1 | P a g e

Systematic Review on effectiveness and cost effectiveness of ultrasound bladder scanner for

postvoidal measurement in reducing unnecessary catheterization and the risk of urinary tract

infection associated with catheterization

Attia, D 1, Hiligsmann, M.1, Hellinckx, H3, Wijnen, B.F.M1 , Evers, S.M.A.A.1, 2

1 Department of Health Services Research, CAPHRI School for Public Health and Primary Care,

Maastricht University, Maastricht, The Netherlands

2 Trimbos Institute, National Institute of Mental Health and Addiction, Utrecht, The Netherlands

3 Health Economics and Outomes Research (HEOR) beMedTech, Belgium

Dalia Attia

Student ID I6106301

1st academic supervisor: Silvia Evers

2nd academic supervisor: Mickaël Hiligsmann

Institutional supervisor at BeMedTech, Belgium: Hans Hellinckx

MSc Healthcare Policy, Innovation and Management

Faculty of Health, Medicine and Life science

Maastricht University

Year 2016

Journal: Clinical Nursing Journal

Article Words: 4965 without tables and appendixes

(Submissions should not exceed 8,000 words, excluding abstract, tables, figures, and reference

list.as per criteria for review articles on clinical nursing journal. And not less than 3000 words)

Abstract: 294

(Should not exceed 300 words)

40 pages

2 | P a g e

ABSTRACT

Background: Ultrasound bladder technology has been adapted as a bladder assessment tool

of urine retention and to measure Postvoid residual urine volume instead of intermediate

catheterization. Due to the significance of bladder ultrasound in reducing undesirable

complications of catheterization, this review aims to examine (up-to-date) evidence on

effectiveness and cost-effectiveness of this new technology, alongside with the methodological

quality of all recent studies.

Method: Systematic search were limited to English-language studies in humans from the

year 1985 to June 2016. The Studies documenting incontinent hospitalised patients to evaluate

bladder urinary volume in different healthcare settings, and using ultrasound bladder scanner as

an alternative to catheterization, and avoiding urinary tract infections associated with

catheterisation Any relevant experimental designs were included, as well as any partial or full

Economic Evaluation. Each article was critically appraised for quality using special tools.

Result: the review yielded 29 relevant studies with methodological quality ranging from

moderate to high. In spite of different device models; users; patient positions; or healthcare

setting, results were consistent and can be generalized revealing accuracy of bladder volume

assessment by bladder scanners. Seven studies with sufficient sample size demonstrated a

reasonable reduction in UTI rate and avoidance of unnecessary catheterization. Three of them

evaluated the cost savings partially. Nevertheless; no complete economic evaluation were found to

document the device cost-effectiveness.

Conclusion: the review evolved by providing sufficient evidence on the device accuracy to

the evaluation of clinical benefits in diagnosing retention without the use of intermittent

catheterization thus decreasing the costs associated with catheterization and reducing the risk of

urinary tract infection.

Relevance to clinical practice: ultrasound bladder should commonly be used by nurses and

specialists in peri-operative units, neurology units, obstetrics-gynecology units, long-term care,

home care and rehabilitative units, to verify retention prior to catheterization.

Keywords: Urinary retention, urinary tract infection, UTI, Ultrasound bladder, CAUTI,

nosocomial infection, Cost-effectiveness

3 | P a g e

Contents

SUMMARY ........................................................................................................................................ 1

1. INTRODUCTION ........................................................................................................................ 4

1.1 Background ............................................................................................................................ 4

1.2 New clinical guidelines and recommendations ....................................................................... 4

1.3 Aim of the study ..................................................................................................................... 5

2. METHOD ................................................................................................................................... 5

2.2 Literature Search .................................................................................................................... 6

2.3 Data Extraction....................................................................................................................... 6

2.4 Quality Assessment ................................................................................................................ 6

2.5 Evidence Synthesis ................................................................................................................. 6

3. RESULTS ................................................................................................................................... 7

3.1 Study Selection ..................................................................................................................... 7

3.2 Study characteristics ............................................................................................................. 7

3.3 Methodological quality ......................................................................................................... 17

3.4 Summary on Accuracy of Bladder Scanners Results .............................................................. 20

3.5 Summary on Health Outcomes of Bladder Ultrasound .......................................................... 26

4. DISCUSSION ............................................................................................................................ 31

5. CONCLUSION ............................................................................................................................. 32

6. RELEVANCE TO CLINICAL PRACTICE........................................................................................ 32

APPENDIX 1: List of abbreviations .......................................................................................... 33

APPENDIX 2: Search string, inclusion and exclusion criteria ................................................... 34

APPENDIX 3: EPH PP GLOBAL SCORING ................................................................................... 35

REFERENCES ........................................................................................................................... 36

4 | P a g e

1. INTRODUCTION

1.1 Background

Urinary retention (UR) is not considered a life-threatening symptom, however, it constitutes

to a long-term burden on the individual and institutional expenditures as well as negative impact

on quality of life of patients (1). UR is the inability to empty the bladder voluntarily or tolerating it

being full, and can be diagnosed as acute UR or chronic UR. UR is more common in elderly men than

women and its incidence is more frequent in the postoperative period (1, 2).

To diagnose the UR, a quantitative measure for bladder management is used to measure

Postvoid residual urine volume (PVR) as recommended by the clinical practice guidelines prepared

by the agency for health care policy and research(3). A traditional technique like catheterization is

used to measure the amount of urine in the bladder immediately after urination PVR (1, 2). Many

studies have shown that UR has been associated with poor outcomes including urinary tract

infection, bladder overdistension, urethral trauma and higher hospital mortality rates, as direct

clinical complications.

One of the main side effects of catheterization is urinary tract infections (UTIs), also called

nosocomial infection, which further increase hospital length of stay. The estimated cost of treating

a UTI ranges from $500 to $1000 per patient while the risk of developing UTI increases 3% to 6%

each day a catheter remains indwelling (4). Furthermore, results indicated a possible $3.64 cost of

each catheter tray supply and $680 cost per each UTI (5). These estimations were also emphasized

by Meddings et al. who stated that catheter-related UTI is associated with an additional cost of $676

per admission (or $2836 if further complicated by bacteraemia), when an unnecessary urinary

catheter is forgotten (6).

Although catheterization is the most common diagnostic procedure in primary healthcare to

measure urine volume, yet it has many drawbacks like being painful and uncomfortable for the

patient leading to lower patient satisfaction. Another significant problem is the high incidence of

urinary tract infection due to the passage of bacteria through a catheter into urethra causing a kind

of infection called catheter-associated urinary tract infection (CAUTI) (2).

Moreover, routine catheterization can be even more challenging for cognitive impaired

patients or physically disabled patients after hip fracture or stroke, causing a higher burden on the

nursing staff at PHC and decreased quality of life of patients and their caregivers at home (1, 2).

As an alternative technology, Mevcha & Drake stated that portable ultrasound bladder (UB)

offers a portable, non-invasive, painless method which satisfies patient's comfort and dignity

(2010). Additionally, there is an indirect benefit by safely avoiding urinary infection or urethral

trauma caused by catheterization. Lastly, direct and indirect savings in nurses' time, tools for

catheterization, laundering, and medical imaging services are being recognized to counterbalance

the costs associated with implementing PBU (2, 7).

1.2 New clinical guidelines and recommendations

In general, urinary tract infection (UTI) has long been considered the most common

healthcare-associated infection (HAI), which can be mostly preventable. UTI accounts for 40% of all

hospital-acquired infection, 32% of them are linked to CAUTI which is a life-threatening infection

(3). Given its clinical significance, many published guidelines and protocols to prevent CAUTI,

advocate for the reduction of unnecessary catheterization and removal the catheter as soon as

possible. Some of them have mentioned the use of ultrasound bladder (UB), like “Bladder Bundle”

implemented by the Michigan Health and Hospital Association (MHA) Keystone Center for Patient

Safety & Quality, and “Urinary retention protocols” also called catheter restriction protocols,

recommend the integration of portable bladder ultrasound to verify retention prior to catheterization

(6).

5 | P a g e

1.3 Aim of the study

The association between urinary catheterization and urinary tract infection is well

documented in the literature (1, 2, 5, 8). A recent meta-analysis was found to be conducted in

2010 by Palese et Al, who stated that overall evidence on using ultrasound bladder scanner

helping the reduction in risk of urinary tract infection associated with catheterization was

consistent, and concluded that UB significantly reduced the risk of CAUTI by 73%, however, lack of

assessing study quality was considered the main limitation for this study (1). Therefore, more

research for clinical and cost effective alternatives is still needed.

