Liver Blood Tests Index

5'-NucleoTidase ('5NT)

Purpose of the test:

• Distinguishes between disease of liver and disease of bones when source of elevated alkaline-phosphatase levels is uncertain;

• Helps differentiate between obstruction of bile ducts and acute liver-cell damage;

• Detects some forms of hepatitis when jaundice is not a symptom;

Patient preparation:

• Don't eat any food or drink any liquid for at least 12 hours before the test.

Time before test results available:

• Test requires only a few minutes in the laboratory. Time before results are reported to the doctor or patient varies from a few minutes to a few days.

Normal values:

• Adults--2 to 7u/liter

• Children's values may be lower than adult values

What "high" or "increased" may indicate:

• Common bile-duct obstruction

• Acute liver-cell damage

• Active cirrhosis

Taking these drugs may affect test results:

• Codeine

• Meperidine

• Morphine

• Phenothiazines

Other factors that may affect test results:

• Failure to fast overnight

• If tourniquet is applied on the arm too long (over 1 minute), it may cause an inaccurate test result. Request another sample to be collected to ensure accuracy.

Acid Phosphatase

Preparation:

• Do not take this test if you have had a rectal exam or prostatic massage within the last 48 hours

• Diet--Don't eat any food or drink any liquid for at least 12 hours before the test

Time before test results available:

• Test requires only a few minutes in the laboratory. Time before results are reported to the doctor or patient varies from a few minutes to a few days.

Values:

• Values for total acid phosphatase depend on the method and range of units. Tests are all quantitative chemical analyses, bearing the name of the developer of the test, such as Bodansky, King-Armstrong or Bessey-Lowery-Brock.

Normal values:

• 0 to 1.1 Bodansky units/ml

• 1 to 4 King-Armstrong units/ml

• 0.13 to 0.63 Bessey-Lowery-Brock (BLB) units/ml

What "high" or "increased" may indicate:

• Prostatic tumor which has spread

• Prostatic infarction

• Paget's disease

• Gaucher's disease

Other factors that may affect test results:

• Failure to fast overnight

• Recent prostate massage

• Catheterization

• Recent rectal exam

• If tourniquet is applied on the arm too long (over 1 minute), it may cause an inaccurate test result. Request another sample to be collected to ensure accuracy.

Alanine aminotransferase (ALT)

Purpose of the test:

• Helps detect and evaluate treatment of acute hepatic disease;

• Helps distinguish between myocardial and hepatic-tissue damage.

Preparation:

• Don't eat any food or drink any liquid for at least 12 hours before the test.

Time before test results available:

• Test requires only a few minutes in the laboratory. Time before results are reported to the doctor or patient varies from a few minutes to a few days.

Normal values:

• Men--10 to 32 u/liter

• Women--9 to 24u/liter

• Infants--Twice normal range of adults

What "high" or "increased" may indicate:

• Severe hepatitis

• Chronic hepatitis

• Early or improving acute viral hepatitis

• Infectious mononucleosis

• Intrahepatic cholestasis

• Cholecystitis

• Severe hepatic congestion due to heart failure

• Slight to moderately high levels may indicate any condition that produces acute hepatocellular injury.

Taking these drugs may affect test results:

• Barbiturates

• Chlorpromazine

• Codeine

• Griseofulvin

• Isoniazid

• Meperidine

• Methyldopa

• Morphine

• Narcotic analgesics

• Nitrofurantoin

• Para-aminosalicylic acid

• Phenothiazines

• Phenytoin

• Salicylates

• Tetracycline

Other factors that may affect test results:

• Eating lead

• Exposure to carbon tetrachloride

• Failure to fast overnight

• If tourniquet is applied on the arm too long (over 1 minute), it may cause an inaccurate test result. Request another sample to be collected to ensure accuracy. 

Alkaline Phosphatase

Purpose of test:

• Detects and identifies skeletal disease, especially diseases characterized by rapidly growing bone;

• Detects liver diseases causing obstructions, such as a tumor or abscess;

• Assesses response to vitamin D in treating rickets caused by vitamin-D deficiency.

