Bladder compliance in myelodysplastic children: does antireflux surgery compromise it?

We studied the impact of antireflux surgery on bladder compliance, which was an important clinical parameter in terms of urinary incontinence and upper tract deterioration, in 20 myelodysplastics (group A). For control groups, 31 myelodysplastic children with or without reflux who were conservatively treated (group B) and 19 non-myelodysplastics who were operated on for primary reflux were investigated. The follow-up period averaged 87 months for group A and 86 months for group B. Initial bladder compliance in group A (5.1 +/- 3.7 ml/cm H2O) and group B (5.9 +/- 4.9 ml/cm H2O) was significantly lower than that in nonmyelodysplastics (29.6 +/- 23.1 ml/cm H2O) (p less than 0.01). Antireflux surgery prevented a significant elevation of bladder compliance in group A (6.9 +/- 5.5 ml/cm H2O), while an increase of bladder compliance was significant in group B (10.7 +/- 8.1 ml/cm H2O) (p less than 0.01). In the nonmyelodysplastic group, bladder compliance slightly decreased postoperatively but remained well within the normal range (26.3 +/- 12.0 ml/cm H2O). There was significant correlation between bladder compliance and bladder trabeculation (p less than 0.01), i.e. the higher the bladder compliance, the more normal-appearing the cystogram. We propose a bladder compliance of 10.0 ml/cm H2O as the lower limit of the normal range. Analysis of the present data has led to the hypothesis that any surgical intervention on or around the urinary bladder will result in a low compliance in myelodysplastic patients. We have found, on the other hand, that those who have a normal cystogram, a large bladder capacity, absence of symptomatic urinary infection, and normal renal function before antireflux surgery have a good chance of obtaining the compliant detrusor muscle postoperatively.