Hernia Flashcards
Define hernia
The protrusion of a viscus/organ through a defect of the wall containing cavity into an abnormal position
Describe how embryology can contribute to a hernia
Testicular development is determined by the y chromosome and it must produce testosterone to descend
1. The testis, guided by the mesenchymal gubernaculum, migrates down into the inguinal canal
2. The structures found in the scrotum (testis, vas, blood vessels) pass through the abdominal wall and pick up layers
3. These layers make up the coverings of the spermatic cord
4. A remnant of the peritoneal invagination (Processus vaginalis) may remain patent → fluid or abdominal contents can pass into it → hydrocoele or hernia
Explain how an umbilical hernia may arise
The umbilical ring allows passage of vessels through the abdominal wall muscles between mother and foetus
After birth and disintegration of the cord, the ring remains, with spontaneous closure typically by 5yo (growth of abdominal muscles and fusion of peritoneal and fascial layers)
Failure or delay in this process leads to the formation of an umbilical hernia
What is incarceration and strangulation of a hernia
Incarceration = abdominal viscera or omentum becomes stuck within the hernia (irreducible)
Strangulation = viscera becomes stuck in the hernia with compromise to their blood supply → ischaemia or necrosis
What are the types of hernia
Inguinal
Umbilical
Paraumbilical
Femoral
Epigastric
Congenital diaphragmatic
Exomphalos/omphalocoele
Gastroschisis
What is the cause of inguinal hernias, where is it most likely to be and what is the risk difference between age groups
Persistently patient processus vaginalis
Hernia emerges from the deep inguinal ring through the inguinal canal (usually INDIRECT)
More likely to be right sided (as left PV obliterates before the right)
The risk of incarceration is higher in infants than older children
Which hernia are babies more likely to get if born premature
Direct inguinal hernia as they weaker tissue that is more friable
What are the risk factors for an inguinal hernias
Preterm infants (esp. LBW)
Boys (as ovaries don’t leave the abdominal cavity)
Infants with chronic lung disease
Conditions causing abdominal fluid or increased abdominal pressure e.g. cystic fibrosis
CT disorder
What are the symptoms and signs of an inguinal hernia
Lump in the groin
- May extend into the scrotum or labia majora
- Usually asymptomatic, intermittent, visible on sraining
- Reducible unless incarcerated (tender, red, firm)
Non-transluminable (but may be in young patients)
Abdominal pain
Irritability
Nausea and vomiting
Swelling in the scrotum visible upon straining or crying
What is the management for an inguinal hernia
Surgery (herniotomy)
- First few months of life - urgent hernia repair (higher risk of strangulation)
- >1yo: elective surgery
Neonates: If reducible → elective herniorrhaphy repair
- <6w: correct within 2 days
- <6m: correct within 2 weeks
- <6yo: correct within 2 months
Most cases are performed as day cases, neonates and premature infants are kept in hospital overnight as there is a recognised increased risk of post operative apnoea.
What are the complications and prognosis of inguinal hernias
Incarceration
Herniotomy- recurrence, damage to vas deferens, testicular vessels, ascending ipsilateral testicle secondary to scarring
Excellent prognosis with surgical repair
What are the risk factors for an umbilical hernia
Prematurity
Afro-Caribbean
Down’s syndrome
Mucopolysaccharide storage devices
Low birth weight
Ehlers-Danlos syndrome
Hypothyroidism
What are the symptoms and signs of an umbilical hernia
Hernia:
- Painless
- Reducible
- More prominent on straining or crying
What is the management for an umbilical hernia
Observation: Typically resolves by 4-5 years of age (most by 12 months)
If it persists beyond 4-5yo → elective outpatient surgical repair
Large or symptomatic hernia (>1.5cm) → intermittent symptoms of incarceration or recurring pain → elective repair at 2-3yo
Incarceration → manually reduce with pressure + surgical repair within 24h (may require emergency op if it cannot be reduced)
+ safety net
What should be advised on safety netting for a hernia
Strangulation
Vomiting, pain
Unable to push the hernia in
Complete constipation, unable to pass flatus