Cases & Commentaries

Pregnant With Danger

Commentary By Mark D. Pearlman, MD; Jeffrey S. Desmond, MD

The Case

A 35-year-old woman, 38 weeks pregnant, presented
to the emergency department (ED) in the middle of the night
complaining of left leg pain. She also had some mild lower back
pain, but no other symptoms. Hospital policy stated that all
patients greater than 20 weeks’ gestation should go directly
to labor and delivery unless their problem was clearly unrelated to
the pregnancy. At ED triage, the pain was deemed to be
non-obstetrical in nature, and so she was evaluated in the ED
rather than being sent to labor and delivery.

Physical examination revealed her left leg was
slightly cooler than the right leg but was otherwise unremarkable.
A Doppler venous ultrasound revealed no evidence of deep venous
thrombosis, but there appeared to be decreased blood flow to the
leg in the left-lying position with normal blood flow in other
positions. After many hours of evaluation and observation in the
ED, the pain was diagnosed as musculoskeletal. To facilitate
evaluation by her obstetrician, she was transferred briefly to
labor and delivery. Fetal monitoring was normal and the patient was
discharged home.

The following morning, the patient’s
husband found her dead at home. An emergency cesarean section was
performed in the ED, but both the mother and the infant expired.
Autopsy revealed a ruptured aortic dissection.

The Commentary

This case illustrates the frequent challenges
that practitioners and institutions face in caring for pregnant
women, who often present to EDs with complaints that may or may not
be obstetrical in nature. Optimal evaluation of a pregnant woman
with a non-obstetrical complaint requires an understanding of the
physiology of pregnancy and possible pregnancy-related conditions.
Just as essential, though, are a structured, systematic approach to
caring for these patients, and open, clear lines of communication
between obstetrical and emergency physicians.

Although aortic dissection is an uncommon
disorder in a woman of childbearing age, it is a potentially lethal
condition and so it should be kept in mind in patients with
compatible presentations. In this case, the diagnostic challenges
were made even greater by a relatively unusual presentation, even
for a disease that often presents with non-specific symptoms and
signs. Aortic dissection is thought to result from a tear in the
intima of the aorta often associated with degeneration of the media
from age or other predisposing conditions. Young women who do
develop aortic dissection generally have a risk factor for the
disease, such as Marfan’s syndrome, Ehlers-Danlos syndrome,
hypertension, or bicuspid aortic valve. Pregnancy has been
considered by many to be a risk factor, and some have estimated up
to half of all dissections in women younger than 40 occur during
pregnancy, typically in the third trimester.(1) A
recent review suggests that pregnancy’s role as a risk factor
may be overstated.(2,3)

The clinical presentation of aortic dissection
varies and depends on the location and acuity of the dissection. Of
more than 1,000 patients with aortic dissection included in a large
registry, 76% of patients had chest pain as a presenting symptom,
55% had back pain, and 18% had migrating pain.(4)
The mediastinum was widened on chest radiograph in 60%.(4) The pain is
often described as ripping or tearing in nature. Ten percent of
patients present with isolated leg ischemia as the initial symptom
of an aortic dissection.(5) The location
of the pain may help determine the location of the dissection
(e.g., anterior chest pain is associated with dissection of the
ascending aorta, neck and jaw pain with the aortic arch, pain in
the interscapular area with the descending thoracic aorta, and pain
in the lumbar area or abdomen with involvement below the
diaphragm). When the integrity of one of the branches of the aorta
is compromised, ischemic manifestations usually follow.(1) Dissection
into the iliac or femoral artery probably caused this
patient’s leg pain.

Little published data describe the clinical
presentation of aortic dissection in pregnancy. The presentation of
aortic dissection with initial symptoms of chest or back pain is
similar between genders, though some suggest that dissection in
women may be less likely to present with abrupt onset of
pain.(6)
Pregnancy-related dissection was rare in a group of more than 300
women with aortic dissection.(2) Degeneration
of the collagen and elastin in the aortic media is considered a
predisposing factor for dissection. This, together with increased
wall stress from hypertension or valvular abnormalities (bicuspid
aortic valve), is presumed to lead to intimal tear and dissection.
Hypertension has been associated with 25% to 50% of cases of aortic
dissection in pregnant women. The proximal aorta is the most common
site of pregnancy-associated aortic dissection, with an intimal
tear originating within 2 cm of the aortic valve in 75% of
cases.(7) The aortic
tear commonly occurs during the third trimester or during the first
stage of labor.(8) It should be
noted, though, that maternal and fetal mortality from aortic
dissections in pregnancy have decreased substantially in the past
two decades.(1)

Given its rarity and this atypical presentation,
it is not entirely surprising that the diagnosis of dissection was
missed in this patient. Nevertheless, some problems occurred in the
triage and early management of this patient, and they help shine
some light on more general safety issues regarding caring for
pregnant patients with both obstetrical and non-obstetrical medical
conditions. Five general principles should be addressed when
developing a systematic approach to triage, evaluation, and
management of urgent conditions that occur during pregnancy.

