Indwelling Catheter Risks

An indwelling urinary catheter provides continuous bladder drainage, but it also creates a persistent route through the urethra into the bladder. The device bypasses normal defenses and can develop a microbial biofilm that is difficult to eliminate. The longer it remains, the greater the opportunity for bacteria to ascend and multiply. The incidence of bacteriuria rises by approximately 7% for each day the catheter remains in place. Duration is therefore the most important modifiable risk factor, and the risk increases markedly after 7 days of continuous use. Diabetes mellitus, female sex, fecal incontinence, and dehydration add patient-specific risk; they strengthen the reason to avoid an unnecessary catheter but do not make a needed catheter automatically unsafe. The experienced nurse does not begin with the urine's color or odor. The first question is, “Does this patient still need an indwelling catheter?” The benefit of reliable drainage or accurate output measurement must continue to outweigh the risks of infection, urethral trauma, bleeding, bladder spasms, and impaired mobility.