N-Trivia

Pelvic Laparoscopy
Alpha-fetoprotein Blood Test
Arterial Blood Gas Analysis

Posted: 05 Sep 2010 12:40 AM PDT

Laparoscopy permits visualization of the peritoneal cavity by the insertion of a small fiber-optic telescope (laparoscope) through the anterior abdominal wall. This surgical technique may be used diagnostically to detect abnormalities, such as cyst, adhesions, fibroids, and infection. It can also be used therapeutically to perform procedures, such as adhesion lysis; ovarian biopsy; tubal sterilization; removal of ectopic pregnancies, fibroids, hydrosalpinx, and foreign bodies; and fulguration of endometriotic implants.

Laparoscopy has largely replaced laparotomy because it requires a smaller incision, is faster, and reduces the risk of postoperative adhesions. Potential risks of laparoscopy include a punctured visceral organ, causing bleeding or spilling of intestinal contents into the peritoneum.

Purpose

To identify cause of pelvic pain.
To detect endometriosis, ectopic pregnancy, or pelvic inflammatory disease (PID).
To evaluate pelvic masses.
To evaluate infertility.
To stage a carcinoma.

Procedure

Preparation

Explain the procedure to the patient, and tell her that laparoscopy is used to detect abnormalities of the uterus, fallopian tubes, and ovaries.
Instruct the patient to fast for at least 8 hours before surgery.
Tell the patient who will perform the procedure and where it will take place.
Tell the patient whether she'll receive a general anesthetic and whether the procedure will require an outpatient visit or overnight hospitalization.
Warn the patient that she may experience pain at the puncture site and in the shoulder.
Make sure that the patient or a responsible family member has signed an informed consent form.
Check the patient's history for hypersensitivity to the anesthetic.
Make sure laboratory work is completed and results are reported before the test.
Instruct the patient to empty her bladder just before the test.

Implementation

The patient is anesthetized and placed in the lithotomy position.
The doctor catheterizes the bladder and then performs a bimanual examination of the pelvic area to detect abnormalities that may contraindicate the test and to ensure that the bladder is empty.
The doctor makes an incision at the inferior rim of the umbilicus. He inserts a special needle into the peritoneal cavity and insufflates 2 to 3 liters of carbon dioxide or nitrous oxide.
The doctor then removes the needle and inserts a trocar and sheath into the peritoneal cavity.
After removing the trocar, the doctor inserts the laparoscope through the sheath to examine the pelvis and abdomen.
To evaluate tubal patency, the doctor infuses a dye through the cervix and observes the fimbria (the fingerlike extremity of the fallopian tube) for spillage.
After the examination, he may perform minor surgical procedures such as ovarian biopsy.
The doctor may insert a second trocar at the pubic hairline to provide a channel for inserting other instruments.

Nursing Interventions

Instruct the patient to resume his usual diet.
Instruct the patient to restrict activity for 2 to 7 days.
Explain that abdominal and shoulder pain should disappear within 24 to 36 hours.
Provide analgesics.
Monitor vital signs.
Monitor the patient for adverse reactions to anesthetic.
Monitor intake and output.
Watch for bleeding and signs and symptoms of infection.

Interpretation

Normal Results

The uterus and fallopian tubes are of normal size and shape, free form adhesions, and mobile.
The ovaries are of normal size and shape; cysts and endometriosis are absent.
Dye injected through the cervix flows freely from the fimbria.

Abnormal Results

A bubble on the surface of the ovary suggests a possible ovarian cyst.
Sheets of strands of tissue suggest possible adhesions.
Small, blue powder burns on the peritoneum or serosa suggest endometriosis.
Growths on the uterus suggest fibroids.
An enlarged fallopian tube suggests possible hydrosalphinx.
An enlraged fallopian tube suggests a possible ectopic pregnancy.
Infection or abscess suggests possible pelvic inflammation disease.

Precautions

Be aware that laparoscopy is contraindicated in the patient with advanced abdominal wall cancer, advanced pulmonary or cardiovascular disease, intestinal obstruction, palpable abdominal mass, large abdominal hernia, chronic tuberculosis, or a history of peritonitis.
During the procedure, check for proper catheter drainage.

