Disorders of micturition Stephen P. DiBartola, DVM Department of Veterinary Clinical Sciences...
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Transcript of Disorders of micturition Stephen P. DiBartola, DVM Department of Veterinary Clinical Sciences...
Disorders of micturitionDisorders of micturition
Stephen P. DiBartola, DVMStephen P. DiBartola, DVM
Department of Veterinary Clinical SciencesDepartment of Veterinary Clinical Sciences
College of Veterinary MedicineCollege of Veterinary Medicine
Ohio State UniversityOhio State University
Columbus, OH 43210Columbus, OH 43210
The Nephronauts
Disorders of micturitionDisorders of micturitionDisorders of micturitionDisorders of micturition
Normal and abnormal Normal and abnormal micturitionmicturition
Normal and abnormal Normal and abnormal micturitionmicturition
• Normal micturition (urination)Normal micturition (urination)• Filling phaseFilling phase
• Emptying phaseEmptying phase
• IncontinenceIncontinence• Loss of voluntary control of Loss of voluntary control of
micturition (urination)micturition (urination)
Micturition: Emptying phaseMicturition: Emptying phaseMicturition: Emptying phaseMicturition: Emptying phase
Micturition: Filling phaseMicturition: Filling phaseMicturition: Filling phaseMicturition: Filling phase
Micturition: Role of Micturition: Role of somatic nervous systemsomatic nervous system
Micturition: Role of Micturition: Role of somatic nervous systemsomatic nervous system
Disorders of micturitionDisorders of micturitionDisorders of micturitionDisorders of micturition
• Non-neurogenicNon-neurogenic
• NeurogenicNeurogenic
Non-neurogenic Non-neurogenic disorders of micturitiondisorders of micturition
Non-neurogenic Non-neurogenic disorders of micturitiondisorders of micturition
• Hormone-responsive (?)Hormone-responsive (?)• Anatomic abnormalityAnatomic abnormality• Paradoxical (obstructive)Paradoxical (obstructive)• Post-prostatectomyPost-prostatectomy• Post-perineal urethrostomyPost-perineal urethrostomy• Urge incontinence with UTIUrge incontinence with UTI• Sphincter mechanism incompetenceSphincter mechanism incompetence
Hormone-responsive Hormone-responsive urinary incontinenceurinary incontinenceHormone-responsive Hormone-responsive urinary incontinenceurinary incontinence
• Estrogen-responsive in female Estrogen-responsive in female dogsdogs
• Testosterone-responsive in male Testosterone-responsive in male dogsdogs
• Same as sphincter mechanism Same as sphincter mechanism incompetence or an overlapping incompetence or an overlapping syndrome?syndrome?
Non-neurogenic Non-neurogenic disorders of micturitiondisorders of micturition
Non-neurogenic Non-neurogenic disorders of micturitiondisorders of micturition
• Anatomic abnormalityAnatomic abnormality• Ectopic ureter MOST commonEctopic ureter MOST common
• Others much less commonOthers much less common
Ectopic ureters in dogsEctopic ureters in dogsEctopic ureters in dogsEctopic ureters in dogs
• Young (< 1 year) at presentationYoung (< 1 year) at presentation• Female > MaleFemale > Male• Siberian huskies, Labrador Siberian huskies, Labrador
retrievers, Golden retrievers, retrievers, Golden retrievers, othersothers
• Unilateral (67%) or bilateral (33%)Unilateral (67%) or bilateral (33%)• Terminate in vagina or distal Terminate in vagina or distal
urethraurethra
Ectopic ureters in dogsEctopic ureters in dogsEctopic ureters in dogsEctopic ureters in dogs
• Usually diagnosed Usually diagnosed by excretory by excretory urography or urography or ultrasonographyultrasonography
• Urethrocystoscopy Urethrocystoscopy may be “gold” may be “gold” standard for standard for diagnosisdiagnosis
