Long-term catheterisation and its problems

Complications from long-term catheterisation and attendant problems were examined in the plenary session which focused on ageing and the lower urinary tract during the recently concluded 31st Annual EAU Congress held over the weekend in Munich, Germany.

Prof. Florian Wagenlehner (DE) spoke on long-term catheterisation and he underscored the problem of hospital-related urology infections which have risen in recent years. Around 15% to 25% of hospitalized patients had long-term catheters, and 5% to 10% of nursing home residents also received long-term catheters.

“These are often placed for inappropriate indications and physicians are frequently unaware that catheters were used. In a recent survey of US hospitals it was shown that around 50% of doctors did not monitor which patients were catheterised and around 75% of them also did not monitor the duration and/or discontinuation.

He said there are complications that are already known such as catheter-associated urinary tract infections (UTIs), catheter blockade and inflammation of organs. Many other complications include intravesical knotting (rare), catheter fracture and malignancy, fistulae, erosion, abscess, urosepsis, hematuria, urethral stenosis and stricture, severe mechanical trauma, calculi, encrustation and asymptomatic bacterial stenosis, among many others.

Five of the most frequent complications are directly related to catheter use. “With regards mortality, we see that urosepsis and urinary tract infections are the only ones that lead to mortality. However, catheter-associated uropseis has a 60% mortality, a rather high mortality,” according to Wagenlehner.

Regarding the pathogenesis of catheter-associated UTIs (CAUTI), there are two ways of pathogens to gain access into the urinary tract, namely extra and intra-luminal, with the latter caused by a break in the close drainage system. Wagenlehner said the micro-organisms maybe endogenous (meatal, rectal, vaginal), or exogenous which means that pathogens are introduced by other sources, for instance, by the contaminated hands of healthcare personnel during catheter insertion or manipulation.

Wagenlehner said his group has studied over a year the incidence of endogenous versus exogenous related CAUTI, and in 35% of patients with CAUTI this was due to the patient’s own flora, 40% due to foreign flora and in 25% the origin was not known. Once the pathogens have gained access to the urinary bladder, it is only a matter of two to three days until a significant bacteriuria ensues, he said.

Biofilm infections

CAUTI are always biofilm infections and bacteria growing in these biofilms are resistant to antimicrobials and host defences. “There are other evidence-based clinical risk factors for symptomatic UTIs and prolonged catheterization is one main modifiable risk factor,” added Wagenlehner.

There are also other alternative materials available such as silicon-based and silver alloy catheters, but the evidence is not strong whether these materials can really help reduce infections such as bacteriuria and symptomatic UTI.

“What recommendations are we left with? Placed catheters only when indicated, and don’t use them for managing urinary incontinence. Institutions should also develop a list of appropriate indications for inserting catheters,” said Wagenlehner. He added the use of portable bladders scanners to assess residual urine can also be beneficial.

“Catheters should be removed as soon as they are no longer required and institutions should consider nurse-based or electronic physician reminder systems to reduce inappropriate urinary catheterisation,” he noted. Strategies that are not recommended include complex urinary drainage systems, changing the catheters at routine intervals, routine antimicrobial prophylaxis and irrigation of bladder with antimicrobials, to name a few.

For patients that need bladder drainage, there are options such as supra-pubic and urethral catheters, but recent studies showed there is no difference between these catheters in terms of complications.

“Upper urinary tract complications are not adequately addressed. We have to reduce catheter duration,” said Wagenlehner in his concluding remarks.