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Wound Management nishitarumizu          2000.9.19

I. General Principles

    The goal of wound management is primarily restoration of function, which requires minimizing
   risk of infection and repair of injured tissue with a minimum of cosmetic deformity. Be sure to
   maintain universal precautions.  

II. Significant History

  A. Mechanism of injury.
     1.Blunt trauma. Split or crush type of injuries will swell more and tend to have more
      devitalized tissue and a higher risk of infection.
     2.Sharp trauma. Clean edges, low cellular injury, and risk of infection.
     3.Puncture wounds.
     4.Bite injury.
  B.Contaminants.
     Wound contact with manure, rust, dirt, etc., will increase risk of infection.
     Wounds sustained in barnyards or stables are considered contaminated.
     Clostridium tetani is indigenous in manure.
  C.Time of injury.
     After 3 hours, the bacterial count in a wound increases dramatically.Wounds may be closed
      primarily up to 12-18 hours out; clean well and use clinical judgment when choosing which
      wounds to close.
     Wounds up to 24 hours old on the face may be closed after good cleaning. The blood supply
     in this area is much better and the risk of infection therefore much less.
     The risk of infection may be reduced in wounds by use of tape closures (such as Steri-Strip
     tape).
  D.Tetanus status(http://homepages.go.com/homepages/a/n/e/anealkhan/tetanus_prophylaxis.htm)
  E.Other medical illnesses.
     Diabetes, chemotherapy, steroids, peripheral vascular disease, and malnutrition may delay
     wound healing and increase the risk of infection.  

III.Physical Exam

    A.Vascular injury.
       Direct pressure is the first choice for controlling bleeding.
       If a fracture is involved, immobilization will help control bleeding. Do not clamp
       vascular structures until it is determined if it is a significant vessel needing repair.
       If the anatomy is suspicious for injury to major vascular structures, obtain angiogram
       and consider surgical consult. Capillary refill should be checked distally. Bleeding on
       the scalp is best controlled by suturing of the wound. For extremities, inflating a
       blood pressure cuff above systolic pressure assists in wound inspection and repair.
       However, be careful not to cause ischemic injury to the extremity.

    B.Neurologic injury.
       Check distal muscle strength and sensation. Always check sensation
       before administering anesthesia. For hand and finger lacerations
       check 2-point discrimination, which should be less than 1 cm at the fingertips.
       A crush injury may also decrease 2-point discrimination. This may take several months
       to recover. A lacerated nerve may be repaired immediately or have repair delayed. Loss
       of sensation may be the first sign of a developing compartment syndrome.

    C.Tendons.
       Can be evaluated by inspection, but individual muscles must also be tested for
       full range of motion and full strength.

    D.Bones.
       Check for open fracture or associated fractures. X-ray if any question.
       An open fracture is an indication for surgical debridement and repair except
       in the case of a distal phalanx fracture where copious irrigation and
       oral antibiotics are acceptable treatment if the injury can be watched carefully for infection.

    E.Foreign bodies.
       Inspect and x-ray the area. Remember that wood or low-lead glass may not show on radiograph.
       Wound markers can be used during radiographing, and views obtained in two planes can help
       localize the object for recovery. Glass may penetrate at an angle and be buried deeper than
       it appears to be.
       Ultrasonography is very sensitive at picking up foreign bodies if radiograph is questionable
       or there is strong clinical suspicion.

IV.Repair

    A.Wound healing.
      1.Ephithelialization occurs in 24-48 hours under optimal conditions.
      2.Collagen formation. Peaks at day 7. Wound has 15% to 20% of full strength at 3 weeks,
        60% full strength at 4 months. The wound is then completely sealed.
      3.Scar formation. Requires 6 to 12 months for a mature scar.
        The smallest scar will be formed when the wound is not under
        tension. Scars should not be revised until 12 months
        have passed. Contractures can develop when a scar intersects
        perpendicularly to a joint crease.
    B.Wound preparation.
      Hand washing, face masks are recommended.
    C.ANESTHESIA
      1.In general, pain control should be provided before extensive
       wound preparation.
      2.Local. Use 27- or 30-gauge needle and infiltrate slowly and
       through the open wound edge avoiding the intact skin.
       This decreases the pain of infiltration. The addition of
       bicarbonate to lidocaine before infiltration has been shown to
       significantly decrease the pain of injection (9 ml of lidocaine
       and 1 ml of bicarbonate) and warming lidocaine to body temperature
       may help as well.
        a.Lidocaine (0.5% to 2%) most frequently used with onset 2 to 5
         minutes, duration 60 minutes. Can use 3 to 5 mg/kg with not
         more than 300 mg total (in adults). Avoid using lidocaine with
         epinephrine on distal extremities such as the ears, fingers,
         toes, and penis.
        b.Mepivacaine (Carbocaine) has onset 3 to 5 minutes, duration of
         90 to 120 minutes.
        c.Bupivacaine (Marcaine) has onset 5 to 10 minutes, duration of
         hours; longest lasting of the local anesthetics. Intravenous
         administration may cause serious arrhythmias.
        d.For "caine" allergies, use diphenhydramine diluted to 1%.
         Mix 5% diphenhydramine 1:4 ml with normal saline to make a
         1% solution. Onset of anesthesia takes longer and does not
         last so long as with lidocaine. Stronger solutions may cause
         tissue necrosis.
      3. Regional anesthesia. Especially good for fingers, hands, feet,
        toes, mouth, and face. See Chapter 17 for common blocks.  

