Sonographic B-Lines and Pressure of End Tidal CO2 in Differentiating Acute Dyspnea, HAMDY M. HASSABALLA, AHMED SAMIR, MERVAT KHALAF, KHALID A. AL-WAHAB and WAHEED A. RADWAN
Abstract
Introduction: Acute dyspnea is a common presentation in the Emergency Department and critical care setting. Early differentiation of cardiac causes of dyspnea from pulmonary related causes is of great significance. Clinical data including history and clinical examination may sometimes fail to dif-ferentiate the cause of dyspnea. Point of care lung ultrasound and pressure of end tidal CO2 may add more diagnostic accuracy.
Objectives: Our study compared the diagnostic accuracy of clinical criteria for diagnosis of heart failure related acute dyspnea as calculated with modified Boston criteria to pressure of end tidal CO2 and to b lines on lung ultrasound.
Methods: We conducted a prospective study. In Cairo University Hospitals, between December 2012 to February 2014, 250 patients with acute dyspnea were recruited, of whom 25 patients were excluded. 225 patients were subdivided based on final hospital diagnosis into heart failure related acute dyspnea group (n=118) and pulmonary (asthma/COPD) related acute dyspnea group (n=107). History, clinical exam-ination, standard laboratory tests, chest X-ray, lung ultrasound for bilateral symmetrical b lines and pressure end tidal CO2 level were collected.
Results: Lung ultrasound had the best performance, with sensitivity 100% and specificity of 94% and Area Under the Receiver-Operating Curve (AUROC) 0.98. Clinical evaluation using modified Boston criteria had sensitivity 85% and spe-cificity of 83% and AUROC 0.96. The pressure of end tidal CO2 had sensitivity 79% and specificity of 79% and AUROC 0.94.
Conclusions: Point of care lung ultrasound gives accurate differentiation between cardiac related acute dyspnea from pulmonary related acute dyspnea.