Hypoxically stored RBC resuscitation in a rat model of traumatic brain injury and severe hemorrhagic shock.

This study aims to investigate the effects of hypoxically stored Red Blood Cells (RBCs) in a rat model of traumatic brain injury followed by severe hemorrhagic shock and resuscitation. RBCs were made hypoxic using an O2 depletion system (Hemanext Inc. Lexington, MA) and stored for 3 weeks. Experimental group animals underwent craniotomy and blunt brain injury followed by severe HS. Rats were resuscitated with either fresh RBCs (FRBCs), 3-week-old hypoxically stored RBCs (HRBCs), or 3-week-old conventionally stored RBCs (CRBCs). Resuscitation was provided via RBC transfusion equivalent to 70 % of the shed blood and animals were followed for 2 h. The control group was comprised of healthy animals that were not instrumented or injured. Post-resuscitation hemodynamics and lactate levels were improved with FRBCs and HRBCs, and markers of organ injury in the liver Aspartate aminotransferase (AST), lung (chemokine ligand 1- CXCL-1 and Leukocytes count), and heart (cardiac troponin, Interleukin- 6-IL-6 and chemokine (C-X-C motif) ligand 1 TNF-α) were lower with FRBC and HRBC resuscitation compared to CRBC. Following reperfusion, biomarkers for oxidative stress, lipid peroxidation, and RNA/DNA injury were assessed. Superoxide dismutase (SOD) levels in the HRBC group were similar to the FRBC group and levels in both groups were significantly higher than CRBCs. Catalase levels were not different than control values in the FRBC and HRBC groups but significantly lower with CRBCS. Thiobarbituric acid reactive substances (Tbars) levels were higher for both CRBCs and HRBCs. Hypoxically stored RBCs show few differences from fresh RBCs in resuscitation from TBI + HS and decreased organ injury and oxidative stress compared to conventionally stored RBCs.