Cystometry in children

Feasibility of urodynamic study (combined cystometry and electromyography of the external urethral sphincter) under general anesthesia in children

BACKGROUND

To assess the feasibility of urodynamic study under general anesthesia (GA) we performed electromyography of the external urethral sphincter (EUS-EMG) on 73 children and cystometry (CM) alone on 10 children.

METHODS

Subjects were divided into 3 groups. Those in groups I and II were suspected of having voiding dysfunction with (group I) or without (group II) overt neurospinal defects, while those in group III were thought to be functionally normal. EUS-EMG was performed under light anesthesia following cystourethroscopy to examine structural abnormalities. Atropine sulfate premedication was not used for the anesthetic procedure; muscle relaxants were used only for tracheal intubation.

RESULTS

Voiding was observed in 83% of the patients. Among patients who voided, detrusor-external sphincter dyssynergia (DSD) was noted in 7 (38%) group I patients and 6 (19%) group II patients; in group III, voiding was synergic in all patients. In 10 cases, CM alone was carried out both under anesthesia and in the waking state; anesthesia suppressed detrusor hyperreflexia (DH) in all 9 patients but produced no change in bladder compliance.

CONCLUSIONS

In children with urinary disorders, urodynamic study under GA following cystourethroscopy is a feasible method for assessing EUS function and documenting DSD; DH is not evaluable, however. Stratifying urinary management on the basis of these examinations resulted in satisfactory clinical outcomes.

Natural filling cystometry in infants and children

OBJECTIVE

To evaluate natural filling cystometry in infants and young children.

PATIENTS AND METHODS

The study group comprised 37 infants and young children (mean age, 4.1 years) with various urological conditions. Suprapubic catheters were used in all patients with urethral sensation. Natural filling urodynamic (NFU) studies were performed using an ambulatory recorder and with an observer present throughout. For comparison, 17 of the 37 patients also had slow filling conventional cystometry (CMG).

RESULTS

All NFU studies were successfully completed and the great majority of patients were unaffected by the investigation procedures. In comparison with conventional cystometry there were significant differences. For NFU, there was a lower bladder capacity (means, NFU 122 mL vs CMG 188 mL, P < 0.03); lower pressure rise on filling (means, NFU 5.7 cmH2O vs CMG 16.1 cmH2O, P < 0.001) and higher maximum detrusor pressures during micturition (means, NFU 130 cmH2O vs CMG 78 cmH2O, P < 0.01). Voiding efficiency was also slightly greater with NFU compared with CMG. Detrusor instability was recorded in five patients only during NFU and in two other patients only during CMG.

CONCLUSION

A natural filling cystometry method which incorporates an unobtrusive recording system is likely to be superior to conventional CMG for assessing bladder function in infants and children. This is because (i) bladder function is investigated in near to natural conditions, (ii) the patients are mostly unaffected by the investigation procedures, (iii) there are significant differences between NFU and CMG in the measurements obtained, indicating that CMG may give false indices of bladder function.

Uroflowmetry in neurologically normal children with voiding disorders

A prospective study was undertaken to delineate the role of spontaneous uroflowmetry as screening procedure for functional infravesical obstruction (detrusor/sphincter dyssynergia). More than 70% of thirty-nine children referred for urinary tract infections and/or enuresis in the absence of neurological deficits underwent a complete diagnostic program including intravenous urography, voiding cystography and cystoscopy as well as spontaneous uroflowmetry, cystometry-emg and pressure-flow-emg study. The incidence of dyssynergia was 22%. However, neither the flow curve pattern nor single flow variables were able to identify children with dyssynergia. Consequently uroflowmetry seems inefficient in the screening for dyssynergia in neurological normal children with voiding disorders in the absence of anatomical bladder outlet obstruction.

Urinary flow studies in normal kindergarten--and schoolchildren

The problems in the evaluation of children with suspected infravesical obstruction are shortly reviewed. Based upon literature studies it is concluded, that an isolated urinary flow measurement determining the Qmax is a suitable procedure of screening. Due to different shortcomings of earlier published normal materials, we investigated the spontaneous urination of 205 normal children aged 3 to 13 years in their normal environment. The mictiograph was installed in the toilet of two kindergartens and one school, enabling the children freely to void into the machine upon desire. From the flow curves the following parameters were calculated: Q1 sec, Qmax, Qmax time, and the micturition time, all of them being related to the square root of the voided volume. The data were non-parametrically statistically processed, and the limits of normal values (2 1/2% and 97 1/2% percentiles) are defined for different groups of age and sex. Furthermore, the different flow curve patterns are described, and it is found, that in 90% of the cases they are identical to the adult pattern.

Voiding dysfunction in children

Superficially, the causes of voiding difficulties in children may seem quite simple, but a thorough understanding of the anatomy physiology and neurology of normal and abnormal lower urinary tract function is necessary in uncovering the etiology of often seemingly siple complaints. An ectopic ureter, neurogenic bladder, urinary tract obstruction, or simple urinary tract immaturity, for example, can all cause a child to present with the complaint of "wetting." A familiarity with all the possible causes of voiding dysfunction is required to distinguish significant from insignificant symptoms. While a "wait and see" attitude often results in the spontaneous resolution of a problem such as simple nocturnal enuresis, the misdiagnosis of a severe disorder, such as urinary outflow obstruction, may permit the insidious development of irreversible renal failure. Our purpose in writing this monograph was not to provide a comprehensive guide to the diagnosis of voiding dysfunction in children, but rather to enhance the clinician's appreciation of the complexity of these problems. Our hope is that the perspective that we have provided will obviate the diagnostic and therapeutic exaggeration of insignificant voiding complaints, while assuring that the presence of significant lesions is not overlooked.

Urodynamic studies in anesthetized children

Urodynamic study was done on 31 neurologically normal children with urinary infection and/or severe voiding disturbances. The evaluation was performed with the child under anesthesia because awake testing proved unsatisfactory. Detrusor contraction occurred in 29 children under anesthesia and sufficient data were obtained to identify accurately patterns of dysfunction and to initiate therapy. A method for anesthetic neurourologic study using enflurane is presented, which permits reliable and reproducible urodynamic observations to be made in patients in whom awake investigations are incomplete or unsatisfactory.

Association of urinary tract infection and reflux with uninhibited bladder contractions and voluntary sphincteric obstruction

We studied 53 neurologically normal children with recurrent urinary tract infection who were found to have bladder-sphincter incoordination characterized by voluntary sphincteric constriction during involuntary uninhibited bladder contraction. Increased intravesical pressure was documented during these events and was associated with vesicoureteral reflux in nearly 50 per cent of the children and with abnormalities of the ureteral orifice in 30 per cent of those without reflux. We hypothesize that increased intravesical pressure causes urinary infection in these children and produces a spectrum of intravesical anatomic distortion that predisposes to vesicoureteral reflux. In a prospective uncontrolled study treatment of the uninhibited bladder contractions allowed 58 per cent of the patients to maintain sterile urine without subsequent antimicrobial therapy after cure of the initial infection.