Management of Gunshot Wound Patients in Hypovolemic Shock
Patients with gunshot wounds presenting with hypovolemic shock require immediate bleeding control procedures unless initial resuscitation measures are successful. 1
Initial Assessment and Classification
- Assess the extent of traumatic hemorrhage using established grading systems such as the ATLS classification of blood loss severity 1
- Classify shock severity based on blood loss parameters:
- Class I: <750 ml (15% blood volume), HR <100, normal BP
- Class II: 750-1500 ml (15-30%), HR 100-120, normal BP
- Class III: 1500-2000 ml (30-40%), HR 120-140, decreased BP
- Class IV: >2000 ml (>40%), HR >140, decreased BP 1
- Evaluate response to initial fluid resuscitation:
- Rapid response: Return to normal vital signs, minimal blood loss (10-20%)
- Transient response: Temporary improvement followed by deterioration, moderate ongoing blood loss (20-40%)
- Minimal/no response: Persistently abnormal vital signs, severe blood loss (>40%) 1
Immediate Interventions
Bleeding Control
- Identify the source of bleeding immediately through clinical assessment 1
- Patients with hemorrhagic shock and identified bleeding source should undergo immediate bleeding control procedure 1
- For unidentified bleeding sources, perform urgent clinical assessment of chest, abdomen, and pelvic ring stability 1
- Use early focused sonography (FAST) to detect free intraabdominal fluid 1
- Patients with significant free intraabdominal fluid and hemodynamic instability require urgent surgery 1
Fluid Resuscitation
- Begin crystalloid fluid therapy immediately for the hypotensive bleeding trauma patient 1
- Target systolic blood pressure of 80-100 mmHg until major bleeding is controlled (permissive hypotension) 1
- For rapid volume replacement:
Damage Control Surgery
- Employ damage control surgery in severely injured patients with:
- Deep hemorrhagic shock
- Signs of ongoing bleeding and coagulopathy
- Hypothermia and acidosis
- Inaccessible major anatomic injury
- Need for time-consuming procedures 1
Vasopressors and Inotropic Agents
- For patients with persistent hypotension despite adequate fluid resuscitation, consider norepinephrine 1
- Norepinephrine dosing:
- Dilute 4 mg (4 mL) in 1000 mL of 5% dextrose solution (resulting in 4 mcg/mL) 4
- Initial dose: 2-3 mL/min (8-12 mcg/min) 4
- Adjust rate to maintain systolic BP 80-100 mmHg 1, 4
- Average maintenance dose: 0.5-1 mL/min (2-4 mcg/min) 4
- Administer through a large vein, preferably an antecubital vein 4
- Monitor blood pressure every 2 minutes until desired BP is achieved, then every 5 minutes 4
Additional Management Considerations
- Avoid hyperventilation or excessive positive end-expiratory pressure in severely hypovolemic patients 1
- For pelvic ring disruption with hemorrhagic shock, perform immediate pelvic ring closure and stabilization 1
- Consider antifibrinolytic agents:
- Tranexamic acid: 10-15 mg/kg followed by infusion of 1-5 mg/kg/h 1
- Prevent hypothermia, which worsens coagulopathy 5
- For ongoing hemodynamic instability despite pelvic ring stabilization, consider angiographic embolization or surgical bleeding control 1
Pitfalls and Caveats
- Avoid excessive crystalloid administration, which can worsen coagulopathy and lead to abdominal compartment syndrome 1
- Monitor for extravasation of norepinephrine into tissues, which can cause local necrosis 4
- Avoid administering norepinephrine into leg veins in elderly patients or those with occlusive vascular diseases 4
- Do not delay transfer to surgical facility when evacuation time is short (<1 hour) - secure airway and breathing, then "scoop and run" 6
- Avoid hypertonic solutions in patients with severe head trauma 1