Final Exam - Hernias Flashcards
what is an abdominal hernia?
any defect in the external abdominal wall that may allow protrusion of the abdominal contents
what is a congenital hernia?
defect that is present at birth although they may not herniate until later
what is an acquired hernia?
defect secondary to a primary cause such as trauma, surgery, & degeneration
what is an internal hernia?
hernia that is within the body cavity, diaphragmatic
what is an external hernia?
body wall herniation
in regards to hernia definitions, what is a ring?
the actual defect
in regards to hernia definitions, what is contents?
the organs & the tissues in the hernia
in regards to hernia definitions, what is a sac?
the tissue holding the contents - may or may not be present
in regards to hernia definitions, what is a true hernia?
mesothelium lines the sac of the hernia
in regards to hernia definitions, what is a false hernia?
no mesothelium lining, so there is no sac - acute or acquired & more at risk for adhesions
in regards to hernia definitions, what is a reducible hernia?
free to move in & out of sac
in regards to hernia definitions, what is an incarcerated hernia?
hernia that has contents stuck in the sac - non-reducible
in regards to hernia definitions, what is a strangulated hernia?
hernia with obstruction of blood supply that leads to necrosis - emergency
what are some clinical signs of hernias?
a bulge from the body wall that shouldn’t be there that may or may not be painful (strangulation of contents causes pain)
dysfunction of entrapped organs
how are hernias diagnosed?
rads, ultrasound, palpation, auscultation, & exploration
what is the general surgical treatment for hernias?
use an abdominal approach for traumatic hernias - return viable contents to normal position & remove non-viable contents (do not untwist!)
remove the hernia sac & close the ring using the patient’s own tissue working to minimize tension - can use mesh or autologous graft
what are some complications of hernia surgery?
recurrence, too much tension, poor closure, inadequate tissue, primary cause still present, & infection
what is the pathophysiology of hernias?
loss of abdominal domain *
what does the success/prognosis of a patient with a hernia depend on?
severity of functional alterations, cause of hernia, location of hernia, & contents of hernia
what are the 3 categories given for pathophysiology of hernias?
- space occupying - diaphragmatic
- obstruction - normal function altered, luminal obstruction (bladder, intestines, uterus)
- strangulation - decreased blood supply leading to necrosis
where do ventral hernias occur? what generally causes them?
occur on or adjacent to midline - traumatic or congenital
what is the most common abdominal hernia?
umbilical hernia
what causes an umbilical hernia?
inherited
results from failure of the umbilical ring to close completely - may be associated with other congenital defects such as cryptorchidism
how should you position an animal with a suspected umbilical hernia for palpation & reduction?
dorsal recumbency
when can you use conservative treatment for an umbilical hernia?
small hernias in young dogs - may close up to 6 months of age
when do you need to use surgery for an umbilical hernia?
if the hernia is large enough for a loop of intestine to pass through it - about 1 cm
resect & invert hernial sac
when is umbilical hernia repair typically performed? what suture & pattern is used?
on an elective basis concurrently with an OHE
monofilament in simple interrupted appositional or tension relieving pattern - can use synthetic mesh or releasing incisions on large defects if needed
what is an example of a cause of an anatomic inguinal hernia?
inguinal canal is larger & shorter in females
what is an example of a hormonal cause of an inguinal hernia?
estrogen may enlarge & weaken the inguinal rings
what is an example of a metabolic cause of an inguinal hernia?
obesity
what type of inguinal hernia is more common, direct or indirect?
indirect
what is the difference between a direct & indirect inguinal hernia?
direct inguinal hernia - shows a bulge from the posterior of the inguinal wall
indirect inguinal hernia - hernia passes through the inguinal canal & into the groin
what runs through the inguinal canal?
vaginal process/tunic
spermatic cord
genitofemoral nerve
external pudenal artery & vein
what is the process of a surgical repair for an inguinal hernia?
incision parallel to flank fold or ventral midline - ventral midline allows for evaluation of both rings & avoids dissection of mammary tissue
expose the sac, evaluate contents, reduce contents, ligate & amputate sac, close defect
don’t obstruct vessels with closure at caudomedial aspect of ring
what is a scrotal hernia?
subcategory of indirect inguinal hernia that affect males where the hernia contents lie within the scrotum - rare
T/F: in scrotal hernias, strangulation of contents is common
true
what is associated with scrotal hernia repair?
increased incidence of testicular tumor development - hernia repair should not compromise normal structures
what are some potential locations of traumatic hernias?
inguinal, prepubic, or paracostal - will occur at the site of the trauma, & there may be multiple sites if the hernias are the result of bite wounds
what are some causes of traumatic hernias?