Previous research shows positive results regarding the effectiveness of UB and reducing

CAUTI. There is also an assumed potential of UB to be cost-effective for reducing undesirable

complications of catheterization and decreasing unnecessary catheterization. We decided to

conduct a systematic review which aims to examine (up-to-date) evidence concerning the

methodological quality of all recent studies and the effect of this quality on the interpretation of

effectiveness and cost-effectiveness results.

2. METHOD

2.1 Study PICO

Device and comparator

There are two methods for assessing PVR urine volume: sterile catheterization as a direct

method and bladder ultrasound as an indirect method.

A catheter is a soft, thin, flexible tube that is inserted through the urethra to drain urine

from the bladder. Post-void residual is the removal of urine remaining in the bladder after the

person has urinated through the placement of a catheter and functions to measure the extent of

PVR (one-time or intermittent catheterization) and to decrease the build-up of urine in the bladder

(indwelling catheterization). Catheterization, as mentioned earlier, is one main cause of bladder

infections, UI, and permanent damage to the urinary system, especially the bladder and kidneys (1,

2, 8).

Urinary bladder ultrasound products are an automated technology used as a diagnostic aid

by Healthcare professionals (primarily nurses), who administer the device to measure PVR volume

and prevent unnecessary catheterization (8).

Due to its non-invasive nature, the use of ultrasound technology may reduce the risk of

urethral trauma and urinary infection associated with catheterization. The BU is available in both

3-dimensional (3D) and 2-dimensional (2D) versions. There is also portable ultrasound machines

offer potential benefits over the stationary machines due to transferability and ease of use (9).

Population

The scanner is used, in adults and children with urinary problems, as follows:

• postoperative patients at risk of urinary retention (UR);

• patients with UTIs, urinary incontinence (UI), enlarged prostate, urethral stricture,

neurogenic bladder and other lower urinary tract dysfunctions; and

• Patients with conditions that interfere with voidings, such as spinal cord injuries,

stroke, and diabetes.

All age ranges were included in our review from newborn to geriatrics.

Outcome

To indicate effectiveness, in terms of accuracy, we reported on estimation mean difference

between control and intervention group (mL), and how significant the difference (P<0.05) was. We

also used % or number to rate the reduction in the incidence of UTI and avoidance of unnecessary

cauterization.

6 | P a g e

For the economic evaluations of UB, either full or partial, we reported on cost-benefit or cost

savings (in monetary value) and incremental cost by (number of years) or Cost-effectiveness (in

terms of incremental cost-effectiveness ratio ICER).

2.2 Literature Search

The following electronic databases were searched: Medline and NHSEED to identify all

English language studies available in print or online between January 1985 and July 2016. We have

chosen the NHS Economic Evaluation Database (NHS EED) to identify as many studies on economic

evaluations in the literature as possible (available through www.york.ac.uk/inst/crd)

The search strategy included information on the problem/population, intervention,

comparison, outcome, type of treatment, type of study (PICOTT), as medical technology is

evaluated (Schardt, 2007). Based on the last existing published meta-analysis on UB, we generated

our search terms (1). Search terms, Inclusion and exclusion criteria for study selection are

enclosed in Appendix 2.

The articles were assessed for eligibility in 2 stage process by a single reviewer. Initially by

reviewing study titles and abstracts and additionally by critical reading for full text was applied to

exclude the articles that did not meet the selection criteria. More literature was also identified by

citation tracking using reference lists from retrieved papers, after removing duplicates.

One researcher undertook the initial literature search, scanning abstracts to identify eligible

studies. If it was unclear as to whether the study met the selection criteria, advice was sought from

a second researcher and a consensus opinion made.

2.3 Data Extraction

Key data were independently extracted from the identified papers using a structured form

(extraction matrix). Data extraction forms included the key components of general study

information (title, author, and country of study), study characteristics (population data,

intervention, and comparator) and outcome.

2.4 Quality Assessment

All articles were assessed for quality, by two researchers, using the Effective Public Health

Practice Project (EPHPP)(10). A global scoring was given of strong, moderate or weak, based on six

criteria: overall study design, whether or not there was selection bias, confounding, blinding, data

collection method and finally a number of withdrawals and dropouts.

This standardized tool was developed by EPHPP in order to provide high-quality systematic

reviews for evidence to support the practice. This tool has been evaluated for content and initial

construct validity and inter-rater reliability.

2.5 Evidence Synthesis

A meta-analysis was not possible due to the heterogeneity of the interventions, settings,

participants, and outcome measures. Instead, a rating system of levels of evidence to draw

conclusions on effectiveness, based on previously used best evidence syntheses was used.

Three levels of strength based on the basis of study design, methodological quality (EPHPP)

were defined: STRONG, MODERATE, WEAK. Conclusions were drawn on the basis of the consistency

of results of studies with the highest available level of quality.

As per EPHPP recommendation (Appendix 3), we rated overall STRONG if no weak ratings,

MODERATE if one weak rating, and WEAK if 2 or more weak ratings of the 6 criteria: Selection Bias,

Study Design, Confounder, Blinding, Data Collection, and Withdrawal.

GLOBAL RATING FOR THIS PAPER:

1 STRONG (no WEAK ratings)

2 MODERATE (one WEAK rating)

3 WEAK (two or more WEAK ratings)

7 | P a g e

3. RESULTS

3.1 Study Selection

Figure 1 Prisma diagram for Medline and NHS EED search results

The search strategy in Medline and NSHEED using combinations of free search terms, as

mentioned above, yielded 37 articles, 2 were duplicate and excluded. Thirty-five articles were

scanned for their title and abstract and eventually 3 articles were excluded due to a non-relevant

outcome. After critically reading the full text and applying the selection criteria, 15 articles were

excluded due to different parameters, intervention, comparator, and reviews. The remaining 17

articles met the general inclusion criteria, while citation tracking led to the inclusion of 12 additional

potentially relevant articles.

Only one economic evaluation (5) and one HTA (8) were included while searching on NHS

EED.

The reason for excluding articles was due to one or more of the following reasons: 1) general

non-relevance, 2) different study type, not clinical trial or cost evaluation study, 3) different

comparator 4) different outcome measures or/and 5) insufficient data

3.2 Study characteristics

Population

There were no limitations on the number of population which ranged from 15 – 4119

participants. The study of (11) with 4119 participants was an outlier because the rest of the studies

range between 11 – 281 participants. Mean age and gender were clearly mentioned in all papers;

+ 12 potentially relevant articles from reference search

TOTAL of 29 ARTICLES

8 | P a g e

however, ethnicity was missing in most of them. Heterogeneity is overarching settings, age, gender

and inclusion criteria, which might constitute a threat to the external validity of the results of this

review. (Table.1)

Intervention

In all the studies the intervention groups were scanned by BU to measure intermediate

catheterization. Heterogeneity emerges from the intervention adopted since different ultrasound

bladder scanner models were used, BVI 2000, BVI 2500, BVI 2500+, BVI 3000, BVI 5000. (Table.1)

Settings and duration

Settings vary from one paper to another among postoperative patients, pediatric,

neurogenic, geriatric, postpartum, urology patients and patients in rehabilitation centers for long-

term care of different indications. In addition, the frequency with which the bladder was evaluated

was not completely documented while the duration of studies ranges between 2-24 months.

Outcome

The clinical outcome of our primary interest was accuracy in quantifying bladder volumes,

measured by a mean difference (ml), correlation coefficient (r2), or bladder distension defined as a

bladder volume >500 ml (%). Further health outcomes on patients, nurses and hospitals are

measured by different indicators like reduction of unnecessary catheterization, reduction in UTI

and antibiotic use. Cost savings were also measured in terms cost expenditure of time and of

human and material resources. ICER was not found in any of the studies.

9 | P a g e

TABLE 1: The characteristics of the study population, type, and duration of intervention and relevant outcome results

Arranged by descending date

# AUTHORS OBJECTIVES/

OUTCOME

STUDY

TYPE

COUNTR

Y

SETTINGS PARTICIPANTS INTERVENTION CLINICAL OUTCOME COST

EVALUATION

# INC SEX

N or %

of

female

s

AGE Device

model

Frequency

Follow-up

device

1 (12)

Is UBS a valid

technique for

measurement of

postpartum urinary

bladder volume?

Cohort

analytical

study

MALAYSI

A

Obstetrics

and

Gynecology

Dep.

190

Post-partum

women

All F 16-

47

Mean

26.9

BVI

3000

190:1 per

catheter

3 months

• 1ry: accuracy

measurement of BV in

postpartum women

• 2ry: correlation bet

body weight and

accuracy of

measurement

-

2 (13) Explore whether

close preoperative

ultrasound

monitoring starting

in the emergency

room (ER) could

prevent

postoperative

bladder distension

among acute

orthopedic patients

Randomiz

ed

control

trial

SWEDEN ER to an

orthopedic

ward for

acute

surgery

281 Inclusion

criteria were

admittance

via the ER to

an

orthopedic

ward for

acute surgery

171 F Above

16

BVI

3000

21 months

• 1ry: accuracy

measurement of BV in

postoperative

distention, defined as

a bladder volume

>500 ml.

