The basic metabolic panel Flashcards
What information does the basic metabolic panel(BMP) provide?
- concentration of electrolytes
- volume status
- acid- base status
- Baseline renal function
What does the BMP consist of?
- sodium
- potassiun
- chloride
- bicarbonate
- blood urea nitrogen(BUN)
- creatinine
- glucose
What do electrolytes have effect on?
- hydration
- acid-base balance
- osmotic pressure
- pH
- heart and muscle contraction
What affects sodium levels?
- hydration status (total free water in serum) Na very sensitive to water in body
- glucose concentration
- Hypothalamus regulates water (any disruption can result in dysnatremias)
What affects potassium levels?
- hydration status
- glucose concentration
- beta-agonists
- insulin
What is osmolarity and what is the normal range?
- the concentration of all solutes per liter of solution
- normal range: 280-300mosm/l
What does decreased vs increased osmolarity tell about fluid status?
- Decreased: increase in total body fluids (more dilute)
- Increases: decrease in total body fluid (concentrated)
What electrolytes account most for osmolarity?
- Na (primary determinant)
- glucose
- BUN
What is normal range of Na?
- 135-145 mEq/L
What are signs and symptoms of hyponatremia?
- serum concentration below 135 (s&s occur below 125)
- headache
- n/v
- weakness
- seizure
- coma
What is euvolemic hyponatremia?
- too little sodium in extracellular space
- normal amount of fluid in the cell
What is hypervolemic hyponatremia?
- enough sodium in ecs (body) but too much fluid in the body (over diluted)
What is hyperosmolar hyponatremia?
- enough sodium in ecs (body) but fluid from ics dilutes the ecs, ( the cell shrink)
- High osmolarity due to increase in glucose
How to correct for sodium in hyperosmotic hyponatremia if someone’s glucose is high?
- to get an accurate estimate of sodium, increase the sodium by 1.6 for every 100 mg/dL of glucose over 100 mg/dL.
- example: glucose = 600, thats 500 over normal 100 so 5x1.6 = 8, Na = 128, actual Na = 128+8 = 136
What causes euvolemic hyponatremia?
- low sodium intake
- high sodium excretion
- hypothalamus regulation of water issues
What causes hypervolemic hyponatremia?
- heart failure
- liver failure/cirrhosis
- renal failure
- extra IV fluid administration
What causes hyperosmolar hyponatremia?
- hyperglycemia/diabetic ketoacidosis
What are the treatment for hyponatremia?
- depends on the type
- correct the underlying disorder
- fluid restriction
- replace sodium through hypertonic saline
What are the signs/symptoms of hypernatremia?
- concentration above 145 mEq/L
- altered mental status
- seizures
- hyperreflexia
- spasticity (tight muscles)
- lethargy
What are the causes of hypernatremia?
- volume loss
- hyperaldosteronism
- exogenous administration of Na (hypertonic IV fluid)
What are the treatment for hypernatremia?
- restore fluids with intravenous and/or oral rehydration (regular saline)
what is the normal range of potassium and what can affect it?
- normal range (3.5-5.0mEq/l)
- renal dysfunction (kidney is the main regulator of potassium homeostasis)
- dietary intake
- Meds side effects
What are the signs and symptoms of hypokalemia?
- concentration below 3.5
- muscle weakness
- constipation
- palpitation
- fatigue
- ECG changes (flattened T wave, ST segment depressions, u-waves)
What are the treatment of hypokalemia?
- oral/IV replacement
- replace low magnesium first if hypomagnesemia is present (mg regulates NaKATPase pump)
What causes hyperkalemia?
- concentration above 5
- renal insufficiency/failure
- acidosis
- meds (ACE inhibitor, Angiotensin II receptor blocker, aldosterone antagonist)
In what condition would you get a falsely elevated potassium reading?
- hemolysis of rbc when drawing the blood or shaking the tube, resulting in K to leak out of cell
- always get another lab test done if pt coming from outside clinic
What are the signs and symptoms of hyperkalemia?
- muscle weakness
- muscle cramping
- paresthesias
- ECG changes (peaked T waves, prolonged PR interval, as it progresses it will result in Wide QRS complex)
What are the treatments for hyperkalemia?
- IV calcium (stabilizes cardiac membranes, prevent QRS from widening more)
- insulin (and glucose), promotes shunting of potassium into the intracellular compartment
- beta agonists (causes K to shift inside)
- potassium excretion (oral or rectal), kayexalate
- dialysis
How is chloride levels adjusted?
- absorption through small intestine and stomach
- secretion/reabsorption in the renal tubules
- Normal range 96-106
What can cause hypochloremia?
