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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)

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Page 1: Commonly ordered laboratory tests What it is? Common Interpretations Nursing Implications & Specimen collection (there is some variation from hospital

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)

Page 2: Commonly ordered laboratory tests What it is? Common Interpretations Nursing Implications & Specimen collection (there is some variation from hospital

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

– RBC– HGB– HCT– MCV– MCH– Plt

• Purple Vacationer

Page 3: Commonly ordered laboratory tests What it is? Common Interpretations Nursing Implications & Specimen collection (there is some variation from hospital

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.

Page 4: Commonly ordered laboratory tests What it is? Common Interpretations Nursing Implications & Specimen collection (there is some variation from hospital

• 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

Page 5: Commonly ordered laboratory tests What it is? Common Interpretations Nursing Implications & Specimen collection (there is some variation from hospital

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.

Page 6: Commonly ordered laboratory tests What it is? Common Interpretations Nursing Implications & Specimen collection (there is some variation from hospital

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.

Page 7: Commonly ordered laboratory tests What it is? Common Interpretations Nursing Implications & Specimen collection (there is some variation from hospital

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.

Page 8: Commonly ordered laboratory tests What it is? Common Interpretations Nursing Implications & Specimen collection (there is some variation from hospital

Hemaglobin abnormalities• 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

Page 9: Commonly ordered laboratory tests What it is? Common Interpretations Nursing Implications & Specimen collection (there is some variation from hospital

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

Page 10: Commonly ordered laboratory tests What it is? Common Interpretations Nursing Implications & Specimen collection (there is some variation from hospital

MCV & MCHMean 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

Page 11: Commonly ordered laboratory tests What it is? Common Interpretations Nursing Implications & Specimen collection (there is some variation from hospital

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

Page 12: Commonly ordered laboratory tests What it is? Common Interpretations Nursing Implications & Specimen collection (there is some variation from hospital

Remember this????

Page 13: Commonly ordered laboratory tests What it is? Common Interpretations Nursing Implications & Specimen collection (there is some variation from hospital

BMPBasic Metabolic Panel

aka Astra 8 & Chem 7

• 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.

• BMP– Glucose – Calciulm– Sodium– Potassium– Carbon Dioxide– Chloride– BUN– Creatinine

• Green Vacutainer

Page 14: Commonly ordered laboratory tests What it is? Common Interpretations Nursing Implications & Specimen collection (there is some variation from hospital

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.

Page 15: Commonly ordered laboratory tests What it is? Common Interpretations Nursing Implications & Specimen collection (there is some variation from hospital

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.

• Hyperthyroidism• Tuberculosis• Prolonged immobilization • Excess Vitamin D intake • Kidney transplant

Page 16: Commonly ordered laboratory tests What it is? Common Interpretations Nursing Implications & Specimen collection (there is some variation from hospital

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.

Page 17: Commonly ordered laboratory tests What it is? Common Interpretations Nursing Implications & Specimen collection (there is some variation from hospital

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

Page 18: Commonly ordered laboratory tests What it is? Common Interpretations Nursing Implications & Specimen collection (there is some variation from hospital

Signs/Sypmtoms & Complications of hypocalcemia

• 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

Page 19: Commonly ordered laboratory tests What it is? Common Interpretations Nursing Implications & Specimen collection (there is some variation from hospital

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

Page 20: Commonly ordered laboratory tests What it is? Common Interpretations Nursing Implications & Specimen collection (there is some variation from hospital

Sodium

• 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.

Page 21: Commonly ordered laboratory tests What it is? Common Interpretations Nursing Implications & Specimen collection (there is some variation from hospital

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

Page 22: Commonly ordered laboratory tests What it is? Common Interpretations Nursing Implications & Specimen collection (there is some variation from hospital

Signs/Symptoms & Complications of hypernatremia

• Lethargy• Weakness• Irritability• Edema• Dry mucous membranes• Thirst• Restlessness• Seizures• Coma

Page 23: Commonly ordered laboratory tests What it is? Common Interpretations Nursing Implications & Specimen collection (there is some variation from hospital

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.

Page 24: Commonly ordered laboratory tests What it is? Common Interpretations Nursing Implications & Specimen collection (there is some variation from hospital
Page 25: Commonly ordered laboratory tests What it is? Common Interpretations Nursing Implications & Specimen collection (there is some variation from hospital

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

Page 26: Commonly ordered laboratory tests What it is? Common Interpretations Nursing Implications & Specimen collection (there is some variation from hospital

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

Page 27: Commonly ordered laboratory tests What it is? Common Interpretations Nursing Implications & Specimen collection (there is some variation from hospital

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.

Page 28: Commonly ordered laboratory tests What it is? Common Interpretations Nursing Implications & Specimen collection (there is some variation from hospital

Common causes of Hyperkalemia• 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 .

Page 29: Commonly ordered laboratory tests What it is? Common Interpretations Nursing Implications & Specimen collection (there is some variation from hospital

Signs & Symptoms of hyperkalemia

• 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

Page 30: Commonly ordered laboratory tests What it is? Common Interpretations Nursing Implications & Specimen collection (there is some variation from hospital

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.

Page 31: Commonly ordered laboratory tests What it is? Common Interpretations Nursing Implications & Specimen collection (there is some variation from hospital

Common causes of Hypokalemia

• 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.

Page 32: Commonly ordered laboratory tests What it is? Common Interpretations Nursing Implications & Specimen collection (there is some variation from hospital

Signs/Symptoms & Complications of hypokalemia

• 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.

Page 33: Commonly ordered laboratory tests What it is? Common Interpretations Nursing Implications & Specimen collection (there is some variation from hospital

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.

