Upper GI tract Flashcards
At what vertebrae does the trachea start and end?
C5 and T4
Where does the diaphragm sit?
T10
What is Stage 0 of swallowing?
Oral Phase
- chewing and saliva prepare bolus
- both oesophageal sphincters constricted
What is Stage 1 of swallowing?
Pharyngeal Phase
- pharyngeal musculature guides bolus towards the oesophagus
- upper oesophageal sphincter opens reflexively
- lower oesophageal sphincter opens due to vasovagal reflex (receptive relaxation reflex)
What is Stage 2 of swallowing?
Upper Oesophageal Phase
- upper sphincter closes
- superior circular muscles contract while inferior rings dilate
- sequential contractions of longitudinal muscle
What is Stage 3 of swallowing?
Lower Oesophageal Phase
- lower sphincter closes as food passes through
How is oesophageal motility measured?
pressure measurements (manometry)
What is the approximate pressure measurement of peristaltic waves?
around 40mmHg
What is the lower oesophageal sphincter’s resting pressure?
around 20 mmHg
What is the approximate change in the oesophageal sphincter’s pressure during receptive relaxation?
decreases by <5mmHg
What is the lower oesophageal sphincter mediated by?
inhibitory noncholinergic nonadrenergic (NCNA) neurons of the myenteric plexus
What is the absence of a stricture caused by?
- abnormal oesophageal contraction (hyper-motility, hypo-motility, disordered co-ordination)
- failure of protective mechanisms for reflux (GORD)
What are the different types of dysphagia?
- solids or fluids
- intermittent or progressive
- precise or vague
What is important when someone is complaining of dysphagia?
localisation
cricopharyngeal sphincter or distal
What is odynophagia?
pain on swallowing
What is regurgitation?
return of oesophageal contents from above an obstruction (functional or mechanical)
What may cause mechanical regurgitation?
obstructions eg: tumours
What is reflux?
passive return of gastroduodenal contents to the mouth
What is the biological characteristics of Achalasia?
loss of ganglion cells in Aurebach’s myenteric plexus in the lower oesophageal sphincter wall, leading to decreased activity of inhibitory NCNA neurones.
What is Achalasia?
the absence of peristalsis, and impaired relaxation of the lower oesophageal sphincter
What causes primary achalasia?
unknown aetiology
What causes secondary achalasia?
diseases that cause similar oesophageal motor abnormalities
- Chagas’ Disease
- Protozoa Infection
- Anyloid/Sarcoma/Eosinophilic Oesophagitis
What happens in the development of Achalasia?
- increased resting pressure of the lower oesophageal sphincter
- receptive relaxation sets in too late, and is too weak as the pressure in the LOS is much higher than the stomach, so food does not pass through
- swallowed food contents collects in the oesophagus causes increased pressure throughout with dilation of the oesophagus
- propagation of peristalic waves cease
What are the symptoms of Achalasia?
- weight loss
- dysplasia
- regurgitation
- oesophagitis
- pneumonia due to aspiration
Is Achalasia a disorder of hyper or hypomotility?
hypermotility
What is the course of Achalasia?
- insidious onset (symptoms for years before help)
- without treatment leads to progressive oesophageal dilation of the oesophagus
What does Achalasia predispose you to?
- increased risk of oesophageal cancer by 28-fold
What are the possible treatment options for Achalasia?
- Pneumatic Dilation
- Peroral Endoscopic Myotomy
surgery: - Heller’s Myotomy and then, Dor fundoplication
What is pneumatic dilation?
- weakening of the LOS by circumferential stretching and in some cases - tearing muscle fibres
What is the efficacy of pneumatic dilation?
71-90% respond initially, many subsequently relapse
What is Heller’s Myotomy?
a continuous myotomy performed for 6cm of the oesophagus and 3cm of the stomach
What is Dor Fundoplication?
anterior fundus folded over the oesophagus and sutured to the right side of myotomy
What are the risks associated with Heller’s Myotomy and Dor Fundoplication?
