Complications of Chronic Indwelling Urinary Catheters Among Male Nursing Home Patients: A Prospective Study

0022-5347 /87 /1385-1191$02.00/0 Vol. 138, November

THE JOURNAL OF UROLOGY

Copyright© 1987 by The Williams & Wilkins Co.

Printed in U.S.A.

COMPLICATIONS OF CHRONIC INDWELLING URINARY CATHETERS AMONG MALE NURSING HOME PATIENTS: A PROSPECTIVE STUDY JOSEPH G. OUSLANDER, BARBARA GREENGOLD

AND

SOPHIA CHEN

From the Veterans Administration Medical Center, Sepulveda and UCLA School of Medicine, Los Angeles, California

ABSTRACT

We studied prospectively the incidence of symptomatic infections of presumed urinary tract origin requiring antimicrobial therapy among 54 male nursing home patients with chronic indwelling bladder catheters. During 514 patient-months at risk there were 106 episodes of symptomatic infection, for an incidence of 0.21 per patient-month at risk. Of the patients 80 per cent had at least 1 episode and 48 per cent had 2 or more. None of the clinical factors we examined, including age, nutritional status, stool incontinence, diabetes mellitus, episodes of catheter blockage and the use of chronic suppressant antimicrobial therapy, was associated with the development of symptomatic infection. Further research on host and pathogen-related factors that increase the risk for symptomatic infection, and improvements in infection control and catheter care protocols are necessary to decrease catheter-associated morbidity among male nursing home patients who must be managed by chronic indwelling catheterization. (J. Ural., 138: 1191-1195, 1987) Despite limited indications, indwelling urinary catheters are used to manage urinary incontinence in many nursing home patients.1-4 Several studies have found that a specific cause of urinary incontinence rarely is sought among these patients and that clear indications for indwelling catheter use are not well documented. 2•5• 6 Appropriate indications for the use of chronic indwelling urinary catheters, such as an acontractile neurogenic bladder and surgically uncorrectable urinary retention, are more common among male than female nursing home patients. In a survey of 90 Veterans Administration nursing homes at which 95 per cent of the patients were men 41 per cent of the patients were identified as incontinent of urine and 22 per cent of these were being managed by an indwelling catheter. 7 This finding compares to a rate of 2 per cent for indwelling catheter use among patients at some nonprofit and academically affiliated nursing homes, at which the prevalence of incontinence is 40 to 60 per cent but nearly 75 per cent of the patients are women. 1·2 The incidence of morbidity and mortality associated with short-term indwelling catheterization (that is days to a few weeks), as well as the high prevalence of polymicrobial and frequently changing bacteriuria associated with chronic indwelling catheter use have been well documented.B-12 However, the incidence of infectious complications during a 12-month period among male nursing home patients with chronic indwelling catheters has not been studied prospectively. The latter data are important because of the rapidly growing nursing home population, and the substantial impact the complications of indwelling catheter use could have on the morbidity, mortality and costs of caring for these patients. 13 We determine prospectively the incidence of symptomatic urinary tract infection among male nursing home patients with chronic indwelling urinary catheters and attempt to identify factors associated with symptomatic urinary tract infection that might be helpful to develop and target preventive measures. METHODS

The study was done at an academically affiliated Veterans Administration nursing home at which medical care was pro-

