Abdominal Anatomy and Assessment

Structure and Function of the Abdomen

  • The abdomen is a large, oval cavity that extends from the diaphragm down to the brim of the pelvis.
  • The internal organs within the abdominal cavity are referred to as viscera.
  • The abdominal wall is lined by the peritoneum, which covers most abdominal organs.

Abdominal Quadrants

  • The abdomen is divided into four quadrants by vertical and horizontal lines crossing at the umbilicus:
    • Right Upper Quadrant (RUQ):
    • Contains the liver, gallbladder, duodenum, head of the pancreas, right kidney & adrenal gland, hepatic flexure of the colon, part of ascending and transverse colon.
    • Left Upper Quadrant (LUQ):
    • Contains the stomach, spleen, left lobe of the liver, body of the pancreas, left kidney & adrenal gland, splenic flexure of the colon, part of transverse and descending colon.
    • Right Lower Quadrant (RLQ):
    • Contains the cecum, appendix, right ureter, right ovary & fallopian tube (in women), or right spermatic cord (in men).
    • Left Lower Quadrant (LLQ):
    • Contains part of the descending colon, sigmoid colon, left ureter, left ovary & fallopian tube (in women), or left spermatic cord (in men).

Midline Structures

  • The midline structures include the aorta, bladder (if distended), and uterus (if enlarged in women).
  • In neonates, the urinary bladder is positioned higher between the symphysis and umbilicus than in adults.

Abdominal Assessment Considerations

Age-Related Changes:
  • Infants and Children:
    • Abdominal wall is less muscular for easier palpation.
    • Assess breastfeeding/bottle-feeding, introduction of new foods, eating habits, bowel habits, weight, and abdominal pain.
  • Pregnant Women:
    • May experience morning sickness due to hCG changes.
    • Additional effects: acid indigestion, constipation, striae, and linea nigra.
  • Aging Adults:
    • Fat deposits increase in suprapubic and abdominal areas.
    • Changes include decreased salivation, delayed esophageal emptying, reduced gastric acid secretion, increased incidence of gallstones, and shrunk liver size.

Relevant Medical Conditions

  • Lactose Intolerance:
    • Symptoms include abdominal pain, bloating, and flatulence.
  • Celiac Disease:
    • An autoimmune disorder causing permanent gluten intolerance.

Subjective Assessment

  • Inquire about:
    • Appetite and dysphagia
    • Food intolerances
    • Abdominal pain
    • Nausea and vomiting
    • Bowel habits
    • Past abdominal history
    • Current medications
    • Nutrition

Objective Assessment

  • Ensure the abdominal wall is relaxed and bladder is empty.
Examination Sequence:
  1. Inspection:
    • Note contour, symmetry, shape of umbilicus, skin condition, pulsations, pubic hair pattern, and demeanor.
  2. Auscultation:
    • Listen for bowel sounds and potential vascular sounds or bruits before percussion/palpation (to prevent increased peristalsis).
  3. Percussion:
    • Assess density of abdominal contents; perform fluid wave and shifting dullness tests to check for ascites.
  4. Palpation:
    • Judge size, location, and consistency of organs, checking for abnormal masses or tenderness using light and deep palpation.
    • Specific tests for appendicitis:
      • Blumberg sign
      • McBurney point tenderness
      • Iliopsoas muscle test
      • Obturator test
      • Alvarado/MANTRELS score
  • Infants: Assess skin condition, bowel sounds, and abdominal contents.

Health Promotion

  • Educate patients on Hepatitis B and C, including prevention strategies for these diseases.