The complications and management of long-term indwelling catheters used for urinary retention and incontinence were reviewed. Research evidence from 1992 – 2002 was located through searches of CINAHL (38 articles), and Medline (89 articles). Fifty studies were critiqued for this review. The most common complications of long-term indwelling catheters are bacteriuria, encrustation, and blockage. Less common is the prevalence of bacteremia and renal disease. Risk factors for bacteriuria include female gender, older age, and long-term indwelling catheter use. Urinary white blood cells are the best indicator of urinary tract infection. For drainable catheter systems used by community dwelling adults, daily bag cleaning with a diluted bleach solution (1:10) is effective in reducing bacterial counts to negligible numbers. Application of topical antibiotic cream to the meatus around the catheter does not reduce bacteriuria. Silicone catheters and larger lumen size catheters are more resistant to encrustation than other catheter types and smaller lumen size catheters. Acidifying the urine without removing the urease-producing bacteria does not reduce encrustation. Removal of catheter blockage is preventive for renal disease. Because of the complications of long-term indwelling catheter usage, periodic assessment and voiding trials should be used to determine the continued need for a catheter. Evidence-based recommendations for managing indwelling urinary catheters include screening for risk factors and evaluating urinary white blood cell count for infection, and assessment of the continued need for a catheter. Interventions include consideration of closed versus open drainage systems, type of catheter, and size of catheter lumen.
Key words: urinary catheter, bacteriuria, encrustation, urinary tract infection
Donna Felber Neff, PhD, RN, CNS
The Sarah Cole Hirsh Institute for Best Nursing Practices of the Case Western Reserve University Frances Payne Bolton School of Nursing
The complications and management of long-term indwelling catheters used for urinary retention and incontinence were reviewed. Research evidence from 1992 – 2002 was located through searches of CINAHL (38 articles), and Medline (89 articles). Fifty studies were critiqued for this review. The most common complications of long-term indwelling catheters are bacteriuria, encrustation, and blockage. Less common is the prevalence of bacteremia and renal disease. Risk factors for bacteriuria include female gender, older age, and long-term indwelling catheter use. Urinary white blood cells are the best indicator of urinary tract infection. For drainable catheter systems used by community dwelling adults, daily bag cleaning with a diluted bleach solution (1:10) is effective in reducing bacterial counts to negligible numbers. Application of topical antibiotic cream to the meatus around the catheter does not reduce bacteriuria. Silicone catheters and larger lumen size catheters are more resistant to encrustation than other catheter types and smaller lumen size catheters. Acidifying the urine without removing the urease-producing bacteria does not reduce encrustation. Removal of catheter blockage is preventive for renal disease. Because of the complications of long-term indwelling catheter usage, periodic assessment and voiding trials should be used to determine the continued need for a catheter. Evidence-based recommendations for managing indwelling urinary catheters include screening for risk factors and evaluating urinary white blood cell count for infection, and assessment of the continued need for a catheter. Interventions include consideration of closed versus open drainage systems, type of catheter, and size of catheter lumen.
DOI: 10.3912/OJIN.Vol8No01HirshPsy01
https://doi.org/10.3912/OJIN.Vol8No01HirshPsy01
Key words: urinary catheter, bacteriuria, encrustation, urinary tract infection
Purpose
This systematic review is based on findings from research on long-term indwelling urinary catheters, including the related complications and management of the catheter system. The review includes laboratory studies and research on patients in a variety of settings including hospitals and nursing homes, with an emphasis on those who live in the community. Recommendations for best nursing practice based on the evidence are summarized.
Search Strategy
Research evidence from 1992-2002 was located through searches of CINAHL (38 articles) and Medline (89 articles). Fifty studies were critiqued for this review.
Key search terms were urinary catheter, meatal urinary, perineal urinary, skin urinary, urinary catheter irrigation, open system catheter, closed system catheter, urinary catheter infection, urinary catheter care, assessment, evidence based practice, bacteriuria, and urinary catheter encrustation.
Introduction
Urinary incontinence and urinary retention are the most common reasons for long-term indwelling urinary catheters (Warren, 1992). However, catheter related urinary tract infections (UTI) contribute to more than 40% of nosocomial hospital infections (Bronsema, Adams, Pallares, & Wenzel, 1993; Carapeti, Andrews, & Bentley, 1996; Classen, Larsen, Burke, & Stevens, 1991). In 1,540 nursing home residents, catheterized residents had three times the: risk of hospitalization, length of hospitalization, and length of antibiotic therapy compared to residents who were never catheterized (Kunin, Douthitt, Dancing, Anderson, & Moeschberger, 1992). Residents who were catheterized for 76 – 100% of their days in the nursing home were three times more likely to die within a year, compared to those who were never catheterized.
