upper GI tract Flashcards
anatomical contributions to LOS
3/4cm distal oesophagus within abdomen
diaphragm surrounds LO
phrenoesophageal ligament
angle of His
stages of swallowing
4 (0-3) oral pharyngeal upper oesophageal lower oesophageal
how to determine motility of oesophagus
manometry
functional disorders of the oesophagus
Abnormal contractions: Hypermobility
Hypomobility
Disordered coordination
Failure of protective mechanisms: GORD
regurgitation vs reflux
return of oesophageal content from above an obstruction (functional or mechanical) (regurg)
passive return of gastroduodenal contents to the mouth (reflux)
achalasia hypermotility pathophysiology
Increasing rested pressure of LOS
Receptive relaxation sets in late and is too weak (during reflex phase pressure in LOS is much higher than stomach)
Swallowed food collects in oesophagus (Increases oesophageal pressure)
Dilatation of the oesophagus
Peristalsis ceases
What is the angle of his
Angle between distal oesophagus and the fundus
Compresses distal oesophagus from lateral to medial
What is the relaxation of the LOS mediated by
Mediated by inhibitory neurons of myenteric plexus
What causes Achalasia
Loss of ganglion cells in aurebach’s myenteric plexus in LOS wall
decreased inhibitory neuron activity (non-cholinergic, non-adrenergic)
What diseases is hypermotility seen in
Chagas disease Protozoa Amyloid Sarcoma Eosinophilic oesophagitis
disease course of achalasia
- insidious onset,
- enlarged oesophagus
- oesophageal cancer increased 28-fold
- aspiration pneumonia is a risk
treatment of achalasia
pneumatic dilation to stretch muscles of the LOS
SURGICAL - hellers myotomy, dor fundoplication
What is pneumatic dilatation
Weakens LOS by circumferential stretching and in some cases, tearing of its muscles fibres
may relapse
What is Heller’s myotomy
A continuous myotomy performed for 6cm on the oesophagus and 3 cm onto the stomach
What is dor fundoplication
anterior fundus folded over oesophagus and sutured to right side
what type of disease is scleroderma
autoimmune disease - hypomotility neuronal defects (atrophy of smooth muscle) peristalsis in the distal oesophagus stops
name for pain on swallowing
odynophagia
treatment of scleroderma
exclude organic obstruction first
- prokinetics
- can use pneumotatic dilatation
- usually irreversible - may have to have oesophagus removed
conditions causing disordered coordination
corkscrew oesophagus
What is scleroderma?
Autoimmune disease Hypomotility due to neuronal defects Atrophy of smooth muscle of oesophagus Peristalsis in the distal portion ceases Decreases LOS resting pressure GORD develops
corkscrew oesophagus treatment
forceful pneumatic dilation of cardia
Where are iatrogenic oeseophgeal perforations normally
cricopharyngeal constriction
where are the areas of oesophagus prone to perforation
cricopharyngeal constriction
aortic and bronchial constriction
diaphragmatic and sphincter constriction
What is Boerhaave’s
Sudden increase in intra-oesophageal pressure with negative intra thoracic pressure
Vomiting against a close glottis
usually left posterolateral aspect of distal oesophagus
what foreign bodies may cause oesophageal perforation
Disk batteries Magnets Sharp objects Dishwasher tablets Acid/Alkali
What operations can cause perforations
Hiatus hernia repair
Hellers cardiomyotomy
Pulmonary surgery
Thyroid surgery
signs of trauma causing oesophageal perforation
dysphagia
blood in saliva
haematemesis
surgical emphysema
investigations for perforated oesophagus
CXR
CT
swallow gastrograffin
OGD
presentation of oesophageal perforation
pain
fever
dysphagia
emphysema
what to avoid doing for a suspected oesophageal perforation
endoscopy
initial management of oesophageal perforation
nil by mouth IV fluids broad spectrum ABs ITU bloods taken transferral to tertiary care
management of oesophageal perforation
primary repair 1st line
oesophagectomy - definitive solution
conservatively - metal stent
3 mechanisms that protect against reflux
Volume clearance - oesophageal peristalsis reflex
pH clearance - saliva
Epithelium - barrier properties
What increases LOS pressure
Acetylcholine Alpha-adrenergic agonists Hormones Protein-rich food Histamine High intra-abdominal pressure INHIBITS REFLUX
what decreases LOS pressure and promotes reflux
acidic food
fats
NO
smoking
Why is sporadic reflux normal
Pressure on full stomach
Swallowing
Transient sphincter opening
What are sliding hiatus hernias
Portion of stomach herniated
Squeezes through diaphragm
What is a rolling hiatus hernia
Junction is in place and the stomach herniates alongside the oesophagus
How do you investigate GORD
OGD - to exclude cancer
or confirm oesophagitis, peptic stricture and barretts
Oesophageal manometry
24hr oesophageal pH recording
treatments for GORD
Lifestyle changes (weight loss, smoking, EtOH) PPIs
surgical treatments are available for GORD
Dilation peptic strictres
Laparascopic Nissen’s fundoplication
which is worse sliding or rolling hiatus hernia