Patient preparation:

• Don't eat any food or drink any liquid for at leave 12 hours before the test.

Time before test results available:

• Test requires only a few minutes in the laboratory. Time before results are reported to the doctor or patient varies from a few minutes to a few days.

Normal values:
(Alkaline phosphatase levels measured by chemical inhibition range from):

• Men--90 to 239u/liter

• Women (under age 45)--76 to 196u/liter

• Women (over age 45)--87 to 250u/liter

• Children normally have levels up to 3 times higher than adults.

What "high" or "increased" may indicate:

• Acute or complete biliary obstruction

• Deficiency-induced rickets

• Osteomalacia

• Extensive bone metastases

• Hyperparathyroidsm

• Paget's disease

What "low" or "decreased" may indicate:

• Hypophosphatasia

• Protein deficiency

• Magnesium deficiency

Taking these drugs may affect test results:

• Albumin

• Barbiturates

• Chlorpropamide

• Halothane

• Isoniazid

• Methyldopa

• Oral contraceptives

• Phenothiazines

• Phenytoin

• Rifampin

Other factors that may affect test results:

• Healing long-bone fractures

• Age (infants, children, adolescents, women over 45)

• Failure to fast overnight

• If tourniquet is applied on the arm too long (over 1 minute), it may cause an inaccurate test result. Request another sample be collected to ensure accuracy. 
  

Anti-Nuclear Antibodies (ANA)

Purpose of test:

• Screens for systemic lupus erythematosus;

• Screens for several autoimmune disorders;

• Monitors effectiveness of treatment with drugs for sysstemic lupus erythematosus.

Patient preparation:

• None required

Time before test results available:

• 4 to 5 days

Normal values:

• Test for Ana is negative at a titer of 1:32 or below

What absence of ANA may indicate:

• Rules out systemic lupus erythematosus

What low titers may indicate:

• Viral diseases

• Liver disease

• Collagen-vascular disease

• Autoimmune disease

Taking these drugs may affect test results:

• Acetazolamide

• Aminosalicylic acid (PAS)

• Chlorothiazide

• Chlorpromazine

• Chlorprothixene

• Clofibrate

• Ethosuximide

• Gold salts

• Griseofulvin

• Hydralazine

• Isoniazid

• Mephenytoin

• Methyldopa

• Methysergide

• Oral contraceptives

• Para-aminosalicylic acid

• Penicillin

• Phenylbutazone

• Phenytoin

• Primidone

• Procainamide

• Propylthiouracil

• Wuinidine

• Reserpine

• Streptomycin

• Sulfonamides

• Tetracyclines

• Thiouracil

• Trimethadion

Other factors that may affect test results:

• If tourniquet is applied on the arm for too long (over 1 minute), it may cause an inaccurate test result. Request another sample to be collected to ensure accuracy. 
  

Arterial-Blood-Gas Analysis (ABG)

Purpose of the test:

• Evaluates gas exchange in the lungs;

• Measurements may be needed to make diagnosis or to monitor various treatments.

Risks and precautions:

• Some blood may leak from the artery after blood has been withdrawn. This is usually controlled easily.

• If you are treated with intermittent positive-pressure breathing, the operator should wait at least 20 minutes after treatment to draw arterial blood.

Patient preparation:

• None required if blood is collected from an artery in the arm. Partial disrobing is necessary if a technician, nurse or doctor chooses the artery in the groin or under the armpit.

Description of test:

• Operator feels the artery to be punctured. Skin over the artery is cleaned with alcohol or other antiseptic on a piece of cotton.

• The site is draped

• Skin is injected with a local anesthetic, such as Xylocaine

• The artery is punctured with a sterile, disposable needle attached to a disposable syringe. Operator withdraws the needle and transfers sample from the collecting syringe into sterile tubes.

• You will feel some minor pain when the local anesthetic is injected into the skin overlying the artery before collecting blood. You may feel slight additional discomfort when the underlying artery is punctured.

