Sofija Jackevičiūtė1, Jelena Volochovič1,2
1 Vilnius University, Faculty of Medicine, M. K. Čiurlionio street 21, Vilnius, Lithuania
2 Vilnius University hospital, Santaros clinic, Obstetrics, and Gynecology Center, Santariškių street 2, Vilnius, Lithuania
Abstract
Background: Extralobar pulmonary sequestration is an uncommon congenital lung lesion, very rarely causing severe symptoms prenatally or requiring prompt surgical actions taken. The purpose of this report is to present a unique symptomatic case of extralobar pulmonary sequestration which led to an Ex Utero intrapartum treatment being performed for the first time in Lithuania and followed with successful further treatment of pulmonary pathology.
Case presentation: A nulliparous caucasian patient at 22 years of age was sent to a tertiary level clinic after alarming results were found during routine ultrasound examination at 29+4 weeks of gestation. After a detailed examination, extralobar pulmonary sequestration was diagnosed. Due to severely worsening fetal condition on week 32 of gestation the pregnancy was no longer continued and an Ex Utero intrapartum treatment procedure was performed. The pulmonary pathology later was surgically resected at 6 months of age.
Conclusion: This rare case of extralobar pulmonary sequestration allows us to explore key moments in the diagnostic and treatment pathways of this pathology. Magnetic resonance imaging, which allows evaluating parous patients more precisely than ultrasound imaging, with fetal pulmonary vessels being seen more clearly, is inspected as a necessary step in fetal lung sequestration diagnosis establishment. The Ex Utero intrapartum treatment procedure and how anticipated respiratory challenges of the newborn can be tackled with its implementation leading to timely execution of crucial interventions is researched.
Keywords: intrapartum, treatment, procedures.
Journal of Medical Sciences. July 25, 2022 - Volume 10 | Issue 3. Electronic - ISSN: 2345-0592
139
Medical Sciences 2022 Vol. 10 (3), p. 139-148,
https://doi.org/10.53453/ms.2022.07.17
Ex Utero intrapartum treatment of extralobar pulmonary
sequestration: case report and literature review
Sofija Jackevičiūtė
1
, Jelena Volochovič
1,2
1
Vilnius University, Faculty of Medicine, M. K. Čiurlionio street 21, Vilnius, Lithuania
2
Vilnius University hospital, Santaros clinic, Obstetrics, and Gynecology Center, Santariškių street 2,
Vilnius, Lithuania
Abstract
Background: Extralobar pulmonary sequestration is an uncommon congenital lung lesion, very
rarely causing severe symptoms prenatally or requiring prompt surgical actions taken. The purpose of this
report is to present a unique symptomatic case of extralobar pulmonary sequestration which led to an Ex
Utero intrapartum treatment being performed for the first time in Lithuania and followed with successful
further treatment of pulmonary pathology.
Case presentation: A nulliparous caucasian patient at 22 years of age was sent to a tertiary level
clinic after alarming results were found during routine ultrasound examination at 29+4 weeks of gestation.
After a detailed examination, extralobar pulmonary sequestration was diagnosed. Due to severely
worsening fetal condition on week 32 of gestation the pregnancy was no longer continued and an Ex Utero
intrapartum treatment procedure was performed. The pulmonary pathology later was surgically resected at
6 months of age.
Conclusion: This rare case of extralobar pulmonary sequestration allows us to explore key
moments in the diagnostic and treatment pathways of this pathology. Magnetic resonance imaging, which
allows evaluating parous patients more precisely than ultrasound imaging, with fetal pulmonary vessels
being seen more clearly, is inspected as a necessary step in fetal lung sequestration diagnosis establishment.
The Ex Utero intrapartum treatment procedure and how anticipated respiratory challenges of the newborn
can be tackled with its implementation leading to timely execution of crucial interventions is researched.
Keywords: intrapartum, treatment, procedures.
