13- Paediatric surgery (2/2) Flashcards
pyloric stenosis background
- Progressive hypertrophy of pyloric muscle, causing gastric outlet obstruction
pyloric stenosis pathophysiology
Pathophysiology
- Aetiology unknown
- The pyloric sphincter is a ring of smooth muscle the forms the canal between the stomach and the duodenum.
- Hypertrophy (thickening) and therefore narrowing of the pylorus is called pyloric stenosis.
- This prevents food traveling from the stomach to the duodenum as normal.
- After feeding, there is increasingly powerful peristalsis in the stomach as it tries to push food into the duodenum.
- Eventually it becomes so powerful that it ejects the food into the oesophagus, out of the mouth and across the room- This is called “projectile vomiting”.
risk factors of pyloric stensosis
**- Male
- Family history
**
presentation of pyloric stenosis
- Presents in first few weeks of life (4-6 weeks)
- Failure to thrive : weightloss and dehydration
- Non-bilious projectile vomiting after feeds
pyloric stenosis on examination
o Peristalsis can be seen by observing abdomen
o Firm, round mass -> like a large olive (hypertrophic muscles of pylorus)
investigations for pyloric stenosis
- Abdominal US -.> thickened pylorus
- Blood gas- classic would be metabolic alkalosis (hypochloraemaic hypokalaemia)
why hypochloraemic hypoklaemia in PS
metabolic alkalosis as the baby is vomiting HCL from stomach
management of pyloric stenosis
- Rehydration to correct metabolic abnormalities
- Laparoscopic pyloromyotomy (Ramstedts operation)
o Incision is made in the smooth muscle of the pylorus to widen canal allowing food to pass from stomach to duodenum as normal - Excellent prognosis
Oesophageal atresia (OA) and trachea-oesophageal fistula (TOF) background
- Rare birth defect which occurs when the upper part of the oesophagus doesn’t connect with the lower oesophagus and stomach
- Usually ends in a pouch
- Means baby cant swallow safely, if at all
- Can develop complications such as chocking and pneumonia
- Trachea-oesophageal fistula
Can occur alongside oesophageal atresia.
Connects the lower part of the oesophagus with the trachea
risk factors for oesophageal atresia (OA)
- Babies who’s mother had polyhydramnios
- More common in babies who have development problems with their kidneys, heart and spine
- Trisomy 18 and 21
complications of oesophageal atresia
- Air passed from the windpipe to the oesophagus and stomach -> bowel perforation due to air in the stomach and bowel
- Stomach acid passes into the lungs
presentation of OA
Presentation
- May be suspected on antenatal US
- Cannot swallow and will drool copious amounts of salvia
- Aspiration of saliva or milk
o Aspiration pneumonitis
- Can lead to acute gastric perforation
- Vomiting
- Blue tinged skin while feeding
- Rounded abdomen
- Failure to thrive – air in stomach and bowels due to trachea-oesophageal fistula
investigations for OA
- Xray
- Bronchoscopy
- Oesophagoscopy
management of OA
- Will require operation in first few days of life to remove any connection between the oesophagus and trachea and have the two pouches of the oesophagus joined
- Nutrition will be IV
- Suction tube placed nasally to remove fluid from the pouch in oesophagus
signs of OA on X-ray
types of OA and trachea-oesophageal fistula (TOF)
biliary atresia background
- Congenital condition where section of bile duct is either narrowed or absent
pathophysiology of biliary atresia
- Lack of bile duct causes causes cholestasis
- Bile cannot be transported from the liver to the bowel
- Conjugated bilirubin excreted in bile, therefore biliary atresia prevention excretion of conjugated bilirubin
presentation of biliary atresia
Shortly after birth with
- Significant jaundice
- High conjugated bilirubin
- Suspect in babies with persistent jaundice >14 days in term babies and 21 days in prem babies
investigations for BA
Conjugated and unconjugated bilirubin
- High proportion of conjugated suggest liver is processing bilirubin for excretion (by conjugating it), but it is not able to be excreted into the bowel
Hepatic scintigraphy radioisorope scan: Fibrosis of biliary tree
This infant with prolonged jaundice, dark urine, chalky-white stool and conjugated hyperbilirubinaemia is suspicious for an obstructive cause of jaundice. The results of the hepatic scintigraphy radioisotope scan (highlights the liver and not the bowel) is suspicious for biliary atresia. Biliary atresia is characterized by progressive fibrosis and destruction of the biliary tree