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Lateral edges of
rectus muscles
released from
external oblique
aponeurosis
Rectus muscle
Chapter 13 • Tissue and Fascial Expansion of the Abdominal Wall 241
Costal margin
Fascial attachments
of Gore-Tex removed
Figure 13-10.
Last piece of
Gore-Tex removed
Separation of parts
Rectus muscle
Biologic mesh overlay
reinforcement
Mesh underlay
reinforcement
(indicated by white
dash outline)
Closed
midline
incision
Figure 13-11.
Drains
242 Section V • Other Abdominal Wall Procedures
6. Pearls/Pitfalls
1. Assessing the Rapidity of the Fascial Expansion
This is a very difficult and laborious series of operations to perform. It is almost always on a
patient who has lost all hope of repair. The most important advice is to be slow and methodic. Do
not rush the Gore-Tex excision and prepare the patient for the extreme nature of the approach.
The surgeries have a high complication rate and a high risk of infection, seroma, skin necrosis,
and recurrent hernia. Unless the situation is acute, I prefer using tissue expansion to facilitate
skin closure as opposed to performing simultaneous Gore-Tex excision with VAC closure of the
skin.
The patient usually tolerates the smaller serial removal of Gore-Tex procedures well. I do recommend that the patient be extubated deeply (if possible), so as to limit coughing and bucking
as the patient wakes up. The Gore-Tex can rip with heavy pressure and the previous gains are
quickly lost.
2. Preventing Skin Necrosis in the Final Abdominal Wall Closure
The separation-of-parts procedure can result in skin necrosis if the skin and subcutaneous tissue
are elevated completely off of the fascia beyond the lateral edge of the rectus muscles. Perforators to the skin cluster around the umbilicus but extend along the entire length of the rectus
muscles. There are medial and lateral row perforators. Not all need to be preserved. I try to
preserve two to three lateral row perforators on each side. This is done by identifying one and
using a Kelly clamp to dissect it free with a large cuff of subcutaneous tissue. The other perforators will be in roughly the same line as the first one. Even one perforator can make a huge
difference and prevent skin flap necrosis. This is important, especially in the case of a tight skin
closure. Exposure of the midline closure and mesh can seriously compromise all of the previous
efforts.
Selected References
Argenta LC, Austad ED: Principles and techniques of tissue expansion. In McCarthy JG, editor: Plastic Surgery, 1990, W.B. Saunders Co,
pp 475–507.
Carlson GW, Elwood E, Losken A, Galloway JR: The role of tissue expansion in abdominal wall reconstruction, Ann Plas Surg 44:147,
2000.
Hobar PC, Rohrich RJ, Byrd S: Abdominal wall reconstruction with expanded musculofascial tissue in a posttraumatic defect, Plas Recon
Surg 94(2):379–383, 1994.
Jacobsen WW, Petty PM, Bite U, Johnson C: Massive abdominal-wall hernia reconstruction with expanded external/internal oblique and
transversalis musculofascia, Plas Recon Surg 100(2):326–335, 1997.
Lipman J, Medalie DA, Rosen MJ: Staged repair of massive incisional hernias with loss of abdominal domain: a novel approach, Am J Surg
195(1):84–88, 2008.
Mander EK: Reconstruction using soft tissue expansion. In Cohen M, editor: Mastery of plastic and reconstructive surgery, ed1, 1994, Little,
Brown and Co, pp 201–215.
Paletta CE, Huang DB, Dehghan K, Kelly C: The use of tissue expanders in staged abdominal wall reconstruction, Ann Plas Surg 42:259,
1999.
Chapter 13 • Tissue and Fascial Expansion of the Abdominal Wall 243
A
C
Figure 13-12.
B
D
C HAPT E R
14
Progressive Preoperative
Pneumoperitoneum for
Hernias with Loss of
Abdominal Domain
Alfredo M. Carbonell, DO, FACS, FACOS
1. Clinical Anatomy
1. Features/Characteristics of the Defect
s
Definition of Loss of Abdominal Domain
s
2. Measuring Loss of Domain
s
s
s
244
There is no consensus in the literature on the definition of loss of abdominal domain.
Determination of this condition is subjective and typically refers to massive hernias with
a significant amount of intestinal contents that have herniated through the abdominal
wall into a hernia sac that forms a secondary abdominal cavity. On physical exam, the
inability to reduce the herniated contents below the level of the fascia when the patient is
lying supine should raise suspicion of the diagnosis. Although the surgeon can often make
the assumption that a patient has loss of domain on physical exam, we utilize computed
tomography (CT) to determine the true nature of the hernia.
