Download Commonly ordered laboratory test

Commonly ordered laboratory
tests
What it is?
Common Interpretations
Nursing Implications
&
Specimen collection
(there is some variation from hospital to hospital on the color Vacutainer tube)
CBC
• The CBC may be performed under many different conditions and in the
assessment of many different diseases. It is a screening test used to
diagnose and manage numerous diseases. The results can reflect
problems with fluid volume (such as dehydration) or loss of blood. The
test can reveal problems with red blood cell production and destruction,
or help diagnose infection, allergies, and problems with blood clotting.
• Complete Blood count
– WBC
• The differential
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RBC
HGB
HCT
MCV
MCH
Plt
• Purple Vacationer
WBC
• The white blood cell (WBC) count is a count of the
number of white blood cells per volume of blood. Both
increases and decreases can be significant. Depending
on the laboratory's report forms, white blood cells are
reported as thousands in a microliter of blood (for
example 5,000/µL or 5.0x103/µL) or as millions in a
liter of blood (5.0x109/L).
• The white blood cell differential looks at the types of
white blood cells present. There are five different types
of white blood cells, each with its own function in
providing protection from infection. The differential
classifies a person's white blood cells into each type:
neutrophils (also known as segs, PMNs, grans),
lymphocytes, monocytes, eosinophils, and basophils.
• WBC may be increased with infections,
inflammation, cancer, & leukemia
• WBC may be decreased with some
medications, some autoimmune conditions,
some severe infections, bone marrow failure,
and congenital marrow aplasia
The diff
• Neutrophil granulocytes
– May indicate bacterial infection. May also be raised in acute viral infections.
Because of the segmented appearance of the nucleus, neutrophils are
sometimes referred to as "segs."
• Lymphocytes
– Higher with some viral infections also raised in lymphocytic leukaemia CLL.
Can be decreased by HIV infection. In adults, lymphocytes are the second
most common WBC type after neutrophils.
• Monocytes
– May be raised in bacterial infection, tuberculosis, malaria, Rocky Mountain
spotted fever, monocytic leukemia, chronic ulcerative colitis and regional
enteritis
• Eosinophil granulocytes
– Increased in parasitic infections, asthma, or allergic reaction.
• Basophil granulocytes
– May be increased in bone marrow related conditions such as leukemia or
lymphoma
• What in the heck is a “shift”?
– "shift to the left" means that the bands or stabs have increased, indicating an
infection in progress.
RBC
• The red blood cell (RBC) count is a count of the number
of red blood cells per volume of blood. Both increases
and decreases can point to abnormal conditions.
Depending on the laboratory's report forms, red blood
cells are reported as millions in a microliter of blood
(4,250,000/µL or 4.25x106/µL) or as millions in a liter
of blood (4.25x1012/L).
• RBC’s constitute the majority of peripheral blood cells.
They are formed by the bone marrow, have a lifespan
of 120 days, and are removed from the blood by the
liver spleen, and bone marrow. RBC function in Hgb
transport, which results in delivery of oxygen to the
body tissues.
Hemoglobin & Hematocrit
• Hemaoglobin- Hgb
– measures the amount of
oxygen-carrying protein
in the blood
• Hematocrit- Hct
– measures the amount of
space red blood cells
taken up in the blood. It
is reported as a
percentage.
Hemaglobin abnormalities
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Elevated Hgb
– congenital heart disease
– cor pulmonale
– pulmonary fibrosis
– polycythemia vera
– increased RBC formation associated with excess erythropoietin
– Erythropoietin use
Decreased Hgb
– Hemorrhage
– Anemia
– erythropoietin deficiency (from kidney disease)
– red blood cell destruction associated with transfusion reaction
– lead poisoning
– malnutrition
– nutritional deficiencies of iron, folate, vitamin B-12, vitamin B-6
– over hydration
Hematocrit Abnormalities
• Elevated Hct
– people living at high altitude
– chronic smokers
– Dehydration produces a falsely high hematocrit that disappears
when proper fluid balance is restored.
– lung disease, certain tumors, a disorder of the bone marrow
known as polycythemia rubra vera
– abuse of the drug erythropoietin
• Decreased Hct
– anemia
• loss of blood, i.e. traumatic injury, surgery, bleeding colon
cancer
• nutritional deficiency ; iron, vitamin B12, folate
• bone marrow problems
MCV & MCH
Mean corpuscular volume & Mean corpuscular hemoglobin
• The MCV reflects the size of red blood cells.
• The MCH is a calculation of the amount of oxygen-carrying
hemoglobin inside RBC.
