Bronchial airflow limitation and chest findings in adults with respiratory infection

Abstract

Objective - To study the predictive value of clinical chest findings for bronchial airflow limitation in patients with respiratory tract infection.

Design - Associations were analysed between FEV₁ (forced expiratory volume in one second) in % of predicted and physical chest findings.

Setting - the Municipal Emergency Clinic in Tromsø, Norway.

Participants - 398 adult patients with respiratory tract infection and 40 general practitioners.

Outcome measures - Mean FEV₁% predicted and frequency of FEV, <80% predicted according to chest findings. Regression coefficients of the findings with FEV % predicted as outcome variable.

Results - Mean FEV₁% predicted was 87 (range 25-129). Pathological chest findings were recorded in 127 patients (32%) and in 22 of the 24 patients (92%) with FEV₁% predicted less than 60. the 78 patients with wheezes had a mean FEV¹% predicted of 74 (range 29-120), significantly lower than those without wheezes (p<0.0001), and 63% had FEV₁ predicted less than 80. Prolonged expiration or strenuous respiration was recorded in 49 patients. the 29 patients with wheezes in this subgroup had a significantly lower mean FEV¹% predicted, 65, than the 20 patients without wheezes (p<0.005). by multiple regression wheezes and strenuous respiration were the most significant predictors of FEV¹% predicted, together with patients' statement of very annoying dyspnoea.

Conclusion - When predicting the degree of bronchial obstruction in a patient with respiratory infection, the doctor may take into account wheezes heard by auscultation, an impression of strenuous respiration, and the patient's statement about severe dyspnoea.

Key Words:

• bronchial obstruction
• wheezes
• chest signs
• spirometry
• respiratory infection