• 2ry: UTI and hospital

length of stay.

-

3 (14) Compare the rates

of unnecessary

catheterization, UR

and UTI in post-

operative patients,

before and after

implementing a

bladder ultrasound

program in

neurosurgical units

Quasi-

experime

nt

TAIWAN Two

neurosurge

ry unit

/ National

University

Hospital

244

Age ‡18

Pts

hospitalized

in

neurosurgica

l units

119 F 63·3

± 14y

ears

in CG

55·6

± 18y

ears

in SG

BVI

5000

9 months • 1ry: bladder

distension, defined as

a bladder volume

>500 ml

• 2ry: Unnecessary

catheterizations

• 3ry: UTI in

postoperative pts

before and after

-

10 | P a g e

implementation of the

program

4 (15)

Monitoring urinary

bladder volume and

detecting

postoperative

urinary retention in

children with an

ultrasound scanner.

Quasi-

experime

nt

NORWAY Anesthesiol

ogy

Departmen

t /

University

Hospital

48

Children

0-15 years

- Mean

= 3y

BVI

3000

1 year

• Accuracy in children

above and below 3

years

-

5 (16) Detecting

postoperative

urinary retention

with an ultrasound

scanner

Quasi-

experime

nt

NORWAY postanesth

esia care

unit (PACU)

36 Pts

undergoing

spinal

anesthesia

19 F Mean

=50

(20-

86 )

BVI

2500+

1 year • Accuracy in post-

operative adults

-

6 (8) Economic model to

estimate cost

savings

Economic

model

Ontario

canada

complex

continuing

care (CCC)

facilities

50 Pts admitted

to CCC and

require

intermediate

catheterizati

on

1 year - • expected net

costs to a CCC

facility

• unnecessary

catheterization

and UTIs

avoided due to

adopting the

portable

bladder

7 (17)

Examine the impact

of using UB in

Reduction of urinary

tract infection and

antibiotic use after s

urgery

Quasi-

experime

nt

Geneva,

Switzerla

nd

Anesthesiol

ogy dep.

132

8

adult pts

scheduled

for

orthopedic or

abdominal su

rgery

Almos

t half

Mean

= 60

- 529 (phase

I), 499

(phase II),

and 300

pts during

the 2- year

follow-up

(phase III)

-

• the incidence

of UTI

• Adherence to

guidelines

during and after

the experiment

by 2 years

• Reduction of

unnecessary

catheterization

11 | P a g e

• Reduction in

UTI and anti

biotic use

8 (18) Compare the impact

of volume-

dependent

intermittent

catheterization

(VDIC) and time-

dependent

intermittent

catheterization

(TDIC) on financial

burden and clinical

outcomes in

patients with spinal

cord lesions (SCL).

Cohort

analytical

study

Israel Spinal

Rehabilitati

on dep.

24 Pts with

Spinal cord

lesion (SCL)

4 F Mean

=

20.6

BVI

5000

12-30 days • The number

of

catheterizations

per pt per day,

• the time

required to

perform volume

measurements

and

catheterizations

, their total cost

9 (19) Evaluate differences

between

BladderScan and

catheterization in

terms of the

expenditure of time

and of human and

material resources

A

prospecti

ve study

TAIWAN rehabilitati

on hospital

71 pts

undergoing

inpt or outpt

rehabilitation

therapy

31 F - BVI

3000

5 months • expenditure

of time and of

human and

material

resources

1

0

(20) Compare the

accuracy of portable

and stationary

ultrasonography

equipment in

estimating residual

bladder volume.

A

prospecti

ve study

TAIWAN rehabilitati

on hospital

64 Pts’

diagnoses

included

spinal cord

injury (n =

23), stroke

(n = 32),

traumatic

27 F BVI

3000

192:3 per

catheter

(3

independe

nt

examiners)

• The mean errors and

mean percentage

error resulting from

use of the 2 types of

equipment were

recorded

12 | P a g e

brain injury

(n = 6) and

other

conditions (n

= 3)

6 month

1

1

(21) Measure the

Effectiveness of the

portable UBS in the

measurement of

residual urine

volume after total

mesorectal

extirpation: and the

cost-benefit analysis

as compared with

postoperative

catheterization:

RCT

dealing

with the

economic

benefit

JAPAN Surgery

dep.

30 Pts with

after total

mesorectal

extirpation

13

female

s

avera

ge 69

BVI

3000

One year • Accuracy

• Cost benefit

1

2

(22) Evaluate accuracy of

PVI in an acute care

neuroscience unit

Cohort

analytical

study

CANADA acute care

neuroscien

ce unit

30

acute care

neuroscience

population,

suspected to

be retaining

urine

17 F Mean

65 y

BVI

5000

2 months • accuracy,

• Effect on nursing

practice in an acute

care neuroscience unit.

-

1

3

(23)

Evaluated the

usefulness of a

bladder scanner in

reducing the

frequency of

catheterization in

women prior to

laparoscopy

Prospecti

ve clinical

Study

UK Obstetrics

and

Gynecology

dep.

40

Women,

Prepared for

gynecologica

l laparoscopy

All F BVI

2500

6 months • accuracy in

quantifying bladder

volumes

• Reduce

unnecessary

catheterization

1

4

(24) Urinary Retention in

Patients in a

Geriatric

Rehabilitation Unit:

Prevalence, Risk

Factors, and Validity

Prospecti

ve clinical

Study

CANADA Geriatric

dep.

167 Elderly pts

with:

Impaired

recognition,

immobility,

hip fracture,

111

(66%)

Mean

80 y

Range

57-

95 y

BVI

2500+

13 month

s

• accuracy in

quantifying bladder

volumes in elder pts

-

13 | P a g e

of Bladder Scan

Evaluation

stroke,

diabetes

1

5

(25)

Efficacy of a

portable 3-

dimensional

ultrasound scanning

device in

measurement for

residual urine

volume in

ambulatory women

with urinary

incontinence,

Cohort

analytical

study

USA Center for

Aging and

Geriatric

dep.

95

Ambulatory

women with

urinary

incontinence.

All F Mean

age

67 y

BVI

2500

- • accuracy,

• Correlation bet age,

weight, BMI, parity,

hysterectomy , and

accuracy of

measurement

• Sensitivity and

specificity

1

6

(5) Determine The

effectiveness of

implementing a

bladder ultrasound

program in

orthopedic surgery

units

A quasi-

experime

nt

Minnesot

a

USA

Large

tertiary

care

hospital -

three units

of

orthopaedi

c surgery

103

proposed

sampling of

orthopedic

pts

47% Mean

63 y

BVI

2500

- • Number of

catheterizations

avoided: avoiding

unnecessary

catheterization

• Urinary tract

infections

Rates and

Costs.

• cost analysis

of UBS

acquisition

pt/ provider

(nurses)

Satisfaction

1

7

(11) Evaluate the

effectiveness of

the ultrasound in

the

determination of

urinary

volume in post-

operative patients

A quasi-

experime

nt

NETHERL

ANDS

Anaesthesi

ology dep.

c=

192

0+

I=

219

6

All patients

undergoing

orthopedic

surgery in

the

mentioned

period

62% Mean

45 y

BVI

3000

9 months • Number of

catheterizations

avoided: avoiding

unnecessary

catheterization

• 2ry: Number

of urinary

infections in

postoperative

pts

1

8

(26)

Examine the

accuracy of BVI

Prospecti

ve clinical

Study

Ontario,

Canada

urodynamic

unit

78 women

undergoing

uroflowmetry

in our

ALL F Mean

56 ±

14

(SD).

BVI

2500

80:1 per

catheter

accuracy in quantifying

bladder

volumes

-

14 | P a g e

urodynamic

unit

1

9

(27) Examine the

accuracy of BVI

Prospecti

ve clinical

Study

Netherla

nds

Pre- and

post-

induction

of

anesthesia

50 scheduled to

undergo

surgeries

requiring

anesthesia

and

catheterizati

on

aged

18–88

years

BVI

2500

50:3 per

catheter

accuracy in quantifying

bladder

volumes

-

2

0

(28) Evaluate the clinical

utility of a new

portable ultrasound

device (PUD) in the

management of

intermittent catheter

programs in pts with

neuropathic bladder

a

randomiz

ed

control

trial

Vancouv

er,

Canada

Tertiary

care center

providing

inpt and

ambulatory

rehabilitati

on services

38 pts with

neurologic

disabilities as

a result of

SCI or other

spinal

disorder.

