Diagnosis of obstructive airways disease from the clinical examination

Abstract

Objective: To determine the operating characteristics of history and physical examination items for pulmonary airflow obstruction.

Design: Prospective observational study.

Setting: Medical Preoperative Evaluation Clinic at the Durham Veterans Affairs Medical Center.

Patients/participants: Consecutive patients referred for outpatient medical preoperative risk assessment.

Interventions: None.

Measurements and main results: Number of years the patient had smoked cigarettes, patient-reported wheezing [LR⁺ (likelihood ratio for finding present)=3.1; LR⁻ (likelihood ratio for finding absent)=0.58], and auscultated wheezing (LR⁺=12; LR⁻=0.87) were independent predictors of obstructive airways disease from the history and physical examination. Forced expiratory time and peak expiratory flow rate, both measured by the clinician at the bedside, were additional independent predictors of airflow obstruction. A nomogram using patient-reported wheezing, number of years the patient had smoked, and auscultated wheezing was developed and validated (area under receiver operating characteristic curve=0.78; p=0.0001) for the bedside prediction of obstructive airways disease. Peak expiratory flow rate can be substituted for auscultated wheezing with similar predictive ability.

Conclusions: The results of bedside clinical examinations predict the presence of obstructive airways disease. A nomogram based on a combination of four bedside findings predicts airflow obstruction as well as clinicians’ overall clinical impressions.