vided by nurse practitioners with training in geriatrics plus house staff from the department of medicine under the supervision of faculty in the division of geriatric medicine. During the study interval the average census was 182 patients, of whom 95 per cent were men. This population has been characterized in detail previously14 and it is composed predominantly of patients with severe impairments of cognitive and/or physical functioning resulting from a variety of neurological disorders, including primary and secondary dementia, stroke, traumatic injuries of the central nervous system and multiple sclerosis. On average, 32 per cent of the men were continent of urine, 6 per cent were incontinent and managed without a catheter, 7 per cent were incontinent and managed by external catheters worn at night only, 27 per cent were incontinent and managed by external catheters worn continuously, and 28 per cent (41 per cent of the noncontinent men) were managed by continuous indwelling catheters. From March 1985 through February 1986 all men with continuous indwelling catheters were followed until they were discharged from the facility or died, or the catheter was removed. Latex 14 or 16F 3-way Foley catheters were used. Standard protocols were done by the nursing staff for catheter care, which included daily soap and water cleansing of the catheter entry site, irrigation only for catheter blockage and routine changing of the catheter every 4 to 6 weeks. One of us (B. G.) collected demographic, clinical, functional and nutritional status data from the medical records of each patient. Catheter blockages and symptomatic urinary tract infections were identified by regular record reviews, and direct discussions with the nurses, nurse practitioners and physicians caring for the patients. Only catheter blockages that required re-insertion of a new catheter after attempts at irrigation were noted. Routine urinalyses and cultures were not done, since data at our institution as well as in the literature have indicated that almost 100 per cent of the patients with chronic indwelling catheters have significant bacteriuria that changes frequently. B-12 Symptomatic urinary tract infection was based on 4 criteria and defined as an episode in which 1) the patient had 1 or more symptoms or signs of a urinary tract infection (in this patient population these symptoms usually were fever of 102F or greater with prominent changes in mental status and/or state of consciousness), 2) other sources of fever had been excluded

Accepted for publication April 21, 1987. Supported by Academic Award AG00189 from the National Institute on Aging. 1191

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OUSLANDER, GREENGOLD AND CHEN

carefully by history and physical examination performed by a nurse practitioner and/or a physician, and laboratory studies (usually a chest x-ray), 3) the patient was treated with an antimicrobial for a urinary source of infection and 4) a urine culture yielded 105 colony-forming units of at least 1 urinary pathogen. There were several episodes in which criteria 1 to 3 were met but the urine culture either was lost, not sent until after treatment had been initiated (and, therefore, was sterile or yielded only yeast) or not sent at all. Each of the latter episodes was reviewed individually and included as a symptomatic urinary tract infection if criteria 1 to 3 were met, a fever of 102F was present, and physical examination, chest x-ray and the clinical course excluded a lower respiratory or other documented source of infection (that is a pressure sore). Courses of antimicrobial therapy for nonurinary sources (usually lower respiratory) were recorded. Episodes in which the patient was treated for a lower respiratory infection and a urinary tract infection simultaneously were not counted as a symptomatic urinary tract infection. To identify factors associated with the development of symptomatic urinary tract infection, simple regression was performed on continuous measures versus the number of symptomatic urinary tract infections among all patients. The patients then were subdivided into those who had no, 1 or more and 2 or more symptomatic urinary tract infections, and they were compared by t tests for continuous data and chi-square tests for categorical data. Fischer's exact test was used when cell size was 6 or less. RESULTS

During the 12-month study period 54 patients (47 with urethral and 7 with suprapubic catheters) were followed for a mean of 9.5 months. Of the patients 31 (57 per cent) were followed for all 12 months, while 20 per cent of the remainder entered the nursing home during the study period and they were followed until the end of the study, 13 per cent died, 6 per cent were discharged from the nursing home and 4 per cent had the catheter removed. The total number of months at risk among all patients was 514. Table 1 shows selected characteristics of the 54 patients. Most patients had the catheters to manage urinary retention. Although it was not possible to determine precisely the duration of catheterization, records were reviewed as far back as possible (for more than 10 years in some cases) until the time the catheter was inserted or until records no longer were available. During the prospective period there were 106 episodes of symptomatic urinary tract infection. Figure 1 illustrates the distribution of these episodes among all 54 patients. Only 11 patients (20 per cent) did not have at least 1 episode. The proportion of patients who did not have at least 1 episode was higher among the 23 patients followed for less than 12 months (30 per cent, mean followup 8.7 months) than among the 31 followed for all 12 months (13 per cent). The over-all incidence of these episodes was tl.21 per patient-month at risk or 0.69 per 100 days (using an average of 30 days per month). Interestingly, when we reviewed the medical records of these 54 patients as far back as we could during the time before the study, the incidence of episodes for which these patients appeared to have been treated for symptomatic urinary tract infection was similar (199 episodes in 1,010 patient-months, or 0.20 per month). These rates are much higher than in the patients without indwelling catheters who were at the facility at the same time. With the same data collection methods and definitions, 176 patients without indwelling catheters were followed for 862 patient-months during which 48 symptomatic urinary tract infections occurred (0.06 per month). The mean number of symptomatic urinary tract infections among the 54 patients with indwelling catheters was 1.96 (standard deviation 1.85, range Oto 8). The 7 patients with suprapubic catheters had a higher mean number of episodes (2.86) than the 47 with ure-

