RESPIRATORY-SYSTEM-NCM-411.pptx_20240910_231607_0000.pdf

RESPIRATORY SYSTEM  SPECIAL ASSESSMENT TECHNIQUES, DIAGNOSTIC TESTS, AND MONITORING  CHEST X-RAY Chest radiography is an important tool in respiratory assessment because it provides visualization of the heart and lungs  they are obtained as part of the routine screening when: Respira...

RESPIRATORY SYSTEM  SPECIAL ASSESSMENT TECHNIQUES, DIAGNOSTIC TESTS, AND MONITORING  CHEST X-RAY Chest radiography is an important tool in respiratory assessment because it provides visualization of the heart and lungs  they are obtained as part of the routine screening when: Respiratory disease is suspected to evaluate the status of respiratory abnormalities (e.g pneumothorax, pleural effusion, tumors) to confirm proper invasive tube placement (ex. ET, tracheostomy tube) traumatic chest injury  BASIC CONCEPTS ABOUT X-RAY a normal lung looks black on chest films because lungs are primarily sacs of air or gas the skeletal thorax appears white because bone is very dense and absorbs most of the x-rays heart and mediastinum appear gray because they are made up mostly of water breast tissue is made up of mostly fat and it appears whitish gray  BASIC VIEW OF THE CHEST the most common method of obtaining a chest x-rays is the Posterior-anterior (PA) view. lateral view – to identify normal and abnormal structures behind the heart and the base of the lung  lordotic view – to better visualize the apical and middle portions of the lungs lateral decubitus - patient is supine or side lying  SYSTEMATIC APPROACH TO CXR INTERPRETATION Begin the chest x-ray analysis by comparing the right side to the left side 1. soft tissues – neck, shoulders, breasts and subcutaneous fat 2. trachea – the column of radiolucency readily visible above the clavicles 3. bony thorax – note the size, shape and symmetry 4. intercostal space – note the width and angle 5. diaphragm – dome shaped with distinct margin, right dome 1 to 3 cm higher than left dome. 6. pleural surfaces – visceral and parietal pleura appear like a thin hair line along the apices and lateral chest 7. mediastinum – size varies with age, gender and size 8. hila – large pulmonary arteries and veins 9. lung field – largest area of the chest 10. catheters, tubes, wires and line NORMAL CHEST X- RAY  BASIC X-RAY DENSITIES Radioluscent (black) gas, air – dark or black ( lungs, trachea, bronchi, alveoli water – dark or gray (heart, muscle, blood, blood vessels, diaphragm, spleen, liver fat – lighter or whitish gray (breast, marrow, hilar streaking) Radiopaque (white) metal, bone – (lighter or white) ribs, scapulae, vertebrae, bullets, coins, teeth, ECG electrodes Normal Variants & Common Abnormalities the most common cause of tracheal deviation is pneumothorax, which causes a tracheal and mediastinal shift to the area away from the pneumothorax Clavicles should be symmetric – decrease in density (less white) of the spine, rib and other bones may indicate loss of calcium from the bone due to osteoporosis.  Patient with COPD have widened intercostal space and the angle of the ribs because of severe hyperinflation narrowed ICS may be visible with rib fracture WIDENED ICS  elevation of the diaphragm can be a result of an abdominal distention or lung collapse depression can occur when 11 and 12 ribs show COPD blunting of the costophrenic angle can occur with pleural effusion or atelectasis  a widening of the mediastinum can indicate cardiomegaly, aneurysm bleeding into the mediastinum following chest trauma or cardiac surgery can also cause WIDENING MEDIASTI NUM density increases when water, pus, or blood accumulates in the lungs in Pneumonia increased radiolucency is caused by increased air in the lungs as may occur with COPD COMPUTED TOMOGRAPHY AND MRI more advantageous over CXR to evaluate the mediastinal and pleural abnormalities particularly those with fluid collection Pulmonary Angiograms one of the most sensitive tools for diagnosis of pulmonary emboli through a catheter advanced into the pulmonary artery, contrast material is injected during the rapid filming Emboli appear as dark circumscribed areas Pulmonary angiography is an X-ray procedure that looks at the blood vessels leading to and from your lungs. The X-rays produced are called pulmonary angiograms, which may show blood clots in and around your lungs — called pulmonary embolisms A special dye stains your blood vessels, so they appear bright white under X-rays. This contrast allows doctors to see any blood clots and other blood vessel- related conditions. Pulmonary angiography is often used to look for blood clots in the artery that leads from your heart to your lungs. Chest Tubes are used in critically ill patients to drain air, blood, fluid from the pleural space or mediastinum pleural tube insertion are based on the type of drainage to be removed they are placed during surgery following surgery chest tubes are connected to a closed drainage collection system following surgery chest tubes are connected to a closed drainage collection system which uses gravity or suction to restore negative pressure in the pleural space and to facilitate drainage of fluids or air  AIR EMBOLISM A venous air embolism occurs when air enters the venous system and eventually causes an obstruction in the pulmonary circulation When there is clinical suspicion of air embolism, a number of initial steps should be taken quickly to manage the situation. The initial priority is to prevent further air embolism; if air is noted entering the arterial system, the flush should be stopped immediately and the rotating hemostatic valve (RHV) should be fully opened. The arterial pressure should be allowed to passively push the air back out. In the case of an unresponsive patient, the first priority is to address airway, breathing and circulation (ABC), including cardiopulmonary resuscitation (CPR) when necessary. What is a central venous catheter? A central venous catheter, also called a central line or CVC, is a device that helps you receive treatments for various medical conditions. It’s made of a long, thin, flexible