bju3_feb2006

8/2/2019 BJU3_feb2006

http://slidepdf.com/reader/full/bju3feb2006 1/5

2 3 8 © 20 05 BJ U IN TE RN AT IO NA L | 97 , 23 8– 24 2 | doi:10.1111/j .1464-410X.2006.05884.x

TEACHING ABOUT VOIDING DISORDERSSTEERS and GRAY

A simple method for teaching about voiding disordersWILLIAM D. STEERS and MIKEL GRAY*Department of Urology and *School of Nursing, University of Virginia Charlottesville, VA, USA

Accepted for publication 28 July 2005

schemes based on the vague term ‘neurogenicbladder’ have been promulgated, but they aredifficult to apply in practice because they failto adequately account for differences in LUTfunction despite a common neurologicaldiagnosis, and they fail to describe patientswith more than one pathology. In addition,they do not uniformly inform therapeuticdecisions, particularly in patients withfunctional limitations that restrict treatmentoptions [5]. A more recent scheme based onurodynamic findings and symptoms

originated within a nomenclature committeecomposed of experts of the ICS. This scheme isbased on a description of LUTS, which aretypically divided into storage and voidingsymptoms [6]. While this type of taxonomy isuseful in describing the various symptomsassociated with LUT disorders, it fails todifferentiate the underlying causes of thedisorder or elucidate appropriate treatment,and it is difficult to comprehend bygeneralists unfamiliar with urodynamictesting.

An objective classification scheme based on aprognosis, similar to cancer staging orcardiovascular risks, would be extremelyuseful in this field. Unfortunately, the naturalhistory of many disorders of the LUT isunknown and evidence-based therapiesderived from prospective randomized trialsare often lacking. Therefore, a simple andreliable scheme for teaching students andgeneralists is needed, as these professionalsare likely to encounter voiding disorders intheir clinical practice.

THE TWO-BY-TWO GRID METHOD

Based on teaching medical students, residentsand non-urologists for over a decade, abinomial-type system was developed thatprovides a simple conceptualization of pathophysiology and treatment strategies fordisorders of the LUT. A proposed advantage of such as system is its ability to summarizepathophysiology, diagnostic methods andtreatments on three to five figures in a formatthat can be readily updated when newknowledge becomes available. While

highlighting functional goals, this gridmethod provides an easy way to visualizecombined therapies for complex disorders.

Figure 1 provides the conceptual frameworkfor this classification scheme; a two-by-twogrid with column headings for two functionalunits is used to characterize LUT dysfunctionregardless of the underlying disease. Theheading ‘Bladder’ indicates the detrusormuscle and visco-elastic properties of thebladder wall. The heading ‘Outlet’ indicates

the bladder neck, urethra and urethralsphincter mechanism. The pelvic floormusculature and ligamentous supportinfluence the outlet and could be added tothis scheme.

Under the ‘Bladder’ heading two pathologicalpossibilities exist, i.e. overactive orunderactive. LUTS associated with overactivedysfunction include frequent urination (morethan eight episodes/24 h), nocturia (three ormore episodes per night), urgency (a suddenand strong desire to urinate that is not easilydeferred) and urge urinary incontinence(urine loss associated with urgency). Thesesymptoms have been referred to as ‘irritative’but more recently they were termed the‘overactive bladder’ [6]. LUTS associated withan underactive bladder include a diminishedor poor force of urinary stream, intermittencyof stream, hesitancy, feelings of incompletebladder emptying, and terminal dribble. Twopathological possibilities are placed beneaththe ‘Outlet’ heading, i.e. increased resistanceor reduced resistance. Increased resistanceindicates BOO and produces LUTS similar tothose seen with an underactive detrusor. They

include poor force of urinary stream,intermittency or hesitancy, feelings of incomplete bladder emptying and terminaldribble. Further diagnostic testing is neededto clearly differentiate these headings.Reduced urethral resistance is associated withthe symptom of stress urinary incontinence,defined as urine loss associated with physicalactivity, coughing or sneezing.

