Catheter-Associated Urinary Tract Infection in Neurological Intensive Care Units: A Narrative Review

Abstract

Catheter-associated urinary tract infection (CAUTI) is among the most common types of healthcare-associated infection (HAI), which is associated with poor outcomes and prolonged hospitalization in critically ill patients. Previous studies have mentioned that patients admitted to neurological ICUs are at higher risk of CAUTI compared to patients in other ICU settings. This review paper aims to review studies published during the last decade that evaluated the incidence, risk factors, causative pathogens, and preventive strategies and treatment in neuro-critically ill patients.

Introduction

Urinary tract infection (UTI) is among the most common types of healthcare-associated infections (HAIs), especially in critically ill patients. ¹ It is estimated that between 70% and 80% of UTIs that occur during hospitalization are associated with a urinary catheter. ² According to the National Healthcare Safety Network (NHSN) report in 2011, pooled mean urinary catheter utilization ratios in adult critical care units ranged from .45 to .79 urinary catheter days/patient days. ³ Catheter-associated urinary tract infection (CAUTI) is associated with poor outcomes, prolonged hospitalization, and increased healthcare costs in critically ill patients. ⁴ Moreover, the rate of multidrug resistance (MDR) might be as high as 33% in this group of patients. ¹ Many patients admitted to neurologic intensive care units (neuro ICUs) receive an indwelling urinary catheter for extended periods due to urinary retention or to monitor urinary output. Therefore, neuro-critically ill patients might be at high risk of CAUTI. ⁵ According to the NHSN report in 2013, the highest rates of CAUTI were observed in neurosurgical (5.3 per 1000 catheter days), burn (4.8 per 1000 catheter days), and neurologic (4.5 per 1000 catheter days) ICUs. ⁶ While the rate of CAUTI in medical/surgical ICUs in teaching hospitals was 2.7 per 1000 catheter days, and in nonteaching locations was between 1.3 and 1.7 per 1000 catheter days. ⁶ In this paper, we aim to review studies published during the last decade that evaluated the incidence, risk factors, causative pathogens, and preventive strategies and treatment in neuro-critically ill patients.

CAUTI Definition

The 2009 Infectious Diseases Society of America (IDSA) guidelines define CAUTI in a catheterized patient or within 48 hours following the removal of the urinary catheter who meet the criteria for symptomatic bacteriuria. ⁷

Symptomatic bacteriuria is defined as the presence of symptoms or signs compatible with urinary tract infection (UTI) along with cultural growth of ≥10³ colony-forming units CFU/mL of one or more species of microorganisms. Clinical findings can be specific to the urinary tract such as flank pain, costovertebral angle tenderness, suprapubic pain or tenderness, and pelvic discomfort. Alternatively, clinical symptoms can be general, including fever, leukocytosis, hypotension, metabolic acidosis, altered mental status or malaise that are otherwise unexplained.

Asymptomatic bacteriuria (ASB) is defined as the absence of symptoms or signs consistent with UTI in a patient with cultural growth of ≥10⁵ CFU/mL of uropathogenic bacteria. ASB treatment with antimicrobials has been recognized as an important contributor to inappropriate antimicrobial use, which has increased the likelihood of antimicrobial resistance. Therefore, the higher threshold of bacterial growth in asymptomatic patients is utilized to reduce the overuse of antimicrobials, even in the presence of bacteriuria. ⁸

CAUTI Epidemiology

In the NHSN report summary of 2013, rates of CAUTIs in neurologic and neurosurgical ICUs were 4.5 and 5.3 infections per 1000 catheter days. ⁶ Compared to NHSN records from healthcare facilities in the United States, higher rates of CAUTI were reported in International Nosocomial Infection Control Consortium (INICC) reports.^9-11 The rate of CAUTI in neurologic and neurosurgical ICUs in INICC reports from 50 countries between 2010 and 2015 was 17.2 and 6.2 infections per 1000 catheter days. ⁹ CAUTI rates in neurologic and neurosurgical ICUs through INICC reports from 45 countries between 2012 and 2017 was 6.0 and 4.6 infections per 1000 catheter days, ¹⁰ and in the latest summary from 2013 to 2018 was 4.7 and 4.6 infections per 1000 catheter days. ¹¹

As is evident in Table 1, studies with higher rates of device utilization ratio (DUR) have reported higher rates of CAUTI. Notably, a very dramatic increase in CAUTI rate might be seen when DUR exceeds .85 compared to DUR <.5.^10,12-14Judicious urinary catheter use is the most important strategy to control the CAUTI rate. ⁷ According to findings from epidemiologic studies, the rate of CAUTI and DUR in neuro ICU cases has decreased during the past decade (Table 1).

