Clinical Case. ! 2am: Call from Surgeon, Ballarat Hospital. ! Suspicion of Necrotizing Fasciitis: ! Need of HBOT?

Transcription

1

2 Clinical Case! 2am: Call from Surgeon, Ballarat Hospital! Suspicion of Necrotizing Fasciitis:! 59y, Police Officer, diabetic, overweight! 4pm: pain in right arm! 8pm: pain worsening " ED! HD instability " Suspicion of Sepsis and Nec Fas! 10pm: Operating theater " Necrotising fasciitis! Need of HBOT?

3

4 Organisation! Ballarat Surgeon Registrar calls:! 1. Hyperbaric Registrar: Indication of HBOT?! 2. ICU Registrar: Bed availability, Chance of survival! 3. Surgeon: in charge of the patient! Transport organised by road or air.! Hyperbaric team called in (2 nurses, 1 Tech)! ENT: Tympanostomy tubes

5 Arrival at The Alfred: 4am

6 At arrival! Arrival in the ICU:! Resuscitation, ABx! Operating theater: second look/ more debridement if needed.! Post theater, transfer to Hyperbaric Unit: 1 st HBO session at 6:30am.

7 Trauma Center

8 Challenge! Good cooperation and timing between ICU Surgeons HBOT

9 Initial presentation

10 Surgery

11

12 Treatment! 1. Surgery:! Extensive debridement! Daily revision! Perop tissue taken for culture! 2. ICU:! CV/ Ventilatory support, Diabetes management! Management of septic shock! Abx (Alfred s guidelines) : Penicilline, Meropenem, Lincomycin

13 Treatment! 3. HBOT! 3 treatments with Table RN 60.5 during the first 24h! Following days: HBOT twice daily, RN 60.5 until no further progression of the necrosis! Then, routine treatment for wound healing

14 Table 60.5A Attendant on O kpa (9 msw) 180 kpa (18 msw) Duration 1hr 35 min

15 Evolution One month later

16 Evolution One and half month later, after Skin graft

17 Evolution Two months later

18 Evolution One year later

19 Nomenclature! Gas Gangrene (clostridial myonecrosis)! Necrotizing Fasciitis! But also:! Fournier s gangrene, Cullen s progressive bacterial synergistic gangrene, Meleny s ulcer, haemolytic streptococcal gangrene, streptococcal myositis, synergistic necrotising cellulitis, necrotising panniculitis, anaerobic crepitant cellulitis, etc

20 Nomenclature! NSTI: Necrotizing Soft Tissue Infections! NSTI is now the preferred term! Encompasses all infections associated with Necrotizing histological change in any of the layer within the soft tissue compartment! Dermis, subcutaneous tissue, superficial fascia, deep fascia, or muscle! Tissue Gas not required for diagnosis

21 Tissue based classification NSTI s! Skin! Progressive Bacterial Gangrene! Necrotizing cellulitis, clostridial cellulitis! Necrotizing Fasciitis! Including Fournier s! Myonecrosis! Clostridial myonecrosis (Gas Gangrene)! Non clostridial myonecrosis

22 Amsterdam classification! Progressive bacterial gangrene (PBG)! Anaerobic! Clostridial! Non-clostridial! Aerobic! Mixed! Necrotizing fasciitis (NF)! Anaerobic/Aerobic! Mixed! Myositis & myonecrosis! Anaerobic! Clostridial! Non-clostridial (inc. streptococcal)! Others! Aerobes! Viruses! Parasites

23 Organism based Classification Type Aetiology Organism Clinical Mortality Type I (70-80% cases) Polymicrobial, synergistic Mixed Anaerobes and Aerobes Indolent better prognosis Variable depends on comorbidities Type II (20-30%) Monomicrobial skin or throat derived Group A βhaemolytic Strep (GAS) Aggressive Protean presentations >30% if myositis or toxic shock Type III Gram Negative, marine related Vibrio Species Seafood ingestion or wounds 30-40% Type IV (fungal) Trauma related immunocompetent Candida if immunosuppressed, Zygomycetes Aggressive rapid extension >47% higher if immunocompro mised