• These RBC measures are used to diagnose types of anemia.
– MCV less than lower limit of normal: microcytic anemia
– MCV within normal range: normocytic anemia
– MCV greater than upper limit of normal: macrocytic
anemia
– MCH less than lower limit of normal: hypochromic anemia
– MCH within normal range: normochromic anemia
– MCH greater than upper limit of normal: hyperchromic
anemia
Platlets
• Plt, or thrombocytes
– are small cytoplasmic bodies derived from cells. They
circulate in the blood and are involved in hemostasis
leading to the formation of blood clots.
• Increased Plt- thrombocytosis
– Thrombosis formation
• Decreased Plt- thrombocytopenia
– excessive bleeding
Remember this????
BMP
Basic Metabolic Panel
aka Astra 8 & Chem 7
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The BMP is often ordered in the hospital because its components give doctors
important information about the current status of your kidneys, electrolyte and
acid/base balance, blood sugar, and calcium levels. Significant changes in these
test results can indicate acute problems, such as kidney failure, insulin shock or
diabetic coma, respiratory distress, or heart rhythm changes.
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BMP
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Glucose
Calciulm
Sodium
Potassium
Carbon Dioxide
Chloride
BUN
Creatinine
Green Vacutainer
Calcium
• Calcium
– one of the most important minerals in your body. It is essential for the
proper functioning of muscles, nerves, and the heart and is required in
blood clotting and in formation of bones. About 99% of calcium is
found in the bones while the remainder circulates in the blood.
Roughly half of the calcium in the blood is “free” and is metabolically
active. The remaining half is “bound” calcium. It is attached to albumin
and other compounds and is metabolically inactive.
Common causes of Hypercalcemia
• Hyperparathyroidism
• Cancer. Cancer can cause hypercalcemia when it spreads to the bones,
which releases calcium into the blood, or when a cancer produces a hormone
similar to PTH, resulting in increased calcium levels.
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Hyperthyroidism
Tuberculosis
Prolonged immobilization
Excess Vitamin D intake
Kidney transplant
Signs/Symptoms & Complications of
hypercalcemia
• "Bones, stones, groans, and psychiatric overtones" is a
saying which will help you remember the signs and
symptoms of hypercalcemia.
• Hypercalcemia can result in fatigue, depression,
confusion, anorexia, nausea, vomiting, constipation,
pancreatitis or increased urination.
• Chronic hypercalcemia can result in urinary calculi
• Abnormal heart rhythms
• Severe hypercalcemia is considered a medical
emergency, coma and cardiac arrest can result.
Causes of Hypocalcemia
• Low blood protein levels, especially a low level of albumin.
• Hypoparathyroidism, Inherited resistance to the effects of
parathyroid hormone
• Extreme deficiency in dietary calcium
• Decreased levels of vitamin D
• Magnesium deficiency
• Increased levels of phosphorus
• Acute inflammation of the pancreas (pancreatitis)
• Renal failure
• Malnutrition
• Alcoholism
Signs/Sypmtoms & Complications of
hypocalcemia
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Seizures (all types)
Dementia (in adults)
mental retardation (in children)
Emotional problems (anxiety, depression)
Extrapyramidal symptoms (parkinsonism is most common)
Papilledema
Increased Neuromuscular Irritability
Chvostek's sign
Trousseau's sign
Paresthesias in fingers & toes
Muscle stiffness
Prolongation of QT interval
Congestive heart failure
Hypotension
Biliary colic
Bronchospasm
Diaphoresis
Cataracts, Dry coarse skin, dermatitis, hyperpigmentation, and eczema
Nursing Implicatons R/T
calcium imbalences
• Hypercalcemia
– Hospitalized patients may require IV fluids,
diuretics, hemodialysis, glucocorticoids treatment
– Telemetry monitoring
• Hypocalcemia
– Hospitalized patients may require IV calcium
replacement
– Education about calcium & vitamin D
supplements, dietary sources of calcium
Sodium
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Sodium (Na) is a mineral that is vital to normal body processes, which include
nerve and muscle functioning.
Na is a positively charged molecule that works with other electrolytes, such as
potassium, chloride, and bicarbonate (or total CO2), to help your cells function
normally and help regulate the amount of fluid in the body.
Na is present in all body fluids but is found in the highest concentration in the
blood and in the fluid outside of the body’s cells. This extracellular Na, as well
as all body water, is regulated by the kidney.
The body uses what Na it requires and the kidneys excrete the rest in the urine
to maintain Na concentration within a very narrow range. It does this by
producing hormones that can increase or decrease sodium losses in urine,
producing a hormone that prevents water losses , and controlling thirst.
