Lung Ultrasound for Acute Respiratory Distress Syndrome Diagnosis: A Systematic Review and Meta-analysis

Background/Objectives: Acute respiratory distress syndrome (ARDS) requires prompt diagnosis.Lung ultrasound (LUS) is a non-invasive tool with potential diagnostic value, but its accuracy needs systematic evaluation.Methods: A systematic search of PubMed, Embase, Cochrane Library, and Web of Science (inception-December 2024) identified studies assessing LUS for ARDS using established reference standards.Data were extracted independently, and a random-effects meta-analysis was performed to calculate diagnostic odds ratios (DOR), sensitivity, specificity, likelihood ratios, and AUROC.Results: This meta-analysis included 16 studies with 5,888 patients, demonstrating that lung ultrasound (LUS) is a reliable diagnostic tool for ARDS.The pooled diagnostic odds ratio was 14.98 (95% CI, 9.81-22.88;p < .001),with a sensitivity of 0.75 (95% CI, 0.62-0.85)and specificity of 0.87 (95% CI, 0.80-0.91).The positive and negative likelihood ratios were 4.89 (95% CI, 3.67-6.52)and 0.15 (95% CI, 0.11-0.21),respectively, while the AUROC was 0.91 (95% CI, 0.88-0.93).Substantial heterogeneity was noted (I = 75.2%),with higher diagnostic performance observed in ICU settings, studies using 8-zone scanning protocols, and those focusing on severe ARDS.Meta-regression identified scanning zones and operator experience as key sources of heterogeneity.The presence of bilateral B-patterns with 3 Blines per intercostal space showed the highest specificity (0.92; 95% CI, 0.87-0.96).Conclusions: This meta-analysis demonstrated that LUS has good diagnostic accuracy for ARDS (pooled DOR 14.98, sensitivity 0.75, specificity 0.87, AUROC 0.91).Higher diagnostic performance was observed with 8-zone scanning protocols, in ICU settings, and for severe ARDS.The modest sensitivity indicates that negative LUS findings should not exclude ARDS diagnosis.Clinical Implications: Lung ultrasound (LUS) provides a rapid, bedside, and radiation-free diagnostic option for ARDS, offering good accuracy, especially in ICU and resource-limited settings.Comprehensive scanning protocols and trained operators enhance reliability, supporting LUS integration into clinical practice where advanced imaging is unavailable.