  1. Presenting Complaint
    Pregnant women can present with a myriad of complaints, making
    appropriate triage challenging. Complaints that clearly are
    obstetrical (e.g., episodic lower abdominal pain consistent with
    uterine contractions) should be triaged directly to the labor and
    delivery unit. However, presenting complaints that are
    non-obstetrical in nature or not clearly obstetrically related
    (e.g., chest pain, acute shortness of breath, leg pain) should be
    triaged depending upon the individual institution’s
    resources, consultant availability, and access to diagnostic
    testing. For example, a pregnant patient with acute chest pain or
    sudden shortness of breath may be more appropriately evaluated in
    the ED where there is often better access to diagnostic imaging
    than in labor and delivery. In contrast, pregnant patients in the
    second or third trimester with pregnancy-related complaints would
    be better served with an evaluation in labor and delivery. In
    either situation, clear communication between the emergency
    physician and obstetrician is important. Some examples of
    presenting complaints in pregnant women are included in Table 1 and may
    help guide an institution in developing a triage policy.
  2. Availability of Consultant/Clinical
    Expertise
    For obstetrically related issues, the availability of consultants
    and clinical expertise typically resides within labor and delivery.
    However, in other circumstances, such as presentation with leg
    pain, the expertise of the emergency physician and the rapid
    availability of consultants may make the ED a more appropriate
    setting for evaluation. Depending upon the health system’s
    structure, these resources may be equally available in the labor
    and delivery setting. Local administrators and clinical leaders
    should carefully evaluate their own consultant availability to
    determine how best to develop the system for triage depending upon
    availability of consultant and clinical expertise.
  3. Timeliness of Testing
    Access to advanced imaging and testing should also help guide the
    development of institutional policies. In many settings, diagnostic
    testing such as computed tomography (CT) scanning or ultrasound is
    most expeditiously performed through the ED, whereas in others, an
    inpatient unit such as labor and delivery may be most effective.
    Exposure to radiation has always been a special concern during
    pregnancy. Fetal exposure is generally not a concern until 5 Rads
    (5000 mRad) of exposure has occurred. A CT scan of the abdomen
    typically results in 150-200 mRad fetal exposure, whereas a CT of
    the abdomen and pelvis delivers approximately 2000 mRad to the
    fetus.(9) In other
    words, concern about fetal radiation should not stand in the way of
    appropriate diagnostic evaluation.
  4. Need for Fetal Evaluation
    Most pregnant women with urgent or emergent complaints, unless
    clearly of no threat to the fetus, will undergo formal fetal
    monitoring. In most circumstances, fetal evaluation is done most
    expeditiously and thoroughly in a labor and delivery setting.
    However, maternal circumstances sometimes require prolonged stay in
    an ED (e.g., evaluation of multiple system trauma). In those
    circumstances, depending upon the viability of the fetus and the
    capabilities of the individual health system, arrangements for
    fetal evaluation should be made in the ED. Policies should be
    developed to assure the availability of appropriate clinical skills
    and equipment for continuous fetal monitoring in the ED when
    needed. Every ED should have the capacity to assess fetal heart
    rate, at a minimum by handheld Doppler. In an ED where a pregnant
    woman may require a prolonged stay, a protocol to provide fetal
    monitoring with appropriately trained personnel interpreting the
    monitor tracings should be developed. This can be accomplished by
    having a fetal monitor and labor and delivery nurse come to the ED,
    or, as in our institution, fetal monitoring initiated in the ED
    with remote interpretation of the monitor in labor and
    delivery.
  5. Gestational Age at Presentation
    Some diagnoses are limited to certain timeframes in pregnancy and
    must be considered in the initial evaluation. For example, ectopic
    pregnancies most commonly occur between 5 and 10 weeks’
    gestational age. However, they may occur as late as 14 to 15 weeks
    in interstitial (cornual) pregnancy. Women who present at or near
    the point of fetal viability (approximately 23 to 24 weeks) require
    special consideration, because they could require immediate fetal
    evaluation and potential delivery. Building a policy for triage and
    transfer between the ED and labor and delivery requires
    consideration of gestational age. For example, if a pregnant woman
    at 22 weeks’ gestational age presents to the ED with vaginal
    bleeding and has stable vital signs, she would be transferred to
    labor and delivery (see Table 2,
    scenario III). Nursing-to-nursing communication should take place
    at the time of transfer to assure transmission of information
    (presenting complaint, vital signs, etc.).