When the level of sodium in the blood changes, the water content in your
body also changes. These changes can be associated with dehydration or
edema, especially in the legs.
Hypernatremia
• Hypernatremia is generally not caused by an
excess of sodium, but rather by a relative
deficit of free water in the body.
• Dehydration without enough water intake.
• Increased salt intake without enough water
• Cushing Syndrome
• Diabetes insipidus
Signs/Symptoms & Complications of
hypernatremia
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Lethargy
Weakness
Irritability
Edema
Dry mucous membranes
Thirst
Restlessness
Seizures
Coma
Hyponatremia
• Hyponatremia is rarely due to decreased sodium
intake (deficient dietary intake or deficient
sodium in IV fluids).
• Most commonly, it is due to sodium loss
– Addison’s disease, diarrhea, excessive sweating,
diuretic administration, or kidney disease.
• In some cases, hyponatremia is due to increased
water
– drinking too much water, heart failure, cirrhosis, &
kidney diseases that cause protein loss.
Signs/Symptoms & Complications of
hyponatremia
• Severe or rapidly progressing hyponatremia
can result in cerebral edema, caused by an
osmotic shift of water from the plasma into
the brain cells.
• Symptoms include
– nausea, vomiting, headache and malaise
– confusion, diminished reflexes, convulsions,
stupor or coma
Nursing interventions R/T sodium
imbalances
• Hypernatremia
– administration of free water to correct the relative
water deficit. Water can be replaced orally or intravenously.
However, overly rapid correction of hypernatremia is potentially very
dangerous. Rapidly lowering the sodium concentration with free
water, causes water to flow into brain cells and causes them to swell.
This can lead to cerebral edema, potentially resulting in seizures,
permanent brain damage, or death.
• Hyponatremia
– Because of the complex nature and etiologies of
hyponatremia, medical treatment is highly variable
Potassium
• Potassium is an electrolyte
• A positively charged molecule that works with other electrolytes, such as
Na, Cl, and HCO3 to help regulate the amount of fluid in the body,
stimulate muscle contraction, and maintain a stable acid-base balance.
• Potassium is present in all body fluids, but most potassium is found within
your cells. Only about two percent is present in fluids outside the cells and
in the liquid part of the blood (called serum or plasma).
• Because the blood concentration of potassium is so small, minor changes
can have significant consequences. If potassium levels go too low or too
high, your health may be in considerable danger: you are at risk for
developing shock, respiratory failure, or heart rhythm disturbances. An
abnormal concentration can alter the function of neuromuscular tissue;
for example, the heart muscle may lose its ability to contract.
Common causes of Hyperkalemia
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Acute or chronic kidney failure
Addison’s Disease
Hypoaldosteronism
Injury to tissue
Infection
Diabetes
Dehydration
Excessive dietary potassium intake (for example, fruits are particularly
high in potassium, so excessive intake of fruits or juices may contribute to
high potassium)
• Excessive intravenous potassium intake
• Certain drugs can also cause hyperkalemia in a small percent of patients.
Among them are non-steroidal anti-inflammatory drugs ; beta blockers,
angiotensin-converting enzyme inhibitors , and potassium-sparing
diuretics .
Signs & Symptoms of hyperkalemia
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Malaise
Palpitations
Muscle weakness
EKG changes
– reduction of the size of the P wave and
development of peaked T waves
– widening of the QRS complex, and the EKG
complex can evolve to a sinusoidal shape
Why Hyperkalemia is bad…
• Hyperkalemia is considered a medical
emergency due to the risk of potentially fatal
arrhythmia's.
• The primary cause of morbidity and death in
hyperkalemia is potassium's effect on cardiac
function.
• The mortality rate can be as high as 67% if
severe hyperkalemia is not treated rapidly.
Common causes of Hypokalemia
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Dehydration
Vomiting
Diarrhea
Hyperaldosteronism
DKA
Deficient potassium intake (rare)
Complications of acetaminophen overdose
Certain drugs such as corticosteroids, beta-adrenergic
agonists, alpha-adrenergic antagonists, some
antibiotics , and the antifungal agent amphotericin B
can cause loss of potassium.
Signs/Symptoms & Complications of
hypokalemia
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Mild hypokalemia
– elevation of blood pressure
– cardiac arrhythmias
Moderate hypokalemia
– muscular weakness, myalgia, and muscle cramps
– constipation
Severe hypokalemia
– flaccid paralysis
– hyporeflexia, and tetany
– rhabdomyolysis occurring with profound hypokalemia with serum potassium levels less
than 2 mEq/L.
