Flashcards in Chapter 30: Stomach Deck (178):
Stomach transit time
Where does stomach peristalsis occur?
Distal stomach (antrum)
How is gastroduodenal pain sensed
Through afferent sympathetic fibers T5-T10
Components of the celiac trunk
Common hepatic artery
Branches of the splenic artery that supply the stomach
Left gastroepiploic and short gastric
Blood supply to the greater curvature
Right and left gastroepiploics, short gastrics
What is the right gastroepiploic a branch of?
Blood supply of lesser curvature
Right and left gastrics
What is the right gastric a branch off?
The common hepatic artery
Blood supply of the pylorus
Mucosa lining the stomach
Simple columnar epithelium
What do cardia glands secrete?
Fundus and body glands
Produces pepsinogen (1st enzyme in proteolysis)
Release hydrogen and intrinsic factor
What stimulates parietal cells?
Acetylcholine (vagus nerve), gastrin (from G cells in antrum), and histamine (from mast cells) cause H+ release
What is the pathway of acetylcholine (vagus nerve) and gastrin?
Activates phospholipase (PIP -> DAG + IP3 + Increase Ca); Ca-calmodulin activates phosphorylase kinase -> H+ release
What is the pathway of histamine?
Activates adenylate cyclase -> cAMP -> activates protein kinase A -> increased H+ release
How do phosphorylase and protein kinase A work?
Phosphorylate H+/K+ ATPase to increase H+ secretion and K+ absorption
Blocks H+/K+ ATPase in parietal cell membrane (final pathway for H+ release)
Inhibitors of parietal cells
Somatostatin, prostaglandins (PGE1), secretin, CCK
Binds B12 and the complex is reabsorbed in the terminal ileum
Antrum and pylorus glands
Mucus and HCO3- secreting glands.
G cells (gastrin).
D cells (somatostatin)
Secreting glands - protect stomach
Mucus and HCO3- (Antrum and pylorus glands)
Release gastrin - reason why antrectomy is helpful for ulcer disease
What inhibits G cells?
H+ in duodenum
What stimulates G cells?
Amino acids, acetylcholine
Secrete somatostatin, inhibit gastrin and acid release
In duodenum; secrete alkaline mucus
Released with antral and duodenal acidification
Somatostain, CCK, and secretin
What are the causes of rapid gastric emptying?
Previous surgery (#1), ulcers
What are the causes of delayed gastric emptying?
Diabetes, opiates, anticholingerics, hypothyroidism
(Hair) - hard to pull out
- Tx: EGD generally inadequate; likely need gastrostomy and removal
(fiber) - often in diabetics with poor gastric emptying
Tx: enzymes, EGD, diet changes
Vascular malformation; can bleed
Mucous cell hyperplasia, increased rugal folds
- Associated with type II (paraesophageal) hernia
- Nausea without vomiting; severe pain; usually organoaxial volvulus
Tx: reduction and Nissen
- Secondary to forceful vomiting
- Presents as hematemesis following severe retching
- Bleeding often stops spontaneously
What type of volvulus is a gastric volvulus?
Dx/Tx: Mallory Weiss Tear
EGD with hemo-clips; tear is usually on the lesser curvature (near GE junction)
Where is the Mallory Weiss Tear located?
Usually on the lesser curvature (near GE junction)
What if you have continued bleeding after EGD with hemo-clips for Mallory Weiss tear?
If continued bleeding, may need gastrostomy and oversewing of the vessel.
What is the physiologic effect of vagotomy?
Both truncal and proximal forms increase liquid emptying -> vaguely mediated receptive relaxation if removed (results in increased gastric pressure that accelerates liquid emptying)
Divides vagal trunks at the level of the esophagus; decreases emptying of solids
- highly selective
- divides individual fibers, preserves "crow's foot", normal emptying of solids
Emptying of solids: truncal vs proximal vagotomy
Truncal: decreased emptying of solids
Proximal: normal emptying of solids
How can you increase solid emptying with truncal vagotomy?
Addition of pyloroplasty to truncal vagotomy results in increased solid emptying.
