GIT + WRAP UP Flashcards
What is the pathogenesis of pyloric stenosis?
Circular fibres at the junction thicken and hypertrophy –> excess thickening –> bulky, hypertonic pylorus –> outflow obstruction
What are the clinical features of pyloric stenosis?
Projectile vomiting after food More common in boys, peak age 6wks FHx Still hungry, wanting to feed Not unwell EXAM - palpable pylorus at RUQ 'olive' - visible peristalsis/distension - dehydrated
What investigations should be performed in a child with pyloric stenosis?
U/S - elongated and thick pylorus ‘cervix sign’ as it distends stomach (best taken after a feed - distends stomach)
- Dehydration, hypochloraemia (loss of acid), hypokalaemia (H loss, push K into cells), alkalosis
How do you manage pyloric stenosis?
Cease oral feeds
Rehydrate IV - NS + 5% glucose + with 20mmol/L KCl
+/- NGT to drain stomach
Paed surgery consult - Ramstedt’s pyloromyotomy
How does a transoesophageal fistula present?
Difficulty feeding with coughing and choking
Baby coughs and goes blue
Respiratory distress, produces copious frothy white mucus
TOF cough due to floppy larynx
Tympanic LUQ from air in stomach
Gastric tube could not be inserted
Polyhydramnios, small for gestational age, maternal age
How do you investigate TOF? Treatment?
X-ray - darker shadow showing blind end of oesophagus, stomach is distended from air (via trachea of TOF)
Rx: stop oral feeds, IV fluids etc.
- Paed surgery consult - either join together if long enough or distend a bit first before attaching/use goretex or other pieces of GIT to join
Describe the differences in mild, moderate, severe dehydration
MILD (3%) - thirsty, decreased urine output, dry MM, mildly tachy
MOD (5%) - sunken eyes/fontanelles, mod tachy, lethargic, increased RR, skin turgor
SEVERE (10%) = SHOCKED - altered LOC, cool peripheries, mottled, slow cap refill
What is the rehydration protocol for mild/moderate/severe dehydration?
Mild: oral fluids if tolerating, admit if inadequate (0.5mL/kg ever 5 minutes), consider parenteral rehydration
Moderate: 4 options:
- Aggressive and diligent oral
- Rapid NG rehydration (gastrolyte) 10mL/kg/hr for 4hrs
- Rapid IV rehydration NS + 5% glucose 10mL/kg/hr for 4hrs
- Standard IV rehydration (maintenance + replace dehydration)
Severe: oxygen, use IO route if IV not accessible
give 20mL/kg bolus NS, repeat until signs of shock are reversed
- Give oxygen
- Get a UEC, BGL
What are the key clinical features of intussusception?
Peak incidence 6-9mo 1. Colicky abdo pain (draw legs up) 2. Vomiting 3. Abdominal mass 4. Red currant jelly stool (blood and mucus) U/S - target sign recent viral illness
What is a volvulus and how does a volvulus present?
Malrotation of intestine - twisting of bowel and supporting mesentery causing ischaemia
- Previously well
- Bilious vomiting
- Abdo pain
- Taut, tender sometimes distended abdo
- High pitched or no bowel sounds
What are some other differentials for vomiting in a child?
Bowel obstruction Intussusception Volvulus Pyloric stenosis Gastroenteritis Acute appendicitis GORD Oesophagitis TOF
How will a bowel obstruction present in a child?
Blood/bile in vomit
Abdo distension
No poo
What is the most common cause of diarrhoea in a child?
Viral gastroenteritis
- Rotavirus, adenovirus
Bacterial: E.coli, campylobacter, salmonella, shigella
Protozoa: Giardia, cryptosporidium
What are some causes of bloody diarrhoea?
Intussusception
Paediatric IBD
Infection
HUS
What is the triad of symptoms for HUS?
- Microangiopathic haemolytic anaemia
- Thrombocytopaenia
- AKI
How will a malabsorption diarrhoea present?
Fat: steatorrhoea, pale, bulky, foul smelling stools
Carbohydrate: frequent watery diarrhoea
FTT, weight loss, abdo distension, abdo pain, excoriated anus from acidic stool
How does paediatric Crohn’s disease present?
Blood, mucopurulent diarrhoea
Abdo pain and cramping
Decreased growth and weight
Anorexia
How do you calculate maintenance fluids for a child?
4:2:1 per hour
How do you classify neonatal jaundice?
<24 hours = always pathological
- Haemolysis (Rhesus, ABO incompatibility, G6PD, PKU, haematoma, hereditary spherocytosis)
- Infection
24hrs - 2 weeks
- NORMAL - physiological, Breast feeding (lack of input), breast milk, Gilbert’s or Crigler Najaar
> 2 weeks
- Biliary atresia, Congenital hypothyroidism (should find on Guthrie), neonatal hepatitis,, breast milk (inhibits enzyme that conjugates bili)
What is breastfeeding jaundice?
Inadequate breastfeeding = inadequate intake –> not enough bowel movements to remove bili from the blood –> increased enterohepatic circulation –> increased bili reabsorption from intestines
How is intussusception treated?
Fluid resuscitation
NGT if bowel obstruction
Air or barium enema: injected into colon –> X-ray fluoroscopy to watch air/contrast material flow into the large intestine –> creates pressure within the large intestine and “un-telescopes” intussusception –> relieving the obstruction
- If unsuccessful will need surgical reduction
- Surgery straight away if perforation
Sometimes give prophylactic antibiotics for risk of perforation with enema
What are the clinical features required to make a diagnosis of gastroenteritis?
