Thoracic surgical procedures in respiratory compromised patients supported by a pumpless interventional lung assist

Objective: Interventional lung assists (ILAs) are helpful in respiratory failure in ventilated patients. We evaluated the effectiveness of a novel interventional lung assist (novalung) to improve gas exchange in complex thoracic surgical procedures.

Methods: Ten patients underwent thoracic surgery with respiratory support by ILA. Indication for ILA application was the requirement for intraoperative prolonged discontinuation of ventilation (tracheal surgery and lung resections following pneumonectomy, n=6) or emergency procedures in patients with acute respiratory failure (n=4). The heparinized, pumpless extracorporal system was inserted percutaneously into the femoral blood vessels. Blood flow of the ILA, hemodynamics (cardiac output), and gas exchange were monitored.

Results: All procedures were performed successfully. Mean blood flow of the ILA was 1.58±0.3 (1.2–2.2) liter/min. Patients responded with a 15–25% increase in measured cardiac output to the onset of extracorporal circulation and low dose noradrenalin was required in 8 of 10 patients to maintain sufficient blood pressures. There was a moderate improvement in oxygenation (49ml/min transfer of O2) and a very efficient elimination of carbondioxid (211ml/min transfer of CO2). The device allowed for extended periods of apnoic oxygenation with discontinuation of ventilation, for up to 1 hour (mean 48min). Four patients with severe respiratory insufficiency were continued postoperatively on the device for a mean of 6.8 days (1–11 days).

Conclusions: The application of a pumpless interventional lung assist (ILA) was hemodynamically well tolerated and allowed for safe procedures in respiratory compromised patients, avoiding application of cardio-pulmonary bypass.