Physiologic effects of truncal vagotomy
- Gastric effects
- Nongastric effects
- Gastric: decreased acid output by 90%, increased gastrin cell hyperplasia
- Nongastric: decreased exocrine pancreas function, decreased postprandial bile flow, increased gallbladder volumes, decreased release of vaguely mediated hormones
- Diarrhea: MC problem following vagotomy
MC common problem following vagotomy
What causes diarrhea following vagotomy?
Caused by sustained MMCs (migrating motor complex) forcing bile acids into the colon
Name that vagotomy: both nerve trunks are divided at the level of the diaphragmatic hiatus
Name that vagotomy: division of the vagal fibers that supply the gastric funds. Branches to the antropyloric region of the stomach are not transected, and the hepatic and celiac divisions of the vagus nerves remain intact.
Proximal gastric vagotomy
Risk factors: upper gastroinestinal bleeding
Previous UGIB, PUD, NSAIDs, smoking, liver disease, esophageal varices, splenic vein thrombosis, sepsis, burn injuries, trauma, severe vomiting.
EGD (confirm bleeding is from ulcer); can potentially treat with hemo-clips, Epi injection, cautery
Mgmt: UGIB with slow bleeding and having trouble localizing source
Tagged RBC scan
UGIB: biggest risk factor for rebleeding at the time of EGD
#1 spurting blood vessel (60%) chance of rebleed
#2 visible blood vessel (40% chance of rebleed)
#3 diffuse oozing (30% chance of rebleed)
Highest risk factor for mortality with non-variceal UGIB
Continued or re-bleeding
Treatment: patient with liver failure is likely bleeding from esophageal varices, not an ulcer
EGD with variceal bands or sclerotherapy; TIPS if that fails
- From increased acid production and decreased defense
- Most common peptic ulcer; more common in men
Location of duodenal ulcers
Usually in 1st part of the duodenum; usually anterior.
Complications of duodenal ulcers:
- Anterior ulcers perforate
- Posterior ulcers bleed from gastroduodenal artery
Symptoms: epigastric pain radiating to the back; abates with eating but recurs 30 minutes after
- Dx: endoscopy
- Tx: PPI, triple therapy for H. pylori -> bismuth salts, amoxicillin, and metronidazole/tetracycline (BAM or BAT)
What has decreased incidence of surgery for ulcer?
Surgery for ulcer rarely indicated since PPIs
What do you need to rule out in patients with complicated ulcer disease?
Need to rule out gastrinoma
Gastric acid hyper secretion.
Surgical indications for duodenal ulcer
Perforation. Protracted bleeding despite EGD therapy. Obstruction. Intractability despite medical therapy. Inability to rule out cancer. PPI with duodenal ulcer complication.
Duodenal ulcer: if patient has been on a PPI and has complications
If a patient has been on a PPI, an acid-reducing surgical procedure is required in addition to surgery for any complications
Surgical options (acid-reducing surgery) for duodenal ulcers
- Proximal vagotomy
- Truncal vagotomy and pyloroplasty
- Truncal vagotomy and antrectomy
- Reconstruction after antrectomy - Roux-en-Y gastro-jejunostomy (best)
Surgery duodenal ulcer: lowest rate of complications, no need for astral or pylorus procedure; 10-15% ulcer recurrence, 0.1% mortality
Ulcer recurrence / mortality after proximal vagotomy
- 10-15% ulcer recurrence
- 0.1% mortality
Ulcer recurrence / mortality after truncal vagotomy and pyloroplasty
- 5-10% ulcer recurrence
- 1% mortality
Ulcer recurrence / mortality after truncal vagotomy and antrectomy
- 1-2% ulcer recurrence (lowest rate of recurrence)
- 2% mortality
Why is roux-en-y gastro-jejunostomy the best procedure for reconstruction after antrectomy?
Less dumping syndrome and reflux gastritis compared to Bilroth I (gastro-duodenal anastomosis) and Billroth II (gastro-jejunal anastomosis)
Most frequent complication of duodenal ulcers
Bleeding (usually minor but can be life threatening)
Definition of major bleeding in duodenal ulcer
> 6 units of blood in 24 hours or patient remains hypotensive despite transfusion
Tx: bleeding from duodenal ulcer
EGD 1st - hemoclips , cauterize, Epi injection
Surgery: bleeding duodenal ulcers
Duodenotomy and gastroduodenal artery (GDA) ligation.
