DEEP WOUND CARE
by Buck Tilton

Three basic principles describe the general goals of deep, open wound care when in the field: 1.) stop blood loss, 2.) prevent infection, and 3.) promote healing. Here we'll concentrate on 2.) and 3.), and we'll consider "the field," as a place long hours from or forever beyond the reach of a doctor. We'll think of a deep wound as a wound that will require closure.

Wound Cleansing
You're rarely, if ever, safe from exposure to infectious agents (such as hepatitis B and HIV) when you deal with open wounds. You may be using fluids under pressure and sharp objects, both of which increase your personal risk. Take the time to put protective gloves on and, perhaps, a pair of medical or safety glasses before you start cleaning a wound.

Water safe to drink is safe for cleaning wounds, and most wounds can be adequately cleaned with water only. If clean water is scarce, you will get satisfactory results from povidone iodine solution. Unlike povidone iodine scrub, the solution contains no detergent and is effective against bacteria, viruses, and fungi. Another well-tested and proven cleaning solution is the non-detergent Polaxamer 188 (sold as Shur Clens®). Its major shortcoming is its lack of anti-bacterial activity.

The single most effective method of reducing bacterial count on wound surfaces, and removing debris and contaminants, is wound irrigation. For optimal results, use an 18 gauge needle or plastic catheter and a 35cc syringe. Hold the needle 1-2 inches from the wound; too far away reduces the force of the stream. Your ability to improvise is only limited by your imagination – you may melt a pinhole in the top of your Nalgene bottle or punch a pinhole in a plastic bag to create an irrigation system. The amount of fluid forced through the wound can vary. Keep irrigating until the wound looks as clean as possible.

Although wound soaking has been long practiced as a cleaning method, there is no evidence to support its use. It is recommended only when ground-in dirt and debris litter the wound's periphery.

Shaving off the hair around an open wound is another time-honored practice that should be avoided. Hair around a wound can be easily cleaned with normal washing techniques, and shaving often produces micro-tears in the skin, another source of infection.

Wound Closure
When considering how a wound should be closed, consider first the mechanism of injury. There are three general mechanisms for deep lacerations: 1.) Sharp objects, such as knives, produce a simple division of tissue resulting in a shearing injury that is relatively simple to deal with by pulling the wound's edges together. 2.) Blunter objects, striking the skin at an angle of less than 90 degrees, often produce a partial avulsion, a tension injury, requiring more careful closure of the irregular division of tissue. 3.) Blunt objects, striking the skin at a right angle, produce a crushing injury with very irregular borders, lots of devitalized tissue, and many problems for the person trying to close the wound.

Another wound deserving of a few words is a deep puncture, which includes animal bites. With the high potential for infection these wounds carry, aggressive irrigation, and possible debridement are indicated.

There are three categories of wound closure:

1.) Primary closure is performed on clean wounds with fairly regular borders. These wounds are most often shearing injuries. Closure can wait for 24 hours on the face, and up to 12 hours on other body parts. In the field these wounds can be closed with closure strips, staples, or sutures. Strips work best if you first lay down a line of benzoin tincture along both sides of the wound, being careful to keep the benzoin out of the wound. The stickiness of benzoin makes the strips stay in place much better. Start a strip on both sides of the wound, using them as handles to pull the wound closed. Skin staplers needs to be cocked, which pushes the sharp staple ends partially out of the stapler. Placing one staple end in the skin on one side of the wound, pull the wound closed, and place the other staple end in the skin on the other side of the wound. And staple! After strips or staples, run a bead of antibiotic ointment along the closed wound and dress with sterile gauze. Better yet, a micro-thin dressing, such as Tegaderm®, may be used. Micro-thin dressings are see-through, allowing you to monitor the wound for infection, long-lasting, and waterproof. Micro-thin dressings should be placed over a closed wound without the application of ointment. In general, staples and sutures produce identical scars, but staples should not be used on the face, hands, or feet. (Note: Deep wounds to the face, scalp, hands, and feet should be evaluated as soon as possible by a physician, if one is available, to ensure minimum scarring and, because of their unique anatomical structure, maximum healing.) For suturing instructions (not generally recommended for the untrained), refer to Dr. William Forgey's Wilderness Medicine (Globe Pequot Press, Guilford, CT).

2.) Secondary closure is required for deep punctures, deep animal bites, ulcerated wounds, and abscess cavities. They are usually best managed by careful cleaning, but no strips, sutures, or staples. Secondary closure is closure by allowing the wound to heal on its on.

3.) Tertiary closure is delayed closure. These wounds are cleaned and observed for 4-5 days before mechanical closure. This type of wound would be very contaminated, probably with dirt or saliva, but it would not be associated with significant tissue loss.

Wound Healing
The tensile strength of a deep wound actually decreases during the first seven to ten days after closure. There is a high risk of wound separation during this period, and the wound tends to heal better if kept still. Arm and leg wounds can be splinted to maintain wound stability. The splint should not be places over the wound. Final tensile strength will not be reached for several months after closure.

All wounds undergo some contraction during healing. This produces a depressed and uglier scar unless the edges of the wound are slightly everted (pushed upward) when they are pulled together. This is not always as easy as it sounds.

Closure Issues
1.) Foreign objects lodged in soft tissue may be a source of complications. They fall into two classifications: inert and non-inert. Inert materials include metals and other compounds that do not cause a tissue reaction. Inert materials do not have to be removed from a deep wound. In fact, sometimes they are just left in permanently where they encyst and lay harmlessly for the rest of the patient's life. Wood, thorns and other non-inert materials must be removed from a deep wound. They can cause a variety of bacterial and fungal infections. Glass fragments are generally inert but sometimes cause a tissue reaction.

2.) Debridement is the removal of visible contaminants and devitalized tissue. These things will prevent healing. Devitalized tissue can be recognized by its shredded, ischemic, blue or black appearance. With tissue scissors or scalpel (or a very sharp knife) this tissue should be carefully cut away. The overriding principle for debridement is, as Dr. Alexander Trott, author of Wounds and Lacerations: Emergency Care and Closure, writes: ". . . spare as much tissue as possible immediately after the injury." If in doubt about tissue, leave it alone.

3.) If you're carrying antibiotics appropriate for deep wounds, should you use them? Generally, start antibiotics with a.) heavily contaminated wounds, b.) crushing injuries, especially if they're noticeably contaminated, c.) wounds that involve cartilage, joint spaces, tendons or bones, d.) mammalian bites, including human bites, and e.) wounds that are 12-24 hours old when you see them. First generation cephalosporins (e.g., Keflex) are a reasonable choice for prophylaxis. Patients allergic to penicillin may react to cephalosporins. Erythromycin can be used for such patients.