Table 1.

Rate of Catheter-Associated Urinary Tract Infection and Device Utilization Ratio in Neuro ICU Patients in Different Epidemiological Studies.

First Author, YOP	Study Period	Country	Neuro ICU Cases	Patient Days	Urinary Catheter Days	CAUTI Patients	Infection/1000 Catheter Days	DUR
Rosenthal,	2013–	INICC	Neurologic:	88,772	36,043	171	4.74	.41
2021 11	2018	report of	13,989	107,282	62,131	284	4.57	.58
		45	Neurosurgical:
		countries	10,603
Rosenthal,	2012–	INICC	Neurologic:	12,925	9395	56	6.0	.73
2020 10	2017	report of	1901	89,881	73,508	337	4.6	.82
		45	Neurosurgical:
		countries	15,949
Rosenthal,	2010–	INICC	Neurologic:	18,012	16,653	286	17.17	.92
2016 9	2015	report of	2072	88,374	68,657	428	6.23	.78
		50	Neurosurgical:
		countries	15,270
Mehta, 2016 15	2004–	India	Neurologic:	12,025	8081	29	3.59	.67
	2013	(INICC)	3000	8536	5946	25	4.20	.70
			Neurosurgical:
			1947
Leblebicioglu,	2003–	Turkey	Neurologic:	30,966	29,856	596	20.0	.96
2014 12	2012	(INICC)	3784	39719	36,688	347	9.5	.92
			Neurosurgical:
			5691
Dudeck,	2013	United	Neurologic	169,140	117,424	530	4.5	.69
2015 6		States	Neurosurgical	724,923	470,403	2482	5.3	.65
		(NHSN)
Dudeck,	2012	United	Neurologic	157,449	118,556	441	3.7	.75
2013 16		States	Neurosurgical	713,836	489,391	2464	5.0	.69
		(NHSN)
Dudeck,	2011	United	Neurologic	48,549	34,422	116	3.4	.71
2013 3		States	Neurosurgical	261,682	181,986	812	4.5	.70
		(NHSN)
Dudeck,	2010	United	Neurologic	33,829	27,681	84	3.0	.82
2011 5		States	Neurosurgical	150,613	110,797	446	4.0	.74
		(NHSN)
Perrin, 2021 14	2016–	United	3045	2016:	3770	21	5.34	.39
	2018	States		9729	3155	17	5.69	.33
				2017:	3089	7	2.20	0.4
				9710
				2018:
				7834
Abulhasan,	2015–	Kuwait	913	2015:	1420	13	9.2	.94
2020 13	2017			1514	1376	13	9.4	.94
				2016:	1789	14	7.8	.95
				1461	4585	40	8.7	.95
				2017:
				1874
				Total:
				4849
Podkovik	2018–	United	146	NA	1189	0	0	NA
2019 17	2019	States
Abulhasan,	2010–	Canada	6033	20,800	14,557	NA	4.9	.71
2018 18	2016
Hagerty,	2005–	United	242 (SAH)	NA	NA	54	20.7	NA
2015 19	2012	States

CAUTI: catheter-associated urinary tract infection, DUR: device utilization ratio, INICC: International Nosocomial Infection Control Consortium, NA: not available, NHSN: National Health Safety Network, YOP: year of publication.

Higher rates of CAUTIs in INICC reports might be due to the participation of resource-limited countries. Lack of organized infection control guidelines, low nurse-to-patient ratios, overcrowded public hospitals, lack of medical supplies or outdated technology, and an insufficient number of trained healthcare workers are among the most important reasons for higher rates of CAUTIs in these countries.^12,13

