Parameters	Factors to Consider
Mechanism of injury	Sharp vs. blunt trauma, bite
Dirty vs. clean	Outdoors vs. kitchen sink
Time since injury	Suture up to 12 h; 24 h on face
Foreign body	Explore and obtain radiograph for metal or glass
Functional examination	Neurovascular, muscular, tendons
Need for prophylactic antibiotics	If needed, give ASAP and cover Staphylococcus aureus; irrigate well

In general, antibiotics are not needed for either wound or subacute bacterial endocarditis (SBE) prophylaxis for cutaneous procedures ¹ (see Chapter 1). Consideration should be given to coverage for Staphylococcus aureus and MRSA infection in several situations.

The following are major goals for prescribing antibiotics before or after skin surgery:

1. Prevention of a new wound infection

2. Prevention of the spread of an existing local infection

3. Treatment of an existing infection

4. Prevention of bacterial endocarditis.

The clinical decision-making process of whether or not to use antibiotics before or after skin surgery is complex. The physician must consider host factors, the anatomic location of the surgery, the sources that might contaminate the wound, and method of wound injury. The multiple factors to be considered when making a decision about antibiotic prophylaxis for skin procedures are:

Coexisting Conditions

• Diabetes mellitus

• Peripheral vascular disease

• Frail elderly patients

• Immunocompromised

• Previous radiation to the site

• Malnutrition (e.g., alcoholism, chemotherapy)

• History of previous infection or slow healing

• Chronic steroid use

• Morbid obesity.

Locations

• Axilla, mouth and anogenital areas have higher levels of bacterial colonization

• End arterial locations (fingers, toes) with diseases of vascular compromise

• Over joint spaces where there is a possibility of entering joint (e.g., metacarpal-phalangeal joints).

Contamination

• Dirty wounds, especially barnyards, meatpacking plants, etc.

• Less than optimal sterile technique (should be rare)

• Deep puncture wounds

• Bites (especially human and cat bites)

• Presence of a retained foreign body.

Method of Wound Injury

• Crush injury (10-fold increase in infection) with devitalized skin

• Penetrating injury.

The recommendations of the American Heart Association (AHA) for the prevention of bacterial endocarditis were last published in 2007 and are discussed in Chapter 1.¹ Endocarditis prophylaxis is not needed for incision or biopsy of surgically scrubbed noninfected skin no matter what endocarditis risk factors are present. The 2007 guidelines state that antibiotic prophylaxis is recommended for procedures on infected skin and skin structures for patients with underlying cardiac conditions associated with the highest risk of adverse outcome from infective endocarditis (see Chapter 1, Box 1-2 and Table 1-3).¹

Cummings et al. performed a meta-analysis of randomized studies on the use of antibiotics to prevent infection of simple wounds.² They concluded that there is no evidence in published trials that prophylactic antibiotics offer protection against infection of nonbite wounds in patients treated in emergency departments. However, prophylactic antibiotics did reduce the incidence of infection in patients with dog-bite wounds in another meta-analysis.³ The authors concluded that it may be reasonable to limit prophylactic antibiotics to patients with dog-bite wounds that are at highest risk for infection.³

Controversy exists over which bite injuries should be treated with prophylactic antibiotics. Cat- and dog-bite injuries carry the risk of infection with Pasteurella multocida, and human-bite injuries carry the risk of infection with Eikenella corrodens and S. aureus. Based on the microbiology of these wounds, amoxicillin/clavulanate provides good prophylactic coverage for the bacteria affecting most bite injuries. Alternatives include second-generation cephalosporins or clindamycin with a fluoroquinolone.

Antibiotics have a role in the treatment of many established skin infections. However, most skin abscesses are better treated with incision and drainage rather than with antibiotics. For skin procedures of infected skin, no specific evidence exists as to whether to give an antibiotic and the appropriate timing for its administration. Recommendations for timing before the procedure vary from 1 hour (which is typical timing for bacterial endocarditis prophylaxis) to within 30 minutes of the procedure. Whereas a single second dose 6 hours later was the standard in the past, it is no longer currently recommended for bacterial endocarditis prophylaxis but may be advocated for further treatment of the infection.

