This month's continuing education article on "Reducing Postsurgical Wound Complications: A Critical Review," page 272, gives the opportunity to reflect on operative wound healing following a surgical incision, with the theme of surgical site infections (SSIs).
Primary Intention
By the mid-19th century, the formation of pus was considered an inevitable consequence of surgery, but not part of the healing process. Surgery that healed without pus was described as "healing by first intention." Surgeons distinguished between creamy white or yellow laudable pus7 and the bloody, watery, foul-smelling "malignant pus" that indicated pyemia, which was often followed by death.
Today, immediate postoperative closure of the wound is simply called "primary wound closure." Closure of a "clean wound" is typically accomplished by a primary closure technique in healthy patients undergoing an uncontaminated laceration repair, closure of a biopsy, plastic reconstructive surgery, or closure of a clean surgical wound. The wound is usually closed by using sterile techniques with sutures or synthetic adhesive closure materials. The goal is to have an operative closure that creates a functional scar with complete healing. However, there is only a small window of opportunity to close the wound by primary intention, usually 4 to 8 hours. An additional factor is the ability of the clinician to approximate the wound edges. If it is not possible to exact functional wound closure because of the wound structure, nonlinear margins, asymmetrical dimensions, or the potential of interfering with the function of a joint, wound closure may be delayed and require the expertise of a plastic surgeon or a specialized orthopedic surgeon. Other reasons for wound closure delay include contamination or simply a significant lapse of time. In these cases, healing by secondary intention is the next best option.
Secondary Intention
Most incised surgical wounds will heal by primary intention, but some must heal by secondary intention, usually because the wound has been deliberately left open as a delayed primary closure staging technique. It is not uncommon for the wound margins to dehisce because of high wound margin tension, especially over joints where there is a significant functional range of motion, such as in the fingers, wrist, elbows, knees, and hips.
The incidence of surgical wound dehiscence (SWD) is not insignificant. The occurrence of SWD following different surgical procedures has been reported to range between 1.3% and 9.3%.1 According to the Centers for Disease Control and Prevention, an SWD can be superficial or due to deep tissue injury and can be associated with SSI.2,3 Chetter et al4 recently found that more surgical wounds healing by secondary intention (SWHSIs) were being treated in the community (109/187 [58.3%]) than in secondary (56/187 [29.9%]) care settings. Most patients (164/187 [87.7%]) had 1 SWHSI, and the median duration of a wound was 28.0 days (95% confidence interval, 21-35 days). The most common surgical specialties associated with SWHSI were colorectal (80/187 [42.8%]), plastic (24/187 [12.8%]), and vascular (22/187 [11.8%]). Nearly half of SWHSIs were planned to heal by secondary intention (90/187 [48.1%]), and 77 of 187 (41.2%) were wounds that had dehisced. Dressings were the most common single treatment for SWHSI, received by 169 of 181 patients (93.4%). Eleven patients (6.1%) received negative-pressure wound therapy.4
Patients who are medically unstable, have wounds that are contaminated or infected, or have secondary wound dehiscence are candidates for tertiary intention of wound closure.
Tertiary Wound Closure
Tertiary intention (delayed primary closure) occurs when a wound is initially left open after debridement of all nonviable tissue. Wound edges may be surgically approximated following a period of open observation, when the wound appears clean and there is evidence of good tissue viability and tissue perfusion.4-6 Tertiary intention can also refer to subsequent surgical repair of a wound initially left open or not previously treated. This method is indicated for infected or detrimental wounds with high bacterial content, wounds with a lengthy time lapse since injury, or wounds with a severe crush component.6
Advances in wound technology, such as negative-pressure wound therapy, have provided an array of options in facilitating wound management. As part of delayed or tertiary closure in military surgical practice, free flaps and rotational flaps are used to provide soft tissue coverage, along with the innovation of secondary intention wound granulation through vacuum-assisted closure dressings and hemostatic bandages.7
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