MARCH is the assessment sequence at the heart of modern trauma care: Massive hemorrhage, Airway, Respiration, Circulation, Hypothermia. It is not a gear list or a certification — it is an order of operations, built on decades of casualty data showing which injuries kill fastest and which of those deaths are preventable. Learn the sequence and you have a mental checklist that works whether you are a combat medic, a patrol officer, or a parent who just witnessed a bad crash on the interstate. This is the hub of our MARCH deep-dive series; each letter below links to a full guide.

Where MARCH Comes From: TCCC

MARCH was developed inside Tactical Combat Casualty Care (TCCC), the U.S. military's trauma doctrine, maintained by the Committee on Tactical Combat Casualty Care (CoTCCC). The driving insight came from casualty analyses stretching back to Vietnam: the leading causes of preventable battlefield death were extremity hemorrhage, tension pneumothorax, and airway obstruction — in that order of lethality. Older frameworks like the ABCs (Airway, Breathing, Circulation) were designed for medical emergencies such as cardiac arrest; in penetrating trauma, a casualty can bleed out from a limb wound in minutes, long before an airway problem develops. MARCH reorders the priorities to match how trauma actually kills. Its civilian translation, TECC, kept the sequence intact — our TCCC vs. TECC comparison covers how the two protocols differ, and What Is TCCC? covers the phases of care around it.

M — Massive Hemorrhage

First priority: find and stop life-threatening bleeding. Arterial bleeding from an arm or leg can be fatal in as little as three to five minutes, which is why it outranks everything else. The tools are direct pressure, tourniquets for extremity wounds, and hemostatic or wound-packing gauze for junctional areas — groin, armpit, neck base — where a tourniquet cannot work. These are also the most learnable skills in all of trauma care, which is exactly what a Stop the Bleed course teaches. Read the full deep dive: M — Massive Hemorrhage: Tourniquets, Gauze & When to Use Each, and browse the matching Massive Hemorrhage Control collection.

A — Airway

Second: confirm the casualty can move air. In an unconscious person the most common obstruction is their own tongue and relaxed soft tissue, and the highest-value layperson intervention is simple positioning — the recovery position lets gravity keep the airway open and fluids draining out. The standard IFAK adjunct is the nasopharyngeal airway (NPA), a soft tube placed by trained responders to keep the passage open. Airway shares a deep dive with the next letter: A & R — Airway and Respiration.

R — Respiration

Third: check the chest. Penetrating chest trauma can break the mechanics of breathing — air enters through the wound, collapses the lung, and in the worst case builds into tension pneumothorax, where pressure compresses the heart itself. The field response is an occlusive chest seal over penetrating chest wounds (vented seals are the current TCCC preference), checking for exit wounds, and monitoring. Needle decompression, the definitive treatment for tension pneumothorax, is strictly a trained-provider intervention — the deep dive explains what it is and whose job it is. Full guide: A & R — Airway and Respiration; gear lives in the R — Respiration collection.

C — Circulation

Fourth: reassess bleeding control and support circulation. This means checking that tourniquets are still tight, reinforcing packed wounds with pressure dressings, and watching for the signs of shock — pale skin, rapid weak pulse, altered mental status. At the provider level this step includes IV access and fluid decisions; at the layperson level it is vigilance and pressure dressings done well. Full deep dive: C & H — Circulation and Hypothermia.

H — Hypothermia (and Head Injury)

Fifth: keep the casualty warm — always, even in summer. Blood loss wrecks the body's ability to regulate temperature, and hypothermia impairs clotting, which makes every bleeding problem worse. This vicious cycle (hypothermia, acidosis, coagulopathy) is called the lethal triad, and breaking it costs almost nothing: insulate the casualty from the ground, cover them with a blanket or hypothermia wrap, and protect them from wind and rain. Many curricula also fold head-injury awareness into H. Deep dive: C & H — Circulation and Hypothermia; see the Hypothermia & Head Injury collection for wraps and blankets.

After MARCH: PAWS-B

MARCH covers the life threats; the follow-on mnemonic PAWS-B covers the next tier of care once those are handled: Pain management, Antibiotics, Wounds (reassessment and dressing of everything non-life-threatening), Splinting, and Burns. Most of PAWS-B sits at the provider level, but it is worth knowing the shape of it — it explains why a well-built kit contains splints and dressings alongside the trauma items.

Why Laypeople Should Learn MARCH

Average EMS response time in the United States is seven to ten minutes — longer in rural areas — and the injuries at the top of MARCH can kill in three to five. The person who determines whether a casualty is alive when the ambulance arrives is usually whoever is already standing there. MARCH gives that person a sequence instead of panic: stop the worst bleeding, open the airway, seal the chest, maintain pressure, keep them warm. None of the layperson-level skills require a license, and all of them are taught in a weekend or less. Start with a Stop the Bleed course, then look at TECC-based training for the full sequence.

Putting MARCH in Your Pocket

Once you know the sequence, organize your gear around it — a kit staged in MARCH order is a kit you can navigate under stress. Our guide to building a MARCH-compliant IFAK from scratch walks the loadout letter by letter, or you can grab a pre-assembled kit from the stocked kits collection and inventory it yourself. Either way, add a set of MARCH quick-reference cards to the kit — under stress, a printed checklist beats memory.

Gear is not a substitute for training. The sequence you just read is the syllabus; a hands-on course is where it becomes a skill.

This article is for educational purposes only and is not medical advice; seek professional training and consult qualified medical professionals.