Estimating detrusor pressure at home in pediatric patients with myelomeningocele

Purpose: We evaluated a method of estimating detrusor pressure at home in p atients with myelomeningocele who perform clean intermittent catheterizatio n to empty the bladder. Materials and Methods: Patients with myelomeningocele who perform clean int ermittent catheterization underwent cystometry. At home they determined bla dder pressure before draining a full bladder and after partial draining wit h the bladder almost empty. Home estimate of detrusor pressure was calculat ed using the formula, full bladder pressure - almost empty bladder pressure . Results: A total of 4 boys and 5 girls with a mean age plus or minus standa rd deviation of 9.6 +/- 7.9 years who were enrolled in our study made 16.9 +/- 15.2 home bladder pressure and volume recordings weekly each during a m ean of 5.8 +/- 4.3 months. Mean bladder capacity determined at home was sig nificantly greater than cystometric capacity (354 +/- 185 versus 250 +/- 14 6 ml.). At a mean home and cystometric volume of 190 +/- 110 ml. full bladd er pressure at home was not significantly different from cystometric vesica l pressure (31.0 +/- 8.8 versus 27.5 +/- 7.5 cm. water). At a mean volume o f 23 +/- 15 ml. mean home almost empty bladder pressure was not significant ly different from cystometric abdominal pressure at full and almost empty v olumes (14.1 +/- 5.5 versus 17.0 +/- 7.4 and 15.5 +/- 5.8 cm. water). Mean home estimate of detrusor pressure was not significantly different from cys tometric detrusor pressure (17.0 +/- 6.3 versus 10.2 +/- 9.2 cm. water). Conclusions: Estimation of detrusor pressure at home is reliable and accura te in patients who perform clean intermittent catheterization. These pressu re determinations may be used as a baseline for rapid identification of cha nges in bladder function.