STOMACH DUODEUNM Flashcards
effect secretin on gastrin
Secretin inhibits gastrium
careful, separate and stimulation test increase his gastrin with gastrinoma
stimulation of gastrin realease
gastric distention vagus input pH up amino acid Calcium
pathway of gastrin release
antrum G. cells release gastrin to
stimulate parietal cells to release HCL (and intrinsic factor)
what cells secrete intrinsic factor and where
parietal cells
careful, same cells that release gastrin
stomach
how is B12 resorbed
terminal ileum
with intrinsic factor from stomach and
treatment of perforated duodenal ulcer from chronic nonsteroidal anti-inflammatory use
omental patch
PPI and treatment of H. pylori postoperatively
Marjolin’s ulcer
Majors have scars and burns
squamous cell carcinoma chronic wound
Cameron’s ulcer
associated with hiatal hernia
lesser curve
mechanical trauma or ischemia and peptic injury
may require treatment of hiatal hernia for bleeding
curling ulcer
hot curling iron
gastric ulcer
Severe burn injury
Cushing ulcer
Cushing’s reflux
elevated intracranial pressure
marginal ulcer
margin of tissue not capable handling gastric secretion
gastro-J.
bypass
risk factors for afferent limb obstruction
long limb
Antecolic position
physiologic effects of chronic partial afferent limb obstruction
DEconjugated bile acid
bacterial overgrowth
decreased vitamin B12 absorption
treatment of efferent limb obstruction
surgical reduction
closure of internal defect
most common metabolic consultation after Roux-en-Y gastric bypass
dehydration - most common short-term
most common long term:
B12 deficiency
iron deficiency
Dumping syndrome - also relatively common
alkaline reflux cause, diagnosis
after Billroth II reconstruction
increased bile reflux
Symptoms of
biliary vomiting
Iron deficiency anemia
weight loss
diagnoses:
HIDA scan easily diagnostic demonstrating bili secretion into the stomach and even into the esophagus
upper endoscopy can also be performed with biopsies
mucosa is beefy-red friable with ulcerations
treatment:
Convert to Roux-en-Y
Roux limb lengthened to at least 40 cm.
where somatostatin released from, what cells
antrum of the stomach
D Cells
inhibits:
gastrin
bicarbonate secretion
metabolic syndrome
type 2 diabetes
Impaired glucose tolerance
Dyslipidemia
Hypertension
Associated with obesity-central
NOT associated with nonalcoholic steatohepatitis
best treatment for H. pylori
PPI
Amoxicillin or Clarithromycin or tetracycline
( careful, do not confuse with ampicillin)
AND
Flagyl
treatment of dumping syndrome after Billroth II
Small frequent meals with
high-protein and fat
octreotide
failed conservative management:
Jejunal pouch for reservoir
Long Roux-en-Y limb delayed emptying
mechanism of omeprazole
inhibition of H+/K+ ATPase
irreversible
most common locations of gastrointestinal stromal tumors
stomach 60-70% Small bowel 20- 25% ( more common JEJUNUM) ( careful, carcinoid is ileum) Colorectum 5% Esophagus 5%
treatment carcinoid of the stomach
this is rare-8%
The treatment for localized carcinoids is complete removal.
For small pedunculated lesions, this can be accomplished endoscopically. Larger lesions may require wedge resection or partial gastrectomy. Patients with multiple gastric carcinoids may require total gastrectomy. For patients with recurrent or metastatic disease, somatostatin analogues can be used to decrease the burden of disease and treat carcinoid syndrome.
Carcinoid tumors most common locations
appendix #1 45% - most common mass (careful, not most common malignancy-adenocarcinoma)
the small intestine #2 ileum 28% - most likely to cause carcinoid syndrome
rectum 16% - does not produce serotonin
stomach 2-8%
prognosis of carcinoid
location, size, depth of invasion, and growth pattern.
prognosis of gastrointestinal stromal tumor
tumor size and mitotic index.
workup of gastrointestinal stromal tumor
no Percutaneous core or intraoperative biopsy
yes endoscopic biopsy is okay
stimulation of secretin from the duodenum and its effect
Secretin “ secretes” bicarbonate
stimulated by: fat acid and duodenum bile (careful, paradoxical since acid stimulates)
( also careful, CCK stimulated secretin and and vice versa)
most important mediator of the secretion of water, bicarbonate, and other electrolytes into the duodenum
inhibited gastrin
stimulation of CCK and its effect
ipid, protein, and carbohydrates inside the duodenum
CCK by I cells present in the duodenal mucosa
main mediator of the secretion of pancreatic enzymes.