We define a loss of abdominal domain on CT scan as greater than 50% of the intestinal
contents lying outside the native abdominal cavity in the hernia sac. This may be more
accurately defined when the ratio of the volume of the hernia sac to the volume of the
abdominal cavity is ≥0.5.
A sagittal reconstruction of the CT scan is used to measure the length of the hernia sac from
the top to the bottom of the sac. The length of the abdominal cavity is measured from the
top of the diaphragm to the inferior aspect of the symphysis pubis (Fig. 14-1, A).
Axial reconstructions are used to measure the width of the hernia sac and abdominal cav-
ity at their widest point. The height of the hernia sac is measured from an imaginary line
drawn across the hernial orifice to the apex of the hernia sac at its tallest portion. The
height of the abdominal cavity is measured from the anterior portion of the fourth lumbar
space to an imaginary line drawn across the hernial orifice (see Fig. 14-1, B).
Chapter 14 • Progressive Preoperative Pneumoperitoneum 245
Hernial
orifice
A
Figure 14-1.
Hernial
orifice
B
246 Section V • Other Abdominal Wall Procedures
s
s
Physiology of Hernias with Loss of Abdominal Domain
s
4. Physiology of Progressive Preoperative Pneumoperitoneum
Using the formula to measure the volume of an ellipsoid (V = 4/3 × π × r1 × r2 × r3),
the hernia sac and abdominal cavity volumes can be measured and compared. To simplify
the ellipsoid volume equation, multiply the length, height, and width measurements of the
cavities times a factor of 0.52 (V = 0.52 × L × H × W). Loss of domain exists when the ratio
of the volume of the hernia sac to the volume of the abdominal cavity is ≥0.5.
In patients with loss of abdominal domain, the bowels reside outside the abdominal cav-
ity. As intraabdominal pressure decreases to approach atmospheric pressure, abdominal
viscera become edematous and their vasculature becomes engorged. This makes simple
hernia reduction nearly impossible. In addition, respiratory function is altered secondary
to the loss of diaphragmatic support, and anterior spinal support fails, leading to lordosis.
s
The immediate reintroduction of viscera and abdominal reconstruction in patients with
loss of domain can result in a significant increase in intraabdominal pressure, which can
lead to abdominal compartment syndrome and its resultant ill effects. Progressive preoperative pneumoperitoneum (PPP) attenuates the adverse physiologic effects associated
with ventral hernia repair in patients with a loss of abdominal domain.
s
Insufflation of the abdominal cavity acts as an intraperitoneal pneumatic tissue expander
and lengthens the abdominal wall musculature, increasing the volume of the abdominal
cavity. This allows for adequate accommodation for the herniated contents.
s
The pneumoperitoneum also dissects throughout the intraperitoneal cavity providing a
pneumatic lysis of adhesions aided by gravity as the bowels are suspended by their adhesions within the hernia sac.
s
Physiologically, PPP slowly creates a chronic abdominal compartment syndrome. With
decreased diaphragmatic excursion, the patient is forced to overcome the inherent
decreased inspiratory capacity. Additionally the adverse cardiovascular effects of acute
abdominal compartment syndrome are attenuated by the slow introduction of intraperitoneal air.
2. Preoperative Considerations
1. Physical Examination
s
The physical exam alone is often helpful in determining whether a patient has loss of
domain. With the patient lying supine on the examination table, the surgeon should
attempt to reduce the herniated contents below the fascia. If the hernia does not reduce
because of the amount of herniated contents, the patient likely has loss of domain
Chapter 14 • Progressive Preoperative Pneumoperitoneum 247
s
s
s
2. Computed Axial Tomography
s
s
s
s
s
The abdominal wall should be examined for elasticity. Although some massive hernias may
be irreducible, the patient’s abdominal wall musculature may have such laxity and elasticity that it could accommodate the herniated contents easily at the time of surgery. This
finding would obviate the need for PPP because single stage repair may be feasible.
The quality of the skin should be examined to determine if any adjunctive maneuvers will
be required to obtain safe skin closure at the time of hernia repair.
Wide thin scars, ulcerated skin, thin subcutaneous tissue with tense and immobile skin,
and large pannus flaps should all raise concern over skin closure. Consultation with a
plastic surgeon may help determine the need for preoperative tissue expanders, panniculectomy, or complex skin closure at the time of hernia repair.
As previously described, the volume of the hernia sac and abdominal cavity are calculated
and compared. A volume ratio of the hernia sac to the abdominal cavity of ≥0.5 should
raise the suspicion of loss of abdominal domain.
Other attributes of the abdominal wall should be examined on CT because they may deter-
mine the utility or futility of preoperative pneumoperitoneum.
In our experience, patients with small defects and a significant amount of herniated con-
tents benefit the most from preoperative pneumoperitoneum.