TABLE

1. Selected characteristics of sample

Age* Mos. in nursing home* Reason for catheter(%): Urinary retention owing to obstruction Urinary retention owing to acontractile neurogenic bladder Manage incontinence Skin protection Uncertain Mos. of catheterization*· t No. genitourinary diagnoses (% )::j: None 1 2

70.5 ± 14.9 (39-104) 46 ± 125 (1-920) 15 39 22 11

13 21 ± 30 (1-54)

7 33 43 17 61

.;;3 Stool incontinence ( %) Diabetes (%): Insulin dependent Oral agent Diet controlled Body wt.:* Total pounds % of ideal Serum creatinine (mg./100 ml.)* Hemoglobin (gm./100 ml.)* Albumin (gm./100 ml.)* On prophylactic antibiotic (% )§ On urinary acidifier ( %) II

6 2 6

142 ± 90 ± 1.16 ± 12.8 ± 3.56 ±

34 (85-234) 16 (60-131) 0.39 (0.4-2.1) 1. 7 (8.9-16.3) 0.47 (2.3-4.3) 22 28

Normal values were 0.7 to 1.4 mg./dl. for serum creatinine, 14-16 gm./dl. for hemoglobin and 3.4 to 5.0 gm./dl. for albumin. * Mean ± standard deviation (range). t It was not possible to determine the precise duration of catheterization for all patients. :j: Benign prostatic hyperplasia, recurrent urinary tract infection, prostatic or bladder carcinoma, surgical procedure(s), bladder stone, pelvic irradiation and neurogenic bladder (acontractile). § Trimethoprim-sulfamethoxazole for at least half of the months they were followed. II Ascorbic acid and/or methenamine for at least half of the months they were followed; 3 patients were on an antibiotic plus an acidifier.

ONE 32% ~

NONE 20%

MORE

\ THREE 15% Distribution of symptomatic infections in study population. Percentages refer to proportion of patients with given number of symptomatic episodes during prospective study period.

thral catheters (1.83) but this difference did not reach statistical significance (p = 0.17), and it was largely owing to 2 patients in the suprapubic group (1 who had 7 episodes and 1 who had 5). Although moderately ill patients requiring intravenous fluids and parenteral antibiotics usually were treated at the nursing home, 7 of the 106 episodes (7 per cent) resulted in hospitalization. None of these 7 patients died. Of the 54 patients 7 (13 per cent) died during the prospective study period and only 2 of these deaths were related temporally to treatment of symptomatic urinary tract infection. It is possible that 1 or 2 of the other deaths, which were sudden and for which autopsies were not obtained, could have been related to urosepsis. Thus, the 1-year mortality rate for catheter-related urosepsis among

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COMPLICATIONS OF CHRONIC INDWELLING URINARY CATHETERS

the 54 patients ranged from 4 to 7 per cent. There were 22 episodes of catheter blockage in 19 patients (33 per cent). No episode of traumatic removal of the catheter (that is by the patient himself or inadvertently) was reported during the study period. Culture reports were available for 86 of the 106 episodes (81 per cent) of symptomatic urinary tract infection. Of the reports 35 (41 per cent) indicated significant growth (more than 105 colony-forming units) of more than 1 urinary pathogen. The proportion of cultures with significant growth of more than 1 organism probably would have been higher had we asked the microbiology laboratory specifically to identify and to quantitate each organism separately. The most common pathogens reported were (by percentage of cultures) Proteus species 31 per cent, Escherichia coli 26 per cent, enterococcus 22 per cent, Pseudomonas species 20 per cent, Providentia species 15 per cent, Klebsiella species 8 per cent and Citrobacter species 6 per cent. Simple regression analyses showed no significant relationship between number of symptomatic urinary tract infections and all of the continuous measures we examined, including age, duration of catheterization, number of genitourinary diagnoses, number of catheter blockages, total body weight, percentage of ideal body weight, and serum creatinine, hemoglobin and albumin levels. There also were no significant differences in the mean value of any of the continuous measures when patients who had 1 or more symptomatic urinary tract infections (43) were compared to those who had none (11). Similarly, no significant differences were identified when those with 2 or more symptomatic urinary tract infections (26) were compared to those with none or 1 (28). Table 2 compares several other characteristics of the patients who did versus those who did not have at least 1 symptomatic urinary tract infection. The only significant association indicates that a higher proportion of patients with a serum albumin of less than 3.5 gm./100 ml. had at least 1 symptomatic infection than those with a serum albumin of 3.5 mg./100 ml. or higher. This association was no longer significant when a cutoff of 3.2 gm./100 ml. was used (chi-square 2.13, p >0.05) or when the patients were divided into those with 2 or more and those with 1 or more symptomatic urinary tract infections. In the latter analyses none of the other characteristics listed in table 2 was associated with the development of 2 or more symptomatic urinary tract infections. DISCUSSION