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140
1. Introduction
Pulmonary sequestration is a rare
congenital pathology with an estimated
incidence of 0,15% to 6,40% of all congenital
abnormalities of the lungs (1). Pulmonary
sequestration can be defined as a formation of
dysplastic vascularized lung tissue that lacks
communication with the tracheobronchial tree
thus failing to properly function and impairing
the respiratory function of healthy lung tissue.
Extralobar sequestrations are predominant in
infants and manifest with severe symptoms early
on (2, 3, 4).
Clinical significance depends
immensely on the size and the location of the
sequestration. Prenatal complications can be as
follows: fetal growth retardation, preeclampsia,
preterm labor, and even miscarriage (1, 3). The
most common postnatal complications a
newborn may display in the case of severe
pulmonary sequestration include respiratory
distress, heart failure, pulmonary hemorrhage,
fetal hydrops, and difficulty feeding (1, 3). Cases
of minor lung sequestrations usually remain
asymptomatic throughout life and are often
diagnosed accidentally in adulthood.
Pulmonary lesions can be visualized on
fetal ultrasound during the second trimester of
pregnancy as of the 16th gestational week. The
prenatal diagnosis of lung sequestration can be
based on Doppler ultrasound imaging as well as
magnetic resonance imaging (MRI) scans
offering the highest accuracy when diagnosing
this pathology in utero. Further treatment
strategy decisions are made upon evaluating the
severity of the sequestration and its potential
threat to the newborn's survival. The measures
taken for timely treatment can be as follows:
conservative surveillance and newborn’s lung
surgery after labor, intrauterine feeding vessel
laser coagulation, an Ex Utero Intrapartum
Treatment, or the pregnancy can be terminated
according to the countries law. This is a report
portraying a case of a successful lung
sequestration Ex Utero Intrapartum Treatment.
2. Case Report
A 22-year-old caucasian nullipara at
29+4 weeks of gestation was presented to tertiary
level Vilnius university hospital Santaros
Klinikos with suspected fetal lung sequestration.
Although the previous fetal ultrasound exam at
18+5 weeks was within normal values, a
thorough fetal ultrasound at 29+4 weeks
described a case of fetal lung pathology:
hydrothorax of the left lung, unidentified echo
positive left side thoracic structure with set blood
circulation (measured size being 2,7x2,4x1,7
cm), seen in Figures 1-3, hence the heart
disposition to the right and the compression of
the left lung itself along with an excess of
amniotic fluid, polyhydramnios. At week 29+4
ultrasound imaging was insufficient for vascular
supply origin identification. Because this step is
essential in pulmonary sequestration diagnosis
differentiation and establishment, we
implemented a more accurate means of imaging,
a fetal MRI for further case specification. 1,5 T
MRI scan was performed using sequences T1,
T2, and DWI and as a result, a much clearer
conclusion of the pathology was drawn. Left
hydrothorax, left supradiaphragmatic formation
(2,6x1,9x1,6 cm in size) with vascular support
from the aorta branching towards the diaphragm,
dextrocardia, and polyhydramnios were detected
and led to suspicion of probable lung
sequestration.
During week 31+5 of gestation, an
ultrasound exam showed the worsening
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condition of fetal bilateral hydrothorax and
polyhydramnios. Following this alarming
change, the standard lung maturation process
was started.
Moving forward, at week 32+2 of
gestation, genetic consultation clarified that no
genetic syndromes or associated abnormalities
were present. The aforementioned case was
specified as an isolated fetal development
anomaly.
A fetal ultrasound on week 32+5 of
gestation showed negative progress of fetal lung
condition (bilateral hydrothorax, compression of
both lungs, and dextrocardia due to the mass
effect given by abnormal pulmonary derivative),
hydrocele, and the potential threat of fetal
hydrops, which led to a decision to no longer
continue this pregnancy. The multidisciplinary
committee agreed upon an Ex Utero Intrapartum
Treatment strategy. During this procedure, a
Cesarean section will be performed and before
pinching the umbilical cord, while it still supplies
the newborn with oxygenated blood, the
pediatric surgeon will perform lung
decompression, aiding the newborn’s respiratory
ability.