- concentration <96
- prolonged vomiting (high level of cl in gastric fluid)
- NGT suctioning
- GI acid supression
- results in primary metabolic alkalosis
- could be due to compensation for a respiratory or metabolic acidosis
What can cause hyperchloremia?
- concentration >106
- could be due to aggressive administration of IV fluids
- results in primary metabolic acidosis
- could be due to compensation for an alkalosis
Where is bicarbonate produced and what is the normal range?
- produced and excreted through kidneys
- normal range 22-28
What does high vs low bicarbonate lead to?
- high bicarbonate = alkalosis (buffers acid in the blood, bring pH back to normal)
- low bicarbonate = acidosis
What is the normal range for calcium and what are some of it’s functions?
- 8.5 - 10
- required for blood coagulation, muscle contractions, nerve conduction, osteoclastic activity
- stored in bones and teeth
- regulated by parathyroid, thyroid and kidneys
What are some causes of calcium alterations?
- thyroid disease
- parathyroid disease
- renal failure
- vitamin D deficiency
- cancer if metastasize to bone
What are signs and symptoms of hypocalcemia?
- chvostek sign (facial spasms with percussion of facial nerve)
- trousseau sign (hand contracts inward with inflation of a BP cuff)
- paresthesias (pins and needles)
- muscle cramps/spasms
- hyperreflexia
- tetany
- seizures
- ECG changes (prolonged QT interval, torsades de pointes)
What is the treatment for hypocalcemia?
- oral/IV replacement
- replace mg if needed (mg has an effect on Ca absorption and balance)
What causes hypercalcemia?
- concentration above 10
- hyperparathyroidism
- bone malignancy
- prolonged immobilization
What are the signs and symptoms of hypercalcemia?
- abdominal pain
- bone pain
- muscle weakness
- nephro/ureterolithiasis (kidney stones)
- confusion/lethargy/fatigue
BONES, MOANS, PSYCHIC GROANS, FATIGUE OVERTONES, STONES
What is the treatment for hypercalcemia?
- IV fluid administration (dilute and promotes excretion)
- loop diuretics
- restriction of calcium containing foods
- dialysis
What is function of Mg in cells and what is its normal range?
- Normal range: 1.5 - 2.5
- required for ATP processing, metabolism, neuromuscular transmission
- regulated similar to Ca
What are the causes for hypomagnesemia and what is the treatment?
- poor dietary intake
- decreased intestinal absorption
- increased renal excretion
- GI losses (V/D)
Treatment: Oral/IV replacement
What are the signs and symptoms of hypomagnesemia?
- concentration below 1.5
- lethargy
- confusion
- tremor
- paresthesias
- hyperreflexia
- seizures
What causes hypermagnesemia?
- concentration above 2.5
- renal failure
- antacid overuse
- over-zealous replacement
What are the signs and symptoms of hypermagnesemia?
- decreased DTRs (reflexes)
- bradycardia
- hypotension
- flaccid paralysis
- cardiac arrest
What is the treatment of hypermagnesemia?
- loop diuretics
- restriction of magnesium containing foods or meds
- dialysis
What are the 2 types of nitrogens?
- protein nitrogen
- non-protein nitrogen (urea, creatinine)
What can cause increased concentration of nitrogen compounds?
- decreased renal function (most nitrogen is excreted through kidneys)
What is BUN?
- blood urea nitrogen
- waste product of protein metabolism
- dependent on dietary protein
- excreted by kidneys
- bad kidneys = more urea
What is the normal range of BUN and what does it estimate?
- 7 - 20 (rough estimate of renal function)
- high levels = uremia
- decreased levels not clinically significant
What is creatinine?
- non-protein form of nitrogen that test kidney function
- more muscle, higher creatinine
- excreted only by kidneys
- increase Cr = bad kidney function
- not dependent on dietary protein
- decreased levels not considered clinically significant
- Normal range 0.6 - 1.2
What is the elevation in both BUN and Cr called?
- Azotemia (due to renal insufficiency)
What are the 3 renal azotemia?
- prerenal azotemia: results from poor perfusion of the
kidney, dehydration, shock, diminished blood volume - renal azotemia: results from disease of kidney itself (glomerulonephritis, pyelonephritis(infection of kidney), polycystic kidney disease, nephrosclerosis
- post renal azotemia: results from obstruction of excretion (kidney stones, enlarged prostate, prostate tumors, bladder tumor)
What is the relationship between BUN and Cr?
Normal ratio = 10:1 - 20:1
- > 20:1 suggests prerenal causes (dehydration)
- <10:1 suggests renal causes (ATN, glomerulonephritis, CKD)