- Avoid hitting common bile duct (posterior) with GDA ligation
- If patient has been on a PPI, need acid-reducing surgery as well
Initial treatment of choice for obstruction from duodenal ulcer
PPI and serial dilation
Surgical options: duodenal ulcer obstruction
Antrectomy and truncal vagotomy (best); include ulcer in resection if it's located proximal to ampulla of Vater
What do you need to rule out in duodenal ulcer obstruction?
Need to biopsy area of resection to rule out CA
Duodenal ulcer perforation: % will have free air
80% will have free air
- patient usually have sudden epigastric pain; can have generalized peritonitis
- pain can radiate to the prevocalic gutters with dependent drainage of gastric content
Duodenal ulcer perforation
Tx: duodenal ulcer perforation
Graham patch (place momentum over the perforation)
- Also need acid-reducing surgery if the patient has been on a PPI
Definition of intractable duodenal ulcers
> 3 months without relief while on escalating doses of PPI
What is diagnosis of intractable duodenal ulcers based on?
Based in EGD mucosal findings, not symptoms
Tx: intractability of duodenal ulcers
- Older men, slow healing
- 80% on lesser curvature of the stomach
- Symptoms: epigastric pain radiating to the back; relieved with eating but recurs 30 minutes later; melena or guaiac-positive stools
Risk factors for gastric ulcer
Male, tobacco, ETOH, NSAIDs, H. pylori, uremia, stress (burns, sepsis, and trauma), steroids, chemotherapy
Where are most gastric ulcers located?
80% on lesser curvature of the stomach
What is difference in mortality between gastric and duodenal ulcer hemorrhage?
Hemorrhage is associated with higher mortality than duodenal ulcers.
Gastric ulcers: best test for H. pylori
Histiologic examination of biopsies from antrum
Test for H.pylori, detects urease released from H. pylori
CLO test (rapid urease test)
Type 1 Gastric ulcer
Lesser curve low along body of stomach; due to decreased mucosal protection
Type 2 gastric ulcer
2 ulcers (lesser curve and duodenal); similar to duodenal ulcer with high acid secretion
Type 3 gastric ulcer
pre-pyloric ulcer; similar to duodenal ulcer with high acid secretion
Type 4 gastric ulcer
Lesser curve high along cardia of stomach; decreased mucosal protection
Type 5 gastric ulcer
Ulcer associated with NSAIDS
What gastric ulcers are associated with decreased mucosal secretion?
Type 1 and 4
What gastric ulcers are similar to duodenal ulcer with high acid secretion?
Type 2 and 3
What type of gastric ulcer is associated with NSAIDS?
Surgical indications for gastric ulcers
Perforation, bleeding not controlled with EGD, obstruction, cannot exclude malignancy, intractability (> 3 months without relief - based on mucosal findings)
Tx: gastric ulcer
Truncal vagotomy and antrectomy best for complications; try to include the ulcer with resection (extended antrectomy) - need separate ulcer excision if that is not possible (gastric ulcers are resected at time of surgery due to high risk of gastric CA)
What are poor options for surgical repair of gastric ulcers?
Omental patch and ligation of bleeding vessels are poor options for gastric ulcers due to high recurrence of symptoms and risk of gastric CA in the ulcer.
- Occurs 3-10 days after event; lesions appear in fundus first
- Tx: PPI
- EGD with cautery of specific bleeding point may be effective
Where do lesions in stress gastritis appear?
Lesions appear in fundus first
Chronic gastritis type: associated with pernicious anemia, autoimmune disease
Type A (fundus)
Chronic gastritis type: associated with H. pylori
Type B (antral)
Treatment Chronic Gastritis
Pain unrelieved by eating, weight loss
Where are 40% of gastric cancers located?
Gastric cancer-related deaths in Japan
Accounts for 50% of cancer-related deaths in Japan
Dx: gastric cancer
Risk factors: gastric cancer
Adenomatous polyps, tobacco, previous gastric operations, intestinal metaplasia, atrophic gastritis, pernicious anemia, type A blood, nitrosamines
15% risk of gastric cancer.
