Abdominal Wall and Hernias

What are the 9 layers of the abdominal wall?

• Skin, subcutaneous tissue, superficial fascia, external oblique muscle, internal oblique muscle, transversus abdominis muscle, transversalis fascia, preperitoneal adipose and areolar tissue, and peritoneum

What is the portion of the external oblique aponeurosis that extends from the anterior superior iliac spine to the pubic tubercle called?

• Inguinal (Poupart) ligament

What directions do the fibers of the external oblique course?

• Superolateral to inferomedial

What directions do the fibers of the internal oblique course?

• Inferolateral to superomedial

What directions do the fibers of the transversus abdominis course?

• Transverse

Where does the aponeurosis, which is originally divided into anterior and posterior lamella that envelops the rectus abdominis muscle, begin to course anteriorly to the rectus abdominis muscle and become part of the anterior rectus sheath?

• Semicircular line (of Douglas/arcuate line)

What are the borders of Hesselbach triangle?

• Inguinal ligament inferiorly, lateral margin of the rectus sheath medially, and inferior epigastric vessels laterally

What makes up the floor of Hesselbach triangle?

• Transversalis fascia

What structures course through the preperitoneal space?

• Inferior epigastric artery and vein; median umbilical ligament (urachus—remnant of fetal allantoic stalk); medial umbilical ligaments (vestiges of fetal umbilical arteries); falciform ligament

What are the 9 potential spaces of the abdomen?

• Right subphrenic; left subphrenic; right paracolic gutter; left paracolic gutter; subhepatic; supramesenteric; inframesenteric; lesser space; pelvis

What is the function of the peritoneum?

• To promote sequestration and removal of bacteria from the peritoneal cavity, control the amount of fluid in the peritoneal cavity, and facilitate the migration of inflammatory cells from the microcirculation into the peritoneal cavity

What is the most reliable method to help determine the cause of ascites?

• The serum-ascites albumin gradient (SAAG)

How do you calculate the SAAG?

• Serum albumin concentration – ascites albumin concentration

What does a SAAG <1.1 g/dL signify?

• Absence of portal hypertension (biliary ascites, nephrotic syndrome, pancreatic ascites, peritoneal carcinomatosis, post-op lymphatic leak, serositis with connective tissue disease, tuberculous peritonitis)

What does a SAAG >1.1 g/dL signify?

• Presence of portal hypertension (alcoholic hepatitis, Budd-Chiari syndrome, cardiac ascites, cirrhosis, fulminant liver failure, massive liver mets, myxedema, portal vein thrombosis)

How much albumin should be given for every liter of ascites removed after large volume paracentesis (>5 L)?

• 6 to 8 g of albumin/L of ascites removed

Most common malignancy associated with chylous ascites:

• Lymphoma

Term for bacterial infection of ascitic fluid in the absence of an intra-abdominal, surgically treatable source of infection:

• Spontaneous bacterial peritonitis

What is the management of spontaneous bacterial peritonitis?

• Third-generation cephalosporin (eg, ceftriaxone)

Treatment for tuberculous peritonitis:

• Antituberculous drugs (isoniazid and rifampin daily for 9 months commonly used)

Initial treatment for peritoneal dialysis–associated peritonitis:

• Intraperitoneal administration of antibiotics (usually first-generation cephalosporin)

Treatment for recurrent/persistent peritoneal dialysis-associated peritonitis:

• Removal of the dialysis catheter and resumption of hemodialysis

What disease entails a mucous-secreting tumor coating the peritoneum and filling the peritoneal cavity with mucus and large loculated cystic masses?

• Pseudomyxoma peritonei

Treatment for pseudomyxoma peritonei:

• Drainage of mucus and intraperitoneal fluid

• Peritonectomy and omentectomy with cytoreduction of primary and secondary tumor implants

• Right colectomy for appendiceal adenocarcinoma or total abdominal hysterectomy and bilateral salpingo-oophorectomy for ovarian carcinoma

• Post-op intraperitoneal chemo/mucolytics

Term for the dilated superficial paraumbilical veins in this seen with portal venous obstruction:

• Caput medusae

What nodal system do the supraumbilical lymphatic vessels drain?

