Necrotizing Fasciitis BY Hosam Mohammad Hamza, Msc

GENERAL SURGEON & ENDOSCOPISTMINIA FACULTY OF MEDICINE

MINIA- EGYPT

Outline• Definition • Causes.• Pathophysiology.• Clinical features.• Diagnosis• D.D.• Complications.• Treatment

Definition A progressive life-threatening soft-

tissue infection (with liquifactive necrosis of subcutaneous fat and

fascia) ± skin .  Cheng NC, Su YM, Kuo YS, Tai HC, Tang YB. Fa

ctors affecting the mortality of necrotizing f asciitis involving the upper

 extremities. Surg Today   -. 2008;38(12):110813.

Early reports date back to the 5th century B.C. , when Hippocrates described a

complication of erysipelas.The term “ necrotizing fasciitis” was first

used on 1952

Causes• Surgery may induce local tissue injury and

bacterial invasion (e.g. intraperitoneal or perianal abscesses)

• Trauma.

• IM injections.

• Local hypoxia with systemic illness (immunosuppression or DM compromise of the fascial blood supply) Schwartz’s principles of surgery, 9th

ed.

• A possible relationship between the use of NSAIDs (as ibuprofen) and development of necrotizing fasc

iitis during varicella infections has been shown. Zerr DM, Alexander ER, Duchin JS, et al. A

case-control study of necrotizing fasciitis during primary

varicella. Pediatrics. Apr 1999;103(4 Pt 1):783-90.

Idiopathic necrotizing fasciitis

• No obvious portal of entry.• typically involves genetalia (Fourniere Gangrene) or lower

extremities.• caused by single organism (e.g.

Strep. pyogenes)• May be due to unrecognized breaks in skin or hematogenous

spread

Pathophysiology• 1ry site of pathology is the superficial

fascia.

• Surgery / Trauma tissue hypoxia PMNL dysfunction good environment for facultative aerobes more ↓ oxidation proliferation of anaerobic bacteria angiothrombotic microbial invasion

liquefactive necrosis

• Microbiology: - Group A haemolytic streptococci.

- Staph. Aureus. - Others : Bacteroides, Clostridium, and (Vibrio

vulnificus often in chronic liver D.) - Fungi (Rare and less aggressive forms)SCH

• Aerobic metabolism Co2 + H2O. • Anaerobic metabol. H, N, H2S.

Type I- Polymicrobial (aerobic and anaerobic)- Common with DM and PVD, after surgical

procedures

Type II- Monomicrobial (primarily by GAS,

occasionally caused by community-associated MRSA).

Clinical features♂ : ♀ ratio = 2-3 : 1, adult or elderly. History of recent trauma or surgery. sudden onset of pain and swelling.

hours to days

anaesthesia. Early Diagnosis can be challenging as physi

cal findings may be out of proportion with degree of patient discomfort (high degree of

suspicion is mandatory).

Physical findings

• Toxaemia (esp. late)• area of erythema quickly spreads into

normal skin without sharp demarcation

dusky or purplish skin multiple identical patches of

gangrenous skin

- large area of skin gangrene.- Bullae with putrid discharge.- Local crepitus (infrequent)- Fascial necrosis.- Without ttt myonecrosis.

- Fever.- Shock.- MOF

Important distinguishing features: (SABISTON’S TEXTBOOK OF SURGERY)

- wooden hard feel of subcutaneous Tissue. while yeilding in cellulitis and erysipelas.- If an open wound probing allows easy

dissection of superficial fascial planes beyound wound margins with little pain.

CLINICAL STAGES OF NECROTISING FASCIITIS

A. This patient developed pain on moving the rt hip with cellulitis 2 weeks after total colectomy.

B. Cellulitis didn’t respond to medical ttt, and surgery was done showing dishwater oedema of sc tissue.

C. Muscles were viable.Source: Brunicardi FC, Andersen DK,

Billiar TR, Dunn DL: Schwatrz’s Principles of Surgery. 9th ed. All rights reserved

Can affect any part of body

• Perineum: - neglected ischiorectal/perineal abscess.• Vulva:- Bartholin’s gland duct abscess- vulvar abscess- post-op wound infection from C-section or

episiotomy.• Fourniere gangrene: - GU infection or surgery. - traumatic instrumentation

- Scalp/Periorbital: trauma, eyelid infections.- Face/Neck: progressive dental infections,

peritonsillar abscess, salivary gland infections, cervical adenitis, otologic sources

- Trauma- drug abuse- insect bites (rare).

post-op complication of abd surgery Complication of percutaneous catheter placement:

chest tube or percutaneous drain of abd. abscess

DiagnosisIt is mainly a Clinical Diagnosis.LAB: LRINECLab Risk Indicator for NECrotizing fascii.

