Shoeny Renal 2 Flashcards
What’s in an electrolyte panel? Whats the main regulator of electrolytes?
Na, K, Cl, CO2
Kidney is the main regulator of water and sodium.
What has a normal level of 136-145mEq/L, is the primary ciruclating cation, and is needed for neuromuscular function?
Na+
Serum balances of Na+ are the balance between _________ & ________
Dietary intake and renal excretion
What is sodium an indicator of?
Free body water, it is the major contributer to plasma osmolality.
If free water is increased, Na is diluted and levels decrease
If free water is decreased, Na is concentrated and levels are increased
What is Osmolality?
It is a measure of concentration of dissolved particles in the blood. Useful in the setting of hyponatremia, evaluating ADH related illness
As amount of free water increases amount of particles _____. Osomolality ________
Decrease, decrease
As amount of free water decreases, amount of particles _______, osmolalitly ______
increases, increases
Osmolality decreases with ________ and increases with _______
osmolality decreases with overhydration and increases with dehydration.
What does ADH do? What is it stimulated by?
ADH regulates body water and osmolality
Stimulated by increased osmolality, hypovolemia, thirst.
ADH acts on the collecting tubule to increase permeability = increase water reabsorption - more concentrated urine.
In hypernatremia, hyperglycemia, ketosis, dehydration, diabetes insipidus, osmolality is?
Increased
In overhydration and syndrome of inappropriate ADH osmolality is?
Decreased
What is syndrome of inappropriate ADH?
Abnormally high amount of ADH present.
Leads to increased water reabsorption leading to decreased serum sodium levels and loss of sodium in the urine.
Drugs are common cause
What is diabetes insipidus? What are the symptoms?
Inadequate amount of ADH present. Symptoms are increased thirst and passage of large volumes of dilute urine.
What electrolyte imbalance is present in diabetes insipidus?
Hypernatremia
What does urine osmolality measure? What does it evaluate about the kidney?
Measures dissolved particles in the urine - more accurate than specific gravity.
Evaluates ability of kidney to concentrate urine.
Normal is 50-1200 mOsm/kg H20
Urine osmolality would be _______ in SIADH
Increased
Urine osmolality would be ________ in diabetes insipidus and excess fluid intake.
Decreased.
What are the two types of hyponatremia?
Sodium depletion - free water loss
Dilutional- water intake greater than water output - renal failure.
What are symptoms of hyponatremia?
Asymptomatic until <120
Symptoms include lethargy, nausea, muscle cramps
Cerebral edema.
Hypernatremia is a sodium level above what? When would this be present?
Above 145. Present in impaired thirst mechanism (stroke), or water loss without sodium loss (burns), fever, and dehydration.
What is urine sodium helpful for?
Helpful for distinguishing between renal and nonrenal causes of hyponatremia.
Urine sodium would be _______ in dehydration, diuretic therapy, Adrenocortical insufficiency, SIADH, Chronic renal failure.
Increased.
Urine sodium would be _____ in CHF and diarrhea.
decreased.
How do you initially evaluate hyponatremia?
Look at volume status of the patient. Is the patient hypovolemic? Euvolemic? Or Hypervolemic?
OR
Look at osmolality. Does patient have normal, low or high osmolality levels?
Is someone is hypovolemic and hyponatremic what could be some causes?
Dehydration, diarrhea, vomiting if UNa is less than 10
Renal salt loss is UNa is greater than 20
If a patient is euvolemic and hyponatremic. What could be causes?
SIADH
Postop hyponatremia.
If a patient is hypervolemic but has hyponatremia, would could be a cause?
CHF
Advanced renal failure
Liver disease
If a patient is hyponatremic but has normal osmolality what could be a cause?
Isotonic hyponatremia
Hyperporteinemia
Hyperlipidemia
If a patient is hyponatremic and has low osmolality whats the cause?
Hypotonic hyponatremia
High osmolality and hyponatremia causes?
Hypertonic hyponatremia
Hyperglycemia
Radiocontrast agents.
What ion has a normal value of 3.5-5.5, is a primary intracellular cation, and the function of cardiac muscle depends on it?
K+
Minor changes in concentration of K+ have no consequeneces. T/F
False - minor changes in concentration have significant consequences.
Is potassium reabsorbed the kidneys?
No reabsorption, potassium is excreted.
Hypokalemia is potassium below what level? What are the s/s.
K below 3.5
s/s- malaise, skeletal mm weakness, arrythmias
What EKG change is associated with hypokalemia?
EKG flattened or inverted T waves.
Deficient dietary intake, diuretic usage, burns, glucose administration, licorice ingestion, aldosterone excess can cause what?
