Detrusor afterContraction - Is it Pathological

Detrusor afterContraction

Abstract

Background: Aim: Detrusor after-contraction (DAC) is seen in many patients undergoing urodynamic studies. There are no established criteria to define DAC. There is very little data available to suggest whether it is a normal physiological or a pathological finding. The aim of our study was to find the practical significance of DAC. Subjects and Methods: Retrospectively study by collecting data of UDS from period of October 2008 to September 2013. Criteria for DAC were increase of detrusor pressure more than 10 cm H2O after the cessation of urine flow. Results: 540 patients underwent urodynamic study from October 2008 to September 2013. Out of 368 were males and 172 were females. Overall 28 patients of 540 (5.2%) showed DAC during urodynamic assessment. DAC was more frequent in women (16) than men (12). Mean age of women with DAC was 48 7.8 years (Range 17-59 years). Mean age of men with DAC was 5113.3 years (22-71 years). Of the 16 women, 8 had detrusor overactivity, 4 had bladder outlet obstruction (BOO), 2 had detrusor sphincter dyssynergia (DSD) and 2 had other normal bladder parameters. Of the 12 men, 7 had bladder outlet obstruction, 3 had detrusor overactivity and 2 had small capacity and poorly compliant bladder. The pressure amplitude of DAC (pDAC) was significantly higher than pdetQmax: 79.541.1 vs. 31.813.0 cm of H2O (p<0.0002). Voided volume was 280105mL and PVR 196.3mL. Volume at onset of DAC (VODAC) was 20 ml 4.5ml. The ratio of voided volume at the onset of DAC and total voided volume was 0.987 0.37. The flow rate at onset of DAC was 6.9 4.3 ml/sec while Qmax was 18.7 6.8 ml/sec (p=0.0002). Conclusion: There is variability in prevalence of DAC and no association or correlation of DAC with various bladder pathologies with statistical significance. It is not possible to give an explanation to this urodynamic finding. Further prospective studies with adequate sample sizes are needed to give the exact meaning and clinical significance of this urodynamic finding.