The University of Michigan (a tertiary referral
center) has developed a triage protocol for obstetrical patients
presenting to the ED (Table 2). In the
present case, the patient would fall into Category V (medical
complaint not related to pregnancy, greater than 20 weeks'
gestation) and would be evaluated in the ED. Careful attention to
the differential diagnosis, appropriate consultation and the
judicious use of diagnostic testing (e.g., CT scan) might have
detected the aortic dissection before the discharge and subsequent
tragic outcome. When resources and consultants are available, this
system works well, but it would not work as well for a hospital
without available obstetrical consultants. Nevertheless, even in
such hospitals, it can be used as a general guide in developing
institutional policies.

The mother and fetus in this case suffered a
tragic outcome at a hospital that appeared to lack a structured
protocol for triaging obstetric patients. It is unclear whether the
outcome would have been different elsewhere. This case highlights
the need to create clear guidelines for urgent management of
pregnant patients and to maintain clear lines of communication
between providers.

Take-Home Points

  • Aortic dissection is a rare complication
    of pregnancy but carries substantial risk of morbidity and
    mortality.
  • Institutions should establish structured
    protocols for the triage of obstetrical patients presenting with
    emergency complaints.
  • In developing protocols, hospitals must
    consider many factors, including the nature of the complaints,
    consultant and testing availability, the need for fetal monitoring,
    and the fetal age.

Mark D.
Pearlman, MD
Professor and Vice Chair, Department of Obstetrics and
Gynecology
Professor of Surgery
University of Michigan Medical Center

Jeffrey S. Desmond, MD
Clinical Assistant Professor and Service Chief
Department of Emergency Medicine
University of Michigan Medical Center

References

1. Lewis S, Ryder I, Lovell AT. Peripartum
presentation of an acute aortic dissection. Br J Anaesth.
2005;94:496-499.
[
go to PubMed ]

2. Nienaber CA, Fattori R, Mehta RH, et al.
Gender-related differences in acute aortic dissection. Circulation.
2004;109:3014-3021.
[
go to PubMed ]

3. Oskoui R, Lindsay J Jr. Aortic dissection in
women
go to PubMed ]

4. Januzzi JL, Marayati F, Mehta RH, et al.
Comparison of aortic dissection in patients with and without
Marfan's syndrome (results from the International Registry of
Aortic Dissection). Am J Cardiol. 2004;94:400-402.
[
go to PubMed ]

5. Pacifico L, Spodick D. ILEAD--ischemia of the
lower extremities due to aortic dissection: the isolated
presentation. Clin Cardiol. 1999;22:353-356.
[
go to PubMed ]

6. Konishi Y, Tatsuta N, Kumada K, et al.
Dissecting aneurysm during pregnancy and the puerperium. Jpn Circ
J. 1980;44:726-33.
[
go to PubMed ]

7. Immer FF, Bansi AG, Immer-Bansi AS, et al.
Aortic dissection in pregnancy: analysis of risk factors and
outcome. Ann Thorac Surg. 2003;76:309-314.
[
go to PubMed ]

8. Khan IA, Nair CK. Clinical, diagnostic, and
management perspectives of aortic dissection. Chest.
2002;122:311-328.
[
go to PubMed ]

9. Goodsitt MM, Christodoulou EG. Diagnostic
imaging during pregnancy: risks to the fetus. In: Pearlman MD,
Tintinalli JE, Dyne PL, eds. Obstetric and Gynecologic Emergencies:
Diagnosis and Management. New York, NY: McGraw-Hill;
2004:535-548.

Tables

Table 1. Case Examples

These cases are included to test
how an institution’s ED triage policy would handle a variety
of different types of patient presentations. One way to use these
cases would be for both ED and OB service chiefs to review them,
determine how they would handle the triage of these patients, and
be certain that the expectations and outcomes of the triage are
similar.

