First Trimester Pregnancy Emergencies: Recognition and Management

Table of Contents

 

When a first-trimester-pregnant patient presents to the ED, emergency clinicians must consider the life and health of both the mother and the fetus in diagnosis and management. Abdominal pain, bleeding, urinary tract infection, and nausea and vomiting are common conditions in the differential for pregnant patients – as well as for patients who don’t yet know they’re pregnant. This issue provides the latest evidence on managing the most common emergencies in the first trimester.

Confirming an intrauterine pregnancy is key: how are hCG levels correlated with ultrasound results? What are the best imaging studies if it’s unclear?

What are the key features of the physical examination that will tell you whether a miscarriage has occurred or may occur?

What can you say when a patient asks, “will I lose my baby?” What can say when the answer is “yes”?

Should you screen routinely for UTI? Asymptomatic bacteriuria? When is admission required?

What are the immediate actions to take when ectopic pregnancy is on the differential?

Is there any good treatment for nausea and vomiting in pregnancy? What’s the best stepwise approach to managing this common condition?

What are the cautions when imaging pregnant patients?

1. Abstract
2. Case Presentations
3. Introduction
4. Critical Appraisal of the Literature
5. Etiology and Pathophysiology
   1. Miscarriage
   2. Ectopic Pregnancy
   3. Nausea and Vomiting of Pregnancy (and Hyperemesis Gravidarum)
   4. Asymptomatic Bacteriuria and Urinary Tract Infections
   5. Acute Appendicitis in Pregnancy
6. Differential Diagnosis
7. Prehospital Care
8. Emergency Department Evaluation
   1. History
   2. Physical Examination
9. Diagnostic Studies
   1. Urine Pregnancy Testing
   2. Diagnostic Studies in Miscarriage and Ectopic Pregnancy
      1. Imaging Studies
      2. Rh Status
   3. Diagnostic Studies in Nausea and Vomiting of Pregnancy
   4. Diagnostic Studies in Asymptomatic Bacteriuria and Urinary Tract Infections
   5. Diagnostic Studies in Acute Appendicitis in Pregnancy
10. Treatment
    1. Prevention of Rh Alloimmunization
    2. Miscarriage
       1. Managing Communication Around Pregnancy Loss
    3. Pregnancy of Unknown Location and Ectopic Pregnancy
    4. Nausea and Vomiting of Pregnancy
    5. Asymptomatic Bacteriuria and Urinary Tract Infections
    6. Acute Appendicitis in Pregnancy
11. Special Circumstances
    1. Ionizing Radiation in Pregnancy
12. Controversies and Cutting Edge
    1. Pregnancy Testing Using Whole Blood With Point-of-Care Testing Devices
    2. Expectant Management of Ectopic Pregnancy
13. Disposition
14. Summary
15. Risk Management Pitfalls for Emergency Department Management of First-Trimester Pregnant Patients
16. Time- and Cost-Effective Strategies
17. Case Conclusions
18. Clinical Pathway for Emergency Department Management of Nausea and Vomiting of Pregnancy
19. Tables and Images
    1. Table 1. Differential Diagnosis for Abdominal Pain in Pregnancy
    2. Table 2. Types of Miscarriage and Associated Physical Examination and Ultrasound Findings
    3. Table 3. Fetal Radiation Doses Associated With Common Radiologic Examinations
    4. Figure 1. Sites of Ectopic Pregnancy Implantation
    5. Figure 2. Changes in hCG Levels Over 48 Hours in Patients With Intrauterine Pregnancies, Ectopic Pregnancies, and Spontaneous Abortion / Miscarriage
    6. Figure 3. Definitive Intrauterine Pregnancy on Ultrasound
    7. Figure 4. Definitive Ectopic Pregnancy on Ultrasound
20. References

Abstract

Timely management of patients presenting to the ED while in their first trimester of pregnancy can improve outcomes for both the patient and the fetus. Common obstetric problems encountered include vaginal bleeding and miscarriage, ectopic pregnancy and pregnancy of undetermined location, and nausea and vomiting of pregnancy, including hyperemesis gravidarum. Optimal diagnostic approaches and management strategies are covered, including which antiemetics are safe to give in pregnancy. Common nonobstetric problems include asymptomatic bacteriuria, urinary tract infections including pyelonephritis, and acute appendicitis. This article also reviews the various imaging modalities available for pregnant patients and reviews the risks of ionizing radiation as well as various contrast media.

