Abdominal Wall Dehiscence

Abdominal wall dehiscence is partial or complete separation of a previously closed abdominal surgical wound. It may involve only skin and subcutaneous tissues or extend through the fascial layer.

Fascial separation is the clinically dangerous form because bowel may herniate through the defect and progress to obstruction, strangulation or evisceration.

Risk rises with surgical site infection, emergency laparotomy, malnutrition, diabetes, corticosteroid exposure, renal failure, severe sepsis, obesity, prolonged ileus, repeated coughing and poor fascial closure.

Most acute fascial failures occur during the first one to two postoperative weeks when the wound has minimal intrinsic tensile strength.

Superficial dehiscence presents with separation of the skin edges without loss of fascial integrity.

Fascial dehiscence should be suspected with:

• Sudden increase in wound drainage
• Serous or serosanguineous fluid from the incision
• New bulging beneath the wound
• A reported popping or tearing sensation after coughing or straining
• Visible or palpable fascial separation
• Associated wound infection

Do not assume an intact skin closure means the fascia beneath it remains intact.

If fascial disruption is obvious, diagnosis is clinical.

CT abdomen and pelvis with contrast: useful when the fascia is suspected to have separated but the skin remains intact; defines the defect, herniated bowel and associated abscess or intra abdominal pathology.

Do not routinely remove intact skin sutures or staples at the bedside merely to inspect the fascia. Opening the wound can convert a contained fascial defect into evisceration.

Superficial skin separation with intact fascia is managed with wound care, treatment of infection and secondary closure or healing by secondary intention according to contamination and tissue quality.

Fascial dehiscence requires urgent surgical assessment.

A stable patient with a small fascial defect, intact overlying skin, no obstruction, no strangulation and no infection may occasionally be managed nonoperatively as a controlled incisional hernia. This is highly selective.

Operate for:

• Evisceration
• Bowel obstruction through the defect
• Suspected strangulation or ischaemia
• Infected fascial dehiscence requiring source control
• Progressive or large fascial disruption

At operation, inspect bowel viability and identify infection or intra abdominal pathology. Debride clearly nonviable fascia and tissue.

If fascia is healthy and can be approximated without dangerous tension, primary fascial reclosure is appropriate.

Gross infection, major tissue loss, severe oedema or inability to close without excessive tension may require temporary abdominal closure and delayed definitive reconstruction.

Treat the underlying factors simultaneously: drain infection, control coughing and vomiting, decompress ileus, optimise nutrition and correct major metabolic abnormalities.