Mark Tozer, PhD

Tuesday, October 21, 2025

Understanding MARCH - The Role of Circulation

Image retrieved from tccc.org.ua

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

After addressing massive hemorrhage, airway, and respiration, the next priority is Circulation, the body’s ability to deliver oxygenated blood to vital organs and tissues.

In trauma, the circulatory system can be compromised by shock, internal bleeding, or poor perfusion, even when obvious external hemorrhage has already been controlled.

Within the tactical environment, circulation assessment focuses on recognition and management of shock, maintaining perfusion, and preventing secondary injury. The goal is to identify subtle but deadly deterioration before it progresses beyond recovery.

C – Circulation

In tactical casualty care, circulation assessment differs slightly from the traditional EMS approach. The emphasis is on speed, simplicity, and practicality in resource-limited or high-threat conditions.

Blood pressure cuffs and monitors may not be available, so providers rely on physical signs and simple indicators to evaluate perfusion. The presence of a radial pulse and normal mental status are key field markers of adequate circulation.

Principles of Circulatory Assessment and Management

1. Check for Pulse and Perfusion

Radial Pulse: Presence suggests systolic blood pressure above roughly 80 mmHg, generally adequate for perfusion in tactical settings.

Weak or Absent Pulse: May indicate hypovolemia or shock; assess for additional signs of poor perfusion such as pallor, clammy skin, or delayed capillary refill.

Mental Status: A sudden change in consciousness (e.g., confusion, lethargy) is often an early sign of inadequate cerebral perfusion.

Remember: weak radial pulse + altered mental status = shock until proven otherwise.

Image retrieved from tccc.org.ua

2. Identify and Manage Non–Life-Threatening Bleeding

Once major bleeding has been controlled, systematically check for and address secondary bleeding sites that may have been overlooked during the initial MARCH sequence.

Apply direct pressure, pressure dressings, or hemostatic agents as needed.

Image retrieved from tccc.org.ua

3. Treat for Shock

Shock - a state of inadequate tissue perfusion - can occur from blood loss (hypovolemic), cardiac injury, or tension pneumothorax.

In tactical medicine, hemorrhagic shock is the most common.

Lay the casualty supine, if tactical conditions allow.

Keep the patient warm, hypothermia worsens coagulopathy and shock (addressed further in Part Five).

Provide fluids only when indicated by TCCC or TECC guidelines

If in shock (weak/absent radial pulse or altered mental status):

Administer whole blood if available; otherwise, 1:1:1 blood component therapy (plasma, platelets, red cells).

If blood products are unavailable, give Hextend or Lactated Ringer’s solution, titrating only to restore a palpable radial pulse or improved mental status (per TCCC guidance).

If the casualty is not in shock and has a palpable radial pulse and normal mental status: no IV/IO fluids are indicated.

Avoid over-resuscitation, too much fluid can dislodge clots and worsen bleeding.

4. Establish IV/IO Access When Appropriate

In tactical field care, IV or intraosseous access is indicated for:

Fluid resuscitation in shock
Medication administration (e.g., analgesics, antibiotics, TXA).

If available, administer Tranexamic Acid (TXA) within three hours of injury for casualties at risk of significant hemorrhage. Early TXA administration has been shown to reduce mortality from bleeding.

5. Continuous Reassessment

Circulation is dynamic, especially in prolonged field care or delayed evacuation.

Regularly recheck:
Pulse quality and rate
Mental status
Skin color, temperature, and moisture
Wound sites for renewed bleeding

Document all findings and interventions clearly for handoff to the next echelon of care.

Image retrieved from tccc.org.ua

Key Takeaway for EMS and Tactical Providers

Circulation management is about detecting shock early, maintaining perfusion, and preventing deterioration.

In the tactical environment, sophisticated monitoring tools are often unavailable, but trained observation remains powerful.

The provider’s mindset should be:

Feel for the pulse, read the patient, and keep the blood where it belongs.

Image retrieved from tccc.org.ua

Coming Up Next: Part Five – Hypothermia and Head Injury

The final step in the MARCH sequence focuses on protecting what you’ve fought to preserve, preventing hypothermia and managing head injuries to maintain survivability after initial stabilization.

In Part Five, we’ll discuss how temperature control, positioning, and neurologic assessment all play critical roles in keeping your casualty alive until evacuation and definitive care.

Because in tactical medicine, saving a life isn’t just about stopping the bleeding—it’s about keeping that life sustained.