CAUTI Diagnosis

Diagnosis of UTI in neurocritical patients can be challenging as patients frequently develop systemic inflammation related to their primary neurological disturbance. ²⁰ Therefore, the appropriate diagnosis of CAUTI is the mainstay of effective and timely interventions, including proper treatments. ²¹ Many guidelines have been developed and introduced for the diagnosis of CAUTI in patients receiving treatment in ICU ²² ; however, evidence on the diagnostic criteria for neuro ICU patients seem not to be that much abundant. An effort to provide an evidence-based protocol in this regard, proposed a diagnostic criteria for CAUTI in neuro ICU patients defined as patients having urethral, suprapubic, or intermittent urinary catheter with UTI signs and symptoms and ≥10³ colony-forming units (CFU)/mL of ≥1 bacterial pathogens cultured from a single catheter urine sample or a midstream sample while the patient did not have any urinary catheter or condom catheter in previous 48 hours and any other source of infection has been excluded. ²¹ Therefore, clinicians need to explore extra information out of patients’ signs and symptoms to appropriately diagnose the CAUTI, besides the routine symptoms generally associated with this condition. Neuro-specific signs and symptoms like increased bladder spasticity, autonomic dysreflexia, and sense of unease in urination in patients with spinal cord injury are compatible with CAUTI diagnosis in these patients.^7,21 We found no further evidence on these specific symptoms on neurologic diseases and injuries in the literature based on our updated search in this review. Altogether, it is important to keep in mind that diagnosis with the help of lab tests is accurate, but the essential basic component is to avoid overdiagnosis and the following overtreatment in the path of saving patients against inpatient complications. ¹⁷ Additional data of literature on the diagnosis of CAUTI in neuro ICU is available in Table 2.

Table 2.

Diagnostic Criteria for CAUTI in Neuro ICU Patients in the Literature.

First Author, YOP, Country	Main Criterion	Signs and Symptoms	Not Diagnostic Criteria
Dayts 2014 (evidence-based protocol), 21 USA	In patients with indwelling urethral, indwelling suprapubic, or intermittent catheterization with presence of symptoms or signs compatible with UTI with no other identified source of infection along with ≥103 colony-forming units (CFU)/mL of ≥1 bacterial species in a single catheter urine specimen or in a midstream voided urine specimen from a patient whose urethral, suprapubic, or condom catheter has been removed within the previous 48 hours	• New-onset or worsening of fever (>38°C) • Rigors and altered mental status • Malaise, or lethargy with no other identified cause • Flank pain • Costovertebral angle tenderness • Acute hematuria • Pelvic discomfort; and, in those whose catheters have been removed, dysuria, urgent or frequent urination, or suprapubic pain or tenderness	• Pyuriaabsence of odorous or cloudy urine alone
Hagerty 2015 (based on CDC 2009 guideline), 19 USA	In patients with urinary catheters in place for >48 hours by the presence of at least one sign/symptom and at least one positive urine culture growing 9 105 CFUs/mL with no more than two microorganisms	• Temperature >38°C • Urinary frequency • Urgency • Dysuria • (e) Suprapubic tenderness/pain
Podkovik 2019, 17 USA	We recommend a diagnosis of UTI in a febrile patient with an indwelling catheter for at least five days when other diagnoses such as pneumonia, line infection, venous thrombi, or medication reactions have been ruled out through the appropriate tests
Abulhasan 2020, 13 Kuwait	An ICU acquired HAI was defined as an infection arising ≥48 h after admission to the ICU that was neither present nor incubated on ICU admission
Perrin 2020, 14 USA	CAUTI was defined as a quantitative culture containing ≥105 colony-forming units (CFU)/mL of one or two microorganisms in a patient with an indwelling urinary catheter in place for more than 2 consecutive days	With one of these four signs or symptoms: • Fever (>38.0°C) • Suprapubic tenderness • (3) Costovertebral angle pain • (4) Costovertebral angle tenderness
CDC 2021, 22 USA	Patient had an indwelling urinary catheter that had been in place for more than 2 consecutive days in an inpatient location on the date of event AND was either: • Present for any portion of the calendar day on the date of event, OR • Removed the day before the date of event AND patient has a urine culture with no more than two species of organisms identified, at least one of which is a bacterium of ≥105 CFU/ml	Patient has at least one of the following signs or symptoms: • Fever (>38.0°C) • Suprapubic tenderness • Costovertebral angle pain or tenderness • Urinary urgency • Urinary frequency • Dysuria

