Obstructive and restrictive Lung Disease Jed Wolpaw MD, M.Ed

Outline Obstructive disease Restrictive disease Upper airway Extrathoracic INtrathoracic Lower airway/Parenchymal Restrictive disease Neurologic Muskuloskeletal Parenchymal Pleural and mediastinal other

Obstructive disease: Upper airway

Upper airway From mouth to lower trachea

Intra vs Extrathoracic Which lesion limits inspiratory flow the most? A: Variable upper airway extrathoracic obstruction B: Variable upper airway intrathoracic obstruction C: COPD D: Asthma

Intra vs Extrathoracic Which lesion limits inspiratory flow the most? A: Variable upper airway extrathoracic obstruction B: Variable upper airway intrathoracic obstruction C: COPD D: Asthma

Intra vs extra thoracic

How to read a flow volume loop Where is: -Flow? -Volume? -Inspiration? -Expiration? -Total Lung Capacity? -End Exhilation (residual volume)?

How to read a flow/volume loop

Name that obstruction

Intrathoracic versus extrathoracic VOLUME IS THE SAME, FLOW IS LIMITED

Lesions at the thoracic inlet Starts intrathoracic Shifts to extrathoracic

FEF50%/FIF50% Forced expiratory flow at 50% vital capacity/forced inspiratory flow at 50% VC Extrathoracic: Increased to average 2.2 from normal 1 Intrathoracic: Decreased to average 0.32 from normal 1 Fixed obstruction: around 1

Causes of upper airway obstruction: Intra or extrathoracic depending on location Congenital: tracheomalacia (upper), laryngomalacia, vocal cord abnormalities, vascular rings, laryngeal webs, scoliosis (can compress trachea) Infectious: epiglottitis, peritonsillar abscess, Retropharyngeal abscess, Ludwig’s angina, Diptheria, Croup Tumors Trauma: Neck hematoma, fracture, Burns Foreign body Soft tissue: osa, nerve palsies

Obstructive disease: lower airway/parenchymal

Lower airway/Parenchymal obstructive diseases Asthma Emphysema Bronchitis CF: bronchiectasis Mediastinal masses

Mechanisms Officially these are no longer separated and are all copd (if asthma isn’t completely reversible Asthma: thickened/tightened airway smooth muscle and excess mucous CD4+ cells, T lymphocytes, eosinophils, IL-4 and IL-5 Emphysema: dilation/destruction of airway distal to terminal bronchiole (acinus) CD8+ T-lymphocytes, neutrophils, and CD68+ monocytes/macrophages Chronic bronchitis: Excess mucous, airway thickening

COPD/Asthma/Bronchitis overlap

acinus

Loops

Spirometry FVC: Forced vital capacity FEV1: Forced expiratory volume FEV1/FVC: Ratio of these two FEF 25-75%: Forced expiratory flow from 25-75% of vital capacity Thought to be effort independent Mvv: Maximum voluntary expiration (how much can one inhale and exhale in 1 minute)

Spirometry

DLCO (Diffusion capacity for carbon monoxide) Measures the ability of the lungs to transfer o2 to the blood Obstructive disease Correlates with degree of emphysema Smokers with airway obstruction but normal dlco have bronchitis but not emphysema Asthmatics have normal or high dlco Cystic fibrosis: normal until very late in disease

Cystic Fibrosis Mutation in CFTR leading to inability to transport chloride and sodium Autosomal recessive Multiple organ systems effected, we will focus on respiratory Life expectancy average 39 years

What is bronchiectasis A: Chronic airway infection B: Recurrent pneumonia in cystic fibrosis C: Dilation of airways due to wall destruction D: being the subject of excess bronchoscopies

What is bronchiectasis A: Chronic airway infection B: Recurrent pneumonia in cystic fibrosis C: Dilation of airways due to wall destruction D: being the subject of excess bronchoscopies

CF: Bronchiectasis Inability to transport Cl- and Na+ effectively leads to thickened secretions Leads to colonization w organisms Leads to massive inflammation from neutrophil degranulation Leads to destruction of bronchus walldilation of airways Leads to more mucous Leads to more infection

Bronchiectasis

CF: Why pseudomonas? Increased o2 utilization by lung epithelial cells causes local hypoxia This causes pseudomonas to gain the ability to make biofilms Almost impossible to eradicate at that point

Mediastinal masses Anterior, middle and posterior mediastinum For airway compromise most significant is anterior Most common: terrible t’s Teratoma Thymoma Thyroid tissue “terrible lymphoma”

What is the safest way to induce a patient with an anterior mediastinal mass compressing the airway? A: RSI with Sux and etomidate B: Asleep fiber C: Awake fiber with surgeon standing by ready to perform tracheostomy D: Awake fiber after cannulating groin vessels for ecmo

What is the safest way to induce a patient with an anterior mediastinal mass compressing the airway? A: RSI with Sux and etomidate B: Asleep fiber C: Awake fiber with surgeon standing by ready to perform tracheostomy D: Awake fiber after cannulating groin vessels for ecmo

Mediastinal mass CXR

Mediastinal mass can cause both obstructive (compressing trachea) or restrictive (reducing compliance of lungs) pathology Can compress: Airways Vessels (SVC) Heart

Mediastinal mass Preparation Groin line in case of svc obstruction Awake intubation with spontaneous ventilation in case of airway obstruction Avoid neuromuscular blockade if possible If imaging/symptoms very concerning cannulate for ecmo/bypass first Crichothyrotomy will not help here

All the loops