Respiratory System Diagnostic Procedures PDF

RESPIRATORY SYSTEM PAB RN MAN ALLCC RN MD  Diagnostic Studies  1. ABG monitoring An arterial blood gas test measures the amounts of arterial gases, such as oxygen and carbon dioxide. An ABG test requires that a small volume of blood be drawn from the radial artery with a...

RESPIRATORY SYSTEM PAB RN MAN ALLCC RN MD  Diagnostic Studies  1. ABG monitoring An arterial blood gas test measures the amounts of arterial gases, such as oxygen and carbon dioxide. An ABG test requires that a small volume of blood be drawn from the radial artery with a syringe and a thin needle, but sometimes the femoral artery in the groin or another site is used. The blood can also be drawn from an arterial catheter. Components of ABG pH (7.35-7.45) – measurement of the hydrogen ion concentration (reflects blood acidity or alkalinity PaCO2 (35-45 mmHg) - partial pressure of arterial CO2 (reflects adequacy of ventilation of the lungs) PaO2 (80-100 mmHg) – reflects the body’s ability to pick up O2 from the lungs HCO3 ( 22-26 mEq/L)- bicarbonate level reflects the activity of the kidneys in retaining or excreting bicarbonate SaO2 ( 95-100%) – the ratio of the actual Hgb O2 content to potential maximum oxygen carrying capacity of Hgb. Diagnostic Studies  Interpreting ABG values  PaO2 – value greater than 100 mmHg reflects more than adequate supplemental oxygen administration. A value less than 80 mmHg indicates hypoxemia  SaO2 – value less than 95% represents decreased saturation and may contribute to a low PaO2 value  pH – value above 7.45 (alkalosis) reflects a H+ deficit  a value below 7.35 (acidosis) reflects H+ excess  Nursing considerations  In most critical care units, a doctor respiratory therapist, or a specially trained critical care nurse draws ABG samples usually from arterial line if the patient has one.  If percutaneous puncture must be done the site must be chosen carefully.  1. Radial artery – most common site. Allen’s test is done before withdrawing the sample  2. brachial artery  3. femoral artery  Diagnostic Studies  Nursing considerations  After obtaining the sample, apply pressure to the puncture site for 5min and tape a gauze pad firmly in place. Monitor the site regularly for bleeding, check the arm for signs of complication( swelling, discoloration, pain, numbness, and tingling)  Note whether the patient is breathing room air or oxygen. If the patient is on oxygen via nasal canula indicate the number of liters.  If the patient is receiving oxygen by mask or mechanical ventilation indicate the fraction of inspired oxygen (FIO2).conditions that can interfere with the test results are failure to heparinize the syringe before drawing the blood sample, exposing the sample to air,  Venous blood in the sample may lower PaO2 levels and elevate PaCO2  Make sure arterial blood sample is kept cold preferably on ice and delivered as soon as possible to the lab. for analysis.  Obtaining ABG Sample  1. Prepare a heparinized blood gas syringe to draw the sample  2. After preforming Allen’s test, perform a cutaneous arterial puncture aseptically. (if an arterial line is in place draw blood from arterial line)  3. eliminate air from the sample, place it on ice immediately, and transport it for analysis  Apply pressure to the puncture site for 3-5min. If the patient is receiving anticoagulants or has coagulopathy, hold the puncture site longer than 5min. if necessary  Tape a gauze pad firmly over the puncture site. If the puncture site is on the arm, don’t tape the entire circumference, this may restrict the circulation  Pulmonary Angiography  Pulmonary angiography ( pulmonary arteriography) allows radiographic examination of the pulmonary circulation.  After injecting a radioactive contrast dye through a catheter inserted into the pulmonary artery a series of X-ray is taken to detect blood flow abnormalities, possibly caused by emboli or pulmonary infarction  PA is more reliable and preferred than V/Q scanning esp. if the patient is on ventilator but carries higher risk for cardiac arrythmias  Nursing considerations:  Explain the procedure to the patient and his family, answer their questions  Tell them who performs the test, where it is done and how long it takes.  