Urodynamic effects of intravesical instillation of atropine and phentolamine in patients with detrusor hyperactivity

Pharmacotherapy for Pediatric Neurogenic Bladder

Neurogenic bladder (NB) is a nonspecific term that may describe conditions ranging from areflectic noncontractile bladder to detrusor overactivity. The most common cause of NB in children is the presence of dysraphic malformations. Urodynamic evaluations make it possible to describe bladder dysfunctions and to plan a therapeutic strategy for each patient. In a child with NB there are two major dangerous functional problems seen in urodynamic investigations: high intravesical pressure in the storage phase and high pressure during urination. The basic goals of urologic treatment for a child with NB are the protection of the urinary tract from complications and improvement of continence. Treatment for a child with NB is usually conservative, and focuses on achieving safe bladder pressures during storage with reliable emptying, via voiding or catheterization. The two most important forms of conservative treatment are clean intermittent catheterization and pharmacological treatment of functional disorders. Some drugs are used in the treatment of functional disorders in children with NB, but none of the drugs are officially approved for small children and babies.

Radiofrequency sacral rhizotomy for the management of intolerable neurogenic bladder in spinal cord injured patients

Objective

To investigate the effect of radiofrequency (RF) sacral rhizotomy of the intolerable neurogenic bladder in spinal cord injured patients.

Method

Percutaneous RF sacral rhizotomy was performed on 12 spinal cord injured patients who had neurogenic bladder manifested with urinary incontinence resisted to an oral and intravesical anticholinergic instillation treatment. Various combinations of S2, S3, and S4 RF rhizotomies were performed. The urodynamic study (UDS) was performed 1 week before RF rhizotomy. The voiding cystourethrogram (VCUG) and voiding diaries were compared 1 week before and 4 weeks after therapy. Total volume of daily urinary incontinence (ml/day) and clean intermittent catheterization (ml/time) volume of each time were also monitored.

Results

After RF sacral rhizotomy, bladder capacity increased in 9 patients and the amount of daily urinary incontinence decreased in 11 patients. The mean maximal bladder capacity increased from 292.5 to 383.3 ml (p<0.05) and mean daily incontinent volume decreased from 255 to 65 ml (p<0.05). Bladder trabeculation and vesicoureteral reflux findings did not change 4 weeks after therapy.

Conclusion

This study revealed that RF sacral rhizotomy was an effective method for neurogenic bladder with uncontrolled incontinence using conventional therapy among spinal cord injured patients.

Spontaneous activity and electrical coupling in human detrusor smooth muscle: implications for detrusor overactivity?

Large uncontrollable detrusor contractions, decreased compliance that increases luminal pressures during filling, and detrusor underactivity are all examples of abnormal bladder function. Studies of the nervous control of lower urinary tract function and measurement of the cellular properties of the component tissues of the bladder wall have been performed to deepen our knowledge of these problems. The resultant data have suggested that lower urinary tract smooth muscle should not be regarded solely as a collection of independent cellular contractile units that are each activated by separate neural inputs, but also as a syncytium of cells. Although this syncytial arrangement may not be as well developed as in other tissues, it should impose a new layer of activity that will affect overall bladder function. Recent studies have addressed this issue through investigation of spontaneous contractile activity, the cellular basis of syncytial function, and their normal and abnormal functional consequences. The results suggest that individual detrusor cells possess membrane properties that may lead to spontaneous activity fluctuations, which can affect adjacent cells and, thus, produce multicellular aberrant responses. It remains unclear whether these responses manifest themselves as dysfunctional activity in the whole bladder defects because the extent of local multicellular abnormalities is not known at present. The data do imply that myogenic defects can contribute to abnormal bladder function and, thus, suggest several new targeted drug models that should be explored.

Lidocaine cystometry in the diagnosis of bladder overactivity

The effect of intravesical lidocaine was studied in a group of patients with symptoms of urinary urgency with or without incontinence. Provocative water cystometry failed to demonstrate signs of unstable detrusor but all patients presented a continuous, steep rise of detrusor pressure at the end phase of filling. Repeat cystometry was performed after the bladder had been treated with 3 g lidocaine intravesically for 20 minutes. In the majority of patients, no change in configuration of the cystometrogram was noted. In a group of patients, a decrease of detrusor pressure occurred and there was also an influence on phasic bladder contractions. In three patients, phasic detrusor contractions developed after lidocaine. Thus, intravesical lidocaine seems to be a useful tool to increase the precision of the urodynamic diagnosis in bladder overactivity.