urethraurethra
NormalNormalureteralureteralopeningopening
Ectopic ureters in dogsEctopic ureters in dogsEctopic ureters in dogsEctopic ureters in dogs
Urethral lumenUrethral lumen
UnilateralUnilateral BilateralBilateral
Cannizzo, 2000Cannizzo, 2000
Ectopic ureters in dogsEctopic ureters in dogsEctopic ureters in dogsEctopic ureters in dogs
Fenestrations in ectopic ureters openings in Fenestrations in ectopic ureters openings in urethras of female dogs (Cannizzo, 2000)urethras of female dogs (Cannizzo, 2000)
Ectopic ureters in dogsEctopic ureters in dogsEctopic ureters in dogsEctopic ureters in dogs
• Often accompanied by other Often accompanied by other abnormalitiesabnormalities• HydroureterHydroureter• HydronephrosisHydronephrosis• Urethral sphincter mechanism Urethral sphincter mechanism
incompetenceincompetence• Bladder hypoplasiaBladder hypoplasia• Renal problems (pyelonephritis, Renal problems (pyelonephritis,
renal hypoplasia)renal hypoplasia)
Ectopic ureters in dogsEctopic ureters in dogsEctopic ureters in dogsEctopic ureters in dogs
• Surgery controls incontinence in Surgery controls incontinence in only 50% of affected dogsonly 50% of affected dogs
• Owner must be warned that many Owner must be warned that many affected dogs have coexisting affected dogs have coexisting sphincter mechanism incompetence sphincter mechanism incompetence and may remain incontinent after and may remain incontinent after surgical correctionsurgical correction
Primary sphincter mechanism Primary sphincter mechanism incompetence in dogsincompetence in dogs
Primary sphincter mechanism Primary sphincter mechanism incompetence in dogsincompetence in dogs
• Common in large breed spayed femalesCommon in large breed spayed females• Common breeds: Doberman, giant Common breeds: Doberman, giant
Schnauzer, Old English sheepdog, Schnauzer, Old English sheepdog, RottweilerRottweiler
• Maximum urethral closure pressure Maximum urethral closure pressure (MUCP) lower and functional profile (MUCP) lower and functional profile length (FPL) shorter on urethral length (FPL) shorter on urethral pressure profile (UPP) in affected dogspressure profile (UPP) in affected dogs
• Bladder neck positioned more caudally Bladder neck positioned more caudally on radiographson radiographs
Primary sphincter mechanism Primary sphincter mechanism incompetence: Role of intra-incompetence: Role of intra-
abdominal pressureabdominal pressure
Primary sphincter mechanism Primary sphincter mechanism incompetence: Role of intra-incompetence: Role of intra-
abdominal pressureabdominal pressure
• Intra-abdominal pressure Intra-abdominal pressure increases in lateral recumbencyincreases in lateral recumbency
• Increases in intra-abdominal Increases in intra-abdominal pressure cannot be transmitted pressure cannot be transmitted to bladder neck and proximal to bladder neck and proximal urethra if these structures are urethra if these structures are displaced caudallydisplaced caudally
Primary sphincter mechanism Primary sphincter mechanism incompetence: Treatmentincompetence: Treatment
Primary sphincter mechanism Primary sphincter mechanism incompetence: Treatmentincompetence: Treatment
• 90% of affected female dogs 90% of affected female dogs respond well to respond well to phenylpropanolamine (PPA)phenylpropanolamine (PPA)
• 60% respond to estrogens60% respond to estrogens
• Some require both PPA and Some require both PPA and estrogensestrogens
Refractory sphincter mechanism Refractory sphincter mechanism incompetence: Collagen injectionincompetence: Collagen injectionRefractory sphincter mechanism Refractory sphincter mechanism incompetence: Collagen injectionincompetence: Collagen injection
