Oxidative stress management during non-invasive ventilation in acute respiratory failure

Excerpt

Oxidative stress, the condition of imbalance between reactive oxygen species (ROS) and antioxidant defense systems, is closely associated with several chronic and acute disorders including the aging process [1‐4]. ROS are highly reactive molecules because of unpaired electrons in their structure and are produced by living organisms as a result of cellular metabolism [5‐8]. At low to moderate concentrations, they function in physiological cell processes, but at high concentrations they damage cell components, such as lipids, proteins, and DNA, and can also activate apoptotic signaling [9‐11]. In the past few years, the role of oxidative stress has been extensively investigated in chronic respiratory diseases, and, in this context, ROS production is considered the main mechanism through which oxygen toxicity occurs at the cellular level [12, 13]. In particular, during respiratory failure, the episodes of hypoxia–reoxygenation may play a key role in ROS generation and organ injury. In addition, the exposures to an elevated fraction of inspired oxygen can lead to oxidative stress, inflammation, endothelial cell injury, and increased capillary permeability and may adversely affect patient outcome [14]. Some researchers have suggested a role of non-invasive ventilation (NIV) in the reduction of oxidative damage by ameliorating gas exchanges, finally resulting in an increase in oxygen saturation [15]. In this setting, the use of continuous positive airway pressure (CPAP) has been shown to decrease cardiovascular events and mortality rate, reducing oxidative stress and improving endothelial dysfunction [15]. …