Disorders in Digestive System

Acid and Electrolytes Balance in Vomiting and Diarrhoea

Learning Objectives

Understand:

  • Acid and electrolytes balance in vomiting and diarrhoea

  • Common causes of GIS disorders

  • The classical locations and abdominal pain patterns of different GIS disorders

  • Tissue damages in GIS disorders

  • Special diagnostic tests for GIS disorders

  • The principles of management

Common Symptoms of GIS Disorders

  • Pain, location based on regions: Upper right, Upper left, Lower right, Lower left, Epigastric, Periumbilical, Pelvic.

  • Loss of appetite

  • Vomiting: assesses fluid and nutrition status

  • Diarrhoea: assesses frequency, consistency, and color

  • Constipation

  • Maldigestion and malabsorption: assesses nutrition

Pain Localization and Possible Conditions

Various conditions can be indicated based on pain location. Examples include:

  • Epigastric region: Gastroesophageal reflux, Inflamed stomach, Peptic ulcer

  • Right upper quadrant: Hepatitis, Fatty liver disease, Inflamed gall bladder, Gall stone

  • Lower right quadrant: Appendicitis

  • Periumbilical region: Food poisoning, IBS

  • Inflamed large intestine

  • Haemorrhoids

Appendix and Appendicitis

The appendix's position can vary. Key diagnostic indicators include:

  • McBurney point tenderness

  • Rebound tenderness

  • Rovsing's sign

Statistics:

  • 64% of appendices are in a typical position.

  • 0.5% are located posteriorly.

Referred Abdominal Pain

Pain can be referred from various organs:

  • Heart

  • Liver

  • Small intestine

  • Colon

  • Rectum

  • Kidney

  • Ureter

Examples:

  • Biliary colic

  • Renal colic

Conditions referring pain:

  • GERD

  • Peptic ulcer

  • Pancreatitis; Perforated duodenal ulcer; Penetrating duodenal ulcer

  • Cholecystitis

  • Appendicitis

  • Ureteral colic

  • Rectal lesions

Oesophagus and Stomach

  • Sphincter: A ring-shaped muscle that relaxes or tightens to open or close a passage.

  • Gastroesophageal sphincter (cardioesophageal sphincter): A physiological sphincter with slight thickening where the oesophagus meets the stomach.

  • Acidic environment of the stomach has a pH of approximately 22. Functions include activating pepsinogen, denaturing proteins, and killing bacteria. The gastric mucosal barrier protects the stomach lining.

Gastroesophageal Reflux (GERD)

  • Reflux of chyme (partially digested food) from the stomach into the oesophagus.

  • The oesophageal mucosa is repeatedly exposed to acids and enzymes (pepsin) in the chyme.

  • Cause: Increased abdominal pressure (vomiting, coughing, lifting, bending) and delayed gastric emptying (peptic ulcers, narrowing of pyloric sphincter).

  • Diagnosis: Clinical symptoms (regurgitation of acid chyme, upper abdominal pain within 1 hour of eating, heartburn) and endoscopy.
    An important differential diagnosis is ruling out other sources of chest pain (e.g., MI)

  • Inflammatory Responses: Oedema, tissue fragility, erosion, fibrosis & thickening may develop, potentially leading to reflux esophagitis.

  • Treatment: Antacids to neutralize gastric contents, smooth muscle stimulants to increase the rate of gastric emptying, surgery to narrow the gastroesophageal sphincter, and lifestyle changes (reducing fatty and fried food, limiting eating at night).

Peptic Ulcer Disease

  • A break or ulceration in the protective mucosal lining due to exposure to acid-pepsin secretions.

    • Superficial ulcers (erosion): Erode only the mucosa.

    • True ulcers: Erode through the muscularis mucosae, or even deeper into the submucosa or muscularis.

  • True ulcers can damage blood vessels causing haemorrhage or perforate the gastrointestinal wall.

  • Two common types: Duodenal and gastric.

  • Risk Factors: Long-term use of NSAIDs (aspirin, ibuprofen), Helicobacter (H.) pylori infection, alcohol, smoking, traumatic events (e.g., burns, stroke).

Duodenal Ulcers

  • Most common type of peptic ulcer.

  • More common in the age group 20-50 and in men.

  • The primary defect is hypersecretion of acid & pepsin.

  • Symptoms: Chronic intermittent pain in the epigastric area, empty stomach pain (2-3 hours after eating or in the middle of the night), a