GI Abnormalities Flashcards
What is Hirschsprung’s disease?
Congenital absence of ganglia in a segment of the colon (rarely long segment disease all the way to the stomach). This causes functional GI obstruction, constipation and megacolon.
Usually present with failure or delay to pass meconium
What complications can occur as a result of Hirschsprung’s disease?
Perforation Bleeding Ulcers Enterocolitis Short gut syndrome
How should suspected Hirschsprung’s disease be investigated?
Faeces may be felt in the abdomen and PR exam will reveal a tight anal sphincter and explosive faecal and gas discharge.
Rectal suction biopsy of the aganglionic section. Staining for acetylcholinesterase positive nerve excess is more accurate. (full thickness rectal biopsy)
How should Hirschsprung’s disease be managed?
Initial management is bowel irrigation until diagnosis is confirmed
Removal of the aganglionic segment with or without a colostomy (anorectal pull through)
What are the 2 most important risk factors for Hirschsprng’s disease?
Male
Down’s syndrome
What is oesophageal atresia and trachea-oeopshageal fistula?
Spectrum of disorders but usually occurring together. Upper oesophagus ends in a blind sack and there is a connection between the trachea and lower oesophagus.
What clinical features are there for oeopshagela atresia and trachea-oesophageal fistula?
Polyhydramnios Small stomach Cough Airway obstruction Increased secretions Blowing bubbles Distended abdomen Cyanosis Aspiration Inability to pass NG tube with x-ray showing it coiled up in the oesophagus
How is oesophageal atresia and trachea-oesopahgeal fistula managed?
Stop feeding
Suck out oesophageal pouch
Primary surgical repair
But half will have other anomalies
What is a congenital diaphragmatic hernia?
Defect in the diaphragm allows the abdominal organs into the thoracic cavity impeding lung development
How is a diaphragmatic hernia diagnosed?
Diagnosis can be made antenatally by US or postnatally via CXR
What effect does a congenital diaphragmatic hernia have on the development of the lungs?
Causes impaired lung development hypoplasia and pulmonary hypertension
What features might suggest a congential diaphragmatic hernia?
Difficult resuscitation at birth
Respiratory distress
Bowel sounds in hemithorax
Can be associated with neural tube defects, trisomy 18 and some chromosome deletions
How is congenital diaphragmatic hernia managed?
Prenatal
Referral to tertiary centre for foetal surgery - Tracheal obstruction by balloon may encourage lung growth but can cause prematurity.
Postnatal
Insert large bore naso gastric tube when diagnosis suspected to keep all air out of the gut.
Ventilate and paralyse as soon as born then surgery should follow at an appropriate centre.
What are inguinal hernias?
Occurring due to patent processus vaginalis. Hernia implies bowel involvement. Hydrocele if only fluid from the peritoneal cavity is present.
When are interventions required on hydroceles?
Hydrocele usually sort themselves out and intervention should only occur if persistent to age of 2 or more.
What are the clinical features of inguinal hernias?
Bulge lateral to the pubic tubercle during crying
Occur in boys 5 times more than girls
Usually on the right but can be left or bilateral
Hydrocele present in 19%
How are inguinal hernias managed?
Surgical repair 6 by 2 rules <6weeks operate within 2 days <6months operate within 2 weeks <6years operate within 2 months
When should umbilical hernias be operated on?
Note umbilical hernia are common, complications are rare and usually resolve by ages 2-3. These should not be operated on until after 3 years of age if large and symptomatic or 5 years if asymptomatic and small.
What is an imperforate anus?
Covering over the anal canal meaning faeces can’t exit.
Babies usually have an associated fistula. In boys this is a posterior urethral fistula in girls this is a posterior fourchette fistula. Absence of a perineal fistula in boys suggests communication with the urethra and so colostomy will be required.
GU imaging should be done to look for other abnormalities.
Which syndrome is associated with imperforate anus?
Trisomy 21 commonly have imperforate anus without a fistula.
How do mid-gut malrotations usually present?
Commonly this presents with bilious vomiting due to the absent attachment of the small intestines’ mesentery causing mid gut volvulus or obstruction of the third part of the duodenum. Usually 3-7 days after birth, volvulus with compromised circulation may result in peritoneal signs and haemodynamic instability.
Clinical Features No meconium Abdominal pain Constipation Passage of blood indicates necrosis
How are mid-gut malrotations repaired?
Surgical repair - Ladd’s procedure
How are mid-gut malrotations diagnosed?
Upper GI contrast study – shows DJ flexure is more medially placed
USS shows abnormal orientation of SMA and SMV
What is a gastroschisis?
Paraumbilical defect with extrusion of abdominal contents. Usually diagnosed antenatally
What are the risk factors for a gastroschisis?
Many pregnancies
Young parents
New father
How is Gastroschisis managed?
Cover in clingfilm once born and keep baby warm hydrated and aim to surgically repair as soon as possible. May require a staged procedure involving a silo as the abdomen will be too small at first for everything to fit in.
TPN may be required for multiple weeks as it takes a while for function to return
What is an exomphalos?
Defect of the umbilical ring causing herniation of abdominal viscera covered in peritoneum. Small example may only contain Meckel’s diverticulum whilst larger may contain stomach, liver and bladder etc. Again abdominal cavity likely to be small and contents can’t fit.
How is Exaomphalos and Gastroschisis diagnosed?
Diagnosed antenatally via scan, AFP likely to be raised too.
How is Exomphalos managed?
Protect herniated viscera and keep baby warm hydrated, maintain electrolytes, prevent hypothermia. Aim to surgically repair as soon as possible. May require a staged procedure involving a silo as the abdomen will be too small at first for everything to fit in.
TPN may be required for multiple weeks as it takes a while for GI function to return
May lead to respiratory distress due to reduced volume of abdominal cavity.
What is Meckel’s diverticulum?
A congenital diverticulum of the small intestine. It is a remnant of the omphalomesenteric duct (also called the vitellointestinal duct) and contains ectopic ileal, gastric or pancreatic mucosa. Normally, in the foetus, there is an attachment between the vitellointestinal duct and the yolk sac. This disappears at 6 weeks gestation.
What are the rule of 2’s in Meckle’s diverticulum?
Rule of 2s
occurs in 2% of the population
• is 2 feet from the ileocaecal valve
• is 2 inches long
How does meckel’s diverticulum usually present?
Presentation (usually asymptomatic)
• abdominal pain mimicking appendicitis
• rectal bleeding
• Meckel’s diverticulum is the most common cause of painless massive GI bleeding requiring a transfusion in children between the ages of 1 and 2 years
• Intestinal obstruction – secondary to an omphalomesenteric band (most commonly), volvulus and intussusception
What is the management of meckel’s diverticulum?
Removal if narrow neck or symptomatic. Options are between wedge excision or formal small bowel resection and anastomosis.
What causes jejunal/ileal atresia
Occurs due to vascular insufficiency in utero 1 in 3000
How does jejunal/ileal atresia present?
Presents with obstruction and bilious vomiting in neonates usually within 24 hours of birth
How are Jejunal/ileal atresia diagnosed?
AXR shows air-fluid levels
How are jejunal/ileal atresia managed?
Surgery – laparotomy with primary resection and anastomosis
