Final answer:
Glomerular Filtration Rate (GFR) is a vital measurement to assess kidney function, particularly in filtering blood. It is pivotal in determining the correct dosages of medications excreted by the kidneys and in diagnosing kidney health. Hydrostatic pressure, colloid osmotic pressure, and creatinine clearance are key factors influencing GFR.
Step-by-step explanation:
GFR is a critical index used to assess the excretory function of the kidneys. It helps determine how well the kidneys are filtering blood and is essential for diagnosing and managing kidney-related diseases. The average GFR for healthy individuals is approximately 90-120 mL/min/1.73m2. The measurement of GFR is instrumental for the correct dosage of medications that are primarily excreted via the kidneys.
Hydrostatic pressure and colloid osmotic pressure are two opposing forces involved in glomerular filtration. Under normal conditions, hydrostatic pressure is greater, allowing filtration to occur. The body's filtration rate is autoregulated, ensuring that kidneys function over a range of blood pressures.
To assess GFR accurately, substances like inulin or creatinine are used. Inulin, a plant polysaccharide, is neither reabsorbed nor secreted by the kidneys, making it a perfect marker for measuring GFR. On the other hand, creatinine clearance is often used since it's naturally occurring and easier to measure in a clinical setting. Nevertheless, a decline in GFR can lead to the accumulation of drugs that are normally cleared by healthy kidneys, posing a potential toxicity risk.
A reduction in GFR can lead to kidney failure, with symptoms including an inability to concentrate urine during fluid restrictions, reflecting a reduction in water reabsorption. Dilution and concentration tests, as well as examining urine osmolality, assist in assessing kidney function regarding fluid regulation.