* Scenario A:
* Acute renal failure. Ms. Jones, a 68-year-old female, underwent open-heart surgery to replace several blocked vessels in her heart. On her first day postoperatively, it was noted that she had very little urine output. *
* 1. What is happening to Ms. Jones’s kidneys, and why is it causing the observed symptom? Usually the kidney manages its own blood flow and GFR. When the kidneys become hypoperfused, such as in hypovolemia, heart failure, shock, the renal arteries narrowing, the kidney vessels enlarge with the assistance of prostaglandins to ease flow. If this auto regulation of blood flow is unsuccessful, the GFR can be controlled by choosy limitations of post-glomerular (efferent) arteriole by the discharge of rennin and generation of angiotensins II. Continuous hypoperfusion of the kidneys may lead to the malfunction of these offsetting devices and a severe drop in GFR. Renal tubules develop into hyper functional and re-absorption of sodium and water is greater than before, through the importance of angiotensins, aldosterone and vasopressin. This leads to the development of a small amount of urine which is reduced. * 2. What other symptoms and signs might occur?
Acute renal malfunction does not create a standard set of symptoms. The most frequent symptom is lower urine amount produced, which happens in 70% of patients. Additional signs and symptoms could be those due to toxicity, shock or hypovolemia, such as fever and lightheadedness. * 3. What is causing Ms. Jones’s kidney disease?
Ms. Jones is encountering acute tubular necrosis (ATN). It is a renal cause of ARF. Essentially tubular cells in the tubule of the kidney are dying.