induces the release of pancreatic enzymes by acinar cells.
cause the release of acetylcholine, vasoactive intestinal peptide, and gastrin-releasing peptide,
CCK induces the relaxation of the sphincter of Oddi
percent acid suppression associated with truncal vagotomy
50%
Improved with antrectomy
Indications for truncal vagotomy
refractory type II ulcer and body of the stomach and duodenum
Type III ulcer in the pyloric channel within 3 cm of the pylorus - was caused by from hypersecretion of acid
complications of truncal vagotomy
loss of vagal tone
Empty LIQUIDS after because loss of repeat receptive relaxation
solids moved more slowly-loss of churning
postoperative diarrhea usually improves in a few months
Which vagus nerve is more difficult to find
PR
posterior right
best initial screening test for H. pylori
serology testing for IgG
careful, best test for eradication is urea breath test
which testes for H. pylori if patient needs endoscopy for concern of brisk bleeding or perforation on initial evaluation
Rapid urease assay-single can be achieved with scope
describe helicalbacter pylori organism
gram-negative
Spiral
Motile
mechanism action of erythromycin
binds motilin receptors on smooth muscle cells
prokinetic agent decide erythromycin
metoclopramide
dopamine antagonist
stimulates acetylcholine release
management of recurrent ulcers after parietal cell vagotomy
PPI
hormone responses to acid in the duodenum
somatostatin increased from D cells to put the breaks on
GIP increased to dcr acid secretion and stimulate insulin
secretary and increased to inhibit gastrium and stimulated bicarbonate secretion
motility and is activated and to aid in gastrointestinal motility
best test to evaluate for delayed gastric emptying and diabetes - and normal times
nuclear medicine gastric emptying study
scintigraphy
Transit time of fried-egg sandwich with sulfur colloid
thought half-life 60-105 minutes
liquid half-life 10-45 minutes
how long may a MALT lymphoma need treatment this the results
remission gently achieved within 12 months
Relapse 10%
alternative H. pylori treatment regimens
omeprazole or lansoprazole, clarithromycin, and amoxicillin
omeprazole or lansoprazole, metronidazole, and clarithromycin
omeprazole or lansoprazole, bismuth, metronidazole, and tetracycline.
surveillance needed for MALT
After treatment:
2 months post treatment endoscopy Surveillance and biopsies
then every 6 months for 2 years
management of rebleed after endoscopic clipping and epinephrine injection of duodenal ulcer
rescoped!
75% of excess in repeat endoscopy
if fails: This emergency surgery
described used to check for bleeding gastroduodenal artery duodenal ulcer
superior inferior and MEDIAL
treatment of MALT gastric lymphoma who are H. pylori negative
chemoradiation
And
Radiation
risk factors for gastric cancer
diet
Gastric polyps!:
ALL Adenomatous polyp - Including tubular!
Hyperplastic polyps are benign but presents may often be due to chronic gastritis which is a risk factor
Type a blood Smoking Previous gastric surgery - including bypass Nitrates Previous H. pylori infection
risk of bleeding with gastric ulcer
highest- visible vessel - even of nonbleeding
active bleeding
intermediate-adherent clot
low-ulceration with black spot
of clean base
gastrin stimulates
gastric acid
Pepsinogen secretion
Mucosal growth
where is gastrin released
BOTH
Antrum and duodenum
from G. cells
what stimulates gastrin release
meal / food protein Antral distention Vagus AND Adrenergic-epinephrine! (Careful) gastrin releasing peptide
waht inhibits gastrin
passage and the lumen
Somatostatin
risk with prolonged hypergastrinemia
mucosal hyperplasia
Increased number of:
Enterochromaffin-like cells
associated development of gastric carcinoid tumor
described in mechanism and pump of parietal cell HCl secretion
H+/K+ ATPase exchange and chloride channel
Secretion of chloride is accomplished through a chloride channel moving chloride from the parietal cell cytoplasm to the gastric lumen.
risk factors for afferent loop syndrome with Billroth II
limb greater than 30-40 cm - usually the problem
Antecolic anastomosis to stomach
internal herniation behind the efferent limb,
stenosis of the gastrojejunal anastomosis,
redundant twisting of the afferent limb with a resultant volvulus
adhesions involving the afferent limb.
two treatment options of afferent loop syndrome with Billroth II
enteroenterostomy below the stoma, which is technically easier.
