Chapter 3 Diagnostic Procedure - Fall 2024-2025 PDF

Chapter 3 Diagnostic evaluation Fall 2024-2025 3-PULSE OXIMETER Is a noninvasive method of continuously monitoring the oxygen saturation of hemoglobin (SaO2). A disposable probe is attached to the fingertip, earlobe or bridge of the nose, SaO2: 95% - 100%. False or inaccurat...

Chapter 3 Diagnostic evaluation Fall 2024-2025 3-PULSE OXIMETER Is a noninvasive method of continuously monitoring the oxygen saturation of hemoglobin (SaO2). A disposable probe is attached to the fingertip, earlobe or bridge of the nose, SaO2: 95% - 100%. False or inaccurate readings may occur with: Shock states Vasoconstriction Hypothermia Compression of the artery during blood pressure measurement Elevated lipid levels Elevated venous pressure How Does a Pulse Oximeter Work? A pulse oximeter is a noninvasive monitoring device that can indirectly measure a person’s functional oxygen saturation (SpO2) and help with early detection of hypoxemia. Inside the pulse oximeter, there is a light source and a light detector. Pulse oximeters work by either transmitting light through tissue perfused by blood (ideally a site with a dense capillary bed like the fingertip). They are called pulse oximeters because they use the pulsations to discriminate between arterial blood and other tissue or venous blood. The probe on the pulse oximeter has light-emitting diodes (LEDs) which shine at least two types of light, red and infrared. The device is positioned so that the light shines through a translucent part of a patient’s body, such as a fingertip or earlobe, and measures the changing absorbance at each wavelength. Oxygenated hemoglobin absorbs more infrared light, whereas deoxygenated hemoglobin absorbs more red light. Since the absorption of light at these wavelengths differs between oxygenated and deoxygenated blood, the device can determine the absorbances due to just the arterial blood and thereby determine a patient’s peripheral oxygen saturation. The sensor inside a pulse oximeter uses the ratio of red light to infrared light (after the light passes through your finger) to measure your blood oxygen saturation levels. The light detector inside the pulse oximeter senses how much red light and how much infrared light is absorbed as the light passes through the finger and the red blood cells. The amount of light that the finger absorbs depends on several factors: The concentration of the substance that’s in between the light beams and the light detector The length of the light path in that substance The amount of oxygenated hemoglobin The amount of deoxygenation hemoglobin 4-Throat Culture It may performed to identify organisms responsible for pharyngitis or LRT infections. Throat swab or nasal swab may be taken in respiratory tract evaluation accompanied with fever and lymphadenopathy Staphylococcus or Haemophilus Influenza may be detected by Nasopharyngeal culture Quick strep test may performed within 15 minutes Results usually take between 48-72 hrs. Culture may be repeated to identify patient’s response to therapy 5-Sputum studies Culture and sensitivity (C/S) and gram stains are two laboratory test performed on sputum specimen. The specimen is cultured: to diagnose bacterial infection and identify pathogenic infection, Sensitivity test: determines whether the bacterial strain is resistant to certain antibiotics. Gram stain: is performed to determine whether the organisms are gram-negative or gram-positive. Because the results of a culture and sensitivity may take 24 to 48 hours, Gram stain is done and the result is available quickly (in a few hours) and is useful for selecting antibiotic therapy until the culture and sensitivity report is available. Expectoration is the usual method for collecting specimen. Technique: Sputum is collected early in the morning, at which time the sputum is more plentiful and concentrated from pooling while the patient slept. The specimen is put directly into a sterile container, and transported to the laboratory within 2 hours. Collection of Sputum: Direct Method: The patient cough voluntarily to produce sputum, if coughing fails to produce a specimen, breathing a heated nebulized mist of distilled water or NaCl for several minutes will liquify secretions enough to produce sputum. Indirect Method: (DTA: Deep Tracheal Aspiration). If patient is unable to cough a nasotracheal suction tube is inserted through a nostril and into the