Preventing Surgical Site Infections for Gastrointestinal Surgery Dr CHIA Chi Fung (Queen Elizabeth Hospital) Joint Hospital Surgical Grand Round Jan 2017

Wound matters M/70, Newly found Ca rectum Hx of lap R hemicolectomy for Ca caecum APR + Total colectomy + End-ileostomy done Post-op discharge from laparotomy wound on D7 Wound C/ST: Proteus, E Coli, Pseudomonas Prolonged hospital stay for wound care till D23

Wound matters F/83, Strangulated incisional hernia Hx of LAR for Ca rectum Small bowel resection and defect repair done Gapping with purulent discharge on D6 Wound swab: Klebsiella, Enterococcus CT: Inflammatory change at wound Subcutaneous collection at abdominal wall Given TPN, daily dressings Meropenem, vancomycin

Surgical Site Infections (SSI) Procedure-related infection at or near incision Within 30 days (or within 90 days if prosthetic material) Translates to morbidity, hospital stay, cost and mortality Microbiology: Skin flora Endogenous flora of involved viscus / mucosa

Risk Factors Age Underlying Illness Obesity Smoking Wound Classification Clean: up to 3% Clean-contaminated: up to 8% Contaminated: up to 15% Dirty: up to 40%

How to prevent SSIs? Pre-op preparation Peri-op care Nutrition, S aureus decontamination, Bathing Bowel Preparation Peri-op care Oxygenation, Perfusion Sterile environment, Hand decontamination Skin preparation Antibiotics on induction and impregnated sutures Wound protectors Wound irrigation

Bowel Preparation Polyethylene glycol, Sodium phosphate Good or bad?  Intraluminal faecal mass   Bacterial load ?? Liquefies faeces   Intra-op spillage

Bowel Preparation Yes or No? NICE 2008: ✗ IDSA 2014: ? to combine with oral antibiotics WHO 2016: ✓ with oral antibiotics If only bowel prep, worse than none Meta-analysis 13 RCTs: OR 1.31 (95%CI 1.00-1.72) Benefits other than SSI not taken into account

Oral Antibiotics with bowel prep Better than bowel prep alone Meta-analysis 11 RCTs: OR 0.56 (95%CI 0.37-0.83) What type? What dose? No conclusive evidence High intraluminal concentrations, poor absorption Against facultative Gram-ve & anaerobic bacteria E.g. Neomycin + Metronidazole ? Oral antibiotics alone ? Side effect profile

Surgical Site Preparation What to use? NICE 2013: Iodine or Chlorhexidine IDSA 2014: Alcohol-containing WHO 2016: Alcohol-based chlorhexidine Limitation Small effect size ~ 4 fewer in 100 ? Cost-effective

Wound Protector Minimize wound-edge contamination Yes or No? NICE 2013: ✓ abdominal IDSA 2014: ✓ GI & biliary WHO 2016: ✓ abdominal Lower risk of SSI ~ 10 fewer in 100 Very low quality evidence May not be cost-effective

Wound Irrigation Physical removal + Dilution + Local antibacterial effect How? Syringe pressure? Pulsed irrigation? What? Saline? Povidine-iodine? Antibiotics?

Wound Irrigation Yes or No? NICE 2008: ✗ IDSA 2014: ✓ povidine-iodine WHO 2016: ✓ povidine-iodine Remains debate Mainly based on old evidence or evidence from non-GI surgeries ? Wound irritation

What’s the trend? Oral antibiotics goes with bowel prep Alcohol-based chlorhexidine for skin prep Consider use of wound protectors Wound irrigation with povidone-iodine

To know more Thanks