In vitro investigations into the formation and dissolution of infection-induced catheter encrustations

Washout policies in long-term indwelling urinary catheterisation in adults

BACKGROUND

People requiring long-term bladder draining with an indwelling catheter can experience catheter blockage. Regimens involving different solutions can be used to wash out catheters with the aim of preventing blockage. This is an update of a review published in 2010.

OBJECTIVES

To determine if certain washout regimens are better than others in terms of effectiveness, acceptability, complications, quality of life and critically appraise and summarise economic evidence for the management of long-term indwelling urinary catheterisation in adults.

SEARCH METHODS

We searched the Cochrane Incontinence Group Specialised Trials Register, which contains trials identified from the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, MEDLINE In-Process, MEDLINE Epub Ahead of Print, CINAHL, ClinicalTrials.gov, WHO ICTRP and handsearching of journals and conference proceedings to 23 May 2016. We also examined all reference lists of identified trials and contacted manufacturers and researchers in the field.

SELECTION CRITERIA

All randomised and quasi-randomised trials comparing catheter washout policies (e.g. washout versus no washout, different washout solutions, frequency, duration, volume, concentration, method of administration) in adults (aged 16 years and above) in any setting (i.e. hospital, nursing/residential home, community) with an indwelling urethral or suprapubic catheter for more than 28 days.

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted data. Disagreements were resolved by discussion. Data were assessed and analysed as described in the Cochrane Handbook. If data in trials were not fully reported, clarification was sought from the study authors. For categorical outcomes, the numbers reporting an outcome were related to the numbers at risk in each group to derive a risk ratio (RR). For continuous outcomes, means and standard deviations were used to derive mean differences (MD).

MAIN RESULTS

We included seven trials involving a total of 349 participants, 217 of whom completed the studies. Three were cross-over and four were parallel-group randomised controlled trials (RCTs). Of these, two trials were added for this update (one parallel-group RCT with 40 participants and one cross-over RCT with 67 participants). Analyses of three cross-over trials yielded suboptimal results because they were based on between-group differences rather than individual participants' differences for sequential interventions. Two parallel-group trials had limited clinical value: one combined results for suprapubic and urethral catheters and the other provided data for only four participants. Only one trial was free of significant methodological limitations, but there were difficulties with recruitment and maintaining participants in this study.The included studies reported data on six of the nine primary and secondary outcome measures. None of the trials addressed: number of catheters used, washout acceptability measures (including patient satisfaction, patient discomfort, pain and ease of use), or health status/measures of psychological health; very limited data were collected for health economic outcomes. Trials assessed only three of the eight intervention comparisons identified. Two trials reported in more than one comparison group.Four trials compared washout (either saline or acidic solution) with no washout. We are uncertain if washout solutions (saline or acidic), compared to no washout solutions, has an important effect on the rate of symptomatic urinary tract infection or length of time each catheter was in situ because the results are imprecise.Four trials compared different types of washout solution; saline versus acidic solutions (2 trials); saline versus acidic solution versus antibiotic solution (1 trial); saline versus antimicrobial solution (1 trial). We are uncertain if type of washout solution has an important effect on the rate of symptomatic urinary tract infection or length of time each catheter was in situ because the results are imprecise.One trial compared different compositions of acidic solution (stronger versus weaker solution). We are uncertain if different compositions of acidic solutions has an important effect on the rate of symptomatic urinary tract infection or length of time each catheter was in situ because only 14 participants (of 25 who were recruited) completed this 12 week, three arm trial.Four studies reported on possible harmful effects of washout use, such as blood in the washout solution, changes in blood pressure and bladder spasms.There were very few small trials that met the review inclusion criteria. The high risk of bias of the included studies resulted in the evidence being graded as low or very low quality.

AUTHORS' CONCLUSIONS

Data from seven trials that compared different washout policies were limited, and generally, of poor methodological quality or were poorly reported. The evidence was not adequate to conclude if washouts were beneficial or harmful. Further rigorous, high quality trials that are adequately powered to detect benefits from washout being performed as opposed to no washout are needed. Trials comparing different washout solutions, washout volumes, and frequencies or timings are also needed.

Washout policies in long-term indwelling urinary catheterisation in adults

BACKGROUND

People requiring long-term bladder draining with an indwelling catheter can experience catheter blockage. Regimens involving different solutions can be used to washout catheters with the aim of preventing blockage.

OBJECTIVES

To determine if certain washout regimens are better than others in terms of effectiveness, acceptability, complications, quality of life and economics for the management of long-term indwelling urinary catheterisation in adults.