– Respiratory depression from severe impairment of skeletal muscle function is not
uncommon.
EKG changes
– flattened T waves
– ST segment depression
– prolongation of the QT interval. The prolonged QT interval may lead to arrhythmias.
Nursing interventions R/T
hyperkalemia
• Hyperkalemia
– Emergency lowering of potassium levels is mandated when
K level >6 mmol/l. The physician may order a cocktail of
medications which may include: Calcium, Insulin,
Bicarbonate, Dextrose, Kayexalate and Ventolin
– Refractory or severe cases may need dialysis to remove the
potassium from the circulation.
– Telemetry & serial serum potassium monitoring
– Education on the prevention of
hyperkalemia typically involves
reduction of dietary potassium,
removal of an offending medication,
and/or the addition of a diuretic.
Nursing Interventions R/T hypokalemia
• Treatment in severe hypokalemia is addressing
the cause, such as improving the diet, treating
diarrhea or stopping an offending medication.
• Mild hypokalemia may be treated with oral
potassium chloride supplements .
• Educate patient on potassium-containing foods
such as leafy green vegetables, tomatoes, citrus
fruits, oranges or bananas.
• Severe hypokalemia may require intravenous
replacement.
Aren’t we done with the BMP yet??
Nope not even close!
Carbon dioxide
• The total CO2 test measures the total amount of
carbon dioxide in the blood, mostly in the form of
bicarbonate , HCO3. Bicarbonate is a negatively
charged electrolyte that is excreted and reabsorbed by
the kidneys. It is used by the body to help maintain the
body’s acid-base balance and secondarily to work with
sodium, potassium, and chloride to maintain electrical
neutrality at the cellular level.
• Measuring bicarbonate (or total CO2) as part of a
metabolic panel may help diagnose an electrolyte
imbalance, acidosis or alkalosis as the result of a
disease process or condition.
Common causes of both elevated &
decreases CO2/HCO3
• Increased CO2
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Severe vomiting , dehydration
Lung diseases
Cushing’s syndrome
Conn’s syndrome
Metabolic alkalosis
• Decreased CO2
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Addison’s disease
Chronic diarrhea, malnutrion
Diabetic ketoacidosis
Metabolic acidosis
Kidney disease
Ethylene glycol or methanol poisoning
Salicylate (aspirin) overdose
Burns
Shock
Sign/Symptoms & Complications of
decreased CO2
• Decreased CO2/HCO3 is considered to be metabolic
acidosis, which S/S include:
– chest pain, palpitations
– headache, altered mental status, decreased visual acuity
– nausea, vomiting, abdominal pain, altered appetite (either loss
of or increased) and weight loss
– muscle weakness and bone pains.
– Kussmaul respirations (classically associated with diabetic
ketoacidosis). Rapid deep breaths increase the amount of
carbon dioxide exhaled, thus lowering the serum carbon dioxide
levels
– lethargy, stupor, coma, seizures
– arrhythmias
– hypotension
• Keep in mind the abovementioned S/S will occur mostly in
profound acidosis along with other metabolic disturbances
Signs/Symptoms & Complications of elevated
CO2/HCO3
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ElevatedCO2/HCO3 is considered to be metabolic alkolosis, which S/S include:
– hypokalemia is usually present
– weakness, myalgia, and polyuria
– Hypoventilation develops because of inhibition of the respiratory center in the medulla.
– Symptoms of hypocalcemia, including jitteriness, perioral tingling, muscle spasms, tetany, Chvostek
sign, Trousseau sign
– Vomiting or diarrhea - GI losses of HCl , think bulimia…
– Drug use
• Loop or thiazide diuretics
• Licorice
• Tobacco chewing
• Carbenoxolone
• Fludrocortisone
• Glucocorticoids
• Antacids (eg, magnesium hydroxide)
• Calcium carbonate
– change in mental status, or seizures
– evaluation of hypertension and volume status. Hypertension accompanies several causes of
metabolic alkalosis. Volume status assessment includes evaluation of orthostatic changes in blood
pressure and heart rate, mucous membranes, presence or absence of edema, skin turgor, weight
change, and urine output.
Nursing implications
• Correction of metabolic alkalosis (increase of CO2/HCO3) depends
primarily on the underlying etiology .
– In the case of vomiting, administer antiemetics, if possible.
– If continuous gastric suction is necessary, gastric acid secretion can be
reduced with H2-blockers or more efficiently with proton-pump
inhibitors.
