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410
Fig. 33.7 Apical ve-Chamber view of the patient with
unrepaired Tetralogy of Fallot, demonstrating overriding
aorta over VSD. Left atrium (LA) and left ventricle (LV)
associated with aorto-pulmonary collateralization and these large collaterals are potentially
visualizable. Additionally, ASDs are possible and
are evaluated for features that should be recognized in critical care echocardiography include
the assessment of right ventricular function and
its loading status given the nature of the
abnormality.
E. Su and S. Flores
Bicuspid Aortic Valve
At 1% of the population, this is one of the most
common congenital heart defects. It may occur
alone or with other defects. In patients with
bicuspid aortic valve, fusion of the left and the
right coronary leaets is most common. However,
fusion of the right and the noncoronary leaets is
associated with greater valve dysfunction. These
patients may develop valve calcication, stenosis
and/or regurgitation, subsequently resulting in
root dilatation. Bicuspid aortic valve is also an
independent risk factor for aortic dissection as
well as endocarditis.
Typical echo targets for assessment of bicuspid aortic valve include detailed views of valve
morphology. These consist of a variety of views
including those in the parasternal short axis at the
aortic valve level that can identify fusion of the
valve leaets (Figs.33.8, 33.9, 33.10, and 33.11).
Parasternal long axis views focusing on the aortic
valve can help identify dilation of the aortic root
as well as valvular insufciency and abnormal
leaet excursion. A complete evaluation of left
ventricular functional exam is indicated given the
effect of aortic stenosis on afterload and regurgitation on preload. There is the potential for a
Type A (DeBakey I or II) dissection involving the
ascending aorta and this can potentially be evaluated using arch views..
Features that need to be recognized in critical
care echocardiography include a signicantly
dilated aortic root and left ventricular function.
Problems Causing Obstruction
toBlood Flow
Anomalies of the left heart outow lead to
obstruction of systemic perfusion that lead to
shock and heart failure. In the adult, the degree of
shock is either survivably mild or progressively
worsens over the lifespan.
Coarctation oftheAorta
Coarctation occurs in 4% of congenital heart disease and can be repaired using a variety of techniques. These include end to end anastomosis, a
subclavian ap repair using a segment of sacriced subclavian artery to widen the coarctation
site, patch angioplasty, or an interposition graft
for restoring aortic patency. The physiology of
33 Adult Congenital Heart Disease
Fig. 33.8 Parasternal
short axis view at the
aortic valve level of a
16-year-old male
demonstrating bicuspid
aortic valve and fusion
of the right and left
aortic valve leaets.
Aorta (Ao) and left
ventricle (LV)
Fig. 33.9 Color
Doppler of Parasternal
long axis view of
16-year-old male with
bicuspid aortic valve
demonstrating moderatesevere aortic
insufciency
411
coarctation involves aortic intimal thickening and
hyperplasia that obstructs the aortic lumen.
Patients who do not receive repair can manifest
systemic hypertension, coronary artery disease,
stroke, aortic dissection, and heart failure. It is
also a risk factor for endocarditis.
Typical echocardiography targets include
evaluation of left ventricular function, as well as
a detailed arch examination performed with
high parasternal or suprasternal views to identify the coarctation. The coarctation appears in
the proximal descending thoracic arch and is
412
Fig. 33.10 Color
Doppler M-Mode
through the valve
demonstrating AI during
diastole
Fig. 33.11 Parasternal
short axis view at the
aortic valve level of a
16-year-old male
demonstrating
monocusp aortic valve,
notice circular crosssection of annulus in
systole
E. Su and S. Flores
identied with 2D imaging and color Doppler. A
stenosis pattern can be seen in aortic ow proximal to the coarctation where the peak ow
increases between the area proximal (Fig.33.12)
to and the area distal (Fig.33.13) to the coarctation. In the area proximal to the coarctation,
ow in systole extends into the diastolic phase
of the cardiac cycle whereas it is dampened in
diastole distal to the coarctation. In the older
unrepaired patient, collateralization around the
coarctation can diminish coarctation gradients
and magnitude of ndings though heart failure
is still a risk.
Features that need to be recognized include
evidence of global or regional left ventricular
dysfunction as well as the aortic Doppler features
mentioned above. They would likely be consistent with exam ndings of diminished lower
extremity pulses.
33 Adult Congenital Heart Disease
Fig. 33.12 Spectral
Doppler of transverse
aortic arch in a
17-year-old male with
untreated coarctation of
the aorta demonstrating
pronounced systolic
amplitude and
prolongation of ejection
into diastole
Fig. 33.13 Spectral
Doppler of descending
aorta in the same
17-year-old male as in
Fig.33.10 demonstrating
marked dampening of
systolic peak compared
to previous
413
Summary
Identication of congenital heart defects is heavily dependent on an excellent working knowledge of normal cardiac anatomy and function, as
well as advanced qualitative and quantitative
skills in echocardiography. As POCUS becomes
increasingly used in initial hemodynamic assessment, some recognition of congenital abnormalities and their physiological sequelae is likely
appropriate for optimal evaluation and management of critically ill patients.
