Gastric Outlet Obstruction

Question 1

What is Gastric Outlet obstruction

Answer 1

The obstruction of the gastric outlet (at the level of the pyloric sphincter)

Question 2

What are the causes of gastric outlet obstruction

Answer 2

Benign:
Peptic Ulcer (most common) - Inflammation blocking or strictures
Gastric Polyp
Gastric TB
Gallstone (Bouveret Syndrome) - Cholecystoduodenal fistula allows passage of a gallstone into the duodenum, which can cause obstruction
Congenital Pyloric Stenosis in children
Pancreatic Pseudocyst – Can compress gastric outlet
Bezoar - Indigestible Mass in the GI system e.g. hair/cellulose
Strictures form inflammation or corrosives

Malignant Conditions:
Pancreatic Cancer (most common)
Ampulla of Vater Cancer
Duodenal Cancer
Cholangiocarcinoma
Gastric Cancer - Adenocarcinoma, Lymphoma, GI stromal Tumours

Question 3

What will you find in a history taking of Gastric Outlet Obstruction?

Answer 3

Symptoms:

Nausea and Vomiting - Non Bilious Vomit (Has only entered stomach) within 1 hour of meals

Question 4

What are the signs of gastric outlet obstruction?

Answer 4

End of the bed:
Underwieght
Wasting
Bruising - Malnutrition

Abdomen:
Dilated LUQ/Epigastric Mass that may be the dilated stomach
Ascites - Hypoalbuminea due to malnutrition

Legs:
Oedema- Hypoalbuminea due to malnutrition

Question 5

What are the complications of gastric outlet obstruction?

Answer 5

Aspiration
Malnutrition
Metabolic Alkalosis with Hyponatreamia and Hypokalaemia - Aldosterone secretion from kidney in resposne to dehydration leads to loss of more H+ and K+

Question 6

What investigations will you order in gastric outlet obstruction?

Answer 6

Bedside Tests:
Urine Dipstick - May show paradoxical high K+ and K+ a they are excrete by kidneys for Na+. May just show deficiency in those 3

Bloods:
FBC (Anaemia or WCC)
LFT's (Rule out mets)
ABG - Constant vomitting (Metabolic Alkalosis)
UnE - Electrolytes and dehydration

Special Tests:
13C Urea Breath test in suspected peptic ulcer

Imaging:
Endoscopy
Abdominal X-Ray

Question 7

What is the treatment of gastric outlet obstruction?

Answer 7

Resuscitation:
A-E approach
Get IV Access/Give O2 to maintain sats of 94+ /Attach 12 lead ECG
Assessment with AMPLE history and brief examination
Get help - Medical reg on call

Medical:
NGT to decompress stomach and clear food
Fix any malnutrition problems, TPN high calorie etc, B12, Folate
Fix Electrolyte imbalances

Peptic Ulcer
If the cause is acute
E.g. Inflammation and oedema are found to be the cause of the obstruction – continue medical treatment
If medical treatment has had no effect after 2/3 days consider a surgical approach

Malignancy
Surgical Treatment
In late stage or palliative cancers, need to weigh up QOL change vs Surgery risks
Consider endoscopically placed stents/endoscopic balloon therapy instead of a full surgical treatment in these cases