– Medications to dec
• Correction of metabolic acidosis (decreased CO2/HCO3 levels) may
include:
– IV bicarbonate replacement
– Hemodialysis, usually used if a toxic poisoning or overdose has caused
the acidosis.
• DO NOT CONFUSE THE CO2 OF THE BMP WITH PCO2 OF ANF ABG,
they are not the same!!!!
Chloride
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Chloride is an electrolyte, a negatively charged molecule that works with other
electrolytes, such as potassium, sodium, and bicarbonate (sometimes measured as
total carbon dioxide [CO2]), to help regulate the amount of fluid in the body and
maintain the acid-base balance.
Chloride is present in all body fluids but is found in the highest concentration in
the blood and in the fluid outside of the body’s cells.
When there is an acid-base imbalance, however, blood chloride levels can change
independently of sodium levels as chloride acts as a buffer. It helps to maintain
electrical neutrality at the cellular level by moving into or out of the cells as
needed.
Chloride is taken into the body through food and table salt, which is made up of
sodium and chloride molecules.
Most of the chloride is absorbed by the gastrointestinal tract, and the excess is
excreted in urine. The normal blood level remains steady, with a slight drop after
meals (because the stomach produces acid after eating, using chloride from
blood).
Chloride levels increase and decrease proportionately with sodium and inversely
with bicarbonate
Causes of chloride imbalances
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Hyperchloremia
– Dehydration
– Cushing's syndrome
– Kidney disease
– Metabolic Acidosis
– Respiratory Alkalosis
– Diarrhea
– over activity of the parathyroid glands
– Polypharmacy (diuretics, carbonic anhydrase inhibitors, & hormone treatments are
known contributors to hyperchloremia)
Hypochloremia
– occur with any disorder that causes low blood sodium
– prolonged vomiting or gastric suction,
– emphysema or other chronic lung diseases (causing respiratory acidosis)
– metabolic alkalosis
– Drugs such as: bicarbonate, corticosteroids, diuretics, and laxatives
– prolonged diarrhea, sweating or high fevers
Signs/symptoms & treatments of
hyperchloremia
• S/S:
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excess fluid loss such as vomiting and diarrhea
Kussmaul's breathing
Weakness
intense thirst
• Treatments:
– As with most types of electrolyte imbalance, the treatment of high blood
chloride levels is based on correcting the underlying cause.
– If the patient is dehydrated, therapy consists of establishing and maintaining
adequate hydration.
– If the condition is caused or exacerbated by medications or treatments, these
may be altered or discontinued, compile an accurate list of all medications the
patient is taking for MD review.
– If there is underlying kidney disease anticipate a nephrology referral
– If there is an underlying dysfunction of the endocrine or hormone system,
anticipate an endocrinologist referral.
Signs/Symptoms & treatment of
hypochloremia
• S/S:
– Hypochloremia rarely occurs in the absence of other
abnormalities.
– Many people do not notice any symptoms, unless they are
experiencing very high or very low levels of chloride in
their blood.
– Dehydration, fluid loss, or high levels of blood sodium may
be observed
• Treatment:
– Fluid & electrolyte replacement
– Treat the underlying cause
FINALLY!!!
BUN & Creatinine
• BUN- Blood Urea Nitrogen
– measures the amount of urea nitrogen, a waste product of protein
metabolism, in the blood. Urea is formed by the liver and carried by the blood
to the kidneys for excretion. Because urea is cleared from the bloodstream by
the kidneys, a test measuring how much urea nitrogen remains in the blood
can be used as a test of renal function.
• Creatinine
– Measuring serum creatinine is a useful and inexpensive method of
evaluating renal dysfunction. Creatinine is a non-protein waste
product of creatine phosphate metabolism by skeletal muscle tissue.
Creatinine production is continuous and is proportional to muscle
mass.
– Creatinine is freely filtered and therefore the serum creatinine level
depends on the Glomerular Filtration Rate (GFR). Renal dysfunction
diminishes the ability to filter creatinine and the serum creatinine
rises. If the serum creatinine level doubles, the GFR is considered to
have been halved. A threefold increase is considered to reflect a 75%
loss of kidney function.
Increased BUN
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An increase in the BUN level is known as azotemia. An elevated BUN may be
caused by:
– Impaired renal function
– Congestive heart failure as a result of poor renal perfusion
– Dehydration
– Shock
– Hemorrhage into the gastrointestinal tract
– Acute myocardial infarction
– Stress
– Excessive protein intake or protein catabolism
Diseased or damaged kidneys cause an elevated BUN because the kidneys are less
able to clear urea from the bloodstream. In conditions in which renal perfusion is
decreased, such as hypovolemic shock or congestive heart failure, BUN levels rise.
