Disorders of Renal Function Flashcards
What is acute renal failure caused by?
conditions that produce an acute shutdown in renal function
decreased in blood flow, ischemia, toxic, obstructive tubular injury, obstruction of urinary tract outflow
Is acute renal failure reversible?
it is potentially reversible if the factors causing the condition can be corrected
What is the most common indicator of Acute Renal Failure?
Azotemia
-abnormally high levels of nitrogen-containing compounds (such as urea, creatinine, various body waste compounds, and other nitrogen-rich compounds) in the blood
Why is azotemia an indicator of Acute Renal Failure?
because it is largely related to insufficient filtering of blood by the kidneys
What are other indicators of Acute Renal Failure?
decrease in GFR (glomerulus filtration rate), accumulation of nitrogenous wastes, and an alteration in body fluids and electrolytes
What is the most common type of Acute Renal Failure?
Prerenal Failure (something happens in the system before the kidney)
What are the causes of Prerenal Failure?
causes Acute Renal Failure by a decrease in renal blood flow (e.g. hypovolemia, hypotension, hemorrhage, plasma volume deficit, water and electrolyte loss, cardiac failure or shock, massive pulmonary emboli, interruption of renal artery flow
Where does Intrarenal Failure occur?
Acute Tubule Necrosis - in the actual kidney itself
What are the causes of Intrarenal Failure?
- conditions that cause damage to structures within the kidney
e. g. : prolonged renal ischemia, Nephrotoxins (drugs like NSAIDs), Glomerulopathies (infection), intratubular obstructions or necrosis, bilateral pyelonephritis
What is Acute Tubule Necrosis (ATN)?
Destruction of the tubular epithelial cells (inside the kidney) with acute suppression of renal function
Tubular epithelial cells are particularly SENSITIVE to ischemia and toxins
Ischemic ATN occurs most frequently in who?
in persons who have major surgery, severe hypovolemia, overwhelming sepsis, trauma and burns
Is ATN reversible?
Can be reversible if detected early enough and treated appropriately. If untreated can lead to chronic kidney disease. (does take time to regenerate/heal the tissue, not going to happen quickly)
What are the 3 phases of ATN?
- Initiation
(acute drop in GFR , rise in BUN/Creatinine) - Maintenance
(Oliguria (no urine… will cause edema), SEVERE decrease in GFR, rise of BUN/creatinine) - Recovery
(function restored, Diuresis, labs normalize)
*small fraction don’t recovery
What do we need to do with patients in the recovery stage of ATN?
make sure they get plenty of water dehydration from Diuresis they experience.
Why do patients in the recovery stage of ATN experience Diuresis?
“because kidneys can now work and they get excited and work overtime “ - paraphrase of Ms. Schneider
What do we worry about during the maintenance stage of ATN?
Respiratory status because of the edema from oliguria (no urine output)
What else do the kidneys do beside filtration?
erythropoietin to stimulate RBC manufacturing
What is Chronic Kidney Disease (CKD)?
progressive and irreversible destruction of kidney structures and renal endocrine functions
progressive decline in kidney function due to permanent loss of nephrons
What are the primary causes of CKD?
diabetes and uncontrolled HTN
What are the 4 stages of CKD based on GFR?
- Diminished renal reserve
- Renal insufficiency - (renal function is dropping off, don’t need dialysis yet)
- Renal Failure
- End-stage renal disease
What are the CLINICAL manifestations of CKD?
increase or decrease Sodium : impaired Na+ regulation
Increase Potassium: impaired excretion (held on to)
increase Phosphate: impaired excretion (held on to)
Decrease Calcium (hypocalcemia): phosphate binds to Ca+ (brittle bones, retardation of growth/Gary Coleman)
Decrease RBC (anemia): decrease erythropoietin production
Decrease pH (metabolic acidosis): impaired buffering
increase volume overload
What do we need to remember when checking the electrolyte levels in the blood?
the volume of the blood can affect the reading (too little volume will increase the numbers and make it look elevated even though it may actually be within normal range)
What are the Manifestations of CKD?
Hypertension (renin-angiotensin-aldosterone system)
Azotemia
Uremia
What is Azotemia?
accumulation of nitrogenous wastes in the blood