Creation of a Roux-en-Y can also be done.
management of symptomatic duodenal periampullary diverticulum
uncomplicated duodenal diverticula:
diverticulectomy with primary closure
If perforation of diverticula:
diversion
gastrojejunostomy
or
duodenojejunostomy
cause pancreatitis or cholangitis do require surgical intervention
The accepted treatment for H.pylori includes
a triple medication regiment. This includes a PPI and two antibiotics.
The best choices for antibiotics are
Amoxicillin, Flagyl,
Tetracycline, and Clarithromycin.
PPI’s are superior to H2 blockers.
Laparoscopic adjustable gastric bands compare to bypass
can produce the same weight loss and improvement in comorbidities as roux-en-Y gastric bypass!
The caveat is that LAGB usually requires patients who are more motivated to lose weight.
Patients who undergo gastric bypass usually lose weight faster but weight loss steadily continues after LAGB.
The two procedures can show similar total excess weight loss at the 3- year mark.
5 –year-outcomes for patients receiving LAGB show about 60% of excess weight loss.
Improvement in hypertension in patients status post LAGB has been quoted as high as 55%. Similarly improvements are seen in GERD, diabetes, obstructive sleep apnea and quality of life.
Operative mortality after LAGB is estimated to be 0.1%. It is a safe procedure that is usually done on an outpatient basis.
for patients with acute NSAID-related perforation of duodenum what is recommended treatment
In general, simple patch closure, typically with omentum, is appropriate
(provided that use of the drugs can be discontinued post-operatively)
and for patients who have never been treated for peptic ulcer disease.
Simple patch repair should also be used for patients with ongoing shock, delayed evaluation, considerable co-morbid disease, or marked peritoneal contamination.
3-0 silk or PDS sutures
The most common and effective procedures for Gastroparesis
insertion of gastric pacers
pyloroplasty.
NOT endoscopy with botox injections or stent placement,
As a last resort, some patients may need to have a surgical feeding tube placed or started on TPN if their nutritional state is critical, but this should only be used once all other options have failed.
Cisapride use has been discontinued due to its side effect profile which includes prolonged QT syndrome and sudden cardiac arrest.
Gastroparesis most common cause
3 vagal injuries.
most common cause is idiopathic!!
other causes: #2 Diabetes is the second most common cause
The most common surgical procedure that leads to a vagal injury is a Nissen fundoplication.
Other causes:
narcotics
octreotide
scleroderma
electrolyte abnormalities.
The gold standard in diagnosis Gastroparesis
gastric emptying study which will show a slowed transit of radiolabelled ingested food over the course of several hours.
If gastroparesis is suspected, it is important to perform an upper endoscopy to ensure there is no true mechanical obstruction, such as a mass or ulcer, which is the cause for the symptoms.
A sham feeding test can help determine if there is poor vagal function after eating a meal.
accepted treatment for gastroparesis
Reglan
if fail med - pyloroplasty / pacemaker
Sleeve gastrectomy vascular moves to address greater curve
During the operation for sleeve gastrectomy, the greater curvature of the stomach is completely devascularized prior to being resected.
Sleeve gastrectomy Blood supply
Blood supply to the gastric sleeve is received from the left and right gastric arteries as well as branches from the right gastroepiploic.
comparing a parietal cell vagotomy to a truncal vagotomy for an acid suppressing surgery
Parietal cell vagotomy has less
post-operative diarrhea than a truncal vagotomy
recurrence rates depend on the experience of the surgeon
Drainage procedures are not required with a parietal cell vagotomy - preservation of the innervation to the gastric antrum.
Truncal vagotomy patients more frequently have post-operative dumping syndrome
Generally speaking, the caveat is an increased recurrence rate of ulcers due to the increased complexity of the surgery.
Most recurrent ulcers after a parietal cell vagotomy are treated with
MEDICAL therapy alone to achieve cessation of symptoms!
Bleeding duodenal ulcers are usually a result of
a posterior perforation into the gastroduodenal artery.
treatment of a posterior perforation into the gastroduodenal artery.
Stable patients:
endoscopy clip or inject the vessel for hemostasis.
