Peptic ulcer disease Flashcards
Define peptic ulcer disease
Ulceration of the UGI mucosa which may extend to and through the muscle layers
Name protective mechanisms in the mucosa
Bicarbonate
Blood flow
Prostaglandins
Mucus
Name injurious mechanisms of mucosa
H.pylori
Gastric acid
Pepsin
NSAIDs
Which substance is produced by the gastric parietal cells?
Hydrochloric acid
Intrinsic factor
Which substance is produced by the gastric chief cells?
Pepsinogen
Gastric lipase
Where are HCl and pepsinogen produced?
Gastric fundus and corpus
Discuss the formation of hydrochloric acid
- H20 and C02 catalysed by carbonic anhydrase in parietal cell cytoplasm to form H2CO3
- H+ derived from H2CO3 dissociation
- H+ transported against [ ] gradient into gastric lumen via H+/K+ pump
- Chloride follows H+ from blood into lumen to form HCl
What is the normal pH of gastric fluid?
2-3
Name the main actions of HCl
- Denaturation and unfolding of complex protein structures
- Activation of pepsinogen to pepsin to digest protein polypeptides
- Killing microbials ingested with food
Name the 3 phases of gastric stimulation
Cephalic
Gastric
Intestinal
Discuss the cephalic phase of gastric stimulation
Thought, smell, sight, taste, chewing, swallowing -> vagus nerve activation
- Acetylcholine and Ca2+ activate parietal cells -> H+
- Gastrin releasing peptide activates antral G-cells -> gastrin
Explain the role of gastrin
Stimulates parietal cells to secrete H+ via Ca2+
Activates enterochromaffin-like cells to secrete H+
Discuss the gastric phase of gastric stimulation
Distension of stomach by food
- Vago-vagal and local stretch receptors -> parietal Ach receptors
- Peptides and amino acids stimulated antral G-cells -> gastrin
Discuss the intestinal phase of gastric stimulation
10% HCl
Chyme enters the duodenum
1. Stretch receptors stimulate secretin by S-cells and D-cells -> somatostatin and cholecystokinin
2. Entero-oxyntin via hormonal stimulation
Discuss the intestinal phase of gastric stimulation
Chyme enters the duodenum
- Stretch receptors stimulate secretin by S-cells and D-cells -> somatostatin and cholecystokinin
- Entero-oxyntin via hormonal stimulation
Which phase of gastric stimulation produces the most HCl?
Gastric (60%)
Cephalic (30%)
Intestinal (10%)
Which mechanisms protect the GIT mucosa from acid-peptic damage?
- Bicarbonate (gastric mucus cells, pancreatic secretions, biliary secretions)
- Viscus mucus
- Prostaglandins
- Hormones inhibit secretion (somatostatin, secretin, cholecystokinin)
- Alkaline saliva
- Good blood flow
How does H.pylori increase acid production?
Bacteria produces urease
Urea -> ammonia
Mucosa -> alkaline
G-cells stimulated to produce gastrin
Name factors that increase acid production
H.pylori G-cell hyperplasia G-cell adenoma Diet Alcohol Smoking Steroids NSAIDs Physiological stress
Name common sites of peptic ulceration
1st part of duodenum
Pyloric antrum
Lesser gastric curvature
Name uncommon sites of peptic ulceration
Distal oesophagus
Distal duodenum
Stomach at gastro-jejunal anastomosis
Meckel’s diverticulum
What should you suspect if there is ulceration at unusual GIT sites?
Zollinger-Ellison syndrome
Discuss the presentation of gastric vs duodenal ulcers
Dyspepsia for both
Gastric
- postprandial epigastric pain
- weight loss
Duodenal
- epigastric pain on fasting
- wake up in middle of the night
- weight gain
Name complications of peptic ulcers
Perforation Bleeding Gastric outlet obstruction Oesophageal stricture Fistulas
What may lower oesophageal strictures be associated with?
Development of epiphrenic diverticulum due to weakness in mm wall and increased intraluminal pressure
Discuss the presentation of perforated peptic ulcer
Acute abdomen!
Sudden onset of severe pain Lucid interval Shock Increased HR, temp, RR Decreased BP Generalised abdominal tenderness Board-like rigidity
What is the reason for the lucid interval in PUD perforation?
Initial chemical peritonitis diluted by inflammatory exudate
Name sites of pus collections after perforated peptic ulcer
Free peritoneal Subphrenic Subhepatic Paracolic Interloop Pelvic Pleural (rare)
How is perforated peptic ulcer diagnosed?
Erect CXR Erect AXR Abdominal U/S CT abdomen Bloods (WCC, CRP, lipase, amylase, Hb, UKE, Cr, ABG, lactic acid, culture, CMP)
Does absence of free air on CXR exclude perforation?
No!
