Gastro N-Z Flashcards
What is the definition and epidemiology of Necrotising enterocolitis NEC?
Severe gastrointestinal disease characterized by massive epithelial destruction leading to intestinal barrier failure.
0.5% births.
What is the aetiology of Necrotising enterocolitis NEC?
Unknown, likely multifactorial. Hypothesis: immature intestinal battier and mucosal immune system -> bacterial translocation and epithelial inflammation. Localised injury leads to increased infiltration in that area leading to more infection and more inflammation -> further damage.
Eventually, intestinal necrosis and sepsis.
Bell’s classification I (suspect, non septic signs) II (definite, blood investigation and XR changes), III (advanced shock, peritonitis or pneumoperitoneum)
Associated with prematurity, low BW, formula feeding, stress, bacterial colonization. UVA/C insertion, CHD, maternal cocaine nuse, RDS.
What are the history and exam findings of Necrotising enterocolitis NEC?
Stage I: temperature instability, bradycardia, aopnea, lethargy, poor feeding, bilious aspirates, GI bleeding, ileus on XR.
StageII: + metabolic acidosis, thrombocytopenia, GI bleeding, tender abdomen, wall erythema, mass, AXR signs
Stage III: + shock, marked peritonitis, abdominal distension, neutropenia, DIC, ionotropic support, pneumoperitoneum on AXR.
What investigations would you do for Necrotising enterocolitis NEC?
Bloods: depend on stage, but usually low Hb, high WCC, metabolic acidosis and electrolyte imbalances
AXR: Football sign of air collecting in anterior abdomen when supine, may see fxed dialted loops of bowel, outlined falciform ligament, pneumoperitoneum.
USS: operator dependent, may see intramural gas.
What is the management of Necrotising enterocolitis NEC?
Conservative: Stages I/II, NBM, IV feed and fluids, NGT decompression, IV Abx, Blood/platelet transfusion and electrolyte monitoring.
Surgical: failure of conservative management, Laparotomy via supraumbilical transverse incision with resection of necrosed bowel and formation of stoma/mucous fistula.
What are the complications and prognosis of Necrotising enterocolitis NEC?
Stricture, fistula, recurrence, short gut syndrome, malabsorption, TPN associated cholethiasis.
20-40% of NEC require surgery. Mortality 50%.
What is Neonatal jaundice?
Excess bilirubin leading to yellow discoloration of skin and sclera.
What is the background of Neonatal jaundice?
50% of neonates to different degrees.
Unconjugated (pre hepatic)
· Physiological
o Unstable fetal Hb: high turnover
o Defective BR metabolism: low hepatic metabolism in neonates.
o Defective excretion: underdeveloped gut flora.
o Breast milk jaundice: 2nd week to 3rd month, due to UPDGR inhibition
· Pathological
o Haemolytic
§ AIHA
§ HDN
§ Hereditary spherocytosis, G6PD
§ Congenital infection, bacterial sepsis.
o Non-haemolytic
§ High Hb load: haemorrage or polycythaemia
§ Galactosaemia and hypothyroidism
Conjugated (hepatic / post hepatic)
· Neonatal hepatitis: TPN related, congenital infection, a1ATD, CF.
· Bile duct obstruction: biliary atresia, coledochal cyst
What is the history and exam findings of Neonatal jaundice?
General: May be asymptomatic (phys) or unwell (poor feeding, vomiting, fevers confusion, seizures, behavioral etc)
Age of onset: <24h pathological, >24h probably physiological, >2/52 breast milk
Clinical jaundice starts at BR level 80-120 umol/l. Look in sclera.
What investigations would you use for Neonatal jaundice?
Early(<24h): FBc, film, maternal/infant ABO, maternal TORCH screen, DAT
> 24h: Blood + film, examine
Persistent (>2wk) Total serum BR and conj/unconj fraction. Then bloods or USS.
Conjugated: requires urgent investigation, USS biliary tree of biopsy isotope scanning.
What is the management of Neonatal jaundice?
General: tx cause if present.
Tx jaundice: prevent bilirubin encephalopathy (kernicterus)
Phototherapy: Place neuonate under 450nm wavelength lights on warm bed. Converts stereoisomer rendering it soluble and leading to renal excretion.
Exchange transfusion: if intensive phototherapy fails, or extreme cases. Must have hearing screening.