Case Presentations

Your first patient of the shift is a 23-year-old woman whom the nurse has rushed into the resuscitation bay due to hypotension and altered mental status. The patient's blood pressure is 70/40 mm Hg, with a heart rate of 70 beats/min, and she states that she has had abdominal pain and vaginal bleeding since this morning. You wonder what would be the fastest way to get this patient diagnosed and treated…

The patient in the room next door is a 19-year-old woman who presents due to light vaginal spotting for the past few hours. She says she came in because she has been trying to get pregnant for months, and finally had a positive pregnancy test yesterday. This is her first visit to a doctor since learning of her pregnancy. She is tearful, and asks, “Does this mean I am going to lose my baby?” You are not quite sure how to answer her question, and you ask yourself what tests need to be done today in the ED...

Later that shift, you evaluate a 26-year-old woman who has a confirmed intrauterine pregnancy at 11 weeks’ gestation and presents for fever, dysuria, and right flank pain. An ultrasound was performed in triage that showed bilateral mild hydronephrosis. You are not sure what to make of that finding, which antibiotics would be safe for treatment, and whether she can be managed as an outpatient…

Introduction

Patients in their first trimester of pregnancy frequently present to the emergency department (ED) with both obstetric and nonobstetric complaints that range from benign to life-threatening for both mother and fetus. Managing these patients is an important skill, but a recent survey demonstrated that only 56% of emergency medicine residents felt they had adequate exposure to obstetric emergencies. On a multiple-choice test covering knowledge of obstetric emergencies, a mean of 58% of items were answered correctly.¹ This identifies an important area for further education and training, as timely diagnosis and appropriate management can improve outcomes.

Common obstetric problems in the first trimester of pregnancy include vaginal bleeding and the spectrum of miscarriage (experienced by 7%-27% of pregnant patients)², nausea and vomiting (85%)³, hyperemesis gravidarum (3%), and ectopic pregnancy (2%)⁴. Common nonobstetric problems include appendicitis and urinary tract infections (UTIs). The most recent report on pregnancy-related mortality, published in 2017 and encompassing 2011-2013 data for pregnancies in the United States, showed a stable rate of 17 deaths per 100,000 pregnancies, but with significant racial-ethnic disparities.⁵

This issue of Emergency Medicine Practice reviews important issues that affect patients in their first trimester, management pearls and pitfalls, and a review of the literature surrounding current recommendations.

Critical Appraisal of the Literature

Medical Subject Headings (MeSH) via PubMed were searched for pregnancy trimester, first (14,929 articles), hyperemesis gravidarum (1379 articles), ectopic pregnancy (13,953 articles), and abortion, spontaneous (34,256 articles). These articles were further limited to English language only, human subjects, and then divided into reviews and clinical trials.

Guidelines from the American College of Obstetricians and Gynecologists (ACOG) were reviewed, including evidence-based Practice Bulletins on critical care in pregnancy (2016)⁶, medical management of first-trimester abortion (2014)⁷, tubal ectopic pregnancy (2018)⁸, nausea and vomiting of pregnancy (2018)⁹, and prevention of RhD alloimmunization (2017)¹⁰. ACOG Committee Opinions on the risk of birth defects with antibiotics for UTI (2017)¹¹ and guidelines for imaging in pregnancy (2017)¹² were also reviewed. The American College of Radiology Practice Parameter for imaging of pregnant women (2013)¹³, a consensus-based guideline based on the review of the available evidence, was reviewed, along with the 2005 guidelines from the Infectious Diseases Society of America (IDSA) on asymptomatic bacteriuria.¹⁴

