The development of urologic complications in relationship to bladder pressure in spinal cord injured patients.

The medical records of 88 patients followed through our spinal cord injury clinic were reviewed to determine if elevated intravesical pressures result in more urologic complications than are seen with low pressure bladders. Fifty-two of the patients were noted to have a high bladder pressure (sustained detrusor pressure greater than 40 cm water) on cystogram while 36 had low pressures. All patients had routine urine cultures, urodynamics, ultrasonography, radioisotope renal scans, and excretory urograms. Bladder management was directed at maintaining a low bladder pressure and included one or more of the following: intermittent catheterization, anticholinergics, alpha blockers, transurethral sphincterotomy, or indwelling catheters. Average follow-up was 6 years. Mild degrees of hydronephrosis were noted in seven (14 percent) of the patients with a high pressure bladder and in one (3 percent) with a low pressure bladder. Pyelonephritis was noted in two (4 percent) with high bladder pressure and two (5 percent) with low bladder pressure. Preservation of renal function occurred as the result of patient compliance with bladder management and bladder pressure. Sustained high detrusor pressure, when not corrected, leads to upper tract deterioration which was reversed by aggressive lower tract management.