tube that enters your body through a vein. The tube travels through one or more veins until the tip reaches the large vein that empties into your heart (vena cava). ACUTE RESPIRATORY FAILURE the origin of respiratory failure may be medical or surgical problem it is a change in respiratory gas exchange (CO2 and O2) such that normal cellular function is jeopardized ARF is defined as PaO2 less than 60 mmHg and PaCO2 greater than 50 mmHg with a pH less than or equal to 7.30 factors that affects include: age, altitude, chronic cardiopulmonary disease  many abnormalities can lead to ARF regardless of the underlying cause the pathophysiology of ARF can be organized into four main components: impaired ventilation impaired gas exchange airway obstruction ventilation-perfusion abnormalities  IMPAIRED VENTILATION conditions that disrupt the muscles of respiration of their neurologic control can impair ventilation and lead to ARF. Spinal cord injury neuromuscular blockade Guillain –barre syndrome increased ICP decreased or absent respiratory muscle movement may be due to fatigue from excessive use, atrophy from disuse, inflammation of nerves, nerve damage( ex. Surgical damage to the vagus nerve during cardiac surgery) progressive disease states such as Guillian Barre Syndrome Impaired respiratory muscle movement decrease movement of gases into lungs, resulting in alveolar hypoventilation inadequate alveolar ventilation causes retention of CO2 and hypoxemia  IMPAIRED GAS EXCHANGE Conditions that damage the alveolar capillary membrane impair gas exchange (ARDS) direct damage to the cells lining the alveoli may be caused by inhalation of toxic substances (gases and gastric contents) leading to 2 detrimental alveolar changes  1. an increase in alveolar permeability, increasing the potential for interstitial fluid to leak into the alveoli and cause noncardiac pulmonary edema. 2. alveolar change is a decrease in surfactant production by alveolar type II cells, increasing alveolar surface tension, which leads to alveolar collapse  another cause of impaired gas exchange occurs when fluid leaks from the intravascular space into the pulmonary interstitial space. the excess fluid increases the distance between the alveolus and the capillary, decreasing the efficiency of the gas exchange process  interstitial edema also compresses the bronchial airways, which are surrounded by interstitial tissue causing vasoconstriction capillary leakage may occur when pressures within the cardiovascular system are excessively high (e.g. heart failure) or when pathologic condition elsewhere in the body release biochemical substances (serotonin, endotoxin) that increase capillary permeability.  AIRWAY OBSTRUCTION Conditions that obstruct airways increase resistance to airflow into the lungs, causing alveolar hypoventilation and decreased gas exchange. Airway obstruction can be due to conditions that: (1) block the inner airway lumen (e.g. excessive secretions or fluid in the airways, inhaled foreign bodies)  (2) increase airway wall thickness (e. g. edema or fibrosis) or decrease airway circumference (e.g. Bronchoconstriction) as occur in asthma (3) increase peribronchial compression of the airway (e.g. enlarged lymph nodes, interstitial edema, tumors)  VENTILATION-PERFUSION ABNORMALITIES Conditions disrupting alveolar ventilation or capillary perfusion lead to an imbalance in ventilation and perfusion in an effort to keep the ventilation and perfusion ratios balanced, two compensatory changes can occur:  (1) to avoid wasted alveolar ventilation when capillary perfusion is decreased (e.g. pulmonary embolism) bronchiolar constriction occurs to limit ventilation to alveoli with poor or absent capillary perfusion  (2) to avoid capillary perfusion of alveoli that are not adequately ventilated (e.g. with atelectasis), arteriole constriction occurs and shunts blood away from hypoventilated alveoli to normally ventilated alveoli as the number of alveolar capillary units affected by these compensatory changes, increases, gas exchange eventually is affected negatively  Clinical Presentation/S/Sx hypoxemia (PaO2 ˂60 mmHg) low level of O2 restlessness -impairment of gas exchange between the lungs and the blood causing hypoxia with - tachypnea dyspnea tachycardia confusion diaphoresis anxiety hypercarbia hypertension irritability somnolence (late) cyanosis (late) loss of consciousness (late) pallor or cyanosis of skin use of accessory muscle of respiration abnormal breath sounds (crackles, wheeze) manifestation of primary disease  Diagnostic Tests Arterial Blood Gases – PaO2 less than 60 mmHg and PaCO2 more than 50 mmHg: with pH less than or equal to 7.30 or PaO2 and PaCO2 in abnormal range for that individual  Principles of Management for ARF: 1. Improving oxygenation and ventilation a.)provide supplemental O2 to maintain PaO2 greater than 60 mmHg, use of nasal cannula or face mask is preferable if acceptable PaO2 levels can be achieved. b.) improve ventilation with the administration of bronchodilators, mucolytic agents and other airway mgt modalities (chest physiotherapy, suctioning, positioning)  intubate and initiate mechanical ventilation if non invasive methods fail to correct hypoxemia during suctioning , closely observe for signs and symptoms of complications (respiratory distress, cardiac arrythmias – hyperoxygenate with 100% oxygen using manual resuscitation bag  2. Reducing Anxiety maintain a calm , supportive environment to avoid unnecessary escalation of anxiety give brief explanation of activities and approaches being done to relieve ARF teach diaphragmatic breathing to slow the rate and increase the depth of respirations. Place one hand on the patients abdomen administer mild doses of anxiolytics  3. Preventing and Managing Complications Pulmonary aspiration – ensure proper inflation of endotracheal tube cuff at all times Gastrointestinal bleeding – check gastric aspirate for presence of occult blood every 4 to 8 hours Barotrauma – avoid unnecessary increase in airway pressures(ex. Excessive coughing) and asses for signs of pneumothorax