• Tubes are packed in an ice bag before transporting to the laboratory.

Immediate post-test care:

• Apply pressure to the puncture site

• Apply tape or guaze pad over the puncture site.

• Don't bandage the entire circumference of any puncture site.

Activity after test:

• Rest quietly for 10 minutes, applying pressure to arterial puncture site

• Use warm compresses if blood collects under the puncture site or if the area becomes tender, red or painful

Time before test results available:

• 1 to 2 hours if done in hospital or local lab. Several days if a distant lab analyzes samples.

Normal values:

• PaO2 75 to 100mmHg

• PaCO2 35 to 45mmHg

• pH 7.35 to 7.42

• O2CT 15 to 23%

• O2 94 to 100%

• HCO3 22 to 26mEq/liter

What "abnormal" may indicate:

• Pneumothorax

• Interstitial fibrosis

• Severe anemia

• Decreased blood volume and reduced hemoglobin/oxygen-carrying capacity

• Asphyxia

• Diarrhea

• Excess ingestion of antacids

• Hyperventilation

• Kidney disorders

• Liver disease

• Loss of electrolytes from excessive vomiting

• Respiratory stimulation by drugs

• Severe infections

• Shock

Taking these drugs may affect test results:

• Acetazolamide

• Antacids

• Bicarbonate

• Ethancrynic acid

• Hydrocortisone

• Methicillin

• Metolazone

• Nitrofurantoin

• Prednisone

• Tetracycline

• Thiazide diuretics

Other factors that may affect test results:

• None expected
    

Aspartate aminotransferase
(AST, formerly SGOT)

Purpose of the test:

• Helps diagnose recent severe heart problem

• Helps detect and differentiate between varying forms of liver disease

Preparation:

• Do not engage in strenuous exercise before the test

• Don't eat any food or drink any liquid for at lease 12 hours before the test

Normal values:

Test values are more meaningful when correlated with test results for creatine phosphokinase and lactic dehydrogenase. Values fluctuate and may be transiently and minimally elevated during early phases of heart attack.
A rising level over several days means continuing damage
A decreasing level over several days means tissue repair

• 8 to 20u/liter

• Normal values for infants are 4 times higher than those of adults

What "high" or "increased" may indicate:

• Acute pancreatitis

• Acute viral hepatitis

• Alcoholic cirrhosis

• Chronic hepatitis

• Delirium tremens

• Dermatomyositis

• Drug-inducted liver injury

• Duchenne muscular dystrophy

• Extensive recent surgery

• Fatty liver

• Hemolytic anemia

• Metastatic hepatic tumor

• Pulmonary embolism

• Severe infectious mononucleosis

• Severe muscle trauma

• Severe myocardial infarction

• Severe passive liver congestion

Taking these drugs may affect test results:

• Acetaminophen, large doses

• Anti-tubercular agents

• Chlorpropamide

• Dicumarol

• Erythromycin

• Methyldopa

• Opiates

• Pyridoxine

• Salicylates

• Sulfonamides

• Vitamin A

Other factors that may affect test results:

• Strenuous exercise

• Muscle trauma

• Failure to fast overnight
    

Blood Bilirubin:

Purpose of the test:

• Test evaluates liver function and the condition of red blood cells

• Diagnoses jaundice

• Monitors progression of jaundice

• Helps confirm diagnosis of obstruction of the bile ducts

• Helps diagnose cause of anemia.

Preparation:

• Do not eat any food or drink and liquid for at least 12 hours before the test.

Time before test results available:

• Test requires only a few minutes in the laboratory. Time before results are reported to the doctor varies from a few minutes to a few days.

