Complications of Foley catheters--is infection the greatest risk?

Foley catheters cause a variety of harms, including infection, pain and trauma. Although symptomatic urinary tract infection and asymptomatic bacteriuria are frequently discussed, genitourinary trauma receives comparatively little attention.

A dedicated Foley catheter nurse prospectively reviewed the medical records of inpatients with a Foley catheter at the Minneapolis Veterans Affairs Medical Center from August 21, 2008 to December 31, 2009. Daily surveillance included Foley catheter related bacteriuria and trauma. Data were analyzed as the number of event days per 100 Foley catheter days.

During 6,513 surveyed Foley catheter days, urinalysis/urine culture was done on 407 (6.3%) days. This testing identified 116 possible urinary tract infection episodes (1.8% of Foley catheter days), of which only 21 (18%) involved clinical manifestations. However, the remaining 95 asymptomatic bacteriuria episodes accounted for 39 (70%) of 56 antimicrobial treated possible urinary tract infection episodes (for proportion of treated episodes with vs without symptomatic urinary tract infection manifestations, p = 0.005). Concurrently 100 instances of catheter associated genitourinary trauma (1.5% of Foley catheter days) were recorded, of which 32 (32%) led to interventions such as prolonged catheterization or cystoscopy. Trauma prompting an intervention accounted for as great a proportion of Foley catheter days (0.5%) as did symptomatic urinary tract infection (0.3%) (p = 0.17).

In this prospective surveillance project, intervention triggering Foley catheter related genitourinary trauma was as common as symptomatic urinary tract infection. Moreover, despite recent increased attention to the distinction between asymptomatic bacteriuria and symptomatic urinary tract infection in catheterized patients, asymptomatic bacteriuria accounted for significantly more antimicrobial treatment than did symptomatic urinary tract infection. Elimination of unnecessary Foley catheter use could prevent symptomatic urinary tract infection, unnecessary antimicrobial therapy for asymptomatic bacteriuria and Foley catheter related trauma.