• Axillary lymph nodes

What nodal system do the infraumbilical lymphatic vessels drain?

• Superficial inguinal lymph nodes

Where does visceral pain from inflammation of the stomach, duodenum, or biliary tract (foregut) localize?

• Epigastrium

Where does visceral pain from inflammation of the small intestine, appendix, or right colon (midgut) localize?

• Periumbilical region

Where does visceral pain from inflammation of the left colon and rectum (hindgut) localize?

• Hypogastrium

Why is visceral pain felt in the midline rather than lateralize?

• Organs transmit sympathetic sensory afferents to both sides of the spinal cord.

Where would you expect referred pain with irritation of the diaphragm?

• Shoulder pain

Where would you expect referred pain with acute biliary tract disease?

• Scapular pain

Where would you expect referred pain with retroperitoneal inflammation?

• Testicular or labial pain

Make the diagnosis: a newborn is noted to have passage of meconium and mucus from the umbilicus in the first few days of life:

• Patent omphalomesenteric duct

What is the treatment for a patent omphalomesenteric duct?

• Laparotomy with excision of the fistulous tract

How can an umbilical polyp (persistence of distal omphalomesenteric duct) be differentiated from an umbilical granuloma?

• Umbilical polyp will not disappear after silver nitrate cauterization; umbilical granuloma will disappear after silver nitrate cauterization

What is the treatment for a vesicocutaneous fistula (patent urachus)?

• Excision of the urachal remnant with closure of the bladder if needed

Term for a midline protrusion of the anterior abdominal wall secondary to thinning of the linea alba in the epigastrium with intact transversalis fascia:

• Diastasis recti

Treatment for diastasis recti:

• Reassurance

How is a rectus sheath hematoma usually managed?

• Rest and analgesics, correction of coagulopathy, and blood transfusion if necessary

How do you manage a rectus sheath hematoma that progresses despite nonoperative measures?

• Angiographic embolization of the bleeding vessel or operative evacuation of the hematoma and hemostasis (uncommon).

What is the treatment of an abdominal wall desmoid tumor?

• Complete resection with a tumor-free margin with or without adjuvant radiation; if deemed unresectable, it can be treated with radiation therapy alone or with antiproliferative agents and cytotoxic chemotherapy.

What are the 2 most widely used groups of noncytotoxic drugs used for the palliation of abdominal wall desmoid tumors?

• Antiestrogens (Tamoxifen) and nonsteroidal anti-inflammatory drugs (NSAIDs) (Sulindac)

What are clinical characteristics suggestive of an abdominal wall malignancy?

• Fixation to the abdominal wall, fixation to abdominal organs, recent increase in size, size >5 cm, and nonreducible lesion arising from below the superficial fascia

How is the definitive diagnosis of an abdominal wall sarcoma made?

• Core needle biopsy (choose this one on the test) or by incisional biopsy oriented in the same plane as the underlying muscle.

Treatment for an abdominal wall sarcoma:

• Resection with tumor-free margins with reconstruction accomplished primarily, with myocutaneous flaps, or with prosthetic meshes.

Treatment for an omental cyst:

• Local excision

Most common malignancy of the omentum:

• Metastases

The greater omentum derives its arterial blood supply from which arteries:

• Omental branches of the right and left gastroepiploic arteries

Make the diagnosis: a patient presents with acute right lower quadrant abdominal pain and is explored for suspected appendicitis and is subsequently found with enlarged mesenteric lymph nodes and a normal appendix:

• Acute mesenteric lymphadenitis

Infection with what organism is associated with acute mesenteric lymphadenitis in children?

• Yersinia enterocolitica

Term for a rare inflammatory disease of the mesentery characterized by fat necrosis, acute and chronic inflammation, and fibrosis:

• Mesenteric panniculitis

Treatment of mesenteric panniculitis:

• Usually resolves spontaneously; if it does not resolve, can try corticosteroids or other anti-inflammatory/immunosuppressive agents.