Normal Values:

• Adult indirect bilirubin levels--1.1 mg/dl or less

• Adult direct bilirubin levels--Less than 0.5 mg/dl

• Total bilirubin in a newborn--1 to 12mg/dl

What "high" or "increased" may indicate:

• Congenital enzyme deficiencies (Gilbert's disease)

• Liver damage

• Severe hemolytic anemia

• Obstruction of bile ducts from stones or tumors

• If over 20mg/dl in a newborn, exchange transfusion may be needed

Taking these drugs may affect test results:

• Aminophenol

• Anti-malarials

• Ascorbic acid

• Dextran

• Epinephrine

• Ethoxazene

• Histidine

• Indican

• Isoproterenol

• Levodopa

• Methyldopa

• Novobiocin

• Phenazopyridine

• Phenelzine

• Primaquine

• Rifampin

• Streptomycin

• Sulfa drugs

• Theophylline

• Tyrosine

Other factors that may affect test results:

• Exposure to direct sunlight or ultraviolet light may increase bilirubin levels.

• Failure to fast overnight
   

Bleeding Time

(Note: Bleeding time is measured by one of four methods: Duke, Ivy, template, or modified template)

Purpose of test:

• Assesses overall platelet response to injury;

• Assesses functional capacity of vasoconstriction;

• Detects congenital and acquired blood disorders.

Risks and precautions:

• If bleeding doesn't stop in 15 minutes, the test is discontinued

• Incisions leave two small, hairline scars that are barely visible when healed

• If blood-pressure cuff is applied on the arm too long (over 1 minute), it may cause an inaccurate test result. Request another sample to be collected to ensure accuracy

Patient preparation:

• Do not drink any alcohol for at least 24 hours before the test

Description of tests:

Duke:

• Small incisions are made in the ear lobe with a disposable lancet;

• Operator blots the site every 30 seconds and measures the time until bleeding stops.

Ivy:

• Operator wraps blood-pressure cuff around upper arm and inflates it to 40;

• Three small punctures are made in the lower arm with a disposable lancet;

• Operator blots the site every 30 seconds and measures (with a stop-watch) the bleeding time of each;

• The average of the three is reported.

Template and Modified Template:

• Operator wraps blood-pressure cuff around upper arm and inflates it to 40;

• Template is applied to the arm to make two incisions;

• Modified-template method uses a spring-loaded blade to make two incisions;

• Operator blots the site every 30 seconds and measures the time until bleeding stops.

Immediate post-test care:

• Apply pressure to the puncture site for 5 minutes.

Activity after test:

• If you have a bleeding tendency, such as hemophilia, keep a pressure bandage over the incision for 24 to 48 hours to prevent further bleeding;

• If you do not have a bleeding tendency, a piece of guaze with a bandage should be sufficient. Check the incision site frequently.

Time before test results available:

• Up to 30 minutes

Test values:

• Bleeding time depends on the elasticity of the blood-vessel wall and on the number and functional capacity of platelets.

Normal values:

• Ivy method--Bleeding time is 1 to 7 minutes;

• Duke method--Bleeding time is 1 to 3 minutes;

• Template method--Bleeding time is 2 to 8 minutes;

• Modified template method--Bleeding time is 2 to 10 minutes.

What "abnormal" may indicate:

• Hodgkin's disease

• Acute leukemia

• Disseminated intravascular coagulation

• Hemolytic disease of the newborn

• Purpura

• Liver disease

• Blood-factor deficiency

Taking these drugs may affect test results:

• Acetylsalicylic acid

• Anti-coagulants

• Anti-neoplastics

• Aspirin and aspirin compounds

• Dextran

• Non-narcotic analgesics

• Non-steroidal anti-inflammatory drugs

• Pantothenyl alcohol and derivatives

• Streptokinase-streptodornase

• Sulfonamides

• Thiazides
    

Blood Ferritin

Purpose of test:

• Screens for iron deficiency and iron overload

• Measures iron storage

• Distinguishes between iron deficiency and chronic inflammation

Patient preparation:

• None required

Time before test results are available:

• Test requires only a few minutes in the laboratory. Time before results are reported to the doctor or patient varies from a few minutes to a few days.

