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recommendations difficult. Furthermore, chronic immunosuppression remains a cofactor for recurrence
and subsequent hernia repairs, thus adding to the complexity of hernia repair in this population.

Patient comorbidities
Preoperative patient factors that predispose to incisional hernia in transplant patients include male gender,
advanced age (studies cite ages greater than 45-60 as risk factors), elevated BMI (BMI > 25), smoking,
malnutrition (serum albumin levels less than 3.5 g/L), connective tissue disorders (e.g., osteogenesis
imperfecta, certain subtypes of Ehlers-Danlos syndrome, and Marfan syndrome), immediately preoperative
chemotherapy and/or radiation to the operative site or region, presence of large volume ascites, COPD,
[2-6]
previous surgery in the operative area, anemia, steroid use, diabetes mellitus, and immunosuppression .
Furthermore, patients with end-stage renal or liver disease live in catabolic states in which muscle atrophies
and the abdominal wall weakens.

Postoperative factors associated with incisional hernia include wound infection, pulmonary complications,
prolonged ICU stay, severe ascites, anemia, thrombocytopenia, acute rejection with steroid treatment, and
[2-6]
same-site repeat surgery with fascial reopening and reclosure .
Common to these risk factors - obesity, ascites, and COPD - is increased intra-abdominal pressure, which
puts mechanical stress on the fascial closure and weakens the abdominal wall, making patients more
[2,4]
prone to wound necrosis, breakdown, and hernia . Furthermore, medical issues such as benign prostatic
hypertrophy chronic constipation, and chronic cough can also significantly increase intra-abdominal
pressure and thus jeopardize the integrity of hernia repairs. Lower abdominal incisions are also more
prone to hernia, as increased abdominal pressure is greater in the dependent abdomen and a pannus may
put tension on healing fascia. A patient undergoing abdominal organ transplant should be optimized to
the greatest extent possible in the preoperative period. This should include careful medical management
of weight, pulmonary function, and ascites to decrease postoperative intra-abdominal pressure, thus
decreasing the incidence of developing incisional hernia. Unfortunately, patients often spend months
and years on a transplant list and are often not adequately optimized for surgery when an organ actually
becomes available.

Technique-related risk factors
Technique-related factors that increase risk for an incisional hernia after transplant include excess tension
[2-6]
upon fascial closure, emergency surgery, and type of incision . A surgeon’s choice of incision for solid
organ transplant surgery depends on the type of organ transplanted, surgeon preference, and patient-
specific factors such as previous surgeries and organ size. The larger incisions with liver transplants are, in
part, why liver transplant patients have a much higher incidence of hernia compared to renal transplant
patients. Incisions commonly used in liver transplants include bilateral subcostal, Mercedes, and upper
midline incisions, among multiple other variants [Figure 1]. Bilateral subcostal and Mercedes incisions are
the most commonly used, as they provide excellent exposure. However, these large incisions with hours
of stout retraction can lead to greater areas of fascial weakening, thus increased risk of future hernia. The
Mercedes incision carries an increased risk of incisional hernia when compared to bilateral subcostal
[2]
incisions . The triple point of the Mercedes incision is a common area of decreased perfusion and
increased tension, which can lead to wound ischemia, necrosis, and dehiscence at the levels of the fascia
and/or the skin. Few studies exist regarding optimal closures for liver transplant incisions to prevent hernia.
[7]
In a retrospective study from 2010, Aydin et al. described a unique approach for closure of abdominal
fascia in Mercedes incisions, designed to reinforce the triple point. In this technique, the transverse
components of the incision are closed in two overlapping layers, and the vertical component is closed in
one layer using a single suture that overlaps the medial corners of the transverse incisions before running
cephalad to the xiphoid. Patients whose fascia was closed in this method had significantly lower rates of