There are 12 known combinations that explainall described voiding disorders. Table 1lists these classical possibilities with

KEYWORDS

lower urinary tract symptoms, classificationschema, urinary incontinence

INTRODUCTION

Several terms have been used to describefunctional disorders of the LUT, includingurinary incontinence, neurogenic bladder,overactive bladder dysfunction, BPH,

interstitial cystitis, and chronic prostatitis(male pelvic pain syndrome). Patients withLUT disorders seek care from a wide range of healthcare providers, including nurses,geriatricians, gynaecologists, urologists,rehabilitation medicine specialists, familyphysicians and internists, and the collectiveannual cost of managing them exceedsUS$36 billion [1–3]. However, efforts toeducate clinicians and students about thesedisorders have been hindered by variability inthe nomenclature used to define theseconditions; overlap among diagnoses; a lackof distinctive classifications allowing theclinician to readily classify LUT disorders; andthe myriad of available treatments. Moreover,patient symptoms and associated bother donot directly correlate with objective signs (padtesting, bladder diaries) or the underlyingpathophysiological mechanisms as measuredby urodynamic testing. For example, there is apoor correlation between subjectivesymptoms associated with involuntary urineloss (urge vs stress) and the cause of incontinence [4].

Several didactic classification schemes have

attempted to characterize LUT disorders butnone has proved entirely adequate. Forexample, a urodynamic-based scheme dividesLUT dysfunction into four readily understoodclassifications: (i) failure to store urinebecause of the bladder; (ii) failure to storeurine because of the outlet; (iii) failure toempty urine because of the bladder; or (iv) orfailure to failure to empty urine because of the outlet. However, clinical application islimited because it requires complexurodynamic testing to accurately classifyindividual patients. Many classification

8/2/2019 BJU3_feb2006


T E A C H I N G A B O U T V O I D I N G D I S O R D E R S

©

2 0 0 5 B J U I N T E R N A T I O N A L

2 3 9

corresponding LUTS, urodynamic findings andcommon clinical diagnoses. Allowancesneed to be made for connective tissueabnormalities of the bladder that causereduced compliance (distensibility) therebycreating a potentially high intravesicalpressures or the urodynamic finding of a highdetrusor leak pressure. These conditions canbe placed in the ‘overactive’ quadrant.Reduced compliance can be functionallyenvisioned as an overactive bladder because itcan contribute to upper tract deteriorationand/or urinary incontinence. A condition suchas a noncompliant, fixed urethra that fails torespond to increases in intravesical pressurecan be placed in the quadrant labelled‘reduced resistance’ as it can lead to urinaryincontinence. Some patients present withobstruction and a fibrotic urethra at the levelof the intrinsic sphincter mechanism,accounting for the paradoxical combination

of increased plus reduced urethral resistance.

In addition to categorizing patients by clinicalpresentation, each of the four quadrants canbe used to list underlying pathophysiologicalmechanisms and treatment options. Figure 2outlines the two major causes of anoveractive or underactive bladder, i.e.myogenic or neurogenic dysfunction.Examples of neurogenic disorders includespinal cord injury, myelodysplasia, Parkinson’sdisease and multiple sclerosis. Theseneurological disorders may give rise to an

overactive bladder, and cause urinaryfrequency and urge incontinence. Changes inthe bladder smooth muscle, termed thedetrusor, can also be caused by myogenicchanges that arise from obstruction,ischaemia or injury. Certain disorders such asdiabetes mellitus trigger changes in nervesand muscle that can lead to both anoveractive and underactive bladder.

However, categorizing LUT disorders solelybased on myogenic or neurogenic causes failsto incorporate recent concepts whichrecognize that urothelium, interstitial cellsand connective tissue also influence bladderactivity, and that cell-cell interactions occur.For didactic purposes these more detailedcauses could be placed in the two bladderquadrants for a more advanced audience. Butfor generalists such distinctions are irrelevantbecause diagnostic tests and therapies haveyet to be developed relying on thesemechanisms. For example, antimuscarinicagents are the drugs of choice for anoveractive bladder, regardless of cause.

