Question

While treating burn patients. Megan, a recently graduated RN, notices that they contain increased levels of potassium in their urine. Explain why Megans patients are experiencing the symptoms?

Answer 1

Burns cause tissues to release cytokines. These cytokines dilate the vessels. Therefore there occurs increased evaporation of fluids and vessels become leaky and start to loose albumin to the interstitium. this increases the colloid osmotic pressure in interstitium and decrease the colloid osmotic pressure in capillaries. Hence the fluid is pulled by the interstitium from the capillaries. Therefore the blood volume decreases which is called hypovolemia. In response to hypovolemia, aldosterone is released in excess amounts. Aldosterone acts on P cells of collecting tubules of nephron and cause increased reabsorption of sodium and water and increased excretion of potassium into the urine. Sodium and water reabsorbed increase the blood volume and increased level of potassium is found in the urine.