• 50% response rate50% response rate• Response may be improved by Response may be improved by
adding phenylpropanolamineadding phenylpropanolamine• Injections can be repeated with Injections can be repeated with
similar response ratesimilar response rate• ExpensiveExpensive• Requires technical expertiseRequires technical expertise
Refractory sphincter mechanism Refractory sphincter mechanism incompetence: Colposuspensionincompetence: ColposuspensionRefractory sphincter mechanism Refractory sphincter mechanism incompetence: Colposuspensionincompetence: Colposuspension
• Moves bladder neck cranially and Moves bladder neck cranially and lengthens urethralengthens urethra• Approximately 50% response rateApproximately 50% response rate• Response rate may be improved by Response rate may be improved by
addition of phenylpropanolamine in addition of phenylpropanolamine in some dogssome dogs• Complications: transient dysuria, Complications: transient dysuria,
suture breakdown with relapsesuture breakdown with relapse
Neurogenic urinary incontinenceNeurogenic urinary incontinenceNeurogenic urinary incontinenceNeurogenic urinary incontinence
• UMN (automatic) bladderUMN (automatic) bladder• Lesion cranial to S1-S3Lesion cranial to S1-S3
• Partial voiding (local reflex arc intact)Partial voiding (local reflex arc intact)
• High residual volumeHigh residual volume
• Difficult to express (“external” urethral Difficult to express (“external” urethral sphincter lacks UMN inhibition)sphincter lacks UMN inhibition)
• Loss of voluntary controlLoss of voluntary control
Neurogenic urinary incontinenceNeurogenic urinary incontinenceNeurogenic urinary incontinenceNeurogenic urinary incontinence
• LMN (autonomous) bladderLMN (autonomous) bladder• S1-S3 lesionS1-S3 lesion• Partial “emptying” when Partial “emptying” when
intravesical/intra-abdominal pressure intravesical/intra-abdominal pressure exceeds elasticity of urethraexceeds elasticity of urethra
• Residual volume higher than UMN Residual volume higher than UMN bladderbladder
• Easy to express manuallyEasy to express manually• Loss of voluntary controlLoss of voluntary control
Reflex dyssynergy Reflex dyssynergy (reflex dyssynergia)(reflex dyssynergia)Reflex dyssynergy Reflex dyssynergy
(reflex dyssynergia)(reflex dyssynergia)
• Detrusor contracts but Detrusor contracts but urethral muscle fails to relaxurethral muscle fails to relax
Reflex dyssynergy: a diagnosis of Reflex dyssynergy: a diagnosis of exclusionexclusion
Reflex dyssynergy: a diagnosis of Reflex dyssynergy: a diagnosis of exclusionexclusion
• Middle-aged large to giant breed Middle-aged large to giant breed male dogsmale dogs• Watch dog urinate (normal stream Watch dog urinate (normal stream
initiation then dribbling and initiation then dribbling and tenesmus)tenesmus)• Pass urinary catheter to rule out Pass urinary catheter to rule out
mechanical obstructionmechanical obstruction• Measure residual urine volumeMeasure residual urine volume• Normal: < 0.4 ml/kgNormal: < 0.4 ml/kg• Dyssynergy: Often 20 ml/kg or moreDyssynergy: Often 20 ml/kg or more
Reflex dyssynergy: TreatmentReflex dyssynergy: TreatmentReflex dyssynergy: TreatmentReflex dyssynergy: Treatment• Phenoxybenzamine followed by bethanechol Phenoxybenzamine followed by bethanechol
if necessaryif necessary• Prazosin (specific alpha-1 blocker) followed Prazosin (specific alpha-1 blocker) followed
by bethanechol if necessaryby bethanechol if necessary• Diazepam or dantrolene if suspect striated Diazepam or dantrolene if suspect striated