- Tx: endoscopic resection
Gastric cancer metastases to ovaries
Gastric metastasis to supraclavicular node
Increased in high-risk populations. Older men. Japan. Rare in United States
Surgical treatment: try to perform subtotal gastrectomy (need 10-cm margins)
Intestinal-type gastric CA
Low risk populations. Women. Most common type in the United States.
Diffuse lymphatic invasion, no glands.
Surgery: total gastrectomy bc of diffuse nature of linitis plastica
Diffuse gastric cancer
Prognosis: intestinal-type gastric CA vs diffuse gastric cancer
Less favorable prognosis than intestinal-type gastric CA (overall 5-YS - 25%)
Margins for intestinal-type gastric CA
need 10 cm margins
Chemotherapy for gastric cancer
- 5 FU, doxorubicin, mitomycin C
Gastric cancer: management of metastatic disease outside area of resection
Contraindication to resection unless performing surgery for palliation.
When to consider palliation of gastric cancer?
- Obstruction - proximal lesions can be scented; distal lesions can be bypassed with gastrojejunostomy
- Low to moderate bleeding or pain - Tx: XRT
What if surgical management fails for palliation of gastric cancer (stents, gastrojejunostomy, XRT)?
If these fail, consider palliative gastrectomy for obstruction or bleeding.
Most common benign gastric neoplasm, although can be malignant
Symptoms: usually asymptomatic, but obstruction and bleeding can occur
Gastrointestinal stromal tumors (GISTs)
How do GISTs look on ultrasound?
Hypoechoic on ultrasound; smooth edges
Dx / Tx: GIST
Dx: biopsy - are C-KIT positive
Tx: resection with 1 cm margins; Chemotherapy with imatinib (Gleevac, tyrosine kinase inhibitor) if malignant
Chemotherapy for malignant GIST
Imatinib (Gleevax; tyrosine kinase inhibitor)
- Related to H. pylori infection
- Usually regresses after treatment for H. pylori
Mucosa-associated lymphoid tissue lymphoma (MALT lymphoma)
When are GIST considered malignant?
> 5 cm or > 5 mitoses / 50 HPF (high-powered field)
What will be positive in biopsy of GIST?
MC location of MALT lymphoma
Treatment: MALT lymphoma
Triple-therapy antibiotics for H. pylori and surveillance.
If MALT does not regress, need XRT.
What if MALT lymphoma does not resolve with triple therapy antibiotics for H.pylori?
If MALT does not regress, need XRT
- Have ulcer symptoms
- Usually non-Hodgkin's lymphoma (B cell)
- Overall 5-year survival rate > 50%
MC location for extra-nodal gastric lympoma
Dx: Gastric lymphoma
EGD with biopsy
Primary treatment modalities of gastric lymphoma
Chemotherapy and XRT are primary treatment modalities; surgery for complications
When is surgery indicated for gastric lymphoma?
Surgery possibly indicated only for stage 1 disease (tumor confined to stomach mucosa) and then only partial resection is indicated
Overall 5-year survival rate for gastric lymphoma
Criteria for patient selection for bariatric surgery (need all 4)
- BMI > 40 kg/m^2 or BMI > 35 kg/m^2 with coexisting comorbidities
- Failure of nonsurgical methods of weight reduction
- Psychological stability
- Absence of drug or alcohol abuse
What type of obesity is worse prognosis in general population?
Operative mortality in morbid obesity
What gets better are surgery for morbid obesity?
DM, cholesterol, sleep apnea, HTN, urinary incontinence, GERD, venous stasis ulcers, pseudotumor cerebri, joint pain, migraines, depressions, PCOS, NASH
- Better weight loss than just banding.
- Risk of marginal ulcers, leak, necrosis, B12 deficiency, IDA, gallstones
- Perform cholecystectomy during operation if stones present
- UGI on POD 2
Roux-en-Y gastric bypass
Failure rate of roux-en-y gastric bypass
10% failure rate due to high-carbohydrate snacking
What are the signs of a leak after roux-en-y gastric bypass?