414
E. Su and S. Flores
References
1. Wiyono SA, Witsenburg M, de Jaegere PP, RoosHesselink JW.Patent ductus arteriosus in adults: case
report and review illustrating the spectrum of the
disease. Neth Heart J. 2008;16(7–8):255–9. https://
doi.org/10.1007/BF03086157. PMID: 18711613;
PMCID: PMC2516289
Further Reading
Mulder BJ. Epidemiology of adult congenital heart
disease: demographic variations worldwide. Neth
Heart J. 2012;20(12):505–8. https://doi.org/10.1007/
s12471- 012- 0335- 1. PMID: 23225563; PMCID:
PMC3515732
Gilboa SM, Devine OJ, Kucik JE, Oster ME, Riehle-
Colarusso T, Nembhard WN, Xu P, Correa A, Jenkins
K, Marelli AJ.Congenital heart defects in the United
States: estimating the magnitude of the affected population in 2010. Circulation. 2016;134(2):101–9. https://
doi.org/10.1161/CIRCULATIONAHA.115.019307.
Epub 2016 Jul 5. PMID: 27382105; PMCID:
PMC4942347
Part III
Ultrasonography
Eusion
NicholasA.Leverone andDanielA.Sweeney
34
Learning Objectives
1. Learn how to perform an ultrasound exam to
identify pleural uid in a critically ill patient
2. Learn methods to estimate pleural uid vol-
ume with bedside ultrasound
3. Recognize and interpret sonographic charac-
teristics of pleural uid
4. Understand how Point-of-care ultrasound
(POCUS) can inform pleural uid management decisions including whether to place a
chest tube; in the future, POCUS may prove
to be useful in identifying patients who would
be best served with video-assisted thoracoscopic surgery
Ultrasound Technique
forIdentifying Pleural Fluid
Patient andMachine Positioning
In the intensive care unit (ICU) bedside ultrasound examination for the identication and
treatment of pleural effusions should be performed with the patient in a supine or semirecumbent position (Fig. 34.1a). Machine
N. A. Leverone · D. A. Sweeney (*)
Division of Pulmonary, Critical Care, Sleep Medicine
and Physiology, Department of Medicine, University
of California, San Diego, La Jolla, CA, USA
e-mail: nleverone@health.ucsd.edu
placement is variable. Some experts advocate
having both the examiner and ultrasound machine
on the patient’s right side so that the examiner is
holding the probe in their dominant right hand
and manipulating ultrasound buttons with their
left hand. Alternatively, if the examiner stands on
one side of the patient and places the machine on
the opposite side of the patient then the patient
and the machine are in the same line of sight,
similar to how an interventional cardiologist performs a cardiac catheterization. While this position makes live imaging more intuitive to interpret
and is optimal for ultrasound guided procedures,
it does require either using two operators or the
examiner must reach across the patient to manipulate ultrasound controls.
Scanning Technique
A low frequency (2–5MHz) phased array probe
(cardiac or abdominal preset) is used as this provides adequate penetration and the small footprint allows for the probe to be positioned in
between ribs. The probe should be held in the
horizontal orientation in the palm of the hand that
is resting on the patient’s bed (Fig. 34.1b).
Scanning is performed along the posterior axillary line as free-owing dependent uid will settle in the posterior chest of a supine patient. After
rst identifying the liver (right side) or the spleen
(left side), the probe is moved cephalad from one
© The Author(s), under exclusive license to Springer Nature Switzerland AG 2025
M. J. Lanspa, A. T. Levinson (eds.), Echocardiography and Ultrasonography in the ICU,
Respiratory Medicine, https://doi.org/10.1007/978-3-031-80038-2_34
417
418
N. A. Leverone and D. A. Sweeney
Fig. 34.1 Examiner,
patient, and ultrasound
machine can be
positioned all along the
same visual axis to
prevent forcing the
examiner to have to
twist and turn during
examination or
procedure (a). When
holding the ultrasound
probe to obtain initial
imaging and orientation,
the probe marker should
be aimed cephalad,
along the posterior
axillary line sliding
superiorly or inferiorly
to identify the
diaphragm (b). Here you
can see the dorsal aspect
of the hand resting
against the bed to
achieve alignment with
the posterior axillary
line in the supine
patient. Courtesy of
Catherine Cichon, MD
a
b
intercostal space to another along the posterior
axillary line. Within each intercostal space, the
probe should be fanned anteriorly to posteriorly
to fully interrogate the space.
