Kink, flow and retention properties of urinary catheters part 1: conventional foley catheters

The safety and feasibility of no-placement of urinary catheter after single-port laparoscopic surgery in patients with benign ovarian tumor: A retrospective cohort study

OBJECTIVE

The aim of this study was to investigate the feasibility and safety of no placement of urinary catheter after single-port laparoscopic surgery in patients with benign ovarian tumor.

MATERIALS AND METHODS

Patients with benign ovarian tumor who received ovarian cystectomy or oophorectomy via single-port laparoscopic surgery in our department were screened between July 2019 and March 2021. Patients were divided into placement of urinary catheter group or no-placement of urinary catheter group according to whether an indwelling catheter was used after single-port laparoscopic surgery, and length of hospital stay, occurrence of postoperative urinary retention, incidence of urinary tract infection and re-insertion rate of urinary catheters were compared.

RESULTS

There was no significant difference in the rate of urinary catheter re-insertion between the two groups (P = 0.431), but a higher incidence of urinary catheter re-insertion was found in the group of dwelling urinary catheter placement. Simultaneously, there were no significant differences in the rates of urinary tract infection and postoperative urinary retention (1.6% vs 0.6%; P = 0.391 and 4.3% vs 6.9%; P = 0.295, respectively) between the two groups, whereas a significant shorter length of hospital stay was observed in the non-urinary catheter group when compared to the urinary catheter group (4.61 ± 1.40 vs 5.23 ± 1.72; p < 0.001).

CONCLUSIONS

Our retrospective study provided evidence to the hypothesis that no placement of urinary catheter in patients with benign ovarian tumor was safe and feasible after single-port laparoscopic surgery. Meanwhile, avoiding urinary catheter could contributed to decrease in the length of hospital stay and is conducive to the enhanced recovery of patients.

Urinary Catheter Coating Modifications: The Race against Catheter-Associated Infections

Urinary catheters are common medical devices, whose main function is to drain the bladder. Although they improve patients’ quality of life, catheter placement predisposes the patient to develop a catheter-associated urinary tract infection (CAUTI). The catheter is used by pathogens as a platform for colonization and biofilm formation, leading to bacteriuria and increasing the risk of developing secondary bloodstream infections. In an effort to prevent microbial colonization, several catheter modifications have been made ranging from introduction of antimicrobial compounds to antifouling coatings. In this review, we discuss the effectiveness of different coatings in preventing catheter colonization in vitro and in vivo, the challenges in fighting CAUTIs, and novel approaches targeting host–catheter–microbe interactions.

Urinary catheters: history, current status, adverse events and research agenda

For more than 3500 years, urinary catheters have been used to drain the bladder when it fails to empty. For people with impaired bladder function and for whom the method is feasible, clean intermittent self-catheterization is the optimal procedure. For those who require an indwelling catheter, whether short- or long-term, the self-retaining Foley catheter is invariably used, as it has been since its introduction nearly 80 years ago, despite the fact that this catheter can cause bacterial colonization, recurrent and chronic infections, bladder stones and septicaemia, damage to the kidneys, the bladder and the urethra, and contribute to the development of antibiotic resistance. In terms of medical, social and economic resources, the burden of urinary retention and incontinence, aggravated by the use of the Foley catheter, is huge. In the UK, the harm resulting from the use of the Foley catheter costs the National Health Service between £1.0-2.5 billion and accounts for ∼2100 deaths per year. Therefore, there is an urgent need for the development of an alternative indwelling catheter system. The research agenda is for the new catheter to be easy and safe to insert, either urethrally or suprapubically, to be retained reliably in the bladder and to be withdrawn easily and safely when necessary, to mimic natural physiology by filling at low pressure and emptying completely without damage to the bladder, and to have control mechanisms appropriate for all users.

Strategies for the development of the urinary catheter

Indwelling urinary catheters are utilized in the management of a wide range of conditions both in an acute and a chronic setting. However, utilization of this type of device is associated with a number of issues, including an increased propensity to develop bacteriuria, symptomatic infection and also encrusted deposits on the device. The development of novel biomaterials, incorporation of therapeutic agents and other strategies to minimize the issues associated with these devices are discussed in this review.

Kink, flow and retention properties of urinary catheters part 2: novel design

Research has shown that all the current designs of urinary catheters based on natural latex or silicone rubber are susceptible to the major problems associated with their use--infection, encrustation and blockage. Research, to date, has focussed on the biological aspects of these complications; little research has been directed towards the contribution of the design or materials used in the manufacture of the catheters. The aim of the current study was to evaluate a totally new concept in catheter design based on nylon braid encased in a polyurethane matrix. Novel prototypes were tested using a range of established protocols to assess their flow properties, resistance to kinking and retention properties. The results were compared to those for the conventional latex and silicone based catheters currently in clinical use. The indications were that the new designs had superior flow properties and equivalent retention properties to the all-silicone catheters. Following further modification they also had superior resistance to kinking.