A simple assessment of the dynamics of xenon-133 diffusion in a plastic catheter

Abstract

The diffusion of xenon-133 into the plastic of injection catheters is well known (Keaney et al. 1971, Peters and Eichling 1972). However, the relative rapidity with which this might occur in some circumstances, and the subsequent loss of xenon to the surroundings, are perhaps not so widely appreciated. These xenon movements are illustrated in the simple experiment described, which attempts to reproduce the conditions in which an injection catheter and xenon-133 might be used. It was found that there was a loss of xenon-133 from the sealed catheter. This loss was abolished by stopping the flow of water in the outer tube. After three hours, most of the remaining xenon-133 was within the plastic of the sealed catheter. Approximately one hour later, some of this xenon had re-entered the lumen of the sealed catheter, shown by the reduction in count rate resulting from a second flushing with isotope-free saline.