Needs to have vomiting AND diarrhoea AND fever
What are the common causative organisms of gastroenteritis in children?
Norovirus, adenovirus
Rotavirus becoming less common because of the vaccination
Salmonella, campylobacter, E.coli
What are some differential diagnoses for gastro?
Acute appendicitis Mesenteric adenitis UTI Sepsis - meningitis Intussusception Malrotation Coeliac disease Lactose intolerance IBD Sepsis Vomiting - meningitis
What are the principles of fluid rehydration in children?
Fluid deficit (mL) = wt (kg) x percent (%) dehydration x 10 e.g. 20kg = 20 x 5 x 10 = 1000mL Maintenance (4:2:1 rule x 10mL per kg) Replace ongoing losses (ADD TO THE VOLUME GIVEN DAILY)- For upper GIT losses use 0.9% NS + 5% glucose + KCl 20mmol/1000mL
Why are babies at high risk of jaundice?
Cephalohaematoma from birth trauma - haemolysis
Immature GIT - needs milk to stimulate enterohepatic circulation
Immature liver
Higher Hb levels - foetal Hb has shorter half life
How do you treat neonatal jaundice?
Phototherapy - monitor 4-6hourly, then 8-12hrly
Exchange transfusion if severe, symptomatic (lethargy, hypotonia, poor sucking, or high-pitched cry), or not responding to phototherapy
What is the most common cause of appendicitis?
Faecoliths obstructing the lumen
What are some differentials for appendicitis?
Mesenteric adenitis Acute gastroenteritis IBD UTI Intussusception Malrotation Coeliac disease Meckel's diverticulum Gynae in girls
What investigations are required for appendicitis?
FBC and CRP
U/S is not usually helpful
CT more accurate but radiation
What are the management options for appendicitis?
Active observation on admission- may spontaneously resolve
Conservative - broad spectrum antibiotics
Percutaneous drainage
Appendicectomy
What usually causes intussusception and where does it usually occur?
In children there is usually no lead point
- Usually occurs after a viral illness –> lymphatic congestion + inflammation of Peyer’s patches –> obstruction –> necrosis and perforation
Ileocolic location
Pathological lead points: Meckel’s diverticulu, HSP, small bowel lymphoma
What investigations are required for intussusception?
Abdominal x-ray - look for perforation
Ultrasound - target sign, pseudokidney sign
Stool sample for occult blood
Air enema - diagnostic and therapeutic
What is the management for intussusception?
Fluid resusc +
Analgesia
Air enema (if haemodynamically stable and no evidence of perforation)
Surgical (if enema fails or signs of perf or signs of necrotic bowel (e.g. red currant jelly))
What are some investigations for volvulus?
Abdominal x-ray looking for caecum
Upper GIT contrast study - corkscrew tapering
Contrast enema
Abdominal ultrasound
What kind of biochemical changes occur with pyloric stenosis?
Hypochloraemic hyperkalaemic metabolic alkalosis
What is necrotising enterocolitis and how does it present?
- Portions of bowel undergo necrosis postnatally
- Mostly seen in premature babies
- Unknown cause, could be due to hypoxia at birth, OR premmy babies who have poor digestion, immune systems, poor circulation
Features: Feeding intolerance, bloody stools from intestinal necrosis and haemorrhage, abdominal distension, and peritonitis due to perforation
Treat: fluid resusc, TPN, broad spec Abx
What is a congenital diaphragmatic hernia and how does it present?
Defect in foetal diaphragm allowing abdominal contents to protrude into the thoracic cavity
Severe respiratory distress at birth due to pulmonary hypoplasia and pulmonary hypotension
Why does congenital diaphragmatic hernia have such a high mortality?
Presence of abdominal organs in the chest cavity –> inadequate lung development –> pulmonary hypoplasia and pulmonary hypotension –> severe respiratory distress
How does a TOF develop?
Failure of correct division of tracheal primordium from oesophagus during early embryological development
What is the difference between gastrochisis and omphalocele?
Gastrochisis - abdominal contents are present outside abdomen WITHOUT a covering membrane, due to defect in anterior abdominal wall
Omphalocele - herniated bowel etc, enclosed in a membranous sac, due to issue with the umbilical cord
What maternal condition is associated with TOF?
Polyhydramnios
What is the management for a volvulus?
Fluid resusc
NGT NBM
Broad spec Abx if suspect necrosis
Urgent surgery
What investigations do you do for neonatal jaundice?
Serum bili - repeat 4-6hourly
Bili check across forehead (BiliCheck)
FBC and group
Coombs
How do you calculate replacement of deficit of fluids?
Weight (kg) * percent deficit (e.g. 5) * 10
What fluids can be used for oral rehydration?
- Babies who are breastfed should receive small frequent breastfeeds, can be supplemented with an ORS
- For all other children, offer an ORS
- If an ORS is unavailable, or refused, dilute juice/lemonade (mixed as 1 part
juice/lemonade with 4 parts water) can be used only if a child does not
have any clinical signs of dehydration
How do you ensure that the NG tube is in the stomach?
Aspirate the fluid and check acidity using litmus tape
What signs need to be assessed during rehydration of a child?
Reassess at 4-6hrs, then 8hrly afterwards
- weight change
- clinical signs of dehydration
- urine output
- ongoing losses
- signs of fluid overload, such as puffy face and extremities
Why does pyloric stenosis give hypokalaemia?
Metabolic alkalosis from vomiting HCl - body desires more H+ ions - swaps them for K+ - hypokalaemia