Of 54 hospitalized and home care patients with long-term indwelling catheters, 72% developed complications including: blockage (48%), leaking of urine around the catheter (37%), and frank episodes of hematuria (30%) (Kohler-Ockmore & Feneley, 1996). Community residents with long-term (> 3 months) indwelling catheters also had complications including blockage, urine leakage, and hematuria. In addition, they reported pain in the lower abdomen, urethra, penis, or vulva (Kohler-Ockmore & Feneley.
The mechanism of catheter-associated UTI, in a group of hospitalized patients, was determined as extra-luminal, in which the organisms migrated along the outside of the catheter (66%), and intra-luminal (34%), in which the bacteria migrated into the bladder as a result of opening the catheter system (Tambyah, Halvorson, & Maki, 1999).
Infection/ Bacteriuria
Patients with long-term indwelling catheters experience bacteriuria, and increasing length of catheterization is associated with higher levels of bacteriuria (Warren, 1992). Long-term catheterization (> 90 continuous days) also is associated with a higher incidence of chronic pyelonephritis and chronic renal inflammation (Warren, Muncie, Hebel, & Hall-Craggs, 1994). While elders with long-term indwelling catheters have persistent bacteriuria, few of these elders developed bacteremia or abnormal laboratory values following catheter replacement (Bregenzer et al., 1997). In a sample of 115 individuals with indwelling urinary or suprapubic catheters, nearly all were found to have polymicrobial bacteriuria (Jewes et al., 1998). Bacteriuria progressed to bacteremia in 10% of patients following suprapubic catheter replacements (Jewes et al.).
Two studies of hospitalized patients with catheter related UTI found that the majority were asymptomatic;
Urinary WBC count was the best predictor of catheter-associated UTI.
|
Elders residing in long-term care facilities or private homes have a high prevalence of chronic genitourinary symptoms and bacteriuria, and are at risk for urinary catheter associated infections (Bregenzer et al., 1997; Jewes et al., 1998; Orr et al., 1996). Functionally impaired elders with multiple co-morbidities may not have clinical signs and symptoms consistent with bacteriuria, and therefore standard diagnostic criteria may not be applicable to them (Orr et al.). Risk factors commonly associated with bacteriuria are female gender (Tambyah et al., 1999; Tambyah & Maki, 2000a; Tambyah & Maki, 2000b), older age, (Carapeti et al., 1996), and long-term catheter use (Hardyck & Petrinovich, 1998; Jewes et al.). Lack of systemic antibiotic therapy and positive meatal culture are additional risk factors for bacteriuria (Classen, Larsen, Burke, Alling, & Stevens, 1991; Huth, Burke, Larsen, Classen, & Stevens, 1992).
Type of catheter and use of antibiotic prophylaxis are thought to prevent infection, however, the research evidence is equivocal. Among adult, hospitalized patients (N = 1,309), male patients with silver-oxide coated catheters who did not receive antibiotics had higher rates of bacteriuria and staphylococcal species than male patients with non-silver coated catheters (Riley, Classes, Stevens, & Burke, 1995). In addition, 10% of men with silver-coated catheters had black discharge and irritation at the catheter insertion site.
In a laboratory study, all-silicone, hydrogel-silver coated silicone, and hydrogel-silver-coated latex catheters were compared for bacterial adhesion (Ahearn et al., 2000). The hydrogel-silver coated catheters had lower rates for bacterial adhesion than all-silicone catheters. Although the hydrogel-silver coated catheters are twice the cost of the all-silicone catheters, cost savings were realized related to decreased number of infections and the associated medical costs of treatment (Bologna et al., 1999; Karchmer, Giannetta, Muto, Strain, & Farr, 2000; Lai & Fontecchio, 2002; Reiche, Lisby, Jorgensen, Christensen, & Nordling, 2000).
Cranberry juice has been commonly used and recommended for management of UTIs. The research evidence does not support the effectiveness of cranberry juice for either prevention or treatment of UTIs. Drinking cranberry juice did not result in urine that was inhibitory to crystalline Proteus mirabilis, the cause of biofilms leading to encrustation (Morris & Stickler, 2001; Jepson, Mihaljevic, & Craig, 1998; 2001).
Encrustation
Catheter encrustation develops due to urease producing bacteria, such as Proteus mirabilis species, that elevates the urine pH. The lumen of the catheter becomes blocked by crystal formation from a combination of an elevated urine pH, bacterial film, and calcium and magnesium ions (Morris & Stickler, 1998; Morris, Stickler, & Winters, 1997). Proteus species have been associated with encrustation 24 hours after a glass bladder was inoculated (Stickler, Morris, Moreno, & Sabbuba, 1998). Acidification of the urine, without removal of the source of the urease, did not prevent encrustation (Bibby & Hukins, 1993).