Normal values:

According to the Mayo Medical Laboratories, ferritin levels range as follows:

• Men--20 to 300ng/ml

• Women--20 to 120ng/ml

• Children 6 months to 15 years--7 to 140ng/ml

• Children 1 month--200 to 600ng/ml

• Newborns--25 to 200ng/ml

What "high" or "increased" may indicate:

• Acute or chronic infection or inflammation

• Chronic hemolytic anemia

• Chronic kidney disease

• Hodgkin's disease

• Iron overload

• Leukemia

• Liver disease, acute or chronic

What "low" or "decreased" may indicate:

• Iron deficiency

Taking these drugs may affect test results:

• None expected

Other factors that may affect test results:

• A recent blood transfusion may cause an increase in ferritin levels

• If tourniquet is applied on the arm too long (over 1 minute), it may cause an inaccurate test result. Request another sample be collected to ensure accuracy.
   

Blood Folic Acid
(Pteroylglutamic Acid, Folacin, Folate)

Purpose of the test:

• Helps confirm diagnosis of megaloblastic anemia

• Helps distinguish between folic-acid deficiency and vitamin B-12 deficiency

• Assesses the amount of folic acid stored during pregnancy.

An inadequate dietary intake can cause a deficiency, especially during pregnancy

Patient preparation:

• Don't eat any food or drink any liquid for at least 12 hours before the test. Do not drink any alcohol for 24 hours before the test.

Time before test results available:

• Test requires only a few minutes in the laboratory. Time before results are reported to the doctor or patient varies from a few minutes to a few days.

Normal values:

• Folic-acid values range from 2 to 14ng/ml

What "high" or "increased" may indicate:

• Leukemia

• Liver disease

What "low" or "decreased" may indicate:

• Inadequate ingestion of folic acid from natural sources (common in vegetarians)

• Malabsorption syndromes

• Hyperthyroidism

• Pernicious anemia

Taking these drugs may affect test results:

• Phenytoin

• Pyrimethamine

Other factors that may affect test results:

• Alcohol

• Failure to fast overnight

• If tourniquet is applied on the arm too long (over 1 minute), it may cause an inaccurate test result. Request another sample to be collected to ensure accuracy.
   

Blood Iron & Total Iron-Binding Capacity (TIBC)

Purpose of test:

• Gives a good estimate of total iron storage.

• Helps confirm diagnosis of hemochromatosis.

• Helps distinguish between iron-deficiency anemia and anemia caused by chronic disease.

• Provides information for evaluating nutritional status of children and adults.

Patient preparation:

• None required

Time before test results available:

• Test requires only a few minutes in the laboratory. Time before results are reported to the doctor or patient varies from a few minutes to a few days.

Normal values:

• Iron and total iron-binding capacity (TIBC) values are:

Iron TIBC Saturation

What "abnormal" may indicate:

• Iron deficiency

• Rheumatoid arthritis

• Iron overload

Taking these drugs may affect test results:

• ACTH

• Chloramphenicol

• Iron supplements

• Oral contraceptives

Other factors that may affect test results:

• If tourniquet is applied on teh arm too long (over 1 minute), it may cause an inaccurate test result. Request another sample to be collected to ensure accuracy.
   

Blood Protein Electrophoresis
(Protein, Albumin, Globulin)

Purpose of the test :

• To help confirm blood disorders, gastrointestinal disorders, kidney disorders, liver disease, protein deficiency, diagnosis of tumors.

Preparation:

• None specified

Time before test results available:

• Test requires only a few minutes in the laboratory. Time before results are reported to the doctor or patient varies from a few minutes to a few days.

