Stomach Flashcards
Cells in the fundus & secretions
Chief: pepsinogen
Parietal: HCL, intrinsic factor
Enterochromaffin-like cells: Histamine
Cells in pylorus & secretions
D cells: somatostatin
G cells: gastrin
Cells in duodenum & secretions
I cells: CCK (increase gallbladder & pancreas actions)
K cells: gastric inhibitory peptide (stimulate insulin production)
M cells: motilin (increase intestinal motility). erythromycin - motilin agonist
S cells: secretin (increase pancreas bicarb, decrease gastrin & HCL)
Blood supply to stomach
1) Celiac trunk
1a) Left gastric artery
1b) Splenic artery
1c) Common hepatic
2) Left gastric
2a) Eosophageal branches
3) Splenic
3a) Short gastric (supply fundus)
3b) Left gastroepiploic
4) Common hepatic
4a) Hepatic -> right gastric
4b) Gastroduodenal -> Right
gastroepiploic
The ligament of ___ is a suspensory ___ of the ___ that connects the ___ to ___
Treitz
suspensory muscle connecting DJ flexure to connective tissue surrounding celiac axis & SMA
*bleeding proximal to this ligament = UBGIT
Haemoptysis vs Haematemesis
Haemoptysis
- bloody expectorant from respi system
- pt experience sensation in their throat, blood is frothy & bright red
Haematemesis
- Vomited blood
- Fresh red blood = moderate to severe bleeds
- Coffee-ground vomitus = altered blood due to gastric acid, limited bleeding
- Usually melena can be observed
Types of melena
Fresh: jet black, tarry stool, non-particulate, almost liquid
Stale: black-grey, dull, can be particulate (could be bleed that has stopped)
Ddx of black stools
Iron stools - from consumption of iron supplement
- Greenish on rubbing between fingers, particulate
Haematemesis can be due to ___ or ___ bleeds
variceal
non-variceal
Causes for variceal bleed
Chronic liver disease -> portal hypertension -> portosystemic shunting -> dilated oesophageal veins
Causes of non-variceal bleed
Peptic ulcer disease
Stress ulcer
Mallory-Weiss tear
Dieulafoy (AVM of gastric fundus)
Malignancy (gastric/oesophageal CA)
Gastric antral vascular ectasia
What can cause peptic ulcer disease?
H.pylori
Drugs: NSAIDs, antiplts, steroids (delay healing), TCM
Smoking
Others: Zollinger Ellison syndrome, hypergastrinemia, stress, head trauma, burns, alcohol
What causes mallory-weiss tear?
Violent retching following alcoholic binge
Longitudinal fissures occur in the mucosa of herniated stomach at GEJ
Suspect ___ in pts with BGIT without history of NSAIDs or alcohol abuse
Dieulafoy (AV malformation)
questions to ask to classify when assessing UBGIT
1) haematemesis vs haemoptysis
2) variceal vs non-variceal
3) quantify amt of bleeding
4) comorbidities
Classifying non-variceal UBGITs
1) oesophagus - MW tear, esophagitis, cancer, boerhaave
2) stomach - PUD, gastritis, cancer, dieulafoy
3) duodenum - PUD, lymphoma, periampullary cancers, trauma
4) others
For fluid resus, two large bore __ ___ should be inserted at antecubital fossa
18G IV cannula
Bloods to order in haemodynamically unstable pts
GXM
FBC
Urea/Cr/E - renal function (isolated uremia = UBGIT)
LFT
PT/PTT/INR
Troponin - risk of MI with severe blood loss
ABG/Lactate
__ tube should be inserted when pt having haematemesis UNLESS suspect ___
NG - prevent aspiration, allow gastric lavage prior to OGD
unless suspecting variceal bleed - NG tube will worsen bleed
Targets for fluid resus is to maintain ___, ___, ___
Hb >7 / >9 (IHD)
MAP: >60mmHg (perfuse end organs)
Urine output: >0.5ml/kg/hr
What is massive blood transfusion?
Transfusion of pt entire blood volume within 24 hrs
Complications of massive blood transfusion
Lethal triad: Acidosis, hypothermia, coaulopathy
Acute haemolytic transfusion reaction
Acute febrile non-haemolytic transfusion risk: from pt Abs attacking donor WBC/HLA antigens
Two veins in portosystemic anastomosis that leads to variceal bleeds
systemic: Oesophageal branch of azygos
portal: Left gastric veins
Risk factors for variceal bleeding
Risk for development of varices: Hepatic venous pressure gradient >10mmHg
Risk of bleed: varices size, decompensated cirrhosis, endoscopic stigmata of recent haemorrhage
Emergency management of severe variceal bleed is by ____ with a ___ tube that consists of ___
balloon tamponade
Sengstaken-Blakemore tube
gastric & oesophageal balloons + gastric/eosophageal aspiration openings
Predictors of variceal haemorrhage
1) Site: GEJ
2) Size: Grade 1-3
3) Child’s score
4) Endoscopic stigmata of recent haemorrhage: red wale marks, cherry red spots, haematocystic spots, erythema
5) Previous haemorrhages
Locations of peptic ulcers
Duodenum (75%)
Stomach - antrum (20%), lesser/greater curve
Oesophagus
Multiple sites = suspect ZES
Gastric ulcer pain pattern vs duodenal ulcer pain pattern
Gastric: pain occurs after eating, pts tend to avoid food and lose weight
Duodenal: pain when hungry, relieved by food
Protective mechanisms against ulcer formation
Bicarbonate, mucus secretion
Mucosal blood flow to remove protons
Epithelial regenerative capacity
Prostaglandins to maintain blood flow
What are prostaglandins in the stomach impt for? How are they affected by NSAIDs?