In a laboratory model of the catheterized bladder, pooled human urine was collected and Jack Bean urease added to produce catheter encrustation (Getliffe, Hughes, & LeClaire, 2000). A Suby G solution (3.2% citric acid, 0.38% light magnesium oxide, 0.7% sodium bicarbonate, and 0.01% disodium edetate) was used in one or two sequential irrigations, using 100 ml or 50 ml of solution. Two sequential irrigations of 50 ml of solution were more effective than one irrigation with either 50 ml or 100 ml. In a second study, Suby G or a 1% mandelic acid solution reduced encrustation and improved mean patent luminal area of catheters more than 0.9% saline and no irrigation treatment (Getliffe, 1994b).
The effectiveness of three bladder irrigation treatments in preventing encrustation was explored in a group of female, elderly, long-term care patients with indwelling catheters (Kennedy, Brocklehurst, Robinson, & Faragher, 1992). The bladder irrigation solutions Suby G, Sodium Chloride, and Solution R were administered twice weekly for 3 weeks. Suby G contained 3.2% citric acid, 0.38% light magnesium oxide, 0.7% sodium bicarbonate, and 0.01% disodium edetate. The sodium chloride solution contained 0.9% sodium chloride. The Solution R contained 6% citric acid, 0.6% gluconolactone, 2.8% light magnesium carbonate, and 0.01% disodium edetate. The amount of encrustation was lowest following Suby G irrigations. Following the Suby G irrigations, there were more red bloods cells in the washout fluid than after the other two irritation solutions, indicating possible irritation to the bladder mucosa. However, no baseline measures of RBCs in urine samples were taken before irrigations. The irrigation solutions were similar in their ability to remove crystals at 10 days, but they had no effect on removal of bacteria or urease-producing bacteria.
Encrustation was least common in all-silicone catheters, compared to silicone-coated, latex, and Teflon-coated catheters (Kunin, Chin, & Chambers, 1987). In a laboratory model of the catheterized bladder, all-silicone catheters took longer to block than Teflon, silicon-coated, or hydrogel-coated catheters (Morris et al., 1997). However, the all-silicone catheter has a larger internal diameter (2.8 mm) compared to the hydrogel catheter (1.8 mm), so the longer time to blockage may be related to catheter diameter. One other study reported that all-silicone and hydrogel-coated catheters of equivalent diameters were equally resistant to encrustation (Cox, Hukins, & Sutton, 1988). Catheter blockage may pose a potential risk for kidney damage. In a mouse model, catheter blockage of 3 hours duration was associated with pyelonephritis and pyelitis (Johnson Russell, Lockatell, Zulty, & Warren, 1993). However, this has not been studied in humans.
Blockage
Catheter obstruction due to encrustation results in blockage of the catheter lumen (Getliffe, 1994a). Patients with long-term indwelling catheters who are prone to catheter blockage include those who require catheters for incontinence or urinary retention, need replacement of their catheters at intervals of less than 6 weeks (Getliffe), and have a history of bladder stones (Kohler-Ockmore & Feneley, 1996). Studies have reported conflicting findings about whether gender and mobility are related to catheter blockage (Burr & Nuseibeh, 1997; Choong, Hallson, Whitfield, & Fry, 1999; Getliffe; Kohler-Ockmore & Feneley). Other factors such as age, diagnosis, medication, bowel habits, smoking, fluid intake, catheter site, and catheter materials were not related to blockage (Burr & Nuseibeh; Getliffe; Kohler-Ockmore & Feneley).
Management of Catheters
Routine care of patients with indwelling catheters includes meatal care, bag emptying and decontamination, and catheter replacement.
[Research] results should discourage the use of topical antibiotic treatments for meatal care. |
Daily bag decontamination with a diluted (1:10) bleach solution has been found effective in reducing bacterial colony forming units to a negligible number (Dille & Kirchoff, 1993).
Bag decontamination and reuse were cost-effective and patients reported ease in following the procedure. |
Non-reusable/non-drainable catheter systems containing bacteria-inhibiting polymer intended for one time use have been associated with fewer UTIs than drainable catheter systems used in home care settings (Hardyck & Petrinovich, 1998). Costs for the individual non-drainable systems were higher than drainable systems, but overall costs related to number of UTI’s and hospitalizations were lower. The occurrence of bacteriuria in non-drainable, or closed systems, increased from 5% to 50% as length of catheter placement increased from 48 to 120 hours (Wille, Blusse van Oud alblas, & Thewessen, 1993).
Breaking or opening a closed system during routine care
The number of system openings was not related to the rate of bacteriuria. |
Catheter management was compared among 1,153 nurses, nursing assistants, geriatric aides and nursing students in hospitals, home care, and nursing home settings (Zimakoff, Pontoppidan, Larsen, Poulsen, & Stickler, 1995). Sterile technique was always used for intermittent catheterization in hospital and nursing home settings. However, 41% of the home care nurses used clean rather than sterile technique. Catheter systems were opened for: bag change, bladder irrigation, and to collect urine samples. Eighty-three percent of staff reported that they washed their hands after emptying drainage bags. Hospital staff more frequently reviewed the need to continue indwelling catheter use compared to nursing home and home care staff. Staff knowledge of written guidelines for catheter related procedures was greatest among hospital staff compared to nursing home and home care staff.
