Surgery

Treatment

Symptoms and signs

NF typically develops over a few days, but can progress much more rapidly in some cases, eg with infection with Vibrio spp. and A. hydrophila where it may be fatal within 48 hours. The typical development of symptoms and signs is:

Days 1-2 approximately:

· Local pain, swelling and erythema. This mimics cellulitis or erysipelas: the necrotising infection is deep in the skin and not visible (Image 7.6).

· Severe, constant pain, out of proportion to the physical signs, is a notable feature.

· The margins of infection are poorly defined, with tenderness extending beyond the apparent area of involvement (unlike cellulitis).

· There is no response to antibiotics (unlike cellulitis).

· Lymphangitis is rarely seen (unlike cellulitis).

· Systemic illness - malaise, tachycardia ± fever and dehydration. One review suggests that patients often "feel worse than they have ever felt and don't know why."

Days 2-4 approximately:

· The area develops tense oedema, extending beyond the margin of erythema.

· There may be bullae, indicating skin ischaemia (unlike cellulitis). These may become haemorrhagic.

· Skin becomes discoloured, progressing to grey necrosed skin which breaks down (Image 7.7).

· The subcutaneous tissues have a wooden-hard feel (unlike cellulitis or erysipelas). Fascial planes and muscle groups are not palpable.

· There may be crepitus due to subcutaneous gas.

· Pain sensation may progress from intense tenderness to anaesthesia as the nerves are destroyed.

· There may be a broad erythematous tract in the skin along the route of the infection as it advances cephalad.

· If there is an open wound, probing the edges with a blunt instrument produces easy dissection of the superficial fascial planes well beyond the wound margins.

Days 4-5 approximately:

· Hypotension and septic shock develop.

· Patients become confused and apathetic.

The essential treatment is early and aggressive debridement of the involved tissue.

Resuscitation, antibiotics and medical care are also important. Patients may be shocked or haemodynamically unstable.

Urgent surgical debridement is the key factor in treatment and improved survival of NF. Even a few hours' delay increases mortality.

The initial surgery is the most important determinant for survival. The debridement must be extensive, with adequate margins so that no infected tissue remains.

Surgical debridement is repeated daily until the infection is controlled.

When the infection is controlled, daily dressings are required under sedation.

Closure of the wound is by secondary suturing, ± skin grafts. Vacuum-assisted wound closing devices may assist healing.

Дата добавления: 2014-10-15