The best method for prevention of wound infections is to clean and irrigate traumatic wounds well, rather than relying on prophylactic antibiotics. The physician needs to weigh the benefits and the risks of antibiotic use based on the individual patient and the circumstances of the wound repair or skin surgery.

Local and Regional Anesthesia

In traumatic wounds, neurovascular integrity should be assessed prior to administration of anesthesia. The wound should then be fully anesthetized to allow for painless examination of the tissue damage, thorough irrigation, and adequate closure. Many wounds can be adequately anesthetized with 1% or 2% lidocaine. Consider using lidocaine with epinephrine to provide increased hemostasis if there are no contraindications to epinephrine use in the patient, the location, or the wound itself (see Chapter 3, Anesthesia). Topical anesthetics are effective for wounds that do not involve mucosal surfaces. A combination of lidocaine, epinephrine, and tetracaine (LET) applied with a saturated cotton ball or as a gel formulation directly into the wound provides adequate anesthesia for many wounds.^4,⁵

Regional anesthesia may be desirable in cases where the volume of locally infiltrated anesthesia might exceed the safe maximum dosage (see Chapter 3, Table 3-3) or in cosmetically important areas where a local infiltration might distort the anatomy to impair a meticulous closure. If a regional anesthetic technique is employed, lidocaine without epinephrine is the optimal choice, because epinephrine’s role as a vasoconstrictor is not needed at a site remote to the traumatic wound.

Follow these instructions to minimize the pain of injecting local anesthetic:

• Use a small-gauge needle (27 or 30 gauge).

• Inject slowly.

• Inject directly into the dermis through the open wound (not through intact skin).

• Warm anesthetic to body temperature (optional).

• Buffer the anesthetic with sodium bicarbonate (1 mL bicarbonate for .9 mL lidocaine) (optional).

Wound Preparation

After the initial assessment and administration of local or regional anesthetic, and antibiotics if indicated, wounds should be inspected thoroughly for foreign bodies, deep tissue layer damage, and injury to nerve, vessel, or tendon. Underlying bone or joint injury should be considered in wounds sustained as a result of traumatic force. A radiograph should be obtained to look for retained glass or metal in wounds sustained from broken glass or metal and to assess for joint integrity or fractures in traumatic injuries. Complex wounds or those in cosmetically important areas should be closed by a practitioner with the appropriate expertise.

Determine If the Wound Needs Intervention to Close

One study assessed the difference in clinical outcome between lacerations of the hand closed with sutures and those treated conservatively.⁶ Consecutive patients with uncomplicated lacerations of the hand (full thickness < 2 cm; without tendon, joint, fracture, or nerve complications) who would normally require sutures were randomized to suturing or conservative treatment. The mean time to resume normal activities was the same in both groups (3.4 days). Patients treated conservatively had less pain and treatment time was 14 (10 to 18) minutes shorter. The groups did not differ significantly in the assessment of cosmetic appearance on the visual analogue scale. Conservative treatment was faster and less painful.⁶

Cleansing

After the wound is anesthetized, cleansing of the wound should be performed by irrigation with normal saline at 8 to 12 psi of pressure. This can be accomplished by attaching an 18-gauge angiocatheter or a commercially available splash shield to a 20- or 30-mL syringe. At least 200 mL of irrigation is recommended. Irrijet and Zerowet were superior to an angiocatheter in preventing splatter during wound model irrigation.³ Zerowet was particularly effective in preventing splatter onto the irrigator’s face (Figure 7-1).³

A multicenter comparison of tap water versus sterile saline for wound irrigation published in 2007 showed equivalent rates of wound infection in immunocompetent patients.⁷ The tap water group irrigated their own wounds under the water tap for a minimum of 2 minutes after they had the wound anesthetized. Higher risk wounds were excluded from the study, indicating that tap water is a reasonable cleansing alternative for low-risk lacerations. In one randomized clinical trial, warmed saline was more comfortable and soothing than room-temperature saline as a wound irrigant among patients with linear lacerations.⁸

Chemical compounds such as hexachlorophene (pHisoHex), chlorhexidine gluconate (Hibiclens), or povidone-iodine (Betadine) should not be used inside wounds but may be applied to external, intact skin if desired. Greasy contaminants can be removed with any petroleum-based product, such as petrolatum or bacitracin ointment. To prevent a road rash tattoo, wrap petroleum gauze around the fingers and wipe off the asphalt and other foreign material embedded in the skin after anesthesia. Topical and regional anesthetic techniques are particularly effective in this situation.

