Gastro Notes Summary

Upper GI Bleed

  • Peptic ulcers (H. pylori/NSAIDs)
  • Oesophageal varices
  • Mallory-Weiss tears
  • Use Blatchford score

Lower GI Bleed

  • Diverticular disease
  • Angiodysplasia
  • Ischemic colitis
  • Hemorrhoids

Vomiting

  • GI, CNS, endocrine causes
  • Anti-emetics by class
  • Prochlorperazine, metoclopramide
  • Ondansetron for chemo

Diarrhea

  • Acute vs chronic
  • Infectious causes
  • C. difficile management
  • Bloody vs non-bloody

Liver Disease

  • Hepatocellular vs cholestatic
  • Acute liver failure
  • LFT patterns
  • N-acetylcysteine for OD

Biliary/Pancreatic

  • Acute pancreatitis
  • GET SMASHED mnemonic
  • Cholangitis triad
  • Ranson's criteria

GASTRO NOTES

Comprehensive guide to gastrointestinal disorders

Upper GI Bleed

Causes

  • Peptic ulcer disease (H. pylori/NSAIDs)
  • Oesophagitis/Gastritis/Duodenitis
  • Oesophageal varices (portal hypertension)
  • Mallory-Weiss tear
  • Malignancy (gastric carcinoma)
  • Coagulation disorders
  • Aortoenteric fistulas (post-aortic surgery)
Blatchford Score for Admission Risk
Parameter Score
Blood urea 6.5-82
Blood urea 8-103
Blood urea 10-254
Blood urea >256
Hb (men) 100-1193
SBP 100-1091
Other markers (each)1-2

Variceal Bleed Management

  1. IV fluids/PRBC if compromised
  2. Terlipressin + Antibiotics (Cipro/3rd Gen Cephalosporin)
  3. Endoscopic banding
  4. Balloon tamponade (Sengstaken-Blakemore) if endoscopy fails
  5. TIPS or esophageal stent

Ulcer Bleed Management

  1. IV fluids/PRBC if compromised
  2. Endoscopy: Adrenaline + thermal coagulation
  3. PPI if stigmata of recent hemorrhage
  4. Radiological embolization/surgery if failed

Lower GI Bleed

Causes

  • Diverticular disease (most common)
  • Angiodysplasia
  • Ischemic colitis
  • Hemorrhoids
  • IBD
  • Neoplasia

Management

  • Unstable:
    1. IV resuscitation
    2. Colonoscopy/CT angiogram
    3. Radiological embolization
  • Stable: Consider discharge if:
    • Age <60
    • No hemodynamic disturbance
    • No gross rectal bleeding
    • Not on NSAIDs/anticoagulants

Vomiting

Causes of Vomiting by System
System Causes
GI Tract Gastroenteritis, GERD, Acute abdomen, Bowel obstruction
Nervous System Motion sickness, Vertigo, ICH, Migraine, Raised ICP
Endocrine Hyper/hypoglycemia, Hypercalcemia, Uremia, Adrenal insufficiency
Pregnancy Morning sickness, Hyperemesis gravidarum
Drugs Alcohol, Opiates, SSRIs, NSAIDs, Chemotherapy
Anti-emetic Classes
Class Examples Indications
Phenothiazines Prochlorperazine Nausea/vomiting (blocks dopamine)
Prokinetics Metoclopramide Gastric paresis, GERD
5-HT3 antagonists Ondansetron Post-op, Chemotherapy

Diarrhea

Definition: Loose/liquid stools >3x/day or >200g/day

Acute (<4 weeks) vs Chronic (>4 weeks)

Infectious Diarrhea Causes
Type Organism Clues
Bloody Campylobacter Guillain-Barré association
E. coli 0157:H7 HUS risk
Salmonella Chicken/eggs
Non-bloody Rotavirus Daycare settings
Staph aureus Mayonnaise foods
Norovirus Cruise ship outbreaks

C. difficile Management

  • Risk factors: Clindamycin, FQs, Cephalosporins
  • Treatment:
    • Vancomycin 125mg QID (WBC <15k)
    • Fidaxomicin 200mg BD (WBC >15k)

Liver Disease

LFT Patterns
Type Bilirubin ALT/AST ALP/GGT
Hepatocellular ↑Unconjugated ↑↑ (AST>ALT in EtOH) Normal/mild ↑
Cholestatic ↑Conjugated Normal/mild ↑ ↑↑

Acute Liver Failure

Causes: Paracetamol, Drugs, Viral hepatitis, Toxins

Management:

  • ABCDE approach
  • Lactulose/enemas
  • N-acetylcysteine for paracetamol
  • Avoid sedatives/opiates

Biliary & Pancreatic Disorders

Acute Pancreatitis

Causes (GET SMASHED): Gallstones, EtOH, Trauma, Steroids, Mumps, Autoimmune, Scorpion venom, Hyperlipidemia, ERCP, Drugs

Ranson's Criteria: ≥3 predicts severe pancreatitis

Ascending Cholangitis

Charcot's Triad: Pain, Jaundice, Fever

Management: IV fluids, broad-spectrum antibiotics, urgent ERCP