Patients with round-shaped abdominal cavities and thick, robust rectus abdominis and
oblique muscles may experience less muscle lengthening with preoperative pneumoperitoneum compared to those with a more ellipsoid appearance to the abdominal wall and thin
atrophic musculature.
Patients with “open book” abdomens, such as those with significant loss of abdominal wall
substance (missing abdominal wall musculature) and hernia defects that span the entire
abdominal wall, may not benefit anatomically from preoperative pneumoperitoneum
because there may not be enough abdominal wall musculature to stretch. The physiologic
benefits may still be realized however.
3. Planning Abdominal Wall Reconstruction
s
Weight Loss
s
s
s
Most patients with massive hernias and loss of domain are obese. Every effort should be
made to have the patient lose weight preoperatively.
There is no standard rule, however, a weight loss of 20 to 30 pounds can make a large dif-
ference in the ability to obtain fascial closure and complete abdominal wall reconstruction
Our patients undergo a 4 to 8 week preoperative physician-observed meal replacement
program, which consistently achieves our target weight loss goal.
248 Section V • Other Abdominal Wall Procedures
s
Contaminated Abdominal Wall
s
s
3. Operative Steps
1. Stage I
s
Placement of Percutaneous Vena Cava Filter
s
s
s
s
Patients with enteral or urinary stomas or enterocutaneous fistulas are candidates for
PPP. Attention should be paid to the stoma to ensure ischemia does not develop during
insufflation.
Patients with infected mesh and massive hernia with loss of domain pose a special prob-
lem. Although still candidates for preoperative pneumoperitoneum, serious consideration
should be given to mesh removal and skin closure first followed by PPP at a second stage.
An abdominal wall with infected mesh will be indurated and edematous; as a result, little
muscle lengthening will occur with PPP. Additionally, mesh removal will undoubtedly
damage some abdominal wall, making the immediate reconstruction all the more difficult.
PPP significantly elevates the intraabdominal pressure and creates a chronic abdominal
compartment syndrome. As a result, venous return through the vena cava is decreased,
and patients are at risk for thromboembolic events.
Percutaneous vena cava filters protect patients from life-threatening pulmonary emboli.
They do not, however, prevent deep venous thrombosis.
We place patients on thrombotic chemoprophylaxis with heparin sodium.
Despite these aggressive measures, we have still had patients develop significant deep
venous thrombosis and near caval occlusion. Full-dose anticoagulation may be indicated
in patients who are more at risk.
s
Exploratory Laparoscopy with Placement of Percutaneous Catheter System
s
s
s
Exploratory laparoscopy allows for minimally invasive access to the abdominal cavity for
direct visualization and placement of a percutaneously placed intraperitoneal catheter sys-
tem for the pneumoperitoneum.
We use a 5-mm optical viewing trocar placed at the lateral hypochondrium (Fig. 14-2).
A peritoneal dialysis catheter is placed under direct vision, using the Seldinger technique
with a percutaneous, tear-away introducer sheath (Fig. 14-3).
Figure 14-2.
Chapter 14 • Progressive Preoperative Pneumoperitoneum 249
A
B
Figure 14-3.
250 Section V • Other Abdominal Wall Procedures
s
s
s
Patient Care Plan
s
s
s
s
2. Stage II
The catheter cuff is placed into the subcutaneous tissue and the catheter is sutured in posi-
tion (Fig. 14-4).
The pneumoperitoneum is evacuated, and the trocar site incision is closed with an absorb-
able subcuticular suture.
The patient is admitted to a step-down unit for close monitoring of pulse oximetry and all
vital signs
Chemothromboprophylaxis is begun postoperatively.
A full liquid diet with protein supplementation is started immediately.
The patient is instructed to utilize incentive spirometry and ambulate daily.
s
Progressive Preoperative Pneumoperitoneum
s
s
s
s
s
s
Peritoneal insufflation begins on the first postoperative day, and is performed daily.
Laparoscopic insufflation tubing is utilized to connect the air hose at the patient’s bedside
to the peritoneal dialysis catheter (Fig. 14-5).
The air is turned on slowly to begin insufflation. The patient is closely monitored for signs
of distress.
The insufflation proceeds and the patient will begin to complain of abdominal tightness
followed by mild flank discomfort. Once the patient begins to experience some shortness
of breath or mild anxiety, the insufflation is stopped. There is no specific volume of air that
should be injected nor the intraperitoneal pressure measured. The endpoint of insufflation
is always the patient’s level of discomfort.
The skin should be moisturized daily as pneumoperitoneum can lead to skin dryness and
cracking.
If at any point during this process the patient becomes hemodynamically unstable or
develops decreased urine output the pneumoperitoneum can be evacuated by wall suction
aspiration.