Hypokalemia
Hyperkalemia is associated with levels above what? What are s/s
K> 5.5
Symptoms include arrythmias and cardiac arrest, numbness, tingling, weakness.
What disease is associated with hyperkalemia?
Renal failure and acidosis
K+ is driven out of the cell.
What EKG change would you see in hyperkalemia?
Peaked T waves.
Causes of hyperkalemia?
Excessive dietary intake
ACE inhibitors
Acute or chronic renal failure
Hemolysis.
What ion has a normal value of 96-106, is the most abudant extracellular anion, and is indirectly regulated by Na and H20?
Chloride.
Chloride is regulated by?
Regulated by renal proximal tubules and exchanged for bicarb ions.
Chloride would ________ in dehydration and metabolic acidosis
Increased
Chloride would be _________ in overhydration, SIADH, Vomiting.
Decreased
What does acute renal failure lead to accumulation of?
This is rapid deterioration of kidney function, which leads to accumulation of nitrogenous wastes.
Most common cause of acute renal failure? Prerenal cause?
Nephrotoxins - medications. -MC
Prerenal causes - hypoperfusion.
Symptoms of ARF? Is this reversible?
N/V, change in mental status, edema.
Reversible in most cases
Prerenal causes of ARF?
Hypovolemia, hypotension, CHF, Renal artery stenosis
Renal causes of ARF?
Nephrotoxins, Autoimmune diseases.
Post renal cause of ARF?
Obstruction.
Acute kidney injury is an acute increase in serum creatinine of ________ or more than ______ over baseline levels?
>0.5 mg/dl or more than 50% over baseline levels.
What is the key parameter for renal function management? What are less reliable but still can be used?
GFR - glomerular filtration rate.
BUN and creatinine are less reliable than GFR but can be easily measured.
In the RIFLE classification an increase of creatinine of 1.5x or GFR decrease of 25% from baseline would be what category?
Risk of injury
In the RIFLE classification an increase of creatinine 2x or GFR decrease of 50% or more from baseline would be what category?
Injury
In the RIFLE classification an increase of creatinine of 3x or creatinine >4 with acute increase of 0.5 or GFR decrease of more than 75% from baseline would be?
Kidney Failure.
Urine Na of <20mEq/L, fractional excretion of Na(Fena)<1%, urine osmolality of 500 mOsm, and a BUN:Cr >20:1 is what type of kidney injury?
Prerenal injury
Urine Na>40mEq/L, FeNa <1-2%, Urine Osm 250-300, and a BUN of <15:1 is what type of kidney injury?
Intrinsic renal injury
Post renal injury labs would be?
Results vary due to the length of time of obstruction.
Stage 1 kidney damage with normal GFR of above?
>90 mls/min
Stage 2: kidney damage with mild decrease in GFR of ______
60-89 mls/min
Stage 3: moderate decrease of GFR of ______
30-59 mls/min
Stage 4 is a severe decrease of GFR of ________
15-29 mls/min.
Stage 5, kidney failure is GFR less than ______
15 mls/min
BUN/Creat of <15:1 =
BUN/Creat of >20:1 =
<15:1 = intrinsic renal
>20:1 prerenal
What 4 labs would you see in ARF/AKI?
BUN/Creat elevation
Decreased creatinine clearence
Hyperkalemia
Urinalysis (UA) positive for blood and proteins.
What is an irreversible damage to the kidneys, with mild to moderate decrease in GFR over time but no presence of uremic symptoms?
Chronic renal failure.
What are the most common causes of CRF?
HTN and diabetes.
S/S of CRF?
At first asymptomatic, but then progress to fatigue, malaise, vomiting.
What would BUN and Creat be in CRF? What about UA and serum electrolytes?
BUN/Cr elevated
UA and serum electrolytes are generally normal until advanced stages.
What is the primary buffer system of the body?
Carbonic acid and bicarbonate system
CO2 = acid - regulated by the lungs
Bicarb - base - regulated by the kidneys.
Increase in blood CO2 levels =
Decrease in blood CO2 levels =
Increase in blood bicarb levels =
Decrease in blood bicarb levels =
Respiratory acidosis
Respiratory alkalosis
Metabolic alkalosis
Metabolic acidosis.
MUDPILES?
M- methanol
U - Uremia
D - DKA
P - Paraldehyde
I - Iron, Isoniazid
L - Lactic acidosis
E - Ethanol, Ethylene glycol
S - Salicylate/ASA/Aspirin.
What is an anion gap?
Measure of acid-base balance,
AG = (Na+ + K+) - (Cl- + HCO3-)
