Key messages

• The fluid exchange between parenchymal cells and extracellular fluid is determined by the ionic imbalance across the cell membranes.

• The fluid exchange between plasma and interstitial space is related to the existing capillary pressure, the tissue fluid pressure, the oncotic (protein osmotic) pressure of plasma and tissue fluids, and the permeability of the capillary endothelial barrier.

• The forces operating across the capillary walls are almost balanced, and the small amount of fluid that enters the interstitium is removed by the lymphatics.

• Interstitial edema occurs when the capillary pressure is increased or the endothelial barrier is damaged and fluid containing protein enters the tissue in amounts that cannot be removed by the lymphatics, and excessive fluid accumulates in potential tissue spaces.

• Interestingly, when capillary pressure increases to 25 to 30 mmHg, little fluid enters the interstitium because tissue fluid pressure is increased, the protein osmotic pressure gradient acting across the capillary wall decreases, and lymph flow decreases. These changes, which oppose capillary filtration, are edema safety factors.

Sleep Apnea

Sleep Apnea

Have You Been Told Over And Over Again That You Snore A Lot, But You Choose To Ignore It? Have you been experiencing lack of sleep at night and find yourself waking up in the wee hours of the morning to find yourself gasping for air?

Get My Free Ebook

Post a comment