Update on hemorrhagic shock

Abstract

Hemorrhagic shock is characterized by a decreased circulating blood volume that leads to an alteration of the venous return. The initial adaptative response relies on a central sympathetic activation in an attempt to distribute the residual blood volume to the protected organs (brain and heart). At the opposite, splanchnic as well as muscular and kidney vasculature beds are sacrificed during the ischemic period. Volume resuscitation is the first therapeutic measure to undertake, with a systolic arterial pressure target of 80–100 mmHg and a mean cerebral perfusion pressure of 65–70 mmHg in the case of an associated brain injury. Massive fluid resuscitation is associated with a significant morbidity. Some authors advocated the early use of vasopressors (norepinephrine) along with a controlled volume resuscitation. In the setting of moderate-volume resuscitation, the use of hypertonic saline solution is encouraged. Red blood cells should be transfused as soon as possible, especially when hemoglobinemia is < 7 g/dl. Fresh frozen plasma (FFP) should be used to maintain a prothrombin ratio > 40%. A transfusion strategy using FFP and red blood cells at a 1:1 ratio is recommended. Platelet concentrates are used to maintain a platelet count > 50 G/l and > 100 G/l when traumatic brain injuries are associated. Fibrinogen treatment should be considered and systematically administered when fibrinogen concentration is < 1.5 g/l. An adrenal insufficiency is frequent, and a stress dose of 200 mg/day of hydrocortisone decreases morbidity after a traumatic shock.