A patient with chronic liver failure has a low serum albumin and bilateral ankle oedema. The primary Starling force responsible for maintaining plasma oncotic pressure and preventing oedema is:
- A Plasma colloid osmotic pressure (oncotic pressure) ✓
- B Capillary hydrostatic pressure
- C Interstitial fluid pressure
- D Lymphatic flow rate
Correct answer: A. Plasma colloid osmotic pressure (oncotic pressure)
Explanation
Plasma colloid osmotic pressure (approximately 28 mmHg, predominantly generated by albumin) opposes capillary filtration and keeps fluid in the vascular compartment. In liver failure, albumin synthesis falls, reducing plasma oncotic pressure and tipping the Starling balance toward filtration and oedema formation. Capillary hydrostatic pressure favours filtration; interstitial fluid pressure and lymphatics are secondary safety factors.
Reference: Guyton & Hall, Textbook of Medical Physiology, 14th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
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