15.4.2 Hernias And Surgical Umbilicus Flashcards
Define:
Hernia
Inguinal hernia
Hernia = Protrusion of an organ from the cavity where it normally resides, through a defect in the wall of that cavity.
Inguinal hernia = Protrusion of abdominal contents into the inguinal canal.
Patent processus vaginalis
- connects the scrotum to abdominal cavity
- where testes descends normally
- canal should close after birth
- ➡️ Hydrocele (only let fluid through)
- ➡️ Hernia (let bowel through)
Processes vaginalis
- Is an embryonic out-pouching of peritoneum within the groin along the path of testicular descent.
- Descent complete = obliteration of PPV occurs
- At birth, 80% of males have a patent processes vaginalis. This decreases to 40% at 2 years and 20% in adults
Pathophysiology of of patent processus vaginalis
- 99% of inguinal hernias in children are due patent processes vaginalis (PPV)
- If the PPV contains organs – inguinal hernia (most common):
➡️Small or large bowel (most commonly)
➡️Fallopian tube and, uterus or ovary in girls
➡️Appendix may be present
➡️The bladder (a sliding hernia) - If the PPV contains fluid – hydrocele
Different types on slide 4
Epidemiology + RF of inguinal hernias
- 50 % < 1 year
- 10 % bilateral
- 2 x more common on the right side
- premature babies and neonates = higher risk of complications
Risk factors:
- Males (5-10 more common)
- Family history
- Male twins
- Neonatal period
- Prematurity
Complications of hernia
- obstructed / incarcerated hernia
- strangulated hernia
- intestinal obstruction
- shock and septicemia
- full thickness necrosis
- testicular infarction
Obstructed (incarcerated) hernia
Def
Pathogenesis
Clinical signs
Def
- A hernia with contents persisting outside the abdominal cavity is obstructed.
- If it cannot be manually pushed back into the abdominal cavity it is
irreducible
- The smaller the child the higher the risk.
- In neonates more than the third become complicated
Pathogenesis:
- The obstructed bowel swells and develops oedema and bowel obstruction develops.
- Should the intra-luminal pressure exceed the systolic blood pressure, it may affect the blood supply of the bowel wall and full thickness necrosis may ensue.
Clinical signs:
- Sudden onset
- Severe pain
- Hard mass in inguinal area
- Intestinal obstruction with vomiting
- You cannot get above the mass.
Strangulated hernia
Def
Clinical signs
Def
- An obstructed hernia in which ischaemia ± necrosis develops.
Clinical signs:
- Pain
- Redness
- Tenderness
- Oedema of overlying skin ± abdominal wall
Intestinal obstructions
- Obstructed inguinal hernia is one of the 2 most common causes of small bowel obstruction.
- Fluid lost by nausea and vomiting as well as into third space may lead to dehydration and shock.
- An incarcerated hernia which contains an ovary or fallopian tube may strangulate but will not have signs of bowel obstruction.
Septicaemia and shock
Bacterial translocation may lead to septic shock
Full thickness necrosis
Ischaemia and infarcted bowel must be resected and repaired by means of an end-to-end anastomosis
Testicular infarction
Testicular infarction may occur in 10% of obstructed hernias. It appears as the testicular atrophy later
Omphalocoele (Exomphalos)
Def
Pathophysiology
Embryology
Classification
Def
- Congenital herniation of intra-abdominal contents through an opening in the umbilical ring
- covered by membrane
- look like cyst
- (Greek: Omphalos for belly-button and Coele for cyst)
Pathophysiology
- Incidence = 1/4000 live births
- The hernia contents are covered with a transparent membrane which consists of amniotic sac (+Wharton jelly)
- The umbilical cord arises from the apex of the sac and the umbilical, the vein and artery runs in the wall of the membranous sac
- Contents can contain midgut/liver/spleen/gonads
Embryology
- There is failure of fusion of the lateral abdominal wall around the umbilical cord
CLASSIFICATION:
(alters surgical management)
- Exomphalos minor (< 5cm diameter sheath defect)
- Exomphalos major (> 5cm sheath defect or contents include liver)
Omphalocele
Associated conditions
Associated conditions
Congenital anomalies are important and include:
- Malrotation is present in 100%.
- Chromosomal abnormalities (70%) e.g. Trisomy 13, 18, 21.
- Cardiac, central nervous system and genito-urinary abnormalities
- BECKWITH-WIEDEMAN syndrome: (also known as EMG syndrome = Examphalos, Macroglossia, Gigantism A genetic abnormality related to the short arm of chromosome 11. -> check for Hyperglycaemia
Clinical features of Beckwith-Wiedemann syndrome
- Congenital abdominal wall defect (omphalocele)
- Macroglossia (large tongue)
- Macrosomia/gigantism (big baby)
- Organomegaly
- Hypoglycaemia: Severe but temporary hypoglycaemia in neonatal period that can lead to brain damage or death if untreated
- Mental retardation
- Embryonal tumours (in older children) Babies with EMG syndrome also have an increased risk of solid-organ tumours.
Omphalocele
Clinical features
Antenatal:
- Antenatal ultrasound detection facilitates planned delivery in a tertiary unit.
- Assesses the size and content of omphalocele.
- Can detect associated abnormalities and/or test for it.
At birth:
- Defect through umbilical ring
- Bowel covered with a membrane.
- Umbilical cord is still attached.
