Definition
A hernia is the protrusion of a peritoneum-lined sac through some defect in the abdominal wall. Abdominal wall hernias are the most common surgical procedure. Hernias are a leading cause of disability and work loss. Types include the following:
A.Umbilical hernia: Occurs when the intestinal muscles fail to close around the umbilicus, allowing the omentum and/or intestines to protrude into the weaker area.
B.Incisional hernia: Caused by a defect in the abdominal musculature that develops after a surgical incision.
C.Epigastric hernia: Protrusion of fat or omentum through the linea alba between the umbilicus and the xiphoid. Epigastric hernias are generally less than 2 cm in diameter.
D.Diastasis recti: Acquired hernia most often due to pregnancy and obesity. The right and left rectus muscles separate, but there is no facial defect.
E.Obturator hernia: Follows the path of the obturator nerves and muscles
Incidence
A.Umbilical hernias are more common in African American infants, women, and the elderly. This type of hernia has a higher risk of incarceration and strangulation and therefore a greater mortality because the large bowel is frequently entrapped.
B.Epigastric hernias are most common in men 20 to 50 years old.
C.Incisional hernias typically are noted in the early post-operative period; however, there is an increase in incisional hernias during pregnancy. These iatrogenic hernias occur in 2% to 10% of abdominal operations. In addition to hernias, separation of the recti abdominis muscles (diastasis recti) is often caused by pregnancy or obesity.
D.Obturator hernias occur more commonly in females. Females have a larger canal diameter, which is noted predominantly in thin elderly women.
Pathogenesis
A.Incisional hernias are due to failure of fascial tissues to heal and close.
B.Epigastric hernias are defects in the abdominal mid-line between the umbilicus and the xiphoid process. They are usually related to a congenital weakness, increased intra-abdominal pressure, surrounding muscle weakness, or chronic abdominal wall strain.
C.An umbilical hernia is caused by failure of the umbilical ring to obliterate after birth. In the infant, the umbilical ring often closes spontaneously within the first 1 to 2 years of life. Increased abdominal pressure or congenital defects cause abdominal hernias that allow abdominal contents to protrude through the opening defect. In adults with an umbilical hernia, obesity increases the danger of incarceration.
Predisposing Factors
A.Congenital predisposition.
B.Gender.
C.Obesity.
D.Multiparity.
E.Cirrhosis and ascites.
F.Trauma or straining.
G.African American ancestry.
H.Chronic cough; can precipitate or worsen herniation.
I.Previous abdominal surgery.
J.Straining, coughing, and sneezing.
K.Straining with chronic constipation.
L.Incisional hernia factors:
1.Smoking.
2.Connective tissue disorder.
3.Infection.
4.Malnutrition.
5.Immunosuppressive medications.
M.Age: Obturator hernias occur predominantly in the elderly.
N.Maternal smoking is associated with an increased prevalence of omphalocele and gastroschisis.
Common Complaints
A.Asymptomatic—may only be detected on routine physical examination:
1.Swelling or fullness at the hernia site.
2.Varying degrees of discomfort.
3.The only sign of a hernia may be increased irritability.
4.Bulge of abdomen or of a previous scar.
B.Symptoms aggravated by cough and straining.
Other Signs and Symptoms
A.Incisional: Bulge through incision wall (may be intermittent).
B.Epigastric: Small, usually painless subcutaneous mass.
C.Umbilical:
1.Adult: Vague, intermittent pain; palpable mass.
D.Reducible or irreducible: Signs and symptoms are related to the degree of pressure of their contents rather than to size. Most patients are asymptomatic or complain of only mild pain.
E.Strangulated: Colicky abdominal pain, nausea, vomiting, abdominal distension, hyperperistalsis.
Subjective Data
A.Review onset, duration, and course of symptoms.
B.Ask the patient about previous abdominal surgeries, wound infection, and pregnancies.
C.Review history of straining, trauma, or physical labor.
D.Determine if the patient has signs and symptoms of strangulation of entrapped bowel: pain, nausea, vomiting, distension, and fever.
E.Determine if the patient can reduce hernia.
F.Ask the patient whether the hernia is enlarging and uncomfortable.
G.Review the patient’s bowel history, specifically constipation.
H.Review the patient’s history for chronic obstructive pulmonary disease (COPD)/chronic cough.