CAUTI Risk Factors

Duration of urinary catheterization is the most important risk factor for CAUTI.^19,23 The presence of a urinary catheter may damage the bladder mucosa, impair the defense mechanisms, and provide a route of entry for bacteria. ² The risk of developing bacteriuria, which is the precursor of CAUTI, is about 3% to 10% per day of catheterization.^7,24 In a study conducted on neuro ICU patients, the average time from urinary catheterization to acquiring the CAUTI was 6.2 days, and the majority of patients developed CAUTI within 10 days. ¹⁴

Female gender, increased age, diabetes mellitus, and extended length of hospital and ICU stay are other well-established risk factors for CAUTI in hospitalized patients. ²⁵ Few studies have evaluated risk factors for CAUTI in neuro ICU patients.^14,19,20 In a retrospective cohort study conducted on SAH patients, diabetes mellitus was the only significant independent risk factor for CAUTI. ²⁰ In another retrospective study, hyperglycemia (odds ratio: 13.0, 95% confidence interval: 1.28–107.4), older age (odds ratio: 1.06, 95% confidence interval: 1.01–1.11), and anemia requiring transfusion (odds ratio: 3.78, 95% confidence interval: .98–14.67) were found to be significant predictors of CAUTI in patients with SAH. ¹⁹ Impaired immune function, increased adherence of uropathogens to urothelium, and enhanced growth of uropathogens secondary to glucosuria make diabetic patients more susceptible to CAUTI. ²⁶

In a recent study published by Perrin et al., ¹⁴ risk factors for CAUTI were evaluated in 3045 patients admitted to a neuro ICU of a single tertiary teaching hospital in the United States. In the univariate analysis, age between 61 and 80 years, female gender, hospital length of stay more than 22 days, neuro ICU length of stay more than 10 days, SAH primary diagnosis, and HTN were associated with CAUTI. ¹⁴ However, in the multivariate analysis, age between 61 and 80 years, female gender, neuro ICU length of stay more than 10 days, and stool incontinence were independent risk factors for CAUTI. ¹⁴

Neurogenic bladder and other neurological causes of urinary retention such as stroke and multiple sclerosis might also increase the risk of CAUTI. ²⁷ UTIs are one of the many complications that can be seen in a neurologically injured patient that suffers from the neurogenic bladder. ²⁸ Neurogenic bladder can be caused by acquired brain injury, nerve damage, or patients that have a spinal cord injury. ²⁸ Neurogenic bladder is defined as a condition where a patient is unable to control normal bladder function (urination, urine storage, etc.,) due to damage to the brain, spinal cord, or nerves. ²⁹ Research from the United States reports the frequency of neurogenic bladder to be 40–90% in multiple sclerosis, 40–61% in spina bifida, and 70–84% in spinal cord injury.^30,31 Individuals with reversible spinal disorders (e.g., disc herniation or compression) may regain their bladder function after correcting the spinal lesion, contrary to patients with progressive or permanent neurologic diseases. ³² Therefore, the risk of UTI in patients with permanent insult might be higher than those with reversible spinal damage. In patients with a spinal cord injury, UTI accounts for more than 1/5 of hospitalizations. ³³ In most cases, patients who have neurogenic bladder due to a neurological injury likely will suffer from a UTI. According to statistics, UTIs occur 2.5 episodes per patient per year in patients that have neurogenic bladder. ³³ It is estimated that over one-third (36.4%) of patients will be diagnosed with a UTI at least one year after the neurogenic bladder has been diagnosed. ²⁹

There are multiple unique risk factors that predispose patients and must be considered in the pathogenesis of UTIs in the setting of a neurogenic bladder. ³³ One must consider the bacteria that are uropathogenic, that now obtain the ability to adhere to the cells walls of the bladder and internalized by the urothelium cells. ³⁴ The urothelium cell wall has glycosaminoglycan (CAG) layer that prevents uropathogenic bacteria from invading the cell wall. ³⁴ The local inflammatory response that is elicited from initial bacterial pathogens binding to the bladder cell wall will cause damage and disruption to the cell wall layer, making the wall susceptible to bacterial invasion and infection. ³⁴ In addition, patients with a neurogenic bladder lose the ability to regularly void urine. The normal physiological void serves the purpose of preventing uropathogenic bacteria from growing within the urine and binding to urothelium cells, and it prevents the bladder from over distending. ³⁴ Bladder distension creates high pressure within the bladder wall, decreasing blood flow within the blood vessels of the bladder creating bladder ischemia. ³⁴ Bladder ischemia, caused by bladder overdistension and high intravesical pressure, will cause decreased blood flow to the bladder tissue, decreasing the number of inflammatory cells and antibiotics to the site of infection. ²⁹ Innate immunity is also altered in neurogenic bladder patients. Immunoglobulin A (IgA) plays a key role in preventing bacteria from binding the urothelium cell wall. ³⁵ Studies have shown a decreased amount of IgA in neurogenic bladder patients when compared to non-neurogenic bladder patients, making these patients more vulnerable to infections. ³⁵

