Accuracy of Ultrasound in Diagnosis of Pneumothorax: A Comparison between Neonates and Adults—A Systematic Review and Meta-Analysis

OBJECTIVE: The present systematic review and meta-analysis were conducted to investigate the accuracy of ultrasound in the diagnosis of pneumothorax in neonates and adults. METHOD: The searches were conducted by two independent researchers (MS and HD) to find the relevant studies published from 01/01/2009 until the end of 01/01/2019. We searched for published literature in the English language in MEDLINE via PubMed, Embase™ via ovid, the Cochrane Library, and Trip database. For literature published in other languages, we searched national databases (Magiran and SID), KoreaMed, and LILACS, and we searched OpenGrey (http://www.opengrey.eu/) and the World Health Organization Clinical Trials Registry (http://who.int/ictrp) for unpublished literature and ongoing studies. The keywords used in the search strategy were pneumothorax or ultrasound or chest ultrasonography or neonate or adult or aerothorax or sensitivity or specificity or diagnostic accuracy. The list of previous study resources and systematic reviews was also searched for identifying the published studies (MS and HD). Analyses were performed using Meta-Disc 1.4. RESULTS: In total, 1,565 patients (255 neonates, 1212 adults, and 101 pediatrics suspected of pneumothorax) were investigated in 10 studies. The overall specificity of chest ultrasound in the diagnosis of pneumothorax in both populations of adults and neonates was 85.1% at the confidence interval of 95 percent (95% CI 81.1%–88.5%). At the confidence interval of 95 percent, the sensitivity was 98.6% (95% CI 97.7%–99.2%). The diagnostic odds ratio was 387.72 (95% CI 76.204–1972.7). For the diagnosis of pneumothorax in neonates, the ultrasound sensitivity was 96.7% at the confidence interval of 95 percent (95% CI 88.3%–99.6%). At the confidence interval of 95 percent, the specificity was 100% (95% CI 97.7%–100%). For the diagnosis of pneumothorax in adults, the ultrasound sensitivity was 82.9% at the confidence interval of 95 percent (95% CI 78.3–86.9%). At the confidence interval of 95 percent, the specificity was 98.2% (95% CI 97.0%–99.0%). The diagnostic odds ratio was 423.13 (95% CI 45.222–3959.1). Analyzing studies indicated that the sensitivity of “absence lung sliding” sign for the diagnosis of pneumothorax was 87.2% (95% CI 77.7–93.7), and specificity was 99.4% (95% CI 96.5%–100%). DOR was 556.74 (95% CI 100.03–3098.7). The sensitivity of “lung point” sign for the diagnosis of pneumothorax was 82.1% (95% CI 71.7%–89.8%), and the specificity was 100% (at the confidence interval of 95% CI 97.6%–100%). DOR was 298.0 (95% CI 58.893–1507.8). CONCLUSION: The diagnosis of pneumothorax using ultrasound is accurate and reliable; additionally, it can result in timely diagnoses specifically in neonatal pneumothorax. Using this method facilitates the therapy process; lack of ionizing radiation and easy operation are benefits of this imaging technique.