  1. 21-year-old G2P1 presents to ED with a
    positive pregnancy test at 7 weeks’ gestation, 2 days of
    right lower quadrant pain, and no intrauterine pregnancy on vaginal
    probe ultrasound.
  2. 26-year-old G2P1 was involved in
    high-speed motor vehicle crash at 34 weeks’ gestation. EMS
    calls and notes obvious deformity in right lower extremity and
    vaginal bleeding.
  3. 17-year-old G1P0 with a positive home
    pregnancy test today presents with heavy vaginal bleeding, pulse of
    130, and BP of 68/40.
  4. 33-year-old G3P2 presents at term in
    labor with the presenting part visible at the introitus.
  5. 34-year-old G3P2 at 22 weeks’
    gestation with fever and epigastric and right upper quadrant
    abdominal pain for 5 hours after eating a greasy meal.
  6. 28-year-old G2P1 at 25 weeks’
    gestation slips and falls on ice, twisting her ankle and landing on
    her buttocks. She has ankle pain without deformity.

Table 2. Triage Guidelines for Obstetrical
Patients Presenting to the Emergency Department (Adapted from
University of Michigan Hospitals and Health Centers Emergency
Department Guidelines)

All patients who present to emergency department
triage will have a triage assessment completed and documented prior
to labor and delivery (L&D) transfer

Pregnant Patient with

Flow of Responsibility of Care

I. Trauma

  • Pregnancy of any gestation with
    injury.
  • All pregnant trauma patients >20
    weeks’ gestation with any injury (excluding minor distal limb
    trauma) will be evaluated in the ED with immediate on-site OB
    consult
    Note: Trauma classification is based on the injury to the
    mother

Evaluate in ED with immediate OB
consult

  • Call page operator to activate
    “birth center group page” with message: “OB chief
    to ED for OB trauma”
  • Antenatal fetal monitoring mandatory for
    all pregnant trauma >20 weeks
  • Call L&D and notify them of patient
    and ask to monitor child

II. Emergent obstetrics
problem

  • Imminent delivery: contractions less
    than 5 minutes apart or ruptured membranes
  • Perimortem cesarean deliveries
  • Vaginal hemorrhage related to pregnancy,
    with unstable vital signs
    Note: If contacted before patient arrives at hospital, direct
    ambulance to birth center

Evaluated in ED with immediate OB
consult

  • Call page operator to activate birth
    center group page with message:
    “OB chief to ED for imminent delivery”;
    “OB chief to ED for C-section”; or
    “OB chief to ED for OB-hemorrhage”
  • Page birth center triage RN with arrival
    time and patient information

III. Pregnancy-related chief
complaint: ≥13 weeks’ gestation

  • Vaginal hemorrhage
  • Leakage of fluid consistent with
    ruptured membranes
  • Pain consistent with uterine
    contractions (e.g., midline lower abdominal pains 5-10 minutes
    apart)

Triage directly to birth center,
unless stabilization required in ED

  • ED triage RN will page birth center
    triage RN to give report and notify of patient's impending
    arrival
  • Patient to birth center with ED tech or
    RN, based on patient's condition
  • If stabilization required, call page
    operator to activate birth center group page with message:
    “OB chief to ED for OB assistance”

IV. Medical complaint not related to
pregnancy:

Evaluate in ED

  • Phone consult with OB chief resident or
    GYN resident on call if OB unavailable

V. Medical complaint not related to
pregnancy: >20 weeks’ gestation

If cardiac or respiratory: evaluate in
ED

  • Phone consult with OB chief resident or
    GYN resident on call if OB unavailable
  • Fetal monitoring mandatory

If not cardiac or respiratory: may be
seen in ED

  • ED triage RN to phone consult with OB
    chief resident to discuss transfer to birth center

VI. Bleeding/cramping, hyperemesis
gravidarum:

Evaluate in ED with gynecology
consult

  • Page GYN resident as necessary
  • Courtesy call to OB care provider

VII. Possible or active
chickenpox
Note: Apply surgical mask to patient upon arrival to ED

L&D services REQUIRED (If imminent
delivery, follow II above)

  • Notify birth center triage RN that the
    patient has a rash and is in labor
  • Birth center triage RN will prepare
    L&D room and notify the OB chief resident
  • ED RN transport directly to L&D
    room

L&D services NOT
required—evaluated in ED

  • Phone consult with GYN resident on
    call

VIII. Patient

Evaluate in birth center
triage

IX. Patient >6 weeks
postpartum

Evaluate in ED

  • Birth center triage RN will notify ED
    charge RN to give report and notify of patient’s arrival