The Complete Metabolic Panel (CMP) Flashcards
What are common indications of the CMP?
- measurement of kidney function
- measurement of liver function
- measurement of electrolytes
- Using the CMP for monitoring kidney function is important in those with (…)
- CMP is used commonly in management of what conditions?
- CMP is used in suspected acute kidney injury from what?
- chronic diseases that can harm kidney function
- diabetes, hypertension, kidney disease
- dehydration, medications
Using the CMP is important for monitoring the health of the liver in what conditions?
- alcohol abuse disorder
- viral hepatitis
- cirrhosis of liver
- medication side effects
- The CMP is used for measurement of electrolytes, especially (1) and (2)
- CMP can be helpful to evaluate what?
- sodium and potassium
- blood protein levels, such as albumin (is the kidney spilling albumin into the urine)
What are the different monitoring parameters of the CMP?
- electrolyte function and abnormalities (sodium, potassium, chloride, CO2, anion gap, calcium)
- renal function (BUN and creatinine)
- liver function (bilirubin, alkaline phosphatase, AST, ALT)
- proteins (albumin, total protein)
- glucose monitoring (Diabetes)
What are frequent reasons to order a CMP?
- evaluation of abdominal pain to check for elevated liver enzymes, renal dysfunction
- evaluate for abnormalities of glucose levels in diabetes
- evaluate potassium/renal function in treatment of hypertension
- evaluate for liver dysfunction/liver toxicities with medication
- part of complete wellness physical
- What is the normal range of sodium?
- What is the normal range of potassium?
- What is the normal range of glucose?
- What is the normal range of BUN?
- What is the normal range of creatinine?
- 135-145 mEg/L
- 3.5-5.0 mEg/L
- 70-110 mg/dL
- 8-23 m mg/dL
- 0.7-1.3 mg/dL (males); 0.6-1.1 mg/dL (females)
- What is predominant in intracellular fluid?
- What is predominant in extracellular fluid (intravascular + interstitial)?
- potassium
- sodium
What is the predominant cation in the ECF and is a major determinant of ECF osmolality?
Na (sodium)
ECF osmolality (concentration of solutes) is the major determinant that controls (…)
sodium regulation
What are drivers of sodium homeostasis?
- free water and sodium excretion by the kidneys (most important)
- dietary sodium intake
What is the process of sodium regulation?
- receptors in the carotids, kidneys, or hypothalamus sense changes in sodium tonicity
- action is triggered
- When sodium levels are low, what happens?
- When sodium levels are high, what happens?
- aldosterone decreases sodium loss in the kidneys
- natriuretic hormone (the “sodium diuretic”) increases sodium loss in the kidneys
- What is also important in sodium regulation that is also known as vasopressin?
- Where is this produced and released by?
- What does this control?
- antidiuretic hormone (ADH)
- produced in hypothalamus and released by pituitary
- controls water “levels” that affect sodium level by dilution
When ADH is secreted, what happens?
- there is an increase in renal free water reabsorption
(as more water is reabsorbed, sodium is diluted and sodium concentration decreases)
What is the sodium regulation by ADH when plasma water inceases?
- plasma water increases
- sodium and osmolality decreases (by dilution)
- ADH secretion decreases
- collecting renal tubule becomes impermeable to water so water is not reabsorbed which increases need for urination
Decreasing ADH increases what?
urination (diuresis)
What is the sodium regulation by ADH when plasma water decreases?
- plasma water decreases
- sodium and osmolality increase
- ADH secretion increases
- collecting renal tubules reabsorbs more water, decreasing urination
Increasing ADH decreases what?
- diuresis (anti-diuretic hormone)
What are causes of hyponatremia (low sodium)?
- GI losses
- renal disease
- medications
- dietary sodium intake
- In hyponatremia, what is included in GI losses?
- What are you losing?
- How can this be corrected?
- vomiting, diarrhea
- losing sodium and fluids
- IV hydration (0.9% normal saline fluids)
- In hyponatremia, renal disease can lead to alterations in mechanisms for what?
- This results in what?
- water and sodium homeostasis
- impairment of free water excretion in kidneys, so water is retained, resulting in dilution of sodium
What medications usually cause hyponatremia?
mediations that treat hypertension
- thiazide diuretics named hydrochlorothiazide and Chlorthalidone
What is probably one of the most common reasons hyponatremia is seen?
medication use (hypertension meds)
In most cases, hyponatremia would only be seen in (…) dietary changes of reduced sodium
extreme dietary changes
Hypernatremia can result from what?
