Common Laboratory Values: The Main Points for Nursing Students
These are the most common laboratory values for adults. As a nurse, it is important to be able to recognize a value that is
normal versus abnormal, since these numbers provide imperative physiologic data about the patient. One of the first things you will review at the beginning of each shift is the laboratory panel of your patients in order to identify any nursing interventions that may be necessary. To communicate effectively with the physicians, this is information that you must know. It may be helpful to write
out a list of these values on a poster and hang it in your room throughout nursing school.
Red Blood Cell: Men 4.5-6.2 mill/mcl, Women 4-5.5 mill/mcl
-The number of circulating RBCs is important because they contain hemoglobin, which transports oxygen throughout the body.
Hematocrit(Hct): Men 42-52%, Women 35-47%
-Represents RBC mass, the volume percentage of RBCs in the blood.
Hemoglobin(Hgb): Men 14-16.5 g/dL, Female 12-15 g/dL
-Transports oxygen and carbon dioxide through the tissues. A low value represents the blood’s decreased ability to oxygenate the tissues, as a result of anemia or bleeding.
*Results of RBC, Hct, and Hgb should be evaluated simultaneously because they are affected by the same conditions. A
decrease may indicate anemia or hereditary blood disorder, such as hemophilia, the blood’s inability to clot effectively when bleeding. In increase indicates conditions resulting in polycythemia, which can be caused by dehydration, decreased oxygen, or an overproduction of RBCs by the bone marrow.
Platelets: 150,000- 400,000
-Plateletsaggregate to stop bleeding. Platelet counts are used to evaluate, diagnose, andmonitor bleeding disorders. A condition that decreases the platelet count calls for bleeding precautions, such as preventing falls or cuts to the skin.Platelets can be increased by conditions that increase inflammation, high altitudes, cold weather, or exercise.
White Blood Cell: 4,500- 11,000
-WBCs are part of the immune defense system and aid in the fight of infection. The WBC count indicates the degree of
response to a pathological process, and the differential can lead to a more specific diagnosis. A low WBC count may indicate leukemia or overwhelming sepsis where the body is unable to fight infection. If it is high, look at the differential to evaluate further:
· Neutrophils: 1,800-7,800 cells/mm^3
-An increase indicates a bacterial infection, which requires antibiotics.
· Bands: 0-700 cells/mm^3
-Bands are detectable for about 4 hours. An increase indicates a bad infection requiring IV antibiotics.
-Segs last longer than bands. An increase indicates oral antibiotics.
· Eosinophils: 0-450 cells/mm^3
-An increase indicates an allergy, which requires taking a history to discover the allergen.
· Basophils: 0-200 cells/mm^3
-Basophils store histamine, and increase during inflammation.
· Lymphocytes: 1,000-4,800 cells/mm^3
-An increase indicates a viral infection, which basically requires supportive care.
· Monocytes: 0-800 cells/mm^3
-Monocytes can develop into macrophages and destroy bacteria and viruses. They also recognize dangerous antigens the future. A high count indicates thatinfection is being fought within the body.
Sodium: 135-145 mEq/L
-A cation of extracellular fluid that contributes to homeostasis. It helps maintain osmotic pressure of extracellular fluid, regulate renal retention and excretion of water, maintain acid base balance, regulate potassium and chloride levels, stimulate neuromuscular reactions, and maintain systemic blood pressure. It will increase or decrease if any of these are disrupted by a physiologic process.
Potassium: 3.5-5.1 mEq/L
-An intracellular cation. It regulates cellular water balance, electrical conduction in muscle cells, and acid base balance. The kidneys retain or excrete potassium based on the body’s need.
Chloride: 98-107 mEq/L
-An anion of extracellular fluid that aids in osmotic pressure and water balance.
Calcium: 8.2-10.2 mg/dl
-The most abundant cation in the body that participates in most vital processes.
Phosphorus: 2.5-4.5 mg/dL
-An intracellular anion that plays a major role in cellular metabolism, maintenance of cell membranes, and formation of bones and teeth.
*The concentrations of calcium and phosphorus are inversely related.
Magnesium:1.6-2.6 mg/dL
-An intracellular cation that is required for protein synthesis, nucleic acid synthesis, and muscle contraction. It controls the absorption of sodium, potassium, calcium and phosphorus as well as the utilization of carbohydrate, lipid, and protein.
