Net filtration pressure equation
How do you calculate net filtration pressure?
Or: NFP = 55 – [15 + 30] = 10 mm Hg (Figure 25.4. 1). Figure 25.4. 1 – Net Filtration Pressure: The NFP is the sum of osmotic and hydrostatic pressures.
What is the net filtration pressure?
The net filtration pressure (NFP) represents the interaction of the hydrostatic and osmotic pressures, driving fluid out of the capillary. It is equal to the difference between the CHP and the BCOP. Thus, the NFP of 10 mm Hg drives a net movement of fluid out of the capillary at the arterial end.
What is pressure filtration in the kidneys?
The process by which glomerular filtration occurs is called renal ultrafiltration. The force of hydrostatic pressure in the glomerulus (the force of pressure exerted from the pressure of the blood vessel itself) is the driving force that pushes filtrate out of the capillaries and into the slits in the nephron.
How does pressure affect filtration rate?
The glomerular filtration rate is directly proportional to the pressure gradient in the glomerulus, so changes in pressure will change GFR. GFR is also an indicator of urine production, increased GFR will increase urine production, and vice versa.
What increases Net filtration pressure?
An increase in the afferent arteriolar diameter (decrease in resistance) causes an increase in the glomerular capillary hydrostatic pressure and an increase in GFR. A decrease in the diameter of the afferent arteriole has the opposite effect.
When the net filtration pressure is negative?
(B) A negative net filtration pressure refers to a condition that favors the movement of fluid out of the capillary lumen and into the surrounding interstitial fluid (i.e., fluid filtration out of the capillary).
What is effective filtration pressure?
Effective filtration pressure (EFP) refers to the net driving forces for water and solute transport across the glomerular membrane.
What three driving forces determine glomerular filtration rate?
glomerular filtration rate (GFR) – The total amount of plasma filtrate formed by all the nephrons of the kidneys per minute; it is determined physiologically by three factors: (1) the total surface area available for filtration, (2) the permeability of the filtration membrane, and (3) the net filtration pressure;
What are the three factors that regulate glomerular filtration rate?
Three factors regulate glomerular filtration rate (GFR). These three factors are decrease in systemic blood pressure, normal systemic blood pressure, and increase in systemic blood pressure.
What are the three processes of urine formation?
Urine formation occurs during three processes:Filtration.Reabsorption.Secretion.
What is a filtrate?
: fluid that has passed through a filter.
How is filtration used by humans?
Your kidneys sit on each side of the spine underneath the rib cage and look like two bean-shaped organs, each the size of a human fist. These organs are important not only as filters, but also for balancing the body’s natural acid, potassium, and salt contents. Kidneys filter waste and toxins out of the blood.
What happens if glomerular filtration rate is too high?
The kidneys have mechanisms designed to preserve GFR within a certain range. If GFR is too low, metabolic wastes will not get filtered from the blood into the renal tubules. If GFR is too high, the absorptive capacity of salt and water by the renal tubules becomes overwhelmed.
What can I do to improve GFR?
Avoid processed foods and choose fresh fruits and vegetables instead. It’s important to follow a low-salt diet. Salt should be limited especially if you have high blood pressure, protein in your urine, or swelling or difficulty breathing. Eating less than 2000 mg a day of sodium is recommended.