Beginning with fetal anesthesia and
general anesthesia for the nullipara, the C-section
was performed ordinarily. After pulling the
newborn out of the womb, while the umbilical
cord was still attached and hadn’t yet been
clamped, the neonate alarmingly did not exhibit
any activity and was seen to be hypotonic and
without elicited reflexes. Therefore, immediately
the intubation, resuscitation of the newborn, and
drainage of the left pleural cavity took place at
the same time. 190 ml of fluid was drained in
total. After 3 minutes and 30 seconds, the
umbilical cord was clamped. The newborn was
evaluated at a 4/5 Apgar score, the umbilical cord
pH was at 7,25, within the normal value, which
indicated that timely action prevented aided in
normal systemic organ function and perfusion.
Overall newborn’s condition was noted severe
thus with CPAP oxygen therapy applied, the
baby boy was transported to a neonatal intensive
care unit where he was closely monitored
onwards.
The placenta was removed, previously
attached to the posterior wall, and sent for a
histology exam, which later did not reveal any
placental pathology. Formerly collected fluid
using pleural cavity draining was sent for
thorough laboratory testing (microbiology,
cytology, biochemistry).
The recovery process of the mother was
smooth, as there were no complications after the
C-section and the surgical wound was healing
properly. Shortly her medical care was continued
in outpatient settings.
Contrarily, promptly after being born,
the neonate arrived at the neonatal intensive care
unit (ICU), where his general condition was
severe because of bilateral hydrothorax,
respiratory failure, respiratory distress
syndrome, heart failure, impaired
microcirculation, prematurity, hypoxia at birth,
low body mass, non-immune hydrops.
Throughout neonates’ stay in ICU, the main
struggle remained its respiratory capability. A
comprehensive examination of the neonate
confirmed lung sequestration diagnosis by
ultrasound (big 22 mm size sequestration with
clearly identified arterial supply), pediatric
cardiologist evaluated positive pulmonary
hypertension progress. After almost two weeks
of care in the neonatal ICU, our patient was
stable enough to be transferred to a neonate unit
for further care and further lung lesion treatment
strategy planning. The patient was discharged
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after 22 days of hospitalization, at 36 weeks. The
newborn has been carefully observed by a
pediatrician, a pediatric surgeon, and a
development specialist since. Elective
thoracoscopic sequestrectomy was performed at
6 months of age under general anesthesia. The
surgery was successful and the postoperative
period was smooth. After histological evaluation
of the resected tissue, a conclusive diagnosis of
extralobar pulmonary sequester was made. As of
15 months of age, the boy is healthy and is
further attentively observed by a pediatrician,
focusing on his overall respiratory function,
infection prevention, comprehensive health, and
development.
Figure 1. A fetal ultrasound, week 31+6. Abnormal derivative in the thoracic cavity (S) and hydrothorax
(H), the white arrow pointing to the aorta.
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Figure 2. Fetal ultrasound with Doppler, week 31+6. Lung sequestration (S), the white arrow pointing to
the feeding vessel branching from the aorta (A).
Figure 3. A fetal ultrasound, week 31+6. Lung sequestration (S) with pedicle (white arrow), causing
dextrocardia (LA- left atrium, RA- right atrium) and hydrothorax (H).
