Basic Renal Anatomy and Renal Processes Questions

1. Kidney stones occur when solid material blocks the flow of urine in the renal system.If left untreated,

kidney stones can lead to renal failure. You are a Nephrologist treating a patient who has already

had one kidney removed. The patient is experiencing nausea, vomiting, and swelling of the

extremities (edema.) An MRI shows a kidney stone that has completely blocked the ureter of the

remaining kidney. Please explain how the kidney stone would lead to the patient’s edema.

In answering this question, walk your way through the following logic:

A. Consider the anatomy of the renal system; blocking the ureter would mean fluid backs up where?

B. Which of the factors that determines NFP of the glomerular capillaries would be affected by the

back-up? How would that factor change (increase/decrease)?
C. How would NFP of the glomerular capillaries change? Would this mean more/less fluid stays in

the blood? Use the NFP equation (glomerular capillary version) to defend your answer!

D. If more/less fluid stays in the blood (as you indicated in part 3,) how would that change P H of

the systemic capillaries?

E. How would NFP of the systemic capillaries change? Why would this cause edema? Use the NFP

equation (systemic capillary version) to defend your answer!

2. Let’s make sure we have the basics down first…

ˆ What is the physiologically normal value of blood/ECF pH? If a patient were acidotic, how

would their pH change? If a patient were alkalotic, how would their pH change?

ˆ What are the physiologically normal values for blood/ECF P CO2 and bicarbonate?

ˆ What is the difference between an acid-base disturbance of respiratory vs. metabolic origin?

ˆ If a patient has a respiratory acid-base disturbance, will their body try to compensate using

respiratory or metabolic mechanisms? How about for a metabolic acid-base disturbance?

ˆ If a patient is acidotic, and their body partially compensates for the disturbance, in which

direction will their pH change? How about for a partially-compensated alkalosis?

ˆ How do we know if a patient has fully compensated for an acid-base disturbance?