- Ischemia: MCC leak
- Signs of leak: increased RR, increased HR, abdominal pain, fever, elevated WBCs
Dx / Tx: leak after roux-en-y gastric bypass
Tx: early leak (not contained) -> re-op; late leak (Weeks out from surgery, likely contained) -> percutaneous drain, antibiotics
Incidence of marginal ulcers after roux-en-y gastric bypass
Develop in 10%
Management of stenosis after roux-en-y gastric bypass
Usually responds to serial dilation
Complications of roux-en-y gastric bypass
- Marginal ulcers
MCC leak after roux-en-y gastric bypass
After roux-en-y gastric bypass:
- Hiccoughs, large stomach bubble
- Dx: AXR
- Tx: G-tube (gastrostomy tube)
Dilation of excluded stomach postop
s/p roux-en-y gastric bypass:
- nausea and vomiting, intermittent abodminal pain
- AXR shows dilated SB
Small bowel obstruction
- Surgical emergency
Why is SBO s/p roux-en-y gastric bypass a surgical emergency?
Due to the high risk of small bowel herniation, strangulation, infarction and subsequent necrosis.
- Tx: surgical exploration
- these operations are no longer done
- a/w liver cirrhosis, kidney stones, and osteoporosis (decreased calcium)
- need to correct these patients and perform roux-en-y gastric bypass if encountered
- can occur after gastrectomy or after vagotomy and pyloroplasty
- occurs form rapid entering of carbohydrates into the small bowel.
- can almost always be treated medically (and dietary changes)
2 phases of dumping syndrome
- Hyperosmotic load causes fluid shift into bowel (hypotension, diarrhea, dizziness)
- hypoglycemia from reactive increase in insulin and decrease in glucose (2nd phase rarely occurs)
Tx: dumping syndrome
Small, low-fat, low-carb, high-protein meals; no liquids with meals, no lying down after meals; octreotide
Surgical options for dumping syndrome (Rarely needed)
- Conversion of Billroth 1 or Billroth 2 to Roux-en-y gastrojejunostomy
- Operations to increase gastric reservoir (jejunal pouch) or increased emptying time (Reversed jejunal loop)
postprandial epigastric pain associated with n/v; pain not relieved with vomiting
Alkaline reflux gastritis
Dx / Tx: alkaline reflux gastritis
Dx: evidence of bile reflux into the stomach; histologic evidence of gastritis
Tx: PPI, cholestyramine, metoclopramide
Surgical options for alkaline reflux gastritis
Conversion of Billroth 1 or Billroth 2 to Roux-en-Y gastrojejunostomy with afferent limb 60 cm distal to gastro jejunostomy
- Delayed gastric emptying
- Symptoms: n/v, pain, early satiety
Chronic gastric atony
Chronic gastric atony:
Dx / Tx / Surgical options
Dx: gastric emptying study
Tx: metoclopramide, prokinetics
Surgical option: near total gastrectomy with roux-en y
- Early satiety
- Actually want this for gastric bypass patients
Small gastric remnant
Small gastric remnant:
Dx / Tx / Surgical option
- Dx: EGD
- Tx: small meals
- Surgical option: jejunal pouch reconstruction
- With billroth 2 or roux-en-y; caused by poor motility
- Symptoms: pain, steatorrhea (bacterial beconjugation of bile), B12 deficiency (bacteria use it up), malabsorption
What causes blind-loop syndrome with billroth 2 or roux-en-y?
Caused by bacterial overgrowth (E coli, GNRs) from stasis in afferent limb
Dx: blind-loop syndrome
EGD of afferent limb with aspirate and culture for organisms
Tx: blind loop syndrome
Tetracycline and flagyl, metoclopramide to improve motility
Surgical option: blind-loop syndrome
Re-anastomosis with shorter (40-cm) afferent limb to relieve obstruction
- Symptoms of obstruction - n/v, abdominal pain
- Dx: UGI, EGD
- Tx: balloon dilation
- Surgical option: find site of obstruction and relieve it
- Secondary to non-conjugated bile salts in the colon (osmotic diarrhea)
- Causes by sustained postprandial organized MMCs
Tx / Surgical option: post-vagotomy diarrhea
Tx: cholestyramine, octreotide
Surgical option: reversed interposition jejunal graft
What causes post-vagotomy diarrhea?
Reversed interposition jejunal graft
Management: duodenal stump blow-out
Place lateral duodenostomy tube and drains