What is the complications and prognosis of Neonatal jaundice?
BR has neurotoxic effects: seizures, cerebral palsy, sensorineural deafness, LDs.
Good if physiological, spontaneous resolvement.
What is Oesophageal atresia / trachea esophageal fistulae?
Congenital malformation of the oesophagus leading to loss of continuity in the lumen, leading to an upper or lower oesophageal pouch. TOFs are abnormal communication between oesophagus and trachea and are related to OA.
What is the background of Oesophageal atresia / trachea esophageal fistulae?
1/4500.
General: Aetiology unclear. Spritx classification involves judgement of presence/absence of cardiac abnormalities and low BW extent.
Classification:
· Proximal OA with distal/proximal TOF (or both)
· Isolated OA
· H type TOF without OA
Associated with VACTERL (vertebral, anorectal, cardiac, tracheal, oesophageal, renal, limb) / CHARGE (coloboma, heart defects, atresia choanal, retarded G&D, genital hypoplasia, ear deformities). SCHISIS (Exhomphalos, cleft lip and palate, genital hypoplasia). Potter syndrome (bilateral renal agenesis) and Trisomy 18.
What is the history and exam findings of Oesophageal atresia / trachea esophageal fistulae?
Prenatal: polyhydramnios due to intestinal obstruction. Small or absent stomach bubble in scan.
Postnatal: all infants with hx of polyhydramnios should have NG tube passed at birth. May present with coughing and choking at first feed.
Abdominal distension in TOF, or scaphoid abdomen. Examine other anomalies.
What investigations would you use for Oesophageal atresia / trachea esophageal fistulae?
Plain XR: CXR confirms dx with coiled NGT in upper pouch. Distal bowel gas shows distal TOF.
Specific: ECHO for other abnormalities.
What is the management of Oesophageal atresia / trachea esophageal fistulae?
Initial: immediate transfer to neonatal surgical centre. Head up and prone, preventing regurgitation. Suciton and irrigation to upper pouch. NBM.
Surgical: (short gap) Single stage correction with anastomosis of upper and lower ends with TOF ligation. Chest drain may be left at anastomotic site.
Surgical (long gap): Placement of Peg and ligation of TOF then allow child growth. Secondary surgery with oesophageal replacement with gastric transposition. Thoracotomy or thoracoscopic.
What is the complications and prognosis of Oesophageal atresia / trachea esophageal fistulae?
Surgical: anastomosis leak, dysmotility, GORD, strictures, recurrence of fistula. Tracheomalacia, failure to thrive and other complicaitons too
Survival rates 90%. RF are low BW, and other abnormalities. Long gap OA require the most operations.
What is Pyloric stenosis?
Hypertrophy and hyperplasia of the pyloric sphincter muscle leading to gastric outflow obstruction. AKA HPF.
What is the background of Pyloric stenosis?
1-500 live births.
Multifactorial – genetic and environmental. May be due to deficiency of NOS containing neurons at pylorus, abnormal innervation, hypergastrinaemia, hyperacidity.
Due to hypertrophy or hyperplasia of the clls in the circular/longitudinal muscle wall muscles in gastric pylorus.
What is the history and exam findings of Pyloric stenosis?
Presents at 2-6/52, with progressive non bilious projectile vomiting after prolonged feeds, which can be projectile. May have coffeeground vomiting from Mallory Weiss tear.
Persistently hungry after vomit, constipated, failure to thrive.
Systemic: weight loss, dehydration, CRT high , low skin turgor, sunken fontanelle, low urine output.
GI: visible peristalsis from left to right LUQ during feed, Palpation of pyloris feels like olive mass and aided by use of test feed.
What investigations would you use for Pyloric stenosis?
Bloods: ABG shows classic: low K, metabolic alkalosis, hypochloraemia.
USS abdomen used to aid diagnois. Pyloric muscle parameter of >4mm
What is the management of Pyloric stenosis?
Preoperative: electrolyte imbalance correction.
Operation: Ramstedt pyloromyotomy – longitudinal incision through serosa with splitting of sphincter muscle. Can be supraumbilical incision or laporoscopic.
What is the complications and prognosis of Pyloric stenosis?
Recurrence uncommon, <1% morbidity.
Post operative vomiting common but settles in 25h. .
