For a study, researchers sought to confirm the role of the Macklin effect on chest CT imaging in predicting the development of pneumomediastinum/pneumothorax (PMD/PNX) in COVID-19 patients. It was a case-control study using observation. Consecutive COVID-19 patients who received a chest CT scan at hospital admission between October 1st, 2020, and April 31st, 2021 were identified. The accuracy of the Macklin effect in predicting spontaneous barotrauma was assessed in terms of sensitivity, specificity, positive (PPV), and negative predictive values (NPV).

During the research period, 981 COVID-19 patients obtained chest CT scans upon hospital arrival; 698 patients exhibited radiological evidence of interstitial pneumonia and were considered for further investigation. Macklin effect was observed in 33 (4.7%) of these patients, including all 32 patients who had barotrauma recently during their hospital stay (true positive rate: 96.9%); only 1/33 with the Macklin effect did not experience barotrauma (false positive rate: 3.1%). There were no barotrauma events observed in individuals who did not have the Macklin effect on their baseline chest CT scan. The Macklin effect predicted PMD/PNX with a sensitivity of 100% (95% CI: 89.1–100), specificity of 99.85% (95% CI: 99.2–100), PPV of 96.7% (95% CI: 80.8–99.5), NPV of 100%, and accuracy of 99.8% (95% CI: 99.2–100). Furthermore, all Macklin-positive patients developed ARDS that necessitated ICU hospitalization and, in 90.1% of instances, invasive mechanical ventilation. In COVID-19 patients, the Macklin effect predicts PMD/PNX with great accuracy; it is also a good predictor of disease severity. 

Reference:www.resmedjournal.com/article/S0954-6111(22)00118-4/fulltext