Fluid management is a complex yet fundamental aspect in the care of patients undergoing cardiac surgery, and different to that for patients in general intensive care and other surgical specialties. The underlying cardiac disease and impaired cardiovascular reserve of patients in this high-risk population means that significant hemodynamic alterations can impact adversely on their short- and long-term outcomes. Volume replacement during and after cardiac surgery is not influenced by filling pressures in isolation, but requires a critical balance with vasomotor tone, fluid responsiveness and cardiac contractility. The timing, type, volume and monitoring of fluid administration are important considerations. So far, the evidence does not favor a specific choice of fluid therapy and none of the available fluid therapies has been assessed for comparative endothelial homeostatic potential. This leaves a significant knowledge gap and an incentive for researchers, clinicians and industry to design and test safer and more efficacious choices for clinical use.

In the USA, injury is the leading cause of death among individuals between the ages of 1 and 44 years, and the third leading cause of death overall. Approximately 20 to 40% of trauma deaths occurring after hospital admission are related to massive hemorrhage and are potentially preventable with rapid hemorrhage control and improved resuscitation techniques. Over the past decade, the treatment of this population has transitioned into a damage control strategy with the development of resuscitation strategies that emphasize permissive hypotension, limited crystalloid administration, early balanced blood product transfusion, and rapid hemorrhage control. This resuscitation approach initially attempts to replicate whole blood transfusion, utilizing an empiric 1:1:1 ratio of plasma:platelets:red blood cells, and then transitions, when bleeding slows, to a goal-directed approach to reverse coagulopathy based on viscoelastic assays. Traditional resuscitation strategies with crystalloid fluids are appropriate for the minimally injured patient who presents without shock or ongoing bleeding. This chapter focuses on the assessment and resuscitation of seriously injured trauma patients who present with ongoing blood loss and hemorrhagic shock.