B.U.N. (Blood Urea Nitrogen): 7-25 mg/dl
-Urea is an end product of protein metabolism in the liver and is excreted by the kidneys. A buildup or excess of
urea in the blood means that the kidney is not able to excrete it efficiently. Elevated levels indicate a slowing of the glomerular filtration rate, which can be caused by many processes such as renal failure. Examples of reasons the BUN
would be decreased is in liver disease or with inadequate dietary protein.
Blood Creatinine: 0.6-1.3
-Creatinine is a product of metabolism that is taken out of the body through the kidneys. An abnormal level may indicate impaired
renal function or a disorder involving the muscles. Creatinine determines renal clearance, or the rate at which the kidneys are able to clear creatinine in the blood.
*BUN and creatinine are evaluated at the same time for comparison. Increased levels indicate the slowing of the glomerular filtration rate, but creatinine is a better measure of kidney function. BUN can be affected by factors such as diet, activity, and dehydration.
GFR:90 - 120 mL/min/1.73 m2
-Checks how well the kidneys are working by measuring how much blood/creatinine (waste) passes through the glomeruli each minute. Creatinine builds up in the blood if the kidneys are not able to excrete it. Consistent levels below 60 indicate
chronic kidney disease. A level below 15 indicates acute renal failure.
ALT:4-6 units/L
-Enzyme found primarily in the liver, but also in kidney cells, heart, pancreas, spleen, skeletal muscle, and RBCs.
AST: 0-35 units/L
-Enzyme found primarily in the liver and heart, but also in skeletal muscle, kidneys,
pancreas, and the brain.
*ALT and AST are liver enzymes that leak into the general circulation when the liver is injured. ALT is more specific to liver inflammation than AST.
Activated partial thromboblastin time (aPPT): 20-36 seconds, or 1.5-2.5X normal when taking heparin
-Results of clotting time which screens for deficiencies in clotting factors/ coagulation disorders and monitors HEPARIN therapy. If greater than 90 seconds, initiate bleeding precautions.
Prothrombin time (PT): 10-13 seconds
-Also measures clotting time, and evaluates the clotting of patients receiving WARFARIN/COUMADIN therapy. If longer than 30 seconds, initiate bleeding precautions.
INR:2-3 (PT/normal average)
-The patient PT time /normal patient average because the PT results depend on the laboratory’s method used. The INR
is calculated to measure the effectiveness of Coumadin.
GFR:90 - 120 mL/min/1.73 m2
-Checks how well the kidneys are working by measuring how much blood/creatinine (waste) passes through the glomeruli each minute. Creatinine builds up in the blood if the kidneys are not able to excrete it. Consistent levels below 60 indicate
chronic kidney disease. A level below 15 indicates acute renal failure.
Protein:6-8 g/dl
-Consist of amino acids which are essential to all physiologic functions. Plays a part in regulating metabolic processes, immunity, and water balance. Increased in chronic inflammatory and immune diseases. Decreased in cases such as burns,
liver disease, malnutrition, and edema.
Albumin:3.5-5 g/dl
-The main transport protein. Also maintains oncotic pressure. Increases with dehydration and diarrhea when there is a decrease of plasma water. Decreases with malnutrition, liver disease, inflammation, and chronic diseases.
*Serum protein decrease is more indicative of long term malnutrition, whereas serum albumin decrease indicates recent malnutrition.
D-Dimer:Less than 250 ng/ml
-Drawn to rule out the presence of a clot. An increase occurs with DVT, DIC, pulmonary embolism, or hypercoagulability of the
blood.
BNP:Less than 100
-Brain natriuretic peptides increase in the heart in response to increased ventricular pressure and volume, or stretching of the heart muscles. An increased level indicates congestive heart failure. The higher it is, the more severe.
References:
Leeuwen, A. M., Leth, D. J., & Durning, M. (2009). Davis's comprehensive handbook of laboratory and diagnostic tests: with nursing implications (3rd ed.). Philadelphia: F.A. Davis Co..
Silvestri, L. A. (2011). Saunders comprehensive review for the NCLEX-RN examination (5th ed.). St. Louis, Mo.: Elsevier/Saunders.