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) TECC: Tactical 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

Sunday, October 19, 2025

Understanding MARCH - The Relevance of Respiratory Assessment

Image retrieved from tccc.org.ua
From the MARCH Mnemonic Series – Tactical Trauma Care for EMS Providers

After controlling massive hemorrhage and ensuring a patent airway, the next priority in the MARCH sequence is Respiration.

Effective breathing is critical for oxygen delivery and carbon dioxide removal. When trauma impairs the chest wall or lungs, hypoxia and shock can develop rapidly - even when the airway is clear.

In tactical or prehospital settings, respiratory compromise is often caused by thoracic injury, such as a gunshot, stab wound, or blast trauma.

These injuries can lead to life-threatening conditions like tension pneumothorax or open chest wounds, both of which are preventable causes of death when identified and treated early.

This article - the third in a five-part series - will focus on that next critical step:

R – Respiration

Respiration refers to the body’s ability to move air into and out of the lungs and to exchange gases at the alveolar level.

Any disruption - mechanical, anatomical, or physiological - can cause hypoxia and threaten survival.

The responder’s task is to rapidly assess, seal, decompress, and support breathing as needed.

Image retrieved from tccc.org.ua

Principles of Respiratory Management

1. Assess the Casualty’s Breathing

Begin by evaluating rate, depth, and effort of respirations. Look, listen, and feel for:

Asymmetrical chest rise or movement

Difficulty speaking, gasping, or labored breathing

Cyanosis around lips or fingertips

Tracheal deviation, jugular venous distention, or subcutaneous emphysema

Penetrating trauma to the chest or upper abdomen

If you’re operating in a tactical environment, conduct this assessment as efficiently as safety allows—rapid but systematic.

2. Expose and Inspect for Chest Injuries

Visually inspect the anterior, lateral, and posterior thorax for entry and exit wounds, contusions, or deformities. In low-light or confined spaces, gloved hands may detect what the eyes can’t.

Sucking chest wounds (open pneumothorax) occur when air enters the pleural space through a chest wall defect.

These must be sealed immediately with a vented or occlusive chest seal to prevent the progression to tension pneumothorax.

Modern products like the HyFin® Vent Chest Seal or FoxSeal™ are designed for field reliability and are standard in most tactical trauma kits.

Image retrieved from tccc.org.ua

3. Manage a Tension Pneumothorax

A tension pneumothorax occurs when air becomes trapped in the pleural space and cannot escape, collapsing the lung and compressing the heart and great vessels.
Signs may include:

Severe respiratory distress

Decreased or absent breath sounds on one side

Hypotension and tachycardia

Tracheal deviation (a late sign)

Image retrieved from tccc.org.ua

Intervention:

If tension pneumothorax is suspected and equipment/training allow, perform needle decompression:

Use a 14-gauge, 3.25-inch (8.25 cm) needle or catheter.

Insert into the 5th intercostal space, anterior axillary line (or 2nd intercostal space, midclavicular line if indicated).

Listen for escaping air and observe for improvement in breathing and perfusion.

Always reassess, if symptoms recur, repeat decompression or prepare for chest tube insertion at higher care levels.

Image retrieved from tccc.org.ua

4. Support Oxygenation and Ventilation

If available and appropriate, administer supplemental oxygen to maintain SpO₂ above 94%.

For inadequate respirations, assist with bag-valve-mask (BVM) ventilation while maintaining airway alignment. In prolonged field care, consider monitoring SpO₂ and ETCO₂, if resources allow, to guide ongoing management.

5. Continue Monitoring and Reassessment

The chest is dynamic, bleeding, air leakage, or mechanical disruption can recur with movement or time. Reassess chest rise, breath sounds, and patient condition frequently during evacuation.

Key Takeaway for EMS and Tactical Providers

Thoracic trauma demands vigilance. While hemorrhage and airway compromise often draw attention first, unrecognized respiratory failure can kill just as quickly. The tactical provider must be proficient in identifying chest injuries, applying chest seals, and performing needle decompression when indicated.

In short: find the holes, seal the leaks, relieve the pressure, and keep the oxygen moving.

Coming Up Next: Part Four – Circulation

Once bleeding is controlled, the airway is secure, and breathing is restored, it’s time to assess circulation—the body’s ability to perfuse vital organs.

In Part Four of our MARCH series, we’ll explore recognition and management of shock, fluid resuscitation strategies, and maintaining perfusion in both field and tactical environments.

