Understanding Surgical Infections: Prevention, Diagnosis, and Treatment Strategies

1. Surgical Infections MS-3 Surgery Clerkship Lecture Eric Simms, M.D.

2. Ignaz Semmelweis 1847 Realized that washing hand with a chlorinated lime solution decreased incidence of newborn death from “puerperal fever’.

3. Joseph Lister • 1883-1897 • British surgeon • Used Carbolic Acid (Phenol) to clean hands, instruments and wipe on surgical wounds drastically decreased infections.

4. Overview • Recognizing Infection • Soft Tissue Infections • Post-operative Infections • Surgical Site Infection • Hospital Acquired Infections • Antibiotic Prophylaxis • Blood Born Pathogens

5. Infection Infection is defined by: • Microorganisms in host tissue or the bloodstream • Inflammatory response to their presence.

7. Inflammatory Response Localized: • Rubor, Calor, Dolor, Tumor, and functio laesa (loss of function) Systemic: • Systemic Inflammatory Response Syndrome (SIRS)

8. S.I.R.S. Any Two of the Following Criteria • Temperature: < 36.0, >38.0 • Heart Rate : >90 • Respiratory Rate: >20 • WBC: <4,000, >12,000

9. Sepsis Definition: SIRS plus evidence of local or systemic infection. Septic Shock Definition: Sepsis plus end organ hypoprofusion. Mortality of up to 40%

10. Soft Tissue Infections: • Cellulitis • Abscess • Necrotizing Infections

11. Cellulitis

12. Cellulitis Definition: Diffuse infection with severe inflammation of dermal and subcutaneous layers of the skin Diagnosis: Pain, Warmth, Hyperesthesia Treatment: Antibiotics. Common Pathogens: Skin Flora (Streptococcus/Staphylococcus)

13. Abscess

14. Abscess Definition: Infectious accumulation of purulent material (Neutrophils) in a closed cavity Diagnosis: Fluctuant: Moveable and compressible Treatment: Drainage

15. Necrotizing Soft Tissue Infection

16. Necrotizing Soft Tissue Infection Definition: Deep infection of skin and soft tissue that may spread rapidly along facial planes. Diagnosis: Purely Clinical, dishwater discharge, gray tissue, pain out of proportion to examination, bulla, and dark, golden discoloration. Treatment: True Surgical Emergency, Antibiotics

17. Necrotizing Soft Tissue Infection • Common Pathogens • Clostridium • Group A streptococcus • Polymicrobial • Toxic Shock Syndrome • Streptococcus • Staphylococcus

18. Post-Operative Infections • Fever After Surgery • The “Five W’s” • Wind: Atelectisis • Water: UTI • Walking: DVT • Wonder Drug: Medication Induced • Wound: Surgical Site Infection

19. Surgical Site Infections • 3rd most common hospital infection • Incisional • Superficial • Deep • Organ Space • Generalized (peritonitis) • Abscess

21. Types of Surgery

22. Host Risk Factors • Diabetes mellitus • Hypoxemia • Hypothermia • Leukopenia • Nicotine (tobacco smoking) • Immunosuppression • Malnutrition • Poor skin hygiene

23. Perioperative Risk Factors • Operative site shaving • Breaks in operative sterile technique • Improper antimicrobial prophylaxis • Prolonged hypotension • Contaminated operating room • Poor wound care postoperatively • Hyperglycemia • Wound closure technique

24. Treatment • Incisional: open surgical wound, antibiotics for cellulitis or sepsis • Deep/Organ space: Source control, antibiotics for sepsis

25. Operative Antibiotic Prophylaxis • Decreases bacterial counts at surgical site • Given within 30 minutes prior to starting surgery • Vancomycin 1-2 hours prior to surgery • Redose for longer surgery • Do not continue beyond 24 hours

27. Other Hospital Acquired Infections • Urinary Tract Infection • Indwelling Catheter Infection • Pneumonia

28. Use/Choice of Antibiotics • Use only when indicated • Start with broad spectrum antibiotics designed to cover likely pathogens • Take cultures when possible • Deescalate spectrum once pathogen is know • Have a plan for duration

29. Occupational Blood Bourne Virus Infections