      HEMOSTASIS
         Control of bleeding is necessary for both hemodynamic
        stability and for proper evaluation of a wound.
         Direct pressure, epinephrine, bipolar electrocautery,
        tourniquet.

      FOREIGN -BODY REMOVAL
         Avoid the temptation to initially explore wounds with a finger
        in search of foreign body. Plain radiography , US, CT

      HAIR REMOVAL
         Shaving the area with a razor damage the hair follicle,
        allowing bacterial invasion, and is associated with a ten fold
        increase in infection rate when compared with clipping. Hair
        should be as completely as possible with clipping 1to 2 mm above
        the skin with scissors.
         Never shave eyebrows because they are needed for alignment of
        the wound and may not grow back.

      IRRIGATION
         Irrigation pressures of 5 to 8 psi are recommended, which is
        achieved using a 19-guage needle with either 35-ml or 65-ml
        syringe.
         Fluid (saline) volume : 60ml /cm of wound length. 200ml-
        1000ml.
         There is no added benefit to the addition of an antiseptic (
        such as povidone-iodine or hydrogen peroxide) . All detergents
        cause tissue and fibroblast toxicity.  

      DEBRIDEMENT
         Not only removes foreign matters, bacteria, and devitalized
        tissue,but also creates a sharp wound edge that is easier to
        repair.
         Using aseptic technique, devitalized tissue should be removed;
        avoid taking healthy tissue. High-pressure irrigation is the
        most effective means of cleansing a wound. Scrubbing does not
        cleanse the wound as well and using any disinfectant in the
        wound damages healthy cells needed for healing.

      SKIN DISINFECTION
         Can be performed with povidone-iodine solution or
        chlorhexidine.    
         Avoid getting these solutions in the wound because they impede
        wound healing.

    D.Wound closure.
      1.Avoid primary closure of infected and inflamed wounds, dirty
        wounds, human and animal bites, neglected and severe crush  
        wounds,and puncture wounds.
      2.Tape closure (with Steri-Strips or others). Strips carry a lower
        risk of infection than suturing does and may be a consideration
        for higher-risk wounds.
      3.Open wound care. Saline wet to dry dressings with gauze will keep
        the tissue moist and help debride, Gentle washing of the wound 2
        to 3 times per day will remove bacterially contaminated
        secretions (showers are appropriate for this). Avoid iodine
        dressings because they damage healthy tissue and will slow
        granulation. When clean granulation tissue is apparent,
        secondary closure may be considered or can change to dry,
        sterile, packing material.
      4.Suturing.
        Sutures are of two types: (1)absorbable and (2)nonabsorbable.
        Precision-point cutting needles, and small-sized suture (5-0 or
        6-0) should be chosen for skin when a cosmetic closure is
        important as on the face. Conventional cutting needle is used
        for routine skin closure.
        4-0 or 3-0 nylon may be used on extremities.
        Noncutting needle should be used for subcutaneous tissue.
        Extensor tendons are slow healing and should have permanent
        suture of small size chosen (such as polypropylene).
        Depending on your practice situation, a surgical consultation
        should be considered.
        The majority of subcutaneous or dermal suturing may be performed
        with an intermediate-duration absorbable suture. However, some
        wounds require permanent sutures (such as stainless steel wires
        in sternotomy).
      5.Staples.
        Can be used on the scalp and abdomen with good result.
        However, avoid use on face, hand, or other areas where
        structures such as tendons and nerves may become incorporated
        into the staples.
      6.Dressings.
        Maintaining a moist environment for the first 24h-48 h
        facilitate healing. Dressing absorbs exudate, protect
        contamination, and prevention of premature removal.
        Consider antibiotic petroratum-based ointment on face and torso.
        Antibiotic ointment should be avoided on distal extremities for
        more than 24 to 48 hours because it may lead to maceration and
        delayed wound healing.
        Immobilize if motion of a joint is going to increase skin
        tension.
        Keep the wound for 24 hours, after which time most wounds do not
        require a dressing.
      7.Antibiotics.
        There is no medical indication for using prophylactic
        antibiotics in routine, noncontaminated, skin wounds.
         a.Consider antibiotic use for patients prone to endocarditis,
           patients with hip prostheses, lymphedema, contaminated foot
           wound in diabetics, or others with peripheral vascular
           disease.
         b.See Chapter 1 for antibiotic choices for bite wounds.  

V.Follow-Up Care

    A.Risk of infection highest 24 to 48 hours, and so all wounds should
      be rechecked at 48h.
    B.Washing and Grooming Within 8 to 24h after closure, wounds in highly
      vascular areas can be washed. Other areas can be washed after 12-
      24h without increased an adverse outcome. However, immersion or
      soaking should be avoided.
    C.General guidelines for suture removal. Face, 3 to 5 days with tape
      reinforcement after suture removal. Scalp, 7 to 10 days; trunk,
      7 to 10 days; arms, 7 to 10 days; legs, 10 to 14 days; joints,
      dorsal surface, 14 days. Increase length for diabetics or
      steroid-dependent patients who may require several weeks to heal.