Managing post-kidney transplantation urinary catheters

Urinary fistulae are a frequent complication of urological interventions in the postoperative period with an estimated incidence as high as 8%. It is crucial to preserve periureteral adipose tissue to ensure an adequate blood supply to the ureter, thereby preventing complications such as ischemia and necrosis, which can lead to urinary fistulae. To minimise these risks, double J ureteral catheters should be used during renal transplantation as they provide a protective effect against urinary fistulae. Nevertheless, these catheters may also cause vesicoureteral reflux, increased UTI incidence, and ureteral obstruction, potentially impairing renal graft function.

Urethral catheters are used post-transplant to prevent bladder overdistension, avoid vesicoureteral reflux, and support ureteral anastomosis without resulting in urinary fistulae. [3] However, if not removed in a timely manner, these catheters may cause lower UTIs characterised by annoying symptoms. Therefore, careful monitoring and timely removal of these catheters are essential to balance their benefits and risks.

Current practices and recommendations
Unfortunately, no valid and approved protocols currently exist to determine the duration of urinary catheter use after transplantation. A survey among urologists revealed that 44% removed the bladder catheter within the first week after surgery, while 6% maintained it for at least two weeks. Additionally, 18% of respondents kept the ureteral catheter for 1-2 weeks, and 51% for at least three weeks.

At the recent EAU24 congress in Paris, a session conducted by the ESIU with the collaboration of the EAU Section of Transplantation Urology (ESTU) aimed to reach a consensus on catheter removal timing. Evidence was reviewed, indicating that prolonged catheter use is associated with a higher incidence of UTIs. Key factors for defining early removal include adequate urine output and proper healing of the bladder, as these can be compromised by end-stage renal disease. Some studies have indicated that in patients with adequate urine output, especially after living-donor transplants, urethral catheters can be safely removed within 24 to 48 hours post-surgery.

A recent meta-analysis defined early removal as five days, finding no significant difference in asymptomatic bacteriuria incidence between early and late removal, though high-quality randomised controlled trials are needed.

Ureteral stents and catheter removal timing
A Cochrane review by Thompson et al. focused on ureteral catheters used after kidney transplantation, revealed that the universal use of ureteral stents in kidney transplantation significantly reduces the incidence of major urological complications, such as urinary leakage or fistulas and ureteral stenosis.

The review aimed to evaluate the evidence regarding early stent removal. A significant challenge identified was the lack of a clear definition for early ureteral stent removal. Using a 15-day cutoff, a lower rate of UTIs was observed with early removal. The primary outcome of the review was to assess whether there is a difference in the incidence of major urological complications between early and late removal of ureteral catheters. Additionally, thereview analysed the incidence of UTIs, idiosyncratic stent-related complications, hospital-related costs, and adverse events. The analysis included five studies with a total of 1,127 patients.

The review reported no evidence that early stent removal (defined as less than 15 days) compared to late stent removal is associated with a lower incidence of major urological complications. However, the incidence of UTIs may be reduced in the early stent removal group (five studies, 1,127 participants: RR 0.49, 95% CI 0.30 to 0.81; moderate certainty evidence). The review also evaluated different types of ureteral stents, categorised as percutaneous (PC), per-urethral (PU), or bladder indwelling (BI). The advantage of a reduced incidence of UTIs was only observed with the use of BI.

Survey for developing consensus on optimal catheter removal timing
During the ESIU session, audience members engaged in a live debate, with 70.2% agreeing that early urethral catheter removal is the best strategy to prevent post-transplant UTIs, and 60% supporting early double J catheter removal. Furthermore, 42.6% believed early catheter removal is safe and does not increase the risk of complications like urinary fistulas and ureteral strictures, with this percentage rising 68.1% when patients had adequate diuresis.

Regarding the optimal timing for catheter withdrawal, 51.1% of respondents favoured removing urethral catheters within one week, while 42.6% suggested 1-2 weeks. For double J ureteral catheters, 59.6% recommended 1-2 weeks, and 31.9% preferred more than two weeks. Antimicrobial prophylaxis before catheter removal was deemed unnecessary by 55.3% for urethral catheters and 40.4% for ureteral catheters.

Conclusion
The use of ureteral stents after kidney transplantation can prevent urinary fistulae. However, late removal may increase the incidence of UTIs. It is therefore vital to determine the optimal timing for the early removal of both urethral and ureteral catheters. Based on the currently available evidence, early removal can be considered at five days for urethral catheters and fifteen days for ureteral stents. Several factors may influence the optimal timing for catheter removal, including the mode of donation (live or cadaver), delayed graft function, adequate urinary output, expanded criteria donors, and neurogenic bladder may influence the optimal timing for catheter removal.