Normal values:

• Protein--6.6 to 7.9g/dl

• Albumin fraction--3.3 to 4.5g/dl

• Alpha-1-globulin fraction--0.1 to 0.4g/dl

• Alpha-2-globulin ranges--0.5 to 1g/dl

• Beta globulin--0.7to 1.2g/dl

• Gamma globulin--0.5 to 1.6g/dl

What "high" or "increased" may indicate:

• Chronic inflammatory disease

• Chronic syphilis

• Collagen diseases

• Dehydration

• Diabetes mellitus

• Diabetic acidosis

• Early-stage Laennec's cirrhosis

• Fulminating and chronic infections

• Hodgkin's disease

• Monocytic leukemia

• Multiple myeloma

• Rheumatoid arthritis

• Subacute bacterial endocarditis

• Systemic lupus erythematosus

• Tuberculosis

• Vomiting and diarrhea

What "low" or "decreased may indicate:

• Acute cholecystitis

• Benzene and carbon-tetracholoride poisoning

• Blood dyscrasias

• Collagen diseases

• Congestive heart failure

• Diarrhea

• Diabetes mellitus, uncontrolled

• Essential hypertension

• Gastrointestinal disease

• Hemorrhage

• Hepatic disease

• Hepatic dysfunction

• Hodgkin's disease

• Hyperthyroidism

• Hypogammaglobulinemia

• Malabsorption

• Malnutrition

• Metastatic carcinoma

• Neoplastic and renal diseases

• Nephritis

• Nephrosis

• Peptic ulcer

• Plasma loss from burns

• Rheumatoid arthritis

• Sarcoidosis

• Surgical or traumatic shock

• Systemic lupus erythematosus

• Toxemia of pregnancy

Taking these drugs may affect test results:

• Cytotoxic agents

• Cytotoxin

• Cyclosporin

Other factors that may affect test results:

• Pregnancy

• Contrast dyes, such as sulfobromophthalein
    

Gamma Glutamyl Transferase (GGT)

Purpose of test:

• Provides information about liver disease

• Assesses liver function

• Distinguishes between bone-and-joint disease and liver disease when blood alkaline-phosphatase levels are elevated.

Patient preparation:

• Don't eat any food or drink any liquid for at least 12 hours before the test. Don't drink any alcohol for 48 hours before the test.

Time before test results available:

• Test requires only a few minutes in the laboratory. Time before results are reported to the doctor or patient varies from a few minutes to a few days.

Normal values:

• Men--6 to 37u/liter

• Women under 45--5 to 27u/liter

• Women over 45--6 to 37u/liter

What "high" or "increased" may indicate:

• Acute liver disease

• Acute pancreatitis

• Epilepsy

• Brain tumor

• Prostatic metastasis

• Renal disease

• Hepatic metastatic infiltrations

• Obstructive jaundice

• Possibly following myocardial infarction

Taking these drugs may affect test results:

• Aminoglycosides

• Barbiturates

• Clofibrate

• Oral contraceptives

• Pehnytoin

Other factors that may affect test results:

• Moderate intake of alcohol causes increased blood-GGT levels that may last for at least 60 hours.

• Failure to fast overnight

• If tourniquet is applied on the arm too long (over 1 minute), it may cause an inaccurate test result. Request another sample to be collected to ensure accuracy.
   

IsoCitrate Dehydrogenase (ICD)

Purpose of the test:

• Provides important information to assess presence and extent of liver damage

• Detects early viral hepatitis and infectious mononucleosis

• Distinguishes between liver disease and myocardial infarction when SGOT is elevated

Patient preparation:

• Don't eat any food or drink any liquid for at least 12 hours before the test. Do not drink any alcohol for 24 hours before test.

Time before test results available:

• Test requires only a few minutes in the laboratory. Time before results are reported to the doctor or patient varies from a few minutes to a few days.

Normal values:

• 1.2 to 7u/liter at 86F (30C), as measured by continuous monitoring

• Newborns may have blood levels 4 times higher than normal adult values in the first 2 weeks after birth

What "high" or "increased" may indicate:

• Acute viral hepatitis;

• Conditions that result in liver-cell damage, such as hepatitis, cirrhosis, and malignancies.

Taking these drugs may affect test results:

• Aminosalicylic acid

• Isoniazid

• Methotrexate

• Phenylbutazone

Other factors that may affect test results:

• Alcohol

• Failure to fast overnight

• If tourniquet is applied on the arm too long (over 1 minute), it may cause an inaccurate test result. Request another sample to be collected to ensure accuracy.
   

