The MicroRESUS study: An observational study to examine the effects of circulatory shock and resuscitation on microcirculatory function and mitochondrial respiration after cardiovascular surgery.

Post-cardiotomy shock (PCS) occurs in up to 5% of cardiovascular surgeries and has an in-hospital mortality rate as high as 75%. Physiologic derangements are often multifactorial, including ischemic-reperfusion injury leading to low cardiac output, vasoplegia, hemorrhage, or pericardial tamponade. Resuscitation strategies often target the normalization of systemic hemodynamics, however, practices to achieve standard macrocirculatory goals often fail to reverse microcirculation abnormalities or address cytopathic hypoxia. Perioperative shock may be the result of an imbalance between oxygen delivery and oxygen demand or could be the result of impaired oxygen utilization. This study will examine differences in microcirculatory function and mitochondrial respiration in patients with circulatory shock after cardiovascular surgery.