Most trail first aid kits are assembled once, checked approximately never, and opened for the first time in conditions that are the opposite of ideal for learning. The result is a kit that is present but not functional — the right items are there, but the person holding them doesn’t know which problem each one solves or in what sequence to apply them.

This guide goes through each category of first aid kit item with the specific condition it addresses and the technique for using it correctly. It is not a substitute for a first aid course — it is the reference that makes the course knowledge stay accessible when you’re on a mountain with a bleeding knee and adrenaline in your system.

Before You Open the Kit: Assess First

The instinct on encountering an injured person is to open the first aid kit immediately. Resist it. The first aid kit addresses the injury after the assessment has determined what the injury is. Opening the kit before assessing wastes time and creates the false impression of purposeful action where there is none.

The primary survey — the first pass assessment — takes 60 seconds and addresses only life-threatening conditions in order of urgency:

• Airway: is the airway open? Tilt head back, lift chin. If unconscious and not breathing normally — begin CPR.
• Breathing: is the person breathing? Look for chest rise, listen, feel for breath on your cheek.
• Circulation / catastrophic bleeding: is there severe, life-threatening bleeding? Apply direct pressure immediately — before anything else in the kit.
• Disability: is the person conscious? Use AVPU (Alert, Voice, Pain, Unresponsive).

Only after completing this survey and addressing any life threats should you open the kit for detailed wound management.

Item by Item: What Each Thing Does

Sterile gauze pads

What they do: absorb blood and provide a clean contact surface for wounds. How to use: place directly over bleeding wound; apply firm direct pressure with your hand over the gauze; do not remove to check — add more gauze on top if blood soaks through. Gauze can also be used wet (with clean water) to clean a wound surface before dressing. Do not use: cotton wool directly on wounds — fibres shed into the wound and cause infection.

Wound closure strips (Steri-Strips)

What they do: hold the edges of a clean, shallow laceration together to promote healing and reduce scarring. How to use: dry the skin completely around the wound (not inside it); apply strips perpendicular to the wound line at 5mm intervals, beginning at the centre; bring edges together gently without tension; apply final strip parallel to the wound over the ends of the perpendicular strips to anchor them. Do not use on: contaminated wounds, deep wounds, or wounds on joints where movement will pull the strips open.

Non-adhesive dressings (Telfa pads)

What they do: cover wounds without sticking to the wound surface, allowing removal without reopening the wound. How to use: place shiny side down directly on the wound; secure with medical tape or a conforming bandage; change daily or when saturated. Non-adhesive dressings are the correct covering for any open wound, blister base, or abrasion — standard adhesive plasters stick to the wound bed and tear it open on removal.

Elastic conforming bandage (crepe bandage)

What it does: applies compression to reduce swelling; secures dressings on joints and limbs; supports sprains. How to use: begin below the wound/injury and work upward; apply with 50% overlap on each turn; firm but not constricting — check circulation after application (warm skin, pink nail beds, capillary refill under 2 seconds). For ankle sprains: figure-8 pattern (anchor below calf, cross over front of ankle, loop under foot, back over ankle in opposite direction, closing circles upward).

Medical tape (Leukopor, Micropore)

What it does: secures dressings; protects blister hotspots; anchors conforming bandages. How to use: apply to dry skin; tear against the roll rather than scissors for clean ends; Leukopor is skin-friendly for sensitive areas; zinc oxide tape (Leukotape) is more adhesive and better for high-friction areas and ankle taping. Keep one roll of each in the kit.

Irrigation syringe (10ml)

What it does: delivers pressurised water to flush debris from wounds — the most important single item for infection prevention on trail wounds. How to use: fill with clean water; hold the tip 2cm from the wound; depress plunger fully in one firm press; refill and repeat until the wound runs clear and is visually clean. This item is missing from most pre-packaged kits and should be added manually.

Compeed hydrocolloid blister plasters

What they do: provide cushioning over blister hotspots and formed blisters; absorb fluid from the blister base; reduce friction. How to use: apply to clean dry skin; mould to the contour of the foot; leave in place until it detaches naturally (usually 3–5 days) — removing Compeed early reopens the blister bed; apply over intact blisters and over formed blisters after draining.

SAM splint (malleable aluminium and foam)

What it does: immobilises injured limbs in a position of comfort for evacuation. How to use: mould the splint to the desired shape before applying; pad bony prominences (ankle, wrist, elbow) with gauze; apply splint and secure with conforming bandage; check circulation after application. A SAM splint can be formed into wrist, ankle, or straight-leg configurations from a single 91cm strip. Standard trekking poles as improvised splints work for longer-bone injuries when a SAM splint is not available.

Medications: What to Carry and When to Use Them

Kit Maintenance: The Pre-Trip Checklist

A first aid kit checked once on purchase and never again will fail when needed. Before every multi-day trek and at the start of each season:

• Check expiry dates on all medications and sterile items — expired sterile packaging is no longer sterile
• Restock any items used on the previous trip — the item most often missing is the one that was used and not replaced
• Verify the irrigation syringe is present and working — this is the item most commonly omitted from pre-packaged kits
• Check that Compeed, Steri-Strips and tape have not dried out or lost adhesion — store kits away from direct heat
• Ensure the kit is in a waterproof container or bag — a first aid kit that has been rained on is often unusable