Coexistence of confirmed obstruction in spirometry and restriction in body plethysmography, e.g.: COPD + pulmonary fibrosis

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1 Volumes: IRV inspiratory reserve volume Vt tidal volume ERV expiratory reserve volume RV residual volume Marcin Grabicki Department of Pulmonology, Allergology and Respiratory Oncology Poznań University of Medical Sciences Capacities: IC inspiratory capacity VC vital capacity FRC functional residual capacity TLC total lung capacity Obstruction narrow or collapsed bronchi resulting in airflow limitation Restriction decreased TLC as a consequence of structural or functional reduction of alveoli number (lung parenchyma) Mixed obstruction + restriction Inside the bronchi: constriction and hypertrophy of bronchi smooth muscles edema and hypertrophy of airways mucosa excessive excretion of thick mucus partial narrowing of the bronchus by the foreign body or tumor Outside the bronchi: damage of recoil resulting in collapsing of bronchiole compression of the bronchial wall by the tumor or enlarged lymph nodes COPD (chronic bronchitis, emphysema) Asthma Endobronchial tumor Bronchiectasis CF 1

2 Lung diseases Pleura diseases Pathologies of the abdomen Impaired muscles function Limitation of the chest movements Other Lungs: Pneumonia Atelectasis Lung tumor Interstitial diseases Lung surgery Pleura: Hydrothorax Pneumothorax Fibrosis of pleural space Abdomen: Obesity Ascites Liver tumor Hepatomegaly Advanced pregnancy Chest wall: Ribs fracture Spinal column deviation Diseases of the neuromuscular system Other: Heart failure, PE Coexistence of confirmed obstruction in spirometry and restriction in body plethysmography, e.g.: COPD + pulmonary fibrosis No TLC information no restriction (mixed) diagnosis; only obstruction with decreased (F)VC Spirometry Body plethysmography CO diffusing capacity to diagnose ventilatory disturbance: obstruction suspicion of restriction confirmation in body plethysmography to assess the severity of airflow limitation to monitor the disease course (mainly COPD and asthma) Static spirometry measurement of lung volumes during the normal breathing Dynamic spirometry measurement of the intensity and volume of the airflow during the forced breathing to estimate the efficacy of treatment 2

3 FEV1 forcedexpiratoryvolumein1second FVC forcedvc FEV1/(F)VC ratio; (pseudo)tiffeneau PEF peakexpiratoryflow FET forcedexpiratorytime It is the routine test which should be done in most patients with any pulmonary problem. Diagnostic: to evaluate symptoms, signs or abnormal laboratory tests to measure the effect of disease on pulmonary function to screen individuals at risk of having pulmonary disease to assess pre-operative risk to assess prognosis to assess health status before beginning strenuous physical activity programmes Monitoring: to assess therapeutic intervention to describe the course of diseases that affect lung function to monitor people exposed to injurious agents to monitor for adverse reactions to drugs with known pulmonary toxicity Disability/impairment evaluations : to assess patients as part of a rehabilitation programme to assess risks as part of an insurance evaluation to assess individuals for legal reasons Public health : epidemiological surveys derivation of reference equations clinical research Absolute: recent eye surgery (increases in intraocular pressure) recent thoracic or abdominal surgery recent myocardial infarction, unstable angina or stroke cerebral, thoracic and abdominal aneurysms (risk of rupture because of increased thoracic pressure) hemoptysisof unknown origin pneumothorax Relative: bad cooperation with a patient intensive cough acute disorders affecting test performance (e.g., vomiting, nausea, vertigo) chest or abdominal pain of any cause 3

4 provide appropriate subject preparation and position provide information on how to perform spirometry correctly record subject data (race, age, sex, height, weight) accurately perform test smoking within at least 1 h of testing consuming alcohol within 4 h of testing performing vigorous exercise within 30 min of testing wearing clothing that substantially restricts full chest and abdominal expansion eating a large meal within 2 h of testing The acceptability criteria: Flow volume curve (loop): satisfactory start of test (PEF) appropriate shape ( expiration sail, inspiration - boat ) closed loop and no artefacts (e.g., without coughing during the first second of the manoeuvre) satisfactory EOT (expir. at least 6 sec., no change in volume) without a leak without evidence of an extra breath being taken during the manoeuvre The repeatability criteria: The test meets the repeatability criteria if 2 highest results of FVC and FEV1 from at least 3 manoeuvres differ from each other less than 100ml (max. 150 ml). The repeatability criteria Restrictive Obstructive 4

5 FEV1/(F)VC < (5 percentile; LLN) (~ 70%) Severity of obstruction - FEV1 (% pred.): - Mild 70 - Moderate Moderately severe Severe Very severe 34 FEV1/FVC < 70% (???< 5 percentile; < LLN) FEV1 (% pred.): - Mild 80 - Moderate Severe Very Severe 29 Bronchodilators can be used in selected patients following the initial spirometry. Response to bronchodilators suggests asthma, but other obstructive lung disorders can respond to bronchodilators as well. Pre-bronchodilator spirometry The test is positive if: FEV1 or FVC increased at least: Inhalation of bronchodilator (4 puffs of salbutamol 400 mcg) 200ml AND 15 minutes 12% (FEV1 post FEV1 pre/fev1 prex 100%) 12 % Itis a test used to help in diagnosing or excluding asthma by provoking a bronchoconstrictionresponse to a controlled external stimulus The external stimulus varies according to the type of suspected asthma Post-bronchodilator spirometry Pharmacologic inhalation challenge: metacholine histamine mannitol Exercise challenge Antigen challenge Aspirin challenge A significant bronchoconstrictive response: a drop in FEV 1 by 20% of its baseline value The degree of airway reactivity: the dose or concentration (PD 20 or PC 20) of inhaled pharmacologic stimulus resulting in significant bronchoconstriction The lower the PD 20or PC 20, themore severe the responsiveness is 5

6 TLC <(5 pc; LLN) Severity [% pred.] Mild 70 < (5 pc; LLN) Moderate Severe 59% DLCO (< 5 pc, LLN) FEV1/(F)VC (5 pc; LLN) (~ 70%) Severity [% pred.] (F)VC Mild 61 < (5 pc; LLN) (5 pc; LLN) (~ 80% pred.)? < (5 pc; LLN) < (~ 80% pred.)? Moderate Severe 39% Norm FEV1 LLN (F)VC restriction susp. FEV1<LLN Clinical assessment Stage of (F)VC Body plethysmography (TLC) FEV1/(F)VC < (5 pc; LLN) ( ~ 70%) Obstruction Severity of obstruction(fev1 %pred.) Reversibility test 6