Debridement

After the cleansing process, wounds should be examined for devitalized tissue that needs removal or debridement. This debridement may convert a jagged, contaminated wound into a clean surgical one and can be accomplished with a scalpel or sharp tissue scissors. As much tissue as possible should be preserved in case future scar revision is necessary. After debridement, wound edges should be held together to see if they are under any tension. Wounds under significant tension are best repaired by a two-layer closure. In dirty wounds, however, this may increase the incidence of infection.

Undermining

Undermining can significantly reduce skin tension when there is a gap to be closed. Undermining may increase the risk of infection and thus should be avoided in dirty wounds. Care should be taken to minimize the use of this technique in areas with poor blood supply, because the process of undermining reduces it further. Extreme care is also needed when undermining around vital structures. Approximately one-third to one-half of the undermined tissue is freed up to be brought into the defect. When needed and if possible, undermine bilaterally as far back as the wound is wide.

Closure Technique

Ideally, four principles should be incorporated in the process of closing any wound:

1. Control all bleeding before closure. This can be accomplished by applying direct pressure for at least 5 minutes, applying an ice pack, adding epinephrine to the local anesthetic when appropriate, with electrocoagulation, or by tying off bleeders with absorbable sutures.

2. Eliminate “dead space.” Eliminate areas where tissue fluid and blood can accumulate.

3. Accurately approximate tissue layers to each other. Scars are most visible when shadows are created by depressed or elevated tissue. Also be sure that anatomic areas match on each side in critical areas such as the vermilion border of the lip or the eyebrows.

4. Approximate the wound with minimal skin tension. If the amount of tension will be significant, undermining and/or deep, inverted, buried sutures are used to decrease the tension on the skin margin. Ideally, when the repair is completed the wound will be tented up slightly.

Choice of Sutures

Most lacerations will be closed with nylon. If a two-layer closure is needed, an absorbable suture such as polyglactin 910 (Vicryl) or a synthetic absorbable monofilament suture is a good choice for the deep layer. Silk sutures may be considered for closure in the mouth or other areas where the nylon ends will be bothersome. Alternately, rapidly absorbing Vicryl Rapide may be used in oral lacerations without the need for suture removal. In one study, otherwise healthy children with facial lacerations were randomized to repair using fast-absorbing catgut or nylon suture.⁹ There were no significant differences in the rates of infection, wound dehiscence, keloid formation, and parental satisfaction between the absorbable catgut and the nylon suture.⁹ Fast-absorbing catgut suture is not as easy to work with as nylon but does have the advantage of not requiring suture removal in children who may be very fearful of the suture removal process.

TABLE 7-2 Suture Size and Time of Removal

Sutured Repairs

Lacerations are approximated with sutures using a variety of techniques (see Chapter 6, Suturing Techniques), as discussed in the following subsections.

Simple Interrupted Suture

On completion of a simple interrupted suture (Figure 7-2), the skin margins should be slightly everted. The needle should enter the skin surface at a 90-degree angle. The stitch should be as wide as it is deep. The suture on both sides of the wound should be equal distance from the wound margin and of equal depth. The final shape should appear like that of a pear (see Chapter 6, Figure 6-5). As a general rule, these sutures need to be no closer than 2 mm in a fine plastic closure and can be substantially farther apart in other types of closures. The distance between sutures should equal half the total distance of the sutures across the incision. The finer the suture, the closer the stitch needs to be. Avoid tying the knots too tightly. The knots should be lined up on the same side of the wound, usually the one with the best blood supply or least interference with comfort (e.g., away from eyelid).

FIGURE 7-2 Simple interrupted suture of a small nose laceration.

(Copyright Richard P. Usatine, MD.)

Simple Running Stitch

The advantages of the simple running stitch (Figure 7-3) in sterile wounds under little or no tension are that it is quick, it distributes tension evenly, and it provides excellent cosmetic results. If there is significant gaping of the wound, interrupted suture methods should be used. Because the risk of contamination is increased with traumatic lacerations, the simple running stitch is less desirable in these wounds. In case of infection, the entire wound closure would need to be removed. The relative disadvantage of removing the entire stitch at one time also poses a problem in wounds under some increased tension. With interrupted techniques, some sutures may be removed early for better cosmesis, whereas a few remaining ones can be left for prevention of dehiscence and removed at a later date. The simple running stitch is ideal in the scalp and is often used in elliptical excision repairs.