Our prospective study has documented a seemingly high incidence of symptomatic urinary tract infection among male nursing home patients with chronic indwelling urinary catheters. Of the 54 patients followed 80 per cent had at least 1 episode and 48 per cent had 2 or more during a mean followup of 9.5 months; the average number of episodes per patient during this period was approximately 2. Although only 7 of the 106 symptomatic urinary tract infections led to hospitalization, the morbidity and costs in terms of hospitalization and related complications could have been substantially higher had these patients not been in an academic nursing home program that had significantly reduced acute hospitalizations during the year before the study. 14 There are few data against which the incidence of symptomatic urinary tract infection in our patient population can be compared directly. Although there have been numerous studies of nosocomial infections in nursing homes, almost all of these are either retrospective or 1-day prevalence surveys. 1 5-19 All have found that urinary tract infections are among the 2 or 3 most common nosocomial infections in this setting. In 2, 1-day prevalence surveys of non Veterans Administration facilities, the prevalence of symptomatic urinary tract infection was 2.6 per cent; 16 in 1 of them 13 per cent of the patients with indwelling catheters had a symptomatic urinary tract infec-

TABLE

2. Comparison of patients who did versus those who did not

have a symptomatic urinary tract infection Characteristic Age: <65 65+ Diabetes: Yes No Stool incontinence: Yes No Hemoglobin (gm./100 ml.): <13 ;;:;13 <11 ;;:;11 Albumin (gm./100 ml.): <3.5 sa:;3.5 <3.2 sa:;3.2 History of urinary retention: Yes No Catheter blockage(s): ;;:;1 None Urinary acidifier: Yes No Prophylactic antibiotic: Yes No Antibiotic therapy for nonurinary source during study period: Yes No

No. Pts.

% WhoHadsa:;l Symptomatic Infections

P Value

20 34

80 79

Not significant

7 47

100 77

Not significant

33 21

73 90

Not significant

31 24

77 83

Not significant

8 46

75 80

Not significant

16 38

94 74

<0.05

11 43

91 77

Not significant

29 25

83 76

Not significant

18 36

78 81

Not significant

15 39

87 77

Not significant

12 42

75 81

Not significant

30 24

83 75

Not significant

Comparisons were done by chi-square analysis. When cell size was less than 6 Fischer's exact method was used. Comparisons also were made between patients who had 2 or more symptomatic urinary tract infections and those who had 1 or none, and mean values for continuous measures among all of these patient subgroups.

tion. 16 In a prospective study of a Veterans Administration chronic care facility the incidence of symptomatic urinary tract infection was 0.22 per 100 patient care days 18 but it was not clear in this study what proportion of patients had catheters. Three retrospective studies have reported the incidence of symptomatic infections in Veterans Administration nursing home patients with indwelling catheters; 19- 21 2 of them were done at the Wood Veterans Administration facility in Milwaukee. In these 3 studies 48 per cent of 23 catheterized men had at least 1 symptomatic infection within 1 year, 19 24 per cent of 37 men with indwelling catheters had a symptomatic infection during 1 month20 and 20 symptomatic urinary tract infections were found among 10 chronically catheterized patients during 223 patient-months of observation (a rate of 0.09 per patientmonth at risk). 21 Only 2 prospective studies have examined carefully the incidence of symptomatic urinary tract infection in chronically catheterized nursing home patients. In a study comparing monthly to. as needed catheter changes among 17 men 3 of 10 in the monthly change group and 6 of 7 in the as needed change group had a symptomatic infection within 6 months, for an incidence rate of 0.4 to 1.0 during the 6 months. 22 In a recent prospective study of 47 elderly chronically catheterized women in 2 nursing homes 32 (68 per cent) had 98 fevers of possible urinary tract origin, for an over-all incidence of 1.1 fevers per 100 patient-days; the incidence of fevers was significantly higher on days when catheter obstruction occurred (6.7 per 100). 23 Most of the fevers were less than 101F and shortlived, and only 14 (0.16 per 100 patient-days) were treated with

