The objective of this randomized study is to compare the effect of two controlled chest tube protocols on the duration of air leak and fluid drainage following pulmonary lobectomy or segmentectomy by using an electronic regulated chest drainage system (Thopaz). Previous studies have suggested that the amount of negative pressure used at the level of the chest drainage device may affect the duration of air leak, but the results have been inconsistent, however as revealed in more recent studies understanding of the physics of chest drainage devices may have been confounded by lack of regulation of the pleural pressure.

In addition, experimental studies have shown that fluid drainage may be affected by the degree of negative pleural pressure applied.

Inclusion Criteria:

• Able and willing to read, understand, and provide written Informed Consent;
• Age range of 18-90 years;
• Patients submitted to lobectomy, segmentectomy and bilobectomy due to lung cancer or other intrathoracic lesions. Both open and minimally invasive (thoracoscopic) resections are acceptable.

Exclusion Criteria:

• if patients are submitted to lung resection associated with chest wall resection or diaphragm resection the patient will be excluded from analysis
• If during the postoperative hospital course there is a need for postoperative mechanical ventilation or hemodynamic instability the patient will be excluded from analysis.
• If the subject meets all of the inclusion criteria and none of the exclusion criteria, he/she is eligible to participate in the study.