Sacral nerve stimulation for urinary dysfunction: the first year of the Scottish national service

Effects of sacral nerve stimulation on postpartum urinary retention-related changes in rat bladder

OBJECTIVE

To examine the effect of sacral nerve stimulation (SNS) on the urodynamic function and molecular structure of bladders in rats following acute urinary retention (AUR) after parturition.

MATERIAL AND METHODS

Thirty primiparous rats were divided into three groups: postpartum, postpartum+AUR, and postpartum+AUR+SNS. AUR was achieved by clamping the distal urethra of a rat for 60 minutes. The postpartum+AUR+SNS group received electrical stimulation 60 minutes daily for 3 days after AUR. In addition to cystometric studies and external urethral sphincter electromyography, the expression of caveolins and nerve growth factor (NGF) and caveolae number in bladder muscle were analyzed.

RESULTS

The postpartum+AUR group has significantly greater residual volume than the postpartum group, but the residual volume decreased significantly after SNS treatment. The postpartum+AUR group had significantly lower peak voiding pressure, a longer bursting period and lower amplitude of electromyograms of external urethral sphincter activity than the postpartum and postpartum+AUR+SNS groups. The postpartum+AUR rats had higher NGF expression, lower caveolin-1 expression, and fewer caveolae in bladder muscle compared with the postpartum rats. Conversely, the caveolin-1 expression and caveolae number increased, and the NGF expression decreased after SNS treatment.

CONCLUSION

Bladder dysfunction after parturition in a rat model caused by AUR may be restored to the non-AUR structural and functional level after SNS treatment.

Electrical stimulation therapy for neurogenic bowel dysfunction after spinal injury

AIM: To assess the efficacy of electrical stimulation therapy in the treatment of neurogenic bowel dysfunction after spinal injury.

METHODS: PubMed, MEDLINE, EMbase, Cochrane Central Register of Controlled Trials (CENTRAL), ISI Web of Knowledge, OVID, CNKI, VIP, and Wanfang Data were searched for clinical studies that evaluated electrical stimulation therapy for neurogenic bowel dysfunction after spinal injury from the date of creation of databases to October 2012. The bibliographies of the retrieved studies were also searched. Researchers read included studies carefully and extracted data strictly.

RESULTS: A total of 11 studies were included. Electrical stimulation therapies mainly included transcutaneous electrical stimulation, transrectal electrostimulation, intravesical electrical stimulation, and sacral nerve modulation. Electrical stimulation could adjust gut innervation, increase the local blood flow of the gastrointestinal tract, promote protein synthesis, and improve bowel control of bowel and symptoms of fecal incontinence or constipation in patients with spinal injury.

CONCLUSION: The current evidence shows that to some extent, electrical stimulation therapy could improve neurogenic bowel dysfunction after spinal injury. However, the number of clinical studies that have been reported on this direction was small, especially the number of randomized controlled trials. In addition, the number of subjects included in the retrieved studies was small, and the intensity, outcomes and follow-up cycles were inconsistent. More large-sample and high-quality clinical studies need to be done to evaluate the efficacy of electrical stimulation therapy in the management of bowel function in patients with spinal injury.