Preprocedure Patient preparation:  Confirm the patient is not allergic to shellfish or Iodine. Notify the practitioner if pt. has allergy Pulmonary Angiography  Preprocedure Patient Care:  Evaluate: -the renal function (BUN, Creatinine level) -Potential risk of bleeding (PT, PTT and platelet count)  Instruct the patient to lie still for the procedure  Explain that he’ll probably feel a flushed sensation in his face as the dye is injected  Postprocedure Patient Care:  Maintain bed rest as ordered, monitor the V/S, O2 sat. levels and heart rhythm  Keep a sandbag or femoral compression device over the injection site as ordered  Check the pressure dressing for signs of bleeding, monitor the peripheral pulse in the arm or leg used for catheter insertion. (mark the site), check the temp., color and sensation of the extremity and compare with the opposite side  Pulmonary Angiography  Postprocedure Patient Care  Unless contraindicated, encourage the patient to drink more fluids to flush the dye or contrast medium from his system, or increase the IV flow rate as ordered.  Check the serum, BUN, Creatinine levels after the procedure  Monitor for adverse reactions to contrast medium (restlessness, tachypnea, respiratory distress, tachycardia, facial flushing, urticaria, nausea and vomiting  Keep emergency equipment nearby in case of a reaction  Ventilation-Perfusion Scan  A V/Q scan is used to:  evaluate V/Q mismatch  detect pulmonary emboli  evaluate pulmonary function, especially in patients with marginal lung reserves.  carries fewer risk but less reliable than pulmonary angiography  2 parts of V/Q scan  1. during the ventilation portion of the test – the patient inhales the contrast medium gas, ventilation patterns and adequacy of ventilation are noted on the scan  2. during the perfusion scan, the contrast medium is injected I.V. and the pulmonary blood flow to the lungs is visualized. Ventilation-Perfusion Scan  Nursing considerations:  Explain the procedure to the patient and his family, Tell them who performs the test, where it is done  Confirm that the patient doesn’t have an allergy to the contrast material.  Explain to the patient that the test has two parts.  1. During the ventilation portion , a mask is placed over his mouth and nose and the patient breathes in the contrast medium gas mixed with air while the scanner takes pictures of his lungs  2. during the perfusion portion , the patient is placed in a supine position on a movable table as the contrast medium is injected into the I.V. line while the scanner again takes pictures of the lungs  After the procedure, maintain bed rest as ordered, monitor the patient’s V/S, O2 sat. levels and heart rhythm  Monitor for adverse reactions to contrast medium (restlessness, tachypnea, respiratory distress, tachycardia, facial flushing, urticaria, nausea and vomiting  Keep emergency equipment nearby in case of a reaction Capnography  Capnometry – is a continuous, noninvasive method for evaluating the adequacy of CO 2 exchange in the lungs  Capnography - is the monitoring of the concentration or partial pressure of carbon dioxide (CO₂) in the respiratory gases.  Its main development has been as a monitoring tool for use during anesthesia and intensive care. It is usually presented as a graph of expiratory CO₂ (measured in millimeters of mercury, "mmHg") plotted against time, or, less commonly, but more usefully, expired volume.  Capnography can rapidly and accurately alert clinicians to perfusion and/or metabolic problems and provide deeper insight than traditional assessment tools.  The Greeks first believed that the body had a central combustion center and that this system had a by-product. They named this by-product capnos, which is Greek for “smoke.”   Today, we call this combustion center “metabolism”  and capnos “carbon dioxide”  (CO 2).  Capnography  Indications :  - useful in mechanically ventilated patient who requires frequent blood gas sampling  - patient who has an unstable respiratory status in which minute-to-minute assessment of gas exchange is necessary  Recommended for use in confirming endotracheal tube placement  For assessment of patient response to different modes of ventilation and tolerance to weaning  Device Set-up - Capnometer for Breathing (https://youtu.be/NCTYUZwoCCs) Pleural Fluid Analysis THANK YOU