- oesophageal and gastric perforation (10-16%)
- splenic injury (1-5%)
- division of the vagus nerve (rare)
What happens in a Peroral Endoscopic Myotomy?
- mucosal incision
- creation of submucosal tunnel
- myotomy
- closure of mucosal incision
What is Scleroderma?
autoimmune disease that is usually irreversible
What are the biological effects of Scleroderma?
- hypo-motility in it’s early stages due to neuronal defects leading to atrophy of the smooth muscle of the oesophagus
- peristalsis in the distal portion ultimately ceases
- decreased resting pressure on the LOS
- GORD develops
What is Scleroderma associated with?
CREST syndrome
What is CREST syndrome?
- Calcinosis
- Reynauds phenomenon
- Esophageal Dysmotility
- Sclerodactyly
- Telangiectasia
How do you treat Scleroderma?
- exclude organic obstruction (no malignancy)
- improve force of peristalsis with prokinetics (cisapride) - low efficacy
- once peristaltic failure occurs, usually irreversible
What is corkscrew oesophagus?
diffuse oesophageal spasm
- inco-ordinate contractions
- marked hypertrophy of circular muscle
- pressures of 400-500mmHg
What symptoms can corkscrew oesophagus present with?
- dysphagia
- chest pain
What is the treatment of corkscrew oesophagus?
may respond to forceful pneumatic dilation - results are not as predictable
What vascular abnormalities cause dysphagia?
- dysphagia lusoria
- double aortic arch
Where do oesophageal perforations tend to occur?
- Cricopharyngeal constriction
- Aortic and bronchial constriction
- Diaphragmatic and ‘sphincter’ constriction
What can cause oesophageal perforations?
- Iatrogenic (investigation caused) >50%
- Spontaneous 15%
- Foreign body 12%
- Trauma 9%
- Intraoperative 2%
- Malignant 1%
When do Iatrogenic oesophageal perforations tend to occur?
- usually at OGD
- more common: diverticula, cancer
What can cause an Iatrogenic Oesophageal perforations?
- OGD 0.03%
- Stricture dilation 0.1-2%
- Slcerotherapy 1-5%
- Achlasia dilation 2-6%
What tends to cause spontaneous oesophageal perforations?
Boerhaave’s
What happens in a spontanous (Boerhaave’s) oesophageal perforation?
- sudden increase in intra-oesophageal pressure with negative intra thoracic pressure
- vomiting against a closed glottis
- tends to happen at the left posterolateral aspect of the distal oesophagus
What common foreign bodies tend to cause a oesophageal perforation?
- disk batteries (electrical burns if impacts in the mucosa)
- magnets
- sharp objects
- dishwasher tablets
- acid/alkali
What can cause a trauma induced oesophageal perforation?
- NECK penetrating trauma
- THORAX blunt force (very rare)
How do trauma induced oesophageal perforations present?
- Dysphagia
- Blood in saliva
- Haematemesis
- Surgical empysema
How does a surgical empysema present?
air under the skin
crackling sensation on touch
What can cause a intraoperative oesophageal perforation?
- Hiatus hernia repair
- Heller’s cardiomyotomy
- Pulmonary surgery
- Thyroid surgery
What tends to cause malignant oesophageal perforations?
advanced cancers
What can be used to treat an oesophageal perforation?
- radiotherapy
- stenting
- dilation
What is the prognosis for a malignant oesophageal perforation?
poor
How do oesophageal perforations present?
- pain (95%)
- fever (80%)
- dysphagia (70%)
- emphysema (35%)
What investigations would you run on a suspected oesophageal perforation?
- chest x-ray
- CT
- swallow test (gastrograffin)
- OGD
What is the initial management plan for a oesophageal perforation?
- nil by mouth
- IV fluids
- broadspectrum ABx and antifungals
- ITU/HDU care
- Bloods (incl. G+S)
- tertiary referral centre