The Cochrane Database of Systematic Reviews has reviews on interventions for nausea and vomiting in pregnancy (2015)¹⁵, hyperemesis gravidarum (2016)¹⁶, antibiotic regimens for asymptomatic bacteriuria (2010)¹⁷, UTIs (2011)¹⁸, expectant versus surgical management of miscarriage (2012)¹⁹, and medical treatments for incomplete miscarriage (2017)²⁰. Most of these reviews include multiple randomized controlled trials, and the data are generally good for these topics. The American College of Emergency Physicians (ACEP) released a 2017 update on their Clinical Policy, “Critical Issues in the Initial Evaluation and Management of Patients Presenting to the ED in Early Pregnancy,” although no new significant updates were added since their previous 2012 recommendations.^21,22

The relevant literature that guides ED management of first trimester emergencies is, overall, very good, and many of the recommendations in this issue of Emergency Medicine Practice can be made based on robust data. Some data, such as the utility of a pelvic examination when an ultrasound is performed, are underpowered to detect potential small, but true, differences in outcomes and are areas for further study.

Risk Management Pitfalls for Emergency Department Management of First-Trimester Pregnant Patients

3. “The patient was 11 weeks’ pregnant and had pyelonephritis; she had a fever and was vomiting, but looked okay, so I sent her home with antibiotics.”

Until further data support initial outpatient management of pyelonephritis, it is best to admit all pregnant patients with pyelonephritis for an initial course of IV antibiotics.

5. “My patient was 10 weeks’ pregnant and had nausea, so I sent her home with 60 tablets of ondansetron.”

Although the risk of birth defects with maternal ondansetron exposure is low, there are safer alternatives for treatment of nausea and vomiting in pregnancy. Pyridoxine or pyridoxine with doxylamine should be considered first-line therapy.

9. “My patient was hypotensive and had a positive pregnancy test. I could not see an IUP, but she had free intraperitoneal fluid. I figured I would rule out other diagnoses with a CT scan, but she coded in the scanner!”

An unstable pregnant patient without an identified IUP with abdominal pain and/or vaginal bleeding has an ectopic pregnancy until proven otherwise. Unstable patients should proceed immediately to surgical management with an obstetrician.

Tables and Images

References

Evidence-based medicine requires a critical appraisal of the literature based upon study methodology and number of subjects. Not all references are equally robust. The findings of a large, prospective, randomized, and blinded trial should carry more weight than a case report.

To help the reader judge the strength of each reference, pertinent information about the study, such as the type of study and the number of patients in the study is included in bold type following the references, where available. In addition, the most informative references cited in this paper, as determined by the author, are highlighted.

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71. Fromm C, Likourezos A, Haines L, et al. Substituting whole blood for urine in a bedside pregnancy test. J Emerg Med. 2012;43(3):478-482. (Prospective blinded study; 633 patients)
72. Gottlieb M, Wnek K, Moskoff J, et al. Comparison of result times between urine and whole blood point-of-care pregnancy testing. West J Emerg Med. 2016;17(4):449-453. (Prospective observational study; 265 patients)
73. Silva PM, Araujo Junior E, Cecchino GN, et al. Effectiveness of expectant management versus methotrexate in tubal ectopic pregnancy: a double-blind randomized trial. Arch Gynecol Obstet. 2015;291(4):939-943. (Randomized trial; 23 patients)
74. Jurkovic D, Memtsa M, Sawyer E, et al. Single-dose systemic methotrexate vs expectant management for treatment of tubal ectopic pregnancy: a placebo-controlled randomized trial. Ultrasound Obstet Gynecol. 2017;49(2):171-176. (Multicenter randomized trial; 80 patients)