Flow Controlled Ventilation in Cardiac Surgery

Positive-Pressure Respiration Clinical Trial

Official title: Flow Controlled Ventilation Versus Pressure Controlled Ventilation in Cardiac Surgery After Cardiopulmonary Bypass Without Ventilation - a Prospective, Randomized Clinical Study

Status Completed

Clinical Trial Summary

This trial investigates effects of individualized (by compliance guided pressure settings) flow-controlled ventilation compared to best clinical practice pressure controlled ventilation in cardiac surgery requiring cardiopulmonary bypass.

Clinical Trial Description

The aim of the study is to investigate flow-controlled ventilation (FCV) during cardiac surgery requiring cardiopulmonary bypass. Previous preclinical trials have already shown improved oxygenation and CO2 removal within a significantly reduced respiratory minute volume as an expression of more efficient gas exchange with FCV compared to volume controlled ventilation (VCV). Preliminary data of our own animal study comparing individualized FCV by compliance guided pressure settings with state-of-the-art low tidal volume pressure controlled ventilation (PCV) confirmed previous findings with a significantly improved oxygenation by 20% while reducing respiratory minute volume. We therefore assume that FCV may be a more lung protective ventilation method.

Open heart surgery requires bridging of the heart and lung function with a cardiopulmonary bypass (CPB) performed by a heart-lung machine. During this time the lung is most frequently not ventilated at all and lies collapsed in the chest for several hours. After weaning from CPB, the lungs must be recruited and ensure sufficient gas exchange of the blood. Not surprisingly, the incidence of postoperative pulmonary complications (PPC) at 20-30% is comparatively high after cardiac surgery and is the leading cause of perioperative mortality. Based on previous trials we expect improved oxygenation and thus arterial partial pressure of oxygen (pO2) is the main primary outcome parameter of this study. Furthermore, we expect improved recruitment of lung tissue due to controlled expiratory flow in FCV without the need of recruitment maneuvers, which may cause deleterious effects on lung tissue. Thus, lung tissue aeration assessed by Hounsfield units analyses of a postoperative computed tomography will be a secondary outcome parameter. ;

Related Conditions & MeSH terms

• Positive-Pressure Respiration
• Respiration; Artificial

• NCT number: NCT04306757
• Study type: Interventional
• Source: Medical University Innsbruck
• Status: Completed
• Phase: N/A
• Start date: March 6, 2020
• Completion date: March 2, 2021