The characteristics and management of patients with recurrent blockage of long-term urinary catheters.

Encrustation and the subsequent blockage of indwelling urinary catheters is a common problem affecting up to 50% of long-term catheterized patients. For community patients, the resultant urinary bypassing or painful retention is particularly distressing since professional help is not immediately available. Catheter blockage also places increased demands on nursing time and resources. A prospective longitudinal study of 47 community patients with long-term catheters was conducted. Demographic, dietary and catheter-care data were collected, and biochemical and microbiological urinalysis conducted. Catheters were changed on three occasions, after 6-week intervals, and the extent of encrustation examined. The results indicated that patients can be classified as 'blockers' and 'non-blockers'. 'Blockers' produced two or more blocked catheters and were characterized by high urinary pH and ammonium concentration. 'Blocker status' was also significantly associated with female sex and with poor mobility, but not with fluid intake and urinary output. 'Blockers' were generally managed by 'crisis care' in response to leakage or retention, rather than by planned recatheterizations prior to catheter blockage. Recognition of individual patients as 'blockers' and the establishment of a 'pattern of catheter life' would be useful to planning individualized care.