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Inguinal Hernia 549

Inguinal Hernia Client Education
Sheet
VetBooks.ir Diseases and Disorders
PHYSICAL EXAM FINDINGS
BASIC INFORMATION
lyte imbalances.
• Depends on size and contents of hernia • Chemistry panel may indicate mild electro-
Definition ○ Hernia contents may include omentum/ • Perform fine-needle aspiration if deemed
Defect in the inguinal ring, through which fat (most common), ovaries, uterine horns, appropriate but only under ultrasound
abdominal contents can protrude intestine, bladder guidance to avoid perforation of strangulated
• Uncomplicated inguinal hernia intestinal loop or gravid uterus.
Epidemiology ○ Painless, unilateral or bilateral mass with
SPECIES, AGE, SEX a soft, doughy consistency Advanced or Confirmatory Testing
• Acquired: middle-aged to older, intact female ○ Mass is typically reducible (place in dorsal • Survey abdominal radiographs
dogs recumbency to palpate) ○ Displaced uterus, intestines, urinary
• Congenital: young male small breeds; ○ Enlarged inguinal ring is palpable just bladder
testicular descent likely delays inguinal ring proximal and axial to the femoral triangle. ○ Loss of caudal abdominal and inguinal
narrowing ○ Hernia contents tracking along round detail suggestive of herniation, although
• Uncommon in cats ligament in females may appear perineal. not definitive
• Complicated inguinal hernia • Contrast radiography
GENETICS, BREED PREDISPOSITION ○ Palpation less helpful due to swelling ○ Retrograde contrast cystourethrogram to
• Acquired hernias ○ Mass is often firm, nonreducible, and determine position of bladder
○ Toy breeds are overrepresented. painful. Overlying skin is bruised/ ○ Upper gastrointestinal (GI) contrast
• Congenital hernias erythematous. studies are not recommended for evalu-
○ Predisposed breeds include basenji, • Always palpate contralateral side; 35% are ation of intestinal loops because of the risk
Pekingese, poodle, Cairn terrier, and West bilateral at time of diagnosis. of vomiting and subsequent aspiration.
Highland white terriers • Abdominal ultrasound helps determine con-
○ Polygenic inheritance suspected in cocker Etiology and Pathophysiology tents and timing of surgery for nonreducible
spaniels and dachshunds • Pathogenesis is uncertain hernias.
• Traumatic inguinal hernia: no specific • Anatomic: females seem predisposed due to • Abdominal contrast CT useful for large,
predispositions (rare) a shorter, wider inguinal canal. complicated hernias or in cases of blunt
• Hormonal: sex hormones (estrogen) weaken abdominal trauma.
RISK FACTORS the collagen in connective tissues.
• Intact female, during or shortly after estrus • Nutritional/metabolic TREATMENT
or with pregnancy ○ Weakening of the abdominal wall sec-
• Obesity ondary to glucocorticoid administration Treatment Overview
(autonomous or iatrogenic) • Inguinal hernias are best repaired at time
ASSOCIATED DISORDERS ○ Weight of pregnant uterus or intra- of diagnosis because delay can result in a
• Perineal hernia abdominal fat stretches weakened inguinal more difficult procedure and greater risk of
• Obesity ring. complications.
• Cryptorchidism • Traumatic: disruption/weakening of caudal • Immediate surgical intervention is indi-
abdominal muscles; rarely caused in isolation cated for bladder, intestinal, or uterine
Clinical Presentation without other hernia (femoral or prepubic incarceration; clinical signs of peritonitis;
DISEASE FORMS/SUBTYPES tendon) or intractable pain.
• Indirect inguinal hernia
○ Abdominal viscera herniate within the DIAGNOSIS Acute General Treatment
vaginal process. • Goal: reduction or resection (if nonviable)
○ Scrotal hernia in males (vaginal process Diagnostic Overview of hernia contents, ligation of hernial sac,
is continuous with scrotum) Diagnosis is based largely on physical exam. and tension-free closure of hernia ring
○ Narrowing of vaginal process at inguinal Vomiting, abdominal pain, and depression • Herniorrhaphy: must understand regional
ring may cause organ entrapment/ suggest obstructed or devitalized intestine. anatomy (e.g., exit point of genitofemoral
strangulation. Diagnosis is most often confirmed with manual nerve and external pudendal vessels)
• Direct inguinal hernia reduction of hernia contents and palpation of ○ An abdominal approach by a ventral
○ Less commonly seen an enlarged hernial ring(s). Imaging studies midline incision is recommended for
○ Organs pass through inguinal ring adjacent may be useful for complicated hernias. exploration because it allows simpler
to evagination of the vaginal process. closure.
○ Usually larger defect than indirect Differential Diagnosis ○ Alternative: external approach to inguinal
hernias • Abscess ring by a ventral midline skin incision
• Inguinal lymphadenopathy with subcutaneous dissection to hernia
HISTORY, CHIEF COMPLAINT • Mammary tumor sac (avoids mammary tissue and allows
• Swelling in the inguinal region • Lipoma bilateral access)
• No systemic signs if omentum/fat herniated • Inguinal fat pad ○ Complicated hernias may require com-
or if no organ entrapment • Mastitis: firm, enlarged, painful mammary bined approach for reduction of hernia
• If organ entrapment/strangulation (devital- glands contents and ligation of hernia sac.
ized tissue) within the hernia: abdominal ○ Laparoscopic repair reported
pain, vomiting, diarrhea, dysuria/stranguria, Initial Database ○ Primary repair is preferably performed
vaginal discharge/hemorrhage, bruising, • CBC may show a leukocytosis with a left with patient’s own tissues by partial closure
lethargy, depression shift if intestinal strangulation is present. of inguinal ring.

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