Give a differential for free intra-abdominal gas
Perforated
- peptic ulcer
- colonic diverticulum
- appendicitis
- distal ileum (typhoid)
- caecum
Discuss the management of perforated peptic ulcer
Resus - supplemental O2 - fluids - keep warm - urinary catheter - CVP - oesophageal temperature - inotropes - analgesics - dextrose Empirical broad spectrum antibiotics Surgical intervention
Name indications for non-surgical treatment of perforated peptic ulcer
Minimal abdominal signs
Severe shock with comorbidities
How do you perform non-surgical treatment of perforated peptic ulcer?
Multiple U/S percutaneous drains
Pus for MC&S
Discuss the surgical intervention in perforated peptic ulcer
Omentopexy with 6 biopsies of affected GIT
Rinse abdomen thoroughly with 6L warm water
Discuss the follow up of post surgical perforated peptic ulcer patients
Full PPI and H.pylori eradication
6w F/U with endoscopy
What is the first line therapy for eradicating H. pylori?
7-14d
- PPI
- clarithromycin
- amoxicillin/metronidazole
What is the second line therapy for eradicating H. pylori?
Bismuth quadruple
OR
PPI
Levofloxacin
Amoxicillin
Name scoring systems used for outcome prediction in perforated peptic ulcer
Boey
PULP
Mannheim peritonitis index
ASA
Which parameters are evaluated in the Boey score?
Presentation within 24h
Presence of pre-op shock
Comorbidities
Which parameters are evaluated in the PULP score?
Presentation within 24h Presence of pre-op shock ASA Presence of - AIDS - malignancy - liver failure - Cr>30mmol/l
Which parameters are evaluated in the Mannheim Peritonitis Index?
Age Gender Organ failure Peritonitis duration Site of perforation Diffuse peritonitis Level of exudate
Discuss the interpretation of the Boey score
1 point - 8% mortality, 47% morbidity
2 points - 33% mortality, 75% morbidity
3 points - 38% mortality, 77% morbidity
Name investigations in suspected peptic ulcer bleeding
FBC UKE Cr Lactic acid ABG INR PPT Platelets
Discuss grade 1 of hemorrhagic shock
<750ml/15% blood loss HR<100 Normal BP RR 14-20 Urine output >30ml/hr
Discuss grade 2 of hemorrhagic shock
750-1500ml/15-30% blood loss HR 100-120 Normal BP RR 20-30 Urine output 20-30ml/hr
Discuss grade 3 of hemorrhagic shock
1500-2000ml/30-40% blood loss HR 120-140 Decreased BP RR 30-40 Urine output 5-20ml/hr
Discuss grade 4 of hemorrhagic shock
>2000ml/40% blood loss HR >140 Decreased BP RR >35 Negligible urine output
From what grade of hemorrhagic shock is blood used as fluid replacement?
Grade 3
Which fluids do we use in hemorrhagic shock?
Crystalloids
Discuss the management of hemorrhagic shock due to peptic ulcer
Resus
NGT
Lavage the stomach
Gastroendoscopy within 24h
Which classification is used for bleeding peptic ulcer?
Forrest
Discuss the Forrest Classification of bleeding peptic ulcer
I (active hemorrhage)
- Ia spurting
- Ib oozing
II (recent hemorrhage)
- IIa non-bleeding vessel
- IIb adherent clot
- IIc coffee ground
III (no hemorrhage)
- clean ulcer base
What is the risk of rebleed in a Forrest 1a on medical management?
90%
What is the risk of rebleed in a Forrest 1b on medical management?
10-20%
What is the risk of rebleed in a Forrest 2a on medical management?
50%
What is the risk of rebleed in a Forrest 2b on medical management?
25-30%
What is the risk of rebleed in a Forrest 2c on medical management?
7-10%
What is the risk of rebleed in a Forrest 3 on medical management?
3-5%
Which Forrest class is most prevalent?
Forrest 3
Discuss haemostatic procedures for bleeding peptic ulcer
Endoscopic
- saline/adrenaline
- thermal coagulation
- argon laser coagulation
- clip application
Surgical
- underrun
- figure of 8
Angiographic embolization
Name metabolic changes in protracted vomiting
Hypovolemia Renal insufficiency Alkalosis Hyponatremia Hypokalemia Hypochloremia Starvation
Why should you not infuse KCl via a CVP line?
Causes asystole and cardiac arrest
Discuss the definitive treatment of GOO due to peptic ulcer
TPN for 10-12d -> trial of clear fluid po -> mixed fluids -> fluid diet
IV PPI for 10-12d
Dilation/stoma
Post-op triple therapy
Discuss the presentation of gastro-colic fistula
Faecal eructations (belch) Postprandial diarrhea with undigested food
How is gastro-colic fistula diagnosed?
Barium enema
Gastroscopy w/ biopsy
Discuss the definitive management of gastro-colic fistula due to peptic ulcer
Endoscopic fibrin gel plug
Surgical resection
Post-op triple therapy