FIGURE 7-3 Running stitch. Always keep the depth of the suture placement the same on each side.

(Copyright Richard P. Usatine, MD.)

Deep Suture with Inverted Knot or Buried Stitch

Deeper wounds or wounds under tension are best closed by providing structural support and not relying solely on nonabsorbable superficial sutures. Well-placed deep absorbable sutures (Figure 7-4 and Chapter 6, Figure 6-9) can do much to aid in closing a wound, remove tension from the superficial skin sutures, and decrease scarring by providing increased wound support long after the epidermal sutures have been removed. Deep sutures also close dead space, which decreases the risk of hematomas and dehiscence.

FIGURE 7-4 Deep stitch with absorbable suture material. The suture needle should enter deep in the skin below the dermis where the undermining was accomplished and exit in the upper dermis.

(Copyright Richard P. Usatine, MD.)

The inverted knot technique places the knot as far below the skin margins as possible to avoid suture spitting (migration of deep sutures to the skin surface). It also keeps the ends of the cut suture from protruding through the wound margin. To start the stitch, begin at the bottom of the wound (in the undermined area if undermining was used) and come up usually just below the epidermal-dermal junction (remember, “Bottoms up!”). Go straight across the incision, enter at the same level at the opposite side, then go down to the base at the same depth once again and tie. Care should be taken to achieve symmetry of depth and width on both sides of the laceration. For a more detailed discussion of the deep vertical mattress suture, see Chapter 6. The epidermis is then fully closed with a closure of choice (nonabsorbable suture, wound closure strips, or tissue adhesive).

Vertical Mattress Suture

The vertical mattress suture (Figure 7-5 and Chapter 6, Figure 6-12) promotes eversion of the wound edges of the skin. It is also useful when the natural tendency of loose skin is to create inversion of the wound margins, which should be avoided. A good example is the loose, flabby skin under the triceps muscle and thin skin in older people. The stitch is also appropriate when the skin is very thin and interrupted sutures have a tendency to pull through.

FIGURE 7-5 Vertical mattress suture.

(Copyright Richard P. Usatine, MD.)

Horizontal Mattress Suture

The horizontal mattress suture (see Chapter 6, Figure 6-13) is helpful in wounds under a moderate amount of tension and also promotes wound edge eversion. It is especially useful on the palms or soles and in patients who are poor candidates for deep sutures because of susceptibility to wound infections. It is not recommended in wounds that are located in cosmetically important areas.

Subcuticular Running Suture (Figure 7-6 and Chapter 6, Figure 6-17)

The subcuticular running suture (Figure 7-6 and Chapter 6, Figure 6-17) is used to close linear wounds that are under minimal tension; it yields an excellent cosmetic result. It is advantageous in patients who tend to form hypertrophic scars or keloids, because it minimizes the number of times the skin’s surface must be perforated with the suture needle. Meticulous alignment of each stitch is critical to prevent gaps in the linear wound. The ends of the suture do not need to be tied; taping under slight tension preserves approximation. If desired, the two ends can be tied over the wound, or a knot can be placed at each end to prevent slippage. Usually a polypropylene-coated nylon works best. Steri-Strips, strips, or tissue glue can be used to supplement this type of stitch. Special care must be taken to avoid pressure on the wound, since this stitch separates easily.

FIGURE 7-6 Subcuticular running suture.

(Courtesy of Joe Deng, MD.)

Three-Point or Half-Buried Mattress Suture (Chapter 6, Figure 6-15)

The three-point or half-buried mattress suture (see Chapter 6, Figure 6-15) is designed to permit closure of the acute corner tip of a laceration without impairing blood flow to the tip. It is an intradermal stitch in which the needle is inserted initially into the intact skin on the nonflap portion of the wound and passed through the skin at the mid-dermis level; at the same level, the suture is then passed transversely through the tip of the flap, returned on the opposite side of the wound, and brought through the skin, paralleling the point of entrance. The suture is tied by drawing the tip snugly into place in good approximation. Care should be taken not to have the knot tied over the point of the flap. This same approach can be used in closing a stellate laceration, drawing the tips together in a purse-string fashion. The resulting knot should be placed over the segment of the stellate laceration with the best blood supply. Repair of a “T” laceration also uses this technique.