With regard to the outlet, increased resistance

can be due to anatomical abnormalities orfunctional disorders. Anatomical conditionsinclude urethral strictures. The functionaldisorders of detrusor sphincter dyssynergiadue to spinal pathology and BPH can fallunder both rubrics. Reduced resistance can bedue to urethral hypermobility or intrinsicsphincter insufficiency (Fig. 3).

To distinguish myogenic from neurogeniccauses for overactive or underactive bladder,a history, physical examination andurodynamics are usually required. The

differential diagnosis of anatomical vsfunctional causes of ‘increased resistance’requires urodynamic testing, radiographicimaging studies of the LUT or cystoscopy.Differentiation of reduced urethral resistancecaused by urethral hypermobility or intrinsicsphincter deficiency is typically based onphysical examination, a Q-tip test, video-urodynamic testing or an imaging study of the pelvic floor such as MRI. Urodynamics isrequired to determine an abdominal or

Valsalva leak-point pressure to diagnoseintrinsic sphincter deficiency.

THERAPEUTIC DECISION MAKING

To classify patients into any given quadrantbased solely on symptoms is difficult becausethey are not reliable in identifying theunderlying pathophysiology. For example, thecomplaint of stress incontinence in a 45-year-old woman could be due to an underactivebladder with high residual urine and overflow,or cough-induced involuntary bladdercontractions (overactive bladder). Althoughidentifying her dysfunction as reduced

resistance seems reasonable it is inaccurate. Amore accurate categorization requires thecombination of measuring residual urine andurodynamics. In another example, a 60-year-old man complaining of a slow urinary streamwith a residual urine of 300 mL may becategorized as having increased resistancedue to BPH (anatomical + functional).However, it is also possible that the symptomsderive from an underactive bladder.Urodynamic testing would determine whetherthere is detrusor hypocontractility orobstruction. Despite the usefulness of

FIG. 1. Categorization of disorders of the LUT by

bladder and outlet (bladder neck, urethra, external

urethral sphincter). Overactive +

increased

resistance corresponds to failure to empty or retain.

Underactive +

reduced resistance corresponds to

failure to store, or to urinary incontinence

Bladder Outlet

Overactive*

Underactive

Reduced resistance**

Increased resistance

*Includes poor bladder compliance and highdetrusor leak pressures**Includes pipestem, rigid urethra

FIG. 2.

The pathogenesis of overactive

(including reduced bladder

compliance) and underactive

bladder disorders.

Overactive Underactive

Myogenic

Neurogenic(Afferents,efferents, CNS)

Neurogenic(Afferents,CNS)

MyogenicUrothelialConnectivetissue

• History

• Examination

• Urodynamics

FIG. 3.

Pathophysiology of increased and

reduced (fixed) outlet resistance.

Increased resistance Reduced resistance

Intrinsic sphincterdeficiency

HypermobilityAnatomic

Functional • Urodynamics

Cystoscopyimaging

8/2/2019 BJU3_feb2006


S T E E R S a n d G R A Y

2 4 0

©


TABLE 1 Categories of bladder/outlet disorders with associated LUTS, urodynamic findings or clinical diagnoses

Pathophysiology LUTS/urodynamic findings/clinical diagnoses or examples

Overactive

LUTS

: urgency, voiding frequency, urgency ±

urge incontinence

Urodynamic

: detrusor overactivity

Clinical

: Overactive bladder, urge incontinenceUnderactive

LUTS

: poor force of urinary stream, intermittency, hesitancy, feelings of incomplete bladder emptying, terminal dribble

Urodynamic

: prolonged or intermittent flow pattern with poor detrusor contraction strength (low amplitude, poor duration),

increased urinary residual volume

Clinical

: Acontractile detrusor, atony of bladder


LUTS

: poor force of urinary stream, intermittency, hesitancy, feelings of incomplete bladder emptying, terminal dribble

