What has a greater risk of infection, a Foley catheter or repeated straight catheterization (straight cath)?

Infection Risk Comparison: Foley Catheter vs. Repeated Straight Catheterization

Repeated straight catheterization carries a lower risk of urinary tract infection compared to indwelling Foley catheters. 1, 2

Infection Risk Comparison

• Indwelling Foley catheters are colonized by microorganisms within 24 hours after insertion, leading to biofilm formation on both external and internal surfaces that protects bacteria from antimicrobials and host immune responses 1, 3
• For patients with indwelling catheters, the infection rate is approximately 5% per day, making duration of catheterization the principal determinant of infection risk 3
• Indwelling catheters are associated with a 2.178 times higher odds ratio for urinary tract infections compared to no catheterization in total hip arthroplasty patients 4
• Indwelling catheters significantly increase the risk of periprosthetic joint infection following total knee arthroplasty (odds ratio 2.647, p<0.001), while intermittent catheterization does not significantly increase this risk 5

Mechanism of Infection

• Biofilm formation on catheter surfaces is the primary mechanism for catheter-associated infections 1
• Biofilms consist of:
  • Host factors (fibrinogen, fibrin, fibronectin, extracellular polysaccharides) 1
  • Microbial products (glycocalyx or "slime") 1
• These biofilms provide:
  • Protection for bacteria against antimicrobials 3
  • Resistance against host immune responses 3
  • Adhesion sites for organism binding, particularly Staphylococcus aureus 1

Evidence Supporting Intermittent Catheterization

• Recent systematic reviews show that most studies fail to demonstrate a significant difference in UTI risk between catheter types, but when differences exist, they favor intermittent catheterization 2
• In orthopedic surgery patients, indwelling catheterization was associated with significantly higher risk of periprosthetic joint infection, while intermittent catheterization showed no significant increase in risk 5
• The Infectious Diseases Society of America recommends changing catheters based on clinical indications rather than on a fixed schedule for patients requiring long-term catheterization 6

Clinical Implications and Recommendations

• For patients requiring bladder management, intermittent catheterization should be the preferred method when feasible 5, 4
• If an indwelling catheter is necessary, it should be removed as early as possible when no longer needed 6
• Daily evaluation of the continued need for catheterization is recommended to minimize infection risk 6
• Avoid catheter blockage, twisting, or trauma, which can increase infection risk 3
• Do not administer antimicrobials for asymptomatic catheter-acquired UTI, as this does not decrease symptomatic episodes but leads to emergence of resistant organisms 3

Special Considerations

• Patients with specific conditions (receiving chemotherapy, total parenteral nutrition, or prolonged neutropenia) are at increased risk for catheter-related infections 7
• For patients who experience repeated early catheter blockage from encrustation, some experts suggest changing catheters every 7-10 days, though this intervention has not been evaluated in clinical trials 6
• The average cost per episode of catheter-related bloodstream infection is approximately $45,814, making prevention strategies highly cost-effective 7

Remember that while the evidence generally favors intermittent catheterization over indwelling catheters for infection prevention, the decision should consider the specific clinical scenario, patient factors, and available resources.