Hemorrhagic Shock and Damage Control Resuscitation

By Jointra Editorial Team, Certified EMT

Hemorrhage: The Preventable Killer

Hemorrhage accounts for 30–40% of trauma deaths and is the leading cause of preventable death in both civilian trauma and military combat. The majority of these deaths occur in the first hour. What EMS does in that first hour — or fails to do — directly determines who survives.

Physiology of Hemorrhagic Shock

Blood loss triggers a cascade of compensatory mechanisms:

1. Increased heart rate — the first and most sensitive sign of volume loss 2. Vasoconstriction — blood shunted from skin, gut, and muscle to maintain core perfusion 3. Decreased urine output — kidneys conserving fluid 4. Eventually, hypotension — a late and ominous sign; usually means 30%+ blood volume lost

Classes of Hemorrhagic Shock

| Class | Blood Loss | HR | BP | Mental Status | |---|---|---|---|---| | I | <750mL (<15%) | <100 | Normal | Anxious | | II | 750–1500mL (15–30%) | 100–120 | Normal or ↓ | Anxious | | III | 1500–2000mL (30–40%) | 120–140 | ↓ | Confused | | IV | >2000mL (>40%) | >140 | ↓↓ | Lethargic/obtunded |

Tachycardia is the earliest sign. Do not wait for hypotension.

The Old Model: Crystalloid-First

For decades, the standard approach to hemorrhagic shock was aggressive IV crystalloid (normal saline or LR) resuscitation. Restore the volume, restore the pressure. This approach is now known to be harmful in hemorrhagic shock.

Why? Because:

• Crystalloids dilute clotting factors, worsening coagulopathy
• They cause cellular edema
• They may increase blood pressure enough to dislodge clots at injury sites (popping the clot)
• Large volumes cause hypothermia, acidosis, and the lethal triad

Damage Control Resuscitation (DCR)

The modern approach, developed from military trauma experience, has three pillars:

1. Hemorrhage control — first and always

• Direct pressure and wound packing (hemostatic gauze: Combat Gauze, Celox)
• Tourniquets for extremity hemorrhage (apply early, high and tight)
• Pelvic binder for pelvic ring fractures
• Needle decompression for tension pneumothorax

2. Permissive hypotension (in penetrating trauma)

• Target systolic BP 80–90 mmHg (MAP 50–65) until surgical hemorrhage control
• Exception: traumatic brain injury (TBI) — maintain SBP >110 mmHg
• Rationale: avoid popping clots while tolerating mild hypotension

3. Balanced blood product resuscitation

• Whole blood or 1:1:1 ratio of packed red cells : fresh frozen plasma : platelets
• Minimize crystalloid
• Tranexamic acid (TXA) 1g IV over 10 minutes within 3 hours of injury (reduces mortality in major trauma)

Transport Priority

Hemorrhagic shock patients need a trauma surgeon, not a pre-hospital provider. Scene time should be minimized. Control compressible hemorrhage, establish IV/IO access, and move. Definitive hemorrhage control is surgical.

"Stay and play" vs. "scoop and run" in penetrating trauma: transport wins.