Urodynamic

: prolonged or intermittent flow pattern with elevated detrusor contraction pressures (increased urethral resistance)

±


Clinical

: Bladder neck dyssynergia or contracture, prostate enlargement, detrusor sphincter dyssynergia causing functional

obstruction, urethral stricture

Reduced resistance

LUTS

: stress incontinence (urine loss with physical exertion, coughing and sneezing)

Urodynamic

: urine loss with increased abdominal pressure

Clinical

: stress urinary incontinence, urethral hypermobility, intrinsic sphincter deficiency

Overactive

+

increased resistance

LUTS


urge incontinence with poor force of urinary stream, intermittency, hesitancy,

feelings of incomplete bladder emptying, terminal dribble

Urodynamic

: Detrusor overactivity, prolonged or intermittent flow pattern with increased urethral resistance ±

increased urinary

residual volume

Clinical

: BPH with overactive bladder

+

reduced resistance

LUTS


urge incontinence, stress incontinence

Urodynamic

: urine loss with detrusor overactivity and with increased abdominal pressures

Clinical

: Mixed urinary incontinence

Overactive +

underactive

LUTS

: urgency (first urge may occur after onset of urge incontinence) voiding frequency, urge incontinence with poor force of

stream, intermittency

Urodynamic

: Detrusor overactivity with poor contraction strength and elevated urinary residual volumes

Clinical

: Detrusor hyperactivity with insufficient contractility

Increased resistance +

LUTS

: stress UI combined with poor force of stream, intermittency

reduced resistance

Urodynamic

: urine loss with increased abdominal pressure, prolonged or intermittent flow pattern with increased urethralresistance ±


Clinical

: Post-prostatectomy stricture and stress incontinence

Underactive:

+

reduced resistance

LUTS

: stress incontinence with poor force of urinary stream, intermittency, hesitancy, feelings of incomplete bladder emptying,

terminal dribble

Urodynamic:

urine loss with increased abdominal pressure and prolonged or intermittent flow pattern with poor detrusor

contraction strength (low amplitude, poor duration), increased urinary residual volume

Clinical

: sacral agenesis with residual urine and stress incontinence

+


LUTS

: poor force of urinary stream, intermittency, hesitancy, feelings of incomplete bladder emptying, terminaldribble

Urodynamic

: prolonged or intermittent flow pattern with poor detrusor contraction strength (low amplitude, poor duration),

increased urethral resistance ±


Clinical

: urethral stricture or prostate enlargement with decompensation of detrusor muscle

+


LUTS

: dribbling stress incontinence with poor force of urinary stream, intermittency, hesitancy, feelings of incomplete bladder

emptying, terminal dribbleand reduced resistance

Urodynamic

: prolonged or intermittent flow pattern with poor detrusor contraction strength (low amplitude, poor duration) and

evidence of bladder outlet obstruction and increased urinary residual volume

Clinical

: Chronic bladder neck contracture after prostatectomy with stress incontinence and residual urine

Overactive

+

reduced resistance

+


+

underactive

LUTS


urge incontinence, stress incontinence, poor force of urinary stream, intermittency,

hesitancy, feelings of incomplete bladder emptying, terminal dribble

Urodynamic

: detrusor overactivity, urine loss with increased abdominal pressures, low amplitude detrusor contraction with

increased urethral resistance

Clinical

: Mixed incontinence after retropubic sling with chronic obstruction and hypocontractile bladder

8/2/2019 BJU3_feb2006


T E A C H I N G A B O U T V O I D I N G D I S O R D E R S

©


2 4 1

urodynamics to determine thepathophysiology and explain the aetiology of symptoms, this invasive testing is notmandatory for managing patients. Empiricaltherapy is often the most cost-effective initialapproach. In the first case a short course of treatment using pelvic muscle exercises couldbe initiated in the incontinent patient. The

man with presumed BPH can be tried on anα-adrenergic antagonist without urodynamictesting, if close surveillance is maintained.Indeed, early guidelines for urinaryincontinence did not recommend urodynamicevaluation for initial evaluation ormanagement of BPH [7,8]. Failure to respondto medical therapy would trigger a referral to

a specialist for further evaluation. In general,the more invasive the treatment, irreversiblethe therapy, or higher the risk, the moreexperts recommend a urodynamic evaluation.