Term for a congenital hernia in which the small intestine herniates behind the mesocolon:

• Mesocolic (paraduodenal) hernia

Operative management for a patient with a right mesocolic (paraduodenal) hernia:

• Incise the lateral peritoneal reflections along the right colon with reflection of the right colon and cecum to the left without opening the hernia neck (could injure superior mesenteric vessels).

Operative management for a patient with a left mesocolic hernia:

• Incise the peritoneal attachments and adhesions along the right side of the inferior mesenteric vein; reduce herniated small intestine from beneath the inferior mesenteric vein; return inferior mesenteric vein to the left side of the base of the small bowel mesentery; close the neck of the hernia by suturing the peritoneum adjacent to the vein to the retroperitoneum.

Most common location for a mesenteric hernia:

• Near the ileocolic junction

Treatment for a mesenteric hernia:

• Reduce the hernia and close the mesenteric defect

Most common primary malignancy of the mesentery:

• Desmoid tumor

Treatment for desmoid tumor of the mesentery:

• Surgical resection versus watchful waiting with sulindac and antiestrogen therapy versus imatinib mesylate (Gleevec)

Treatment for a retroperitoneal abscess:

• Antibiotics and CT-guided drainage; if not amenable to percutaneous drainage or if fails to resolve with percutaneous drainage, then perform operative drainage through a retroperitoneal approach.

How do you make the diagnosis of retroperitoneal fibrosis?

• Patient's history and IV urography demonstrating medial deviation of the ureters and hydronephrosis and hydroureter associated with delayed excretion

Treatment for primary, idiopathic retroperitoneal fibrosis:

• Ureteral stenting and immunosuppression (methylprednisolone, azathioprine, penicillamine, tamoxifen)

Usual treatment for secondary cases of retroperitoneal fibrosis with compromised renal function:

• Midline transperitoneal ureterolysis with wrapping of the ureter with an omental flap versus lateral retroperitoneal ureteral transposition

Most common malignant retroperitoneal tumor:

• Lymphoma

Most common primary malignancy of the retroperitoneum:

• Sarcoma (liposarcoma)

Prognostic factors for retroperitoneal sarcoma:

• Histologic grade and tumor size

Treatment for retroperitoneal sarcoma:

• Complete en bloc resection of the tumor with any involved adjacent organs (primary treatment); if invading inferior vena cava (IVC), the IVC can be excised and bypassed in the absence of sufficient collaterals. There used to be no role for radiation secondary to visceral toxicity, but with the advent of better radiation some institutions are giving radiation either pre- or postoperatively. If inoperable, symptomatic disease can consider chemotherapy with radiation.

Type of hernia with an indirect and direct hernia component:

• Pantaloon hernia

Most common hernia:

• Indirect inguinal hernia

What is your differential diagnosis for a groin mass?

• Abscess, epidermal inclusion cyst, femoral artery aneurysm, hernia, hydrocele, hematoma, seroma, lymphadenopathy, sarcoma, testicular torsion, and undescended testicle

On what side do inguinal hernias usually occur?

• Right side (delay in atrophy of processus vaginalis after slower descent of right testis to scrotum during fetal development)

On what side do femoral hernias usually occur?

• Right side (possibly from tamponading effect of sigmoid colon on left femoral canal)

What type of hernia are most strangulated hernias?

• Indirect inguinal hernia

What ligament is formed by the periosteum and fascia along the superior pubic ramus?

• Cooper ligament

What attaches the testicle to the scrotum?

• The gubernaculum

Name the contents of the spermatic cord:

• Cremasteric muscle fibers, testicular artery, testicular pampiniform venous plexus, genital branch of the genitofemoral nerve, vas deferens, and processus vaginalis ± hernia sac

What are the boundaries of the inguinal canal?

• Anterior—external oblique aponeurosis

• Posterior—transversalis fascia and the aponeurosis of transversus abdominis

• Superior—internal oblique and transversus abdominis musculoaponeurosis

• Inferior—inguinal ligament and lacunar ligament

Where do direct inguinal hernias occur with regards to Hesselbach triangle?

• Direct hernias occur within Hesselbach triangle

Where do indirect inguinal hernias occur with regards to Hesselbach triangle?

