Field wound management has two phases: immediate care (stop bleeding, clean the wound, close or pack it) and ongoing care (monitor for infection, protect from contamination, reassess closure). Both phases matter — a clean closure that later becomes infected can be more dangerous than a wound left open and properly dressed. This article is a companion to wilderness first aid: 15 field-treatable emergencies.
Wound Assessment: What You’re Working With
Before treating, assess the wound across four dimensions:
- Depth: Superficial (skin only), partial thickness (into dermis), or full thickness (through all skin layers, potentially involving underlying structures). Full-thickness wounds over joints, the abdomen, or neck require evacuation.
- Contamination: Clean (surgical cut), contaminated (field laceration), or dirty (animal bite, soil-contaminated wound). Contamination level determines closure decision.
- Age: Wounds over 6–8 hours old should not be closed primarily — bacterial load has increased beyond what irrigation can adequately reduce. Close after 4–5 days (delayed primary closure) once infection risk decreases.
- Location: High blood supply areas (face, scalp) are more infection-resistant. Extremity wounds, especially feet and hands, are higher infection risk.
Irrigation: The Most Important Step
Mechanical irrigation removes bacteria, debris, and foreign material — it is more effective at reducing infection risk than antibiotics in most wound scenarios. The pressure required to be effective: 8–10 psi. This is produced by a 60mL syringe with a small-bore tip (18-gauge catheter tip or commercial irrigation tip).
Volume guidelines: 100–200mL per inch of wound length for clean wounds; 200–300mL per inch for contaminated wounds. An irrigation kit produces approximately 3–5 psi per squeeze of a squeeze bottle — insufficient pressure without a syringe-tip system. A small plastic bag with a pinhole produces approximately 8 psi when squeezed — an improvised substitute that works.
Irrigation fluid: sterile saline (ideal) or potable water (clean enough to drink = clean enough to irrigate). Do not use hydrogen peroxide, iodine, or bleach solutions directly in wounds — these damage tissue and impair healing. Dilute iodine (povidone-iodine at 1:10 dilution = pale-tea color) is acceptable for wound irrigation in contaminated wounds, but full-strength iodine is tissue-toxic.
Wound Closure: When and How
Close: Clean lacerations under 6 hours old, clean edges, low contamination, not over a joint or high-tension area.
Do not close: Wounds over 6–8 hours old, animal bites, highly contaminated wounds, deep puncture wounds, wounds over joints with potential joint penetration, and wounds where bleeding has not been fully controlled.
Closure methods:
- Steri-Strips (wound closure strips): Best for lacerations under 1.5 inches with clean edges in low-tension locations. Dry the skin thoroughly (no closure strip adheres to wet skin). Apply benzoin adhesive to surrounding skin first (not in wound) to improve strip adherence. Strips placed perpendicular to the wound, pulling edges together. Change at 3–5 days. Disadvantage: fall off in wet conditions.
- Cyanoacrylate (super glue / Dermabond): Apply a thin bead along the wound edges while approximating them. Hold in position for 60 seconds. Creates a waterproof seal. Works on clean wounds in non-high-tension areas. Disadvantage: cannot be easily removed if infection develops; bonds to anything it contacts (including fingers — use sparingly).
- Field sutures: Reserve for wounds requiring significant tension to close that strips cannot maintain. Interrupted sutures with 3-0 nylon provide the most reliable closure for extremity skin. Skill-dependent — poor technique produces suboptimal results and increased infection risk.
Dressing and Wound Protection
Wound dressing serves two purposes: contamination barrier and absorption. Field dressing components:
- Contact layer: Non-adherent dressing (Telfa pad) directly over the wound. Prevents the gauze layer from sticking and disrupting the wound on removal.
- Absorptive layer: Gauze pad (4×4 or 2×2) over the Telfa. Absorbs exudate.
- Securing layer: Medical tape or self-adherent wrap (Coban). Avoid wrapping so tightly that it compromises circulation.
Change dressings when they are saturated, soiled, or every 24–48 hours. Each dressing change is an opportunity to reassess for infection.
Recognizing Infection: Signs and Timeline
Normal wound healing produces warmth, redness, and swelling at the wound margins for the first 24–48 hours. Infection produces these same signs but they worsen after 48 hours rather than improving. Specific infection signs:
- Cellulitis: Red streak or spreading redness beyond the immediate wound margin. The red border of cellulitis should be marked with a marker and checked every 4–6 hours — advancing cellulitis (spreading redness beyond the marked border) indicates treatment is failing.
- Purulent discharge: Thick yellow, green, or brown exudate from the wound. Distinguished from clear or pale-yellow serous drainage (normal). Purulent discharge = wound infection.
- Systemic signs: Fever above 101°F (38.3°C), chills, tachycardia, or confusion in the context of a wound indicates infection has spread beyond the local tissue. Evacuation required.
Antibiotic Indications in the Field
Prophylactic antibiotics are not indicated for clean lacerations in healthy patients — they do not prevent infection but do select for resistant organisms. Antibiotics are indicated for:
- Animal or human bites (high polymicrobial contamination)
- Confirmed wound infection with cellulitis or purulent drainage
- Wounds to hands, feet, or over joints in immunocompromised patients
- Heavily contaminated wounds that could not be adequately cleaned
First-line field antibiotic for skin/soft tissue infections: amoxicillin-clavulanate (Augmentin) 875mg twice daily for adults, or doxycycline 100mg twice daily as an alternative. These require prescription — obtain and carry with medical provider guidance before a wilderness expedition.
Where to Go Next
The complete 15-emergency wilderness first aid reference is in wilderness first aid: 15 field-treatable emergencies. Fracture management and splinting technique are in improvised splints and fracture management in the field. Hypothermia, heat stroke, and shock treatment protocols are in recognizing and treating hypothermia, hyperthermia, and shock.
