Bill Davies PAC RRT. Dyspnea: Uncovering Restrictive lung Disorders in Your Setting

Transcription

1 Bill Davies PAC RRT Dyspnea: Uncovering Restrictive lung Disorders in Your Setting

2 Bill Davies PAC RRT Confluence Health Division of Pulmonary/ Sleep Disorders

3 Conversation Topic Brief Review of Dyspnea Explain the considerations associated with clinical presentation, evaluation and imaging in terms of differentially diagnosing RLD Importance of PCP Role in Today s Settings

4 The Temporal Lobe mainly revolves around hearing and selective listening. It receives sensory information such as sounds and speech from the ears. It is also key to being able to comprehend, or understand meaningful speech. This lobe is special because it makes sense of the all the different sounds and pitches (different types of sound) being transmitted from the sensory receptors of the ears.

5 Ready

6 Engage

7 Dyspnea Dyspnea is likely from: complex interactions between: chemoreceptor stimulation mechanical abnormalities in breathing perception of those abnormalities by CNS

8 DESCRIPTORS FOR AIR HUNGER COMMONLY CHOSEN Urge to breathe Unsatisfied inspiration Like breath hold Feeling of suffocation Starved for air Hunger for air Breaths felt too small Need for more air Breath does not go in all the way Cannot get enough air

9 AFFERENT SOURCES FOR RESPIRATORY SENSATION Source of Sensation Medullary respiratory corollary discharge Primary motor cortex corollary discharge Limbic motor corollary discharge Carotid and aortic bodies Medullary chemoreceptors Slowly adapting pulmonary stretch receptors Adequate Stimulus Drives to automatic breathing (hypercapnia, hypoxia, exercise) Voluntary respiratory drive Emotions Hypercapnia, hypoxemia, acidosis Hypercapnia Lung inflation Rapidly adapting pulmonary stretch receptors Airway collapse, irritant substances, large fast (sudden) lung inflations/deflations Pulmonary C-fibers (J-receptors) Airway C-fibers Upper airway flow receptors Muscle spindles in respiratory pump muscles Tendon organs in respiratory pump muscles Metaboreceptors in respiratory pump muscles Vascular receptors (heart and lung) Trigeminal skin receptors Chest wall joint and skin receptors Pulmonary vascular congestion Irritant substances Cooling of airway mucosa Muscle length change with breathing motion Muscle active force with breathing motion Metabolic activity of respiratory pump Distention of vascular structures Facial skin cooling Tidal breathing motion

10 Innervation of Airway

11 CAUSES OF DYSPNEA GROUPED BY PHYSIOLOGICAL MECHANISM Increased respiratory drive increased afferent input to respiratory centers Stimulation of pulmonary receptors (irritant, mechanical, vascular) Interstitial lung disease Pleural effusion (compressive atelectasis) Pulmonary vascular disease (thromboembolism, idiopathic pulmonary hypertension) Congestive heart failure Simulation of chemoreceptors Conditions leading to acute hypoxemia, hypercapnia, and/or acidemia Impaired gas exchange, e.g., asthma, pulmonary embolism, pneumonia, heart failure

12 MORE CAUSES BY PHYSIOLOGICAL MECHANISM Conditions leading to increased dead space and/or acute hypercapnia Impaired gas exchange, acute, severe asthma, exacerbations of COPD, severe pulmonary edema Impaired ventilatory pump e.g., muscle weakness, airflow obstruction Metabolic acidosis Renal disease (renal failure, renal tubular acidosis) Decreased oxygen carrying capacity, e.g., anemia

13 More Causes of Dyspnea Decreased release of oxygen to tissues, e.g., hemoglobinopathy Decreased cardiac output: Pregnancy Impaired ventilatory mechanics reduced afferent feedback for a given efferent output Airflow obstruction (includes increased resistive load from narrowing of airways and increased elastic load from hyperinflation) Asthma, COPD, laryngospasm, aspiration of foreign body, bronchitis Muscle weakness: Myasthenia gravis, Guillain-Barre, spinal cord injury, myopathy, post-poliomyelitis syndrome Decreased compliance of the chest wall Severe kyphoscoliosis, obesity, pleural effusion

14 With a List of so many Possibles: it is Hard to Pick the Right 1

15 Uncovering This thing called Dyspnea An imbalance between neurologic stimulation and mechanical changes in lung and chest wall A Neuromechanical Uncoupling Work of Breathing Altered Title Volume Neuroplasticy Requires: History, Exams, Knowledge and Testing (?PFT)

16 Lung Volumnes, ERV = expiratory reserve volume; FRC = functional residual capacity; IC = inspiratory capacity; IRV =inspiratory reserve volume; RV = residual volume; TLC = total lung capacity; VC = vital capacity; VT= tidal volume. FRC = RV + ERV; IC =VT + IRV; VC =VT+ IRV + ERV.

