Key Practice Points
Wounds heal faster and with less pain when a moist environment is created by an ointment or a dressing.
Neat, well-applied dressings inspire the patient to be confident in the physician and in the prognosis for healing.
A basic wound dressing has four parts: antibiotic ointment, a nonadherent base, absorbent gauze sponges (gauze wrap if needed), and wound tape.
Antibiotic ointments can enhance the moist environment; however, studies have not conclusively shown that ointments reduce wound infection.
Uncomplicated facial and scalp wounds do not require dressings. Antibiotic ointment should be applied two to three times daily to prevent dried coagulum buildup that can interfere with suture removal.
Never wrap tape circumferentially completely around an extremity or finger. Circumferential tape can cause a tourniquet effect as the wound area undergoes natural swelling.
The first dressing change after discharging the patient should be in 24 to 48 hours to check for infection and to clean away residual blood and wound exudate.
Patients can shower between bandage changes, starting 24 to 48 hours following repair. Soaking baths, however, are discouraged.
This chapter discusses the general principles of wound dressing and some recommendations for dressing and bandaging. The recommendations depend on the type of wound, body location, and other factors. Specialized dressings for burns are discussed in Chapter 17 .
Wound Dressing Principles
The first decision to make after repairing a wound is whether to apply a dressing at all. Uncomplicated lacerations of the face and scalp are often left open. The head and face are extremely vascular, and wounds in these areas are resistant to infection. If the patient is careful and keeps the wound clean, a sutured laceration heals without event. These wounds need the regular application of a petrolatum-based antibacterial ointment to maintain a moist environment and to help prevent crusting that can interfere with suture removal. The generally accepted practice for wounds and lacerations that are not on the head or the face is to apply a wound covering, although there is little evidence that a dressing improves the eventual scar appearance of sutured lacerations. One study of uncovered surgical incisions that were sutured postoperatively could not document an increase in the rate of infection compared with dressed incisions.
When the decision is made to apply a dressing, the following principles should be observed:
The wound must remain moist. Experimental studies convincingly show that desiccation by exposure can delay epithelial layer formation significantly. A moist environment has been shown to decrease the number of days to healing and reduces wound pain.
Figure 20-1 illustrates the pathways for epidermal healing in moist and dry environments. In an uncovered wound, epithelial cells are forced to find a pathway beneath dry coagulum/exudate and dermal remnants. In practice, synthetic dressings (e.g., Adaptic, Xeroform, Telfa, and Band-Aids) are nonadherent, porous coverings that allow for the drainage of exudate but do not permit excessive desiccation. Topical antibiotic ointments can provide a moist environment for unbandaged wounds.
A dressing must be neat and uncomplicated. Sloppy or poorly applied dressings and bandages do not convince a patient that good wound care has been delivered. Many small wounds are served best by one or two simple adhesive bandages (Band-Aid). This dressing remains one of the most versatile and appropriate wound coverings yet devised.
Nonadherent, Porous Base
The base of a dressing, the portion in direct contact with the wound surface, should not be adherent. Plain, fine-mesh gauze is an example of a dressing that sticks to wounds by becoming incorporated in the coagulum. When the gauze is removed, it can disrupt healing by disturbing the delicate epithelial covering. A good wound covering also has to allow for the passage of exudate so that excessive accumulation does not occur. Adaptic, Xeroform, and Telfa are examples of nonadherent materials.
Protection from contamination is best accomplished by ensuring that, in addition to the nonadherent base, the wound is well covered with gauze sponge material and an appropriate gauze wrap. Gauze sponges help meet the protection requirement of wound dressing. Most minor wounds and lacerations produce little exudate; a simple 2 × 2 or 4 × 4 gauze sponge, or even a Band-Aid, suffices for this purpose. Complicated or contaminated wounds with a potential for infection are likely to exude freely and copiously. In addition to several layers of gauze sponges, frequent dressing changes often are necessary.
Finally, dressings should protect the healing wound and should provide partial immobilization of the injured part. Many forces can disrupt a suture line, ranging from contact with clothing to accidental minor trauma to the wound. Gauze sponges in combination with gauze wrapping suffice for the purpose of wound protection. Occasionally, rigid splinting, particularly for lacerations over joints, is necessary. In general, excessive wrapping should be avoided, however, to prevent complete immobilization of a moving anatomic part, particularly the hand. Although rest for the injury is necessary, some movement is encouraged within the bandage. The goal is to prevent the stiffening of joints that can occur, especially in elderly patients.
Young children present a particularly difficult challenge in wound dressing. Their wounds heal rapidly and, in practice, seem to be resistant to infection. The principle of simplicity is important. A Band-Aid, when it can be used appropriately, is the dressing of choice for small wounds. If the Band-Aid is removed by the child, it can be replaced easily by the parent. Children are more likely to leave Band-Aids in place, because this dressing is recognized as a “badge” for other children to appreciate. When more complicated dressings have to be used on the hand, a “mitten-like” bandage that encompasses the entire hand is often recommended. If the laceration or wound is serious, older children generally seem to have an instinctive understanding that prevents them from removing dressings.
Basic Wound Dressings
Unbandaged Wounds: Topical Antibiotics
Topical antibiotic ointments are currently recommended for facial wounds (e.g., lacerations, abrasions, burns) or any other wound, such as an abrasion, that is treated without bandaging. These ointments provide a moist wound healing environment in the absence of a bandage. They also reduce dry exudate, or scab, formation, which makes suture removal much easier. Suppression of infection and improved wound edge healing, particularly for flaps, are reasons to support the use of topical agents. In an evidence-based review of the application of ointment to lacerations and other small wounds, however, all of the cited studies had significant weaknesses. The question of whether ointment reduces wound infection remains unanswered.
Topical ointments should be thinly applied two to three times daily to maintain consistent coverage. Petrolatum-based antibacterial ointments (e.g., polymyxin B sulfate/neomycin [Neosporin] and silver sulfadiazine [Silvadene]) have been shown experimentally to encourage epithelialization effectively as compared with other ointments (e.g., nitrofurazone [Furacin] and Pharmadine, which contains povidone-iodine). Neosporin is easier to apply to the face than silver sulfadiazine, which needs to be applied in a thick layer. Other agents that can be used for this purpose are polymyxin B sulfate/bacitracin (Polysporin) and zinc salt/polymyxin/neomycin (Bacitracin). If a patient is known to be sensitive to neomycin, plain petrolatum ointment can be used. Petrolatum-based topical antibiotic ointments should not be used on wounds closed with wound adhesive. The petrolatum will soften and disrupt the adhesive.
The basic wound covering consists of four materials:
Absorbent gauze sponges (gauze wrapping if needed)
Tape to secure the dressing
After repair, an antibacterial ointment can be thinly and gently spread over the wound. Based on the preceding discussion, application of a topical agent for sutured lacerations can be considered optional. The main use of these ointments under bandages is to lessen dry exudate formation and to add to the moist environment of the dressing. Ointments can be applied at each bandage change. Neosporin, Polysporin, and Bacitracin are commonly used.
In a sterile fashion, the nonadherent base is cut to conform with the general wound area ( Fig. 20-2 ). Depending on the potential for wound drainage and exudation, gauze sponges are placed over the base. On an extremity, a gauze wrap is applied, followed by tape. On flat surfaces where gauze wrapping is not appropriate, the tape is placed directly over the gauze sponges.