CAUTI Pathogens

Pathogen patterns responsible for CAUTI in the Neurological ICU are similar to other hospital settings. The pathogenic biofilm causing the CAUTI could be colonized on the inner (intraluminal infection) or outer (extraluminal infection) surfaces of a catheter.^2,36 This biofilm is mainly composed of pathogenic bacteria with different reported shares of various bacteria; however, fungal infections like candida have also been reported causing CAUTI. ³⁶ Among the surveys, the most prominent pathogen has been found to be Escherichia coli (E. coli). Gram-negative rods are the most common type of pathogen isolated, with other bacterium and candida being less common. Previous studies have shown that patients are usually affected with more than one pathogen, and total isolated microorganisms exceed the number of infected cases. Additional data on the distribution of various pathogens responsible for CAUTI in these patients is available in Table 3.

Table 3.

Pathogens Responsible for CAUTI in Neuro ICU Patients in Literature.

First Author, YOP, Country	Number of CAUTI Cases	Total Isolates	Pathogens (%)
Perrin 2020, 14 USA	45	45	E. coli: 23 (51.11%)
			P. aeruginosa: 5 (11.11%)
			E. aerogenes: 2 (4.44%)
			Others: 15 (33.33%)
Abulhasan 2018, 18 Canada	78	87	E. coli: 39 (44.8%)
			Enterococcus: 14 (16.1%)
			Other enterobacteriaceae: 11 (12.6%)
			Pseudomonus spp: 7 (8.0%)
			Klebsiella spp: 5 (5.7%)
			Other Gram positives: 5 (5.7%)
			S aureus: 3 (3.4%)
			Candida: 2 (2.3%)
			Other Gram negatives: 1 (1.1%)
Abulhasan 2018, 20 Canada	36	90	Escherichia coli: 41.5%
			Others: Not mentioned
Abulhasan 2020, 13 Kuwait	40	52	Klebsiella species: 16 (30.8%)
			Escherichia coli: 13 (25.0%)
			Pseudomonas aeruginosa: 7 (13.5%)
			Enterococcus faecalis: 7 (13.5%)
			Staphylococcus hemolyticus: 2 (3.8%)
			Candida spp.: 2 (3.8%)
			Enterobacter: 1 (1.9%)
			Staphylococcus aureus: 1 (1.9%)
			MRSA: 1 (1.9%)
			Serratia marcescens: 1 (1.9%)
			Other enterobacteriaceae: 1 (1.9%)
Dayts 2014, 21 USA	40	44	Escherichia coli: 11 (25%)
			Klebsiella pneumonia: 9 (20.5%)
			Enterococcus faecalis: 7 (15.9%)
			Pseudomonas aeruginosa: 4 (9.1%)
			Enterobacter cloacae: 2 (4.5%)
			Enterococcus faecium: 1 (2.3%)
			Escherichia coli ESBL: 1 (2.3%)
			Citrobacter werkmanii: 1 (2.3%)
			Proteus mirabilis: 1 (2.3%)
			Streptococcus agalactiae: 1 (2.3%)
Menon 2020, 37 India	248	227	Escherichia coli: 63 (27.75%)
			Klebsiella species: 41 (18.06%)
			Candida species: 39 (17.18%)
			Enterococcus species: 27 (11.89%)
			Pseudomonas species: 18 (7.9%)
			Enterobacter species: 16 (7.04%)
			Acinetobacter species: 5 (2.2%)
			Miscellaneous organisms: 18 (7.9%)
Djordjevic 2012, 38 Serbia	74	127	Enterobacter cloacae: 25 (19.69%)
			Klebsiella spp: 20 (15.75%)
			Proteus mirabilis: 16 (12.60%)
			Pseudomonas aeruginosa: 14 (11.02%)
			Escherichia coli: 13 (10.24%)
			Klebsiella oxytoca: 12 (9.45%)
			Acinetobacter spp: 4 (3.15%)
			Proteus vulgaris: 3 (2.36%)
			Klebsiella pneumonia: 2 (1.57%)
			Other gram negative: 5 (3.94%)
			Staphylococcus aureus: 6 (4.72%)
			Coagulase-negative Staphylococci: 4
			(3.15%)
			Enterococcus faecalis: 3 (2.36%)
Jaradat 2019, 39 Jordan	52	62	Escherichia coli: 17 (27.4%)
			Enterococcus species: 8 (12.9%)
			Acinetobacter baumannii: 7 (11.3%)
			Morganella morganii: 3 (4.8%)
			Pseudomonas aeruginosa: 4 (6.5%)
			Klebsiella pneumonia: 11 (17.7%)
			Enterobacter cloacae:1 (1.6%)
			Candida: 11 (17.7%)
Titsworth 2012, 40 USA	—	—	Escherichia coli: 33%
			Klebsiella: 12%
			Candida: 11%
			Pseudomonas: 11%
			Enterococcus: 10%
			Proteus: 6%
			Enterobacter: 5%
			Citrobacter: 2%
			Serratia: 2%

