Surgical infections

Surgical Infections

1. SURGICAL INFECTIONS

2. SURGICAL INFECTIONS Infections that require surgical treatment or related to operative interventions

3. SURGICAL INFECTIONS Infections required surgical treatment • Necrotizing soft tissue infections • Infections of body cavities (peritonitis, empyema, etc.) • Infections confined to an organ or tissue (abscesses, septic arthritis, cholecystitis, etc) • Prosthetic device infections

4. SURGICAL INFECTIONS INFECTIONS RELATED TO OPERATIVE INTERVENTION • Wound infections - Surgical site infections • Postoperative infections (peritonitis or other cavity infections) • Surgical nosocomial infections (pneumonia, urinary tract infections, catheter infections)

5. NOSOCOMIAL INFECTIONS Occurs after the initial 48 hours of admission • Urinary tract infection • (IV) Catheter-related infection • Lower respiratory tract infection • Infection via transfusion • Bacteriemia and Sepsis

6. PATHOGENESIS DETERMINANTS OF INFECTIONS Microorganism Host Defenses (virulance) (type&severity of immunosupression) INFECTION Environment (Fluids, foreign bodies, a closed unperfused space etc.)

7. Infectious agent The Endogenous Gastrointestinal Microflora • Stomach • Duodenum Aerobes and anaerobes • Proximal small bowel <10 4 /mL • Distal small bowel Enterobacteriaceae Enterococcus spp 10 3 -10 8 /mL Anaerobic organisms • Colon Anaerobic organisms Bacteriodes fragilis 10 12 /mL

8. Microbiology of Intraabdominal Infections Aerobes: Escerichia coli Klebsiella spp. Proteus spp Enterobacter spp Enterococcus spp Anaerobes: Bacteriodes spp Peptostreptococcus spp Clostridium spp Bilophila wadsworthia Fungi,Candida

9. HOST DEFENSE MECHANISMS Nonspecific Surface Mechanical barrier (skin, mucosa) Secretory barrier Immunoglobulins Ciliary motion Movement

10. HOST DEFENSE MECHANISMS Specific Cellular defense Phagocytic cells Cell-mediated immunity (PNLs, eosinophils, mononuclear cells) (T lymphocytes & macrophages) Natural killer cells Humoral defense Lyzozyme Immunoglobulins Complement Interferon

11. A Susceptible host Causes of Impaired Host Resistance to Infection Patient ’ s Underlying Condition • AIDS • Remote infection • Neoplasia • Malnutrition • Acute stress (burns, trauma) • Metabolic illness (DM, uremia) • Aging • Obesity • Smoking

12. A Susceptible host Iatrogenic • Antineoplastic chemotherapy • Immunosuppressive therapy (allograft recipients, autoimmune disorders) • Splenectomy

13. Infection Environment Wound or a natural space with narrow outlets Fluids, foreign bodies, a closed unperfused space etc

14. Clinical finding LOCAL MANIFESTATIONS OF SURGICAL INFECTIONS • CELLULITIS: Spreading infection of the skin and subcutaneous tissue • LYMPHANGITIS: Inflammation of the lymphatic channels in the subcutaneous tissue • ABSCESS: Localized accumulation of purulent material situated in the dermis or subcutaneous tissue

15. SURGICAL SITE INFECTION The term “ surgical site infection ” now replaces “ surgical wound infection ” • Superficial incisional SSI; involves the skin or subcutaneous tissue • Deep incisional SSI; involves the deep tissue such as fascia or muscle,Organ/space SSI

16. SURGICAL SITE INFECTION DEFINITION Superficial Incisional Infection Any incisional infection occuring within postoperative 30 days at any level above fascia described as; • Presence of any purulant discharge (culture may not reveal any opponent) • Any positive culture findings from primarily closed incision • Deleberate incision exploration • Infection diagnosis determined by the surgeon

17. SURGICAL SITE INFECTION DEFINITION Deep Incisional /Organ / Space Infection Any infection occuring within postoperative 30 days or within postoperative one year if any implant is left described as; • Presence of any purulant discharge (through drains) • Any positive culture findings from intraabdominal samples • Spontaneous wound dehiscence • Presence of abscess • Infection diagnosis determined by the surgeon

18. Diagnosis • Redness • Swelling • Hyperthermia • Fluctuation • Purulent or turbid aspirate

19. OPERATIVE WOUNDS NATIONAL RESEARCH COUNCIL CLASSIFICATION OF OPERATIVE WOUNDS

20. CLASSIFICATION OF OPERATIVE WOUNDS CLEAN • Nontraumatic • No inflammation encountered • No break in technique • Respiratory, alimentary, genitourinary tracts not entered

21. CLASSIFICATION OF OPERATIVE WOUNDS CLEAN CONTAMINATED • Gastrointestinal or respiratory tracts entered without significant spillage • Appendectomy • Oropharynx entered • Vagina entered • Genitourinary tract entered in absence of infected urine • Biliary tract entered in absence of infected bile • Minor break in technique

22. CLASSIFICATION OF OPERATIVE WOUNDS CONTAMINATED • Major break in technique • Gross spillage from gastrointestinal tract • Traumatic wound, fresh • Entrance of genitourinary or biliary tracts in presence of infected urine or bile

23. CLASSIFICATION OF OPERATIVE WOUNDS DIRTY and INFECTED • Acute bacterial inflammation encountered, without pus • Transection of clean tissue for the purpose of surgical access to a collection of pus • Traumatic wound with retained devitalized tissue,foreign bodies, fecal contamination, and/or delayed treatment, or from dirty source.

24. Treatment Principles of Antibiotic Therapy • Why to use antibiotics? • Where is infection? • What are the most probable pathogens? • How about antibiotic susceptibility? • Pharmacological properties • Is combination of antibiotics necessary? • Host factors • Monitoring accuracy of therapy