Renal Labs 2 Schoenwald Flashcards
If free water is increased, what happens to the sodium?
It is diluted and levels decrease (less concentrated)
If free water is decreased, what happens to the sodium?
It is concentrated and levels increase (more concentrated)
What is osmolality?
Measures the amt of dissolved particles in the blood to determine hydration status
Osmolality _______ with overhydration and ________ with dehydration
decreases, increases
What is the purpose of ADH?
It regulates body water and osmolality so when there is an increased osmolality = dehydration = ADH stimulated so we hold onto water
What is SIADH?
Syndrome of inappropriate ADH
-This causes the body to retain too much water and leads to decreased serum sodium
What is diabetes insipidus?
Opposite of SIADH
-Inadequate amt of ADH present so symptoms are increased passage of large volumes of dilute urine leading to hypernatremia
SIADH causes sodium levels to ______ whereas diabetes insipidus causes sodium levels to ________
decrease, increase
This evaluates the ability of the kidney to concentrate urine and is more accurate than specific gravity
urine osmolality
What is urine osmolality?
Basically the amount of particles concentrated in the urine
Urine osmolality is increased in what two conditions?
- SIADH
- CHF
Urine osmolality is decreased in what two conditions?
- Diabetes insipidus
- Excess fluid intake
What are two types of hyponatremia?
- Sodium depletion (free water loss)
- Water intake > water output- renal failure
Hyponatremia causes what three symptoms?
Muscle cramps, nausea, lethargy
-Cerebral edema b/c not enough sodium to keep water in its space
Symptoms of hypernatremia are…
dehydration
To test sodium levels, what test do we use?
24 hour urine or spot testing
Once you determine hyponatremia from a urine test, what is the next step?
Order a serum osmolality to tell tonicity status of hyponatremia
What are some causes of hypovolemic hyponatremia <10?
- Dehydration
- Diarrhea
- Vomiting
What are some causes of hypovolemic hyponatremia <20?
Renal salt loss
What are some causes of euvolemic hyponatremia?
SIADH and postop hyponatremia
What are some causes of hypervolemic hyponatremia?
= edema
- CHF
- Advanced renal failure
- Liver disease
Sodium is primairly a _______ cation
circulating (extracellular space)
Potassium is primarily an _______ cation
intracellular
As sodium is reabsorbed, _____ is lost
potassium
When you are on furosemide and lasix, what else should you supplement with?
K+ because you pee out K+ when taking these meds
EKG findings of this include flattened or inverted T waves
Hypokalemia
EKG findings of this include peaked T waves
Hyperkalemia
Hyperkalemia is associated with what two things?
Renal failure and acidosis
Symptoms of this cause malaise, skeletal mm weakness and arythmias
Hypokalemia
Symptoms of this cause arrythmias and cardiac arrest, numbness, tingling and weakness
Hyperkalemia
This is the most abundant extracellular anion
Chloride
Chloride is regulated by the renal proximal tubules and exchanged for ______ ions
bicarb
If Na increases, what happens to the Cl?
It also increases
This is a condition in which there is a rapid deterioration of kidney function and accumulation of nitrogenous wastes?
Acute renal failure
Is Acute renal failure reversible?
Yes
Symptoms of this disease include nausea, vomiting, AMS and edema
Acute renal failure
Causes of prerenal ARF?
- **CHF
- Hypovolemia
- Hypotension
- Renal artery stenosis
Causes of renal ARF?
- nephrotoxins
- autoimmune diseases
Causes of postrenal ARF?
-Obstruction
ARF is an increase in serum Cr by ____5 over baseline levels
50%
The RIFLE classification is used to stratify the severity of acute kidney injury. What does it stand for?
Risk Injury Failure Loss End stage
What is the RIF in the RIFLE criteria and what happens to the Creat or GFR?
- Risk = inc Cr 1.5x or GFR > 25% decrease from baseline
- Injury = inc Cr 2.0x or GFR > 50% decrease from baseline
- Failure = inc Cr 3.0x or Cr >4 with acute increase >0.5 or GFR > 75% decrease from baseline
What stage CKD is this?
Kidney damage with normal GFR >90 mls/min
Stage 1
What stage CKD is this?
Kidney damage with mild decrease in GFR 60-89 mls/min
Stage 2
What stage CKD is this?
Moderate decrease GFR 30-59 mls/min
Stage 3
A BUN/Cr ratio of <15:1 = renal or prerenal cause?
renal
A BUN/Cr ratio of >20:1 = renal or prerenal cause?
prerenal cause
What are the two mc causes of chronic renal failure?
DM and HTN
CO2 = acid- regulated by the ____
lungs
Bicarb= base- regulated by the ______
kidneys
