Abdominal wall hernias Flashcards
Define hernias of the abdominal wall
An abnormal protrusion of abdominal contents though the fascia of the abdominal wall
List the contents of a hernia
Always contains a portion of the peritoneal sac May contain viscera, usually small bowel and omentum
Describe the aetiology of congenital abdominal hernias
Associated with developmental disorders e.g. persistent processus vaginalis, failure of complete obliteration of the umbilical opening
Describe the aetiology of acquired abdominal hernias
Weakness of the abdominal wall due to ageing or previous surgery. Risk increased in conditions that increase intra-abdominal pressure.
What terms are used to describe an abdominal hernia?
Reducible: contents can be fully restored to the abdominal cavity, spontaneously or with manipulation. Incarcerated: part or all of the contents cannot be reduced due to narrow neck and/or adhesions. Strangulated: twisting or entrapment compromises blood supply to the hernia ➔ obstruction and infarction
What may be seen on examination of a hernia?
Occur at weak spot May reduce on lying down, or with direct pressure May have expansile cough impulse
Name 5 common types of abdominal wall hernias
Inguinal hernia (commonest) Femoral hernia Incisional hernia Epigastric hernia Umbilical hernia
What is the commonest type of abdominal hernia?
Inguinal hernia
What is the M:F ratio for inguinal hernias?
8:1
How can inguinal hernias be classified?
Direct: medial to inferior epigastric artery Indirect: lateral to inferior epigastric artery
Differentiate between an indirect and direct inguinal hernia
Indirect: occurs at any age (usually young), congenital, lateral to inf epigastric a, often descend to scrotum, narrow neck ➔ more likely to strangulate Direct: uncommon in children and young adults, acquired, medial to inf epigastric a, rarely descend to scrotum, wide neck ➔ rarely strangulate
Name 2 risk factors for indirect inguinal hernias
Prematurity Male
Name 3 risk factors for direct inguinal hernia
Male Obesity Constipation Chronic cough Heavy lifting
Describe the presentation of inguinal hernias
Lump in the groin May have sudden pain Expansile cough impulse Ache or dragging sensation, especially at the end of the day
Outline the management of inguinal hernias
Reassurance if small and asymptomatic Symptomatic hernias or Hx of incarceration or bowel obstruction ➔ offered hernia repair -Consider hernia truss: supports tissue and relieves pain Hernia repair: reduction or excision of sac, closure of defect with minimal tension.
What structure do indirect inguinal hernias travel through?
Inguinal canal: transmits the spermatic cord/round ligament, and the ilioinguinal nerve.
What is the content of the spermatic cord?
Vessels: testicular a, cremasteric a, artery of vas deferens Nerves: genital branch of genitofemoral, autonomic supple to testicles, ilioinguinal n Structures: vas deferens, pampiniform venous plexus, testicular lymphatics Coverings: external spermatic fascia, cremasteric fascia, internal spermatic fascia
What anatomical location is most commonly associated with direct inguinal hernias?
Hesselbach’s triangle: -Inguinal ligament (inferiorly) -Inferior epigastric artery (laterally) -Lateral border of rectus abdominis (medially)
Outline the anatomy of the femoral canal
Anterior: inguinal ligament Posterior: pectineal ligament Medial: lacunar ligament Lateral: femoral vein
Which sex is most likely to have a femoral hernia?
Women
Describe the presentation of femoral hernias
Lump in the groin, lateral and inferior to the pubic tubercle, medial to femoral pulse Lower abdominal pain if incarcerated *30% present as emergencies due to high risk of strangulation
Name 3 differentials for femoral hernias
Low presentation of inguinal hernia Femoral canal lipoma Saphena varix (dilatation of proximal long saphenous v) Hydrocele Spermatic cord hydrocele Lymphadenopathy Psoas abscess Varicocele
What is the most concerning complication of femoral hernia?
Strangulation of the femoral hernia. High risk due to the narrow opening and rigid boundaries of the femoral canal.
Describe the presentation of a strangulated hernia
Red and tender Tense and irreducible Colicky abdominal pain Distension Vomiting
Outline the treatment of femoral hernias
Due to high risk of strangulation, all femoral hernias should be repaired as an elective process. -Low approach (Lockwood’s) -Trans-inguinal approach (Lotheissen’s) -Thigh approach (McEvedy’s) Truss (conservative) has no place in management
What can be done to reduce the rate of recurrence of femoral hernias?
Narrowing of the femoral canal after hernia repair
State 3 differences between true umbilical hernias and paraumbilical hernias
True: occur through the umbilical cicatrix, almost always congenital, commoner in Afro-Caribbean races. Para: occur through the paraumbilical tissue, acquired, common in obese and parous women.
Describe the pathophysiology of epigastric hernias
Defects in the line alba between the xiphisternum and umbilicus, at sites of penetration of nerves and vessels.
Describe the presentation of umbilical hernias
Small, centrally places within the umbilicus Often contains pre-peritoneal fat Rarely contains bowel or omentum May be painful, but rarely strangulates
Describe the presentation of paraumbilical hernias
Variable size, up to moderate Many potential locations Distorts shape of umbilicus May contain bowel or omentum Often painful and occasionally strangulates
Describe the presentation of epigastric hernias
Variable size, up to large Always along midline Most frequently only contains pre-peritoneal fat Moderate risk of strangulation
Outline the management of umbilical hernias
<1cm ➔ almost always spontaneously close by 5yr >1.5cm or in child >4yr ➔ repair Symptomatic hernias or high risk complications ➔ repair
Name 3 factors that predispose to incisional herniation?
Wound infection Steroid use, anaemia, or malnutrition pre-op Midline laparotomy Poor surgical technique in abdominal closure
When do incisional hernias most commonly present?
Up to 5yr post-op
What significant complication can occur following large incisional herniation?
Viscera are often permanently herniated If this occurs for a long period of time, the abdominal wall muscles retract ➔ small abdominal cavity that may not contain all the retracted viscera.
Outline the management of incisional hernias
<4cm (S) ➔ simple sutured repair >4cm (M or L) ➔ mesh repair -Above umbilicus: between post rectus sheath and rectus abdominis muscle -Below umbilicus: pre-peritoneal space *Arcuate line
What are the signs of a strangulated hernia?
Irreducible Tender Overlying erythema or cellulitis
Why is it important to identify a strangulated hernia?
The region becomes ischaemic and subsequently gangrenous. Gangrene can lead to perforation of the bowel with ensuing peritonitis.
What is the management of a strangulated hernia?
Emergency surgery within 6hr of strangulation
What feature increases the risk of a hernia strangulating?
Narrow opening in the containing wall
