Vomiting and Malabsorption in Children Flashcards
Physiology of vomiting - what are the stages of vomiting?
- Pre-ejection phase - Pallor, Nausea, Tachycardia
- Ejection Phase - Retch, Vomit
- Post-ejection Phase - child is lethargic, pale, sweaty, weakness, shivering
what are the triggers of vomiting?
GI triggers are enteric pathogens or food allergies which send impulses to vomiting centre through vagus nevre causing vomiting
Inner ear stimulus of the labyrinth occurs in motion sickness
Vomiting centre when stimulated triggers the chemoreceptor trigger zone dopamine and serotonin receptors. Eg chemotherapy triggers the muscarinic receptors in the vomiting centre The CTZ is outside the blood brain barrier. The labrynth sends the signals to the vestibular nuclei in the pons which contains histamine and muscarinic receptors during motion sicknesss, these send signals to CTZ which inturn sends message to vomiting centre in medulla oblongata
what is retching?
Retching involves a deep inspiration against a closed glottis. This, along with contraction of the abdomen, leads to a pressure difference between the abdominal and thoracic cavities. As a result, the stomach and gastric contents are displaced upwards toward the thoracic cavity.
what are the types of vomiting?
Effortless vomiting otherwise known as regurgitation
Haematemesis – blood in vomit – often seen in peptic ulcers or in portal hypertension
what causes vomiting in infants?
- GOR (most common)
- Cow’s milk allergy
- Infection
- Intestinal obstruction
what causes vomiting in children?
- Gastroenteritis
- Infection
- Appendicitis
- Intestinal obstruction
- Raised ICP
- Coeliac disease
what causes vomiting in young adults?
- Gastroenteritis
- Infection
- H.Pylori infection
- Appendicitis
- Raised ICP
- DKA
- Cyclical vomiting syndrome
- Bulimia
Case study:
6 week old baby boy
3 week history of vomiting after every feed
Bottle fed 6 ounces 3 hourly
Vomitus- large volume, milky or curdy, mostly projectile
Irritable and crying
Not gaining weight adequately
o/e looks slightly dehydrated
what are the differential diagnosis?
Gastroesophageal reflux (most common cuase)
Overfeeding (can occur but the volume is this case seems okay)
Pyloric stenosis
Cow’s milk protein allergy (can present as irritability and vomiting)
case continued:
Palpation of “olive” tumour (thickened pylorus)
Visible gastric peristalsis
Projectile non bilious vomiting
whats the diagnosis?
Pyloric Stenosis
Ultrasound appearance of pyloric stenosis with long, thickened muscle at pylorus
US show thickened pylorus which is classic of pylorus stenosis
what is Pyloric Stenosis, who does it occur in and what does it cause?
Babies 4-12 weeks
Boys > Girls
Projectile non-bilious vomiting
Weight loss
Dehydration +/- shock
Characteristic electrolyte disturbance:
- Metabolic alkalosis (↑pH)
- Hypochloraemia (↓Cl)
- Hypokalaemia (↓K)
how do you treat pyloric stenosis?
Fluid resuscitation (Fluid to correct metabolic alkalosis and dehydration)
Refer to surgeons- Ramstedt’s pyloromyotomy
what is Effortless Vomiting?
This is almost always due to gastro-oesophageal reflux
Very common problem in infants
Self limiting and resolves spontaneously in the vast majority of cases
A few exceptions: Cerebral palsy, Progressive neurological problems, Oesophageal atresia +/- TOF operated, Generalised GI motility problem
LOS and diaphragmatic crura prevent expulsion of gastric contents into the oesophagus
why does reflux occur in babies?
In babies the LOS is lax and also they are mainly placed in the lying posture, their feeds are liquid feeds mainly and all this predisposes them to GOR, this improved with age as solids are introduced at 6 months and with posture as when they are sitting or standing
what are the presenting symptoms?
Sandifer’s syndrome is the association of gastro-oesophageal reflux disease with spastic torticollis and dystonic body movements
what should be invovled in a medical assessment? (when diagnosing GOR)
History & examination often sufficient
Oesophageal pH study/impedance monitoring
Endoscopy
Radiological investigations:
- Video fluoroscopy
- Barium swallow
can GOR effect growth?
yes
Very rare
If you do see it then warrants further investigation
radiology - what are the aims of a barrium swallow and what are some problems?
Aims:
Dysmotility
Hiatus hernia
Reflux
Gastric emptying
strictures
Problems:
Aspiration
Inadequate contrast taken (NG tube)
how is a pH study done?
pH studies - pH sensor placed 5cm above LOS
Measure amount of times pH in oesophagus drops below 4
whenw ould you do a upper GI endoscopy?
General anaesthetic
Only if persistent symptoms, growth faltering, resistance to anti-reflux symptoms
what is Nissen Fundoplication?
a laparoscopic procedure performed for patients with gastroesophageal reflux disease
Fundus wrapped around the LOS
Children with cerebral palsy are more likely to have complications of bloat, dumping and retching after surgery
Successful surgery may unmask more generalised GI motility problems in the child
how do you differentiate between osmotic and secretory diarrhoea?
what are endoscopy findings of coeliac disease?
Coelic – oedema, erythematous mucosa, flattening of villi, dipping in folds
what are histological findings of coeliac disease?
Helps make diagnosis of coeliac disease
Coeliac blunting of villi with infiltration of lymphocytes in the lamina propria and crypt hyperplasia