Page 34: Commonly ordered laboratory tests What it is? Common Interpretations Nursing Implications & Specimen collection (there is some variation from hospital

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.

Page 35: Commonly ordered laboratory tests What it is? Common Interpretations Nursing Implications & Specimen collection (there is some variation from hospital

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.

Page 36: Commonly ordered laboratory tests What it is? Common Interpretations Nursing Implications & Specimen collection (there is some variation from hospital

Common causes of both elevated & decreases CO2/HCO3

• Increased CO2– Severe vomiting , dehydration– Lung diseases – Cushing’s syndrome – Conn’s syndrome– Metabolic alkalosis

• Decreased CO2– Addison’s disease – Chronic diarrhea, malnutrion– Diabetic ketoacidosis – Metabolic acidosis – Kidney disease – Ethylene glycol or methanol poisoning – Salicylate (aspirin) overdose – Burns– Shock

Page 37: Commonly ordered laboratory tests What it is? Common Interpretations Nursing Implications & Specimen collection (there is some variation from hospital

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

Page 38: Commonly ordered laboratory tests What it is? Common Interpretations Nursing Implications & Specimen collection (there is some variation from hospital

Signs/Symptoms & Complications of elevated CO2/HCO3

• 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.

Page 39: Commonly ordered laboratory tests What it is? Common Interpretations Nursing Implications & Specimen collection (there is some variation from hospital

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!!!!

Page 40: Commonly ordered laboratory tests What it is? Common Interpretations Nursing Implications & Specimen collection (there is some variation from hospital

Chloride• 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

Page 41: Commonly ordered laboratory tests What it is? Common Interpretations Nursing Implications & Specimen collection (there is some variation from hospital

Causes of chloride imbalances• 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

Page 42: Commonly ordered laboratory tests What it is? Common Interpretations Nursing Implications & Specimen collection (there is some variation from hospital

Signs/symptoms & treatments of hyperchloremia

• S/S:– 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.

Page 43: Commonly ordered laboratory tests What it is? Common Interpretations Nursing Implications & Specimen collection (there is some variation from hospital

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

Page 44: Commonly ordered laboratory tests What it is? Common Interpretations Nursing Implications & Specimen collection (there is some variation from hospital

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.

Page 45: Commonly ordered laboratory tests What it is? Common Interpretations Nursing Implications & Specimen collection (there is some variation from hospital

Increased BUN• 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.

Page 46: Commonly ordered laboratory tests What it is? Common Interpretations Nursing Implications & Specimen collection (there is some variation from hospital

Decreased BUN• A decreased BUN may be seen in:

– 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.

Page 47: Commonly ordered laboratory tests What it is? Common Interpretations Nursing Implications & Specimen collection (there is some variation from hospital

Signs/Symptoms & Complications of abnormal BUN

• 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

Page 48: Commonly ordered laboratory tests What it is? Common Interpretations Nursing Implications & Specimen collection (there is some variation from hospital

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

Page 49: Commonly ordered laboratory tests What it is? Common Interpretations Nursing Implications & Specimen collection (there is some variation from hospital

BUN to Creatinine Ratio• 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)

Page 50: Commonly ordered laboratory tests What it is? Common Interpretations Nursing Implications & Specimen collection (there is some variation from hospital

Signs/Symptoms of elevated creatinine level

• 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

Page 51: Commonly ordered laboratory tests What it is? Common Interpretations Nursing Implications & Specimen collection (there is some variation from hospital

Easiest slide ever…

• Low concentrations of creatinine in serum have no profound clinical significance

Page 52: Commonly ordered laboratory tests What it is? Common Interpretations Nursing Implications & Specimen collection (there is some variation from hospital

Nursing Implications R/T abnormal BUN & Creatinine

• Strict I&O’s• Fluid restriction if indicated• Daily weight’s• Monitor Daily Lab values• Telemetry monitoring if indicated

Page 53: Commonly ordered laboratory tests What it is? Common Interpretations Nursing Implications & Specimen collection (there is some variation from hospital

I am so over the BMP!!!!

Page 54: Commonly ordered laboratory tests What it is? Common Interpretations Nursing Implications & Specimen collection (there is some variation from hospital

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 B-type 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

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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 – pulmonary embolus, – primary pulmonary hypertension,– chronic renal failure,– cirrhosis– hormone replacement therapy

• BNP levels more than 500 pg/mL are most consistent with CHF.

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Signs/Symptoms & Nursing Implications of elevated BNP

• Think CHF– Sob– Edema– HTN– Orthopnea – Etc, etc

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LFT

• Drawn on a green Vacutainer• Liver Function Test– Alanine transaminase- ALT– Aspartate transaminase- AST– Alkaline phosphatase- ALP– Total bilirubin- TBIL– Direct bilirubin– Total Protein– Albumin– Globulins

Page 58: Commonly ordered laboratory tests What it is? Common Interpretations Nursing Implications & Specimen collection (there is some variation from hospital

I love my liver

Page 59: Commonly ordered laboratory tests What it is? Common Interpretations Nursing Implications & Specimen collection (there is some variation from hospital

• 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.

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Elevation of the A’s…

• 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

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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.

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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.

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Amylase • 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• 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:– Damage to the pancreas– Kidney disease– Pancreatic cancer– Toxemia of pregnancy

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Lipase• Lipase is a pancreatic enzyme that changes fats and triglycerides into fatty

acids and glycerol.• Greater-than-normal levels may indicate:

– 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

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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

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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.

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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.

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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

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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?

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Solutions to our bleeding problems• Platelets

• Too much Coumadin?– Try a little Vitamin K

• Too much heparin?– How about some protamine sulfate!

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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

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