Mitochondrial function and markers of oxidative stress in patients with organ failure

Multiple organ dysfunction syndrome (MODS) is the primary cause of mortality and morbidity in intensive care units. MODS is associated with common intensive care unit diseases such as severe sepsis, septic shock, hemorrhagic shock and severe acute pancreatitis. In MODS, despite adequate delivery of oxygen, cells are not able to use this oxygen. This phenomenon is called cytopathic hypoxia and is thought to be due to mitochondrial dysfunction (MD). In health, mitochondria utilise most of the oxygen delivered to cells to generate the energy currency of cells called adenine triphosphate. However, it is not known what happens to mitochondrial function as MODS progresses and whether mitochondrial function (MF) can predict severity of organ failure. It is also not known whether the pattern of MD is similar in diseases such as shock with sepsis, and shock without sepsis compared to healthy volunteers. This study will measure MF from peripheral blood at multiple time points from patients with shock with sepsis, shock without sepsis and healthy volunteers in order to answer these questions. Often, after many months after discharge from intensive care unit, patients continue to still feel fatigued, it is not known whether this fatigue has any correlation with MF. This study will also address this question.