[Pulmonary complications after extracorporeal circulation. ECC lung syndrome]

Area of Science:

• Cardiology
• Pulmonary Medicine
• Critical Care Medicine

Background:

• Pulmonary complications are common after cardiac surgery requiring extracorporeal circulation (ECC).
• Despite advances in cardiorespiratory support, lung injury remains a significant concern.
• The study investigates the impact of ECC on lung function and structure.

Purpose of the Study:

• To analyze the clinical and radiological effects of ECC on the lungs in patients undergoing coronary revascularization.
• To investigate the occurrence of shunt syndrome and its relation to gas exchange abnormalities.
• To identify factors contributing to post-operative hypoxemia.

Main Methods:

• Clinical and radiological assessment of 40 patients undergoing coronary revascularization with ECC.
• Simultaneous analysis of arterial, mixed venous, and alveolar blood gases in 20 patients.
• Examination of 46 pulmonary biopsies using electron microscopy.
• Pulmonary artery catheterization in 35 patients to monitor hemodynamic variations.

Main Results:

• A consistent shunt syndrome was observed in patients, characterized by hypocapnia, hypoxemia, and increased alveolar-arterial oxygen gradient.
• Pleurotomy was the only studied variable significantly associated with increased hypoxemia.
• Electron microscopy revealed increased capillary permeability and destruction of interstitial and epithelial tissues.
• Membrane oxygenators showed potential in preventing some alveolar lesions.

Conclusions:

• Extracorporeal circulation-induced lung injury, or "ECC lung," is a significant cause of refractory hypoxemia post-cardiac surgery.
• Understanding the mechanisms of lung injury during ECC is crucial for improving patient outcomes.
• Further research into protective strategies, such as optimizing oxygenator use, is warranted.