Spirometery

Lung Volumes 4 Volumes 4 Capacities Sum of 2 or more lung volumes IRV TV ERV RV IC FRC VC TLC RV

Relative Contraindications to Performing Spirometry Hemoptysis of unknown origin Pneumothorax Unstable cardiovascular status or recent myocardial infarction or pulmonary embolus Thoracic, abdominal, or cerebral aneurysms Recent eye surgery Presence of an acute disease process that might interfere with test performance (eg, nausea, vomiting) Recent surgery of thorax or abdomen Patients with a history of syncope associated with forced exhalation

Classification of Impairment

Spirometry Flow Loop- Normal

Standards for Testing Technical Requirements for Good Quality Full inhalation before start of test Satisfactory start of exhalation Evidence of maximal effort No hesitation No cough or glottic closure during first second Duration of test 3-6 seconds Up to 10 seconds in patients with obstruction No evidence of leak No evidence of obstruction of mouthpiece

Spirometry Quality

Example of Glottic Closure Normal Glottic closure Flow ceased

Recognizing Artifact

Acceptable and Unacceptable Spirograms

Normal Flow Volume Loop RV TLC FRC Flow Ex. In Vol.

January 2009 Normal Flow Volume Curve

Obstructive Flow Volume Loop RV TLC FRC Flow Ex. In Vol Note the Concave Expiratory Flow Loop.

Obstructive Disorders Characterized by reduction in exp flow rates not attributable to decreased lung volumes FEV1/FVC  TLC is N or  if lung elastic recoil is decreased (as in emphysema) FRC and RV are typically  (may be N) FVC may be  by large increase in RV

Flow-volume loops and upper airway obstruction Extrathoracic obstruction – vocal cord dysfunction, goiter, cause flattening of inspiratory limb of flow/volume loop Intrathoracic obstruction – bronchogenic cancer in right mainstem bronchus, flattening of expiratory limb of flow/volume loop

Variable Extrathoracic Airway Obstruction RV TLC FRC Flow Ex. In Vol Normal expiratory flow, but diminished inspiratory flow (ie. its variable).

Variable Extrathoracic Obstruction Unilateral and bilateral vocal cord paralysis Vocal cord adhesions Vocal cord constriction Laryngeal edema Upper airway narrowing associated with obstructive sleep apnea

Variable Intrathoracic Obstruction Localized tumors of the lower trachea or mainstem bronchus Tracheomalacia Airway changes associated with polychondritis

Fixed Airway Obstruction RV TLC FRC Flow Ex. In Vol Note that both inspiratory flow and expiratory flow are “flat” due to decreased flow.

Fixed Upper Airway Obstruction Goiters Endotracheal neoplasms Stenosis of both main bronchi Postintubation stenosis Performance of the test through a tracheostomy tube or other fixed orifice device.

Flow-Volume Loops (Rudolph and Rudolph, 2003)

ActualPredicted% Predicted FVC FEV FEV1/FVC FEF

ActualPredicted% Predicted FVC FEV FEV1/FVC FEF Small Airways Defect

Bronchodilator Response: Response to inhaled bronchodilators: Typical in asthma; some patients with COPD and CF have reversibility also “Real response”: consists of a change in FEV1 by at least 12% (and 200cc) after inhalation of albuterol

ActualPredicted% Predicted FVC FEV FEV1/FVC FEF ActualPredicted% Predicted FVC FEV FEV1/FVC FEF Beta agonist treatment Reversible obstructive defect

Restrictive Disorders Volume of air within the lung  by: Space-occupying abnormalities in the thorax (effusion, tumor) Parenchymal infiltration (fibrosis, fluid, inflam.) Alveolar collapse Respiratory muscle weakness Abnormal recoil or deformity of the chest wall RV  (but  if there is exp muscle weakness) FRC  (but N if resp muscle weakness) FEV1/FVC is N or 

Common Causes of Restrictive Ventilatory Defects Interstitial lung disease Interstitial pneumonitis Fibrosis Pneumoconiosis Granulomatosis Edema Space-Occupying Lesions Tumor Cysts Pleural Diseases Pneumothorax Hemothorax Pleural effusion, empyema Fibrothorax Chest-Wall Diseases Injury Kyphoscoliosis Spondylitis Neuromuscular disease Extrathoracic Conditions Obesity Peritonitis Ascites Pregnancy

ActualPredicted% Predicted FVC FEV FEV1/FVC FEF25-75 Restrictive Pattern

Restrictive Lung Disease Characterized by diminished lung volume due to: change in alteration in lung parenchyma (interstitial lung disease) disease of pleura, chest wall (e.g. scoliosis), or neuromuscular apparatus (e.g. muscular dystrophy) Decreased TLC, FVC Normal or increased: FEV 1 /FVC ratio

ActualPredicted% Predicted FVC FEV FEV1/FVC FEF Restrictive pattern in obese patient