Behaviour of the Human Bladder during Natural Filling: the Newcastle Experience of Ambulatory Monitoring and Conventional Artificial Filling Cystometry

Abstract

Conventional Artificial Filling Cystometry (CMG) is the Gold Standard investigation of detrusor function although the findings are limited by the constraints of rapid rates of filling with artificial filling media in conditions of restricted mobility and the clinical environment. Recent advances in technology have allowed the use of ambulatory monitoring (AM) of detrusor function during which the bladder fills at natural rates with urine whilst the patient is able to exercise and perform normal daily activities outside the clinical environment. Comparative studies of CMG and AM in the Department of Urology at the Freeman Hospital, Newcastle-upon-Tyne in recent years have shown interesting differences in the results obtained between the techniques. During AM the bladder pressure rise on filling is seen to be lower and associated with a greater incidence of spontaneous phasic detrusor activity than during CMG, whilst detrusor contraction pressures during the voiding phase following natural filling, are generally seen to be higher than during CMG. Several groups of patients, including men with neuropathic bladder disorder, chronic retention of urine and bladder outflow obstruction together with a group of asymptomatic healthy volunteers have been studied and the results presented.

Comparison study of autonomous activity in bladders from normal and paraplegic rats

“…Because of similarities with the phasic non-micturition transients seen in many species including man [Gjone, 1965;Coolsaet et al, 1993;Vaughan and Satchell, 1995;Robertson, 1999], a role in normal bladder ¢lling has been proposed for this ''autonomous bladder activity. '' The exact physiological role for this non-micturition activity remains unclear.…”

Conscious voiding during bladder obstruction in guinea pigs correlates with contractile activity of isolated bladders

“…NVCs during urine storage phase in humans (i.e. DO) are more prevalent in bladder outlet obstruction patients compared with healthy volunteers, and their prevalence rise continuously with increasing grade of obstruction (Robertson, 1999;Nordling, 2002;Oelke et al, 2008). Localized NVCs were also more prevalent and sustained, and have a higher frequency in patients with urinary urgency compared to asymptomatic controls (Drake et al, 2005).…”

“…involuntary detrusor contractions), an inefficient bladder emptying, which leads to increased residual volume, will result in increase in voiding frequency and reduction in voiding volume. It is well established that residual volume is significantly increased in bladder outflow obstruction in human patients and animal models (Rosier et al, 1995;O'Connor et al, 1997;Robertson, 1999;Pandita et al, 2000). The mechanism responsible for increased residual volume and bladder capacity in obstruction is still unclear.…”

“…In addition, no correlation was found between amplitude of involuntary detrusor contractions and subjective report of urgency in patients with OAB symptoms (Romanzi et al, 2001). DO is a common (50-75%) urodynamic occurrence in patients with bladder outflow obstruction due to benign prostatic hyperplasia (Robertson, 1999;Nordling, 2002;Oelke et al, 2008). It is still not completely understood which particular changes in contractile activity of the bladder during urine storage phase could be responsible for OAB symptoms in patients with bladder outflow obstruction.…”

“…However, non-voiding contractions during storage phase have been recorded during ambulatory urodynamics in 38% of healthy volunteers and only few described urgency associated with the detrusor spontaneous activity (Robertson, 1999). In addition, no correlation was found between amplitude of involuntary detrusor contractions and subjective report of urgency in patients with OAB symptoms (Romanzi et al, 2001).…”