24 Necrotizing Fasciitis! Progression over hours - days! Deep fascia the primary location! Skin, Muscle, nerves etc, secondary location! Sero-sanguinous - foul pus! Streptococcal or mixed! Mortality 20-75%! Surgery, antibiotics,?hbo

25 Predisposing factors! Diabetes mellitus! Chronic kidney disease! Peripheral vascular disease! Antecedent trauma! Recent surgery! Immunosuppression (medications or HIV)! Malignancy (solid organ or haematological)! Alcoholism +/- chronic liver disease! Injecting drug use

26 Difficulties in making diagnosis! Symptoms! Pain out of proportion to physical findings! Signs! Local hard signs:! Gas on x-ray; tense oedema; purple discoloration; cutaneous Gangrene; bullae! Poor sensitivity: Only 39% had any hard sign! Late: Shock, organ dysfunction! Scoring systems! LRINEC Laboratory Risk Indicator for NSTI

27 Bacteriology NSTI! Wide number of different pathogens reported! Polymicrobial (Type 1) vs. Monomicrobial (Type 2)! Different prevalences, influenced by! Patient characteristics, Geographic region! Changing spectrum! Increase in Streptococcal species! Vibrio vulnificus in tropical coastal locations! Clostridial species outbreaks in IVDU! Increase in community acquired MRSA

28 Antibiotic choice in Anaerobic infections! Often polymicrobial! Fastidious growth! AB choice is often empirical! Increasing resistance! Geographical variation

29 Management! Empirical Antibiotic Therapy Myonecrosis/Necrotising fasciitis! Carbapenem, Benzyl Penicillin, Clindamycin! If MRSA suspected: Vancomycin or Linezolid! If suspect Group A Streptococcal infection: IVIG

30 Oxygen as an antibiotic:! Impairs bacterial metabolism! Improves phagocytosis! Free-radical injury of microorganisms not possessing scavenging mechanisms! Synergistic effect with sulphonamides and aminoglycosides! Enhanced tissue PO 2 for optimal effect of Abx! Direct bacteriostatic effect! Inhibits production or detoxifies exotoxins

31 The Alfred Experience Clostridia Alfred Clostridia Australia Nec Fasc Alfred Nec Fasc Australia Australian Hyperbaric Unit statistics! 16,800 patients ! 53 Clostridial myonecrosis ! 478 Necrotising Fasciitis Alfred ! 13 Clostridial myonecrosis (25%)! 185 Necrotising Fasciitis (55%)

32 Alfred NSTI Jan Feb Mar Apr May June Jul Aug Sep Oct The Alfred Jan Dec 2008! 219 patients HBOT for documented NSTI! 65 excluded (NSTI unproven on histopathology, no tissue or wound swab)! 154 cohort for analysis! Patients per year 18 (IQR11-20)! 59.1% male mean age 54yrs (sd 17.2yrs)

33 Epidemiology! Predisposing factors! None (44), diabetes (60), surgery/trauma (40), immuno-suppressed (22)! Wound location! 46.8% Perineal abdomen, 34.4% extremity! Inpatient stay 28.6 days ( days)! HBO treatments 8 (6-12)! Surgical debridements 3 ( 2-5)! Time to debridement 17.7 hrs ( hrs)

34 Pathogens! Gram positive aerobes! 24% Strep pyogenes! 26% Staph Aureus! Gram Negative aerobes! 10% Enteric (E Coli, Proteus)! 7% Non Enteric GNB (Pseudomonas, Acintobacter)! Anaerobes! Clostridia, Bacteroides! Fungi! Cryptococcus, Mucor Indicus Gram positive aerobes Gram negative aerobes Anaerobes Fungi Other

35 Mortality! Increased age! 65.9 vs 52.4years, p=0.001! Higher requirement for ICU! 100% vs 69.9%, p=0.007! Higher APACHE-2 scores! APACHE-2 score: 17.9 vs 15.1, p=0.018! Other factors (gender, predisposing factors, wound location, pathogen) did not significantly impact on mortality

36 HBOT 4th Antibiotic?! Studies controversial! Very difficult to do a RCT! Only a few cases per year! The ones that arrived at the hospital are the less critical probably

37 Pro and Con

38 Thank you for your attention