Evaluation of (Wet) and (Dry) Mediastinal Chest Drainage in Minimally Invasive and Conventional Cardiac Surgery

Background: Drainage of fluid and evacuation of air from the pericardial and pleural spaces after cardiothoracic surgery is necessary to prevent effusion, tamponade, and pneumothorax, and also to detect hemorrhage. For this purpose, negative-pressure drains are placed in the mediastinum and pleural cavities. We compared the efficacy and safety of two systems wet and dry drainage for the management and monitoring of negative pressure and anti-reflux valve safety systems, to promote healing of the pleural and pericardial cavities. Methods: Two devices for mediastinal chest drainage [Venice PAS (Wet) and Rome PAS (Dry); both Eurosets SRL, Medolla, Italy] were evaluated in terms of safety, efficacy and clinical outcomes in a cohort of 60 patients who underwent elective cardiac surgery procedures. The patients were divided into a minimally invasive cardiac surgery (MICS) group [n=30; mitral valve surgery (MVS) by right anterolateral mini-thoracotomy] and a conventional cardiac surgery (CCS) group [n=30; coronary arterial bypass grafting (CABG) in full sternotomy] at a single institution (Anthea Hospital GVM Care & Research, Bari, Italy). Results: Negative pressure was managed with a target value of -20 cmH2O measured in the chest tube and was related to the device: deviation of ± 1 cmH2O for the Venice PAS (Wet) and 0 cmH2O for the Rome PAS (Dry) in the MICS group; deviation of 1 ± 0.8 cmH2O for the Venice PAS (Wet) and 0.8±0.2 cmH2O for the Rome PAS (Dry) in the CCS group. A constant volumetric air leak meter (VALM) value and the absence of air-leak bubbling were correlated with the absence of air in the pleural cavity and complete pulmonary re-expansion to restore normal respiratory dynamics in the MICS group for both models of chest drainage. The maximum total pericardial blood drained was 1104 ± 302 ml with Venice PAS (Wet) and 1530 ± 230 with Rome PAS (Dry) in the CCS group. There were no reports of cardiac tamponade in either group. Conclusions: The two mediastinal chest drainage devices [Venice PAS (Wet) and Rome PAS (Dry)] in this study were effective, accurate for measuring the applied negative pressure, and safe in their application after cardiac surgery procedures via minimally invasive and conventional approaches for blood and liquid drainage, prevention of cardiac tamponade, and restoration of normal respiratory dynamics after surgical pneumothorax. Both systems are equipped with anti-reflux valves to prevent air and blood from entering the drainage, and no adverse events were reported.