These are the most common laboratory values for adults. As a nurse, it is important to be able to recognize a value that is
normal versus abnormal, since these numbers provide imperative physiologic data about the patient. One of the first things you will review at the beginning of each shift is the laboratory panel of your patients in order to identify any nursing interventions that may be necessary. To communicate effectively with the physicians, this is information that you must know. It may be helpful to write
out a list of these values on a poster and hang it in your room throughout nursing school.
Red Blood Cell: Men 4.5-6.2 mill/mcl, Women 4-5.5 mill/mcl
-The number of circulating RBCs is important because they contain hemoglobin, which transports oxygen throughout the body.
Hematocrit(Hct): Men 42-52%, Women 35-47%
-Represents RBC mass, the volume percentage of RBCs in the blood.
Hemoglobin(Hgb): Men 14-16.5 g/dL, Female 12-15 g/dL
-Transports oxygen and carbon dioxide through the tissues. A low value represents the blood’s decreased ability to oxygenate the tissues, as a result of anemia or bleeding.
*Results of RBC, Hct, and Hgb should be evaluated simultaneously because they are affected by the same conditions. A
decrease may indicate anemia or hereditary blood disorder, such as hemophilia, the blood’s inability to clot effectively when bleeding. In increase indicates conditions resulting in polycythemia, which can be caused by dehydration, decreased oxygen, or an overproduction of RBCs by the bone marrow.
Platelets: 150,000- 400,000
-Plateletsaggregate to stop bleeding. Platelet counts are used to evaluate, diagnose, andmonitor bleeding disorders. A condition that decreases the platelet count calls for bleeding precautions, such as preventing falls or cuts to the skin.Platelets can be increased by conditions that increase inflammation, high altitudes, cold weather, or exercise.
White Blood Cell: 4,500- 11,000
-WBCs are part of the immune defense system and aid in the fight of infection. The WBC count indicates the degree of
response to a pathological process, and the differential can lead to a more specific diagnosis. A low WBC count may indicate leukemia or overwhelming sepsis where the body is unable to fight infection. If it is high, look at the differential to evaluate further:
· Neutrophils: 1,800-7,800 cells/mm^3
-An increase indicates a bacterial infection, which requires antibiotics.
· Bands: 0-700 cells/mm^3
-Bands are detectable for about 4 hours. An increase indicates a bad infection requiring IV antibiotics.
-Segs last longer than bands. An increase indicates oral antibiotics.
· Eosinophils: 0-450 cells/mm^3
-An increase indicates an allergy, which requires taking a history to discover the allergen.
· Basophils: 0-200 cells/mm^3
-Basophils store histamine, and increase during inflammation.
· Lymphocytes: 1,000-4,800 cells/mm^3
-An increase indicates a viral infection, which basically requires supportive care.
· Monocytes: 0-800 cells/mm^3
-Monocytes can develop into macrophages and destroy bacteria and viruses. They also recognize dangerous antigens the future. A high count indicates thatinfection is being fought within the body.
Sodium: 135-145 mEq/L
-A cation of extracellular fluid that contributes to homeostasis. It helps maintain osmotic pressure of extracellular fluid, regulate renal retention and excretion of water, maintain acid base balance, regulate potassium and chloride levels, stimulate neuromuscular reactions, and maintain systemic blood pressure. It will increase or decrease if any of these are disrupted by a physiologic process.
Potassium: 3.5-5.1 mEq/L
-An intracellular cation. It regulates cellular water balance, electrical conduction in muscle cells, and acid base balance. The kidneys retain or excrete potassium based on the body’s need.
Chloride: 98-107 mEq/L
-An anion of extracellular fluid that aids in osmotic pressure and water balance.
Calcium: 8.2-10.2 mg/dl
-The most abundant cation in the body that participates in most vital processes.
Phosphorus: 2.5-4.5 mg/dL
-An intracellular anion that plays a major role in cellular metabolism, maintenance of cell membranes, and formation of bones and teeth.
*The concentrations of calcium and phosphorus are inversely related.
Magnesium:1.6-2.6 mg/dL
-An intracellular cation that is required for protein synthesis, nucleic acid synthesis, and muscle contraction. It controls the absorption of sodium, potassium, calcium and phosphorus as well as the utilization of carbohydrate, lipid, and protein.
