common abdominal hernias Flashcards
Common abdominal hernias include:
o Umbilical, inguinal, diaphragmatic, peritoneal-pericardial, scrotal, perineal, hiatal
What is a hernia?
a protrusion of an organ through the wall of its cavity
o Composed of ring (muscle), sac (peritoneum), and contents
Key principles when repairing a hernia:
- ensure the viability of entrapped hernia contents
- reduce the hernial contents to normal location
- achieve primary closure of the hernia defect
Hernia repair / Herniorrhaphy -Terminology
Strangulation:
Incarceration:
- strangulation - entrapment of viscera and obstruction of blood supply
- incarceration - Contents are irreducible and contraction of scar tissue at the hernia ring may result in delayed signs +/- Strangulation
Umbilical Hernia
- etiology
- concurrent conditions?
- who gets it?
- Congenital
- Hereditary
- +/- Cryptorchidism
- Umbilical ring fails to close
- Young animals, any breed
umbilical hernia clinical signs / diagnosis
- Soft, round mass or swelling at umbilical scar
- Obvious with large hernias
- Depending on size > Acute GI signs – think incarcerated viscera
- Look for other congenital defects!
umbilical hernia - treatment for a simple hernia
- May close spontaneously < 6 months
- Skin incision over hernia
- Return contents (usually just fat)
- Debride edges and suture
- Delay until time of spay or neuter
umbilical hernia - treatment for a complicated hernia
- If GI signs related to hernia, consider early intervention
- Full exploratory
- Check intestinal viability
- Close hernia at time of abdominal closure
Inguinal Hernia
- prevalence vs umbilical
- what is it?
- etiology? who gets it?
- Less common than umbilical
- Defect in inguinal ring allows organs to herniate
<><> - Congenital > male dogs
<><> - Acquired (most common) > Middle, aged, intact bitches (Toy breeds and Shar Pei)
> Herniated uterus could occur at time of pregnancy
Inguinal Hernia Clinical signs, diagnosis
o Painless, bi- or unilateral inguinal mass; >left vs right
o Incarceration: vomiting, painful to touch, febrile
o Suspected on historic and physical exam findings, confirmed by manual reduction of hernia and palpation of hernia ring
inguinal hernia surgical treatment
- Ventral midline incision (or right over hernia if prepuce is in the way) to allow for inspection of both inguinal rings (other ring will likely be affected as well)
-Allow for access to abdominal cavity for complicated hernias - Ensure vessels and nerve exiting inguinal ring not constricted!!
<><><>
o Amputate and close sac with PDS, or push back in > when closing ensure vessels and nerves exiting the inguinal ring aren’t constricted (do not completely tie off, must leave space)!
inguinal hernia repair prognosis? post-op instructions?
- Prognosis is very good for uncomplicated hernias with surgical intervention
- Post-operative exercise restriction
Diaphragmatic Hernia (DH)
- etiology
- character of the hernia
- Most commonly traumatic (~85%), rarely congenital
- Caused by a sudden increase in intra-abdominal pressure, usually due to trauma
o Herniation of viscera immediate
o No hernial sac
o Adhesions of organs can occur with chronicity (makes repair challenging)
Diaphragmatic Hernia -Clinical Signs
- There is a wide range of presenting signs, from no clinical signs to respiratory distress
<><> - In chronic diaphragmatic hernias, see acute to chronic GI signs, such as anorexia/vomiting
- as just a regular family pet thats not working too hard, they may not even show that many signs even with a quite bad hernia
diaphragmatic hernia diagnosis
Diagnosis via thoracic/abdominal radiographs +/- contrast study
o Will see hollow, viscous structures in the thorax and no diaphragm silhouette
o Can also use thoracic ultrasound or CT
Should all diaphragmatic hernias be repaired?
o Not all DH need to be repaired; many animals can still have a good quality of life with minimal pulmonary reserve
<><>
o Acute DH (likely respiratory distress) > surgery
o Chronic DH + clinical signs > referral surgery due to adhesions (sternotomy / thoracotomy potentially needed)
o Chronic DH + no clinical signs > ?? would we even know about this????
why can it be difficult to return organs to the abdomen in chronic diaphragmatic hernia cases?
Abdominal wall shrinks due to lack of organs
should we radiograph the thorax after trauma? why
- Always image the thorax post-trauma
- There may be DH due to impact
Diaphragmatic Hernia -Preoperative considerations
- Ensure cardiovascular stability
- Rapid dilation of stomach in thorax may lead to acute decompensation —> orogastric tube
- Minimize stress
Diaphragmatic Hernia - Surgerical approach, tips and tricks
o Ventral midline celiotomy, but be prepared for caudal sternotomy (shave and prep everywhere)
o May need to enlarge hernia in chronic cases to reduce contents (incarceration)
o Extirpate falciform ligament
o Balfour retractors (gently)
o Use gentle digital traction to reduce abdominal organs; beware of adhesions!
o Assess the entire diaphragm
> Radial vs circumferential tear?
o Pack off abdominal contents with lap sponges
o Place thoracic drainage catheter or thoracostomy tube at this point to prevent pneumothorax
o Use 0 to 3-0 long-acting suture (PDS) in a simple continuous pattern
> Use circumcostal sutures to reappose diaphragm if circumferentially torn
Diaphragmatic Hernia - Surgical considerations for chronic DH
In cases of chronic DH, referral is often preferred
o Organs may need to be removed due to loss of domain
o Abdominal closure may be challenging
o Be prepared, always discuss with owner beforehand as don’t know how things will go (not worth if often for older
animals who are currently okay)
o May need mesh for herniorrhaphy, fascial release for linea alba closure
Diaphragmatic Hernia -Postoperative care
o Do not obtain a negative intra-thoracic pressure immediately (pulmonary re-expansion edema, esp in cats)
o Leave thoracic drainage catheter ~24 h
o Good prognosis for uncomplicated cases
o Take post-operative radiographs, recheck at 6-12 weeks
Peritoneo-Pericardial Diaphragmatic Hernia
- etiology, how does it arise? what is it?
- who gets it?
- concurrent conditions?
- Congenital abnormality
- Communication between abdomen and pericardial sac
- abdominal contents drawn into pericardial sac with inspiration
- Congenital in Weimaraners/Maine Coon
- Often see other concurrent cardiac and sternal congenital defects
Peritoneo-Pericardial Diaphragmatic Hernia -Clinical signs
Wide range of clinical signs – may be an incidental finding
o GI signs: anorexia, vomiting, diarrhea (> dogs) o Respiratory (> cats)
o Exercise intolerance/depression
Peritoneo-Pericardial Diaphragmatic Hernia -Physical exam
radiograph findings
- muffled heart sounds
- heart murmur
- feel ventral abdominal wall/sternal defects
- increased respiratory rate/effort
o Radiographs: no distinct diaphragmatic silhouette, viscous structures in pericardial area
Should all PPDH be Repaired?
Do we operate on incidentally found PPDH?
- depends on the family, could have the same challenges in older animals on reducing these contents if there are adhesions
- may have to go into thorax
Peritoneo-Pericardial Diaphragmatic Hernia -
- Surgical Treatment?
- complications?
- prognosis?
o Ventral midline celiotomy +/- sternotomy
- suture diaphragm closed ONLY
- evacuate air from pericardium +/- thorax (can use red rubber catheter; avoid pneumopericardium)
o Complications include intraoperative adhesions, post-operative pericardial effusion and recurrence (rare)
- Prognosis generally very good
