Pathophysiology of Hemorrhagic Shock

Hemorrhage is a major cause of death in trauma patients. The medical definition of hemorrhagic shock is tissue hypoperfusion resulting from a reduction of blood volume. Decreased blood pressure resulting from acute blood loss induces cardiac stimulation, systemic vasoconstriction, and volume redistribution. These effects are due to the baroreceptor reflex, the humoral compensatory mechanisms including the renin angiotensin system, and the release of catecholamine and vasopressin. Hemorrhagic shock causes acidosis, hypothermia, and coagulopathy, known as ‘the lethal triad.’ Tissue hypoxia induces metabolic acidosis by producing lactic acid. The three components of the lethal triad amplify each other and form a vicious cycle, eventually causing the death of the patient. To reduce the risk of mortality in severely bleeding patients, we need to understand the pathophysiology of hemorrhagic shock and the related complications.

Early management of complication on severe multiple trauma / 中华急诊医学杂志

Objective To analyze the efficacy of early management of eomplications in patients with multi-ple traumas by applying the damage control theory. Method All total of 116 patients admitted to Wuhan Tongji Hospital between Jan 2006 and Jan 2008 were included in this retrospective study and were classified according to treatment method. Overall, 55 cases underwent damage control operations and 61 cases underwent conventional management. The groups of patients were compared in terms of parameters such as length of operation time, time to resuscitate from shock, lethal triad of death (LTD), complications and treatment outcomes after operation. Results The length of operation time was (67.43±19.52) min, resuscitation time from shock was (6.77±3.16) h and LTD was (11.54±4.10) h in the damage control group, and (163.95±55.41) min, (22.51±11.65) h and (34.55±5.63) h, respectively, in the conventional group, with significant differences between the two groups (P< 0.01). The per capita complication and mortality rates were 227.27 % and 3.64 %, respectively, in the dam-age control group and 363.93 % and 9.84%, respectively, in the conventional group (P <0.05). Couclusions Here, we demonstrated that early management of patients with multiple traumas undergoing operations by apply-ing the damage control theory significantly decreased the operation time, and decreased time to resuscitation from shock and LTD. Furthermore, this approach significantly reduced the incidence of comphcations and the mortality rate of patients with severe multiple traumas.