>= 18 y

8 F Mean

36.5 y

portabl

e

ultraso

und

device

(PUD

1 month • evaluate the

frequency of

catheterizations,

• frequency of

overdistention, and

• pt satisfaction with

use of a new portable

ultrasound device (PUD)

in the management of

intermittent catheter

programs

-

2

1

(29) Assess the accuracy,

reliability, and

clinical utility of UB

Comparat

ive

analysis

UNITED

STATES

urology

clinic

249 Pts with

urologic

conditions

90 F Mean

73 ±

10

(SD).

BVI

2500

556:3 per

catheter

243 BVI

2500

303 BVI

2500+

14 month

s

(2 indep

examiners)

- • Reduction in

UTI incidence

• Cost savings

versus purchase

cost

2

2

(30) bedside

assessments of

bladder volumes by

portable bladder

ultrasound in place

of intermittent

Cost

analysis

Maryland

US

orthopedic

and

genitourina

ry

department

805 pts who had

an

orthopedic or

genitourinary

procedure

684 F Mean

74

(22-

103

BVI

2500

12 month - • rates of UTI

reduction

• expenditures

and cost-

savings

attributable to

15 | P a g e

catheterization : to

reduce the incidence

of nosocomial

urinary tract

infections

portable

bladder

ultrasound

2

3

(31)

Comparing

catheterization with

ultrasound scanning

Prospecti

ve clinical

Study

Maryland

US

Urology

/gynecolog

y clinic

72 women

presenting

for

urogynecolo

gical

evaluation

All F - BVI

2500

72:1 per

catheter

• accuracy in

quantifying bladder

volumes

2

4

(32) Investigate the

accuracy of a

portable ultrasound

scanner as an

alternative method

of measurement

Prospecti

ve clinical

Study

SINGAPO

RE

of Geriatric

dep.

46 Inpt at

geriatric dep,

Or outpt

attending

continence

clinic

34 F 40-

95 Y

BVI-

2500

180:20 per

catheter

2 months

• accuracy in

quantifying bladder

volumes

2

5

(33) Effectiveness of

bladder scan in

geriatric

rehabilitation

Prospecti

ve clinical

study

COLUMBI

A

acute

rehabilitati

on unit and

geriatric

unit

16 Geriatric pts - over

65

years

of age

BVI

2000

3 month - • Reduction in

unnecessary

catheterization

• Reduction in

UTI incidence

2

6

(34) Accuracy of portable

ultrasound scanning

in the measurement

of residual urine

volume

Prospecti

ve clinical

study

AUSTRAL

IA

Urology

dep.

100

Urology pts 49 F Mean

58 y

BVI

2500+

100:1 per

catheter

• accuracy in

quantifying bladder

volumes

-

2

7

(35) Accuracy of Bladder

volume estimation

in the elderly using

a portable

ultrasound-based

measurement device

Prospecti

ve clinical

study

CANADA Geriatric

and

urology

clinic

44 Pt attending

Geriatric

continence

clinic or

urology

clinic.

27 F Mean

= 76

BVI

2000

73:2 per

catheter

(2 diff

examiners)

• Accuracy,

• ease of use of

portable ultrasound

device in a geriatric

outpt population

-

16 | P a g e

2

8

(36) Accuracy of Bladder

volume

determination using

a dedicated,

portable ultrasound

scanner.

Prospecti

ve clinical

study

Seattle

US

urology

clinic and

spinal cord

injury unit

112 spinal cord

injury pts

- - BVI

2000

656:4 per

catheter

10-months

• accuracy in

quantifying bladder

volumes

-

2

9

(37) Evaluate Residual

urine volumes in pts

with spinal cord

injury

Prospecti

ve clinical

study

Seattle

US

Inpt

rehab/spin

al cord

15 Spinal cord

injured (SCI)

pts

4 F - BVI

2000

224:4 per

catheter

• accuracy in

quantifying bladder

volumes

-

N: number of patients, F: female, dep: department, SG: study group, CG: control group

17 | P a g e

3.3 Methodological quality

Since the nurses and practitioners had to be trained on the device and patients had to be

consented on the usage of the device, therefore the blinding section was not applicable in most of

the studies, except of few who did blind the results of 2 examiners from each other. In this regards,

we have concluded an overall rating with and without including blinding. Likewise, the dropouts and

withdrawals were not likely in most of the papers due to the successive examination of both

intervention and control in a short time period and mostly on the same patients.

Based on overall rating without blinding, 13 studies were MODERATE, 11 were STRONG, and

4 were WEAK. One study was not rated since it was an economic model (8)

TABLE 2: Description of key methodological properties and quality of eligible studies (based on

EPHPP)

Arranged by descending date

# Authors

Select

ion

Bias

2. Study

Design

3.

Confo

under

s

4.

Blinding

5.

Data

Collec

tion

Metho

ds

6.

Withdra

wals

And

Dropou

ts

Overall

Overall

Without

Blinding

1 (12)

M

PROSPECTIVE

CLINICAL

STUDY

S NA S NK WEAK MODERAT

E

2 (13) S RCT S NA S S MODERA

TE STRONG

3 (14) M QUASI M NA S NK WEAK MODERAT

E

4 (15) M QUASI S NA S NK WEAK MODERAT

E

5 (16) M QUASI S NA S NK WEAK MODERAT

E

6 (8) *

7 (17) M QUASI S NA S NK WEAK MODERAT

E

8 (18) S

COHORT

ANALYTICAL

STUDY

S NA S NK MODERA

TE STRONG

9 (19) M

PROSPECTIVE

CLINICAL

STUDY

S NA S NK WEAK MODERAT

E

1

0 (20) M

PROSPECTIVE

CLINICAL

STUDY

S S S NK MODERA

TE

MODERAT

E

1

1 (21) S RCT S NA S S

MODERA

TE STRONG

18 | P a g e

1

2

(22)

M

COHORT

ANALYTICAL

STUDY

S NA W S MODERA

TE STRONG

1

3

(Moselhi and

Morgan

2001)

M

PROSPECTIVE

CLINICAL

STUDY

S NA M S WEAK MODERAT

E

1

4 (24) M

PROSPECTIVE

CLINICAL

STUDY

S NA M NK WEAK MODERAT

E

1

5

(25)

M

COHORT

ANALYTICAL

STUDY

S NA S S MODERA

TE STRONG

1

6 (5) M QUASI S NA S S

MODERA

TE STRONG

1

7 (11) M QUASI S NA S NK

MODERA

TE

MODERAT

E

1

8 (26) M

PROSPECTIVE

CLINICAL

STUDY

S NA S NK MODERA

TE

MODERAT

E

1

9 (27) M

PROSPECTIVE

CLINICAL S NA S NK

MODERA

TE

MODERAT

E

2

0 (28) S RCT S NA S M

MODERA

TE STRONG

2

1 (29) M

PROSPECTIVE

CLINICAL

STUDY

S S S NK STRONG STRONG

2

2 (30) M

PROSPECTIVE

CLINICAL M W M NK WEAK WEAK

2

3 (31) M

PROSPECTIVE

CLINICAL

STUDY

W NA S NK WEAK WEAK

2

4 (32) M

PROSPECTIVE

CLINICAL

STUDY

S S S NK MODERA

TE STRONG

2

5 (33) M

PROSPECTIVE

CLINICAL

STUDY

S NA S NK WEAK MODERAT

E

2

6 (35) M

PROSPECTIVE

CLINICAL

STUDY

W NA S NK WEAK WEAK

2

7 (34) M

PROSPECTIVE

CLINICAL

STUDY

S NA M NK WEAK WEAK

2

8 (36) M

PROSPECTIVE

CLINICAL

STUDY

S S S NK MODERA

TE STRONG

19 | P a g e

2

9 (37) M

PROSPECTIVE

CLINICAL S S S NK

MODERA

TE STRONG

S: strong, M: moderate, W: weak, NK: not known, NA: not applicable

*economic model

20 | P a g e

3.4 Summary on Accuracy of Bladder Scanners Results

Accuracy in terms of mean difference, correlation, sensitivity, and specificity (Table 3)

There was a controversy between studies in terms of overestimation and underestimation of

device BVR compared to actual catheterization BVR. However, all BVI models have shown high validity

compared to intermediate cauterized volume, measured by significant correlation ranging from r2=

0.78 - 0.94, which was high. Device accuracy, sensitivity, and specificity were also measured in some

studies, showing promising results 94%, 97% and 91% respectively. (Table 3, 4)

Nineteen studies reported that BU had acceptable levels of clinical effectiveness (reliability) in

terms of volume mean difference between BU measured volume and catheterized volume. Some

papers reported overestimation of PVR and others reported under- estimation, with overall

acceptable mean error range from -81 to +105 ml (22, 24). The difference also between the two

methods was not affected by parity, age, body mass index (BMI), and uterine size (12).