trachea. If patient is intubated DTA can be taken via suction tube. Gastric Lavage: Obtaining sputum by gastric lavage is occasionally necessary in uncooperative patients particularly very young children, and acutely ill patients suspected of having malignancy or tuberculosis. Nursing Care: Note the color, consistency, odor and mount of the sputum. Transforms the specimen directly to the lab. In obtaining sputum by the direct method, first have the patient brush teeth and gargle to reduce contamination with saliva and mouth bacteria. Instruct the patient to take a deep breath and exhale with a deep cough directly into the container. For nasotracheal suctioning: Assist the patient into a sitting position Administer oxygen during the procedure by nasal cannula Monitor the patient's cardiovascular and respiratory status during and after the procedure Imaging studies It includes: 5. Chest x-rays 6. CT scan ( Computed Tomography) 7. MRI ( Magnetic Resonance Imaging) 8. Fluoroscopic Studies (Fine needle aspiration biopsy) 9. Contrast studies ( Pulmonary angiography) 10. Radioisotope or Lung scans 5- Chest x-ray Are an essential diagnostic tool for evaluating disorders of the chest. it provides information regarding the anatomical location and appearance of the lung Indication: To diagnose: - Atelectasis, pleural effusion - Hemothorax or pneumothorax - Infiltration (pneumonia), - Thoracic fracture. - To detect foreign body - Checks response of patient treatment o It consists of two views: Posteroanterior and lateral projections - Nursing intervention: Usually taken after a deep breath because the lungs are best visualized when they are well aerated, If taken on expiration, x-ray films may accentuate an otherwise unnoticed pneumothorax or obstruction of a major artery. All metallic objects like jewellery should be removed before doing X-ray Pregnancy should be ruled out before the test 6- Ct scan( computed tomography) o Scanning is taken by narrow beam x-ray,It provides a cross sectional view of the chest.CT scan produces three dimensional images more details than chest X-rays. It may be used to: - determine small tumors that are not visible in C X R. - shows major contrasts between bone, soft tissues and air. - distinguish fine tissue density - define pulmonary nodules and small tumors o Contrast agents are useful when evaluating mediastinum and its contents, but the CT scan can be done with or without contraste.  Preparation: Removal of any metal object from the examination area Specific preparation for contrast media: -Hydration and fasting: - Sufficient hydration if risk of renal failure - Fasting for 4 to 6 hours to avoid vomiting that may be caused by the contrast medium - Lab tests: Assessment of renal function: determination of creatinine and urea - Informed consent should be signed by the patient before contrast injection - Treatment: stop oral antidiabetic drugs (metformin) 48 hours before the examination (Because metformin is excreted primarily by the kidneys, continued intake of metformin after the onset of renal failure results in a toxic accumulation of this drug and subsequent lactic acidosis.In patients with renal failure (acute or chronic), the renal clearance of metformin is decreased, and there is an associated risk of lactic acidosis. To avoid this complication, metformin must be withheld after the administration of the contrast agent for 48 hours, during which the contrast-induced renal failure becomes clinically apparent. If renal function is normal at 48 hours, the metformin can be restarted Antiallergic: premedication if known allergy Contra indicated in case of pregnancy, and in case of renal failure in case of contraste injection 7-Magnetic Resonance Imaging o MRIs are similar to CT scans except that magnetic fields and radio frequency signals are used instead of a narrow-beam x-ray. o It shows more detail imaging o It is used to: - Visualize soft tissue. - visualize bronchogenic carcinoma - to characterize pulmonary nodules, stage bronchogenic carcinoma (assessment of chest wall invasion) - To evaluate inflammatory activity in interstitial lung disease, acute pulmonary embolism, and chronic thrombolytic pulmonary hypertension * contraindication: – patient with metal prosthesis (e.g. hip prosthesis, pace Maker, mechanical heart valve....) or metallic foreign bodies -embarrassing examination for claustrophobic patients Nursing intervention: Assess for any metallic