CAUTI Treatment

Treatment of neurocritical patients afflicted with CAUTI includes catheter management and antimicrobial therapy. ⁷ Catheter utilization should be minimized and ceased as soon as possible in patients whose management is possible without inserting a urinary catheter. In patients who still require a catheter, intermittent catheterization with the goal of reducing microorganism colonization is suggested. ²¹ A previous guideline proposed an evidence-based treatment algorithm for neuro ICU patients with CAUTI. According to the mentioned guideline, patient management starts with a urine sample for culture before beginning any antibiotics from a freshly placed catheter or a voided midstream sample. The antimicrobial treatment starts with an empirical prescription based on the specific neuro ICU antibiogram, and the regimen changes immediately after the preparation of pathogen culture and antibiotic sensitivity analysis. Treatment duration is 7 days for patients with prompt resolution of symptoms, and 10–14 days for those with a delayed response. ²¹ Details of this guideline are summarized in Table 4. Oral or parenteral administration of antibiotics depends on the patient’s status; however, for patients who can take the drugs orally and the oral antibiotic is effective against the detected pathogens, it is suggested to prescribe oral medication instead of parenteral antibiotics. ² One of the important factors for a more effective treatment is considering microorganism resistance to antibiotics and choosing the more effective agent to treat the CAUTI. ⁴¹

Table 4.

Concise Review of the Proposed Guideline on the Treatment of CAUTI in Neuro ICU Patients.

First Author, YOP, Country	Primary Management	Empirical Treatment	Antibiotic Therapy Duration
Dayts 2014,21 USA	• A urine specimen for culture should be obtained prior to initiating antimicrobial therapy in view of the wide spectrum of infecting organisms and the likelihood of antimicrobial resistance • Replace catheter if it was in place for more than 2 weeks in case of continuation of catheterization	It should be selected according to an NCU antibiogram and tailored to an organism’s culture and sensitivity results as soon as the data are available	• Patients with immediate response to antibiotic treatment: 7-day regimen • Patients with delayed response to antibiotic treatment: 10–14 days regimen • Patients with CA-UTI who are not severely ill: 5-day regimen of levofloxacin • Women ages ≤65 years who develop CA-UTI without upper urinary tract symptoms after an indwelling catheter has been removed: 3-day regimen
Hooton 2009,7 USA	• Before any antibiotic treatment begins, it is important to remove any indwelling catheter and, if necessary, place a new catheter.	If antimicrobial therapy must be started empirically, review the patient’s previous urine cultures, the local antibiogram, and/or the clinical practice guidelines to choose an appropriate treatment.	• There is no clear optimal duration of antimicrobial therapy for CAUTIs; however, most patients respond to a relatively short course of treatment (≤7 days). • In patients who respond slowly to therapy, 10–14 days may be required

CAUTI and Outcomes

Previous studies have shown that CAUT is associated with adverse outcomes in neuro ICU patients.^{4,18,20,39,41} Prolonged length of ICU stay is a well-known early complication of CAUTI in critically ill patients.^{4,18,20,39,41} It is estimated that the occurrence of CAUTI may increase the length of ICU stay by 8–11 days and hospital length of stay by 7–20 days. ¹⁸ HAIs, including CAUTI, may also increase the rate of readmissions. ⁴² One study conducted on patients with aneurysmal SAH showed that 3.5% of hospital readmissions within the first 30 days after discharge were due to UTIs. ⁴²