In Marks et al, BVI underestimated bladder volume in women more than in men but

generally accurate 94% and was correlated closely (r2 = 0.90, P < .001) (29).

For low volumes of PVR, BU is highly sensitive and moderately specific, like in Goode et al

study (r2 = 0.60, P < .001) showing high specificity and moderate sensitivity of 96.5% and 66.7%

in detecting PVR ≥100 ml (25). While high PVR volumes, it was moderately sensitive and highly

specific (26). Reported sensitivities ranged from 0.67 to 0.97, and reported specificities ranged

from 0.63 to 0.97.

Generally, the accuracy of BU is reasonable and acceptable in patients with urologic

conditions, which might be altered by gender and volume of PVR. Accuracy is proved to be lower in

women and in PVR higher than 150 ml.

Repeated consecutive measurements do not significantly improve the correlation of a BU

reading with catheterization reading, however, simple training increase inter-rater reliability.

Another study showed Portable BU was less accurate that stationary BU, however, more

convenient with acceptable clinical use. The mean absolute errors were 34.4 mL (69.5%, P < .05)

and 21.9 mL (16.6%, P < .05) for portable and stationary BU. Portable and stationary ultrasounds

had sensitivities of 80% and 87%, respectively, and specificities of 90% and 100%, respectively (20).

Different BVI devices were tested in different settings, for their reliability, and different

results were concluded, as follows:

Pediatrics

One study in Norway on children confirmed that BVI 3000 reliability was good in children

above the age of 3 years and underestimated in younger children (15).

Patients with Neurogenic Conditions

Another study on patients admitted in urology clinic and spinal cord injury unit in Seattle

indicated that the BVI 2000 is an accurate alternative to catheterization for determining BVI residual

volume (36).

Patients with Urologic Conditions

Studies conducted on patients with urological conditions, were two of them showed an

overestimation of BVI residual volume (25, 34) and another two showed underestimation (29) (26).

However, all of them showed high correlation with actual volume and overall accuracy which

assumes that BVI was an accurate and reliable device for bladder volume measurement in adult

urology outpatients.

21 | P a g e

Peri - postoperative and acute care patients

Six studies in Peri-operative populations found BU reasonably acceptable, although there are

controversial results. one study of Moselhi et al found that the devices overestimated catheter

derived bladder volumes by 39 ml (23). while another 3 studies found the opposite—that the

devices underestimated catheter bladder volume by 105mL, 21 ml and 7% (16, 22, 27).

All Study investigators concluded that BU can be used peri-operatively to establish bladder

volume, taking into account mean error (under- estimation or overestimation) of the bladder

volume, owing to the good agreement between BU and catheter estimates of PVR.

Rehabilitation settings: Geriatrics and spinal cord injuries

Two studies examined the reliability of BVR measurement by BU comparing it with the

urethral catheterization in incontinent patients with spinal cord injuries (SCI) in rehabilitation

settings, which showed an acceptable overestimation of PVR (19, 20, 37).

Another three studies examined the reliability of BVR measurement by BU in incontinent

geriatric populations in rehabilitation settings, which showed an acceptable overestimation (32, 35)

and underestimation (24) compared to true bladder volume.

In conclusion , despite the controversy results (overestimation and underestimation) and

lower reliability for volumes greater than 200 ml, 5 studies estimate the ultrasonic device efficient

enough to recommend its Geriatric Use.

Post-Partum Care & Gynecology Dep

Two studies concluded that BVR measurement showed underestimation which was not

significant and results were highly correlated with true residual volume obtained by catheterization

in immediate postpartum period. The difference also between the two methods was not affected by

parity, age, body mass index (BMI), and uterine size (12).

The accuracy of measurement is affected by body weight and the increasing amount of BVR.

However, the result of this study only apply to postcesarean section women, and therefore, could

not be generalized to all patients (12, 31).

22 | P a g e

TABLE 3 summary of accuracy for estimating bladder volume with the bladder scanner

Arranged by patients population

Study Conditions Population

M/F

Mean age

context

Correlation

coefficient (r)

Mean volume

difference

True/ultrasound

(ml)

Bladder distension

(%)

Contol:study gp

Accuracy rate sensitivity

specificity

conclusion

1 (15) PEDIATRIC

CARE

N=48

Children

0-15 yrs

Urinary retention

4 ml (SD = 25 )

children above the

age of 3 years

and -18 ml (SD =

19 ml) in younger

Reliability was good for

children above the age of 3

years. The volume was

underestimated in younger

children

2 (36) NEUROGENIC

PTS

N: 11

NC

spinal cord injury

r = 0.79,

P < .05

significant correlation

coefficient indicated that the

BVI is an accurate

alternative to catheterization

for determining bladder

volumes

3 (25) UROLOGY PTS N: 95 F

67 years

Urinary

incontinence in

ambulatory women

17 mL

P < .0001;

95% (CI) 8–25 mL

Sensitivity of

66.7% and a

specificity of

96.5% in

detecting PVR >

or = 100 ml.

Overestimation by 17 ml,

but highly correlated with

the actual residual volume.

4 (26) UROLOGY PTS N: 78 F

56+-14 y

urology unit

most accurate

(60.6%) when the

readings were

below 50 ml and

least accurate

(10%) when

readings were

higher than 150

ml

Underestimate and

correlated poorly with the

actual residual volume.

5 (29) UROLOGY PTS

(OLDER)

Group 1: 182

92/90

60.6 years

Group 2: 57

urology unit

r = 0.90

P < .001

overall accuracy of

94%

sensitivity of 97%,

a specificity of

91%

underestimated by 10 cc in

men and 20 cc in women,

yet closely correlated with

the actual residual volume,

23 | P a g e

with high sensitivity and

specificity

6 (34) UROLOGY PTS Group 1: 50

28/22 (59.5 years)

Group 2: 50

23/27 (58.1 years)

urology unit

(studies

urodynamic)

41 ml. (95% CI 26

to 55 ml.).

24 ml. (95% CI 17

to 31 ml.)

0.86 (R2 = 0.73)

0.97 (R2 = 0.94)

Overestimation with Low

mean difference but highly

correlated

7 (13) PERI & POST-

OPERATIVE &

ACUTE CARE

PTS

N:281

110:171

Above 16

Orthopedic pts

The bladder

distention > 500

ml: 27.1% vs

17.0%;

Respectively

Postoperative bladder

distension was significantly

higher in the control group.

8 (14) PERI & POST-

OPERATIVE &

ACUTE CARE

PTS

244

125:119

63·3 ± 14years in

the control group,

55·6 ± 18years in

the study group

r= 0·86,

0·87

nurses ,

researchers

respectively

The bladder

distention > 500

ml: 13·4% and

20·3%,

respectively

These measurements

demonstrated high

consistency and accuracy

bet 2 examiners

9 (16) PERI & POST-

OPERATIVE &

ACUTE CARE

PTS

N:36

19/17

50 Yr

postanesthesia care

unit (PACU)

-21.5mL Underestimated 21.5 ml

(95% CI: 147 - 104mL0

But acceptable

1

0

(23) PERI & POST-

OPERATIVE &

ACUTE CARE

PTS

N:40 F

Before laparoscopy

+ 39ml Overestimated + 39 ml

(95%CI )

But acceptable

1

1

(22) PERI & POST-

OPERATIVE &

ACUTE CARE

PTS

N:30

neuroscience unit

mean error of -

105 mL

slightly underestimated the

catheterized volumes, but

were highly correlated with

catheterized volumes

24 | P a g e

1

2

Brouwer el

al

PERI & POST-

OPERATIVE &

ACUTE CARE

PTS

N=50

18-80 y

Before anesthesia

r2 = 0.94 in

awake

patients (P <

.01) and

r2 = 0.95 in

Anesthetized

patients (P <

.01).

Underestimate

7% across the total

volume range of

17 mL to 970 mL

Underestimation of PVR, on

average by 7%

Underestimation of PVR was

greater in females than in

males (P < .02).

Correlation was good in

awake and anesthetized pts

1

3

(38) REHABITATION

: GERIATRIC

AND LONG

TERM CARE

N: 64

37/27

NC

spinal cord injury,

stroke, traumatic

brain injury and

other conditions

34.4 mL

(69.5%, P < .05)

for portable

bladder

ultrasound

21.9 mL

(16.6%, P < .05)

for the stationary

ultrasound

Portable/stationar

y sensitivities :

80%and 87%, resp,

Specificities:

90% and 100%,

resp

portable ultrasounds is less

accurate than stationary

ultrasounds, particularly

with small bladder volumes.

However, portable

ultrasonography is more

convenient to use and has

an acceptable accuracy for

clinical use.

