Role of pleural manometry and transthoracic ultrasonography to predict entrapped lung

Unexpandable lung is a complication by which the lung does not expand to the chest wall with pleural space drainage, which will result in adverse events or intervention failure if not well recognized prior to the intervention. This study aimed to assess the role of pleural manometry and transthoracic ultrasonography in predicting abnormal lung expansion during pleural drainage. This was a prospective observational analytical study involving 50 patients that aims to predict abnormal lung expansion during pleural drainage using pleural manometry and transthoracic ultrasound. Regarding pleural manometry (pleural elastance), all patients in the entrapped lung group (100%) had pleural elastance > 14.5 cmH2o/L, while in the non-entrapped lung group, all patients (100%) had pleural elastance ≤ 14.5 cmH2o/L. Regarding ultrasonography, pleural thickening > 0.5 cm was found in all patients with entrapped lung (100%) and 50% of patients with non-entrapped lung with statistically significant difference. In the entrapped lung group, 20%, 35%, and 45% of patients had simple, complex non-septated, and complex septated pleural effusion, respectively, while in the non-entrapped lung group, 63.35%, 33.33%, and 3.32% of patients had simple, complex non-septated, and complex septated effusion, respectively, with statistically significant difference (p-value 0.0005). Pleural manometry and transthoracic ultrasound can guide decision-making regarding the timing of pleural interventions and management of cases with entrapped lung.