Lymph Node Biopsy Posted: 12 Sep 2010 08:37 PM PDT
Lymph node biopsy is the surgical excision of an active lymph node or needle aspiration of a nodal specimen for histological examination. Both techniques usually use local anesthesia and sample superficial nodes in the cervical, supraclavicular, axillary, or inguinal region. Excision, the preferred technique, provides a larger specimen. Microscopic examination of the tissue specimen distinguishes malignant from non malignant causes of lymph node enlargement. Hodgkin's disease, a lymphoma affecting the entire lymph system, is the leading cancer in adolescents and young adults. Lymph node malignancy may also result from metastatic cancer. Purpose of Lymph Node Biopsy - To determine the cause of lymph node enlargement.
- To distinguish between benign and malignant lymph node processes.
- To stage metastatic cancer.
Lymph Node Biopsy Procedure Preparation - Make sure the patient has signed an appropriate consent form.
- Note and report all allergies.
- Check the patient's history for hypersensitivity to anesthetic.
- For excisional biopsy, instruct the patient to restrict food from midnight and to drink clear liquids only.
- If the patient will receive a general anesthetic, tell him to restrict fluids.
- For a needle biopsy, no restriction of fluid or foods is necessary.
- Explain that the test takes 15 to 30 minutes.
Implementation Excisional Biopsy - Prepare the skin over the biopsy site, and drape the area for privacy.
- The doctor administers the anesthetic.
- Makes an incision, removes the entire node, and places it in a properly labeled bottle containing normal saline solution.
- After the biopsy, he sutures the wound and applies a sterile dressing.
Needle Biopsy - The doctor prepares the site and administers a local anesthetic.
- Grasps the node between thumb and forefinger, inserts the needle directly into the node, and obtains a small core specimen.
- Removes the needle and places the specimen in a properly labeled bottle containing normal saline solution.
- Pressure is exerted on the biopsy site to control bleeding, and an adhesive bandage is applied.
Nursing Interventions - Tell the patient to resume his usual diet and activity.
- Monitor vital signs.
- Watch for bleeding and infection
- Observe the biopsy site.
Interpretation Normal Results - Lymph node encapsulated by collagenous connective tissue and divided into smaller lobes by tissue strands (trabeculae).
- Outer cortex composed of lymphoid cells and nodules or follicles containing lymphocytes.
- Inner medulla composed of reticular phagocytic cells that collect and drain fluid.
Abnormal Results - Lymphatic cancer
- Hodgkin's disease
Interfering Factors - Inability to obtain representative tissue specimen.
- Inability to differentiate nodal disorder
Precautions - Storing the tissue specimen in normal saline solution instead of 10% formalin solution allows part of the specimen to be used for cytologic impression smears, which are studied along with the biopsy specimen.
Complications Related posts: - Breast Biopsy Procedure
- Bone Marrow Aspiration and Biopsy
- Thoracentesis
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Serum Uric Acid Test Posted: 12 Sep 2010 08:30 PM PDT
The uric acid test is used to measure serum uric acid levels, the major end metabolite of purine. Disorders of purine metabolism, rapid destruction of nucleic acids, and conditions marked by impaired renal excretion characteristically raise serum uric acid levels. The most specific laboratory method for detecting uric acid is spectrophotometric absorption after treatment of the specimen with the enzyme uricase. Purpose of Uric Acid Test - To confirm the diagnosis of gout.
- To help detect renal dysfunction.
Uric Acid Test Procedure Patient Preparation - Explain to the patient that the uric acid test detects gout and kidney dysfunction.
- Tell the patient that the test requires a blood sample.
- Explain who will perform the venipuncture and when.
- Notify the laboratory and the physician of drugs the patient is taking that may affect test results; it may be necessary to restrict them.
- Instruct the patient to fast for 8 hours before the test.
- Explain to the patient that he may experience slight discomfort from the tourniquet and the needle puncture.
Implementation - Perform a venipuncture and collect the sample in a 3-or-4 ml clot-activator tube.
Nursing Interventions - Apply direct pressure to the venipuncture site until bleeding stops.
- Inform the patient that he may resume his usual diet and medications stopped before the test.
Interpretation Normal Results - In men, 3.4 to 7 mg/dl (SI, 202 to 416 µmol/L)
- In women, 2.3 to 6 mg/dl (SI, 143 to 357 µmol/L)
Abnormal Results - Increased uric acid levels may indicate gout or impaired kidney function.