> 6 should raise suspicion of NF

> 8 is highly predictive of NF Imaging

PARAMETER POINTS

CRP > 150 mg/L 4

Leucocytosis 15 – 25 X 103> 25 X 103

12

Hb 11 – 13 g%< 11 g%

12

Serum Na < 135 Meq / L 2

Serum Glucose > 180 mg % 1

PLAIN X RAY of an established case of necrotizing fasciitis of lower limb (stage 3) showing:

1- Soft tissue thickening2- Subcutaneous gas

-acute inflammatory cells in the necrotic tissue.- Bacteria are located in the haziness of their cytoplasm.- Obliterative thrombosis of a,v

• Imaging techniques ( such as MRI ) and frozen section biopsies, have been reported to be of value in early recogniti

on of necrotizing fasciitis. 18101 106 #200Curr Opin Infect Dis : – .

& & &&&&&&&5 & .

D.DClinical Findings

Type 1 Type 2 Gas Gangrene

Pyomyositis

Myositis viral/ parasitic

Fever ++ ++++ +++ ++ ++

Diffuse Pain

+ + + + ++++

Local Pain

++ ++++ ++++ ++ ++

Systemic Toxicity

++ ++++ ++++ + +

Gas in tissue

++ - ++++ - -

Obvious portal of entry

++++ + ++++ - -

DM ++++ + - - -

Complications: - Overall mortality is up to 30% from:• MOF • Septic shock. • Toxic shock syndrome (TSS)- Contributing factors:* Old age. * DM. * Missed early diagnosis.

* Trunkal invol. * Anorectal invol.* Late pres. * Failure after 1st op.File TM, Tan JS. Group A strept. necrotizing

fasciitis.  Compr Ther. 2000;26(2):73-8.

Treatment• Delay in diagnosis and treatment of nec

rotizing fasciitis increases mortality McHenry CR, Piotrowski JJ, Petrinic D, Mal angoni MA. Determinants of mortality in

necrotizing soft tissue infections. Ann Su rg 1995; 221:558–563.

• Aggressive ttt is needed even for suspected cases to reduce mortality.

• ABC.• Antibiotics as soon as possible (aerobic and anaerobi

c bacteria)• Surgery:- Aggressive resuscitation followed by aggressive debrid

ement of all necrotic tissue.- may need to be repeated (careful daily postop inspection). - fasciotomies in extremities.- Amputation for myonecrosis in limbs• Postop use of unprocessed honey- Stimulates epithelialization.- Debrides- Deodourizes wound- DehydratesAkram Rajiput, Waseem Abul Samad, Mortality in

necrotizing fasciitis. J Ayub Med Coll Abbottabad 2008; 20(2)

• IV IG (UNDER STUDY)

• Hyperbaric oxygen therapy (HBO)- Def. = use of 100 % O2 at +++

pressure (3 AP).- ↑ normal O2 saturation in infected

wounds by a thousand fold: bacteriocidal effect.

↑ PMN function ↓ clostridial α toxin production.

enhanced wound healing.

  Mulla ZD. Hyperbaric oxygen in n  ecrotizing fasciitis. Plast

Reconstr Surg  .  Dec 2008;122 (-6):1984 5.

Hyperbaric oxygen therapy

Indications Contraindications

-Air embolism -CO poisoning-Necrotizing soft tissue infections -Gas gangrene -Crush injury-Decompression sickness -Enhancement of healing in selected wounds -Osteomyelitis (refractory) -Compromized skin grafts

- Untreated pneumothorax- Asthma- COPD- Eustachian tube dysfunction- Pregnancy- Claustrophobia

HBO cannot replace surgery. The best outcome is obtained using a combined

approach of antibiotics, surgery, and HBO, when readily available.