muscle componentmuscle component• Intermittent catheterization as needed to Intermittent catheterization as needed to
maintain low residual volumemaintain low residual volume• Complications: bladder hyporeflexia, chronic Complications: bladder hyporeflexia, chronic
UTIUTI• Can be frustrating to manageCan be frustrating to manage
Disorders of micturition: HistoryDisorders of micturition: HistoryDisorders of micturition: HistoryDisorders of micturition: History
• SignalmentSignalment• Young animals Young animals Congenital Congenital
disordersdisorders• Middle-aged, medium to large Middle-aged, medium to large
breed female dogs breed female dogs Sphincter Sphincter mechanism incompetencemechanism incompetence
Disorders of micturition: HistoryDisorders of micturition: HistoryDisorders of micturition: HistoryDisorders of micturition: History
• Differentiate loss of voluntary Differentiate loss of voluntary control from behavior change or control from behavior change or PU/PDPU/PD
• Ask about hematuria or dysuriaAsk about hematuria or dysuria
• Ask about previous trauma or Ask about previous trauma or surgerysurgery
Disorders of micturition: Disorders of micturition: Physical findingsPhysical findings
Disorders of micturition: Disorders of micturition: Physical findingsPhysical findings
• Observe perineal region in Observe perineal region in females for wetness or odorfemales for wetness or odor
• Palpate bladder, urethra and Palpate bladder, urethra and prostate in malesprostate in males
• Perform vaginal exam in femalesPerform vaginal exam in females• Perform complete neurologic Perform complete neurologic
examinationexamination
Disorders of micturition: Disorders of micturition: Neurologic examNeurologic exam
Disorders of micturition: Disorders of micturition: Neurologic examNeurologic exam
• Anal toneAnal tone
• Bulbocavernosus reflexBulbocavernosus reflex
• Perineal reflexPerineal reflex
Disorders of micturition: Disorders of micturition: Other findingsOther findings
Disorders of micturition: Disorders of micturition: Other findingsOther findings
• Observe animal urinatingObserve animal urinating
• Pass urethral catheter to rule Pass urethral catheter to rule out mechanical obstructionout mechanical obstruction
• Collect and measure residual Collect and measure residual volume (normal, < 0.4 ml/kg)volume (normal, < 0.4 ml/kg)
Disorders of micturition: Disorders of micturition: Laboratory findingsLaboratory findings
Disorders of micturition: Disorders of micturition: Laboratory findingsLaboratory findings
• UrinalysisUrinalysis
• Urine culture and sensitivityUrine culture and sensitivity
• Contrast radiographyContrast radiography• Rule out anatomic abnormalityRule out anatomic abnormality
• UltrasonographyUltrasonography
Disorders of micturitionDisorders of micturitionSpecial procedures: CystometrogramSpecial procedures: CystometrogramDisorders of micturitionDisorders of micturitionSpecial procedures: CystometrogramSpecial procedures: Cystometrogram
• Pressure-Pressure-volume volume recording of recording of bladder’s bladder’s response to response to filling with filling with fluid or COfluid or CO22
Disorders of micturitionDisorders of micturitionSpecial procedures: Urethral pressure Special procedures: Urethral pressure profileprofile
Disorders of micturitionDisorders of micturitionSpecial procedures: Urethral pressure Special procedures: Urethral pressure profileprofile
• Pressure tracing Pressure tracing of urethra as of urethra as catheter is catheter is slowly slowly withdrawn from withdrawn from bladder at bladder at constant speedconstant speed
Urethral pressure profileUrethral pressure profileUrethral pressure profileUrethral pressure profile