Contradictory results were reported regarding the impact of CAUTI on the survival of neuro-critically ill patients. ⁴³ While some studies reported an increased in-hospital mortality rate among patients with CAUTI, ⁴⁴ the others did not show any significant effect of CAUTI on patients’ survival.^18,41,43 Surprisingly, one study reported an improved survival rate after adjusting for known confounders in patients with moderate to severe traumatic brain injury (TBI). ⁴⁵ Due to the small sample size and retrospective design of these studies, further multi-center prospective studies are needed to address the impact of CAUTI in neuro-critically ill patients.

CAUTI Preventive Strategies

Infection prevention and control (IPC) programs have been shown to be an effective strategy to decrease the incidence of HAIs, including CAUTI. To prevent HAIs, the WHO recommends implementing an IPC program in every acute healthcare facility. ⁴⁶ Many prospective studies have evaluated the impact of a range of interventions to reduce the rate of CAUTI in critically ill patients. ⁴⁷ The basic principles of CAUTI prevention are restricting the use of indwelling urinary catheters, adequate staff expertise and using aseptic procedures during catheter insertion, maintenance of catheter sterility, continuously closed drainage system, surveillance of the necessity of catheterization, and early removal of catheter. ⁷ Some prospective studies have implemented similar strategies in neuro ICU patients (Table 5).^40,48-52 The result of these studies showed that by educating neuro ICU staff and defining proper institutional prevention protocols, a significant reduction in CAUTI rates could be achieved.^40,48-52 The following algorithm summarizes best practices for the prevention of CAUTI in neuro ICU patients which is created by the corresponding author’s institution at University Health System Hospital of San Antonio, Texas, Figure 1. Protocol recommendations may not always be applicable in all clinical settings. Therefore, it is necessary for clinicians to use their professional judgment and consider the patient’s circumstances, as well as the available resources, when making decisions.

Table 5.

Summary of studies that evaluated bundle interventions for CAUTI prevention.

First author, YOP, Country	Neuro ICU cases	Key elements	CAUTI rate		Significant
			Before	After
Soundaram, 2020, India 48	Pre- implementation: 269 Post- implementation: 257	• Proper indication documented • Closed drainage system • Urinary catheter secured/not obstructed • Drainage bag above the floor and below bladder level • Hand hygiene • Vaginal/meatal care • Perineal care • Single-use glove while handling/emptying • No contact b/t jug and bag • Separate jug for collecting • Assessment of readiness to remove—documented?	14.6	5.7	Yes
Ershova, 2018, Russia 49	2011: 313 2012: 350 2013: 361 2014: 341 2015: 326 2016: 347 Total: 2038	• Adopted from the 2007 CDC guideline • Minimization of device disconnecting • Sterile device implantation according to the protocol and only by clear indications • Removing as soon as possible	NA	16.6 22.3 16.4 15.7 14.4 12.4 16.0	No
Mullin, 2017, United States 50	2013 a : 11,117 2014 a : 11,589	• Assessment of competency with catheter insertion and maintenance • Maintaining a closed system • Initiation of a nursing driven protocol for catheter removal • Improved fidelity of electronic documentation of catheters • Implementation of preservative tubes for specimen collection • Periodic maintenance audits of catheters	Q1: 8.4 Q2: 8.5 Q3: 3.9 Q4: 1.9 Mean: 5.7	5.4 1.7 0 2.7 Mean: 2.5	Yes
Schelling, 2015, United States 51	NA	• Daily assessments of indwelling urinary catheter necessity and possibility of removal • Hand hygiene and glove changing • Maintenance of a closed system • Considering alternatives to IUC • Bowel management program	8.18	.93	Yes
Cheng, 2014, Taiwan 52	NA	• Hand hygiene • Clear indications for urinary catheter insertion • Use of aseptic technique by trained healthcare providers • Maintenance of a sterile closed drainage system • Keeping the drainage bag below the level of the bladder • Daily review of indications for the urinary catheter • Early removal of unnecessary catheters • Avoiding routine changing of catheters or drainage bags	3.86 (Jan–June 2012)	3.68 (July–Dec 2012) 2.61 (Jan–June 2013) 0 (July 2013– Dec 2013)	Yes
Titsworth, 2012, United States 40	NA	• Avoidance of catheter insertion • Maintenance of sterility • Product standardization • Early catheter removal	13.3	4.0	Yes

^aAll ICU cases.

