Hemorrhagic Shock in Trauma

Classification of Hemorrhagic Shock

• Massive hemorrhage is the most common cause of shock in trauma patients and is second only to traumatic brain injury as the leading cause of death in trauma patients.¹
• Advanced Trauma Life Support®-10 has an updated classification for hemorrhagic shock that includes new categories for pulse pressure and base deficit (Table 1).²

Initial Assessment and Interventions

The initial management of trauma patients with hemorrhage should be focused on:

Control of Compressible or Extremity Bleeding (Stop the Bleed)

• Direct pressure can help control blood loss from compressible external wounds.
• Running and interrupted sutures help control sites of external bleeding if direct pressure is insufficient.
• Clamping blood vessels is an acceptable method of hemostasis if the bleeding vessels are visualized. Blind clamping of vessels should not be performed.¹
• Tourniquets may be used in cases of amputation or severe extremity injury. These are often released every 45 minutes to avoid prolonged limb ischemia.¹
• Pelvic stabilization is important for unstable pelvic fractures, which are associated with vascular injuries and massive hemorrhage. Pelvic stabilization can be achieved by either applying a circumferential pelvic binder or tying a sheet firmly around the pelvis.¹

Control of Noncompressible Bleeding

• Various modalities can be used to identify the source of internal bleeding and guide further management (Table 2).

Obtain Vascular Access

• Options for vascular access are listed in Table 3.

Restore Intravascular Volume

• Minimize the administration of intravenous crystalloids during the resuscitation of trauma patients and transfuse blood products as soon as available.
• If blood products are not immediately available, administration of 500 mL boluses of isotonic balanced crystalloids, such as lactated Ringer’s solution, may be considered.¹
• In patients requiring massive transfusion, crystalloid resuscitation in a ratio greater than 1.5:1 per unit of pRBC transfusion was independently associated with worse outcomes, including a 70% higher risk of multi-organ failure and over a two-fold higher risk of acute respiratory distress syndrome and abdominal compartment syndrome.³
• Administration of large volumes of crystalloids (more than 1.5L) has been shown to be an independent risk factor for mortality in trauma patients, especially in elderly patients.⁴
• Early use of vasopressors may be harmful in hemorrhagic shock. However, vasopressors may be useful in cases of hemorrhagic shock with spinal cord injury.¹ In spinal cord injury cases, norepinephrine is the preferred vasopressor.

Transfuse Blood Products

• If transfusions are indicated, blood products should be given as soon as possible to avoid hypotension and to minimize crystalloid administration.
• Transfuse packed red blood cells (pRBC), fresh frozen plasma (FFP), and platelets in a 1:1:1 ratio to avoid coagulopathy in damage control resuscitation.
• If using aphaeresis platelets, transfuse pRBC, FFP, and aphaeresis platelets in a 6:6:1 ratio.
• While using type and crossmatched blood products is ideal, they can require significant time to prepare. If necessary, type-specific blood or emergency-release blood can be used. Girls and women of childbearing age should be administered O-negative blood, while O-positive blood can be administered in all men and in women in whom childbearing is not a consideration.
• Low titer group O-negative whole blood can also be used if available.
• Thromboelastography (TEG), rotation thromboelastometry (ROTEM), or other point-of-care coagulation assessments should be used to guide trauma resuscitation.

Predicting the Need for Massive Transfusion Protocol (MTP)

• Massive transfusion is defined as transfusing 10 units pRBC over 24 hours.
• Early identification of the need for MTP is associated with improved outcomes.
• Identifying the need for MTP is often dependent on clinical judgment and aided by several scoring assessments (Table 4).¹

Management of Severe Ongoing Hemorrhage

• Avoid hypothermia and minimize coagulopathy risks
  • Increase the ambient temperature in the trauma bay
  • Cover the patient in warm blankets
  • Use warm IV fluids and blood products
• The patient’s hemodynamics, lactate, and other laboratory parameters should be continuously monitored to ensure adequate tissue perfusion (Table 5).
• Administration of tranexamic acid should be considered if the patient arrives within 3 hours of injury.¹

Reverse Anticoagulation

• In patients on anticoagulant therapy with life-threatening bleeding, reversal of anticoagulation should be considered (Table 6).