implants, if present the MRI cant be done Remove all jewellery Written consent. In case of gadolinium administration ( contrast product), renal function should be assessed and same preparation as for CT scan should be done Inform the patient about the procedure: -patient should be lying flat on the MRI table. -Communication with the heathcare will be through microphone 8-Fluoroscopic Studies Chest fluoroscopy is an imaging test that uses X-rays to look at how well the lungs are working. It can also look at other parts of the respiratory tract. Fluoroscopy is a kind of X-ray "movie." This test uses more radiation than a standard chest X-ray. o It is may used to study the chest wall movement, mediastinum, heart and diaphragm o To detect diaphragm paralysis o To locate lung mass o To perform fine needle aspiration biopsy 9- Pulmonary angiography o It is used to investigate thromboembolic disease of the lung and congenital abnormalities of pulmonary vascular tree. o Rapid injection of radiopaque agent into vasculature of the lungs o Injection can be inserted in arm or femoral vein or great vessel proximal to pulmonary artery with a catheterized needle Nursing intervention: - Precaution should be taken for patients with history of allergic reaction to iodine. (allergy to shellfish). - Explain procedure to the patient - Explain that when the dye is injected in the vein it may cause a flushing sensation or nausea. - Obtain informed consent. - Patient should be NPO - Kidney function tests should be evaluated before scanning - Encourage the patient to drink fluids after scanning to flush the contrast material from the kidney. - Coagulation profile should be done before and after the examination, for risk of bleed and risk of hematoma. - Monitor site of injection and distal pulses. 10- Lung scans or Radioisotope 10.1 V/Q scan: type of nuclear imaging Two types of v/q scan be performed: perfusion scans and ventilation scans. Pulmonary ventilation (V) and Perfusion (Q) scan, also known as lung V/Q scan, is a nuclear test that uses the perfusion scan to delineate the blood flow distribution and ventilation scan to measure airflow distribution in the lungs The isotope we use most is technetium, because it is readily available, has suitable physical characteristics for imaging, and also has the ability to link readily with other molecules to provide a whole range of radiopharmaceuticals suitable for investigating all the major body systems A perfusion scan is performed to evaluate arterial pulmonary blood flow and to detect pulmonary emboli. A radioactive contrast agent is injected via a peripheral vein in the arm, scanning shows the distribution of blood flow through the lungs. Ventilation lung scan: Is performed after the patient take a deep breath of a mixture of a usually xenon( radioactive agent by nebulizer). And then the airflow distribution in the lungs is measured. A radioisotope, also known as a radioactive isotope, is an atomic variant of an element that emits radiation Need 45 minutes.  Nuclear medicine uses radioactive materials to create images of the body. These materials make radiation. Radiation is a kind of energy. Special machines are able to detect this energy. With this information, they can form an image of the body. Indication: Perfusion Scan: To diagnose pulmonary embolism. Ventilation Scan: To detect poor ventilation such as in emphysema – pneumonia, asthma, carcinoma, and bronchitis. Nursing Intervention : Precaution should be taken for patients with history of allergic reaction to iodine. (allergy to shellfish). Explain procedure to the patient, explain that when the dye is injected in the vein it may cause a flushing sensation or nausea. Obtain informed consent. Encourage the patient to drink fluids to flush the contrast material from the kidney.  Gallium scan: Gallium is injected intravenously and scans are taken to evaluate gallium uptake by pulmonary tissues. It is useful in diagnose abscess, adhesions and tumors. A gallium scan uses gallium citrate. It’s a drug that has very small amounts of radioactive gallium. A day or two before the scan, the healthcare provider injects the gallium citrate into a vein. The gallium then travels all over the body. It builds up in any cells that are actively dividing, such as cancer cells. It also binds to cells and proteins involved in inflammation in the body.  