- Levels may also rise in hjeart failure, glycogen storage disease (type I, von Gierke's disease), infection, hemolytic and sickle cell anemia, polycythemia, neoplasms, and psoriasis.
- Low uric acid levels may indicate defective tubular absorption (such as Fanconi's syndrome) or acute hepatic atrophy.
Interfering Factors - Failure to observe patient restrictions
- Loop diuretics, ethambutol, vincristine, pyrazinamide, thiazines, and low doses of aspirin (possible increase).
- Acetaminophen, ascorbic acid, and levodopa (possible false-high if using colorimetric method)
- Aspirin in high doses (possible decrease).
- Starvation, high purine diet, stress, and alcohol abuse (possible increase).
Complication - Hematoma at the venipuncture site.
Precautions - Handle the blood sample gently to prevent hemolysis.
- Send the urine specimen to the laboratory immediately after collection is completed.
Related posts: - Serum Creatinine
- Thrombin Time Test
- Fasting Plasma Glucose
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Triglycerides Testing Posted: 12 Sep 2010 08:22 PM PDT
Serum triglyceride testing provides quantitative analysis of triglycerides, the main storage form of lipids, which constitute about 95% of fatty tissue. Although not in itself diagnostic, serum triglyceride analysis permits early identification of hyperlipidemia (characteristic in nephrotic syndrome and other conditions) and determination of the risk of coronary artery disease (CAD). Purpose of Triglycerides Testing - To screen for hyperlipidemia or pancreatitis.
- To help identify nephrotic syndrome and poorly controlled diabetes mellitus.
- To assess coronary artery disease (CAD) risk
- To calculate the lower-density lipoprotein cholesterol level using the Friedewald equation.
Triglycerides Testing Procedure Preparation - Explain to the patient that the triglyceride test is used to detect fat metabolism disorders.
- Tell the patient that the test requires a blood sample.
- Explain who will perform the venipuncture and when.
- Notify the laboratory and physician of drugs the patient is taking that may affect the test results; it may be necessary to restrict them.
- Instruct the patient to fast at least 12 hours before the test and abstain from alcohol for 24 hours. Tell him that he may drink water.
- Explain to the patient that he may experience slight discomfort from the tourniquet and the needle puncture.
Implementation - Perform a venipuncture and collect the sample in a 4-ml ethylenediaminetetraecetic acid tube.
- Send the sample to the laboratory immediately.
- Avoid prolonged venous occlusion; remove the tourniquet within 1 minute of application.
Nursing Interventions - Apply direct pressure to the venipuncture site until bleeding stops.
- If a hematoma develops at the venipuncture site, continue direct pressure.
- Tell that patient that he may resume his usual diet and medication that was discontinued before the test, as ordered.
Interpretation Normal Results - Varying levels, depending on age and sex
- In men, 44 to 180 mg/dl (SI, 0.44 to 2.01 mmol/L)
- In women, 10 to 190 mg/dl (SI, 0.11 to 2.21 mmol/L)
Abnormal Results - An increased or decreased serum triglycerides level is abnormal; additional tests are required for a definitive diagnosis.
- A mild to moderate increase in serum triglyceride levels indicates biliary obstruction, diabetes mellitus, nephrotic syndrome, or over consumption of alcohol.
- Markedly increased levels without an identifiable cause reflect congenital hyperlipoproteinemia and necessitate lipoprotein phenotyping to confirm the diagnosis.
- Decresed serum triglyceride levels are rare and occur mainly in malnutrition and abetalipoproteinemia.
Interfering Factors - Failure to observe pretest restrictions
- Use of glycol-lubricated collection tube
- Failure to send the sample to the laboratory immediately.
- Antilipenics (decresed serum levels)
- Cholestyramine and colestipol (decreased cholesterol levels but increased or unaffected triglycerides.
- Corticosteroids (long time use)
- Clofibrate ( decreased cholesterol and triglycerides levels)
- Probucol ( decresed cholesterol levels but variable effect on triglycerides levels).
Precautions - Avoid prolonged venous occlusion; remove the tourniquet within 1 minute of application.
Complication - Hematoma to the venipuncture site.
Related posts: - Serum Uric Acid Test
- Serum Creatinine
- Thrombin Time Test
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