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18 Diffusing Capacity in the Face of Dyspnea or Clinical Impressions Carbon Monoxide (DLCO) reduced in all patients with intrinsic lung disorders (severity of the reduction does not correlate well with the stage of the disease). DLCO most sensitive parameter, may be abnormal even when the lung volumes are preserved. Normal DLCO value excludes intrinsic lung disease and indicates a chest wall, pleural, or neuromuscular cause of restrictive lung disease

19 Diffusion Impairments A decreased area for diffusion from emphysema & multiple pulmonary emboli An increase in the thickness of the alveolar-capillary membrane (interstitial lung diseases, asbestosis, congestive heart failure, etc) False diffusion impairment back pressure from recent smoking

20 Other Test Options Arterial blood gas values at rest may reveal hypoxemia and or hypercarbia. Walk Test (timed or not) with oximetry Cardiopulmonary exercise testing with measurements of gas exchange and oxygenation is more sensitive (?)

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22 Causes of Restrictive Lung Disease (RLD) Pleural disease Extrinsic disorders Intrinsic lung diseases Idiopathic Systemic diseases (connective tissue disorders) Toxic, radiologic, environmental, occupational exposures

23 Pleural Disorders Associated with decreased tactile fremitus, dullness upon percussion, and decreased intensity of breath sounds. trapped lung, Hemothroax, CABG, malignancy asbestos related pleural plaques Both under recognized, and potentially treatable

24 Extrinsic disorders Nonmuscular diseases of the chest wall: kyphosis idiopathic or secondary. (The most common cause of secondary kyphoscoliosis is neuromuscular disease (eg, polio, muscular dystrophy). Fibrothorax, massive pleural effusion, morbid obesity, ankylosing spondylitis, and thoracoplasty Neuromuscular diseases : respiratory muscle weakness due to myopathy or myositis, quadriplegia, or phrenic neuropathy from infectious or metabolic causes. Exam shows : accessory muscles usage rapid shallow breathing» paradoxical breathing

25 Tests for Extrinsic lung Lisorders Nonmuscular Diseases of the chest wall PFT :TLC reduced, Stable RV, VC reduced, RV-to-TLC ratio elevated. Inspiratory muscle weakness: Maximal inspiratory (MIP) ventilation and expiratory pressures(mep) cough. Severely reduced with advanced diseases. Hypoxemia due to ventilation-perfusion mismatch by the underlying atelectasis and or shunt. VQ Scan

26 Tests for Extrinsic Lung Disorders In Neuromuscular Diseases, MIP and MEP vary from normal to severely reduced pending decline. MIP below 30 cm, ventilatory failure commonly ensues. Chronic muscular diseases decreased VC and FRC, RV is preserved. TLC moderately reduced. Obesity + OSA: Nocturnal desaturation during rapid eye movement sleep, secondary to hypoventilation. PSG, Oximetry, AM ABG

27 Interstitial Lung Diseases Diverse group of disorders that involve the distal pulmonary parenchyma Typical presentation Progressive dyspnea and dry cough Abnormal pulmonary physiology Abnormal CXR and/or HRCT Etiology Systemic diseases (connective tissue disorders) Toxic, radiologic, environmental, occupational exposures Idiopathic

28 Causes of intrinsic Lung Disease Collagen-Vascular diseases: scleroderma, polymyositis, dermatomyositis, systemic lupus erythematosus, rheumatoid arthritis, and ankylosing spondylitis,. Drugs and other treatments (eg, nitrofurantoin, amiodarone, gold, phenytoin [Dilantin], bleomycin, bischloroethylnitrosourea [BCNU or carmustine], cyclophosphamide, methotrexate, radiation). Also may include sarcoidosis, pulmonary Langerhans cell histiocytosis, LAM, pulmonary vasculitis, alveolar proteinosis, eosinophilic pneumonia. Inorganic dust exposure (eg, silicosis, asbestosis, talc, pneumoconiosis, berylliosis, hard metal fibrosis, coal worker's pneumoconiosis) Organic dust exposure (eg, farmer's lung, bird fancier's lung, bagassosis, and mushroom worker's lung, which all cause hypersensitivity pneumonitis)

29 Idiopathic fibrotic disorders include Acute interstitial pneumonia, Idiopathic pulmonary fibrosis (IPF, usually interstitial pneumonitis UIP), Lymphocytic interstitial pneumonitis, Desquamative interstitial pneumonitis DIP Nonspecific interstitial pneumonitis.

