Chronic Obstructive Pulmonary Disease (COPD): Diagnostic Tests

Mandatory medical device diagnostics.

• Spirometry (basic examination as part of pulmonary function diagnostics) – part of initial diagnostics/stage 1.
  • [COPD is classified according to GOLD (Global Initiative for Chronic Obstructive Lung Disease) based on FEV1: see below.
  • Bronchial asthma:
    • Evidence of obstruction (narrowing or obstruction of the airways): FEV1 (expiratory one second capacity or forced expiratory volume) decreased and FEV 1 / VC < 70% (VC = vital capacity).
    • Evidence of reversibility: (approximate) normalization after bronchospasmolysis / drug relaxation of the contracted, i.e. “cramped” bronchial musculatureFor bronchial asthma speak in the bronchospasmolysis test (administration of a bronchodilator drug) a normalization of FEV1 or an additional intake of more than 400 ml.
  • Caution. According to one study, 54.1% of (ex-)smokers without spirometric evidence of COPD (GOLD 0) have at least one clinically or radiologically detectable lung lesion.
• Caution. According to one study, 54.1% of (ex-)smokers without spirometric evidence of COPD (GOLD 0) have at least one clinically or radiologically detectable lung lesion.
• Bodyplethysmography (whole-body plethysmography; large lung function) – initial diagnosis/stage 2; provides information on the degree of pulmonary hyperinflation (emphysema) and the extent of airway obstruction:
  • COPD
    • COPD severity 1-2(-3): residual volume (RV; amount of air remaining in the lungs after maximal expiration) unremarkable or slightly increased
    • COPD severity grade 4 (with emphysema): RV significantly increased.
  • Bronchial asthma: RV unremarkable
  • Heart failure (cardiac insufficiency): RV unremarkable
  • Interstitial lung disease: total lung capacity (TLC) decreased.
• X-ray of the thorax (X-ray thorax/chest), in two planes; part of the initial diagnosis.
  • COPD
    • COPD severity 1-2(-3): unremarkable
    • COPD severity 4 (with emphysema): diaphragmatic depression, flattened diaphragms, horizontal ribs, increased radiolucency, decreased pulmonary vascularity.
  • Bronchial asthma: unremarkable
  • Heart failure: increased pulmonary vascularity, cardiomegaly (enlargement of the heart).
  • Interstitial lung disease: interstitial and/or fine-spotted drawing proliferation.

COPD is classified according to GOLD (Global Initiative for Chronic Obstructive Lung Disease) based on FEV1 as follows:

Notice:

• One in two smokers who did not (yet) meet the criteria for chronic obstructive pulmonary disease (COPD) on spirometry [Tiffeneau index (forced one-second capacity (FEV1)/forced vital capacity (FVC) > 70%)] had a CAT score (COPD Assessment Test, see history below) of 10 or more, meaning they suffered from symptoms of COPD.
• In the elderly, a Tiffeneau index (FEV1/FVC) of less than 0.7 may still be normal!

Optional medical device diagnostics – depending on the results of the history, physical examination, laboratory diagnostics and obligatory medical device diagnostics – for differential diagnostic clarification.

• Echocardiography (echo; cardiac ultrasound) wg.
  • Suspicion of cor pulmonale (right heart failure) [often mild form of pulmonary hypertension (PH)/pulmonary hypertension].
  • Testing of systolic and diastolic left ventricular function.
• Perfusion stress MRI: e.g., adenosine stress MRI: in which healthy arteries dilate by up to 5 times their original diameter after administration of adenosine [demonstrated perfusion defects of the myocardium allow identification of diseased coronaries].
• Computed tomography of the thorax/chest (thoracic CT) – necessary before surgical interventions or in cases of suspected tumors, bronchiectasis (synonym: bronchiectasis; saccular or cylindrical dilatations of the airways (bronchi))
• Quantitative computed tomography (qCT) – to visualize anatomical structures and functional lung parameters [detection of areas where air gets “stuck” during exhalation (“air trapping”)].
• Electrocardiogram (ECG; recording of the electrical activity of the heart muscle) – if cardiac arrhythmia or cardiac hypertrophy is suspected.
• 6-minute walk test – standardized procedure for objective assessment, determination of severity, and progression of exercise limitation attributable to cardiopulmonary causes.
• Reversibility test using bronchospasmolysis (drug-induced relaxation of contracted, i.e. “cramped” bronchial muscles) – enables differentiation between bronchial asthma and COPDFirst, a peak flow measurement (measurement of expiratory volume) is performed. If the value is decreased, a bronchodilator (brochodilator) spray (beta-2-sympathomimetic: e.g. – 400 μg salbutamol) or anticholinergic (- 160 μg ipratropium) or a glucocorticoid (20-40 mg prednisolone equivalent over 14 days or inhaled at least medium-high cortisone doses over 4-6 weeks) is administered. This tests whether the airways can be widened by this measure. If this is the case, then the peak flow value also improves significantly and there is most likely a bronchial asthma.If the previously lowered peak flow value remains lowered even after the attempt to expand the airway, this speaks more for a chronic obstructive pulmonary disease (COPD).
• FeNO measurement (synonyms: Determination of nitric oxide concentration (FENO) in exhaled air; multiple breath test method, FENO test) – biomarker of inflammation/diagnostic method for determining the level of FeNO (nitric oxide) in exhaled air to detect the presence of inflammatory processes and chronic pulmonary disease:
  • COPD: usually normal; decreased in former smokers.
  • Bronchial asthma: > 50 ppb (high level), in nonsmokers supports diagnosis of eosinophilic airway inflammation (airway inflammation)
• A determination of CO diffusing capacity (synonyms: carbon monoxide diffusing capacity, carbon monoxide transfer factor (TLCO); pulmonary diffusion measurement; English : Diffusing capacity or Transfer factor of the lung for carbon monoxide, DLCO) can be used to diagnose COPD. [In the case of COPD on the floor of emphysema often lowered / marker of early COPD; in asthma normal or slightly elevated].
• In patients who have severe dyspnea on exertion or signs of right heart strain, arterial blood gas analysis (a method of measuring the gas distribution of O2 (oxygen), CO2 (carbon dioxide), and pH and acid-base balance in the blood) should be performed at rest and, if necessary, on exertion.

Pulmonary Round Heart (LRH)

A pulmonary round focus is defined as an intrapulmonary parenchymal thickening less than 3 cm in diameter that is not associated with atelectasis or a pathologically enlarged lymph node. Recommendations for the approach to pulmonary round lesions are based on the 2005 Fleischer criteria (Fleischner Society guidelines (FSG)):

The indicated controls are CT examinations.