Keywords
hernia - abdominal compartment syndrome - pneumatic adhesiolysis
Introduction
Reduction of large abdominal hernias at a single operative sitting, can lead to sudden
rise of intra-abdominal pressure leading to abdominal compartment syndrome, which
can lead to severe respiratory distress. Preoperative progressive pneumoperitoneum
(PPP) uses intermittent insufflation of gas to stretch the abdominal muscles to increase
abdominal capacity so that large amounts of viscera can be repositioned into the abdominal
cavity without significantly raising intra-abdominal pressure.
Case Report
A 61-year-old male presented with the complaint of left inguinoscrotal swelling for
12 years. Local examination revealed a large, globular, soft left inguinoscrotal swelling
of size approximately 35 × 20 cm. Expansile cough impulse was positive over the swelling.
Diagnosis of left direct giant inguinal hernia was made. In view of the large size
of the swelling and for surgical planning, a computed tomography (CT) scan was done,
which revealed an approximately 4.6 × 4.8 cm size defect in the left inguinal region
with herniation of sigmoid colon ([Fig. 1]). The volume of hernial sac and abdominal cavity were 4122 and 11,372 cm3, respectively ([Fig. 2]). Given the parameters, loss of domain was 36%. Given the loss of domain being > 20%,
there was a risk of abdominal compartment syndrome, if simple operative reduction
of hernial sac was done.
Fig. 1 Axial computed tomography (CT) images depict the giant left inguinal hernial sac
(red arrow, A) containing sigmoid bowel as its content (yellow arrow, B).
Fig. 2 (A) Coronal computed tomography (CT) image demonstrating the calculated volume of the
abdominal cavity (volume of interest [VOI]) measuring 11,372 cm3. (B) Sagittal reformatted image depicting the giant left inguinal hernial sac containing
sigmoid bowel as its content (yellow arrow). (C) Volume rendering technique (VRT) image depicting the giant left inguinal hernia
sac.
Botulinum toxin A (BTA) injection into the abdominal wall musculature was considered.
However, in view of the high cost of the procedure, it could not be done. So, PPP
was planned as a viable cost-effective adjunct. Under CT guidance, left anterolateral
peritoneal lining was punctured by a 22G needle and 100 mL air was injected to create
artificial pneumoperitoneum. Subsequently, under CT guidance, left anterolateral abdominal
wall was punctured and an 8F pigtail was inserted into this artificially created pneumoperitoneum
cavity by Seldinger's technique ([Fig. 3]). Total air injected was 400 to 500 mL. Patient vitals were stable. A graded pneumoperitoneum
was created with insufflation of approximately 800 mL air per day over the course
of next 15 days. Abdominal girth increased from 100 to 113 cm. Patient was posted
for surgery once he could not tolerate any more insufflation of air.
Fig. 3 Axial computed tomography (CT) abdomen images show: (A) puncture of the left anterolateral abdominal wall with 22G needle (red arrow), followed by insufflation of 100 mL air to create artificial pneumoperitoneum (yellow arrow), (B) puncture of this pocket of artificial pneumoperitoneum with a 18G needle (green arrow), and (C) maximum intensity projection (MIP) image depicting the subsequently deployed 8F
pigtail (orange arrow) through this 18G needle via Seldinger's technique.
Under general anesthesia, Lichtenstein open tension-free mesh hernioplasty was done.
Postoperative course was eventful.
Discussion
A large inguinal hernia, which extends below the mid-thigh level, in standing position,
constitutes a “giant” inguinal hernia.[1] In long-standing hernias, there is gradual retraction of lateral abdominal musculature,
relaxation of the diaphragm, which reduces effective intra-abdominal volume. The herniated
bowel and mesentery also become edematous from venous and lymphatic congestion, secondary
to compression at the level of the fibrotic hernial ring. The forced hernial sac reduction
in an unprepared abdomen can lead to abdominal compartment syndrome, as well as the
fascial closure will be under tension, leading to wound dehiscence and hernia recurrence.
PPP is indicated when it is not possible to perform hernia repair due to the size
of the hernia and the loss of domain. The most widely accepted definitions of hernias
with loss of domain are when the hernia sac contains more than 20% of the abdominal
contents.[2]
The basic principle is to gradually increase the abdominal compartment volume and
reestablish the right of domain for abdominal viscera. Advantages of this procedure
are that it allows a gradual and more physiological adaptation of the patient's abdominal
cavity for subsequent hernia reduction, and additionally performs pneumatic adhesiolysis,
which reduces the amount of dissection performed intraoperatively.[3] The median amount of insufflated air is 9.02 ± 2.7 L with a range of 3.6 to 19.5
L.[3]
The common complications are due to the local site puncture, which includes bowel
perforation, solid organ injury, and intraluminal placement of the needle. Other complications
include shoulder pain, gastroesophageal reflux, respiratory distress, subcutaneous
emphysema, and venous stasis leading to subsequent venous thrombosis. The rate of
complications with PPP (25.6%) is much higher, as compared with the alternative techniques
described subsequently.[3]
PPP is being used with various modifications, throughout the world, with positive
results, however, with limited uptake.[4] The most common technique used is the one which has been described in our case,
with the endpoint of graded air insufflation being patient discomfort.
The various alternative techniques to PPP described in the literature include BTA
injection, usage of tissue expanders, debulking surgery such as omentectomy and limited
bowel resection, abdominal wall component separation, and transverse relaxing incisions.
BTA is also a commonly performed preoperative technique. BTA is a neurotoxin that
works by blocking the release of acetylcholine. It leads to temporary muscle flaccid
paralysis leading to decreased abdominal wall tension and facilitating tension-free
abdominal wall closure. It is injected under ultrasound or CT guidance into the lateral
abdominal wall muscles complex (external oblique, internal oblique, and transversus
abdominis). Its maximum effects come after 2 to 4 weeks following injection; however,
effect can last up to 6 months.[5] It can be used either as an addition, or in place of the currently available techniques,
prior to surgical reduction.
The advantages of BTA as compared with PPP (and other alternative techniques) are
that it is least invasive and has a low side effect profile. It additionally can reduce
pain by inhibiting the release of substance P and calcitonin gene-related peptide
that are involved in inflammation.[6]
The disadvantages of BTA are that it can cause paralysis when incorrectly injected
into unintended structures and high cost of the medicine. Its use is also contraindicated
in patients with neuromuscular disorders such as myasthenia gravis. In our case, it
was not used in view of its cost and nonavailability as part of routine supply in
our institution. When compared with BTA injection, PPP is equally efficacious, while
being cost-effective especially in developing countries like India.
Postoperative complications such as surgical site infection (17.5%) and recurrence
(5.9%) are much lower, when compared with other loss of domain hernia surgeries, without
the use of these preoperative techniques,[3] with successful closure of the defect reported in 98.2% cases.[3]
Conclusion
Surgical repair of giant inguinal hernias requires adequate preoperative preparation
of the abdominal cavity. PPP is a relatively safe and easy technique, which increases
the volume of the abdominal cavity, thereby reducing the risk of abdominal compartment
syndrome, as well as additionally performing pneumatic adhesiolysis.