The effects of intravesical lidocaine on bladder dynamics of children with myelomeningocele

PURPOSE

Other studies have suggested that intravesical lidocaine may temporarily improve bladder dynamics but details of these effects and their application to children have not been examined. We evaluated the effects of intravesical lidocaine on bladder urodynamics of children with myelomeningocele and tried to correlate these effects with subsequent clinical response to oral oxybutynin.

MATERIALS AND METHODS

Charts of children with myelomeningocele who had undergone urodynamic examinations from 1992 to 1998 were reviewed retrospectively. In children with uninhibited contractions or poor compliance 150 to 300 mg. lidocaine were instilled for 8 minutes and cystometry was repeated. Changes in bladder capacity and compliance, number of uninhibited contractions and bladder volume at which pressure of 40 cm. H2O was reached were recorded before and after the lidocaine instillation. Clinical response to subsequent treatment with oral oxybutynin was assessed from chart review.

RESULTS

A total of 48 urodynamic studies in 22 girls and 20 boys with a mean age plus or minus standard deviation of 8.3 +/- 5.7 years and myelomeningocele were evaluable. After instillation of lidocaine, urodynamics showed increased bladder capacity in 70.8% of studies (34 of 48), with an average increase in volume of 66% (p <0.05). No change or decreased bladder capacity occurred in 29.2% of studies. Bladder compliance improved in 61.7% of the studies (29 of 47, p <0.05) and worsened in 38.3%. Bladder volume at which the pressure of 40 cm. H2O was reached increased in 77.8% of studies (14 of 18, p <0.05). After lidocaine the number of uninhibited contractions decreased by 3.2 in 56.8% of studies (21 of 37, p <0.05). Correlation of lidocaine induced changes in bladder capacity, compliance and number of uninhibited contractions with improvement on oral oxybutynin was 70.6%, 64.3% and 66.7%, respectively.

CONCLUSIONS

Intravesical lidocaine can improve bladder capacity and compliance and decrease the number of uninhibited contractions in many children with neurogenic bladder caused by myelomeningocele. These observations suggest that intravesical lidocaine has effects on the neurogenic bladder that improve bladder dynamics. Although intravesical lidocaine testing may not reliably predict clinical response to oral oxybutynin at the prescribed dosages, a possible therapeutic role for intravesical lidocaine or similar agents should be explored further.

The effects of intravesical lidocaine on bladder dynamics of children with myelomeningocele

PURPOSE

Other studies have suggested that intravesical lidocaine may temporarily improve bladder dynamics but details of these effects and their application to children have not been examined. We evaluated the effects of intravesical lidocaine on bladder urodynamics of children with myelomeningocele and tried to correlate these effects with subsequent clinical response to oral oxybutynin.

MATERIALS AND METHODS

Charts of children with myelomeningocele who had undergone urodynamic examinations from 1992 to 1998 were reviewed retrospectively. In children with uninhibited contractions or poor compliance 150 to 300 mg. lidocaine were instilled for 8 minutes and cystometry was repeated. Changes in bladder capacity and compliance, number of uninhibited contractions and bladder volume at which pressure of 40 cm. H2O was reached were recorded before and after the lidocaine instillation. Clinical response to subsequent treatment with oral oxybutynin was assessed from chart review.

RESULTS

A total of 48 urodynamic studies in 22 girls and 20 boys with a mean age plus or minus standard deviation of 8.3 +/- 5.7 years and myelomeningocele were evaluable. After instillation of lidocaine, urodynamics showed increased bladder capacity in 70.8% of studies (34 of 48), with an average increase in volume of 66% (p <0.05). No change or decreased bladder capacity occurred in 29.2% of studies. Bladder compliance improved in 61.7% of the studies (29 of 47, p <0.05) and worsened in 38.3%. Bladder volume at which the pressure of 40 cm. H2O was reached increased in 77.8% of studies (14 of 18, p <0.05). After lidocaine the number of uninhibited contractions decreased by 3.2 in 56.8% of studies (21 of 37, p <0.05). Correlation of lidocaine induced changes in bladder capacity, compliance and number of uninhibited contractions with improvement on oral oxybutynin was 70.6%, 64.3% and 66.7%, respectively.

