The spontaneous variation of catheter life in long-stay geriatric inpatients with indwelling catheters.

The spontaneous variation of catheter life, i.e. the time in days between catheter changes, was observed in 20 long-stay geriatric inpatients with initially short catheter lives. The study ran for 6 months. The catheter regimen was standardized throughout the study. The intra-individual and inter-individual catheter lives showed considerable variation. Each patient retained his individual pattern of catheter life. It is concluded that, despite the variation of isolated catheter lives, the median value of repeated observations of catheter life provides a reliable parameter of catheter function.