Surgical Adhesive Strips (Steri-Strips)

Surgical adhesive strips may be used alone for small, superficial wounds (especially in young children).^10,¹¹ When these strips suffice to close a wound, they are more easily placed without physical or psychological trauma to the child. Wounds closed with adhesive strips are more resistant to infection than are sutured wounds. However, surgical adhesive strips are not appropriate for deep lacerations because they do not provide adequate deep-tissue approximation or skin-edge eversion when used alone. Surgical adhesive strips with or without gum mastic did not provide any additional strength to wounds closed by subcuticular continuous suture.¹² Surgical adhesive strips are especially helpful after suture removal to prevent dehiscence and may be left on until they fall off. Patients may shower with them on after the initial 24 hours.

Surgical adhesive strips adhere better to the skin when a sticky substance is applied to the skin first. Tincture of benzoin and gum mastic (Mastisol) are both helpful. Studies have shown that gum mastic offers superior adhesive qualities compared with benzoin and has a lower incidence of postoperative contact dermatitis and subsequent skin discoloration.^13,¹⁴

Tissue Adhesives

Tissue adhesives may be used to close certain wounds that are not under any tension and are not at risk for infection. These can be purchased as octylcyanoacrylate (Dermabond) and butylcyanoacrylate (SkinStitch). A Cochrane systematic review provides evidence that tissue adhesives are an option to sutures, staples, and adhesive strips for the management of simple traumatic lacerations that are not under tension nor prone to wound infection.¹⁵ Overall, no significant differences were found in cosmetic scores at the reported assessment periods between tissue adhesives and these other methods. At 1 to 3 months, a subgroup analysis significantly favored butylcyanoacrylate over all other skin closure methods. Tissue adhesives significantly lowered the time to complete the procedure, the levels of pain, and the incidence of erythema. However, the data revealed a significant increase in the rate of dehiscence with the use of tissue adhesives when compared with the other methods of skin closure.¹⁶

Tissue adhesives and surgical adhesive strips are both excellent “no needle” alternatives for the closure of suitable pediatric lacerations.¹⁰ These two techniques are similar in efficacy, parental acceptability, and cosmetic outcome.¹⁰ Appropriate wound preparation techniques, such as irrigation under local or topical anesthesia, are still necessary. Nail bed repair performed using tissue adhesives is significantly faster than suture repair.¹⁷ Tissue adhesives provide similar cosmetic and functional results in the management of acute nail bed lacerations.¹⁷

Tissue adhesives should be avoided on any wound that has any tension. They should not be used on any area that can be flexed (i.e., a knuckle or wrist). If it is necessary to use on a jointed area, immobilize the joint with a splint. Cover eyes with gauze when working on the forehead or near the eye. Consider using petrolatum to create a barrier between the cut and the eyes to minimize the chance of the product running into the eye. If the product enters the eye, it may be removed by applying an ophthalmic ointment, which will eventually dissolve the adhesive. This can be followed by gentle irrigation, often performed several hours later by the patient at home using water in their hands over a sink. Appropriate treatment for any resulting corneal abrasion should be followed.

Follow these guidelines, which are adapted from SkinStitch information, when using tissue adhesives (Figure 7-7):

FIGURE 7-7 Use of tissue adhesive to close a laceration not under tension. (A) Better to apply 2 or 3 thin coats rather than one thick coat. Apply drops (approx. size as above) about apart and next to the area to be covered. These small drops will prevent running and when spread will create thin coats and dry in about 30 minutes. (B) Then, twirl the applicator and use the spreader to spread the drops.

(Photographs courtesy of Richard P. Usatine, MD. Device courtesy of SkinStich Corp, Massena, NY.)

1. Tap glue down into the bottom bulb of the applicator.

2. Holding the applicator tip upright, snip the tip as close to the end as possible.

3. Never put the glue in the wound.

4. Apply a thin layer of adhesive along the edge of the area to be treated, or use the multiple dot technique.

5. Pull the adhesive across to the other side of the wound, using the applicator as a hockey stick. In effect, you are building a bridge over the minor cut or wound.

