Objective 69: How water excess and dehydration affect kidney function

On page 873 figure 25.7 details water excess and dehydration.  I use this to try and relate it to the kidney's function.  I know fluid excess is less common than dehydration. This is because the kidneys are very effective at compensating for excessive fluid intake, by producing more urine. This is one of the main functions of the kidneys. When the kidneys are not functioning properly, however, this usually leads to excessive fluid retention. In the case of dehydration, the volume of fluid in the intravascular space decreases, and blood pressure may fall. This can decrease blood flow to the kidneys, and like any organ with a decreased blood flow; it has the potential to fail to do its job.