We have improved on our system to provide demand cardiopulmonary assistance through peripheral cannulation alone, using an extracorporeal membrane lung perfusion system. The key to its success lies in the decompression of the left ventricle using a specially designed helical coil to render the tricuspid and pulmonary artery valves partially/totally incompetent; the gentle ventilation of the lungs with 5% of C02 in room air; the use of pul- satile blood flow; and the use of special blood catheters to allow high flow extracorporeal bypass through peripheral cannulation alone. We have greatly expanded our own understanding of the nature of acute lung failure secondary to the use of high tidal volumes, at high PIP. Depending on the respiratory rate, this evolving acute respiratory failure can rapidly transform a mild acute respiratory failure, into a sever ARDS, with multiorgan system failure that includes primary lung failure, and failure of the CNS, hepatic renal and the cardiocirculatory systems. The cardiocirculatory system failure does not lend to recovery by means now practiced in the clinical intensive care unit, or in the surgical research laboratory. To reduce our reliance on mechanical ventilators, we have developed a system to provide ventilation to an important anatomical structure that does not in and of itself directly participate in gas exchange, the trachea. We pass at a high flow humidified warm gas through a 1 mm catheter directly to the level of the carina. The trachea becomes thus well ventilated, and the effectiveness of spontaneous ventilation or the effectiveness of mechanical ventilation is thereby greatly enhanced. We have shown that this technique (ITV) can be successfully employed to sustain spontaneous ventilation (no mechanical ventilation) with as little as 6-12% of remaining normal lungs. Similarly, this technique can greatly improve on mechanical ventilation by allowing better alveolar ventilation at lower tidal volumes.
NIH ExPorter
NIH ExPorter