• Maximum urethral pressure (MUP): Maximum urethral pressure (MUP): highest pressure recorded in urethrahighest pressure recorded in urethra
• Maximum urethral closure pressure Maximum urethral closure pressure (MUCP): difference between MUP and (MUCP): difference between MUP and intravesical pressureintravesical pressure
• Functional profile length (FPL): length Functional profile length (FPL): length of urethra over which urethral pressure of urethra over which urethral pressure exceeds intravesical pressureexceeds intravesical pressure
Urethral pressure profileUrethral pressure profileUrethral pressure profileUrethral pressure profile
FPL is most consistent; MUCP more variableFPL is most consistent; MUCP more variable
FPLFPLFPLFPL
MUCPMUCPMUCPMUCP
Micturition disorders: TreatmentMicturition disorders: TreatmentMicturition disorders: TreatmentMicturition disorders: Treatment
• Neurogenic: Correct lesion if Neurogenic: Correct lesion if possiblepossible
• Anatomic: Correct lesion if Anatomic: Correct lesion if possiblepossible
• Paradoxical: Relieve obstructionParadoxical: Relieve obstruction
• Urge: Treat UTIUrge: Treat UTI
Micturition disorders: TreatmentMicturition disorders: TreatmentMicturition disorders: TreatmentMicturition disorders: Treatment
• Hormone-responsive in femalesHormone-responsive in females• Diethylstilbestrol (DES) 0.1 to 1.0 mg Diethylstilbestrol (DES) 0.1 to 1.0 mg
PO PO 3-5 days followed by 1 mg PO 3-5 days followed by 1 mg PO q7dq7d• PremarinPremarin® 20 ® 20 g/kg PO q4d or 0.6 mg g/kg PO q4d or 0.6 mg
total dose q4dtotal dose q4d• Adverse effects: estrus, perineal Adverse effects: estrus, perineal
alopecia, bone marrow suppressionalopecia, bone marrow suppression
Micturition disorders: TreatmentMicturition disorders: TreatmentMicturition disorders: TreatmentMicturition disorders: Treatment
• Adrenergic agonists (urethral Adrenergic agonists (urethral smooth muscle stimulants)smooth muscle stimulants)• EphedrineEphedrine• Nonspecific agonist: Nonspecific agonist: > > • Dogs: 25-100 mg PO q12h to q8hDogs: 25-100 mg PO q12h to q8h• Adverse effects: CNS stimulation, Adverse effects: CNS stimulation,
tachycardia, hypertensiontachycardia, hypertension• Not used much due to adverse effectsNot used much due to adverse effects
Micturition disorders: TreatmentMicturition disorders: TreatmentMicturition disorders: TreatmentMicturition disorders: Treatment
• Adrenergic agonists (urethral Adrenergic agonists (urethral smooth muscle stimulants)smooth muscle stimulants)• Phenylpropanolamine (PPA)Phenylpropanolamine (PPA)
-adrenergic agonist-adrenergic agonist• Dogs: 1.5 mg/kg PO q12h to q8hDogs: 1.5 mg/kg PO q12h to q8h• Effective in 90% of dogs with sphincter Effective in 90% of dogs with sphincter
mechanism incompetencemechanism incompetence• Less CNS stimulation than ephedrine and Less CNS stimulation than ephedrine and
no significant effect on blood pressureno significant effect on blood pressure• Off the human marketOff the human market
Micturition disorders: TreatmentMicturition disorders: TreatmentMicturition disorders: TreatmentMicturition disorders: Treatment
• Adrenergic antagonists (urethral Adrenergic antagonists (urethral smooth muscle relaxants)smooth muscle relaxants)• PhenoxybenzaminePhenoxybenzamine• Non-specific Non-specific -adrenergic antagonist-adrenergic antagonist• 0.25 to 0.5 mg/kg q12h to q8h0.25 to 0.5 mg/kg q12h to q8h• Relaxes urethral smooth muscleRelaxes urethral smooth muscle• Adverse effect: hypotensionAdverse effect: hypotension• Used for functional outlet obstruction Used for functional outlet obstruction