NSAIDs impair prostaglandin synthesis
PG: increase bicarb & mucus secretion, promote blood flow, inhibit gastric acid secretion
H. pylori effect on stomach
Inhibits antral D cells, decrease somatostatin -> increased gastrin -> increased HCL -> gastric metaplasia in duodenum
Decreased bicarb in duodenum + increased inflammation = duodenal ulcer
Symptoms of dyspepsia
Ulcer-like dyspepsia: burning, gnawing, intermittent epigastric pain
Dysmotility-like dyspepsia: non-painful, bloating, belching, early satiety, N/V
Unspecified dyspepsia
Clinical manifestation of perforated ulcer
Abdominal rigidity, involuntary guarding, generalised pain that worsens on movement
Fever, hypotension, tachycardia, sepsis
Impt to order ___ when suspecting perforated ulcer
Erect chest X ray - detect free air under diaphragm
Diagnostic method for H.pylori
Endoscopic biopsy for CLO (campylobacter-like organism) test: biopsy tissue placed in medium containing urea & phenol red. If H.pylori present to cleave urea, becomes ammonia and pH increase, phenol red change from yellow to red
4 main complications for peptic ulcer disease
1) bleed
2) burst
3) block
4) burrow - ulcer penetrates into adjacent abdominal organs, leads to other diseases (eg. pancreatitis)
Risk factors for gastric cancer
H.pylori/EBV infection
Environmental - smoking, diet (preserved food)
Genetic - family history, FAP/HNPCC, familial diffuse gastric cancer
PMH - Barrett’s, gastric polyps/ulcers, gastric resection, chronic atrophic gastritis
Classification of gastric tumours
Boormann’s
Type 1: polypoid (tumour mostly intraluminal)
Type 2: excavating (ulcerated)
Type 3: ulcerative (tumour mostly in the wall)
Type 4: diffuse thickening/linitis plastica (entire thickness of stomach involved)
Most common location of stomach for gastric cancer occurrence
Lesser curvature of the antropyloric region
Most gastric cancers are ___. Subtypes are ___
adenocarcinomas
a) intestinal type
- usually elderly men
- papillary, tubular, mucinous
- atrophic gastritis -> severe intestinal metaplasia -> dysplasia
- less aggro
- haematogenous spread
b) diffuse type
- younger, females
- invasive, linitis plastica pattern (signet ring cells)
- late presentation, worse prognosis
- transmural, lymphatic spread
Examples of non-adenocarcinomas of the stomach
gastric neuroendocrine tumours (carcinoids) -> from enterchromaffin like cells
lymphoma (MALT)
gastrointestinal stromal tumour (GIST)
leiomyoma/leiomyosarcoma
Cx of gastric cancer
Bleeding
Gastric outlet obstruction
Intestinal obstruction (carcinomatosis peritonei)
Malnutrition
Perforation
GOO presents as ____ in blood investigations
hypochloremic, hypokalaemic, metabolic alkalosis with paradoxical aciduria
Lymphatic spread of GIT cancers result in enlarged __ node at ___
Virchow’s
Left supraclavicular region
Modes of spread of gastric cancer
1) Local - pancreas, transverse colon, duodenum
2) Lymphatic - Virchow’s node, perigastric lymph node, para-aortic nodes
3) Haematogenous - lung, hepatosplenomegaly
4) Trans-coelomic - peritoneal seeding, Sister Mary Joseph nodule, Krukenburg tumour (ovary)
___ is used to determine ___ of tumour invasion in gastric cancer, which is an important prognostic factor
Endoscopic ultrasound
depth of tumour invasion
*superior to CT in detecting depth
Types of gastrectomies
Total - everything gone including cardia & pylorus
Distal - cardia preserved
Pylorus preserving - upper 1/3, pylorus, antrum preserved
Proximal - pylorus preserved
Gastric reconstruction options
1) Billroth I (gastroduodenostomy)
2) Billroth II (gastrojejunostomy)
3) Roux-en-Y esophagojejunostomy
4) Double tract
Signs of anastomotic leak post gastrectomy
TACHYCARDIA (early sign)
early leak - sepsis, contaminated drain discharge
Late cx of gastrectomy
1) early satiety
2) Gastroesophageal reflux -> esophagitis
3) Dumping syndrome
What is dumping syndrome?
Post gastrectomy, rapid gastric emptying
Hyperosmolar jejunal chyme -> draws water into lumen -> decreased blood volume (hypotension, tachycardia) + abdominal bloating (diarrhea)
Rapid glucose absorption -> reactive hyperinsulinemia -> hypoglycaemia
Nutritional supplement requirements post gastrectomy
B12 (no more IF to bind)
Iron (no more conversion from Fe3 to Fe2 by gastric acid)
Vitamin D (fat malabsorption)
Loop syndrome occurs when?
Billroth II (gastrojejunostomy)
Kinking, narrowing, adhesions of the jejunum causing mechanical obstruction
Extranodal lymphoma most commonly occurs in ___
stomach
- marginal zone B cell lymphoma of mucosal associated lymphoid tissue (MALT)
- diffuse large B cell lymphoma
Gastrointestinal stromal tumours are a type of ___. They are positive for ___ marker, and arises from ___.
soft tissue sarcoma of GI tract
CD117
interstitial cell of Cajal
Risk factors for obesity
Genetics
Environment: diet, culture
What are common complications of obesity?
T2DM, HTN, HLD, cardiovascular disease
GERD, cholelithiasis, asthma, depression, degenerative joint disease
