: only approximately 25% of early human pregnancy losses are associated with detectable gene or chromosomal abnormalities. Thus, the presence of an anomaly in a newborn exposed to anesthesia in utero is not scientifically sufficient evidence of cause and effect.”1 The authors provide evidence from multiple large studies that show that “despite widespread belief to the contrary, no anesthetic drug has been proven to be a human teratogen when used in standard concentrations at any gestational age”.2,3 Other studies found no increase in miscarriage in patients who underwent anesthesia and surgery during pregnancy, although a slight increase in risk was seen in patients in whom the surgery was intra-abdominal, suggesting that the site of surgery was more important than the anesthetic.2,4
“Nitrous oxide has teratogenic effects in some nonhuman species, but large, retrospective human studies have failed to show a correlation between exposure to nitrous oxide during pregnancy and teratogenicity, even in the first trimester4.”1 Local anesthetics (other than cocaine) and muscle relaxants have no effects in clinical doses.
Fetal brain development and in utero exposure to anesthetics
The authors point to a 2021 joint statement of the American College of Obstetricians and Gynecologists and the ASA which states “There is no evidence that in utero human exposure to anesthetic or sedative drugs has any effect on the developing fetal brain and there are no animal data to support an effect with limited exposures less than 3 hours in duration.”4 We’ve discussed the effects of anesthetic agents on the developing brain many times in the PAAD and at national meetings. We, like the authors of today’s PAAD think the animal models have a questionable correlation to human pregnancy and has no scientific substantiation.
Medicolegal concerns
Although this has long been identified as an area of liability for anesthesiologists, in reality “the medicolegal risk to anesthesiologists has been practically nonexistent,” as documented by the ASA Closed Claims Project, in which the few successful claims were in cases in which a pregnancy test was ordered but the anesthesiologist didn’t review the results, and a case in which a surgeon performed hysterectomy without ordering a preoperative pregnancy test. Indeed, the ASA Committee on Quality Management and Departmental Administration concluded “other than for surgical indications, routine pregnancy testing may pose greater medico-legal risk to anesthesiologists due to failure to check the result or failure to document informed consent of [perhaps minimal] risk of miscarriage prior to elective surgery ” (italics added).5”1
Preanesthesia pregnancy testing is not a standard of care (contrary to popular belief)
Contrary to prevailing wisdom, “the ASA Task Force on Preoperative Testing and the ASA Committee on Ethics jointly recommend that anesthesiologists offer the choice of preoperative pregnancy testing to any ‘female’ patient who may desire it, explain the potential risks and benefits, and obtain informed consent or refusal for the test.3 The most recent amendment of this document (October 13, 2021) states: “Pregnancy testing may be offered to female sex patients of childbearing age and for whom the result would alter the patient’s management, but testing should not be mandatory. Informed consent or assent of the risks, benefits, and alternatives related to preoperative pregnancy testing should ideally be obtained. Best practice may employ shared decision-making between patients and providers.”6 The ASA Committee is now considering revising the wording of this recommendation to include transgender men.
In tomorrow’s part 2 we will discuss issues concerning the accuracy of pregnancy testing as alluded to in Lynne’s anecdote, informed consent in adolescents, the harms of pregnancy testing and conscientious objection.
What do you think? Do you want to open this can of worms at your institution, or leave things as is? Send your thoughts and comments to Myron who will post in a Friday reader response.
References
1. Jackson S, Hunter J, Van Norman GA. Ethical Principles Do Not Support Mandatory Preanesthesia Pregnancy Screening Tests: A Narrative Review. Anesthesia and analgesia 2024;138(5):980-991. (In eng). DOI: 10.1213/ane.0000000000006669.
2. 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. (In eng). DOI: 10.1097/sla.0000000000001976.
3. American College of Obstetricians and Gynecologists, opinion ASoACoop. Nonobstetric surgery during surgery. Committee opinion; number 775' April 2019, Updated 2019. (https://www.acog.org/clinical/clinical-guidance/committee-opinion/articles/2019/04/nonobstetric-surgery-during-pregnancy).
4. Aylin P, Bennett P, Bottle A, et al. Health Services and Delivery Research. Estimating the risk of adverse birth outcomes in pregnant women undergoing non-obstetric surgery using routinely collected NHS data: an observational study. Southampton (UK): NIHR Journals Library Copyright © Queen’s Printer and Controller of HMSO 2016. This work was produced by Aylin et al. under the terms of a commissioning contract issued by the Secretary of State for Health. This issue may be freely reproduced for the purposes of private research and study and extracts (or indeed, the full report) may be included in professional journals provided that suitable acknowledgement is made and the reproduction is not associated with any form of advertising. Applications for commercial reproduction should be addressed to: NIHR Journals Library, National Institute for Health Research, Evaluation, Trials and Studies Coordinating Centre, Alpha House, University of Southampton Science Park, Southampton SO16 7NS, UK.; 2016.
5. American Society of Anesthesiologists Committee on Quality Management and Departmental Administration. Prenancy testing prior to anesthesia and surgery.