(including reflex dyssynergy)(including reflex dyssynergy)
Micturition disorders: TreatmentMicturition disorders: TreatmentMicturition disorders: TreatmentMicturition disorders: Treatment
• Adrenergic antagonists (urethral Adrenergic antagonists (urethral smooth muscle relaxants)smooth muscle relaxants)• PrazosinPrazosin• Specific Specific -1 adrenergic antagonist-1 adrenergic antagonist• 0.1 mg/kg divided q8h0.1 mg/kg divided q8h• Relaxes urethral smooth muscleRelaxes urethral smooth muscle• Adverse effect: hypotensionAdverse effect: hypotension• Used for functional outlet obstruction Used for functional outlet obstruction
(including reflex dyssynergy)(including reflex dyssynergy)
Micturition disorders: TreatmentMicturition disorders: TreatmentMicturition disorders: TreatmentMicturition disorders: Treatment
• Adrenergic antagonists (urethral Adrenergic antagonists (urethral smooth muscle relaxants)smooth muscle relaxants)• AcepromazineAcepromazine• Phenothiazine with Phenothiazine with -adrenergic -adrenergic
antagonist effectsantagonist effects• 0.2 mg/kg SQ q12h or 1.25 mg total 0.2 mg/kg SQ q12h or 1.25 mg total
dose PO q24h for post-obstructive dose PO q24h for post-obstructive urethral spasm in catsurethral spasm in cats• Relaxes urethral smooth muscleRelaxes urethral smooth muscle• Adverse effect: hypotensionAdverse effect: hypotension
Micturition disorders: TreatmentMicturition disorders: TreatmentMicturition disorders: TreatmentMicturition disorders: Treatment
• Other non-specific smooth muscle Other non-specific smooth muscle relaxants used for detrusor relaxants used for detrusor hyperactivityhyperactivity• PropanthelinePropantheline• OxybutyninOxybutynin• FlavoxateFlavoxate• DicyclomineDicyclomine
Micturition disorders: TreatmentMicturition disorders: TreatmentSmooth muscle stimulantsSmooth muscle stimulantsMicturition disorders: TreatmentMicturition disorders: TreatmentSmooth muscle stimulantsSmooth muscle stimulants
• BethanecholBethanechol• Parasympathomimetic with primarily Parasympathomimetic with primarily
muscarinic effectsmuscarinic effects• Dogs: 5-15 mg PO q8hDogs: 5-15 mg PO q8h• Cats: 1.25-5 mg PO q8hCats: 1.25-5 mg PO q8h• Adverse effects: Anorexia, salivation, Adverse effects: Anorexia, salivation,
lacrimation, abdominal cramping, lacrimation, abdominal cramping, vomiting, diarrheavomiting, diarrhea• Used for detrusor hypoactivity, used in Used for detrusor hypoactivity, used in
conjunction with conjunction with -antagonist in reflex -antagonist in reflex dyssynergydyssynergy
Micturition disorders: TreatmentMicturition disorders: TreatmentMicturition disorders: TreatmentMicturition disorders: Treatment
• Striated muscle relaxantsStriated muscle relaxants• DiazepamDiazepam• Used to relax urethral striated muscleUsed to relax urethral striated muscle• Dog: 2-10 mg PO q8hDog: 2-10 mg PO q8h• Cat: 1-2 mg PO q8hCat: 1-2 mg PO q8h• CAUTION IN CATS: Hepatotoxicity may CAUTION IN CATS: Hepatotoxicity may
be observed when administered orallybe observed when administered orally• May have limited effect on feline urethral May have limited effect on feline urethral
striated musclestriated muscle
Micturition disorders: TreatmentMicturition disorders: TreatmentMicturition disorders: TreatmentMicturition disorders: Treatment
• Skeletal muscle relaxantsSkeletal muscle relaxants• DantroleneDantrolene• Direct-acting striated muscle Direct-acting striated muscle
relaxantrelaxant• Used for urethral striated muscle Used for urethral striated muscle
spasmspasm• Dog: 1-5 mg/kg PO q12h to q8hDog: 1-5 mg/kg PO q12h to q8h• Adverse effects: HepatotoxicityAdverse effects: Hepatotoxicity