LUTS associated with more poorly understoodconditions can also be characterized in thistaxonomy. For example, interstitial cystitisand male pelvic pain syndromes aredebilitating conditions characterized byurinary frequency and pain [9,10]. Both maybe associated with high-tone pelvic floormuscle dysfunction or increased urethralresistance, leading to reduced urinary streamor difficulty urinating, and would be classifiedas overactive with or without increasedresistance of the outlet.

Figures 4, 5 and 6 outline some therapeutic

methods that can be used to treat patients. Anadvantage of this simple scheme is the ease of visualizing combined therapies for patientswith two types of pathology. The optimumchoice of therapy is dictated by bothersomesymptoms, risk/benefit or prognosis. Forexample, a 35-year-old woman with multiplesclerosis and urge incontinence may also haverecurrent UTIs. Evaluation reveals a residualurine of 250 mL from detrusor sphincterdyssynergia and neurogenic detrusoroveractivity. She would be categorized asoveractive+ increased resistance. Fig. 5 showsthat a rational pharmacological therapyfor these two conditions could be thecombination of an antimuscarinic and anα-adrenergic blocker, or botulinum toxininjection into the external urethral sphincter.Another example would be an 80-year-oldwoman with mixed stress and urgeincontinence. Pelvic floor muscle training maybe instituted to increase urethral resistanceand alleviate overactive bladder symptoms,but if this strategy fails further diagnostictesting such as urodynamics can be used. If urodynamic testing revealed detrusoroveractivity and intrinsic sphincter deficiency,

combined therapy, consisting of anantimuscarinic and periurethral bulkingagent, could be tried. If these conservativemeasures fail, more invasive therapy such as asuburethral sling procedure may bewarranted. Thus taxonomy can be used toguide clinicians in staged decision-making.

THERAPIES

The conceptual framework we propose forclassifying LUT disorders can be expanded to

FIG. 4.

Categories of treatment of

bladder and outlet disorders. CIC,

clean intermittent

catheterization.

Bladder Outlet

Reduced resistance

• Bulking• Surgery


• Behavioural• Drug

• Minimal invasive/?neuromodulation• Surgery

Overactive

• Behavioural

• Drug• Neuromodulation• Surgery

Underactive

• CIC• Surgery

FIG. 5.

Pharmacological treatments of

bladder and outlet disorders.

Bladder Outlet

Reduced resistance

• Alpha agonist• Estrogen• Tricyclic• Duloxetine


• Alpha antagonists

• 5 alpha reductase inhibitors• Botulinum toxin

Overactive

• Anticholinergics• Smooth musclerelaxants• Tricyclics• Investigational

Underactive

• Bethanechol

FIG. 6.

Invasive or surgical treatments of

bladder and outlet disorders.

Therapies can be combined in

boxes of two or more disorders.

Bladder Outlet

Reduced resistance

• Bulking agent• AUS• Retropubic

susp/slings• Closure of bladder neck


• Minimally invasive• Urethrolysis/VIU/sphincterotomy• TURP/SP prost

Overactive

• Neurolysis• Augmentationcysto• Divert

Underactive

• Chimney• Mitrofanoff • Divert• Myoplasty

8/2/2019 BJU3_feb2006


S T E E R S a n d G R A Y

2 4 2

©


show where tools for symptom or quality-of-life (QoL) assessment fit in the management of patients (Figs 7, 8). Validated questionnairesfor BPH, e.g. the IPSS or Danish ProstateSymptom Score, could be listed under‘increased resistance’, recognizing that toolsare also designed to detect LUTS associatedwith overactive bladder function [11]. Variousadditional instruments, including theIncontinence Impact Questionnaires,Urogenital Distress Inventory, King’s HealthQuestionnaire, Michigan Epidemiological

Survey Assessment (or Overactive BladderScreening Questionnaire) can be used toidentify LUTS associated with ‘reducedresistance’, ‘overactive’ or a combination of these quadrants, resulting in stress urinaryincontinence [12].

