Necrotising fasciitisFlesh eating bacteria

- Surgical emergency -

by Yapa Wijeratne

Faculty of MedicineUniversity of Peradeniya Sri Lanka

Necrotizing fasciitis

Infection of subcutaneous tissue-> destruction of fascia and fat

Rapidly progressive bacterial infection Pain, erythema edema, fever->severe pain

with limb swelling->high fever, bluish discoloration & blisters Gangrene and & muscle necrosis

1. Oedema beyond area of erythema2. Crepitus3. Skin blistering4. Fever (often absent)5. Greyish drainage (‘dishwater pus’)6. Pink/orange skin staining7. Focal skin gangrene (late sign)8. Final shock, coagulopathy and multiorgan failure

Sign of necrotising infections

Polymicrobial, synergistic infection – Most commonly a streptococcal species (group aβ

haemolytic) in combination with Staphylococcus, Escherichia coli, Pseudomonas, Proteus, Bacteroides or Clostridium; 80% have a history of previous trauma/infection over 60% commence in the lower extremities.

Causes

1. Diabetes2. Smoking3. Penetrating trauma4. Pressure sores5. Immunocompromised states6. Intravenous drug abuse7. Skin damage/infection (abrasions, bites & boils)

Predisposing conditions

Febrile and tachycardic (early stages) Very rapid progression to septic shock. Oedema stretching beyond visible skin erythema, Disproportionate pain in relation to the affected area Skin vesicles Palpation

◦ A woody hard texture to the subcutaneous tissues,◦ An inability to distinguish fascial planes & muscle groups◦ Soft-tissue crepitus.

Lymphangitis tends to be absent.

Classical clinical signs

Radiographs : air in the tissues Diagnosis: on the basis of symptoms and signs

without recourse to ‘screening radiography’ unnecessary delay may be lethal.

1. Urgent fluid resuscitation,2. Monitoring of haemodynamic status 3. High-dose broad-spectrum IV antibiotics.4. Surgical debridement- diseased area should be

debrided ASAP until viable, healthy, bleeding tissue is reached.

Mx

Advisable,◦ Early review in the operating theatre ◦ Further debridement◦ Use vacuum-assisted dressings.

Early skin grafting - may minimise protein and fluid losses.

Mortality 30–50%

Case 76 yr old H/w from Kandy presented with swelling of the left LL for

5days. She was apparently well before & developed mild fever with left leg pain. Leg pain was severe, resting type, not radiating, persistent throughout the day, & not responding to the PCM. Swelling was developed with redness & accidental trauma has ulcerated the causing discharge. She was admitted to the local hospital on 3rd day but no surgical intervention was made. 5th day after onset of symptoms she was transferred to THK.

She has had STEMI 1yr ago. No Diabetes mellitus. On admission she was afebrile, haemodynamically stable.

Examination of CVS, RS, abdomen & NS clinically normal. WBC 29k/ul ↑↑ Urea 125 mg/dl (10-50) ↑↑ SE, RBC, Hb, PLT, RBS normal. ECG: sinus arrythmia, p mitrale ECHO revealed EF 45% impaired LV function with diastolic

dysfunction. G II MR+ AR+

Spinal anesthesia given. Indurated upto mid thigh. Able to move toes. Skin

necrosis +. Pulse – difficult to feel. Necrotized tissue excised. Underlying fascia split.

Underlying muscle viable.

Necrotising fasciitis

1. NBM2. QHT3. Input/ output chart4. Elevate footend5. > 3 ʘ N/s IV6. 2 ʘ Hartmann7. IV meropenem 500mg bd8. Tramadol 50 mg tds9. Domperidone 10mg bd10. IM Pethidine 75 mg SOS11. IM Phenagan 25 mg SOS12. Monitor PR/ RR/ BP 1 hrly

Post-op