- increased sodium intake
- increased water loss in some cases but body releases ADH and thirst in response
- Usually, hypernatremia occurs in (…) water loss
- Which individuals do you see this in?
- unreplaced water loss
- elderly pts (if impaired mental faculties; may have diminished thirst stimulation; unable to access water after a fall)
- pts not given free access to water
- hypertonic saline solutions
- salt tablet ingestion
What diseases cause excessive water diuresis, concentrating the sodium, resulting in hypernatremia?
- diabetes insipidus (impaired ADH secretion = more dilute, watery urine)
What is the major intracellular cation? What percentage is intracellular?
- potassium
- 98%
Dietary intake of potassium should be relatively equal with (…)
potassium excretion
- What excretes 90-95% of potassium?
- What excretes the remaining 5-10%?
- kidneys
- colon
- What is the intracellular concentration of potassium?
- What is the value for plasma potassium concentraion?
- 150 mEq/L
- 4 mEq/L
Large amounts of potassium is intracellular, the (1) especially, but also cells of the (2), (3), and (4)
- myocytes
- liver
- bone
- erythrocytes
- If you eat a heavy potassium load, your body works to move most of that potassium into the (…)
- Even if 1% of intracellular potassium is shuffled to plasma, it can cause (…)
- cells
- dynamic increase in serum potassium to dangerous levels
Both hypokalemia and hyperkalemia can cause (…) due to its effects on (…)
- cardiac arrest
- cardiac muscle contractility
Simply moving your forearm during venipuncture can cause release of (1) and (2) results (false reading)
- potassium
- increase
What can lead to hypokalemia?
- diuretics used in hypertension (hydrochlorothiazide and chlorthalidone)
- decreased dietary intake of potassium
- diarrhea that results in loss of potassium
What can lead to hyperkalemia?
- ACE inhibitors used in hypertension (the “prils”)
- increased dietary intake of potassium
- crush injuries in which potassium is spilled from intracellular compartments into plasma
- What is one of the more important values on a CMP used to identify individuals at risk of diabetes or affected by diabetes?
- How can you check this value?
- glucose level
- capillary blood or whole blood
Glucose levels are a direct result of feedback mechanisms and are controlled by (1) and (2)
- glucagon
- insulin
(…) levels rise after eating, then cells in the Islet of Langerhans in the pancreas secrete (…) to decrease those levels
- glucose
- insulin
What leads to hypoglycemia?
- insulin or oral anti-diabetic medication overdose
- starvation
- insulin-secreting tumors (insulinoma)
What leads to hyperglycemia?
- diabetes
- stress
- pancreatitis
- oral corticosteroids (such as prednisone)
What is the function of the kidney?
maintain homeostatic balance of fluids, acid/bases, and electrolytes, conserve metabolic products, excrete wastes and produce hormones
What is the main filtering structure of the kidney?
the glomerulus
What is the number of milliliters of body fluid cleared by the kidneys per unit of time (mL/min)?
glomerular filtration rate
- Formation of what occurs primarily in the liver due to catabolism of protein into amino acids?
- What is formed in this process?
- What then combine to form urea?
- What is urea filtered by?
- urea
- ammonia
- ammonia molecules combine
- glomerulus
Approximately how much of urea is reabsorbed in renal tubules and the rest is excreted in urine?
50%
What does BUN (blood urea nitrogen) reflect?
the metabolic functioning of the liver and the excretory function of the kidneys
What leads to increased BUN?
- high protein diets
- GI bleeding
- dehydration
- renal failure
What leads to decreased BUN?
- low protein diets or starvation
- liver failure
- overhydration
- What is a very common cause of an increased BUN?
- What is a very common cause of a decreased BUN?
- dehydration
- overhydration
Any condition that results in low blood flow (volume) leads to increased reabsorption of BUN in the proximal convoluted tubule of the kidney, leading to (…)
increased BUN levels
Increased fluids and higher flow through the glomerulus results in decreases reabsorption of BUN, leading to (…)
decreased BUN levels
If a pt looks healthy and eats normal but has a low BUN, what is probably happening?
pt is probably drinking a lot of water
What values are renal function studies?
BUN and creatinine