CONCLUSIONS

Intravesical lidocaine can improve bladder capacity and compliance and decrease the number of uninhibited contractions in many children with neurogenic bladder caused by myelomeningocele. These observations suggest that intravesical lidocaine has effects on the neurogenic bladder that improve bladder dynamics. Although intravesical lidocaine testing may not reliably predict clinical response to oral oxybutynin at the prescribed dosages, a possible therapeutic role for intravesical lidocaine or similar agents should be explored further.

Drug therapy for urinary incontinence

Drugs used for treatment of urinary incontinence may act on the central nervous system (CNS) or peripherally. Few drugs with a defined CNS site of action are available for treatment of urine storage disorders; most of those currently used have a peripheral site of action. To treat bladder overactivity associated with urgency and urge incontinence, antimuscarinic drugs, alpha-adrenoceptor antagonists, beta-adrenoceptor agonists, prostaglandin synthesis inhibitors, and several other agents most often developed for non-urological indications, are employed. Current treatment is based on the use of antimuscarinic drugs, and oxybutynin is, despite a high incidence of side-effects, the gold standard. Pharmacological treatment of stress incontinence has had limited success, and only alpha-adrenoceptor agonists, with and without combination with oestrogens have had a documented effect. New drugs, specifically directed at treatment of urine storage disorders, are desirable.

Intravesical neuromodulatory drugs: capsaicin and resiniferatoxin to treat the overactive bladder

Current pharmacologic treatment of the overactive bladder relies on anticholinergic drugs. However, these drugs often have troublesome side effects and frequently are given in doses insufficient to restore continence in patients with detrusor instability. We present the background and basic and clinical research dealing with intravesical instillation of capsaicin and resinfferatoxin as treatments for the overactive bladder. Capsaicin is the main pungent ingredient in "hot" peppers of the genus Capsicum. It is a specific neurotoxin that desensitizes C-fiber afferent neurons, which may be responsible for the signals that trigger detrusor overactivity. Studies with capsaicin over the past 8 years have demonstrated clinical efficacy with minimal long-term complications. Most of these studies have also shown that the acute pain and irritation associated with capsaicin are a major deterrent to widespread use. Resiniferatoxin (RTX), an ultrapotent analog of capsaicin that appears to have similar efficacy but with much less acute side effects may be more useful. Intravesical instillation of capsaicin or resiniferatoxin is a promising treatment for the overactive bladder.

Pharmacokinetics and effects of intravesical oxybutynin on the paediatric neurogenic bladder

OBJECTIVE

To evaluate the pharmacokinetics of both oxybutynin and its active metabolite, N-desethyl oxybutynin (NDO), when the drug is instilled directly into the bladder in children with myelodysplasia and neurogenic bladder disturbance, in whom it may improve continence and decrease the risk of upper urinary tract deterioration.

PATIENTS AND METHODS

The study comprised 13 children (five girls and eight boys, mean age 9.3 years, range 1-15) with neurogenic bladders who were treated using clean intermittent catheterization and intravesical instillation of a sterile, pharmacy-produced solution of oxybutynin. Steady-state minimum plasma levels of oxybutynin and NDO, together with their effect on urodynamic variables and incontinence, were evaluated. The dose (0.04-0.17 mg/kg, mean 0.1 mg/kg) was instilled twice daily.

RESULTS

The effects of the drug on incontinence and urodynamic variables were pronounced, improving both in most cases. Minimum plasma levels were < 0.3-7.2 ng/mL for oxybutynin and 0.8-14 ng/mL for NDO. The ratio of oxybutynin to NDO was 0.29-0.83 (mean 0.47).

CONCLUSION

There was no clear relationship between minimum plasma levels of the drug or NDO and their clinical effects; however, the combination of oxybutynin and NDO seemed to be more strongly correlated with the clinical effects.

