How are hernias classified? (5)
- Anatomical site- external abdominal, internal abdominal
- Congenital versus Acquired
- Reducible, incarcerated, or strangulated
- Contents of hernia- intestines, fat, greater omentum
- "true" versus "false"
What are types of external abdominal and internal abdominal hernias?
- External: umbilical, inguinal, femoral, scrotal
- Internal: diaphragmatic, hiatal
What is a true hernia versus a false hernia?
- a true hernia includes peritoneal lining and the defect in the body wall is lined by peritoneum; usually congenital
- a false hernia lacks a peritoneal sac and outside a normal abdominal opening; usually traumatic
What are 4 goals when fixing a hernia?
- return viable content to normal anatomical location
- close the opening to prevent recurrence (tension free)
- eliminate extra tissue in the sac
- use patient's tissue whenever possible (minimize use of extra materials, mesh, etc)
What are general surgical principals when it comes to repairing hernias? (5)
- careful dissection and hemostasis around hernia
- debride the edges of the hernia (but just enough to promote healing...you don't want tension on the site)
- preserve blood supply
- resect non-viable tissues
- thorough abdominal exploratory if traumatic hernia
If a peritoneal sac is present, you should first...
open the sac to inspect the contents, evaluate the vascular supply, and remove the sac and ligate the base
_________ is the worst enemy of hernia repairs.
Tension on the surgical site
What is you first choice to repair a hernia that is under tension or has inadequate tissue for closure without tension?
muscle flaps or endogenous tissue (if you can't do this, go to synthetic mesh...but you want to avoid this)
What do you use to close a hernia?
monofilament, delayed absorbable suture
What is the holding layer for abdominal body wall?
external rectus fascia
Where are traumatic abdominal hernias usually found?
prepubic region and flank
What concurrent condition is associated with umbilical hernias in dogs?
male dogs with cryptorchidism
Many _________ will resolve spontaneously by....
umbilical; as late as 6 months of age.
Describe the procedure usually used to repair umbilical hernias.
- find the neck of the hernia
- if reducible, replace contents to abdomen, ligate and incise the neck of the hernia
- if not reducible, carefully explore contents and determine viability of tissues, then replace contents and ligate sac
- debride edges and suture closed body wall
What are the types of hernias at the junction of hindlimb and body wall?
- inguinal hernias- bulging on abdominal wall, near inguinal ring
- scrotal hernias- bulging from inguinal ring to scrotal sac
- femoral hernias- bulging on the leg
Inguinal hernias can be caused by... (4)
- associated with obesity or pregnancy
- congenital (uncommon)
- traumatic (most common- cats attacked by dogs)
What are the normal contents of the inguinal canal?
- genitofemoral n
- external pudendal n., a., v.
- [males] spermatic cord
- [females] round ligament
Where are the vascular and nervous structures located within the inguinal canal (so you can avoid this when making your approach to repair a hernia)?
caudal medial aspect of canal
How do you approach an inguinal hernia for repair? (3)
- incision parallel to flank fold, avoiding caudomedial aspect of canal
- reduce contents and amputate the base of the hernial sac
- close the hernial sac and inguinal ring (external rectus fascia) separately
Describe post-operative care after hernia repair. (4)
- opioids for pain
- NSAIDs to reduce swelling, inflammation, and pain
- limit exercise for 4-6 weeks
- monitor for infection, dehiscence, and nerve/ vascular damage