rolling
risk of strangulation greater
What are the different types of gastritis
erosive and haemorrhagic
Nonerosive, chronic active gastritis
Atrophic (fundal gland) gastritis
Reactive gastritis
features of erosive and haemorrhagic gastritis
Numerous causes, NSAIDs, ischaemia, vasculitis, stress etc
Acute ulcer - gastric bleeding and perforation
What are the features of Nonerosive, chronic active gastritis
Antrum usually
Helicobacter pylori - treat with amoxcillin, clarithromyocin, pantoporzole for 7-14 days
features of Atrophic (fundal gland) gastritis
Fundus
Autoantibodies vs parts and products of parietal cells
Parietal cells atrophy
Decreased acid and IF secretion
methods of mucosal protection in stomach
Mucus film
HCO3- secretion
Epithelial barrier (tight junctions, strong apical membrane)
Mucosal blood perfusion (good blood supply can get rid of H+ quickly)
functions of stomach
breaks food into smaller particles
holds food, releases it at steady rate
kills parasites and bacteria
what is produced in the cardia and pyloric region
mucus
what is produced in the body and fundus
mucus
HCl pepsinogen
what is produced in the antrum
gastrin
stimulation of gastric secretion
ACh - vagal parasympathetic fibres
gastrin from G cells of antrum
histamine from ECL cells and mast cells
chemicals for inhibition of gastric secretion
secretin - small intestine
somatostatin
PGs, TGF-a + adenosine
mechanisms repairing epithelila defects in stomach
Migration
Gap closed by cell growth
Acute would healing
How does migration repair epithelium
Adjacent epithelial cells flatten to close gap
via sideward migration along BM
stages of epithelial repair and wound healing
migration - Adjacent epithelial cells flatten to close gap
via sideward migration along BM
gap closed by cell growth - Stimulated by EGF, TGF-α, IGF-1, GRP & gastrin
acute wound healing - BM destroyed - attraction of leukocytes &
macrophages; phagocytosis of necrotic cells;
angiogenesis; regeneration of ECM after repair
of BM. epithelial closure by restitution & cell division
How are ulcers formed
H. Pylori Increased gastric juice secretion Decreased bicarbonate secretion Decreased cell formation Decreased blood perfusion
primary medical treatment ulcer
PPI or H2 blocker Triple Rx (amoxicillin, clarithromycin, pantoprazole) for 7-14 days
indications for surgery for ulcers
Intractability (after medical therapy) Haemorrhage Obstruction Perforation Relative: continuous requirement of steroid therapy/NSAIDs
When would you opt for elective surgery for ulcers
Rare - most uncomplicated ulcers heal within 12 weeks
if not - change medication, observe additional 12 weeks
Check serum gastrin (antral G-cell hyperplasia or gastrinoma [Zollinger-Ellison syndrome])
OGD: biopsy all 4 quadrants of ulcer (rule out malignant ulcer) if refractory
how to distinguish mechanical from neurological cause of dysphagia
liquids and solids hard to swallow - likely neuro
solids difficult/painful alone or solids first and then slowly liquids got harder to swallow - likely mechanical
how to distinguish mechanical from neurological cause of dysphagia
liquids and solids hard to swallow - likely neuro
solids difficult/painful alone or solids first and then slowly liquids got harder to swallow - likely mechanical
what is riglers sign
free air under diaphragm/intraperitoneal air
most common site of perforation of duodenum
anterior/superior surface of first part of duodenum (D1)
where in the gut is most likely to perforate
duodenum - 10x more than stomach
what subsequent infection is likely after abdominal surgery
pneumonia
taking deep breaths after surgery is painful, so not filling with air
lungs fill with fluid, gets infected, get chest infection
what is an intraabdominal collection
fluid from lavage during surgery hasn’t been fully washed out
causes a collection of contaminated fluid, subsequent infection
what score is used for severity of pancreatitis
modified glasgow criteria
PANCREAS
modified glasgow criteria
pancreatitis scoring (PANCREAS) Po2 Age (>55) Neutrophil/WBC Calcium (low) Renal (urea increased) Enzymes AST, LDH Albumin low Sugar high
what are the indicators for severe pancreatitis
over 3 modified glasgow within 48hrs
or CRP over 200
principles of management of pancreatitis
ABC
Fluid resuscitation (iv fluids, monitoring) Analgesia Pancreatic rest (NJ feeding, TPN) Determine underlying cause go to HDU if severe
investigation for gallstones
ultrasound
then if issue persists, MRCP (not ERCP as is too invasive, too risky)
intervention for persistent pancreatitis due to gallstones
ERCP once confirmed by MRCP
what is murphys sign
cholecystitis - inflammation of gallbladder
palpation of right costal margin upon holding a deep breath elicits pain (hand comes into contact with gallbladder)
what structures need to be divided and removed for a laparoscopic cholecystectomy
cystic duct and cystic artery
investigation of suspected achalasia
oesophageal manometry