SEARCH STRATEGY

We searched the Cochrane Incontinence Group Specialised Trials Register, MEDLINE, MEDLINE In-Process & Other Non-Indexed Citations, CINAHL and EMBASE (searches last updated April 2009). Additionally, we examined all reference lists of identified trials.

SELECTION CRITERIA

All randomised and quasi-randomised trials comparing catheter washout policies (e.g. washout versus no washout, different washout solutions, frequency, duration, volume, concentration, method of administration) in adults (16 years and above) in any setting (i.e. hospital, nursing/residential home, community) with an indwelling urethral or suprapubic catheter for more than 28 days.

DATA COLLECTION AND ANALYSIS

Data were extracted by three reviewers independently and compared. Disagreements were resolved by discussion. Data were processed as described in the Cochrane Handbook. If the data in trials were not fully reported, clarification was sought from the authors. For categorical outcomes, the numbers reporting an outcome were related to the numbers at risk in each group to derive an risk ratio (RR). For continuous outcomes, means and standard deviations were used to derive weighted mean differences (WMD). No meta-analysis of study results was possible.

MAIN RESULTS

Five trials met the inclusion criteria involving 242 patients (132 completed) in two cross-over and three parallel-group randomised controlled trials. Only three of the eight pre-stated comparisons were addressed in these trials. Some trials addressed more than one comparison (e.g. washout versus no washout and one type of washout solution versus another). The analyses reported for the two cross-over trials were inappropriate as they were based on differences between groups rather than differences within individuals receiving sequential interventions. Two parallel-group trials had limited value: one combined results for suprapubic and urethral catheters and one had data on only four participants. Only one trial was free of significant methodological limitations, but its sample size was small.Three trials compared no washout with one or more washout solution (saline or acidic solutions) and authors tended to conclude no difference in clinical outcomes between washout and no washout. In the one trial which had data of sufficient quality to allow interpretation, no difference was detected between washout and no washout groups in the rate of symptomatic urinary tract infection or time to first catheter change. Three trials compared different types of solution: saline versus acidic solutions (two trials); saline versus acidic solution versus antibiotic solution (one trial). Authors tended to report no difference between different washout solutions but the data were too few to support their conclusions. The one trial which warranted consideration concluded no difference between saline and an acidic solution in terms of symptomatic urinary tract infections or time to first catheter change.

AUTHORS' CONCLUSIONS

The data from five trials comparing differing washout policies were sparse and trials were generally of poor quality or poorly reported. The evidence was too scanty to conclude whether or not washouts were beneficial. In the first instance we require further rigorous, high quality trials with adequate power to detect any benefit from washout being performed as opposed to none. Then trials comparing different washout solutions, washout volumes, frequencies/timings and routes of administration are needed.

Life with an indwelling urinary catheter: the dialectic of stigma and acceptance

The purpose of this hermeneutic phenomenology was to describe and interpret the lived experience of long-term users of urinary catheters. Living with a urinary catheter involved a dialectical swing between acknowledgment that the catheter was "a part of me" and feelings of alienation and vulnerability when it was experienced as a stigma. Themes include Adjusting to embodied changes by perceiving the catheter as a "part of me," Shame and responding to shame by normalizing, and Embarrassment and coping with embarrassment by humor. Providers can minimize stigma related to the visibility of the catheter by coaching patients in strategies to manage going out of the home with a minimum of urine accidents or by helping develop ways to conceal the urine bag.

Urine flowing: a phenomenological study of living with a urinary catheter

The experience of living with a long-term urinary catheter was investigated with a community-dwelling sample of 14 adults ranging in age from 35 to 95 who had worn a catheter for 6 months to 18 years. Data were obtained by audiotaped face-to-face interviews. Merleau-Ponty's phenomenology and van Manen's methodology guided the study. Living with a urinary catheter was found to be like living with the forces of flowing water. People were keenly aware of the flow of urine through their catheters, and they noticed when their bags needed emptying or when urine drainage seemed sluggish or obstructed. The metaphor of urine flowing like water may provide a teaching heuristic for assisting clients in adjusting to living with a catheter. Implications for further research focus on understanding the relationship between sensitivity to the dynamics of urine flow and urinary tract infection.

Importance of pH monitoring in the care of long-term catheters

One of the main complications encountered by patients with long-term in-dwelling catheters is that of catheter blockage as a result of encrustation. This is usually managed at a district nurse level by the administration of catheter maintenance solutions (CMSs) or frequent catheter changes. However, catheter changes and maintenance solutions are often only employed after blockage has occurred. Regular recording of catheter care and urinary pH monitoring can be utilized to optimize the management of long-term catheters and plan catheter changes and CMS administration in a prophylactic manner. This article reviews the literature regarding CMS and urinary pH and demonstrates how the introduction of continued and formalized recording of catheter care and pH monitoring can improve long-term catheter management.