If the patient rebleeds but remains stable:
a second attempt at endoscopic therapy can be used.
ANY hemodynamic instability or the need for over 4 units of blood:
operative intervention.
In a patient with a HISTORY / KNOWN ulcer disease:
truncal vagotomy with pyloroplasty after oversewing the vessel through an anterior duodenotomy
If dietary modifications fail, what is next step in tx of gastroparesis
promotility agents can be used.
Reglan is a dopamine antagonist that has shown to be effective in increasing gastric motility.
Erythromycin is also commonly used and acts upon the motilin receptors to aid in gastric function.
A final treatment option for gastroparesis
surgery, and this includes gastric pacer implantations,
pyloroplasty,
botox injections (most be injecting sympathetic here?)
partial gastrectomy.
These have varying degrees of effectiveness and should be used as a last resort.
Gastric carcinoid
rare,
10% of all GI carcinoids
and
2% of all gastric tumors.
The median age at diagnosis is 64,
Gastric carcinoid tumors have been divided into three types, primarily on the basis of their association (or lack thereof) with hypergastrinemia.
For patients with multiple or recurrent gastric carcinoid tumors what is the treatment
antrectomy to remove the source of the hypergastrinemia.
For patients with type II (MEN ASSO) lesions, treatment is similar to that for patients with type I lesions, with the extent of gastric resection determined by the size and number of lesions.
All patients undergoing a less than total gastrectomy should be followed with serial endoscopy at regular intervals.
Endoscopic polypectomy or open resection via gastrotomy (local excision) is the procedure of choice for patients with small, SOLITARY type I tumors.
Distal or total gastrectomy with extended lymph node dissection is the treatment of choice for patients with type III (SPORATIC AGGRESSIVE) lesions.
what is the pump responsible for secretion of HCl into the gastric lumen?
H+/K+ exchange and chloride channel
H+/K+ ATPase
final common pathway for gastric acid secretion by the parietal cell.
Cytosolic hydrogen is secreted by the H+/K+ ATPase in exchange for extracytoplasmic potassium.
The secretion or exchange of hydrogen for potassium, however, does require energy in the form of adenosine triphosphate (ATP), because hydrogen is being secreted against a gradient of more than a million-fold.
Secretion of chloride is accomplished through a chloride channel moving chloride from the parietal cell cytoplasm to the gastric lumen.
In patients who are stable and do not warrant an endoscopic evaluation, confirmation of H.pylori can best be achieved with what test
serologic studies.
This method has high sensitivity and specificity, is cost effective, and is the least invasive.
After treatment, the best test for eradication of the bacteria is with
urea breath test.
Testing should be delayed for four weeks to ensure reliable results.
Bottom Line: The best diagnostic test for H.pylori is serology and for eradication is the urea breath test.
If the patient needs to be evaluated with endoscopy for concern of brisk bleeding or perforation upon initial evaluation, then what is best test
Endoscopic bx with rapid urease assay is recommended for diagnosis.
Type 1 hiatal hernias
called a sliding hernia
most common
gastroesophageal (GE) junction lying above the diaphragm.
only type that can be treated non-operatively with proton pump inhibitors.
Type II hiatal hernias
paraesophageal hernia,
GE junction is fixed
true hernia sac where the fundus of the stomach herniates into the chest.
Regardless of the severity of symptoms paraesophageal hernias should be electively repaired once found because of the risk of incarceration
Type III hiatal hernias
second most common
GE junction lies above the diaphragm
stomach (and possibly other organs) herniate into the chest
Enlargement of the hernia allows the stomach and sometimes other organs to protrude through the hernia sac
most common nonepithelial cell tumors of the small bowel
GISTs
GIST most common locations
50% gastric
25% small bowel
15% rectal
10% colonic in origin
Rates of laparoscopic adjustable gastric band slippage have been reduced by utilization of what technique
the pars-flaccida technique.
This method utilizes dissection through the fatty tissue posterior to the gastroesophageal junction to create a tunnel in which the band sits.
The band is held in place by this connective tissue and reduces the chances that the posterior stomach, which is relatively mobile, will slip past the band.
Today band slipping should occur with what percent with LAGB
less than 3% of patients with LAGB placed using the pars-flaccida technique.
After band placement, the first band fill usually occurs
6 weeks later.
This allows time for local edema to subside.