PET scan: Positron emission tomography with advanced diagnostic evaluation for metabolic changes in pulmonary tissues. It is useful to distinguish normal tissues from diseases tissues such as ( malignant nodules) PET imaging PET imaging (positron emission tomography) is a new technique in nuclear medicine. it is having a huge impact in oncology (cancer medicine) due to its ability to detect small areas of active tumour, allowing early treatment. Endoscopic studies 11. Bronchoscopy 12. Thoracoscopy 13. Thoracentesis 11- Bronchoscopy o It allows direct inspection and visualization of the larynx, trachea and bronchi via a bronchoscope. o It can be rigid fiber optic scope to remove foreign objects or thin flexible fiber optic for cytologic examination Types of Bronchoscopy: Rigid bronchoscope: is used to remove foreign objects from larynx or trachea. The fiber optic bronchoscope: is a thin, flexible bronchoscope, because of its small size, its flexibility and its excellent optical system, it allows visualization of the segmental and sub segmental bronchi, cytological examination can be performed. General anesthesia is sometimes used. However, in most cases the patient is sedated and a local anesthetic is sprayed over the mouth, tongue and throat. Lidocaine jelly is used both lubricate the bronchoscope and suppress the gag reflex. The bronchoscope is introduced through the nose or mouth through the trachea and into main stem bronchi. Just before the procedure the patient is given atropine to dry respiratory secretion and a sedative agent.  Contraindications Acute asthmatic episode. Patient not NPO for 6 hours. Hypoxia, unless patient is intubated. Uncooperative patient. Respiratory failure requiring high FIO2 Bleeding diathesis-severe thrombocytopenia or coagulopathy. Indication of Bronchoscopy: a. Diagnosis: To diagnose lung infection, lung tumor To examine tissue or collect secretion (culture for presence of microorganism) , To obtain tissue specimens of the lung in a variety of disorders. Specimens may be taken from inside the lungs by biopsy, bronchoalveolar lavage, or endobronchial brushing. To determine the location and extent of pathologic process. To determine if tumor can be resected surgically To diagnose bleeding site (Hemoptysis). To examine tissue patency To diagnose lung infection or tumor To view abnormalities of the airway. b. Therapeutic Bronchoscopy: Remove foreign bodies Remove secretion Destroy and excise lesion Treat post-operative atelectasis Laser resection of tumors or benign tracheal and bronchial strictures. Bronchoscopy is also employed in Percutaneous tracheostomy. Tracheal intubation of patients with difficult airways is often performed using a flexible bronchoscope Nursing Intervention: Pre procedure The RN will:  Complete the nursing history and assessment including allergies.  Notify the physician if patient is currently on anticoagulation therapy, ASA, or nonsteroidal anti- inflammatory products and if laboratory results are abnormal.  Obtain CXR or CT scan.  Ensure informed consent is obtained.  Obtain baseline vital signs and oximetry. Establish baseline cardiac rhythm as per hospital policy.  Verify length of NPO status, 6-8 hours before the procedure to reduce the risk of aspiration when the cough reflex is blocked by anesthesia.  Remove any dental prosthesis.  Explain procedure to the patient.  Establish patent IV line as ordered.  Explain the use of premedication to be used.  Administer pre medication as ordered: Aerosol mask, Atropine (antichollinergic) to block vagal stimulation inhibit Bradycardia, depress cough reflex, decrease secretion.Valium for muscle relaxant & Dormicum (sedatives)  Oxygen and suction apparatus at bedside Intra procedure The RN will: Assist and support the patient during the procedure. Ensure resuscitation equipment and suction is readily available. Attach the monitoring devices such as ECG leads and pulse oximetry as per institutional policy. Monitor and maintain the patient’s cardiopulmonary status, which may include titrating O2 therapy or maintaining the patient ventilation system when required. Assess color, warmth and dryness of skin. Administer medication as ordered, including aerosol delivery, medication via the bronchoscope or IV medication. Provide and document the minimal monitoring of all patients including BP, pulse, respiration, O2 sat, level of consciousness and pain tolerance. Label all specimens taken with pertinent patient information and site of biopsy. Send specimens to