A patient who is severely dehydrated may also have a high BUN due to the lack of
fluid volume to excrete waste products. Because urea is an end product of protein
metabolism, a diet high in protein, such as high-protein tube feeding, may also
cause the BUN to increase. Extensive bleeding into the gastrointestinal (GI) tract
will also cause an elevated BUN because digested blood is a source of urea. For
example, a hemorrhage of one liter of blood into the GI tract may elevate the BUN
up to 40mg/ml.
Decreased BUN
• A decreased BUN may be seen in:
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Liver failure
Malnutrition
Anabolic steroid use
Overhydration, Which can result from prolonged intravenous fluids
Pregnancy (due to increased plasma volume)
Impaired nutrient absorption
Syndrome of inappropriate anti-diuretic secretion (SIADH)
• Because urea is synthesized by the liver, severe liver failure causes a
reduction of urea in the blood. Just as dehydration may cause an
elevated BUN, overhydration causes a decreased BUN. When a
person has "syndrome of inappropriate anti-diuretic secretion"
(SIADH), the anti-diuretic hormone responsible for stimulating the
kidney to conserve water causes excess water to be retained in the
bloodstream rather than being excreted into the urine. SIADH can
cause the BUN level, along with other important substances, to
decrease because the fluid volume of the bloodstream may
significantly increase.
Signs/Symptoms & Complications of
abnormal BUN
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Increased BUN
– oliguria or anuria
– Fatigue
– Confusion
– Pale skin color
– Tachycardia
– Dry mouth (xerostomia)
– edema, anasarca
– Positive orthostatic blood pressure changes
– Uremic frost a condition when urea is secreted through the skin in sweat, which
evaporates away to leave solid uric compounds, resembling a frost
• Decreased BUN
– Jaundice
– Wasting syndrome
Abnormal Creatinine levels
• Increased Creatinine
– damage to a large number of nephrons.
– Impaired renal function
– Chronic nephritis
– Urinary tract obstruction
– Muscle diseases such as gigantism, acromegaly, and
myasthenia gravis
– Congestive heart failure
– Shock
• Decreased Creatinine
– Elderly persons with small stature, decreased muscle mass,
or inadequate dietary protein
– Muscle atrophy can also result in decreased serum
creatinine level
BUN to Creatinine Ratio
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Serum creatinine and BUN are often compared to evaluate renal function. While
serum creatinine increases only with nephron damage, the BUN is affected by
hydration, hepatic metabolism of protein and reduced GFR. The mean ratio of
serum creatinine to the BUN should be approximately 1:10.
High BUN-to-creatinine ratio
– Acute kidney failure, which may be caused by shock or severe dehydration
– A blockage in the urinary tract
– bleeding in the digestive tract or respiratory tract
Low BUN-to-creatinine ratio
– diet low in protein
– severe muscle injury called rhabdomyolysis
– Pregnancy
– Cirrhosis
– syndrome of inappropriate antidiuretic hormone secretion (SAIDH)
Signs/Symptoms of elevated creatinine
level
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anemia
Fatigue, weakness
headache, confusion, seizures
nausea, vomiting, and anorexia
thirst
muscle cramps, muscle twitching
nocturia
Extremity paraestesia
diarrhea
itchy skin, itchy eyes
Pallor - grayish complexion, sometimes yellowish-brownish tone
edema
difficulty breathing
high blood pressure
decreased urine output
gastroparesis
Easiest slide ever…
• Low concentrations of creatinine in serum
have no profound clinical significance
Nursing Implications R/T abnormal
BUN & Creatinine
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Strict I&O’s
Fluid restriction if indicated
Daily weight’s
Monitor Daily Lab values
Telemetry monitoring if indicated
I am so over the BMP!!!!
BNP
• Beta-Natriuretic Peptide
– B-type natriuretic peptide is a cardiac neurohormone
specifically secreted from the ventricles in response to
volume expansion and pressure overload. Levels of Btype natriuretic peptide have been shown to be
elevated in patients with left ventricular dysfunction.
– B-type natriuretic peptide may useful in establishing
or excluding the diagnosis of congestive heart failure
in patients with acute dyspnea.
• CHF vs COPD
• Purple Vacutainer
Elevated BNP
• Serum levels of BNP lower than 100 pg/mL are unlikely
to be from CHF
• Levels of 100-500 pg/mL may be CHF. However, other
conditions that also elevate right filling pressures
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pulmonary embolus,
primary pulmonary hypertension,
chronic renal failure,
cirrhosis
hormone replacement therapy
• BNP levels more than 500 pg/mL are most consistent
with CHF.