Interfering Factors

Adhesions or marked obesity which may obstruct to visualization.
Tissue or fluid becoming attached to the lens that may also obstruct to visualization.

Complications

Punctured visceral organ.
Peritonities.

Alpha-fetoprotein Blood Test

Posted: 05 Sep 2010 12:27 AM PDT

Alpha-fetoprotein (AFP) is a glycoprotein produced by fetal tissue and tumors that differentiate from midline embryonic structures. During fetal development, AFP levels in serum and amniotic fluid rise; because this problem crosses the placenta, it appears in maternal serum. In late stages of pregnancy, AFP levels in fetal and maternal serum and in amniotic fluid begin to diminish. During the first year of life, serum AFP levels continue to decline and usually remain how low thereafter.

High maternal serum AFP levels may suggest fetal tube defects, such as spina bifida and anencephaly; but positive confirmation requires amniocentesis and ultrasongraphy. Other congenital anomalies, such as Down syndrome and other chromosomal disorders, may be associated with low maternal serum AFP concentrations.

Elevated serum AFP levels in 70% of nonpregnant persons may indicate hepatocellular carcinoma (although low AFP levels don't rule it out) or germ cell tumor of gonadal, retroperitoneal, or mediastinal origin.

Serum AFP level rises in patients with ataxiatelangiectasia and in patients with cancer of the pancreas, stomach, or biliary system. Transient modest elevations can occur in nonneoplastic hepatocellular disease, such as alcoholic cirrhosis and acute or chronic hepatitis. Elevation of AFP levels after remission suggests tumor recurrence.

Purpose

To monitor the effectiveness of therapy in malignant conditions, such as hepatomas and germ cell tumors, and certain nonmalignant conditions such as ataxiatelengiectasia.
To screen those patients needs amniocentesis or high-resolution ultrasonography during pregnancy.

Procedure

Preparation

Explain that the AFP tests helps in monitoring fetal development, screens for a need for further testing, helps detect possible congenital defects in the fetus, and monitors the patient's response to therapy by measuring a specific blood protein, as appropriate.
Inform the patient that she need not restrict food, fluids, or medications.
Tell the patient that the test requires a blood sample. Explain who will perform the venipuncture and when.
Explain to the patient that she may experience slight discomfort from the tourniquet and needle puncture.

Implementation

Perform a venipuncture and collect the sample in a 7 ml clot-activator tube.
Record the patient's age, race, weight, and week of gestation on the laboratory request.
Handle the sample gently to prevent hemolysis.

Nursing Interventions

Place the patient in comfortable position.
Encourage deep breathing exercise to alleviate fear.
Apply direct pressure to the venipuncture site until bleeding stops.

Interpretation

Normal Results

When testing by immunoassay, AFP values are less than 15 ng/ml (SI, <15 mg/l) in male patients and nonpregnant female patients.
Values in maternal serum normally are less 25 ng/ml (SI, 25 ug/L). At 15 to 18 weeks gestation, values range from 10 to 150 ng/ml (SI, 10 to 150 ug/L).

Abnormal Results

Elevated maternal serum AFP level may suggest neural tube defect or other tube anomalies.
Definitive diagnosis requires ultrasonography and amniocentesis.
High AFP levels may indicate intrauterine death, or high levels indicate other anomalies, such as duodenal atresia, omphalocele, tetralogy of fallot, and Tuner's syndrome.
Elevated serum AFP levels occur in 70% of nonpregnant patients with hepatocellular carcinoma.
Elevated levels are also related to germ cell tumor of gonadal, retroperitoneal, or mediastinal origin.
Transient modest elevations can occur in nonneoplastic hepatocellular disease, such as alcoholic cirrhosis and acute or chronic hepatitis.
Elevation of AFP levels after remission suggests tumor recurrence.

Precautions

Handle the sample gently to prevent hemolysis.

Interfering Factors

Hemolysis from rough handling of the sample.
Multiple pregnancies that may cause false positive result.

Complication

Hematoma at the venipuncture site.