the appropriate laboratory. Post procedure The RN will: Post procedure O2 supplementation may be required in some patients, Particularly those with impaired lung function and those who have been sedated. Assess BP, heart rate, respiratory rate, depth and effort. O2 saturation and level of consciousness on admission to recovery area, after 15 minutes, until stable and at discharge. Post procedure oximetry must be performed until the patient’s respiratory status is stable or returned to pre-procedure state. Keep patient NPO until gag reflex returns. Reassure the patient it is common to have some bleeding after a biopsy is done, however coughing up more than 2 tsp of blood requires that the patient contact the physician. Patient should be kept in semifolwer position Fluids may be given after the gag and swallow reflexes return usually about 2 hours after the procedure Pink tinged secretion after Bronchoscopy are normal but Hemoptysis suggest hemorrhage. The nurse must observe closely for the following: Cyanosis Tachycardia Nursing Alert Hypotension Dyspnea Sedation given to patient with respiratory insufficiency Bronchospasm can lead to respiratory arrest!------- Dysarthmia Complications post Bronchoscopy oReaction to local anesthesia oBleeding oInfection oPerforation oAspiration o Pneumothorax oBronchospasm oHypoxia 12-Thoracoscopy o It is a diagnostic procedure in which the pleural cavity examined with an endoscope o Small incisions are made into pleural cavity in an intercostals space. o fluid present in the pleural cavity is aspirated and the pleural cavity is examined. o After procedure, chest tube may be inserted into the pleural cavity o It is useful to diagnose pleural effusion, pleural disease and tumor staging. o Biopsy of lesions can be performed. Pre procedure The RN will:  Notify the physician if patient is currently on anticoagulation therapy, ASA, or nonsteroidal anti-inflammatory products and if laboratory results are abnormal.  Obtain CXR or CT scan.  Ensure informed consent is obtained.  Obtain baseline vital signs and oximetry. Establish baseline cardiac rhythm as per hospital policy.  Explain procedure to the patient.  Establish patent IV line as ordered.  Explain the use of premedication to be used.  Oxygen apparatus at bedside Intra procedure( same as intra-procedure of bronchoscopy) Post procedure nursing intervention o Monitor patient for shortness of breath( indication of pneumothorax) o Encourage patient to restrict minor activity o Monitor of chest drainage system and chest tube insertion site if applied 13- Thoracentesis A thin layer of pleural fluid normally remains in the pleural space. An accumulation of pleural fluid may occur with some disorders. A sample of this fluid can be obtained by thoracentesis (aspiration of pleural fluid for diagnostic or therapeutic purposes). It is important to position the patient. A needle biopsy of the pleura may be performed at the same time. Studies of pleural fluid include Gram’s stain culture and sensitivity, acid-fast staining and culture, differential cell count, cytology, pH, specific gravity, total protein, and lactic dehydrogenase. A needle is inserted to the pleural cavity to remove air or excess fluid. Intra pleura chemotherapy may be introduced through Thoracentesis also Site of Insertion: Depend on the result, if there is a presence of air on the pleural cavity the site of insertion is in the second intercostals space anteriorly because air rises in the thorax while if there is a fluid in the pleural cavity needle is inserted in the seventh intercostals space posterior. A thoracentesis (aspiration of fluid or air from the pleural space) is performed on patients with various clinical problems. A diagnostic or therapeutic procedure, thoracentesis may be used for: Removal of fluid and air from the pleural cavity Aspiration of pleural fluid for analysis Pleural biopsy Instillation of medication into the pleural space  1- Pulmonary function Tests Pulmonary function tests are performed to assess the presence and severity of disease in the large and small air way. Pulmonary function tests are performed to assess the respiratory function & to determine the extent of dysfunction & response to treatment. Pulmonary function tests are performed by a technician using a spirometry that has a volume collecting device attached to a recorder that records volume and time. A- Lung volume B- Lung capacities  PFTs are useful in monitoring patient’s response to therapy  In screening of industries hazardous  Prior to abdominal & thoracic surgery  Diagnosis of occupational respiratory diseases  Obese patient with high risk pulmonary problem history. Instructions to give for the patient: - Do not Smoke one hour before the test. - Do not drink alcohol 4 hours before the test. - Do not eat a large meal within 2 hours of test. - Wear loose clothing. - Do not perform vigorous exercice within 30 minutes of test. - Look for physician instructions regarding inhaler medication.  