Signs/Symptoms & Nursing
Implications of elevated BNP
• Think CHF
– Sob
– Edema
– HTN
– Orthopnea
– Etc, etc
LFT
• Drawn on a green Vacutainer
• Liver Function Test
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Alanine transaminase- ALT
Aspartate transaminase- AST
Alkaline phosphatase- ALP
Total bilirubin- TBIL
Direct bilirubin
Total Protein
Albumin
Globulins
I love my liver
• Alanine transaminase (ALT)
– is an enzyme present in hepatocytes. When a cell is
damaged, it leaks this enzyme into the blood, where it is
measured. ALT rises dramatically in acute liver damage,
such as viral hepatitis or acetaminophen overdose.
• Aspartate transaminase (AST)
– enzyme associated with liver parenchymal cells. It is raised
in acute liver damage, but is also present in red blood cells,
and cardiac and skeletal muscle and is therefore not
specific to the liver. The ratio of AST to ALT is sometimes
useful in differentiating between causes of liver damage.
• Alkaline phosphatase(ALP)
– is an enzyme in the cells lining the biliary ducts of the liver.
ALP levels in plasma will rise with large bile duct
obstruction, intrahepatic cholestasis or infiltrative diseases
of the liver.
Elevation of the A’s…
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Viral hepatitis
Excessive alcohol intake/Alcoholic liver disease
Liver inflammation from medications and certain herbs,
Auto-immune hepatitis - a condition where a person's
immune system mistakes the liver for an invader and
attacks it,
Fatty liver- fat build -up in liver cells, called steatohepatitis
when the fatty liver is inflamed
Inherited liver diseases
Liver tumors
Heart failure
Bilirubin
(not to be confused with weird cousin Billy)
• Total bilirubin (TBIL)
– Bilirubin is a breakdown product of heme. The liver is responsible for clearing
the blood of bilirubin. It does this by the following mechanism: bilirubin is
taken up into hepatocytes, conjugated, and secreted into the bile, which is
excreted into the intestine.
• Increased total bilirubin causes jaundice, and can signal a number of
problems:
– Prehepatic: Increased bilirubin production. This can be due to a number of
causes, including hemolytic anemias and internal hemorrhage.
– Hepatic: Problems with the liver, which are reflected as deficiencies in
bilirubin metabolism Some examples would be cirrhosis and viral hepatitis.
– Posthepatic: Obstruction of the bile ducts, reflected as deficiencies in bilirubin
excretion. Obstruction can be located either within the liver or in the bile duct
• Direct bilirubin
– If direct (i.e. conjugated) bilirubin is normal, then the problem is an excess of
unconjugated bilirubin, and the location of the problem is upstream of
bilirubin excretion. Hemolysis, viral hepatitis, or cirrhosis can be suspected.
– If direct bilirubin is elevated, then the liver is conjugating bilirubin normally,
but is not able to excrete it. Bile duct obstruction by gallstones or cancer
should be suspected.
Serum Proteins
• Total protein
– measures the amount of proteins in the bloodstream. Many different things
can cause abnormally high or low protein levels. A doctor may order total
protein testing to help diagnose kidney or liver disease, blood cancer,
malnutrition or abnormal body swelling. Two of the main proteins found in
the bloodstream are albumin and globulin.
• Globulins
– are made by various liver cells and the immune system. They help to fight off
infections. Low globulin levels can have many causes other than liver damage.
• Albumin
– is a protein made in the liver. If the liver is badly damaged, it can no longer
produce albumin. Albumin maintains the amount of blood in the veins and
arteries. When albumin levels become very low, fluid can leak out from the
blood vessels into nearby tissues, causing swelling in the feet and ankles.
Very low levels of albumin may be a sign of liver damage.
Amylase
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Amylase is primarily performed to diagnose or monitor diseases of the pancreas. It
may also detect some digestive tract problems.
Amylase is an enzyme that helps digest glycogen and starch. It is produced mainly
in the salivary glands and pancreas. When the pancreas is diseased or inflamed,
amylase escapes into the blood.
Drawn on a green Vacutainer
Increased amylase levels may indicate:
– Acute pancreatitis
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IN acute pancreatitis, amylase will elevate within the first 2 hours, peak by 24 hours and return to
normal 2-3 days after onset.