In the absence of a pleural effusion, lung con-
solidation, or atelectasis at the base of the lung, the
structures visualized by POCUS include: the chest
wall, the dome of diaphragm, and the spine with
spine shadow posterior to the liver or the spleen
(Fig.34.2). If the spine and spine shadow (referred
to as “the spine sign”) are imaged cephalad to the
diaphragm, this necessarily means that pathology
34 Eusion
Fig. 34.2 Landmarks in
the presence (a) and
absence (b) of pleural
effusion demonstrating
visualization of spine
sign in the presence of
intrathoracic pathology.
Consolidated lung and
uid both allow
transmission of
ultrasound waves,
permitting visualization
of deeper structures
normally impossible to
see through aerated lung
tissue
419
a
b
is present in the chest cavity. This is because normally ultrasound waves do not transmit through
aerated lung, preventing visualization of the
underlying spine. The spine sign occurs when
consolidation, atelectatic lung, pleural effusion, or
some combination of these is present making it
possible to visualize the vertebral column through
the thoracic cavity. When a pleural effusion is
present, then both the uid and accompanying
“drowned” lung will be visible via POCUS.In the
event that the ultrasound image is saved, radiology
convention dictates that the image be orientated
such that the left side of the image is cephalad and
the right side is caudad; if for some reason the
saved image violates this convention, then simply
label the picture accordingly.
420
N. A. Leverone and D. A. Sweeney
Quantication ofPleural Fluid
Volume Using Ultrasound
The volume of a pleural effusion has implications
for clinical management in critical care. Studies
have shown that the drainage of effusions greater
than 500mL result in signicant improvement in
patient oxygenation and respiratory mechanics,
including lung compliance and end expiratory
lung volume, although these benets are likely
reduced in patients with acute respiratory distress
syndrome (ARDS) [1–5]. While there is no
agreed upon method of using POCUS to estimate
the volume of a pleural effusion in a critically ill,
supine patient, a handful of approaches have been
proposed [4, 6, 7]. In general, these investigators
have derived formulas for estimating the volume
of the effusion based upon the maximal interpleural distance separating the surface of the
drowned lung and the chest wall, using a
transverse/axial image (i.e., probe placed along
posterior axillary line and oriented perpendicular
to the axis of the patient similar to a chest CT
image) (Fig.34.3). In one study by Balik et al, the
maximal distance (“Sep”) separating drowned
lung (at the lung base) from the chest wall was
measured at the end of expiration in 81 mechanically ventilated patients, who subsequently
underwent thoracentesis with complete drainage
of their pleural effusions. The authors derived a
formula to estimate the pleural effusion volume:
Volume (mL)=20×Sep(mm) showing a positive
correlation between Sep and effusion volume
(R =0.72, R
2
=0.52; P< 0.001)) [6]. Thus, a
Sep≥25mm would suggest an effusion volume
of at least 500mL.In clinical practice, however,
qualitative volume assessment (i.e., small,
medium, or large) of the pleural effusion with
ultrasound is more commonly used.
Characterization ofPleural Fluid
Based onUltrasound Imaging
Pleural uid ultrasound characteristics are
described along a spectrum ranging from
anechoic (black uid), complex nonseptated
(echogenic debris heterogenously present but
without loculations), complex septated (loculations present) to complex homogeneously echogenic uid pattern (echogenic material with
brightness approaching that of soft tissue)
(Fig.34.4) [8–10].
Transudative Versus Exudative Fluid
Bedside ultrasound image characteristics of pleural uid cannot always predict whether an effusion is a transudate or exudate. Across studies,
complex homogeneous echogenic effusions are
uniformly exudative and the presence of septated
uid is highly predictive for exudative uid (positive predictive value of ≥89%) [8–11].
Unfortunately, the appearance of anechoic or
complex nonseptated uid is not reliably informative in terms of whether a pleural collection is
transudative or exudative. Traditionally, anechoic
uid was thought to be highly suggestive of a
transudate; however, more recent studies do not
support this nding [10]. Furthermore, differences in gain and other control settings chosen by
the operator, as well as advances in ultrasound
image quality have made it challenging to uniformly discern between anechoic and complex
nonseptated uid. Measuring pixel intensity of
pleural uid ultrasound images is another possible tool for differentiating transudative versus
exudative effusions [12, 13]. However, this technology is not yet widely available on commercial
ultrasound machines.
Malignant Fluid
While it has been suggested that a swirling pattern of complex nonseptated uid pleural uid is
suggestive of a malignant effusion in patients
with an underlying diagnosis of cancer, others
have identied this nding in both patients with
exudative (nonmalignant) and transudative effusions [14, 15]. Instead of the ultrasound character
of the uid, more telling signs suggestive of a
malignant effusion involve the pleura and include
pleural thickening >1cm, pleural nodularity, and
diaphragmatic thickening >7mm [16].
Empyema
One of the most important and time sensitive
questions to answer, following identication of