Smooth muscle of the bladder in the normal and the diseased state: pathophysiology, diagnosis and treatment

The smooth muscle of the normal bladder wall must have some specific properties. It must be very compliant and able to reorganise itself during filling and emptying to accommodate the change in volume without generating any intravesical pressure, but whilst maintaining the normal shape of the bladder. It must be capable of synchronous activation to generate intravesical pressure at any length to allow voiding. The cells achieve this through spontaneous electrical activity combined with poor electrical coupling between cells, and a dense excitatory innervation. In the diseased state, alterations of the smooth muscle may lead to failure to store or failure to empty properly. The diseased states discussed are bladder instability and diabetic neuropathy. Bladder instability is characterised urodynamically by uninhibitable rises in pressure during filling, and is seen idiopathically and in association with bladder outflow obstruction and neuropathy. In diabetic neuropathy, many of the smooth muscle changes are a consequence of diuresis, but there is evidence for alterations in the sensory arm of the micturition reflex. In the unstable bladder, additional alterations of the smooth muscle are seen, which are probably caused by the patchy denervation that occurs. The causes of this denervation are not fully established. Nonsurgical treatment of instability is not yet satisfactory; neuromodulation has some promise, but is expensive, and the mechanisms poorly understood. Pharmacological treatment is largely through muscarinic receptor blockade. Drugs to reduce the excitability of the smooth muscle are being sought, since they may represent a better pharmacological option.

Adenoviral-mediated gene transfer to bladder in vivo

This study was designed to examine the potential for gene therapy in bladder in vivo using adenoviral vectors. Gene transfer to rat bladders was accomplished via direct intravesical instillation using a replication-defective adenoviral vector containing a marker gene encoding for Escherichia coli beta-galactosidase (beta-gal). Successful gene transfer was confirmed by analyzing bladder samples for DNA and RNA using polymerase chain reaction (PCR) with primers specific for beta-gal and adeno sequences, detecting beta-gal in full-thickness bladder wall using specific histochemical staining (X-gal) and documenting recombinant protein production. Bladder architecture was preserved, without evidence of distant spread of virus as assessed by PCR. Gene expression was evident for at least 7 days. In summary, bladder cells can be genetically altered using replication-deficient adenoviral vectors via simple intravesical instillation of vector. Introduction of exogenous genetic material is a potentially powerful therapeutic modality for immunomodulation of bladder neoplasms.

Early cystometrograms can predict the response to intravesical instillation of oxybutynin chloride in myelomeningocele patients

Recent reported experiences with intravesical medications in neurogenic bladder patients prompted us to evaluate this form of therapy in 28 myelomeningocele patients who could not tolerate oral anticholinergic agents or did not have adequate control on these agents. A pretreatment cystometrogram was performed followed by intravesical administration of oxybutynin chloride, with a repeat cystometrogram 3 hours later. Patients then began twice daily intravesical oxybutynin for a minimum of 4 months. The mean bladder capacity increased by 41%, the mean intravesical pressure decreased by 47% and compliance improved. Five patients achieved continence and 62% had less wetting while on intravesical therapy. The immediate posttreatment cystometrogram was predictive of the response to intravesical therapy on followup studies. Unfortunately, patient compliance was poor, with only 13 of the 28 patients remaining on therapy for the duration of the study.

Intravesical instillation of terodiline--an in vivo study of drug absorption in rabbit and man

The absorption of intravesically administered terodiline was investigated in 8 healthy volunteers (10(-4)) and in 33 rabbits (10(-4)) M., 4 X 10(-4) M. and 1.6 X 10(-3) M.). In the humans, the amount of drug retained and the serum concentration were registered. In the rabbits, the influence of drug concentration, pH (5 and 9.2) and volume (5 and 20 ml.) were evaluated. Liquid scintigraphy of the bladder wall and of serum and tissue samples from striated muscle, kidney and liver was performed. Further, autoradiography of the bladder wall and calculation of drug retention were done. In the humans, 20 +/- 5% of the administered terodiline dose was retained in the body. Clinically significant serum concentrations were not detected. In the rabbits, 21 +/- 4% of the drug was retained with the pH = 5 terodiline solution as compared with 64 +/- 3% with the pH = 9.2 solution. With increasing terodiline concentrations, drug retention increased, as did the tissue and serum activities. At a given concentration, the total amount of drug retained increased with a larger volume. The drug gradient between the bladder muscle layer and serum was of a magnitude of about 100, independent of the drug concentration within the muscle layer. It is concluded that the pH and concentration of the solution are factors of major importance for the amount of terodiline absorbed from the bladder. Compared with the one obtainable by systemic drug administration, the large gradient between the bladder muscle and the serum is conspicuous, and may be of clinical interest.