Fluid Flow Patterns Through Drainage Catheters: Clinical Observations in 99 Patients.

ABSTRACT

PURPOSE: To describe patterns of fluid flow through locking pigtail and biliary catheters in patients that underwent biliary and abdominopelvic fluid drainage. METHODS: Contrast movement through catheter sideholes in pigtail and biliary catheters was evaluated retrospectively using sinograms and cholangiograms at 7-10 days post insertion. Dilute contrast injected through the catheter was evaluated by following flow through the catheter shaft and exit from side holes within the body cavity. Exit of contrast through side holes was appreciated and recorded. Included patients underwent biliary and abdominopelvic fluid drainage using 10.2-F catheters. Exclusion criteria included masking of contrast flow through sideholes by catheter angulation, contrast pooling or other imaging artifacts. RESULTS: A total of 99 patients meeting inclusion criteria underwent evaluation of contrast flow through pigtail (n = 81) and biliary (n = 18) catheters. For pigtail and biliary catheters, 91/99 cases (91.9%) showed contrast exiting the catheter from only the sidehole located most proximally to the catheter hub. In 6/99 cases (6.1%) contrast exited no further than the second most proximal sidehole. In 2/99 cases (2.0%) contrast exited no further than the third most proximal sidehole. In no cases was contrast observed exiting from distal sideholes beyond the third most proximal sidehole. CONCLUSION: Retrograde contrast injection through catheters suggests that the majority of the contribution to total output in drainage catheters comes from the most proximal side hole. Contribution of distal side holes to total drainage is negligible or non-existent, therefore the distal segment of the catheter may be considered non-functional.