Figure 1.

Indwelling urinary catheter removal algorithm.

Prevention of UTIs within a neurogenic bladder has changed over the years. The use of prophylactic antibiotics to prevent UTIs is not supported due to the increasing resistance to antibiotics. ⁵³ In the rehabilitation setting, use of foley or suprapubic catheter, and the practice of intermittent catheterization is the preferred method to prevent UTI in patients with neurogenic bladder. ²⁹ The use of intermittent self-catheterization and suprapubic catheter is associated with fewer UTIs. ⁵⁴ Recent studies have shown that UTIs correlated with multidrug-resistant bacteria is more associated with patients who use indwelling catheterization (2.6%) vs patients who practice self-catheterization (.7%). ⁵⁵ With that being said, one must understand that the use of foley catheters for neurogenic bladder, may be necessary in the clinical setting and vary case by case. For example, patients who do not have good family support or may have limited hand function may benefit from a foley catheterization rather than intermittent catherization. ⁵⁶ Foley catheter insertion also may prevent spinal cord injury complications such as bladder distention, hydronephrosis, renal damage, etc., ⁵⁶

Conclusions

CAUTIs are one of the most common types of HAI in neuro ICU patients, leading to increased morbidity, patient costs, and length of hospitalization. The duration of catheterization is the most significant risk factor, especially among neuro-critically ill patients with indwelling urethral, suprapubic, or intermittent catheterization. Based on many reports, antibiotics have not only failed to reduce infection rates in patients with prolonged catheterization but have also led to antibiotic-resistant organisms. CAUTIs can be avoided by using catheters only when they are truly necessary and removing them when no longer clinically indicated. It is also important to use proper catheter insertion and maintenance techniques in order to reduce the CAUTI rate. ³⁶

Studies found that Gram-negative bacilli were the most frequently isolated bacterial pathogens in positive urine cultures acquired in intensive care units, with E.coli, the most common isolate and that other bacteria and candida are less common. ³⁸

A selection of antimicrobial should be based on culture results when available due to the wide range of potential pathogens and the increased likelihood of antimicrobial resistance. Despite this, prompt treatment is warranted in certain cases, even before the availability of culture data. Most patients need 7–14 days of treatment, depending on their clinical response, the organism infected, and the medication used. It is recommended that patients with spinal cord injury receive CA-UTI treatment for 14 days, resulting in better clinical and microbiological outcomes than short-course therapy. ²¹

There is a limitation of being unable to use the IDSA definition of CAUTI in neurocritical care patients, leading to the possibility of misdiagnosis of CAUTI in these patients. The second limitation is that there may not be enough studies to evaluate the rate of CAUTI and DUR in neuro ICU patients or compare it with other ICU facilities. The third limitation is the small sample size of reviewed studies, which may not sufficiently represent an entire neuro ICU patient population. Therefore, further studies on neuro ICU patients with different diagnostic groups and larger sample sizes are needed to address these limitations. One qualitative study had demonstrated that “difficulty with nurse and physician engagement,” “patient and family request for indwelling catheters,” and “catheter insertion practices and customs in the emergency department” are major barriers to reducing urinary catheter use. ⁵⁷ The authors suggested that incorporating urinary management among other patient safety programs, debating the risks of indwelling urinary catheters with patients and caregivers, and engaging with emergency department staff to implement strategies that ensure appropriate catheter use might address these obstacles. ⁵⁷

We suggest that neuro ICU patients receive additional attention because CAUTI in those might be associated with poor outcomes. Using evidence-based strategies such as insertion bundles and training staff to be asepsis-aware during maintenance of catheters have reduced the ratio of catheter utilization and incidence of CAUTI and related complications in neuro ICU patients. ²¹ In some cases, these recommendations may not be appropriate for all clinical circumstances; therefore, clinician decisions must be based on professional judgment, consideration of patient circumstances, and availability of resources.

ORCID iD

Ali Seifi https://orcid.org/0000-0002-5010-5041