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antibiotics. Although none of the fevers prompted hospitalization, death occurred during 6 of the episodes. 23 Our data suggest a somewhat higher incidence of symptomatic urinary tract infection requiring treatment than the studies of smaller numbers of chronically catheterized male nursing home patients cited, and a substantially higher incidence (0.69 versus 0.16 per 100 days) than the study of female nursing home patients. 23 While it is possible that our definition of symptomatic infection, and the ready availability of medical evaluation and treatment at our nursing home led to an overestimate of the incidence of symptomatic urinary tract infection, we do not believe that this is the case. Each of the episodes we included was associated with a high fever and at least 1 other symptom or sign (most commonly altered mental status), and almost all of the patients required parenteral antibiotic therapy before the fever defervesced. The higher incidence in male versus female catheterized patients largely may be related to the higher potential for men to have chronic prostatitis, prostatic and periurethral abscesses, and epididymitis. We were unable to find any specific characteristics that were associated with the development of symptomatic urinary tract infection in our patient population. Such associations might have been detected had we studied a larger group of patients during a longer period. Given our sample size and the prevalence of the various characteristics we examined, the statistical power to detect such associations was relatively low (less than 0.60 for most). 24 Although a statistical association between catheter blockage and symptomatic urinary tract infection was not found, our data collection methods and conservative definition of catheter blockage may have led us to miss such an association. Of the 22 episodes of catheter blockage that we identified in 18 patients at least 6 were followed immediately by a symptomatic episode. As a result of this observation, after this study was completed we began to treat patients routinely with catheter blockage with a 48 to 72-hour intramuscular course of an aminoglycoside. A prospective study of the efficacy of some type of prophylactic regimen for catheter changes related to catheter blockage would be of value, especially given the lack of consensus on the efficacy of antimicrobial prophylaxis for other urological procedures. 25 Similar to previous studies that have shown no benefit of routine antimicrobial prophylaxis in patients with short-term indwelling catheters,s-10• 26• 27 we were unable to document any association between the routine use of either urinary acidifiers or antimicrobials, and the development (or lack of development) of symptomatic urinary tract infection. Although a much larger and randomized controlled study would be needed to document clearly the lack of efficacy of this practice, we would agree with the recommendations discouraging the use of prophylactic antimicrobials because of the potential to contribute to the development of resistant organisms.s-10 This could become a major problem in nursing homes at which infection control practices are not well developed. 28 The need for chronic indwelling urinary catheter use among a subgroup of nursing home patients, especially men, will persist. Intermittent catheterization, although practical and effective in paraplegics and elderly noninstitutionalized women, 29 is likely to be impractical, uncomfortable and result in a high risk of infection among many institutionalized men. Thus, further study is needed to identify patients at highest risk for complications from long-term indwelling catheterization and to develop effective preventive measures that can be targeted towards those at highest risk. Recent studies have begun to examine the role of rectal colonization and bacterial adherence properties in the pathogenesis of catheter-associated bacteriuria,30- 31 as well as a variety of host factors in the pathogenesis and susceptibility to urinary tract infection. 32 Until these types of studies lead to better preventive measures, the prevention of infectious complications from chronic indwelling catheters among nursing home patients will depend to