I.Review the patient’s history for symptoms of obstructive uropathy.
J.Review how the hernia affects the patient’s activities of daily living (ADLs).
Physical Examination
Examination is the same for all types of abdominal hernias. Perform exam while the patient is standing and supine. History and physical examination are the best means of diagnosing hernias.
A.Check temperature (if indicated), pulse, respirations, and blood pressure (BP).
B.Inspect:
1.Inspect contour and symmetry of the abdomen for bulges or masses. The bulge may be asymmetric.
2.Inspect irreducible hernias for discoloration, edema, and ascites.
3.Assess:
a.Have the patient perform Valsalva’s maneuver while standing.
b.Have the patient lie supine, lift head from exam table, and then bear down to tense abdomen.
C.Auscultate all quadrants of the abdomen for bowel sounds.
D.Percuss liver, spleen, and abdomen.
E.Palpate:
1.Palpate the entire abdomen for masses, hepatomegaly, and ascites. Umbilical hernias may be
obscured by subcutaneous fat.
2.Palpate the groin.
3.Palpate the hernia to try to gently reduce it.
Diagnostic Tests
A.None is required if the hernia is easily reducible (depending on the type of hernia).
B.Complete blood count (CBC): White blood count (WBC) increased, hematocrit (Hct) increased.
C.Electrolytes: Na+ increased or decreased.
D.Abdominal radiography: Reveals abnormally high levels of gas in bowel.
E.Ultrasonography, if strangulation is suspected.
F.CT scan of the abdomen and pelvis may be indicated.
Differential Diagnoses
A.Abdominal hernia.
B.Diastasis recti.
C.Ascites.
D.Abdominal wall tumor or cyst.
E.Bowel obstruction.
Plan
A.Patient teaching:
1.Discuss the hernia and available options for treatment.
2.Teach the patient signs and symptoms of strangulation.
3.Instruct the patient to refrain from heavy lifting.
4.Advise the patient to wear a support garment.
B.Medical and surgical management:
Reduction should not be attempted if there are signs of inflammation or obstruction. Reduction of a strangulated bowel leads to persistent ischemia or necrosis with no clinical improvement.
1.Try to reduce hernia unless strangulated. See Section II: Procedure for Hernia Reduction (Inguinal/Groin)
:
a.Easily reducible: Abdominal contents can be easily returned to their original compartment. Allows symptomatic relief.
b.Incarcerated: Cannot be returned to its original compartment. The incarcerated tissue may be bowel, omentum, or other abdominal contents.
c.Strangulated: Surgical emergency—blood supply to the herniated tissue is compromised.
2.Do not try to reduce strangulated hernias because reduction can cause gangrenous bowel to enter peritoneal cavity.
3.A truss fits snugly over a hernia to prevent abdominal contents from entering the hernial sac. It does not cure a hernia and is used only when the patient is not a surgical candidate.
4.Surgery may be done laparoscopically or through an open procedure and by sutured or mesh repair, depending on the age of the person, type and size of the hernia, and the presence of strangulation.
Follow-Up
A.Instruct the patient to call the office if fever or severe pain occurs. Otherwise, no follow-up is required unless for post-operative repair. Postoperative follow-up is with the physician who performed the surgery.
Emergent Issues/Instructions
A.Consult a physician or send the patient to the ED if the patient has abdominal tenderness, discoloration, or edema at the site; fever; or signs of bowel obstruction.
Consultation/Referral
A.A surgical consultation may be warranted.
Individual Considerations
A.Pregnancy:
1.Incisional hernias are more common during pregnancy because of increased intra-abdominal pressure.
2.Bowel obstruction secondary to previous scarring may also be seen and is most common when the uterus emerges from the pelvis early in the second trimester, when the uterus is maximally distended at term, and in the immediate puerperium when the uterus promptly decreases in size.
3.Maternal smoking has been associated with an increase prevalence of omphalocele and gastroschsis.
B.Geriatrics:
1.Because of the anatomic position of the obturator hernia, the presentation is more common as a bowel obstruction than as a protrusion of bowel contents:
a.The geriatric population is more prone to develop electrolyte and acid–base imbalances from obstruction.
2.The geriatric population has a higher rate of ventral hernias attributed to the loss of muscle strength in the anterior abdominal wall and the prevalence of comorbidities that lead to an increased intra-abdominal pressure.