Because after oxygen, the mission is to keep it flowing where it matters most.

Friday, October 17, 2025

Understanding MARCH - The Importance of Airway Management

Image retrieved from tccc.org.ua

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

Following the control of massive hemorrhage, the next lifesaving priority in the MARCH algorithm is Airway.

Without a patent airway, oxygen cannot reach the lungs, and death from hypoxia can occur within minutes.

While exsanguination kills fastest, airway obstruction follows closely - especially in cases of head or neck trauma, decreased consciousness, or maxillofacial injury.

In tactical environments, airway management must be both rapid and situationally appropriate. Providers balance lifesaving intervention with operational safety - sometimes working under fire or in low-light, resource-limited conditions.

This article - the second in a five-part series - will focus on that next critical step:

A – Airway Management

A patent airway is one that is open and unobstructed, allowing air to move freely in and out of the lungs. Even a partial obstruction can reduce oxygen delivery and lead to hypoxia, brain injury, or cardiac arrest.

According to the National Safety Council (2023), foreign-body airway obstruction remains the fourth leading cause of unintentional death in the United States - emphasizing the universal need for early recognition and decisive management.

Image retrieved from tccc.org.ua

Principles of Airway Management

1. Assess the Airway Early

Assessment begins with observing the casualty’s level of consciousness, respiratory effort, and ability to speak or make sounds.

The simple question, “Can the patient talk?” remains one of the fastest airway assessments available.

Look and listen for:

Gurgling, snoring, or stridor
Facial or neck trauma
Blood, vomitus, or foreign bodies in the mouth
Absent or inadequate respiratory effort

In tactical settings, assessment must be efficient and, if under threat, may need to wait until the situation is secure enough to act safely.

Image retrieved from tccc.org.ua

2. Basic Airway Maneuvers

If the airway is obstructed or compromised, begin with manual positioning techniques:

- Head-Tilt/Chin-Lift: For non-trauma patients who are unconscious and without suspected spinal injury.

- Jaw-Thrust: For trauma patients or when spinal injury cannot be ruled out.

- Recovery Position: For semi-conscious patients who can maintain their own airway but may vomit.

These simple maneuvers are often enough to restore airway patency temporarily and can be performed quickly even under fire or during evacuation.

Image retrieved from tccc.org.ua

3. Airway Adjuncts

When manual techniques are insufficient, adjunctive devices can maintain airway patency:

- Nasopharyngeal Airway (NPA): Preferred in tactical and field care. Well tolerated in conscious or semiconscious patients and effective even with facial injuries (unless contraindicated by basilar skull fracture).

- Oropharyngeal Airway (OPA): Used only in unconscious patients without a gag reflex. Easy to insert and effective when bag-valve-mask (BVM) ventilation is required.

Advanced airways (e.g., supraglottic devices, endotracheal intubation, or surgical cricothyrotomy) may be indicated in prolonged field care or when BVM ventilation fails, but such interventions should align with provider scope and environment.

4. Clear and Control the Airway

If obstruction is caused by a foreign body, blood, or vomitus, clear it quickly:

- Perform the abdominal thrusts in conscious choking patients.

- Use suction, if available, to remove debris or fluids.

- If foreign-body airway obstruction persists in an unresponsive patient, begin CPR following standard resuscitation protocols.

In tactical contexts, effective airway control often means doing the basics well—not overcomplicating care but ensuring the airway remains open during extraction and evacuation.

5. Ongoing Monitoring and Reassessment

Airway status can change rapidly. A casualty who was breathing adequately moments ago may deteriorate due to swelling, bleeding, or decreased consciousness.

Reassess frequently- especially after movement or as the tactical situation changes.

Key Takeaway for EMS and Tactical Providers

Airway management is the second priority in the MARCH sequence, but it’s equally vital to survival. The tactical provider’s goal is to establish and maintain a patent airway using the simplest effective method appropriate to the situation.

In many cases, that means manual maneuvers and an NPA—reserving advanced interventions for when time, equipment, and safety allow.

In every case, the principle remains: “Keep it open, keep it simple, keep reassessing.”

Coming Up Next: Part Three – Respiration

With bleeding controlled and the airway secured, attention turns to respiration—assessing and managing chest injuries that can silently compromise ventilation and oxygenation.

Part Three of our MARCH series will explore the recognition and treatment of life-threatening thoracic trauma, including tension pneumothorax and open chest wounds.

When the airway is open but the chest can’t move air, the mission shifts to restoring the breath.