Thursday, October 23, 2025

Understanding MARCH - Preventing Hypothermia & Managing Head Injuries


From the MARCH Mnemonic Series – Tactical Trauma Care for EMS Providers

Preserve and Protect After Stabilization

The final step in the MARCH sequence - Hypothermia Head Injury - focuses on two conditions that can rapidly worsen outcomes if not addressed early. 

After bleeding is controlled, the airway secured, respiration managed, and circulation assessed, providers must work to preserve core body temperature and protect neurological function.

Uncontrolled heat loss accelerates shock, impairs clotting, and undermines every prior intervention. Likewise, traumatic brain injury can progress quickly without vigilant monitoring and early management. 

Protecting a patient from heat loss and preserving the brain is essential for preventing secondary injury and supporting long-term survival and neurological recovery.

Image retrieved from tccc.org.ua

H – Hypothermia

Trauma-induced hypothermia is a major contributor to mortality in both military and civilian trauma.

Even in warm climates, a patient can quickly lose body heat through evaporation, convection, and exposure.

Hypothermia worsens the “lethal triad” of trauma - acidosis, coagulopathy & hypothermia - impairing clotting and promoting continued bleeding.

Image retrieved from tccc.org.ua

Recognition of Hypothermia

Look for early indicators, especially when there is significant blood loss or environmental exposure:

  • Shivering or muscle tremors (may disappear as hypothermia worsens)
  • Pale, cool, or mottled skin
  • Slurred speech or confusion
  • Slowed respirations or heart rate
  • Core temperature below 95°F (35°C)

Environmental factors such as wind, wet clothing, cold ground, or prolonged evacuation time accelerate heat loss, even in mild weather.

Image retrieved from tccc.org.ua

Hypothermia Prevention and Management

  • Remove wet clothing when tactically feasible and replace with dry layers.
  • Insulate from the ground using a poncho, sleeping pad, or casualty blanket.
  • Cover the casualty completely, including the head, to reduce radiant heat loss.
  • Use hypothermia prevention kits (e.g., Blizzard Survival Blanket, Ready-Heat™ Active Warming Blanket) if available.
  • Warm IV fluids or blood products when resources allow.
  • Monitor core temperature if devices are available, especially in prolonged field care scenarios.

Image retrieved from tccc.org.ua

Key Point: Preventing heat loss is just as vital as stopping bleeding - once the casualty is cold, outcomes worsen rapidly.

Image retrieved from tccc.org.ua

H – Head Injury

The “H” in MARCH also stands for Head Injury, emphasizing early recognition and management of traumatic brain injury (TBI), a leading cause of preventable death and long-term disability in prehospital trauma.

Image retrieved from tccc.org.ua

Recognizing Head Trauma

Watch for the following signs and symptoms:

  • Decreasing level of consciousness or responsiveness
  • Unequal or dilated pupils
  • Repetitive questioning, confusion, or agitation
  • Persistent vomiting or seizures
  • Irregular breathing patterns (Cheyne-Stokes or slow respirations)
  • Obvious penetrating or blunt trauma to the skull or face

Image retrieved from tccc.org.ua

Management Principles

  • Maintain airway and oxygenation. Keep SpO₂ > 90% and avoid hypoxia, which worsens secondary brain injury.
  • Prevent hypotension. Maintain systolic BP ≥ 90 mmHg to ensure cerebral perfusion.
  • Positioning: If spinal injury is not suspected, elevate the head 30° to promote venous drainage.
  • Avoid hyperventilation unless there are signs of herniation (e.g., blown pupil, rapid deterioration).
  • Control external bleeding with gentle pressure; do not compress depressed skull fractures or insert dressings into open cranial wounds.
  • Monitor for changes in mental status using tools like AVPU or GCS if time and environment allow.

In the tactical environment: head injuries often coexist with blast or penetrating trauma. Managing hypoxia and hypotension early has been shown to double the odds of survival in severe TBI (Eastridge et al., 2012).

Image retrieved from tccc.org.ua

Key Takeaway for EMS and Tactical Providers

The 'H' in MARCH is about preservation and protection - maintaining the physiological stability of a casualty who has already survived the most immediate threats. 

Hypothermia prevention and head injury management require vigilance, insulation, and gentle handling. In tactical medicine, saving a life doesn’t end with hemorrhage control, it continues with keeping that life viable during evacuation.

In short: preserve the heat, protect the brain

Image retrieved from tccc.org.ua

Conclusion of the MARCH Series

The MARCH sequence - Massive Hemorrhage, Airway, Respiration, Circulation, and Hypothermia/Head Injury - originated in Tactical Combat Casualty Care and remains the foundation of modern field trauma management. 

This structured approach guides responders to address the most preventable causes of death in the order they matter most. In this series, each component of MARCH is explored in turn, offering practical guidance for EMS and tactical providers operating in dynamic, resource-limited environments. 

From controlling catastrophic bleeding to protecting core temperature and neurological function, the series outlines a clear, evidence-informed pathway for stabilizing trauma patients and improving survivability in the prehospital setting. 

Train Hard. Stay Prepared. Save Lives.

Further Reading:

American College of Surgeons Committee on Trauma. (2022) Advanced Trauma Life Support (10th Ed). Chicago, IL: American College of Surgeons.

Bledsoe, B. E., Cherry, R. A. & Porter, R. S (2023) Paramedic Care: Principles and Practice (6th Ed) Boston, MA: Pearson Education

Butler, F. K. (2017) Tactical Combat Casualty Care: Beginnings. Wilderness & Environmental Medicine 28 (2S): S12-S17. 
Retrieved from https://pubmed.ncbi.nlm.nih.gov/28284483/ on October 8, 2025

Butler, F. K., Bennett, B., & Wedmore, C. I. (2017) Tactical Combat Casualty Care and Wilderness Medicine: Advancing Trauma Care in Austere Environments. Emergency Medicine Clinics of North America 35 (2): 391-407. Retrieved from https://pubmed.ncbi.nlm.nih.gov/28411934/ on October 8, 2025

Committee on Tactical Combat Casualty Care (2023) Tactical Combat Casualty Care (TCCC) Guidelines for Medical Personnel. Defense Health Agency, Joint Trauma System. Retrieved from https://jts.health.mil on October 8. 2025

National Association of Emergency Medical Technicians NAEMT (2020) TECCTactical Emergency Casualty Care Course Book (2nd Ed). Burlington, MA: Jones & Bartlett Learning

National Association of Emergency Medical Technicians NAEMT (2023) Tactical Emergency Casualty Care (TECC) Guidelines. NAEMT Education Division

National Association of Emergency Medical Technicians NAEMT (2025) 
PHTLS: Prehospital Trauma Life Support, Military Edition eBook (10th Ed). Burlington, MA: Jones & Bartlett Learning

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