The taxonomy we propose characterizes LUTdisorders into only four basic categories,

allowing binomial combinations, simplifiestherapeutic planning and conceptualizationof LUT disorders for the generalist. Theadvantages of this conceptual framework areits simplicity, clarity, expandability andthoroughness in explaining many commonvoiding disorders.

CONFLICT OF INTEREST

None declared.

REFERENCES

1 Calhoun EA, McNaughton Collins M,

Pontari MA et al. Chronic Prostatitis

Collaborative Research Network. Theeconomic impact of chronic prostatitis.Arch Intern Med 2004; 164: 1231–6

2 Hu TW, Wagner TH, Bentkover JD,

Leblanc K, Zhou SZ, Hunt T. Costs of urinary incontinence and overactivebladder in the United States: acomparative study. Urology 2004; 63:461–5

3 Smith MD, McGhan WF. The prostate’seconomic squeeze. Bus Health 1997; 15:40, 42

4 Gray M, McClain R, Peruggia M, Patrie

J, Steers WD. A model for predictingmotor urge urinary incontinence. Nurs

Res 2001; 50: 116–225 Fowler CJ, O’Malley KJ. Investigation

and management of neurogenic bladderdysfunction. J Neurol, NeurosurgPsychiatry 2003; 74 (Suppl. 4): iv27–iv31

6 Abrams P, Cardozo L, Fall M et al. Thestandardization of terminology of lower

urinary tract function: report from theStandardization Sub-committee of theInternational Continence Society. Am J Obstet Gynecol 2002; 187: 116–26

7 McConnell JD, Barry MJ, Bruskewitz RC

et al. Clinical Practice Guideline: BenignProstatic Hyperplasia. AHCPR Publicationno. 94–0582. Rockville, MD: Departmentof Health & Human Services, 1994

8 Roehrborn CG, McConnell JD, Barrie MJ

et al. Guideline on the management of benign prostatic hyperplasia. Baltimore,MD: American Urologic Association, 2003

9 Nordling J. Interstitial cystitis: howshould we diagnose it and treat it in2004? Curr Opin Urol 2004; 14: 323–7

10 Pontari MA, Ruggieri MR. Mechanismsin prostatitis/chronic pelvic painsyndrome. J Urol 2004; 172: 839–45

11 O’Leary M. The importance of standardisation and validation of symptom scores and quality of life: theurologist’s point of view. Eur Urol 1997;32 (Suppl. 2): 48–9

12 Graham CW, Dmochowski RR.

Questionnaires for women with urinarysymptoms. Neurourol Urodynam 2002;

21: 473–81

Correspondence: William D. Steers,Department of Urology, Box 800422,University of Virginia, Charlottesville, VA22908, USA.e-mail: [email protected]

Abbreviations: QoL, quality of life.

FIG. 7.

Symptom scoring and QoL

instruments used for voiding

disorders attributed to LUTS from

BPH causing increased outlet

resistance.

Bladder Outlet

Overactive*

UnderactiveReducedresistance

AUA-7/ IPSSDAN-PSSICSmale

FIG. 8.

Symptom scoring and QoL instruments for urinary

incontinence that may arise from

overactive bladder or reduced

outlet resistance.

Bladder Outlet

IIQ, IIQ-7UDI, UDI-6King’s Health QuestDI scoreMESABristol female LUTQuestOAN V8

UnderactiveReducedresistance

Increasedresistance

bju3_feb2006

Documents