Arterial Blood Gas Analysis

Posted: 05 Sep 2010 12:18 AM PDT

Arterial blood gas (ABG) analysis evaluates gas exchange in the lungs by measuring the partial pressures of oxygen (PaO2) and carbon dioxide (Paco2) as well as the pH of an arterial sample. Pao2 measures the pressure exerted by the oxygen dissolved in the blood and evaluates the lungs' ability to oxygenate the blood.

Paco2 measures the pressure exerted by carbon dioxide dissolved in the blood and reflects the adequacy of ventilation by the lungs. The pH measures the bloods hydrogen ion concentration and is carbonate (HCO3-) is a measure of the bicarbonate ion concentration in the blood, which is regulated by the kidneys. Oxygen saturation (Sa02) is the oxygen content of the blood expressed as a percentage of the oxygen capacity which is the amount of oxygen then blood is capable of carrying if all of the hemoglobin [Hb] were fully saturate). Oxygen content (o2CT) measures the actual amount of oxygen in the blood and isn't commonly used in blood gas evaluation.

Purpose

To evaluate the efficiency of pulmonary gas exchange.
To assess the integrity of the ventilatory control system.
To determine the acidbase level of the blood.
To monitor respiratory therapy.

Procedure

Patient Preparation

Explain the arterial blood gas analysis evaluates how well the lungs are delivering the oxygen to the blood and eliminating carbon dioxide.
Tell the patient that the test requires a blood sample.
Explain to the patient, who will perform the arterial puncture, when it will occur, and where the puncture site will be; radial, brachial, or femoral artery.
Inform the patient that he may not need to restrict food and fluids.
Instruct the patient to breathe normally during the test, and warn him that he may experience a brief cramping or throbbing pain at the puncture site.

Implementation

Use a heparinized blood gas syringe to draw the sample.
Perform an arterial puncture or draw blood from an arterial line.
Eliminate air from the sample, place it on ice immediately, and prepare to transport for analysis.
Note the flow rate of oxygen therapy and method of delivery.
Note the patient's rectal temperature.

Nursing Interventions

After applying pressure to the puncture site for 3 to 5 minutes and when bleeding has stopped, tape a gauze pad firmly over it.
If the puncture site is on the arm, don't tape the entire circumference because this may restrict circulation.
If the patient is receiving anticoagulants or has a coagulonopathy, apply pressure to the puncture site longer than 5 minutes if necessary.
Monitor vital signs and observe for signs of circulatory impairment.

Interpretation

Normal Results

Normal ABG values fall within this ranges.

· Pao2 – 80 to 100 mm Hg (SI, 10.6 to 13.3 kPa)

· Paco2 – 35 to 45 mm Hg (SI, 4.7 to 5.3 kPa)

· pH – 7.35 to 7.45 (SI, 7.35 to 7.45)

· O2CT – 15% to 23% (SI, o.15 to 0.23)

· Sao2 – 94% to 100% (SI, 0.94 to 1)

· HCO3- -22 to 25 mEq/L (SI, 22 to 25 mmol/L)

Abnormal Findings

Low Pao2, O2CT, and Sao2 levels and a high Paco2 may result from conditions that impair respiratory function, such as respiratory muscle weakness or paralysis, respiratory center inhibition (from head injury, brain tumor, or drug abuse), and airway obstruction possibly from mucus plug or a tumor.
Low readings may result from bronchiole obstruction caused by asthma or emphysema, from an abnormal ventilation perfusion ratio due to partially blocked alveoli or pulmonary capillaries, or from alveoli that are damaged or filled with fluid because of disease, hemorrhage, or near drowning.
When inspired air contains insufficient oxygen, Pao2, O2CT, and Sao2 decrease, but Paco2 may be normal. Such findings are common in pneumothorax, impaired diffusion between alveoli and blood.
Low O2CT – with normal Pao2, Sao2 and, possibly, Paco2 values – may result from severe anemia, decreased blood volume, and reduced hemoglobin oxygen carrying capacity.

Precautions

Wait at least 20 minutes before drawing arterial blood when starting, changing, or discontinuing oxygen therapy. After initiating or changing settings of mechanical ventilation or other extubation.
Before sending the sample to the laboratory, note on the laboratory request whether the patient was breathing room air or receiving oxygen therapy when the sample is collected.

Interfering Factors