What are some symptoms of gastrointestinal diseases?
Abdominal pain
Dysphagia
Heartburn
Dyspepsia
Flatulence
Vomiting
Constipation
Diarrhoea
Steatorrhoea
What is dysphagia?
Difficulty swallowing
What is heartburn?
Retrosternal burning discomfort which spreads up towards the throat & is a common symptom of acid reflux
Pain can sometimes be difficult to differentiate from IHD but a careful history will differentiate between the two
What is dyspepsia?
It describes a range of symptoms referable to the upper GI tract (e.g. nausea, heartburn, acidity, pain, distension) but patients are more likely to use the term 'indigestion' for these symptoms
What is flatulence?
Flatulence describes excessive wind, presenting as belching, abdominal distention & passage of flatus per rectum
What is vomiting?
Vomiting occurs as a result of stimulation of the vomiting centres in the lateral reticular formation of the medulla
What might vomiting specifically result from?
Stimulation of the chemoreceptor trigger zones in the floor of the fourth ventricle or from vagal afferents from the gut
What is constipation?
Infrequent passage of stool (<twice weekly) or difficult passage of hard stools
What is diarrhoea?
Passage of increased amounts of loose stool (stool weight> 250g/24hr)
This must be differentiated from the frequent passage of small amounts of stool (which patients often refer to as diarrhoea), which is often seen in functional bowel disorders
What is steatorrhoea?
Passage of pale bulky stools that contain fat (>18mmol/24hr) & indicates fat malabsorptions a result of small bowel, pancreatic or biliary disease
The stools often float because of increased air content & are difficult to flush away
What does the upper digestive tract look like?
Learn to redraw this
What is the oesophagus?
Musculotendinous tube connecting the pharynx to the stomach
Where does the oesophagus pass through?
Through the chest via the mediastinum & lies posterior to the trachea
What are some symptoms of oesophageal problems and what are the important diseases to consider?
Dysphagia, pain, cough or vomiting
Important diseases to consider:
Pharyngeal pouchAchalasia- muscles of the lower part of the oesophagus fail to relax.Oesophageal spasm -painful contractionsOesophageal web- Thin membranes that grow across the inside of the upper part of the esophagusPeptic ulcer disease/refluxCarcinoma
How many overlapping constrictor muscles does the pharynx have and what are they called?
3 overlapping constrictor muscles :
superior, middle, inferior
What is a potential weakness in the structure of the pharynx?
Killian's dehiscence-the meeting point of 2 parts of inferior constrictor:
thyropharyngeus & cricopharyngeus
What is Zenker's diverticulum?
Out pouching of the posterior hypopharynx that causes regurgitation of undigested food several hours after eating
How might a posterior mucosal herniation take place?
During swallowing, the thyropharyngeus is propulsive & the cricopharyngeus is sphincteric
If the cricopharyngeus fails to relax at the right time, a posterior mucosal herniation may take place via Killian's dehiscence
Describe the histology of the oesophagus.
It has an outer longitudinal muscle coat & an inner circular muscle coat
Upper2/3 of oesophagus = striated muscle
Lower2/3 of oesophagus = non-striated muscle
So the middle 1/3 is mixed
Where does the motor & sensory nerve innervation come from for the oesophagus?
It's derived from thevagus (X) nerveforming something called theoesophageal plexus
(plexus of nerves within the muscle wall of the oesophagus, controlling its function & regulating its activity, & also coordinating peristalsis)
Where does the nerve plexus lie in the oesophagus?
Between outer longitudinal & inner circular muscle planes & also submucosally
2. Triggers peristaltic wave = pushes food bolus to the stomach.
3. Wave progresses by reflex activity at 2-4 seconds.
4. Stretching get causes depolarisation and action potential
5. This propagates and creates waves of muscle relaxation and contraction = peristalsis
What is the cardiac sphincter at the gastro-oesophageal junction?
It's not a clearly defined anatomical structure (can't see it in endoscopy) so it's described as physiological but it prevents reflux of gastric contents into oesophagus
Does the oesophagus have a temperature sense?
Yes, it's perceived as a dull pain
Is pain from the oesophagus well localised?
No, it's poorly localised & may also be confused with pain from other mediastinal structures e.g. the heart
What are some causes of dysphagia?
- A sensation of difficulty in swallowing
What is haematemesis?
Vomiting blood
What is haemoptysis?
Coughing up blood
What is a pharyngeal pouch?
A herniation of mucosa through a weakness in the pharyngeal constrictor muscles
The pouch hangs down due to gravity
What will the patient complain about if they have a pharyngeal pouch?
Dysphagia combined with swelling developing in the lower neck, usually left side
What are some potential complications of a pharyngeal pouch?
Undigested food may be regurgitated into the mouth hours after eating
Overflow into lungs may cause respiratory symptoms
What is the most common cause of oesophagitis?
GORD
What is candida oesophagitis?
Candida infection in oesophagus
What is achalasia (of the cardia)?
This refers to a condition where there has been a loss of ganglia from the intramural plexus, and therefore a failure of relaxation of the gastro-oesophageal sphincter.
This then leads to functional obstruction to oesophageal emptying with dysphagia for solids & liquids.
Failure of peristalsis leads to progressive dilatation of the oesophagus and retained oesophageal contents may be regurgitated, causing respiratory problems
What are possible treatments for achalasia?
Drugs e.g:
nifedipine (Ca channel blocker) to relax the sphincter
Balloon dilatation
Cardiomyotomy
What is an oesophageal spasm?
A descriptive term for spasm due to variety of causes leading to attacks of dysphagia & pain
What are some potential causes of oesophageal spasm?
Atypical achalasia
Gastro-oesophageal reflux
Motor disorders
Symptomatic peristalsis
Obstruction at the cardia
Neuromuscular disorders
What is a corkscrew oesophagus?
A classic manifestation of an oesophageal spasm
The pain can resemble reflux & heartburn and it should be managed with muscle relaxants
It is diagnosed by radiological appearance
What is an oesophageal web?
It's classically seen in middle-aged women and consists of:
glossitisiron deficiency anaemiadysphagiakoilonychia - spoon nails
Although rare, it is important as it ispremalignant