Surgical site infection in surgery for benign prostatic hyperplasia: comparison of two skin antiseptics and risk factors.

Background: Surgical site infection (SSI) is the second most common type of nosocomial infections in the United States. In Uruguay, the incidence after prostatectomies is 2.6%. The aim of our study was to compare the efficacy of two skin antiseptics and to determine possible risk factors for SSI in patients undergoing surgery for benign prostatic hyperplasia (BPH).

Methods: A randomized trial included 70 patients operated on for BPH, of whom 56 (80%) underwent open surgery. Patients were treated by the same surgical team in a tertiary general hospital that is a referral center for patients with urologic diseases. Skin antisepsis was performed randomly using either 0.5% povidone-iodine or chlorhexidine in an alcohol base (Chemisol(®)). Possible risk factors investigated were age, renal dysfunction, bladder stones, preoperative urinary catheter, positive preoperative urine culture, operative time and technique, and vesicocutaneous fistula.

Results: Of all patients, 41 (59%) had a urinary catheter preoperatively. Urine cultures were positive in 31 patients, of whom 29 (94%) had a urinary catheter. Surgical site infection occurred in 10 patients (18%), and 100% of the causative microorganisms were gram-negative bacteria characteristic of the urinary flora. The type of antiseptic did not affect the risk of SSI (p=1.00). The most important risk factor for infection was the presence of a urinary catheter preoperatively (p=0.003); also significant were the formation of a vesicocutaneous fistula (p=0.008), increasing age (p=0.02), and the presence of a positive preoperative urine culture (p=0.03).

Conclusions: In a cohort of patients submitted to open prostatectomy, SSI was not related to the type of antiseptic. The main risk factor was the presence of a urinary catheter preoperatively. All microorganisms isolated from the SSIs were characteristic of urinary tract infections.