Assessment
Clinical Examination for Prediction of Airflow Obstruction ÎCigarette smoking is the most common cause of COPD. > A 70-pack-year history of smoking is the best predictor of AO.
ÎFindings from physical examination have high specificity (90%) but poor sensitivity.
> Sputum production or wheezing is also associated with an increased likelihood of AO. ÎCombinations of findings are more helpful for diagnosing the presence of AO.
> The best combination to exclude COPD includes never having smoked, no reported wheezing, and no wheezing on examination.
< 60% predicted or FEV1 /FVC ratio < 0.60).
> A patient with any combination of 2 findings (≥ 70-pack-year history of smoking, history of COPD, or decreased breath sounds) can be considered likely to have AO (defined as FEV1
Incremental Value of Spirometry
ÎIn patients with respiratory symptoms, particularly dyspnea, spirometry should be performed to diagnose airflow obstruction (Rec: Strong; Evid: Moderate Qual).
ÎSpirometry may be useful to identify patients who may benefit from initiating therapy (Table 1).
ÎEvidence supports inhaled bronchodilator treatment in patients who have symptoms and FEV1
< 60% predicted (Rec: Strong; Evid: Moderate Qual). ÎRespiratory symptom status is not a reliable indicator of the presence of AO.
> However, as spirometric values worsen, individuals report more respiratory symptoms, such as cough, sputum, wheezing, or dyspnea.
ÎEvidence is insufficient to support widespread use of spirometry for testing adults with no respiratory symptoms, including those with current and past exposure to COPD risk factors (Rec: Strong; Evid: Moderate Qual).
ÎSpirometry may be beneficial for determining when to initiate therapy in symptomatic adults who have an FEV1
> 60% predicted.
> Evidence does not support periodic spirometry after initiation of therapy to monitor ongoing disease status or to modify therapy.
Additional Testing
ÎIn addition to spirometry, the following other tests may be considered for the assessment of a patient with ≥ Moderate (Stage II) COPD:
> Bronchodilator reversibility: To rule out a diagnosis of asthma. > Chest X-ray: To exclude alternative diagnoses. > Arterial blood gases: Perform in patients with FEV1 signs suggestive of respiratory or right heart failure.
< 50% predicted or with clinical
> Alpha-1 antitrypsin deficiency: Perform when COPD develops in patients of Caucasian descent under 45 years or with a strong family history of COPD.