1

4

(24) REHABITATION

: GERIATRIC

AND LONG

TERM CARE

N: 167

57/110

80 ± 7.62 years

Rehabilitation Unit

Geriatric

r: 0.87 Error

average - 80,6ml

(P = 0.001)

Volume ≤150ml

underestimated true bladder

volume by an average of

80.6 mL but highly

correlated

1

5

(32) REHABITATION

: GERIATRIC

AND LONG

TERM CARE

N: 46

12/34

79 ± 8.2 years

Geriatric Medical

Unit

r: 0.78 and

0.76

The mean

absolute error of

the scanner was

52 mL.

For volumes below

200 mL and 100

mL, this was 36

mL and 24 mL

respectively

86 to 89%

according to the

cutoff point

Overestimation proportional

to the residual volume but

highly correlated

1

6

(35) REHABITATION

: GERIATRIC

AND LONG

TERM CARE

N:36

geriatric outpt

population

correlation

coefficients

were highly

significant

Acceptable overestimation

25 | P a g e

1

7

(37) REHABITATION

: GERIATRIC

AND LONG

TERM CARE

N=15

Spinal cord injured

(SCI) pts

r2 = 0.80. average error was

18% for

catheterized

volumes within

the range 50-

700ml

Highly correlated results

1

8

(12) POST-PARTUM

CARE &

GYNECOLOGY

DEP.

N:190 F

16 - 47 yrs

No sig diff UBS is comparable with

urethral catheterization.

However, accuracy is

affected by body weight and

increasing amount of BV.

1

9

(31) POST-PARTUM

CARE &

GYNECOLOGY

DEP.

N=72

gynecology clinic

r = 0.924;

P < 0.001

17 ml Underestimation by 17 ml

but not significant,

measures highly correlated

with the PVR obtained by

catheterization

N: number of patients, NK: not known, r: correlation coefficient of pearson, r2: correlation, CI: confidence interval

26 | P a g e

3.5 Summary on Health Outcomes of Bladder Ultrasound

Reduction in Unnecessary Catheterization and Urinary Tract Infections (Table 4)

Thirteen studies included health-related outcomes, which was divided into many indicators:

reduction of unnecessary catheterization, reduction in UTI (CAUTI) and antibiotic use. Results for an

avoidance of unnecessary catheterization ranged from 14% to 80% in Lee et al. and Fred et al.

respectively. Also, reduction in UTI was as high as 72% in Slappendal et al. and as low as 9% in

Frederickson et al. antibiotic use reduction was measured in a study of Stephan et al to be 13 %.

In a very high study sample of Stephan et al, a comprehensive reduction in antibiotic treatment

from 17.9 to 15.6% (P<.005) significantly due to a reduction of UTI from 10.4 to 3.9 % (P<.001) (17).

Patient’s and nurses satisfaction with the device was also measured in some papers like

Fredrickson et al. showing high satisfaction rate of 93% and 97%, respectively (5).

Different settings with different durations had different reduction rates, as mentioned below:

Pre - postoperative and acute care patients

Seven studies concluded that there was a potential relationship between the implementation of

portable bladder ultrasound with reductions in catheterizations and subsequent UTI. They also

recommended this device to be a quick and effective technique for reducing the frequency of

preoperative catheterization. (11, 14, 17, 21-23, 30)

Geriatric Medicine Patients and Long-Term Care Facility Patients

Authors of 3 studies stated that PVI reduced hospital costs by decreasing the numbers of

catheterizations, UTIs, and nursing time involved. (5, 19, 33). The result revealed more time required

for catheterization (3 to 8 times) than for the BU, which further emphasize that BVI is a time-saving

method and in terms of medical human resources costs as well (19). The author also reported on

patients and nurses satisfaction to be 93% and 97%, respectively (5).

Spinal And Neurogenic Bladder Problems

Economic impact of BU in patients with spinal cord lesions (SCL), disclosed a significant

reduction in number of catheterizations per patient per day, time required to perform volume

measurements and catheterizations, and their total cost, by approximately 44, 49, and 46%

respectively by using BU (18) . While Anton et al. showed a significant reduction (P = .026) in the mean

frequency of the catheterization in the intervention group (2.99) compared to the control group (4.19)

(28).

Cost savings and economic models (Table 4)

One study estimated a cost reduction of $680 for every UTI prevented by using the bladder

ultrasound, demonstrating that the cost of the BVI ($8300) would be retrieved after 200 bladder

scans. However, limitations to this study were the lack of formal economic analysis in the study and

cost analysis was based on author opinion and the study methodological quality was graded week.

(30).

Another result indicated a possible $3.64 cost savings of each catheter tray supply and $680

cost savings per each UTI reduction. These were further computed per reduction rates and an

estimation of 3 years of ultrasound machine use would be needed to recover the acquisition cost of

BVI 2500 (5).

In Ontario 2006, an economic model revealed that about 169 catheterizations and 1 UTI were

avoided daily in a typical Complex Continuous Care facility. With the adoption of BU, total annual cost

to a CCC facility (including catheter costs, nurse time, and UTI treatment costs but excluding device

costs) was valued to be $35,770 and $247,835 (without the adoption of this technology). The

difference in cost savings between the 2 methods would be $212,065 cost savings over 1 year(8)

.

27 | P a g e

TABLE 4 summaries of published results for UTI reduction and avoiding unnecessary catheterization with the bladder scanner

Study Conditions No of subjects Catheter

avoided, %

UTI reduction, % Time

required, %

Satisfaction

rate of

patients and

nurses

Cost saved conclusion

1 (14) POST-

OPERATIVE &

ACUTE CARE

PTS

N:244

63 years

neurosurgical

units in Taiwan

9 months

35.3% reduced

to 7%

After 3

months

(dec by 80%)

3.47% reduced

to 2.87%

after 3 months

, to 1.39%

after 6 months

(dec by 60%)

75.7% of

patients were

willing and

satisfied with

BVI as an

alternative

2 (17) POST-

OPERATIVE &

ACUTE CARE

PTS

N: 1328

60 years

Anesthesia

unit in

Switzerland

2 follow-up

years

10.4 to 3.9 %

(P<.001)

(Dec by 62.5%)

Antibiotic treatment

decreased from

17.9 to 15.6%

(P<.005)

3 (23) PRE-

OPERATIVE &

ACUTE CARE

PTS

N:40

women prior

to laparoscopy

UK

6 months

65% avoided

4 (22) POST-

OPERATIVE &

ACUTE CARE

PTS

N: 30

65 years

Acute care/

Neuroscience

unit

Canada

2 months

32% avoided

28 | P a g e

5 (21) POST-

OPERATIVE &

ACUTE CARE

PTS

N:30

69 years

Surgery

department

Japan

12 months

38% avoided 17.4 catheters

saved for each pt.

6 (30) POST-

OPERATIVE &

ACUTE CARE

PTS

N: 805

74 years

Orthopedic

surgery units

urological or

gynecological

12 months

Reduced to

22 %

Dec by 50% The cost of each UTI

incidence was

estimated at $680

(US) , means

1 portable bladder

device needed to be

used 200 times in

order to recover the

purchase cost (list

price purchased at

$8,300[US]

7 (11) POST-

OPERATIVE &

ACUTE CARE

PTS

Before, N:

1920

45.7 years

After, N: 2196

45.2 years

Orthopedic

surgery units,

NL

9 months

31% reduced

to 16%,

(15% avoided)

Number

decreased from

18 to 5.

(Dec by 72%)

Number of

catheters used

decreased from 602

to 349

statistically

Significant (P <

.05) reduction

in the need for

urinary

catheterizations

and the

likelihood of

UTIs.

8 (19) REHABITATION

: GERIATRIC

AND LONG

TERM CARE

N: 71

Rehabilitation

hosp.

Taiwan

time required

for

catheterizatio

n was 3 to 8

29 | P a g e

5 months times higher

than

BladderScan.

9 (5) REHABITATION

: GERIATRIC

AND LONG

TERM CARE

N: 50

intervention

N:53 control

General

Surgery (uro,

gynecology

and colon)

61 ± 17 years

(Orthopaedics)

63 ± 15 years

USA

1.96 reduced

to 1.68

(14 %

avoided)

13% to 4%

(Dec by 9%)

93% of pts

and 97% of

nurses

additional cost of

$676 per admission

$2886 cost savings

over 1 year

3 years of

ultrasound machine

use would be

needed to recover

the acquisition cost

1

0

(33) REHABITATION

: GERIATRIC

AND LONG

TERM CARE

N: 16

83 years

Rehabilitation

Unit, Geriatric

(orthopedics,

stroke)

3 months

47% avoided 50% reduced to

12 %

(Dec by 38%)

1

1

(8) REHABITATION

: GERIATRIC

AND LONG

TERM CARE

N=50

complex

continuing

care (CCC)

facilities

economic

model

total annual cost

was estimated at

$35,770 with the

adoption of the

bladder scanner

technology.