• Indirect inguinal hernias occur lateral to Hesselbach triangle

What nerve runs anterior to the spermatic cord in the inguinal canal and branches at the superficial inguinal ring?

• Ilioinguinal nerve

What nerve innervates the skin on the lateral side of the scrotum and labia and the cremaster muscle?

• The genital branch of the genitofemoral nerve

Which nerves provide sensation to the base of the penis, skin of the groin, and ipsilateral upper medial thigh?

• The iliohypogastric and ilioinguinal nerves

What are the boundaries of the femoral canal?

• Superior—iliopubic tract

• Inferior—Cooper ligament

• Lateral—femoral vein

• Medial—junction of iliopubic tract and Cooper ligament (lacunar ligament)

What kind of femoral hernias need to be repaired?

• All femoral hernias need to be repaired (high incidence of strangulation)

What are the various methods through which a femoral hernia can be repaired?

• Cooper ligament repair, via a preperitoneal approach, or a laparoscopic approach

What are the essential steps of femoral hernia repair?

• Dissection and reduction of the hernia sac; obliteration of the femoral canal defect in the femoral canal by approximation of the iliopubic tract to Cooper ligament versus placement of prosthetic mesh.

What is the primary danger associated with a sliding hernia?

• Failure to recognize the visceral component of the hernia sac before injury to bowel/bladder

Most common organ found in a sliding hernia in a female patient:

• Ovaries/fallopian tubes

Most common organ found in a sliding hernia in a male patient:

• Cecum/sigmoid colon

Next step if you cannot reduce an incarcerated femoral hernia:

• Divide the inguinal or lacunar ligament

What should you do if during repair of an incarcerated inguinal hernia with a concern for strangulation you lose control of the hernia sac and the contents of the hernia drop back into the abdomen?

• Explore through preperitoneal incision by opening the peritoneum versus laparoscopy

What procedure do you perform to repair an inguinal hernia in infants and children?

• High ligation of the hernia sac

What is the percentage risk for hernia incarceration with watchful waiting?

• 0.03%

What does a cord lipoma represent?

• Retroperitoneal fat that has herniated through the deep inguinal ring

How many cm of mobilization can be obtained when component separation is applied to both sides of the abdominal wall?

• Up to 20 cm of mobilization

Term for the space that is first entered in an extraperitoneal hernia repair that lies between the posterior rectus sheath and pubic bone anteriorly and the vesicoumbilical fascia posteriorly:

• The space of Retzius

Which types of patients may benefit from a laparoscopic hernia repair?

• Patients with bilateral or recurrent inguinal hernias

What are relative contraindications to laparoscopic inguinal hernia repair?

• Nonreducible, incarcerated inguinal hernia; prior laparoscopic herniorrhaphy; massive scrotal hernia; prior pelvic lymph node resection; prior groin irradiation

What are absolute contraindications to laparoscopic inguinal hernia repair?

• Inability to tolerate general anesthesia

What are the borders of the Triangle of Doom?

• Vas deferens medially; spermatic vessels laterally; external iliac vessels inferiorly

What structures are contained within the Triangle of Doom?

• External iliac vessels, deep circumflex iliac vein, genital branch of genitofemoral nerve, femoral nerve

What are the borders for the Triangle of Pain?

• Spermatic vessels medially, iliopubic tract superolaterally

What structures are contained within the Triangle of Pain?

• Lateral femoral cutaneous nerve and anterior femoral cutaneous nerve of the thigh

Why is the Triangle of Pain significant?

• Placing tacks in this area may lead to chronic pain from injury to the lateral femoral cutaneous nerve/anterior femoral cutaneous nerve of the thigh.

What is the Circle of Death in regards to hernia repair?

• Also known as the corona mortis, a vascular ring formed by the joining of an aberrant artery with the normal obturator artery arising from a branch of the internal iliac artery; during a laparoscopic hernia repair this vessel can be torn from both ends and bleed profusely

What must you remember to do before leaving the operating room after repairing an inguinal hernia in a male patient?