Lipoprotein-Cholesterol Fractionation
[Cholesterol, HDL (High-Density Lipoproteins) & LDL (Low-Density Lipoproteins)]

Purpose of the test:

• To assess the risk of coronary-artery disease.

Preparation:

• Avoid exercise for 12 to 14 hours before the test

• Eat a normal diet for 2 weeks before the test

• Don't eat any food or drink any liquid for 12 hours before the test

• Don't drink any alcohol for 24 hours before the test.

Time before test results available:

• Test requires only a few minutes in the laboratory. Time before results are reported to the doctor or patient varies from a few minutes to a few days.

Normal values:

• Desirable total blood cholesterol values below 200

• Desirable LDL values below 130

• The higher the percentage of HDL to total cholesterol the better

What "high" or "increased" may indicate:

• High HDL generally indicates a healthy state

• High LDL generally indicates a higher-than-average risk for developing coronary-artery disease

Taking these drugs may affect test results:

• Cholestyramine

• Clofibrate

• Colestipol

• Dextrothyroxine

• Disulfiram

• Estrogen

• Gemifibrozil

• Iodine

• Miconazole

• Niacin

• Oral contraceptives

• Phenothiazines (high doses)

• Probucol

• Salicylates

• Vitamin A

• Vitamin D

Other factors that may affect test results:

• Alcohol

• Any illness that occurs at the same time as the test, especially if accompanied by fever

• Recent surgery

• Myocardial infarction

• Presence of bilirubin, hemoglobin, salicylates, iodine, vitamins A and D and some other substances in sample

• Failure to follow diet restrictions and exercise limitations.
   

Plasma Ammonia

Purpose of the test:

• Evaluates liver function

• Helps monitor progression of severe liver disease and treatment effectiveness

• Diagnoses possibility of impending or established liver failure

Patient preparation:

• Don't eat any food or drink any liquid for at least 12 hours before the test

Activity after test:

• Liver disease may produce bleeding problems, so be sure bleeding stops at the site where blood was drawn. If bleeding continues, contact your doctor.

• If plasma-ammonia levels are high, be aware of any signs indicating an impending or established hepatic coma.

Time before test results available:

• 2 to 3 days

Normal values:

• Plasma-ammonia levels are less than 50mcg/dl

What "high" or "increased" may indicate:

• Bleeding from the gastrointestinal tract

• Congestive heart failure

• Erythroblastosis fetalis

• Reye's syndrome

• Sever liver disease leading to hepatic coma

Taking these drugs may affect test results:

• Acetazolamide

• Ammonium salts

• Furosemide

• Danamycin

• Lactulose

• Neomycin

• Thiazides

Other factors that may affect test results:

• Portacaval shunt

• Hyperalimentation

• If tourniquet is applied on the arm too long (over 1 minute), it may cause an inaccurate test result. Request another sample to ensure accuracy.
    

Plasma Thrombin Time
(Thrombin Clotting Time)

Purpose of the test:

• Detects fibrinogen deficiency or defect

• Helps confirm diagnosis of DIC and liver disease

• Monitors effectiveness of heparin, streptokinase, or urokinase treatment

Patient preparation:

• None required

Time before test results available:

• Test requires only a few minutes in the laboratory. Time before results are reported to the doctor or patient varies from a few minutes to a few days.

Normal values:

• Thrombin times range from 10 to 15 seconds. Test results are usually reported with a normal-control value.

What "high" or "increased" may indicate:

• Dysfibrinogenemia

• Effective heparin therapy

• Liver disease

• Hypofibrinogenemia

• If DIC is suspected, an additional test for fibrin split products is also necessary

Taking these drugs may affect test results:

• Anti-coagulants

• Heparin

Other factors that may affect test results:

• If tourniquet is applied on the arm too long (over 1 minute), it may cause an inaccurate test result. Request another sample to be collected to ensure accuracy.