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3. Literature review and discussion
3.1. Prenatal diagnostic approach
To begin with, the first step in fetal
pulmonary lesion diagnostics certainly is
ultrasound imaging. On routine fetal ultrasound
examination, indirect signs of lung sequestration
are polyhydramnios, pleural effusion,
mediastinal shift, fetal hydrops while the direct
signs are the abnormal pulmonary derivative and
the pathognomic arterial supply (14). Lung
sequestration can be seen on fetal ultrasound as
early as the 18th week of gestation, but the
definite diagnosis is based on defining the
abnormal feeding vessel clearly (1, 11). In our
case, on week 29+4 signs of polyhydramnios, left
hydrothorax, cardiac dextraposition, and an
abnormal pulmonary derivative were seen on
ultrasound examination, by week 31+6 we also
were able to visualize the blood vessels
supporting the derivative (Figure 2). Typical
ultrasound imaging paired with Doppler is very
helpful in establishing the suspicion of
pulmonary sequestration when solid, triangle-
shaped echogenic lung mass is detected (11).
Even more accurate views can be obtained with
3D ultrasound especially because the origin and
the direction of the feeding artery can be
distinguished.
The identification of the feeding artery,
branching from the aorta is crucial in the
differential diagnosis of fetal pulmonary lesions,
as the most common congenital lung lesion,
congenital pulmonary airway malformation
(CPAM), also called congenital cystic
adenomatoid malformation, arises from the
normal pulmonary vascular tree contrary to lung
sequestrations (5, 6, 11). Estimated ultrasound
accuracy is 72% (sensitivity 49%, specificity
93%) in pulmonary lesion vascular evaluation,
whereas MRI accuracy is 80% (sensitivity 71%,
specificity 88%), in some studies reaching up to
98% in comprehensive lung anomaly diagnostics
(11, 13). Additionally, compared to MRI,
prenatal ultrasound imaging is a much more
accessible diagnostic measure, able to fulfill
bronchopulmonary sequestration diagnostic
criteria. However, due to numerous factors
jeopardizing the ultrasound diagnostic
capability, such as fetal position, amniotic fluid
deficit, etc., vascular supply sometimes can not
be visualized reliably (11, 12). Although MRI
may not be as widely accessible as ultrasound
imaging, MRI is superior as a better view of
general fetal anatomy can be seen since more
than 60% of extralobar lung sequestrations are
associated with other abnormalities, also
important is the independence of fetal and
placental positions (6, 7, 11). In our case, by the
time fetal pulmonary sequestration was
suspected, ultrasound imaging did not provide
needed vascular identification, thus for case
specification an MRI was performed and feeding
vessels of the derivative were examined and
concluded to be branching from the aorta, hence
extralobar pulmonary sequestration was
diagnosed.
When neither ultrasound nor MRI is
sufficient for feeding vessel recognition,
computed tomography, CT, can be implemented
postnatally with remarkable 90% accuracy
(sensitivity 92%, specificity 88%) surpassing
both US and MRI (11).
3.2. Treatment of choice
Treatment options and strategies follow
a basic principle: the more severe case of
pulmonary sequestration is, the more life-
threatening the symptoms become, requiring
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increasingly more complicated clinical tactics of
choice.
Initially, this uncommon pathology
very rarely does call for prenatal or perinatal
treatment as a substantial part of fetal lung
sequestrations are asymptomatic or are seen to
resolve (8). Nevertheless, if respiratory problems
are not to be expected, early delivery or a C-
section are not indicated (11). Currently,
consensus for optimal monitoring of
asymptomatic patients does not exist, however
regular monitoring by thoracic imaging (X-ray,
CT or MRI) is recommended for small and
asymptomatic lung lesions (18).
When neonatal respiratory
complications are probable, delivery should be
planned carefully together with neonatology
experts and pediatric surgeons in a tertiary level
center where required help and experience are
available in need of urgent resuscitation or
intervention as was done in our case (11).
Prenatal treatment options include
thoracoamniotic shunting and intrafetal laser
coagulation. Prenatal hydrops management is
essential for healthy lung tissue development,
that is why thoracoamniotic shunt placement or
laser coagulation helps reduce the adverse
consequences pulmonary sequestrations have on
residual healthy lung maturation.
