The present disclosure comprises a novel in-line digital device for use with conventional pleural drainage systems. The device is configured to provide real-time analysis of one or more pleural gases or environmental factors, utilizing sensors positioned within an in-line housing to quantify parameters such as carbon dioxide concentration, temperature, and humidity. These metrics are used to support clinical decision-making regarding the timing of chest tube removal. The device is designed to be universally compatible with existing analog pleural drainage systems.