Open Journal of Radiology, 2013, 3, 130-132
http://dx.doi.org/10.4236/ojrad.2013.33021 Published Online September 2013 (http://www.scirp.org/journal/ojrad)
Right Hemisphere Cerebr al Infarction Due to Air
Embolism from Percutaneous Lung Biopsy: A Case Report
Chaitanya Ahuja1*, Yama Kharoti1, Jeffery J. Critchfield2, Meghna Chadha2
1Dotter Institute, Oregon Health & Science University, Portland, USA
2Wayne State University, Detroit, USA
Received April 18, 2013; revised May 18, 2013; accepted May 25, 2013
Copyright © 2013 Chaitanya Ahuja et al. This is an open access article distributed under the Creative Commons Attribution License,
which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
ABSTRACT
Percutaneous transthoracic needle biopsy is a common procedure in interventional radiology. Systemic arterial air em-
bolism causing cerebral infarction is a rare but much feared complication of percutaneous lung biopsy. We present a
comprehensive review of iatrogenic air embolism post-lung biopsy, a complication that is often sub optimally managed.
Patho-physiology, clinical features, and risk factors and management are reviewed.
Keywords: Air Embolism; Lung Biopsy; Cerebral Infarction; Computed Tomography (CT) Guidance
1. Introduction
A CT-guided need le lung biopsy is a common interven e-
tional radiology procedure. Percutaneous lung biopsy is
considered as a safe and effective method for obtaining a
tissue diagnosis in patients with lung masses. Reported
complications include pneumothorax, intrapulmonary he-
morrhage, hemoptysis, air embolism, seeding of the bi-
opsy tract, and death. The most common complication,
pneumothorax, is easily treated by radiologists and is
typically associated with no long-term sequela. Air em-
bolism as a complication is extremely rare; however it
can become fatal when it happens. Early diagnosis and
rapid application of hyperbaric oxygen therapy are the
mainstay of treatment.
2. Case Summary
An elderly gentleman with a known esophag eal mass and
multiple pulmonary nodules was referred for a CT
guided FNA biopsy of a pulmonary nodule. The patient
was placed in left lateral decubitus position on the CT
table. A 19 gauge needle was advanced under CT fluo-
roscopy into a righ t pulmonary nodule and FNA samples
were obtained in end inspiration (Figure 1). During the
procedure the patient became verbally unresponsive and
rapidly developed left sided hemiplegia. Subsequently, a
partial seizure was witnessed on the CT table. The pro-
cedure was concluded and a non contrast head CT was
obtained (Figure 2). The head CT showed gas within the
right MCA (Middle Cerebral Artery) territory vessels.
Hyperbaric oxygen therapy was initiated as per the insti-
tutional air embolism protocol. A subsequent brain MR
showed T2/FLAIR hyperintensity in the right MCA ter-
ritory along with diffusion restriction, compatible with
cerebral infarction (Figure 3). The patient developed
permanent disability as a result.
3. Discussion
Percutaneous lung biopsy is one of the most common
procedures performed in radiology departments. It is the
minimally invasive gold standard for the histopathologic
investigation of lung masses. Compared with other per-
cutaneous biopsy procedures, lung biopsy carries a higher
risk of potential complications, including occasional re-
ports of death. Very few case reports have been de-
scribed in literature relating to cerebral infarction due to
air embolism from percutaneous lung biopsy. The largest
series of four cases has been reported from Korea [1].
Though rare, air embolization from percutaneous lung
biopsy is a known and potentially devastating complica-
tion. Indeed, the few cases of death reported from this
procedure are most often due to air embolism. It can
cause subsequent myocardial infarction, intractable ar-
rhythmia or stroke [2]. The primary mechanism for in-
troduction of air embolism is the creation of an air-
way-pulmonary vessel fistula during the procedure [3].
Issues with technique, such as allowing the needle hub to
*Corresponding author.
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opyright © 2013 SciRes. OJRad

C. AHUJA ET AL. 131
Figure 1. CT fluoroscopy image showing a percutaneous
lung biopsy.
(a)
(b)
(c)
Figure 2. Non-contrast axial head CT images at three dif-
ferent levels showing serpiginous air within the right MCA
territory distribution.
be open to outside air, can also result in air emboli.
There are three vessels that can receive air emboli
during a lung biopsy. Air can enter a branch of the pul-
monary arteries and lodge in the pulmonary capillary bed.
While this can interfere with gas exchange and decrease
pulmonary function locally, the lungs are well equipped
to handle such situ ation s v ia hyp oxic v aso cons triction [4 ].
Air emboli in a bronchial artery will also lodge in the
(a)
(b)
Figure 3. (a) Axial MR FLAIR image shows diffuse right
middle cerebral artery territory edema. (b) Diffusion
weighted image at the same level demonstrates increased
diffusion restriction in the same region, compatible with
cerebral infarction.
pulmonary capillary bed and have a similar net result.
However, the more dreaded result is air entering a pul-
monary vein, which flows into the left atrium and is
therefore a conduit to the systemic circulation.
Once in the systemic circulation, an air embolus can
lodge in any distal vessel. Emboli to either the coronary
or cerebral arteries tend to result in the most profound
morbidity [3,5]. In the case of the cerebral vasculature,
there is a predilection for emboli to lodge in the right
cerebral hemisphere [1]. Conventional aortic arch anat-
omy has the brachiocephalic artery as the first major
branch of the aorta. It is also the largest of the three
branches arising from the aortic arch. Further, the bra-
chiocephalic artery is normally in a straight line with the
trajectory of the ascending aorta. Air emboli therefore
tend to select this vessel due to both its caliber and tra-
jectory. Air then travels in a straight line through the
right common carotid and right internal carotid arteries,
ultimately lodging in the cerebral vasculature.
To prevent this catastrophic complication, multiple
strategies for decreasing the incidence of air emboli have
been discussed. Performing CT guided lung biopsies in
suspended expiration, as opposed to end inspiration, will
result in a higher intrathoracic pressure, which will de-
crease the likelihood of air emoblization. Higher gauge

C. AHUJA ET AL. 132
needles may also be used. In particular, FNA can be ef-
fectively done with a 21 or 22-gauge needle and will be
less likely to induce air embolism than a 19-gauge or
larger needle. Though diseased lung is often the target of
a biopsy, the more diseased lung a needle is passed
through, the greater the probability of inducing an air
embolism is [6].
Vigilance for air embolism during lung biopsy can
help decrease the most devastating complications, in-
cluding stroke and death. Recognition of air within the
left atrium, left ventricle or aorta is critical. Quickly
placing the patient in Trendelenburg’s position with their
right side down will keep the air from embolizing distally.
Interventional Radiology may then aspirate the air with
an intravascular catheter. In the event of distal air embo-
lism, hyperbaric oxygen therapy is the mainstay of ther-
apy [7].
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