Catheter associated urinary tract infection and encrustation

This paper examines the relationship between urinary pH, infection and urinary catheter encrustation and discusses the current management and problems of catheter associated urinary infection and encrustation.

Urinary catheters: selection, management and prevention of infection

Urinary catheterization is a common procedure for both hospital and community patients. Nurses make many of the decisions in regard to both catheter selection and subsequent catheter care. These decisions, for example, in the type of catheterization (intermittent, indwelling, urethral or suprapubic) should be made on an informed basis. Choosing the optimum catheter material and size can benefit catheter care. Encrustation can be a problem for some catheterized patients and nurses are often involved in trying to prevent or treat it. This and other aspects of catheter management including infection control, constipation and meatal hygiene are discussed.

Determination of 5-hydroxy-N-methylpyrrolidone and 2-hydroxy-N-methylsuccinimide in human urine

A method for simultaneous determination of 5-hydroxy-N-methylpyrrolidone and 2-hydroxy-N-methylsuccinimide in urine is described. These compounds are metabolites of N-methyl-2-pyrrolidone, a powerful and widely used organic solvent. 5-Hydroxy-N-methylpyrrolidone and 2-hydroxy-N-methylsuccinimide were purified from urine by adsorption to a C8 solid-phase extraction column and then elution by ethyl acetate-methanol (80:20). After evaporation, the samples were derivatised at 100 degrees C for 1 h by bis(trimethylsilyl)trifluoroacetamide. Ethyl acetate was then added and the samples were analysed by gas chromatography-mass spectrometry in the electron impact mode. The extraction recovery for 5-hydroxy-N-methylpyrrolidone was about 80% while that for 2-hydroxy-N-methylsuccinimide was about 30%. The intra-day precision for 5-hydroxy-N-methylpyrrolidone was 2-4% and the between-day precision 4-21% (4 and 60 microg/ml). The intra-day precision for 2-hydroxy-N-methylsuccinimide was 4-8% and the between-day precision 6-7% (2 and 20 microg/ml). The detection limit was 0.2 microg/ml urine for both compounds. The method is applicable for analysis of urine samples from workers exposed to N-methyl-2-pyrrolidone.

Long-term indwelling urinary catheter care: conceptualizing the research base

The traditional public health concepts of agent, host, and environment can provide a useful interdisciplinary model for analysing the current state of knowledge in long term indwelling urinary catheter care. A broad review of literature about urinary catheter care was carried out to identify major areas of research and gaps in knowledge. Most research in the past decade has focused on understanding how catheter encrustations develop and how such encrustations may contribute to leaking/blocking of the catheter and urinary tract infection. Two tables are presented which summarize research related to the development of sediment/encrustation of the catheter and to irrigation of the catheter. Nevertheless, many areas related to catheter care have not been studied extensively. The patient's perspective is one such area. Other areas that have not been studied in depth include care of the drainage bag and the role of fluid intake. These under-studied concerns relate to environmental factors with which the nurse is directly involved, namely, asepsis and hydrokinetic forces. Further conceptualization of the nursing role in long-term urinary catheter care might aid in the development of nursing theories that could be tested to understand how best to help people manage these catheters.

Treatment options in struvite stones

Urinary calculi have plagued man over the centuries. The epidemiology and pathogenesis of infection have been studied. The curative treatment remains problematic. Without therapy, a vicious cycle of stone formation occurs. This results in renal damage and even death. Multimodality therapy is the key. Nonoperative treatment leads to progressive renal damage. The combination of maximal surgical ablation and medical therapy is synergistic. The combination of PCNL-ESWL has not appeared to produce ill effects. PCNL-ESWL is a less morbid surgical alternative than open surgical procedures. Adjunctive medical therapy, such as culture-specific antibiotics and urease inhibitors, complements surgical ablation by reducing the morbidity with persistent UTIs and stone recurrence. The urologist today must approach struvite staghorns with a vast armamentarium of surgical and medical techniques. Each patient requires a unique solution.

Complications of urinary tract infections associated with devices used for long-term bladder management

The long-term indwelling urethral catheter continues to be a major cause of morbidity in patients in hospitals, nursing homes and home care. Many authorities have recommended that wherever possible, alternative techniques should be considered for the management of patients with urinary retention or incontinence. This article considers the complications that develop from the urinary tract infections associated with long-term indwelling catheterization and reviews the evidence that the other options for bladder management pose less serious threats to health.