Pulmonary Disease clinical trials at UCSD

Patients in end-stage cardiac failure and/or respiratory failure may be started on a rescue therapy known as Extracorporeal Membrane Oxygenation (ECMO). One of the major clinical questions is how to manage the ventilator when patients are on ECMO therapy. Ventilator Induced Lung Injury (VILI) can result from aggressive ventilation of the lung during critical illness. VILI and lung injury such as Acute Respiratory Distress Syndrome (ARDS) can further increase the total body inflammation and stress, this is known as biotrauma. Biotrauma is one of the mechanisms that causes multi-organ failure in critically ill patients. One advantage of ECMO is the ability to greatly reduce the use of the ventilator and thus VILI by taking control of the patient's oxygenation and acid-base status. By minimizing VILI during ECMO we can reduce biotrauma and thus multi-organ failure. Since the optimal ventilator settings for ECMO patients are not known, we plan to study the impact of different ventilator settings during ECMO on patient's physiology and biomarkers of inflammation and injury.

Respiratory failure occurs when the lung fails to perform one or both of its roles in gas exchange; oxygenation and/or ventilation. Presentations of respiratory failure can be mild requiring supplemental oxygen via nasal cannula to more severe requiring invasive mechanical ventilation as see in acute respiratory distress syndrome (ARDS).It is important to provide supportive care through noninvasive respiratory support devices but also to minimize risk associated with those supportive devices such as ventilator induced lung injury (VILI) and/or patient self-inflicted lung injury (P-SILI). Central to risk minimization is decreasing mechanical stress and strain and optimizing transpulmonary pressure or the distending pressure across the lung, minimizing overdistention and collapse. Patient positioning impacts ventilation/perfusion and transpulmonary pressure. Electrical impedance tomography (EIT) is an emerging technology that offers a noninvasive, real-time, radiation free method to assess distribution of ventilation at the bedside. The investigators plan to obtain observational data regarding distribution of ventilation during routine standard of care in the ICU, with special emphasis on postural changes and effects of neuromuscular blockade, to provide insight into ventilation/perfusion matching, lung mechanics in respiratory failure, other pulmonary pathological processes.

Modern intensive care units (ICUs) are increasingly adopting newer modes of mechanical ventilation such as adaptive pressure control (APC) modes but there are limited data available regarding risks and benefits of newer modes versus traditional ventilation modes. APC can inadvertently deliver high tidal volumes, which maybe harmful. High tidal volumes may be unrecognized by the provider, due to the complexities of ventilator algorithms and patient interactions. The objective of this aim is to identify risk factors for excess tidal volumes in patients on adaptive pressure control.