B.U.N. (Blood Urea Nitrogen): 7-25 mg/dl
-Urea is an end product of protein metabolism in the liver and is excreted by the kidneys. A buildup or excess of
urea in the blood means that the kidney is not able to excrete it efficiently. Elevated levels indicate a slowing of the glomerular filtration rate, which can be caused by many processes such as renal failure. Examples of reasons the BUN
would be decreased is in liver disease or with inadequate dietary protein.
Blood Creatinine: 0.6-1.3
-Creatinine is a product of metabolism that is taken out of the body through the kidneys. An abnormal level may indicate impaired
renal function or a disorder involving the muscles. Creatinine determines renal clearance, or the rate at which the kidneys are able to clear creatinine in the blood.
*BUN and creatinine are evaluated at the same time for comparison. Increased levels indicate the slowing of the glomerular filtration rate, but creatinine is a better measure of kidney function. BUN can be affected by factors such as diet, activity, and dehydration.
GFR:90 - 120 mL/min/1.73 m2
-Checks how well the kidneys are working by measuring how much blood/creatinine (waste) passes through the glomeruli each minute. Creatinine builds up in the blood if the kidneys are not able to excrete it. Consistent levels below 60 indicate
chronic kidney disease. A level below 15 indicates acute renal failure.
ALT:4-6 units/L
-Enzyme found primarily in the liver, but also in kidney cells, heart, pancreas, spleen, skeletal muscle, and RBCs.
AST: 0-35 units/L
-Enzyme found primarily in the liver and heart, but also in skeletal muscle, kidneys,
pancreas, and the brain.
*ALT and AST are liver enzymes that leak into the general circulation when the liver is injured. ALT is more specific to liver inflammation than AST.
Activated partial thromboblastin time (aPPT): 20-36 seconds, or 1.5-2.5X normal when taking heparin
-Results of clotting time which screens for deficiencies in clotting factors/ coagulation disorders and monitors HEPARIN therapy. If greater than 90 seconds, initiate bleeding precautions.
Prothrombin time (PT): 10-13 seconds
-Also measures clotting time, and evaluates the clotting of patients receiving WARFARIN/COUMADIN therapy. If longer than 30 seconds, initiate bleeding precautions.
INR:2-3 (PT/normal average)
-The patient PT time /normal patient average because the PT results depend on the laboratory’s method used. The INR
is calculated to measure the effectiveness of Coumadin.
GFR:90 - 120 mL/min/1.73 m2
-Checks how well the kidneys are working by measuring how much blood/creatinine (waste) passes through the glomeruli each minute. Creatinine builds up in the blood if the kidneys are not able to excrete it. Consistent levels below 60 indicate
chronic kidney disease. A level below 15 indicates acute renal failure.
Protein:6-8 g/dl
-Consist of amino acids which are essential to all physiologic functions. Plays a part in regulating metabolic processes, immunity, and water balance. Increased in chronic inflammatory and immune diseases. Decreased in cases such as burns,
liver disease, malnutrition, and edema.
Albumin:3.5-5 g/dl
-The main transport protein. Also maintains oncotic pressure. Increases with dehydration and diarrhea when there is a decrease of plasma water. Decreases with malnutrition, liver disease, inflammation, and chronic diseases.
*Serum protein decrease is more indicative of long term malnutrition, whereas serum albumin decrease indicates recent malnutrition.
D-Dimer:Less than 250 ng/ml
-Drawn to rule out the presence of a clot. An increase occurs with DVT, DIC, pulmonary embolism, or hypercoagulability of the
blood.
BNP:Less than 100
-Brain natriuretic peptides increase in the heart in response to increased ventricular pressure and volume, or stretching of the heart muscles. An increased level indicates congestive heart failure. The higher it is, the more severe.
References:
Leeuwen, A. M., Leth, D. J., & Durning, M. (2009). Davis's comprehensive handbook of laboratory and diagnostic tests: with nursing implications (3rd ed.). Philadelphia: F.A. Davis Co..
Silvestri, L. A. (2011). Saunders comprehensive review for the NCLEX-RN examination (5th ed.). St. Louis, Mo.: Elsevier/Saunders.