a large extent on 2 basic strategies: 1) as Beeson noted nearly 30 years ago33 and as Kunin recently re-emphasized in relation to nursing homes,4 the use of indwelling catheters should be limited to only those patients with appropriate indications and 2) as suggested by a recent study in which fewer interruptions in the drainage system reduced morbidity and mortality significantly among catheterized patients in the acute hospital setting, 34 improvements in nursing home infection control policies28 and catheter care protocols7• 35 may go a long way towards making the indwelling catheter safer for those nursing home patients who are managed best by this device. Lynda Burton assisted with the statistical analyses. Drs. John Warren, Tom Yoshikawa and Dean Norman provided thoughtful review of and suggestions for the manuscript. REFERENCES 1. Marron, K. R., Fillit, H., Peskowitz, M. and Silverstone, F. A.: The nonuse of urethral catheterization in the management of urinary incontinence in the teaching nursing home. J. Amer. Geriatr. Soc., 31: 278, 1983. 2. Ouslander, J. G., Kane, R. L. and Abrass, I. B.: Urinary incontinence in elderly nursing home patients. J.A.M.A, 248: 1194, 1982. 3. Ouslander, J. G. and Uman, G. W.: Urinary incontinence: opportunities for research, education, and improvements in medical care in the nursing home setting. In: The Teaching Nursing Home-A New Approach to Geriatric Research, Education, and Clinical Care. Edited by E. L. Schneider. New York: Raven Press, part IV, p. 173, 1985. 4. Kunin, C. M.: The incontinent patient and the catheter. J. Amer. Geriatr. Soc., 31: 259, 1983. 5. Starter, P. and Libow, L. S.: Obscuring urinary incontinence: diapering of the elderly. J. Amer. Geriatr. Soc., 33: 842, 1985. 6. Ribeiro, B. J. and Smith, S. R.: Evaluation of urinary catheterization and urinary incontinence in a general nursing home population. J. Amer. Geriatr. Soc., 33: 479, 1985. 7. Ouslander, J. G. and Fowler, E.: Management of urinary incontinence in Veterans Administration nursing homes. J. Amer. Geriatr. Soc., 33: 33, 1985. 8. Warren, J. W., Muncie, H. L., Jr., Bergquist, E. J. and Hoopes, J. M.: Sequelae and management of urinary infection in the patient requiring chronic catheterization. J. Urol., 125: 1, 1981. 9. Kunin, C. M.: Genitourinary infections in the patient at risk: extrinsic risk factors. Amer. J. Med., suppl. 5A, 76: 131, 1984. 10. Gleckman, R. A.: The chronically catheterized elderly patient. A selective review. J. Amer. Geriatr. Soc., 33: 489, 1985. 11. Warren, J. W., Tenney, J. H., Hoopes, J.M., Muncie, H. L. and Anthony, W. C.: A prospective microbiologic study ofbacteriuria in patients with chronic indwelling urethral catheters. J. Infect. Dis., 146: 719, 1982. 12. Breitenbucher, R. B.: Bacterial changes in the urine samples of patients with long-term indwelling catheters. Arch. Intern. Med., 144: 1585, 1984. 13. Ouslander, J. G. and Kane, R. L.: The costs of urinary incontinence in nursing homes. Med. Care, 22: 69, 1984. 14. Wieland, D., Rubenstein, L. Z., Ouslander, J. G. and Martin, S. E.: Organizing an academic nursing home. Impacts on institutionalized elderly. J.A.M.A., 255: 2622, 1986. 15. Garibaldi, R. A., Brodine, S. and Matsumiya, S.: Infections among patients in nursing homes: policies, prevalence, problems. New Engl. J. Med., 305: 731, 1981. 16. Setia, U., Serventi, I. and Lorenz, P.: Nosocomial infections among patients in a long-term care facility: spectrum, prevalence, and risk factors. Amer. J. Infect. Control, 13: 57, 1985. 17. Finnegan, T. P., Austin, T. W. and Cape, R. D. T.: A 12-month fever surveillance study in a Veterans' long-stay institution. J. Amer. Geriatr. Soc., 33: 590, 1985. 18. Farber, B. F., Brennen, C., Puntereri, A. J. and Brody, J. P.: A prospective study of nosocomial infections in a chronic care facility. J. Amer. Geriatr. Soc., 32: 499, 1984. 19. Gambert, S. R., Duthie, E. H., Jr., Priefer, B. and Rabinovitch, R. A.: Bacterial infections in a hospital-based skilled nursing facility. J. Chron. Dis., 35: 781, 1982. 20. Franson, T. R., Duthie, E. H., Jr., Cooper, J.E., Van Oudenhoven,

COMPLICATIONS OF CHRONIC INDWELLING URINARY CATHETERS

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