Assessment

see also Surgical Infection

Steps of the Procedure

The following section focuses on operative steps of surgical infection management, from least to most invasive. These include simple incision and drainage of superficial infections, wide debridement of necrotizing infections, abscess drainage using interventional radiology and minimally invasive surgical techniques, and finally open, invasive operations such as exploratory laparotomy to address a perforated viscus.

When cellulitis and induration do not respond to antibiotics, a wound exploration is needed. In children, this typically requires some form of sedation and may be performed in the operating room. For primary infections, such as soft tissue abscesses, the procedure involves an incision over the most fluctuant aspect of the wound, evacuation of any purulent material, and debridement of necrotic tissue. The wound can be packed with a wet to dry dressing. Alternatively, a gauze wick can be placed or a Penrose drain or ilastic loops can be left in place which do not require dressing changes which can be problematic in young children.

The procedure includes removal of the adhesives such as Dermabond®, sutures, and rarely, staples. The wound should be opened adequately to allow for thorough inspection, drainage of purulent material, irrigation to decrease bacterial colonization, and the debridement of nonviable tissues. In addition, myofascial planes can be examined to assure that the infection remains superficial and that there are no signs of necrotizing fasciitis. Once debrided, the wound can be managed with a wet to dry packing or commercially available vacuum assisted closure devices [1].

groin infection

Soft tissue infection due to methicillin resistant staphlycoccal aureus.

thigh abscess

Incision and drainage of a thigh abscess due to methicillin resistant staphylcoccal aureus.

negative pressure therapy

Temporary wound managment with vacuum assisted closure following debridement of superficial wound infection.

While these wounds can be left to close by secondary intention, closure and cosmesis may be improved by a delayed primary closure once the infection has resolved and the pathogenic organisms have been treated. Clinical improvement and stabilization of the patient, resolution of cellulitis or wound drainage and formation of granulation tissue all indicate treatment success with the potential for delayed primary closure. The latter technique has been well described in surgery since at least the early 1900s [2]. With the advent of newer antibiotics and additional antiseptic techniques, primary closure has become more prominent leading to the decreased use of delayed closure. In cases of resolving wound infection, this approach minimizes dressing changes which can be traumatic for children. To date, data on efficacy of either approach in children is lacking.

If a necrotizing infection is suspected, prompt surgical debridement is required. These infections ofter necessitate extensive tissue excision, resulting in large wounds, which ultimately need complex reconstruction. Any necrotic soft tissue, muscle, and sometimes viscera, need to be removed. Wounds are left open and frequently reassessed. Patients with necrotizing fasciitis often need frequent (i.e. daily) wound debridement in the initial phases of care [3].

Intra-abdominal deep space infections, such as abscesses resulting from perforated appendicitis or ulcer disease, or inflammatory bowel disease, can often be managed in conjunction with interventional radiology (IR). At times, IR drain placement is the only therapy required. Many of these infectious processes, however, may require definitive surgical management, such as appendectomy or bowel resection with or without diversion. If the initial approach was operative, up to 30% of patients with a perforated viscus can develop postoperative intra-abdominal abscess [4]. In cases of perforated appendicitis, this rate has decreased significantly over the last decade, with the most recent data showing national abscess rates well under 10% [5]. Percutaneous abscess drainage using IR techniques is an ideal option for these patients, thereby minimizing the risk of re-exploration while the peritoneal cavity is the most hostile. The following patient developed multiple, complicated abscesses after colonic perforation secondary to severe hemolytic uremic syndrome. He was initially diverted with a colostomy and his abscesses were subsequently managed with two IR guided drains.

intra-abdominal abscess

Abscess amenable to percutaneous drainage guided by interventional radiology.

In its most emergent form, operation provides immediate control of deep space infections, secondary to viscus perforations, bowel ischemia, necrotizing enterocolitis or empyema. In terms of infection management, these operations focus on immediate control of the source of sepsis with plans for further definitive therapy once the patient has stabilized. In cases of ischemic or necrotic bowel, this involves an enterectomy often with plans for a "second look operation" within 24 to 48 hours. Only clearly ischemic/necrotic bowel should be removed to preserve bowel length. The unstable patient may require temporary wound closure, (e.g. vacuum-assisted closure system or a silastic silo).

Intraoperative Decision Making

As many of the patients with surgical infections present with hemodynamic instability, many of the intraoperative decisions focus on the extent and duration of the operation, the need for fecal diversion, and a discussion of partial or complete wound closure.

In summary, the unstable patient is treated with expeditious source control, removal/closure of perforation, irrigation and drainage, with prompt return to an intensive care unit setting for ongoing resuscitation and hemodynamic stabilization. Patients who are more stable may undergo a more definitive operation, including anastomoses (if indicated), the creation of ostomies (when needed), and fascial wound closure.

References