2- Blood Gas Studies It is an essential test in diagnose and monitor patient with respiratory disorders and adjusting oxygen therapy. ABG studies aid in assessing the ability of lungs to provide adequate oxygen and remove carbon dioxide. The ability of the kidneys to reabsorb or excrete bicarbonate ions to maintain normal PH of the blood. Patency of lungs or damaging after chest trauma.  Blood gas analysis determines the PH, saturation of oxygen in blood, partial pressure of oxygen and partial pressure of CO 2 and level of HCO3. PH: is an indicator of hydrogen ion (H+) concentration in the blood. N.B: Partial pressure is the pressure exerted by each type of gas in a mixture of gases. Regulation of PH: The body has the ability to maintain plasma PH with normal range of 7.35 to 7.45 it does so by means of: - Chemical buffering mechanisms - By the kidneys - By the lungs  Buffer Systems Bicarbonate – carbonic acid (chemical buffers): Chemical buffers are substances that prevent major changes in the PH of body fluids by removing or releasing hydrogen Ions. The body’s major buffer system is the bicarbonate (HCO3) – carbonic acid (H2CO3) buffer system. Normally: there are 20 parts of bicarbonate to 1 part of carbonic acid, the ratio is 20:1 (alkaline) HCO3 : H2CO3 (acid) When this ratio change so the PH will change also. Procedure for obtaining ABG’s Equipments: -Tray -Kidney basin -Betadine swabs -Plaster -Disposable gloves -Sharp box -heparinzed syringe -Dry gauze Procedure: - Place the patient in comfortable position - Perform Allen’s test to assess collateral circulation prior to performing the radial puncture. - If collateral circulation in the ulnar artery is inadequate, another site should be chosen. - Elevate the wrist with a small pillow and ask the patient to extend the fingers downward. Palpate the artery and rotate the patient’s hand back and forth until a good strong pulse is felt. - Swab the area with antiseptic agent such as Betadine. - If the syringe is not prepared, aspirate 1 ml than insert the needle 450 , blood draw into syringe without aspiration. - Withdraw the needle and place dry gauze over the puncture site and maintain pressure with two fingers for a minimum of 2 minutes. (if patient takes anticoagulant press more time) - Place the sample on ice and remove to the laboratory. This will prevent alterations in gas tensions because metabolic process continue after blood is drawn. Examples: PaO2 = 89 SaO2 = 93 PH = 7.51 PaCO2 = 41 HCO3 = 30  non compensatory metabolic alkalosis. PaO2 = 63 SaO2 = 86 PH = 7.31 PaCO2 = 51 HCO3 = 24  non compensatory respiratory acidosis. PaO2 = 95 SaO2 = 96 PH = 7.36 PaCO2 = 29 HCO3 = 18  complete compensated metabolic acidosis. PH = 7.34 PaCO2 = 43 HCO3 = 18  non – compensatory metabolic acidosis PH = 7.48 PaCO2 = 25 HCO3 = 34  mixed metabolic & respiratory alkalosis. PH = 7.49 PaCO2 = 31 HCO3 = 20  partially – compensated respiratory alkalosis. 14- Biopsy  Biopsy, the excision of a small amount of tissue, may be performed:  To permit examination of cells from the pharynx, larynx, and nasal passages.  Local, topical, or general anesthesia may be administered, depending on the site and the procedure  Biopsy may be done to assess Pleural tissue, lung tissue or lymphnodes Nursing interventions After the procedure, recovery and home care are similar to those for bronchoscopy and thoracoscopy.  Nursing care involves: Monitoring the patient for shortness of breath, bleeding, and infection. In preparation for discharge, the patient and/or family is instructed to report pain, shortness of breath, visible bleeding, or redness of the biopsy site or pus to the health care provider immediately. Patients who have undergone biopsy are often anxious because of the need for the biopsy and the potential findings The nurse must consider this in providing peri-biopsy care and teaching. THANK YOU FOR YOUR ATTENTION