Hextend attenuates hypercoagulability after severe liver injury in swine

Hypercoagulability is a major source of morbidity and mortality after injury. A resuscitation regimen that modulates this coagulopathy may prove beneficial. We sought to evaluate the effects of lactated Ringer's (LR) solution and Hextend on the resuscitation of uncontrolled hemorrhagic shock.

Twenty swine underwent invasive line placement, midline celiotomy, and splenectomy. After a 15-minute stabilization period, we recorded a baseline mean arterial pressure and created a grade V liver injury. The animals bled freely for 30 minutes, after which we measured the initial blood loss (that after injury). We blindly randomized the swine to receive LR solution or Hextend to achieve and maintain the baseline mean arterial pressure for 90 minutes postinjury. Laboratory values were obtained at baseline and on completion of the 2-hour study period.

The initial blood loss (before resuscitation) was 22 mL/kg in both treatment groups (p = 0.97). Animals required 119 +/- 78 mL/kg of fluid in the LR group and 40 +/- 21 mL/kg in the Hextend group (p = 0.01). After resuscitation, the secondary blood loss was 3.7 +/- 1.7 mL/kg in the LR group and 4.7 +/- 1.1 mL/kg in the Hextend group (p = 0.1). Thrombelastography revealed a hypercoagulable state in all animals after injury. This was less pronounced in those animals resuscitated with Hextend. Routine tests of coagulation did not reveal a hypercoagulable state.

Modulation and restoration of normal coagulation is critical in the management of trauma patients. The patient's coagulation profile might determine the type of fluid to be used at various times during their course. Thrombelastography is superior to routine coagulation assays for the detection of a hypercoagulable state. Resuscitation with Hextend results in a decreased fluid requirement and attenuation of hypercoagulability after injury without increased blood loss.