We discuss the recognition and treatment of necrotizing fasciitis.

Hosts:

Aurnee Rahman, MD

Brian Gilberti, MD

https://media.blubrry.com/coreem/content.blubrry.com/coreem/Necrotizing_Fasciitis.mp3



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Tags: Critical Care, General Surgery





Show Notes
Table of Contents

0:00 – Introduction

0:41 – Overview

1:10 – Types of Necrotizing Fasciitis

2:21 – Pathophysiology & Risk Factors

3:16 – Clinical Presentation

4:06 – Diagnosis

5:37 – Treatment

7:09 – Prognosis and Recovery

7:37 – Take Home points

Introduction

• 
  
• Necrotizing soft tissue infections can be easily missed in routine cases of soft tissue infection.
  
• High mortality and morbidity underscore the need for vigilance.
  

Definition

• 
  
• A rapidly progressive, life-threatening infection of the deep soft tissues.
  
• Involves fascia and subcutaneous fat, causing fulminant tissue destruction.
  
• High mortality often due to delayed recognition and treatment.
  

Types of Necrotizing Fasciitis

• 
  
• Type I (Polymicrobial)
  
  • 
    
  • Involves aerobic and anaerobic organisms (e.g., Bacteroides, Clostridium, Peptostreptococcus).
    
  • Common in immunocompromised patients or those with comorbidities (e.g., diabetes, peripheral vascular disease).
    
  
  
  
• Type II (Monomicrobial)
  
  • 
    
  • Often caused by Group A Streptococcus (Strep pyogenes) or Staphylococcus aureus.
    
  • Can occur in otherwise healthy individuals.
    
  • Vibrio vulnificus (associated with water exposure) is another example.
    
  
  
  
• Fournier’s Gangrene (Subset)
  
  • 
    
  • Specific to perineal, genital, and perianal regions.
    
  • Common in diabetic patients.
    
  • Higher mortality, especially in females.
    
  
  
  

Pathophysiology

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• Spread Along Fascia
  
  • 
    
  • Poor blood supply in fascial planes allows infection to advance rapidly.
    
  • Tissue ischemia worsened by vascular thrombosis → rapid necrosis.
    
  
  
  
• High-Risk Patients
  
  • 
    
  • Diabetes with vascular compromise.
    
  • Recent surgeries or trauma (introducing bacteria into deep tissue).
    
  • Immunosuppression (e.g., cirrhosis, malignancy, or immunosuppressive meds).
    
  • NSAID use may mask symptoms, delaying diagnosis.
    
  
  
  

Clinical Presentation

Early Signs & Symptoms

• 
  
• Severe Pain out of proportion to exam findings.
  
• Erythema (often with indistinct borders).
  
• Fever, Malaise (systemic signs of infection).
  
• Rapid progression with possible color changes (red → purple).
  
• Bullae Formation (fluid-filled blisters) and skin necrosis/gangrene.
  
• Crepitus in polymicrobial cases (gas production in tissue).
  

Late-Stage Signs

• 
  
• Systemic toxicity: hypotension, multi-organ failure if untreated.
  

Diagnosis

• 
  
• Clinical Suspicion Is Key
  
  • 
    
  • Pain out of proportion, rapid progression, systemic signs.
    
  • The “finger test” (small incision to explore fascial planes).
    
  
  
  
• Surgical Consultation
  
  • 
    
  • Early surgical exploration is often the definitive diagnostic step.
    
  
  
  
• Lab Tests
  
  • 
    
  • LRINEC Score (CRP, WBC, Hemoglobin, Sodium, Creatinine, Glucose) to stratify risk.
    
  • Not definitive but can guide suspicion.
    
  
  
  
• Imaging
  
  • 
    
  • CT scan may reveal gas in tissues, fascial edema, or muscle involvement.
    
  • Must not delay surgical intervention if clinical suspicion is high.
    
  
  
  

Treatment Principles

• 
  
• Immediate & Aggressive Surgical Debridement
  
  • 
    
  • Often multiple surgical procedures are required as necrosis progresses.
    
  • Debridement back to healthy tissue margins.
    
  
  
  
• Empiric Broad-Spectrum Antibiotics
  
  • 
    
  • Cover gram-positive (including MRSA), gram-negative, and anaerobes.
    
  • Examples include:
    
    • 
      
    • Vancomycin or Linezolid (for MRSA).
      
    • Piperacillin-tazobactam or Carbapenems (for gram-negative & anaerobes).
      
    • Clindamycin (to inhibit bacterial toxin production).
      
    
    
    
  • Adjust based on culture results later.
    
  
  
  
• Adjunct Therapies
  
  • 
    
  • Hyperbaric Oxygen Therapy (if available) for resistant cases.
    
  • Evidence is mixed; not universally accessible.
    
  
  
  
• Supportive Care
  
  • 
    
  • Intensive monitoring, often in an ICU setting.
    
  • Fluid resuscitation & vasopressors for septic shock.
    
  
  
  

Prognosis & Disposition

• 
  
• High Mortality Rate
  
  • 
    
  • Influenced by infection site, patient’s baseline health, and speed of intervention.
    
  
  
  
• Importance of Rapid Intervention
  
  • 
    
  • Early recognition, aggressive surgery, and antibiotics improve survival.
    
  
  
  
• Long-Term Considerations
  
  • 
    
  • Patients may require extensive rehabilitation.
    
  • Reconstructive surgery often needed for tissue deficits.
    
  
  
  
• Disposition
  
  • 
    
  • Operative management is mandatory; patients do not go home.
    
  • Critical care admission is typical for hemodynamic monitoring and support.
    
  
  
  

Five Key Take-Home Points

• 
  
• High Suspicion Saves Lives: Recognize severe pain out of proportion as a critical red flag.
  
• Know Your NF Types & Risk Factors: Type I polymicrobial vs. Type II monomicrobial, plus subsets (Fournier’s).
  
• Clinical Diagnosis Above All: LRINEC and imaging help, but timely surgical exploration is paramount.
  
• Combined Surgical & Medical Therapy: Early debridement + broad-spectrum antibiotics (including toxin inhibition) is lifesaving.
  
• Extended Recovery & Mortality Risks: High mortality if missed or delayed. Expect prolonged rehab and possible multiple surgeries.
  

Resources & Further Reading

• 
  
• LRINEC Score Calculator 
  
• EMCrit – Necrotizing Fasciitis
  

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