• Pull the testicle back down into the scrotum

Most common early complication following hernia repair:

• Urinary retention

Overall complication rate from hernia repair:

• 10%

Risk for surgical-site infection with open hernia repair:

• Estimated to be 1% to 2%

Do you need to administer routine preoperative antibiotics to patients undergoing hernia repair?

• No, consider a clean operation

Which patients undergoing hernia repair might you consider giving preoperative antibiotics?

• Patients with significant underlying disease (ASA score >3)

If you have to give preoperative antibiotics before a hernia repair, what antibiotics do you give? How about a penicillin allergic patient?

• Cefazolin, 1 to 2 g IV 30 to 60 minutes before incision; if penicillin allergic, give clindamycin 600 mg IV or vancomycin 1 g IV

What nerves are most commonly affected during open hernia repair?

• Ilioinguinal, iliohypogastric, and genital branch of the genitofemoral nerve

What nerves are most commonly affected during laparoscopic hernia repair?

• Lateral femoral cutaneous and genitofemoral nerves

What is the usual best treatment for patients who present with a nerve entrapment syndrome after open inguinal hernia repair?

• Initial treatment should include a long trial of observation, NSAIDS, and possibly nerve blocks (exhaust every possible solution before taking the patient back; unless the patient is experiencing nerve entrapment immediately postoperatively in the PACU, in that case take them back). Repeat exploration with neurectomy and mesh removal as needed.

What is the pathogenesis of ischemic orchitis after inguinal hernia repair?

• Thrombosis of the small veins of the pampiniform plexus within the spermatic cord resulting in venous congestion of the testis with resultant progressive pain and swelling usually resulting in testicular atrophy (the most common cause is extensive dissection of a scrotal hernia sac).

Where does recurrence of an inguinal hernia usually occur?

• The floor of the inguinal canal near the pubic tubercle where the tension on the suture line is the greatest.

What is the rate of hernia recurrence?

• 1% to 3%

What is the time period that hernias usually recur?

• Usually within the first 2 years after repair

How would you repair an incisional hernia with a small defect (<2 cm in diameter) with viable surrounding tissue?

• Primary repair

When would you use a prosthetic mesh to repair an incisional hernia?

• Incisional hernia with a large defect (>2–3 cm diameter)

What is the minimal desired overlap of mesh around the defect when performing a laparoscopic ventral hernia repair?

• 4 cm

What kind of hernia occurs at sites where vessels and nerves perforate the linea alba?

• Epigastric hernia

What kind of hernia occurs between the rectus muscle medially and the semilunar line laterally?

• Spigelian hernia

Why is it recommended that spigelian hernias be repaired?

• The risk for incarceration associated with its relatively narrow neck.

What is Howship-Romberg sign?

• Obturator hernia causing pain along the medial aspect of the proximal thigh from nerve compression.

What are the borders of the superior lumbar (Grynfeltt) triangle?

• Medial—quadratus lumborum

• Lateral—internal abdominal oblique

• Superior—12th rib (floor—transversalis fascia; roof—external abdominal oblique)

What are the borders of the inferior lumbar (Petit) triangle?

• Medial—latissimus dorsi

• Lateral—external abdominal oblique

• Inferior—iliac crest (floor—internal abdominal oblique)

Which lumbar hernia is more common? Grynfeltt hernia or Petit hernia?

• Grynfeltt hernia

The most common symptom of a sciatic hernia:

• Presence of an uncomfortable or slowly enlarging mass in the gluteal or intragluteal area

What options do you have after an inadvertent enterotomy during an elective hernia repair (after repair of the enterotomy)?

• Abort the hernia repair; perform a primary tissue or biologic tissue repair; perform a delayed repair using prosthetic mesh in 3 to 4 days

What is an Amyand hernia?

• Hernia sac containing a ruptured appendix

What is a Bochdalek hernia?

• A posterior diaphragmatic hernia usually occurring on the left (Bochdalek = back and to the left)

What is a Morgagni hernia?

• An anterior parasternal diaphragmatic hernia

What is a Cooper hernia?

• A femoral hernia with 2 sacs that tracks into the scrotum or labia majorum through the femoral canal.

What is a Littre hernia?