30 Interstitial Lung Diseases ILD of Known Cause or Association Idiopathic Interstitial Pneumonias Sarcoidosis & Other Granulomatous Diseases Other Medications LAM Radiation Pulmonary LCH Connective Tissue Disease Eosinophilic Pneumonias Vasculitis & DAH Alveolar Proteinosis Hypersensitivity Pneumonitis Genetic Syndromes Pneumoconioses

31 Similarities ILD Features Differences Dyspnea Progressive Exertional Cough Non-productive Bibasilar crackles Restrictive ventilatory defect Exertional desaturation ILD on HRCT Prior/current exposures Extrapulmonary findings Sarcoidosis Connective tissue disease Joint involvement Serologies HRCT Honeycombing Ground glass Distribution of abnormalities Histopathology

32 Extrapulmonary Findings (Extra CLUE cards) erythema nodosum, suggest sarcoidosis. Peripheral lymphadenopathy, salivary gland enlargement, and hepatosplenomegaly? signs of systemic sarcoidosis. Uveitis? with sarcoidosis and ankylosing spondylitis A maculopapular rash? connective-tissue diseases, or it may be drug-induced. Raynaud phenomenon? connective-tissue diseases, and telangiectasia present in those with scleroderma.. Cor pulmonale? in the late stages of pulmonary fibrosis or advanced kyphoscoliosis. Loud P2, right-sided precordial lift, and right-sided gallop Pulmonary hypertension and cor pulmonale

33 Approximately 1/2 of the patients with idiopathic pulmonary fibrosis develop clubbing. Clubbing is commonly seen in patients with asbestosis. Other disorders associated with clubbing include cystic fibrosis, pulmonary arteriovenous malformations, cyanotic heart disease, malignancies of the lung and pleura, and inflammatory bowel disease

34 When Should I Suspect ILD? One from Column A and one from Column B Column A Column A Column A Exertional Dyspnea Non-productive Cough Family History of ILD Column B Abnormal CXR Crackles Exertional Desaturation Spirometry (low FVC) or low DL CO

35 Idiopathic Pulmonary Fibrosis Clinical impact Exertional dyspnea Cough Functional and exercise limitation Impaired quality-of-life Risk for acute respiratory failure and death Median survival time of 3-5 years Predominant pathological findings in IPF are fibroblast foci, collagen deposition, and minimal inflammatory cell infiltration Raising the possibility that antifibrotic agents might slow the rate of disease progression

36 Idiopathic fibrotic disorders include Acute interstitial pneumonia, Idiopathic pulmonary fibrosis (IPF, usually interstitial pneumonitis UIP), Lymphocytic interstitial pneumonitis, Desquamative interstitial pneumonitis, DIP Nonspecific interstitial pneumonitis.

37 High resolution computed tomography (HRCT), when typical, demonstrates a characteristic pattern of peripheral (subpleural), bibasilar reticular opacities associated with architectural distortion, including honeycomb changes and traction bronchiectasis Normal Lungs Usual Interstitial Pneumonia

38 Incidence of IPF Risk factors for higher incidence Age Male sex Hispanic ethnic origin Geography

39 Medical care Treatment depends on the specific diagnosis Based on findings from the clinical evaluation, imaging studies, and lung biopsy. Corticosteroids, immunosuppressive agents, and cytotoxic agents once mainstay of therapy are no long (maybe in exacerbation) They Make the Pt and us feel good

40 Ancillary therapies : Supplemental oxygen therapy Pulmonary Rehab helps alleviate : Exercise-induced hypoxemia Anxiety Depression Improve Functional Capacity & Performance Quality of Life

41 Add Procedures Bronchoalveolar lavage In selected cases, bronchoalveolar lavage (BAL) cellular analysis may be helpful to narrow the differential diagnosis. Can provide information that may help lead to a specific diagnosis, help assess for disease activity, exclude neoplastic and infectious processes, establish a definitive diagnosis, and predict the prognosis Surgical lung biopsy Video-assisted thoracoscopic lung biopsy is the preferred method if needed Transplant?