Cancer of the pancreas, ovaries, or lungs
Cholecystitis
Infection of the salivary glands (such as mumps) or an obstruction
Intestinal obstruction
Macroamylasemia
Pancreatic or bile duct obstruction
Perforated ulcer
Viral gastroenteritis
Decreased amylase levels may indicate:
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Damage to the pancreas
Kidney disease
Pancreatic cancer
Toxemia of pregnancy
Lipase
• Lipase is a pancreatic enzyme that changes fats and triglycerides
into fatty acids and glycerol.
• Greater-than-normal levels may indicate:
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Cholecystitis
Pancreatic cancer
Pancreatitis
Stomach ulcer or blockage
Viral gastroenteritis
• Lipase may also be increased in chronic pancreatitis and pancreatic
duct obstruction. Pancreatic duct obstruction by fibrous strictures,
stones, tumors, or edema increases the secretory pressure and
promotes extravasation of lipase into the pericapillary spaces.
Lipase is not specific for pancreatic disease and may be increased in
renal disease, acute cholecystitis, bowel obstruction, intestinal
infarction, duodenal ulcers, liver disease, alcoholism, diabetic
ketoacidosis, and after endoscopic retrograde
cholangiopancreatography.
• Drawn on a green Vacutainer
Coagulation Studies
• Prothrombin time- PT
– This test is used to evaluate the adequacy of the extrinsic coagulation
system and common pathway in the clotting mechanism.
– Prothrombin time (PT) test provides a control for long-term
anticoagulant therapy that usually involves the use of Coumadin.
• Partial Thromboplastin Time- PTT
– This test is used to evaluate the intrinsic coagulation system.
– It is also used to monitor heparin therapy.
• International Normalized Ratio- INR
– The ratio of a patient's prothrombin time to a normal (control) sample,
raised to the power of the ISI value for the analytical system used.
– The INR was devised to standardize the results,
which allows more accurate comparison
from hospital to hospital.
• Drawn on a blue Vacutainer
PT
• The prothrombin time is the time it takes plasma to
clot. This measures the quality of the extrinsic pathway
of coagulation.
• The speed of the extrinsic pathway is greatly affected
by levels of factor VII in the body. Factor VII has a short
half-life and its synthesis requires vitamin K.
• The prothrombin time can be prolonged as a result of
deficiencies in vitamin K, which can be caused by
warfarin, malabsorption, or lack of intestinal
colonization by bacteria. In addition, liver disease or
disseminated intravascular coagulation, DIC, may
prolong the PT.
PTT
• Normal PTTs may reflect normal clotting function.
• A decreased PTT
– results when coagulation factor VIII is elevated. This may
occur during an acute phase reaction, a condition causing
acute tissue inflammation or trauma. This is usually a
temporary change that is not monitored with the PTT.
When the condition causing the acute phase reaction is
resolved, the PTT will return to normal.
• A prolonged PTT
– clotting is taking longer to occur than expected and may be
caused by a variety of factors. Often, this suggests that
there may be a coagulation factor deficiency or a specific
or nonspecific inhibitor affecting the body’s clotting ability.
Coagulation factor deficiencies may be acquired or
inherited. Several factors are Vitamin K dependent.
Are elevated PT/PTT & INR ok?
• PT will be prolonged in patients receiving
Coumadin therapy
• PTT will be prolonged in patients receiving
Heparin therapy
• Indications for anticoagulant therapy
– DVT
– PE
– Afib
– Acute Coronary Syndrome
How high is too high?
• We like our patients to be adequately
anticoagulated when necessary, however it’s
true there can be too much of a good thing in
terms of anticoagulation
• Risks for elevated PT/PTT?
– Bleeding
– Bleeding
– Bleeding
– Did I mention bleeding?
Solutions to our bleeding problems
• Platelets
• Too much Coumadin?
– Try a little Vitamin K
• Too much heparin?
– How about some protamine sulfate!
D-Dimer
• D-dimer tests are ordered to help rule out, diagnose, and
monitor diseases and conditions that cause
hypercoagulability.
• A positive D-dimer indicates the presence of an abnormally
high level of fibrin degradation products in your body.
• An elevated D-dimer may be due to a DVT, PE or DIC but it
may also be due to a recent surgery, trauma, or infection.
– a negative (normal) d-Dimer nearly rules out the possibility that
a blood clot is actively forming.
– an elevated d-Dimer does not exclusively indicate that a blood
clot is forming; rather an elevated d-Dimer result means that
additional testing may be needed to see if a blood clot exists.
• Elevated levels are also seen with liver disease, pregnancy,
eclampsia, heart disease, and some cancers.
• Drawn on a blue Vacutainer