Hemorrhagic Shock Medical Slides

Present the lethal triad (vicious cycle of death): hypothermia (<35°C impairs coagulation factor function, platelet adhesion, and fibrinolysis), acidosis (pH <7.2 reduces coagulation factor activity by >50%, impairs cardiovascular response to catecholamines), and coagulopathy (consumption, dilution, and dysfunction). Each element worsens the others — hypothermia causes acidosis and coagulopathy, acidosis worsens coagulopathy and cardiac function. DCR directly targets all three: warm blood products and fluids, limit crystalloid (worsens all three), early hemostatic resuscitation, and expeditious surgical hemorrhage control.

Present the concept: target SBP 80-90 mmHg (MAP 50-60) in penetrating trauma until surgical hemorrhage control, avoiding aggressive fluid resuscitation that dislodges clots, dilutes clotting factors, and worsens hypothermia. Key evidence: Bickell 1994 (delayed resuscitation in penetrating trauma improved survival), PROPPR trial (balanced resuscitation), and military experience. Contraindications to permissive hypotension: TBI (needs CPP maintenance, target SBP >110 per Brain Trauma Foundation), spinal cord injury, and elderly patients with poor cardiovascular reserve. Duration should be minimized — this is a bridge to definitive hemorrhage control.

Present REBOA (Resuscitative Endovascular Balloon Occlusion of the Aorta): placed via femoral artery access, balloon inflated in Zone I (descending thoracic aorta, for abdominal/pelvic hemorrhage) or Zone III (infrarenal aorta, for pelvic/junctional hemorrhage). Serves as a bridge to definitive surgical control — increases proximal aortic pressure while reducing distal hemorrhage. AORTA registry data shows improved SBP but mixed mortality data. Complications: distal ischemia (limit inflation time), aortic injury, access site bleeding. Presented as an alternative to resuscitative thoracotomy with aortic cross-clamping in select patients.