Skip to content

Reducing the Risk of Infection in Elective and Emergent Colectomy Patients

Introduction

  • Colorectal surgery has a higher risk of infections compared to other surgical specialties.
  • Patients are susceptible to:
    • Surgical site infections (SSIs)
    • Respiratory infections
    • Urinary tract infections (UTIs)
    • Line-related infections
    • Clostridium difficile infections
  • Perioperative measures can reduce these complications and improve outcomes.

Surgical Site Infection (SSI)

Overview

  • Incidence: SSI rates range from 5% to 30% in colorectal surgery.
  • Definition: Infection at or near the surgical incision within 30 days (or within a year if prosthetic material is implanted).
  • Classification:
    • Superficial Incisional SSI: Affects skin or subcutaneous tissue.
    • Deep Incisional SSI: Involves muscle and fascia.
    • Organ/Space SSI: Affects any anatomical part opened or manipulated during surgery.

image.png

image.png

Impact

  • Morbidity and Mortality: SSIs are the most frequent adverse events post-surgery.
  • Healthcare Costs:
    • Prolonged hospitalization
    • Readmissions
    • Reoperations
    • Extended hospital stay: Average of 9.7 days longer.
    • Increased costs: Additional $20,842 per admission.

Prevention

  • Requires a multidisciplinary approach:
    • Involvement of nurses, surgical staff, and physicians.
    • Measures at every care step: preoperative, intraoperative, and postoperative.
    • Audit and surveillance of SSI rates.
    • Providing feedback and education to healthcare personnel.

Pathogenesis and Microbiology of SSIs in Colorectal Surgery

Sources of Infection

  • Endogenous Flora:
    • Major source (>80%) of SSIs.
    • Colonic lumen contains:
      • Up to 10¹² bacteria per gram of content.
      • Over 600 different species.
    • Common organisms:
      • Escherichia coli (E. coli): Gram-negative aerobic bacteria.
      • Bacteroides fragilis (B. fragilis): Gram-negative anaerobic bacteria.
    • Synergistic relationship: E. coli and B. fragilis enhance each other's virulence.
  • Exogenous Sources:
    • Skin colonization: Less than 20% of SSIs.
    • Operating room environment: Infected instruments or materials.
    • Staphylococcus aureus (including MRSA) from surgical team members.

Host Factors

  • Impaired Immune Response:
    • Immunodeficiency
    • Chronic conditions: diabetes, liver/kidney/lung diseases, cancer.
  • Effect: Increased susceptibility to SSIs.

Environmental and Technical Factors

  • Contributing Factors:
    • Hematomas or necrotic tissue at the surgical site.
    • Presence of foreign bodies.
    • Dead space in tissues.
  • Stool Spillage:
    • Leads to peritoneal contamination.
    • Risk of abscess formation in dependent areas like the pelvis.

Anastomotic Leaks

  • Incidence: 2% to 20% after colorectal surgery.
  • Risk Factors:
    • Patient age and sex
    • Obesity
    • Comorbidities
    • Radiation and chemotherapy
    • Surgical technique and experience

Preoperative Measures for Prevention of SSIs

Malnutrition

  • Prevalence: 30% to 50% of patients.
  • Impact:
    • Hypoalbuminemia (<3.5 g/dL) increases postoperative morbidity.
    • Malnutrition may impair wound healing.
  • Recommendation:
    • Conduct nutritional assessment.
    • Provide nutritional support preoperatively.

Active Infection

  • Classification: Wounds with active infection are considered dirty.
  • SSI Risk: Up to 40% in dirty wounds.
  • Recommendation:
    • Allow healing of active infections before elective surgery.

Smoking Cessation and Nicotine Replacement Therapy

  • Effects of Smoking:
    • Constricts peripheral blood vessels.
    • Leads to tissue hypovolemia and hypoxia.
    • Interferes with wound healing.
  • Evidence:
    • 4 weeks of smoking cessation reduces SSIs.
  • Recommendation:
    • Encourage smoking cessation preoperatively.
    • Nicotine replacement therapy may be used.

Prolonged Preoperative Hospitalization

  • Impact:
    • Increases SSI rates due to colonization with resistant flora.
  • Recommendation:
    • Minimize preoperative hospital stay when possible.

Preoperative Cleansing of the Surgical Site

  • Evidence:
    • No significant reduction in SSIs with antiseptic bathing.
  • Recommendation:
    • Standard preoperative cleansing is acceptable.

Bowel Preparation

  • Historical Context:
    • Mechanical bowel preparation (MBP) alone is insufficient.
    • Combined with oral antibiotics, it reduces colonic bacteria.
  • Current Practice:
    • MBP with oral antibiotics significantly reduces SSIs.
    • Timing: Oral antibiotics should be administered after completing MBP.
  • Recommendation:
    • Use MBP combined with oral antibiotics for elective colon resections.
    • Example regimen: Polyethylene glycol solution with oral neomycin and metronidazole.