Reasons for catheter replacement in nursing home patients with indwelling catheters were: unintentional removal (43%), leakage (33%), or blockage (24%) (Muncie & Warren, 1990). On average, catheters were replaced three times per 100 patient days of catheterization.
Catheter-balloon fluid loss and changes in balloon diameter were examined in vitro (n = 20) and in vivo (n = 22 patients with catheterization > 10 days) (Barnes & Malone-Lee, 1986). In vitro, silicon-coated latex catheters retained balloon volumes better than all-silicone catheters. Of the 22 in vivo catheters, all but one needed to be replaced before 21 days, and all catheter balloons showed some deflation.
Because of the management difficulties and complications associated with long-term catheterization, periodic assessment should be made to determine whether a catheter could be removed. However, for patients who are bedbound and cared for in the home, the use of an indwelling catheter may be preferable to the possibility of skin breakdown associated with incontinence. Voiding trials are used to assess a patient’s ability to void after catheter removal. Surveys of urologic nurses regarding this practice found that 83% of respondents from hospitals, clinics, and home care, used voiding trials after catheter removal (Thees & Dreblow, 1999). All of the respondents reported using sterile water or normal saline to fill the bladder, and 75% used gravity flow to instill the fluid. Seventy percent of the respondents reported instilling fluid into the bladder until the patient expressed an urge to void. If a patient was unable to void immediately, respondents reported waiting 5 to 15 minutes for the patient to void. The voiding trial was considered successful if the patient was able to void, and the postvoid residual was < 150 ml.
A protocol for removal of indwelling urinary catheters was tested in 6 homebound adults over 60 years of age with indwelling catheters of 8 – 12 months duration (Weber, McDowell, Engberg, Brodak, & Donovan, 1998). Upon catheter removal, a visiting nurse performed twice daily catheterizations for post-voiding volume until the volumes were less than 100 ml. Two weeks following catheter removal, patients received biofeedback-assisted pelvic floor exercises for 8 weeks. Five patients reduced their incontinence by 71% to 100% and one patient had an indwelling catheter re-inserted due to skin breakdown.
Summary
Long-term indwelling urinary catheterization is associated with the complications of bacteriuria and UTI (Bronsema et al., 1993; Carapeti et al., 1996; Warren, 1992). Management techniques to decrease these complications include: systemic antibiotic prophylaxis (Riley et al., 1995), hydrogel-silver coated catheter use (Bologna et al., 1999), daily bag decontamination for drainable systems (Dille, & Kirchoff, 1993; Rooney, 1994), and use of non-drainable systems (Hardyck & Petrinovich, 1998). Other complications associated with long-term catheterization are encrustation and subsequent blockage (Kohler-Ockmore & Feneley, 1996). Encrustation was reduced with the use of all-silicone catheters compared to other catheter types (Kunin et al., 1987). Considering the complications of long-term catheterization, urinary catheter removal trials may help to decrease dependence on indwelling catheters. Evidence-based recommendations for managing patients with urinary catheters are summarized below in Table 1.
Table 1. Evidence-based Recommendations for Nursing Practice |
Assess patients related to:
Catheter management:
|
Author
Elizabeth Madigan, PhD, RN
e-mail: elizabeth.madigan@cwru.edu
Elizabeth Madigan received her PhD from Case Western Reserve University. She is Associate Dean for International Health and Associate Professor at the Frances Payne Bolton School of Nursing, Case Western Reserve University in Cleveland. Her research focus is on home health care outcomes and resource utilization using a health services research approach.
Donna Felber Neff, PhD, RN, CNS
e-mail: felber@uakron.edu
Donna Felber Neff received a PhD from Case Western Reserve University and is a gerontological clinical nurse specialist. Currently she is an Assistant Professor at the University of Akron’s College of Nursing. Dr. Neff’s research is focused on access to health care for vulnerable individuals.
The Sarah Cole Hirsh Institute for Best Nursing Practices of the Case Western Reserve University Frances Payne Bolton School of Nursing, Cleveland, Ohio, USA
http://fpb.cwru.edu/HirshInstitute
The Hirsh Institute's mission is to build a repository of best nursing practices based on research findings. Institute activities include: disseminating the most current scientific evidence on best nursing practices to clinicians, educators, administrators, and policy makers; guiding nursing research by identifying areas where scientific evidence is lacking; and conducting certificate programs for nursing staff to identify and implement evidence
Article published June 30, 2003
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