A Prospective Observational Study Comparing the Diagnostic Use of Point-of-Care Lung Ultrasound with Chest X-Ray in Acute Dyspnoea in the Emergency Department.

Abstract

Introduction: Acute dyspnea is a common and critical presentation in the Emergency Department (ED), requiring rapid and accurate diagnosis for effective management. While Chest X-ray (CXR) has traditionally been used as the first-line imaging modality, Point-of-Care Ultrasound (POCUS) has emerged as a promising bedside diagnostic tool. This study aimed to compare the diagnostic accuracy and efficiency of POCUS with CXR in evaluating patients presenting with acute dyspnea in the ED.

Methods: A prospective observational study was conducted in the Department of Emergency Medicine, Madras Medical College and Rajiv Gandhi Government General Hospital, Chennai. A total of 122 patients fulfilling the inclusion and exclusion criteria were enrolled in the study. All patients underwent Point-of-Care Ultrasound (POCUS) and Chest X-ray (CXR), and CT chest was taken as the gold standard for the final diagnosis. Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and overall diagnostic accuracy were calculated for both modalities.

Results: Point-of-Care Ultrasound (POCUS) showed a high sensitivity of 92.31%, specificity of 90.91%, positive predictive value (PPV) of 94.74%, negative predictive value (NPV) of 86.96%, and an overall diagnostic accuracy of 91.8%. In contrast, Chest X-ray (CXR) showed a sensitivity of 74.36%, specificity of 81.82%, positive predictive value (PPV) of 87.88%, negative predictive value (NPV) of 64.29%, and diagnostic accuracy of 77.05%. Point-of-Care Ultrasound (POCUS) significantly reduced the time to diagnosis, especially in patients with Grade III dyspnea, where the average time taken was 3 ± 1.5 minutes. The findings of the study reveal that POCUS is a rapid, reliable, and useful bedside diagnostic tool in the assessment and management of acute dyspnea when compared to conventional chest X-ray, although it was found to be less effective in detecting pulmonary tuberculosis.

Conclusion: POCUS outperformed CXR in terms of diagnostic accuracy, speed, and clinical utility in patients with acute dyspnea. Its bedside applicability, real-time interpretation, and avoidance of patient transport make it an essential tool in the emergency department, particularly for critically ill or hemodynamically unstable patients. Integration of POCUS into routine emergency care workflows can enhance early diagnosis, expedite clinical decision-making, and ultimately improve patient outcomes in acute respiratory emergencies.