Intraoperative Measures for Prevention of SSIs

Prophylactic Antibiotics

  • Importance:
    • Most significant method to reduce SSIs.
  • Timing:
    • Administer within 60 minutes before incision.
    • Within 120 minutes for vancomycin or fluoroquinolones.
  • Selection:
    • Target likely pathogens:
      • Aerobic and anaerobic bacteria.
    • Preferred agents:
      • First-generation cephalosporins with metronidazole.
      • Alternative: Clindamycin with a fluoroquinolone.
  • Dosage Considerations:
    • Adjust doses for patients with BMI >30 kg/m².

Hair Removal

  • Impact:
    • Shaving increases SSI rates.
  • Recommendation:
    • Avoid hair removal unless necessary.
    • If required, use clippers, not razors.

Skin Antisepsis

  • Agents Used:
    • Chlorhexidine
    • Povidone-iodine
    • Isopropyl alcohol
  • Evidence:
    • Chlorhexidine is more effective than povidone-iodine.
    • Chlorhexidine-alcohol combinations are superior.
  • Recommendation:
    • Use chlorhexidine-based antiseptics for skin preparation.

Surgical Hand Hygiene, Technique, and Minimally Invasive Surgery

  • Hand Hygiene:
    • No clear evidence favoring one method over another.
  • Surgical Technique:
    • Minimize tissue injury.
    • Ensure proper hemostasis.
  • Minimally Invasive Surgery:
    • Associated with reduced SSI rates.
  • Recommendation:
    • Opt for minimally invasive approaches when feasible.

Wound Protectors and Wound Irrigation

  • Wound Protectors:
    • May reduce SSIs by preventing contamination.
    • Evidence is mixed.
  • Wound Irrigation:
    • Intraoperative irrigation may reduce SSIs.
    • Antibiotic solutions show stronger effects.
  • Recommendation:
    • Consider using wound protectors and irrigation in high-risk patients.

Increased Oxygen Delivery

  • Evidence:
    • High inspired oxygen concentrations may reduce SSIs.
  • Recommendation:
    • Administer 80% inspired oxygen during surgery and for 2 hours afterward.

Preservation of Normothermia

  • Impact:
    • Hypothermia may impair wound healing.
  • Evidence:
    • Maintaining normothermia reduces SSIs.
  • Recommendation:
    • Keep core temperature around 36.7°C during surgery.

Postoperative Measures for Prevention of SSIs

Glycemic Control

  • Impact:
    • Hyperglycemia causes immunosuppression.
  • Evidence:
    • Elevated glucose levels increase SSI risk.
  • Recommendation:
    • Monitor and maintain optimal blood glucose levels postoperatively.

Dressings and Wound Care

  • Dressings:
    • May be removed 24 hours after surgery for closed wounds.
  • Wound Management:
    • Probing and wicks may help in contaminated wounds.
  • Advanced Therapies:
    • Negative pressure wound therapy is under investigation.

Reducing the Risk of Other Infections

Urinary Tract Infections (UTIs)

  • Incidence: Occur in over 4% of patients.
  • Risk Factors:
    • Female sex
    • Open procedures
    • Rectal surgeries
    • Age over 65
    • Nonindependent functional status
    • Steroid use
    • Longer operative time
  • Impact:
    • Longer hospital stays
    • Higher reoperation rates
    • Increased 30-day mortality
  • Prevention:
    • Early catheter removal (postoperative day 1 or immediate recovery).
    • Sterile catheter placement intraoperatively.
    • For rectal surgeries, remove catheter on day 3 to 6 due to retention risk.

Respiratory Tract Infections

  • Incidence: Approximately 6% post-surgery.
  • Impact:
    • Major cause of perioperative death.
  • Prevention:
    • Smoking cessation prior to surgery.
    • Early mobilization postoperatively.
    • Pulmonary care:
      • Use of incentive spirometry.
      • Coughing and deep breathing exercises.
      • Oral hygiene.
      • Head-of-bed elevation.

Clostridium difficile Infection

  • Etiology:
    • C. difficile is an anaerobic, spore-forming bacterium producing toxins A and B.
  • Risk Factors:
    • Antibiotic use
    • Proton pump inhibitors
    • Older age
    • Immunosuppression
    • Hospitalization
  • Symptoms:
    • Crampy abdominal pain
    • Diarrhea
  • Diagnosis:
    • PCR testing for toxins
    • Stool culture
  • Treatment:
    • Mild cases: Oral metronidazole.
    • Severe cases: Oral vancomycin.
    • Recurrent or severe disease: Fidaxomicin may be superior.
    • Fulminant colitis: May require total abdominal colectomy.

Conclusion

  • Prevention of SSIs involves:
    • Optimized preoperative preparation.
    • Perioperative bowel preparation with MBP and oral antibiotics.
    • Adherence to antibiotic prophylaxis guidelines.
    • Proper tissue handling during surgery.
    • Increased intraoperative oxygen delivery.
    • Wound irrigation and protection.
    • Maintenance of normothermia.
    • Postoperative glycemic control.
  • Prevention of UTIs:
    • Early urinary catheter removal.
    • Sterile catheter techniques.
  • Prevention of Respiratory Infections:
    • Smoking cessation.
    • Early mobilization.
    • Pulmonary care protocols.
  • Future Directions:
    • Ongoing research into SSI biology.
    • Development of novel preventive measures.