Makindo Medical Notes

About

The chest and abdomen house vital organs responsible for respiration, circulation, digestion, and excretion. These regions are separated by the diaphragm, a dome-shaped muscle critical for breathing.

Chest Anatomy

• Thoracic Cage:
  • Composed of the sternum, ribs, and thoracic vertebrae.
  • Protects the heart, lungs, and great vessels.
  • Provides attachment points for muscles involved in respiration and upper limb movement.
• Lungs:
  • Paired organs responsible for gas exchange (oxygen and carbon dioxide).
  • Right lung has three lobes (upper, middle, lower); left lung has two lobes (upper, lower) and a cardiac notch.
• Heart:
  • Located in the mediastinum and enclosed by the pericardium.
  • Pumps oxygenated blood to the body and deoxygenated blood to the lungs.
  • Supplied by the coronary arteries.
• Major Vessels:
  • Aorta: Largest artery, delivers oxygenated blood from the heart to the body.
  • Superior and Inferior Vena Cava: Return deoxygenated blood to the heart.
  • Pulmonary Arteries and Veins: Carry blood between the heart and lungs.
• Diaphragm:
  • Primary muscle of respiration, separating the thoracic and abdominal cavities.
  • Innervated by the phrenic nerve (C3-C5).

Abdomen Anatomy

• Abdominal Wall:
  • Composed of layers (skin, muscles, fascia) that protect abdominal organs.
  • Key muscles: Rectus abdominis, external oblique, internal oblique, transversus abdominis.
• Gastrointestinal Tract:
  • Esophagus: Connects throat to the stomach.
  • Stomach: Responsible for mechanical and chemical digestion.
  • Small Intestine: Includes duodenum, jejunum, ileum; main site for nutrient absorption.
  • Large Intestine: Includes cecum, colon, rectum; absorbs water and forms feces.
• Liver:
  • Largest internal organ, processes nutrients, detoxifies, and produces bile.
  • Located in the right upper quadrant.
• Gallbladder:
  • Stores and concentrates bile for fat digestion.
• Pancreas:
  • Exocrine function: Produces digestive enzymes.
  • Endocrine function: Produces insulin and glucagon to regulate blood sugar.
• Kidneys:
  • Filter blood, regulate electrolytes, and produce urine.
  • Located retroperitoneally in the upper abdomen.
• Spleen:
  • Filters blood, removes old red blood cells, and plays a role in immunity.
  • Located in the left upper quadrant.
• Bladder:
  • Stores urine before excretion through the urethra.
  • Located in the pelvis.

Clinical Significance

• Thoracic Cavity: Pathologies include pneumonia, pleural effusion, pneumothorax, and heart disease.
• Abdomen: Common issues include appendicitis, gallstones, hernias, and kidney stones.
• Knowledge of anatomy is crucial for imaging, surgery, and understanding referred pain patterns.