Introduction Necrotizing fasciitis is a life threatening infection that spreads along soft tissue planes Risk factors immune suppression diabetes AIDS cancer bacterial introduction IV drug use hypodermic therapeutic injections insect bites skin abrasions abdominal and perineal surgery other host factors obesity Associated conditions cellulitis overlying cellulitis may or may not be present Prognosis life threatening infection mortality rate of 32% mortality correlates with time to surgical intervention Classification Necrotizing Fasciitis Classification Type Organism Characteristics Type 1 Polymicrobial Typical 4-5 aerobic and anaerobic species cultured: • non-Group A Strep• anaerobes including Clostridia• facultative anaerobes• enterobacteria• Synergistic virulence between organisms • Most common (80-90%) • Seen in immunosuppressed (diabetics and cancer patients) • Postop abdominal and perineal infections Type 2 Monomicrobial • Group A β-hemolytic Streptococci is most common organism isolated • 5% of cases • Seen in healthy patients • Extremities Type 3 Marine Vibrio vulnificus (gram negative rods) • Marine exposure Type 4 MRSA Presentation Symptoms early localized abscess or cellulitis with rapid progression minimal swelling no trauma or discoloration late findings severe pain high fever, chills and rigors tachycardia Physical exam skin bullae discoloration ischemic patches cutaneous gangrene swelling, edema dermal induration and erythema subcutaneous emphysema (gas producing organisms) Imaging Radiographs not required for diagnosis or treatment Differentials Gas gangrene Studies Biopsy indications emergent frozen section can confirm diagnosis in early cases technique take 1x1x1cm tissue sample can be performed at bedside or in operating room surgical intervention should not be delayed to obtain histological findings necrosis of fascial layer microorganisms within fascial layer PMN infiltration fibrinous thrombi in arteries and veins and necrosis of arterial and venous walls LRINEC Scoring system score > 6 has PPV of 92% of having necrotizing fasciitis CRP (mg/L) ≥150: 4 points WBC count (×103/mm3) <15: 0 points 15–25: 1 point >25: 2 points Hemoglobin (g/dL) >13.5: 0 points 11–13.5: 1 point <11: 2 points Sodium (mmol/L) <135: 2 points Creatinine (umol/L) >141: 2 points Glucose (mmol/L) >10: 1 point Treatment Operative emergency radical debridement with broad-spectrum IV antibiotics indications whenever suspicion for necrotizing fasciitis operative findings liquefied subcutaneous fat dishwater pus muscle necrosis venous thrombosis technique hemodynamic monitoring with systemic resuscitation is critical hyperbaric oxygen chamber if anaerobic organism identified antibiotics initial antibiotics start empirically with penicillin, clindamycin, metronidazole, and an aminoglycoside definitive antibiotics penicillin G for strep or clostridium imipenem or doripenem or meropenem for polymicrobial add vancomycin or daptomycin if MRSA suspected amputation indications low threshold for amputation when life threatening
QUESTIONS 1 of 6 1 2 3 4 5 6 Previous Next Sorry, this question is for PEAK Premium Subscribers only Upgrade to PEAK (OBQ10.89) Poor outcomes with necrotizing fasciitis have been associated with which of the following factors? Review Topic QID: 3177 1 Pre-existing cardiac dysfunction 1% (22/3187) 2 Polymicrobial infection 2% (73/3187) 3 Use of hyperbaric oxygen 1% (27/3187) 4 Intravenous drug abuse 1% (35/3187) 5 Delay in time to diagnosis 95% (3022/3187) ML 1 Select Answer to see Preferred Response PREFERRED RESPONSE 5 (OBQ12.136) A 16-year-old male presents to the emergency department one day after scratching his leg on a piece of scrap metal. He reports a progressive rash on his leg that has advanced over the last several hours. In the emergency room his temperature is 102.8 degrees and his systolic blood pressure is 98 mmHg. On physical exam the clinical finding shown in Figure A is found. What would be the most appropriate next step in treatment. Review Topic QID: 4496 FIGURES: A 1 MRI 17% (774/4689) 2 Biopsy with urgent frozen section in the operating room 57% (2681/4689) 3 Needle aspiration 9% (443/4689) 4 CT 9% (428/4689) 5 Ultrasound 7% (334/4689) ML 4 Select Answer to see Preferred Response PREFERRED RESPONSE 2 (OBQ04.217) A 52-year-old diabetic male sustained minor blunt trauma to his left thigh 10 hours prior to presentation. He initially complained of extreme thigh pain with erythema and swelling but rapidly developed bullae and worsening erythema over the affected area along with fever and tachycardia. A clinical photo is shown in Figure A. What clinical factor has been shown to reduce mortality when treating this pathology? Review Topic QID: 1322 FIGURES: A 1 Presence of MRI findings 0% (1/442) 2 Administration of pressors 0% (2/442) 3 Decreasing time from admission to surgery 95% (422/442) 4 Immediate identification of causative organism 2% (10/442) 5 Location of injury 1% (5/442) ML 1 Select Answer to see Preferred Response PREFERRED RESPONSE 3 (OBQ04.264) A 56-year-old diabetic male presents to the emergency department by ambulance after developing high-grade fevers, malaise, and altered mental status. Upon presentation, he is found to be hypotensive and initial labs show an elevated WBC with a profound left shift. Figure A shows skin manifestations confined to the foot at initial presentation. He is started on broad spectrum antibiotics. Upon follow-up exam 3 hours later his clinical condition deteriorates (Figure B) and he is taken to the operating room for surgical debridement. In a bacterial culture, what would be the most common single isolate for this condition? Review Topic QID: 1369 FIGURES: A B 1 Staphylococcus aureus 17% (329/1896) 2 Staphylococcus epidermidis 2% (34/1896) 3 Group A streptococcus 76% (1436/1896) 4 Enterobacteriaceae 1% (18/1896) 5 Pseudomonas 3% (65/1896) ML 2 Select Answer to see Preferred Response PREFERRED RESPONSE 3 Sorry, this question is for PEAK Premium Subscribers only Upgrade to PEAK
Upgrade to View Premium Videos Upgrade to View Premium Videos Necrotizing Fasciitis Treatment Colin Woon Trauma - Necrotizing Fasciitis 11/23/2012 5189 views