Does Antibiotic Prophylaxis Prevent Postoperative UTIs in Patients Requiring Short-term Catheterization?

Abstract & Commentary

By Chiara Ghetti, MD

Associate Professor, Obstetrics and Gynecology, Division
of Female Pelvic Medicine and Reconstructive Surgery, Washington University School of Medicine, St. Louis, MO

Dr. Ghetti reports no financial relationships relevant to this field of study.

Synopsis: After pelvic floor reconstructive surgery, antibiotic prophylaxis with daily nitrofurantoin during postoperative catheterization does not decrease risk of urinary tract infection.

Source: Dieter AA, et al. Oral antibiotics to prevent postoperative urinary tract infection: A randomized controlled trial. Obstet Gynecol 2014;123:96-103.

Catheter-related urinary tract infections (uti) are the most frequent hospital-acquired infections. The estimated risk of UTI following pelvic reconstructive surgery is 5-35%.¹ This study attempted to answer the question of whether antibiotics effectively decrease the risk of UTI in patients requiring catheter drainage following reconstructive surgery.

This was a randomized, double-blind, placebo-controlled trial of patients undergoing surgery for pelvic organ prolapse and/or incontinence requiring postoperative catheterization. The primary outcome was defined as treatment for UTI within 3 weeks of surgery. English-speaking, non-pregnant patients age ≥ 21 years having surgery for pelvic floor disorders were enrolled. Patients undergoing surgery for urethral diverticulum, fistula repair, or sacral modulation or who had an intraoperative urinary tract injury were excluded. Women with an allergy to nitrofuratoin, creatinine clearance < 60 mL/min, or preoperative urinary retention requiring catheterization also were excluded. Subjects requiring postoperative catheterization were randomized to receive daily nitrofurantoin prophlyaxis vs placebo for 7 days starting on postoperative day 1. These included all subjects hospitalized postoperatively with Foley catheter drainage as well as all subjects discharged on day of surgery with Foley catheter or performing clean intermittent self-catheterization. All subjects received guideline-recommended perioperative antibiotic prophylaxis prior to the start of surgery. Treatment for UTI was defined as treatment for either clinically suspected or culture-proven infection. Multiple methods (including query of medical record, postoperative visits, and completion of forms by outside facilities) were used to determine whether UTI treatment had occurred in the 3 weeks following surgery. Sample size calculation estimated that 156 participants were necessary to demonstrate a two-thirds reduction in risk of UTI.

The study enrolled 375 subjects, of which 163 were randomized. Four randomized subjects were excluded from final analysis for protocol deviations. Final analysis included 159 subjects, 81 in the nitrofurantion treatment group and 78 in the placebo group. Baseline and perioperative characteristics were not different between groups. Groups were also not different in duration or type of catheter use after surgery.

The risk of UTI in the 3 weeks following surgery was 18% in all subjects (28/159). The risk was not different between nitrofurantion (22%) vs placebo groups (13%) (relative risk 1.73; 95% confidence interval [CI], 0.85-3.52; P = 0.12). Of those treated, 68% were treated for a culture-proven UTI and 32% were treated empirically for a clinically suspected UTI. Using regression analysis, there was no difference in risk of UTI when controlling for menopausal status, diabetes, preoperative post-void residual, creatinine clearance, hysterectomy, and duration of catheterization. The authors conclude that nitrofurantoin prophylaxis for each day of catheterization does not reduce UTI risk in patients undergoing reconstructive pelvic surgery requiring short-term transurethral catheterization.

Commentary

UTIs account for 40% of hospital-acquired infections and the majority (80%) of these are associated with the use of indwelling catheters.² Catheter-associated urinary tract infections (CAUTI ) can be associated with increased morbidity and mortality, increased hospitalization, as well as increased health care costs. CAUTI have received increased attention in recent years with the publication of numerous guideline documents and adoption of quality measures. In 2009, as part of National Hospital Inpatient Quality Measures, removal of catheter on postoperative day 1 or 2 was added as a Surgical Care Improvement Project (SCIP) measure to improve surgical care by reducing surgical complications. In 2012, the Joint Commission published a new National Patient Safety Goal specific to CAUTI based on the Compendium of Strategies to Prevent Healthcare-Associated Infections in Acute Care Hospitals and the CDC Guideline for Prevention of Catheter-associated Urinary Tract Infections.^3,4 In January 2013, there was full implementation of CAUTI surveillance of evidence-based practices to prevent indwelling CAUTI.

The main tenets employed to reduce CAUTI are to avoid unnecessary catheterization and to limit duration of catheterization.⁵ Due to antibiotic side effects and risk of antimicrobial resistance, the role of prophylactic antibiotics has been debated. The 2013 Cochrane review concluded that there is limited evidence suggesting that receiving prophylactic antibiotics reduces the rate of bacteriuria and other signs of infection in surgical patients who undergo bladder drainage for at least 24 hours postoperatively. This randomized, double-blind, placebo-controlled study found that nitrofurantoin prophylaxis during time of catheterization following reconstructive surgery did not reduce the risk of UTI. While this well-designed study adds important information regarding this clinical dilemma, what remains unanswered is whether antibiotic prophylaxis with another agent or whether prophylaxis that extends beyond the period of catheterization would reduce UTI risk in this population.

References

1. Dieter AA, et al. Obstet Gynecol 2014;123:96-103.
2. Lusardi G, et al. Cochrane Database Syst Rev 2013;7:CD005428.
3. Society for Healthcare Epidemiology of America. Infection Control Hosp Epidemiol 2008;29(Suppl 1):51-92. Available at: www.shea-online.org/about/compendium.cfm, Accessed Feb. 28, 2014.
4. Healthcare Infection Control Practices Advisory Committee (HICPAC): Guideline for Prevention of Catheter-Associated Urinary Tract Infections 2009. Atlanta, GA: Centers for Disease Control & Prevention, 2009. Available at: www.cdc.gov/hicpac/cauti/001_cauti.html. Accessed Feb. 28, 2014.
5. Pratt RJ, et al. J Hosp Infect 2007;65(Suppl 1):S1-64.