6. Hold the wound edges together for 30 to 60 seconds.

7. Apply a second and third thin coat. Remember, two or three thin layers are actually stronger than one thick coat.

8. Some patients may experience mild burning; this is normal, but warn patients so they do not move and ruin the adhesion.

9. A Steri-Strip can be used for extra strength or to keep a child from picking at the wound.

Staples

Staples are most often used to repair scalp lacerations. In one randomized trial of children (ages 1 to 16 years) with simple scalp lacerations, patients were randomly assigned to either a stapling or suturing procedure.¹⁸ Procedure time was significantly lower in the stapling group (P = 0.001). There were no significant differences in the final follow-up cosmetic score between the two groups.¹⁸ Although staples are faster to apply to the scalp, the cost of the materials is greater. Scalp stapling should not be attempted in men who are already bald or in wounds that extend to the forehead.

Delayed Primary Closure (Tertiary Intention)

Primary closure is defined by the use of sutures, strips, or adhesives to close the wound at the time of initial surgery or evaluation. Healing by secondary intention occurs when no attempt is made to close the wound and the wound heals naturally by granulation. This method is used after a simple shave biopsy, in grossly contaminated or infected wounds, or in wounds that present far too late to consider closure.

Delayed primary closure is healing by tertiary intention. This technique is used for wounds that are greater than 12 hours old (24 hours for facial lacerations) but would cosmetically benefit from closure in a few days. After anesthetizing, evaluating, and irrigating the wound, insert a small piece of petroleum gauze between the wound edges and place the patient on an antibiotic, such as cephalexin, for 5 days. On the third day, the patient should return for definitive repair. If the wound appears clean and free of infection and has not started the granulation process, the repair can proceed. The wound is reanesthetized, reirrigated, and closed primarily with nonabsorbable sutures (i.e., no deep sutures because they increase the chance of infection). The patient continues the course of prescribed antibiotics and suture removal occurs at the interval beginning at the time of suturing (Table 7-2).

Complications

The complications of laceration repair are the same as when a biopsy or surgical excision is performed (bleeding, infection, dehiscence, etc.). The main differences relate to coexisting trauma such as crush injuries that can devitalize tissue around the laceration or lead to underlying injuries to tendons, vessels, bones, or joints. For discussion of complications and their treatment and prevention see Chapter 36, Complications.

Postprocedure Patient Education

Most wounds are best protected with some sort of dressing during the first 24 to 48 hours after closure. Continued oozing might be expected or pressure might be needed. For hemostasis, a pressure dressing should be applied. This could be a folded gauze over a thin strip of sterile ointment over the suture line with tape over it, or a nonstick type of gauze dressing covered with gauze and tape. Trade names for nonstick dressings include Xeroform, Adaptic, and Telfa. It is not usually necessary to keep a wound completely dry after 24 hours, because the epidermis has formed a seal by this time. Therefore, patients may shower after 24 hours and redress the wound after gently drying it. Immersion of the laceration should be avoided because the sutures provide an avenue to introduce into the wound the bacteria present in a body of water (e.g., bath, Jacuzzi, swimming pool, lake, ocean, kitchen sink).

Moist healing (application of petrolatum after gentle washing twice daily) aids in quicker healing. Although antibiotic ointments were traditionally used for dressings postsurgically, Smack et al. determined that clean wounds heal just as well when white petrolatum is applied.¹⁹ Neomycin and bacitracin are frequent contact allergens and have not been proven to prevent infections after a laceration is repaired. Application of any of these products should be limited to the smallest possible area over the suture line. Extension over the wound edges may lead to maceration of the skin and reduce its ability to hold the sutures securely in place, thus causing them to pull through and lead to wound dehiscence.

Suggestions for the timing for skin suture removal are listed in Table 7-2.

Wounds on the face or scalp may be dressed with a thin layer of antibiotic ointment or petrolatum in lieu of a mechanical dressing. It is best to cover them at night to avoid drying. Instruct patients to return if signs of wound infection appear, including erythema, pus, lymphangitis, or fever. A routine wound check is not necessary for patients who understand the importance of monitoring the wound for signs of infection. All wounds should be covered with sunscreen for at least 6 months following the repair if they are located on areas exposed to the sun.