Damage control resuscitation decreases systemic inflammation after hemorrhage

Area of Science:

• Trauma and emergency medicine
• Immunology
• Physiology

Background:

• Severe hemorrhagic shock triggers systemic inflammation and organ damage.
• Transfusing plasma and packed red blood cells (pRBCs) is clinically supported for hemorrhagic shock.
• The impact of varying fresh blood product ratios on inflammation and organ injury remains unclear.

Purpose of the Study:

• To investigate the effects of different fresh plasma to pRBC ratios on systemic inflammation and organ injury following hemorrhagic shock.
• To determine the optimal ratio of plasma to pRBCs for resuscitation in a murine model.

Main Methods:

• Mice underwent induced hemorrhagic shock and were resuscitated with varying ratios of fresh plasma and pRBCs (plasma alone, pRBCs alone, 2:1, 1:1, 1:2).
• Biochemical and hematologic parameters, serum cytokine levels, tissue myeloperoxidase activity, and vascular permeability were assessed.
• Organ injury markers were evaluated in intestinal and lung tissues.

Main Results:

• Resuscitation with pRBCs alone increased hemoglobin but did not significantly alter other hematologic/biochemical parameters.
• Higher plasma:pRBC ratios (excluding 1:1) elevated pro-inflammatory cytokine concentrations (KC, MIP-1α, MIP-2) and myeloperoxidase levels in the gut and lungs.
• The 1:1 plasma:pRBC ratio significantly reduced intestinal and lung vascular permeability compared to other groups.

Conclusions:

• Resuscitation with a 1:1 ratio of fresh plasma to pRBCs effectively mitigates systemic inflammation and organ injury.
• These findings suggest that transfusing blood products in physiologic ratios, specifically 1:1, offers a potential advantage in treating severe hemorrhagic shock.