• Hernia containing a Meckel diverticulum

What is a Spigelian hernia?

• Hernia through the linea semilunaris

What is a Hesselbach hernia?

• A hernia that is lateral to the femoral vessels and under the inguinal ligament

What is a pantaloon hernia?

• A hernia that straddles the inferior epigastric vessels representing both a direct hernia through the floor of the canal and an indirect hernia protruding through the internal ring

What is a Richter hernia?

• Incarcerated/strangulated hernia involving only 1 sidewall of the bowel

What is an intraparietal hernia?

• Hernia containing abdominal contents occurring between the layers of the abdominal wall

What is a Sports hernia?

• Characterized by a dilated superficial ring of the inguinal canal and chronic groin pain in athletes (not a true hernia)

Name the repair: approximation of the transversus abdominis aponeurotic arch to the iliopubic tract with the use of interrupted sutures beginning at the pubic tubercle and extending laterally past the internal inguinal ring with or without the use of a relaxing incision.

• The iliopubic tract

Name the repair: suturing the transversus abdominis and internal oblique musculoaponeurotic arches or conjoined tendon to the inguinal ligament.

• The Bassini repair

Name the repair: a multilayer imbricated repair of the posterior wall of the inguinal canal with a continuous running suture technique by superimposing running suture lines progressing from deep to more superficial layers (initial suture line—transversus abdominis aponeurotic arch to iliopubic tract, next suture line—internal oblique and transversus abdominis muscles and aponeuroses to the inguinal ligament).

• The Shouldice repair

Name the repair: the edge of the transversus abdominis aponeurosis is approximated to Cooper ligament with interrupted, nonabsorbable sutures; a transition suture is then placed to incorporate Cooper ligament and the iliopubic tract when the medial aspect of the femoral canal is reached; the transversus abdominis aponeurosis is then secured to the iliopubic tract lateral to the transition stitch; a relaxing incision is then made throughout the extent of the anterior sheath to near its lateral border.

• McVay (Cooper ligament) repair

Name the tension-free inguinal hernia repair: prosthetic nonabsorbable mesh is sutured to the aponeurotic tissue overlying the pubic bone medially continuing along the transversus abdominis or conjoined tendon superiorly and the iliopubic tract or the shelving edge of the inguinal (Poupart) ligament inferolaterally using nonabsorbable monofilament suture in a continuous fashion.

• Lichtenstein repair

Name the tension-free inguinal hernia repair: a cone-shaped plug of polypropylene is inserted into the internal inguinal ring and sewn to the surrounding tissues, occluding the hernia, and held in place by an overlying mesh patch (with or without sutures).

• Plug and patch repair

Name the tension-free inguinal hernia repair: a repair that uses a bilayered device with 3 polypropylene components (underlay circular patch, connector, and onlay patch) covers the posterior inguinal floor.

• Prolene hernia system (PHS) repair

Name the hernia repair: a hernia repair that utilizes an infraumbilical incision and blunt dissection to create a space beneath the rectus with placement of a dissecting balloon deep to the posterior rectus sheath and advanced to the pubic symphysis and inflated under direct laparoscopic vision.

• Totally extraperitoneal (TEP) repair

Name the hernia repair: a hernia repair that utilizes an infraumbilical incision to gain access to the peritoneal cavity directly; placement of two 5-mm ports lateral to the inferior epigastric vessels at the level of the umbilicus; creation of a peritoneal flap.

• Transabdominal preperitoneal (TAPP) repair

Name the hernia repair: a large piece of mesh is placed with an extensive fascial underlay in the retromuscular space on top of either the posterior rectus sheath or peritoneum.

• Stoppa repair

Name the hernia repair: large subcutaneous flaps above the external oblique fascia are created; a relaxing incision is performed on the lateral external oblique aponeurosis from the costal margin to the pubis; the external oblique is then bluntly dissected from the internal oblique with the option of performing further relaxing incisions (aponeurotic layers of the internal oblique, transversus abdominis, or posterior rectus sheath); primary fascial closure at midline. These techniques, when applied to both sides of the abdominal wall, can yield up to 20 cm of mobilization.

• Component separation technique