Without the

adoption of the

technology, the

cost to a typical

CCC facility was

estimated at

$247,835.

30 | P a g e

$212,065 cost

savings over 1

year

1

2

(18) SPINAL AND

NEUROGENIC

BLADDER

PROBLEMS

N=13

SCL pts

44% avoided Number

decreased from

3 to 0

49% lower in

IG

46% lower in IG

1

3

(28) SPINAL AND

NEUROGENIC

BLADDER

PROBLEMS

N: 38

bladders

neurogenic

after

cord injury

Rehabilitation

Unit

Mean

frequency of

catheterizatio

n decreased

from (4.19) to

(2.99)

29% avoided

31 | P a g e

4. DISCUSSION

Device accuracy

Most of the studies with strong and moderate methodology quality would recommend the

use of bladder ultrasound device as an alternative to catheterization in identifying the intermediate

PVR volume. Despite lower reliability for volumes greater than 200 ml, however, many studies

estimated that the device is accurate and efficient enough to be recommended for clinical use. Yet,

attention should be given to certain conditions including obesity, the presence of abdominal masses

and pregnancy, should be ensured; as such conditions may change the accuracy of the detection of

urinary residue by BU.

Although the studies used different BVI models, where some revealed overestimation and

others underestimation of urine volume measurements, however; their validity was supported by

high correlation between different examiners and high correlations with using intermittent

catheterization. Results can be generalized revealing accurately of bladder volume assessment by

bladder scanners, in spite of different models, users, patient positions; diagnosis, or healthcare

setting.

Patient health Outcomes – Medical, Clinical

Seven studies with sufficient sample size demonstrated reduction rate in unnecessary

catheterizations and UTIs up to 80%; 72%, respectively. The systematic use of the device will also

reduce patient discomfort, and also help to preserve patient dignity, based on satisfaction surveys

among nurses and patients.

Economic Impact

No complete economic evaluations were found to document the intervention's cost-

effectiveness. Three studies calculated the cost savings in private hospital settings, pertaining to

saved nursing time for facility staff through avoided catheterizations, and costs of treatment and

days of hospitalization associated with CAUTI. Additional training packages, batteries, and

maintenance should also be considered.

Two authors estimated a 3.64 cost of each catheter tray supply and $680 cost per each UTI

reduction, demonstrating that the cost of the BVI 2500 ($8300) would be retrieved after 200

bladder scans (30). In case of Fredrickson who conducted a partial economic evaluation, showing

14% and 9 % reduction in unnecessary catheterization and UTI, an estimation of 3 years of

ultrasound machine use would be needed to recover the acquisition cost of BVI 2500 (5).

A third HTA study in Ontario 2006 revealed that about 169 catheterizations and 1 UTI were

avoided daily in a typical Complex Continuous Care facility. The difference in cost savings between

the 2 methods would be$212,065 over 1 year for 50 patients (including catheter costs, nurse time,

and UTI treatment costs but excluding device costs) (8)

Several thousand of populations would benefit from this technology. However, it needs to be

quantified per each country or even smaller healthcare settings incontinence prevalence and

incidence.

Limitations

Several limitations apply this study. There were very few RCTs, although randomization may

have been appropriate in examining health outcomes, such as reductions in catheterizations and

UTI rates. Likewise, attrition rate and dropout rate was not clearly mentioned in most of the papers,

which negatively affected its methodological quality. Moreover, very few studies used blinding

techniques to investigators to prevent examiner bias. Blinding was not applicable in most of the

studies due to nature of the intervention which needed previous training to nurses and signed

32 | P a g e

consent from patients. The quality assessment tool used EPHPP was quite sharp which might have

decreased the overall quality of most studies.

Since the detection of urinary residue in the bladder is dependent on the examiners,

therefore; the methods and length of training should have been mentioned clearly, in order to

reduce the risk and threat of any internal validity of the results due to untrained nurses.

In most of the studies, samples were by convenience and tended to be too small to produce

sufficient power to identify differences between groups or over time which threaten the external

validity. Another threat of publication bias is due to our English language limitation to the extracted

papers, which might have been neglected important articles of an added value to our SR.

Studies also used different designs and population to assess effectiveness and reported on a

variety of different outcome measures and heterogeneity of studies, making it difficult to compute

all significant results together, and further develop a meta-analysis.

Complete economic evaluations on the device were missing, with only a few partial economic

evaluations on cost savings were conducted on a small scale, hospital level and not healthcare level.

Implications for research

Most of the literature available on BU technology addresses the accuracy of the equipment,

while little research on the clinical outcomes or benefits to the intervention. Larger sample sizes

should be also considered to document the impact of BU use on UTI rate and costs. Full economic

evaluations are needed and HTAs have to report on ICER rather than being just a review. More

satisfaction surveys on nurses and patients are needed to produce more evidence while including

also adverse effects of the device which was not tackled before in any paper.

5. CONCLUSION

Research has highly progressed from providing evidence accuracy to evaluation of the

clinical benefits of the bladder ultrasound scanner. In spite of the limitations of these studies, there

is some consistency in findings of accuracy, benefits, and satisfaction.

Based on existing evidence, the benefits of using bladder scan outweigh the risks using

intermittent catheterization. Since the intervention turned out to be more effective than the current

clinical routine already implemented, decision makers can choose to allocate resources differently.

However; there is a limited evidence of intervention's cost-effectiveness which is measured by its

impact on clinical outcomes, complications, cost, and patient/provider satisfaction.

6. RELEVANCE TO CLINICAL PRACTICE

Hospitals and nurses should follow Urinary retention protocols which are a type of catheter

restriction protocols that often incorporate the use of a portable bladder ultrasound to verify

retention prior to catheterization (6). BU are often purchased through operating budgets of

individual institutions and departments but sometimes under-used or misused due to lack of

efficient training for examiner (nurses and specialists), which limits its utility (7, 8). In practice, UB

should be commonly used by nurses and specialists in postoperative units, mainly obstetric-

gynecology units, complex continuing care, general practice, long-term care, home care and

rehabilitative units. This will limit unnecessary catheterization and reduce patient discomfort, costs

and days of hospitalization linked with urinary tract infection caused by catheterization.

33 | P a g e

APPENDIX 1: List of abbreviations

BVI Bladder volume instrument

BU Bladder ultrasound

CAUTI Catheter-associated urinary tract infection

CADTH Canadian Agency for Drugs and Technologies in Health

CBA Cost-benefit analysis

CEA Cost-effectiveness analysis

CHEC Consensus Health Economic Criteria

CUA Cost-utility analysis

CCA Cost-consequences analysis

CMA Cost-minimization analysis

DALY Disability-adjusted life years

EBM Evidence-based medicine

GRADE Group Reading Assessment and Diagnostic Evaluation

HAI healthcare-associated infection

NICE National Institute for Clinical Excellence

PICO People, Intervention, Comparator, Outcome

PRISMA Preferred Reporting Items for Systematic Reviews and Meta-

QALY Quality adjusted life years

SR Systematic review

UBS Ultrasound Bladder Scan

UR Urinary retention

UTIs Urinary tract infection

34 | P a g e

APPENDIX 2: Search string, inclusion, and exclusion criteria

MEDLINE: (Bladder-Scan[Text] OR Bladder Scan[Text] OR Bladder Scanner [Text] OR Bladder

Ultrasound[Text] OR Bladder Scanning[Text] OR Portable Ultrasound Device[Text]) AND Urinary Tract

Infection [MeSH] . The search was limited to humans and English (limit: ‘Humans ‘and ‘English’).

NHS EED: Bladderscan [any field] OR bladder scanner [any field] OR Bladder Ultrasound [any field]

INCLUSION CRITERIA

Based on PICOTT and the author´s own perception and interest, inclusion criteria were

created, as follows:

• Study design and methods that were described clearly: Any clinical trial (RCT, Quasi, or any

prospective clinical study), and any Economic evaluation (cost effective study, HTA, BIA. Etc. )

were used;

• Relevant population: target population was people hospitalized for treatment with a need to

evaluate bladder urinary volume;

• Relevant comparator: ultrasound bladder scan were compared with catheterization as normal

care;

• Relevant outcome: The paper included at least one of the following outcomes:

o Accuracy in measuring urine volume (mean difference, OR)

o Reduction in incidence of UTI (% or number)

o cost-benefit (in monetary value) or Cost-effectiveness in terms of incremental cost-

effectiveness ratio (ICER)

• Studies from (01-1-1985 till July 2016) were included, with no age restriction.