42 Drug Treatment Options for IPF Like other Options in Politics Some ineffective Some incompetent Some with side effects and Risks

43 Maybe Two to Pick From (or not)

44 MEDICAL THERAPIES No medication has been found to cure IPF Two new drugs approved by the FDA in October 2014 Nintedanib (Ofev) Pirfenidone (Esbriet) Patients with mild or moderate IPF based on PFT, who do not have underlying liver disease either pirfenidone or nintedanib are recommend initiating therapy with the available agent

45 MEDICAL THERAPIES Nintedanib: a receptor blocker for multiple tyrosine kinases that mediate elaboration of fibrogenic growth factors (eg, platelet-derived growth factor, vascular endothelial growth factor, fibroblast growth factor), appears to slow the rate of disease progression in IPF. Pirfenidone :is an antifibrotic agent that inhibits transforming growth factor beta (TGF-b)-stimulated collagen synthesis, decreases the extracellular matrix, and blocks fibroblast proliferation in vitro.

46 ACUTE EXACERBATIONS Look for these when Pts decline: infections, pulmonary embolism, pneumothorax, or heart failure. Could just be rapid decline Acute viral infection is unlikely etiology. Lung biopsies performed during an episode, have found background of usual interstitial pneumonia (UIP). NOT done in prime time

47 ACUTE EXACERBATIONS After excluding other causes of worsening dyspnea and hypoxemia: typically treat an acute exacerbation with broad-spectrum antibiotics and high dose glucocorticoids (eg, prednisone 1 mg/kg per day orally or methylprednisolone 1 to 2 g per day intravenously), although scientific evidence for this is lacking Steroids: The Feel GOOD Thing: FOR Them and US Mechanical ventilation carries a high mortality rate

48 RLD Prognosis The natural history of interstitial lung diseases is variable. IPF relentless progressive disorder, mean survival of 3-6 years after diagnosis Early recognition important for directing patient management and predicting prognosis

49 RLD Prognosis Pulmonary sarcoidosis: relatively benign self-limiting course, spontaneous recovery or stabilization in most cases. Approximately 15% of patients develop pulmonary fibrosis and disability. For collagen-vascular diseases, Eosinophilic pneumonia, and drug-induced lung disease is generally favorable with treatment. Pt with chest wall diseases and neuromuscular disorders develop progressive respiratory failure and succumb during an undercurrent pulmonary infection

50 Alter Life style: Disease Modifying Pulmonary Rehab Pulmonary Rehab Pulmonary Rehab Pulmonary Rehab

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52 The mnemonic "PAINT" has been used to divide the causes of restrictive lung disease into pleural, alveolar, interstitial, neuromuscular, and thoracic cage abnormalities. Causes Examples Diagnosis PFT Findings Pleural Trapped lung, pleural scarring, large pleural effusions, chronic empyema, asbestosis Radiography, CT scanning, pleural manometry, pleural biopsy Low RV, low TLC, low FVC Alveolar Edema, hemorrhage Radiography, CT scanning, physical examination Increased DLCO in hemorrhage Interstitial Interstitial lung disease including IPF, NSIP, COP Radiography, CT scanning, physical examination, echo often shows pulmonary hypertension Low RV, low FVC, low TLC, decreased DLCO, poor lung compliance Neuromuscular Myasthenia gravis, ALS, myopathy Physical examination, EMGs, serology Low RV, low TLC, low NIF, low MMV Thoracic/extrathoracic Obesity, kyphoscoliosis, ascites Physical examination Low ERV and FRC in obesity, low VC, TLC, FRC in kyphoscoliosis

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54 Three Take Home Points, One Do I see a reason for dyspnea like history of surgery, smoking, exposure,?

55 Take Home Point Two You need to think?: Do a simple walk test with patient in hall to eval breathing, HR and oxygenation, DOE Full PFT turns on lights Does exam suggest COPD or RLD and would CT tease out a DX Referral is always OK

56 Take Home Point Three? Why we entered Healthcare. 1. Seeking Satisfaction and Competency 2. Have Technical Skills, 3. Capable to Solve the Question 4. Intellect to Treat Difficult Problems 5. RLD is 1 of these problems Being Mortal By Atul Gawanda

57 Welcome to the Mission Bill Davies PAC RRT Captain Kirk YOU

58 Any Questions? Bill Davies, PAC, RRT