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Gangrene, Emergency Medicine

Basics

Description

- Parenteral antibiotic therapy: - Initial empiric therapy should cover Clostridium species and group A Streptococcus as well as mixed aerobes and anaerobes - Primary definitive therapy: Penicillin G + clindamycin - Alternative: Ceftriaxone or erythromycin - If mixed infection: Penicillin + clindamycin, metronidazole, or vancomycin and gram-negative coverage with gentamicin - Follow local sepsis protocols

  • Gas gangrene or clostridial myonecrosis
  • An acute, rapidly progressive, gas-forming necrotizing infection of muscle and subcutaneous tissue
  • Can be seen in post-traumatic or postoperative situations
  • Progressive invasion and destruction of healthy muscle tissue

Etiology

  • Clostridial organisms:Facultative anaerobic, spore-forming, gram-positive bacillusProduces a number of toxins; the most prevalent and lethal is α-toxin.
  • Clostridium perfringens is the most common bacterium; found in 80-90% of wounds.
  • Other clostridial bacteria include Clostridium novyi, Clostridium septicum, Clostridium histolyticum, Clostridium bifermentans, and Clostridium fallax.
  • 2 distinct mechanisms for introduction of clostridial organisms:Traumatic and postoperativeNontraumatic associated with diabetes mellitus, peripheral vascular disease, alcoholism, IV drug abuse, and malignancies

Diagnosis

Signs and Symptoms

  • Sudden severe pain of extremity or involved area
  • Low-grade fever
  • Tachycardia out of proportion to fever
  • Bronzing of the skin over involved area; later can turn purple or red
  • Crepitus
  • Formation of blebs and bullae
  • Thin, serosanguinous exudate and sweet odor
  • Rapid local extension
  • Obtunded sensorium
  • Systemic toxicity

Essential Workup

  • History and physical exam with special attention to clinical evidence of crepitus in soft tissue
  • Soft tissue x-rays of involved area to detect gas dissecting along fascial planes:The absence of gas does not exclude significant disease.
  • Stat Gram stain of wound exudate for gram-positive bacillus with paucity of leukocytes

Diagnosis Tests & Interpretation

Lab

  • CBC with differential, electrolytes, BUN, and creatinine
  • Coagulation studies
  • Evaluate for hemolysis
  • Stat Gram stain of wound exudates
  • Anaerobic cultures of wound or tissue biopsy

Imaging

  • Radiographs may reveal soft tissue gas.
  • CT if area involves abdomen or flank.

Diagnostic Procedures/Surgery

All patients with gas gangrene must undergo surgical d ©bridement.

Differential Diagnosis

  • Cellulitis
  • Necrotizing fasciitis
  • Nonclostridial myositis and myonecrosis
  • Other causes of gas in tissues, as from dissection from respiratory or GI tracts

Treatment

Pre-Hospital

Establish IV and infuse isotonic fluids

Initial Stabilization/Therapy

Manage airway and resuscitate as indicated:

  • Rapid sequence intubation as needed.
  • Supplemental oxygen:Cardiac and oxygen saturation monitors should be placed.
  • IV access; consider central venous pressure monitoring; sepsis protocol is appropriate
  • Aggressive volume expansion, including crystalloid, plasma, packed RBCs, and albumin if there is septic shock.

Ed Treatment/Procedures

  • Parenteral antibiotic therapy:Initial empiric therapy should cover Clostridium species and group A Streptococcus as well as mixed aerobes and anaerobesPrimary definitive therapy: Penicillin G + clindamycinAlternative: Ceftriaxone or erythromycinIf mixed infection: Penicillin + clindamycin, metronidazole, or vancomycin and gram-negative coverage with gentamicinFollow local sepsis protocols
  • Surgical consultation:D ©bridement, amputation, or fasciotomy is required.
  • Hyperbaric oxygen (HBO) as adjunctive therapy:Early transfer to hyperbaric facility may be lifesaving.Lack of randomized trials with HBO but nonrandomized studies suggest benefit
  • Tetanus prophylaxis
  • Observe for major complications including ARDS, renal failure, myocardial irritability, and DIC.
  • Polyvalent antitoxin is not made in US and studies have not demonstrated efficacy:Because of the unacceptable hypersensitivity reactions, it is not routinely recommended.

Medication

  • Ceftriaxone: 2 g (peds: 100 mg/kg/24h max. 4 g) IV q12h
  • Clindamycin: 900 mg (peds: 40 mg/kg/d q6h) IV q8h
  • Erythromycin: 1 g (peds: 50 mg/kg/d q6h) q6h IV
  • Gentamicin: 2 mg/kg (peds: 2 mg/kg IV q8h) IV q8h
  • Metronidazole: 500 mg (peds: Safety not established) IV q8h
  • Penicillin G: 24 million IU/24h (peds: 250,000 IU/kg/24h) IV q4-6h
  • Tetanus immune globulin: 500 IU IM
  • Tetanus toxoid: 0.5 mg IM

First Line

Primary definitive therapy for clostridial species; combination of penicillin G and clindamycin

Follow-Up

Disposition

Admission Criteria

  • All patients with gas gangrene and evidence of myonecrosis must be admitted for surgical d ©bridement and IV antibiotics.
  • Use of HBO therapy is an important adjunct.

Discharge Criteria

No patient with acute gangrene should be discharged.

Issues for Referral

After stabilization with antibiotics and surgical d ©bridement, consider referral for HBO treatment as an adjunct.

Pearls and Pitfalls

  • Bacteremia occurs in about 15% and can progress quickly to intravascular hemolysis.
  • HBO as adjunctive therapy to surgical d ©bridement and early antibiotics if patient is hemodynamically stable

Additional Reading

  • Bakker DJ. Clostridial myonecrosis (gas gangrene). Undersea Hyperb Med. 2012;39(3):731-737.
  • Bryant AE, Stevens DL. Clostridial myonecrosis: New insights in pathogenesis and management. Curr Infect Dis Rep. 2010;12(5):383-391.
  • Headley AJ. Necrotizing soft tissue infections: A primary care review. Am Fam Physician. 2003;68(2):323-328.
  • Pinzon-Guzman C, Bashir D, McSherry G et al. Clostridium septicum gas gangrene in a previously healthy 8-year old female with survival. J Pediatr Surg. 2013;48(4):e5-e8.
  • Stevens DL, Aldape MJ, Bryant AE. Life-threatening clostridial infections. Anaerobe. 2012;18(2):254-259.

Codes

ICD9

  • 040.0 Gas gangrene
  • 785.4 Gangrene

ICD10

  • A48.0 Gas gangrene
  • I96 Gangrene, not elsewhere classified

SNOMED

  • 372070002 Gangrenous disorder (disorder)
  • 80466000 Gas gangrene (disorder)
  • 266093005 Gas gangrene caused by clostridium perfringens (disorder)
  • 266091007 Gas gangrene caused by clostridium histolyticum (disorder)