Treatment using a thoracoamniotic
shunt hasn’t shown promising results in cases of
severe fetal lung sequestrations used for lung
decompression, however, it is encouraged when
signs of hydrops are seen before week 30 of
gestation (1, 4). Since our patient had severe lung
sequestration and only since week 32 hydrops
was suspected, a thoracoamniotic shunt was not
selected as a treatment strategy. According to one
relatively large cohort study, only 59% of fetuses
survived thoracoamniotic shunting and the main
prognostic markers associated with poor survival
were polyhydramnios, hydrops, mediastinal
shift, and shunt-birth interval lower than 4
weeks, all of which were seen in our case study
(21).
Intrafetal laser coagulation aids fetal
lung condition by reducing sequester size,
increasing total normal lung tissue volume, and
reversing hydrops and pleural effusion in more
than 75% of reported cases (18). In comparison
with thoracoamniotic shunt, laser ablation has
shown better results in bronchopulmonary
sequestration treatment as total lesion regression
was seen more often (18). Although sometimes a
second ablation procedure is needed, higher
gestational age is seen with laser ablation rather
than shunt placement (19). Reasons, why laser
coagulation was not selected in our case, are as
follows: it was too late time-wise in the
pregnancy to expect an effect of sequestration
reduction after the procedure; fetal complications
were already severe; the vascular location was
particularly risky for coagulation, it being so
close to the aorta.
An option for perinatal treatment exists
as well. Perinatally, Ex Utero intrapartum
therapy (EXIT) procedure can be applied in cases
of large pulmonary sequestrations, hybrid
lesions, and CPAM (17). When the fetal
respiratory function is compromised, EXIT
provides very valuable time for life-saving
interventions (pleural drainage, ECMO
cannulation, chest decompression, mass
excision, etc.) during C-section and helps to
delay surgery (17). This procedure requires a
high level of experience, however, the general
survival rate of fetuses is 90% (17, 20). In our
case, the choice to perform EXIT was made upon
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evaluating the rapidly worsening fetal condition,
prematurity, and the high probability of
respiratory decompensation after birth.
Furthermore, prenatal and perinatal
interventions are focused on symptom
management, targeting the complications of lung
sequestration. Though sometimes sequestrations
are seen to resolve completely after shunting or
vascular coagulation, the sequestrations
themselves may still cause symptoms postnatally
and remain in need of resection later on (21).
Postnatal extralobar pulmonary sequestration
resection shows excellent results as well as low
complication rates (11, 18). The notion is that
when applicable and indicated, resection is an
excellent strategy with lobectomy being the
superior choice to segmentectomy (4, 8, 14, 17).
Surgery should always be done on symptomatic
patients 6 to 12 months old when no coinciding
pathology interferes with the surgery (18).
Resection is recommended for the prevention of
infection, hemorrhage, malignancy, and curative
purposes even for asymptomatic or low-risk
patients (11, 14). Although the complication rate
isn’t yet clearly established, infection is the most
common unresected pulmonary sequestration
complication, usually requiring urgent surgery
(18). For preventative and curative reasons
elective postnatal sequestrectomy was performed
in our case when the patient was 6 months old.
4. Conclusions
In this case study, prenatal ultrasound
presented a suspicion of pulmonary dysplasia
with the possibility of it being lung sequestration
and an MRI helped to identify more accurate
size, evaluate the anatomy of blood vessels, and
conclude it as an extralobar pulmonary
sequestration. In this case, the decision to
perform an EXIT procedure and immediately
drain the pleural cavity was made upon
evaluating the worsening clinical condition of
the fetus. With this procedure performed we were
able to manage the anticipated life-threatening
respiratory failure and postpone surgical
resection to the recommended age for resection
and later perform the sequestrectomy
successfully.
This case report and literature review
highlight the importance of prenatal diagnostic
precision and clinical action planning. With this
novel procedure implementation, we were able to
expand our clinic‘s experience and, most
importantly, save a child‘s life.
Informed Consent
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