Lung ultrasound has greater accuracy than conventional respiratory assessment tools for the diagnosis of pleural effusion, lung consolidation and collapse: a systematic review

Abstract

Question: In mechanically ventilated adults in intensive care, what is the accuracy of lung ultrasound (LUS) for the diagnosis of pleural effusion, lung consolidation and lung collapse when compared with chest radiograph (CXR) and lung auscultation, with computed tomography (CT) as the reference standard?

Design: Systematic review with meta-analysis of prospective cohort studies.

Participants: Adult patients admitted to intensive care, with diagnostic uncertainty at enrolment regarding pleural effusion, lung consolidation and/or collapse/atelectasis.

Index test: The diagnostic accuracy of LUS as the index test was estimated against CXR and/or lung auscultation as comparators, with thoracic CT scan as the reference standard.

Outcome measures: Measures of diagnostic accuracy.

Results: Seven eligible studies were identified, five of which (with 253 participants) were included in the meta-analysis. It was found that LUS had a pooled sensitivity of 92% and 91% in the diagnosis of consolidation and pleural effusion, respectively, and pooled specificity of 92% for both pathologies. CXR had a pooled sensitivity of 53% and 42% and a pooled specificity of 78% and 81% in the diagnosis of consolidation and pleural effusion, respectively. A meta-analysis for lung auscultation was not possible, although a single study reported a sensitivity and specificity of 8% and 100%, respectively, for diagnosing consolidation, and a sensitivity and specificity of 42% and 90%, respectively, for diagnosing pleural effusion.

Conclusion: This systematic review with meta-analysis demonstrated high sensitivity of LUS compared with CXR, with similar specificities when diagnosing pleural effusion and lung consolidation/collapse.

Registration: PROSPERO CRD42018095555.

Keywords: Diagnosis; Meta-analysis; Pleural effusion; Systematic review; Ultrasonography.