HBC, kicked, fell - no mesothelium lined sac
what should you do if you have an animal present with a traumatic hernia?
look for other injuries - cardiovascular, orthopedic, respiratory, gi, & urinary
what is the physiology of a prepubic tendon rupture?
avulsion of the prepubic tendon off of the cranial aspect of the pubis usually due to blunt abdominal trauma
how is a prepubic tendon rupture corrected surgically?
repaired through a ventral midline incision with the rectus abdominis muscle attached to the pubis using polypropylene through predrilled holes in the pubis
what is the number one cause of incisional hernias? what are some other causes?
technical error
infection, steroids, fat, increased pressure
what is an incisional hernia?
any factor that increases pressures or weakens the suture line predisposed the incision to herniation
how can you reduce the risk of incisional hernias?
use appropriate suture material, placement, & post-op care
what is the exception where you should take an animal to surgery immediately with a diaphragmatic hernia?
if the stomach is in the thorax causing respiratory distress - need to decompress stomach with a needle through the thoracic wall
what should you do if you have an animal present with a diaphragmatic hernia?
not necessarily an emergency - treat shock & give supplemental oxygen if needed
how is a diaphragmatic hernia diagnosed?
radiographs - 97% have loss of line of diaphragm, obscured/displaced cardiac silhouette
viscera in the thorax is diagnostic - can also use ultrasound
how should the patient be prepped for surgical repair for a diaphragmatic hernia?
minimize anesthetic time - surgeon ready in OR & elevate the patient head/thorax during prep/induction/surgery
what is the repair procedure for a diaphragmatic hernia?
contents are reduced carefully
enlarge diaphragmatic rent if needed incise away from viscera/vessels
intrathoracic liver may be friable
adhesions may present because it is a false hernia
what complications may be associated with a diaphragmatic hernia?
adhesions, may extend into a thoracotomy (median sternotomy), great vessels are involved, & a partial lung or liver lobectomy may be necessary
how should you close an acute diaphragmatic hernia?
begin dorsally, proceed ventrally in a continuous suture pattern
evacuate air from the thorax using a chest tube transdiaphragmatically
how should you close chronic diaphragmatic hernias?
diaphragmatic advancement - circumcostal sutures
patch with omentum, muscle, mesh
freshen edges of rent
may see re-expansion pulmonary edema, so leave air in thorax & remove over 8-12 hours through a chest tube
what type of hernia is a PPDH?
congenital - affects dogs & cats
what is the pathophysiology of PPDH?
abnormal development of transverse septum that herniates into the pericardial sac
how is PPDH diagnosed?
rads
what clinical signs may be seen with PPDH?
CS specific to any obstruction
can develop at any age
respiratory compromise & cardiac tamponade
what are some concurrent abnormalities seen with PPDH?
sternal defects
cranial midline abdominal wall hernia, umbilical hernia, cardiac defects, & pulmonary vascular disease
what treatment can you do for an asymptomatic PPDH patient?
conservative treatment but they will never get more stable
what surgery is recommended for a symptomatic PPDH patient?
ventral midline celiotomy
what causes perineal hernias?
weakness & separation of the pelvic diaphragm - dilation/deviation of the rectum & herniation of abdominal organs
what is the most common anatomic location of perineal hernias? where is it?
caudal - between leviator ani, coccygeus, & external anal sphincter m.
where is a sciatic perineal hernia located?
between coccygeus m. & sacrotuberous ligament
where is a dorsal perineal hernia located?
coccygeus & levator ani m.
where is a ventral perineal hernia located?
between ischiourethralis, bulbocavernosus, & ischiocavernosus m.
what clinical sign may be suggestive of a perineal hernia involving the bladder?
inability/straining to urinate
bladder retroflexion
what is the etiology behind perineal hernias?
hormones - intact male dogs
straining to defecate - prostatic disease, cystitis, urinary tract obstruction
for abdominal hernias, presentation & diagnosis depends on what?
etiology, location, & tissues involved & their status
T/F: regardless of etiology, most hernias will present as a subcutaneous swelling or mass with diaphragmatic defects being different
true
what are some differentials for abdominal hernias?
abscess, cellulitis, hematoma, seroma, neoplasia, granuloma, & muscle avulsion
what are the basic principles of hernia repairs?
excise devitalized tissues
return viable contents to normal location
repair the defect
use the patient’s own tissues when possible
what does the prognosis of a patient with a hernia depend on?
etiology, patient status (metabolic & concurrent injuries), & status of hernial contents
what is a femoral hernia?
herniation through the femoral canal - palpate swelling on medial thigh caudomedial to the femoral vessels
what can cause a femoral hernia?
blunt trauma to the abdomen
what should you be careful with in repair of a femoral hernia?
avoid compromising nerves & vessels
a femoral hernia looks similar to what other hernia type?
inguinal hernia