• English-language articles

EXCLUSION CRITERIA

A study was excluded if:

• Duplicate publications

• Nonsystematic reviews, letters, and editorials

• Non-English-language articles

• Animal and in-vitro studies

• Case reports

• the paper has a different study design, different study population, different comparators,

• The paper did not report any of the above-mentioned outcomes,

• Insufficient data (sample characteristics and dimensions unspecified)

35 | P a g e

APPENDIX 3: EPH PP GLOBAL SCORING

36 | P a g e

REFERENCES

1. Palese A, Buchini S, Deroma L, Barbone F. The effectiveness of the ultrasound bladder

scanner in reducing urinary tract infections: a meta-analysis. Journal of Clinical Nursing.

2010;19(21-22):2970-9.

2. Mevcha A, Drake MJ. Etiology and management of urinary retention in women. Indian Journal

of Urology : IJU : Journal of the Urological Society of India. 2010;26(2):230-5.

3. Saint S, Greene M, Kowalski CP, Watson SR, Hofer TP, Krein SL. Preventing catheter-

associated urinary tract infection in the united states: A national comparative study. JAMA Internal

Medicine. 2013;173(10):874-9.

4. Boyer DR, Steltzer N, Larrabee JH. Implementation of an evidence-based bladder scanner

protocol. J Nurs Care Qual. 2009;24(1):10-6.

5. Frederickson M, Neitzel JJ, Miller EH, Reuter S, Graner T, Heller J. The implementation of

bedside bladder ultrasound technology: effects on patient and cost postoperative outcomes in

tertiary care. Orthopedic nursing. 2000;19(3):79-87.

6. Meddings J, Rogers MAM, Krein SL, Fakih MG, Olmsted RN, Saint S. Reducing unnecessary

urinary catheter use and other strategies to prevent catheter-associated urinary tract infection: an

integrative review. BMJ Quality & Safety. 2013.

7. Stevens E. Bladder ultrasound: avoiding unnecessary catheterizations. Medsurg Nursing.

2005;14(4):249.

8. Ontario HTA. Portable bladder ultrasound: an evidence-based analysis. Medical Advisory

Secretariat (MAS). 2006;6(11):1-51.

9. Scotland QI. Portable bladder ultrasound: an evidence-based analysis. NHS QIS 2010.

10. tools E. Effective Public Health Practice Project

http://www.ephpp.ca/PDF/Quality%20Assessment%20Tool_2010_2.pdf. 2010.

11. Slappendel R, Weber EW. Non-invasive measurement of bladder volume as an indication for

bladder catheterization after orthopaedic surgery and its effect on urinary tract infections. European

journal of anaesthesiology. 1999;16(8):503-6.

12. Nusee Z, Ibrahim N, Rus RM, Ismail H. Is portable three-dimensional ultrasound a valid

technique for measurement of postpartum urinary bladder volume? Taiwan. 2014;53(1):12-6.

13. Joelsson-Alm E, Ulfvarson J, Nyman CR, Divander MB, Svensen C. Preoperative ultrasound

monitoring can reduce postoperative bladder distension: a randomized study. Scandinavian Journal

of Urology & Nephrology. 2012;46(2):84-90.

14. Lee YY, Tsay WL, Lou MF, Dai YT. The effectiveness of implementing a bladder ultrasound

programme in neurosurgical units. J Adv Nurs. 2007;57(2):192-200.

15. Rosseland LA, Bentsen G, Hopp E, Refsum S, Breivik H. Monitoring urinary bladder volume

and detecting post-operative urinary retention in children with an ultrasound scanner. Acta

Anaesthesiol Scand. 2005;49(10):1456-9.

16. Rosseland L, Stubhaug A, Breivik H. Detecting postoperative urinary retention with an

ultrasound scanner. Acta Anaesthesiologica Scandinavica. 2002;46(3):279-82.

17. Stephan F, Sax H, Wachsmuth M, Hoffmeyer P, Clergue F, Pittet D. Reduction of urinary tract

infection and antibiotic use after surgery: a controlled, prospective, before-after intervention study.

Clinical infectious diseases : an official publication of the Infectious Diseases Society of America.

2006;42(11):1544-51.

37 | P a g e

18. Polliack T, Bluvshtein V, Philo O, Ronen J, Gelernter I, Luttwak ZP, et al. Clinical and economic

consequences of volume- or time-dependent intermittent catheterization in patients with spinal

cord lesions and neuropathic bladder. Spinal Cord. 2005;43(10):615-9.

19. Teng C-H, Huang Y-H, Kuo B-J, Bih L-I. Application of portable ultrasound scanners in the

measurement of post-void residual urine. Journal of Nursing Research. 2005;13(3):216-24.

20. Huang YH, Bih LI, Chen SL, Tsai SJ, Teng CH. The accuracy of ultrasonic estimation of bladder

volume: a comparison of portable and stationary equipment. Arch Phys Med Rehabil.

2004;85(1):138-41.

21. Araki, Ishibashi, Sasatomi, Kanazawa, Ogata, Shirouzu. Effectiveness of the portable

ultrasound bladder scanner in the measurement of residual urine volume after total mesorectal

extirpation. Minimally invasive therapy & allied technologies : MITAT : official journal of the Society

for Minimally Invasive Therapy. 2003;12(5):245-8.

22. O'Farrell B, Vandervoort MK, Bisnaire D, Doyle-Pettypiece P, Koopman WJ, McEwan L.

Evaluation of portable bladder ultrasound: accuracy and effect on nursing practice in an acute care

neuroscience unit. J Neurosci Nurs. 2001;33(6):301-9.

23. Moselhi M, Morgan M. Use of a portable bladder scanner to reduce the incidence of bladder

catheterisation prior to laparoscopy. Bjog. 2001;108(4):423-4.

24. Borrie MJ, Campbell K, Arcese ZA, Bray J, Hart P, Labate T, et al. Urinary retention in patients

in a geriatric rehabilitation unit: prevalence, risk factors, and validity of bladder scan evaluation.

Rehabilitation Nursing. 2001;26(5):187-91.

25. Goode PS, Locher JL, Bryant RL, Roth DL, Burgio KL. Measurement of postvoid residual urine

with portable transabdominal bladder ultrasound scanner and urethral catheterization. Int

Urogynecol J Pelvic Floor Dysfunct. 2000;11(5):296-300.

26. Alnaif B, Drutz H. The accuracy of portable abdominal ultrasound equipment in measuring

postvoid residual volume. Int Urogynecol J Pelvic Floor Dysfunct. 1999;10(4):215-8.

27. Brouwer TA, Eindhoven BG, Epema AH, Henning RH. Validation of an ultrasound scanner for

determing urinary volumes in surgical patients and volunteers. Journal of clinical monitoring and

computing. 1999;15(6):379-85.

28. Anton HA, Chambers K, Clifton J, Tasaka J. Clinical utility of a portable ultrasound device in

intermittent catheterization. Archives of physical medicine and rehabilitation. 1998;79(2):172-5.

29. Marks LS, Dorey FJ, Macairan ML, Park C. Three-dimensional ultrasound device for rapid

determination of bladder volume. Urology. 1997;50(3):341-8.

30. Moore DA, Edwards K. Using a portable bladder scan to reduce the incidence of nosocomial

urinary tract infections. Medsurg nursing : official journal of the Academy of Medical-Surgical

Nurses. 1997;6(1):39-43.

31. Bent AE, Nahhas DE, McLennan MT. Portable ultrasound determination of urinary residual

volume. Int Urogynecol J Pelvic Floor Dysfunct. 1997;8(4):200-2.

32. Ding YY, Sahadevan S, Pang WS, Choo PW. Clinical utility of a portable ultrasound scanner in

the measurement of residual urine volume. Singapore Med J. 1996;37(4):365-8.

33. Resnick B. A bladder scan trial in geriatric rehabilitation. Rehabilitation Nursing.

1995;20(4):194-6.

34. Coombes GM, Millard RJ. The accuracy of portable ultrasound scanning in the measurement

of residual urine volume. Journal of Urology. 1994;152(6 Pt 1):2083-5.

35. Topper AK, Holliday PJ, Fernie GR. Bladder volume estimation in the elderly using a portable

ultrasound-based measurement device. J Med Eng Technol. 1993;17(3):99-103.

38 | P a g e

36. Ireton RC, Krieger JN, Cardenas DD, Williams-Burden B, Kelly E, Souci T, et al. Bladder volume

determination using a dedicated, portable ultrasound scanner. Journal of Urology.

1990;143(5):909-11.

37. Cardenas DD, Kelly E, Krieger JN, Chapman WH. Residual urine volumes in patients with

spinal cord injury: measurement with a portable ultrasound instrument. Arch Phys Med Rehabil.

1988;69(7):514-6.

38. Huang Y-H, Bih L-I, Chen S-L, Tsai S-J, Teng C-H. The accuracy of ultrasonic estimation of

bladder volume: a comparison of portable and stationary equipment. Archives of physical medicine

and rehabilitation. 2004;85(1):138-41.