David Hilton Ballard MS, Presenter: Nothing to Disclose

Jeffery Adam Weisman JD, Abstract Co-Author: Nothing to Disclose

Mackenzie A Orchard, Abstract Co-Author: Nothing to Disclose

Jason T Williams MPH, Abstract Co-Author: Nothing to Disclose

Jonathan Steven Alexander PhD, Abstract Co-Author: Nothing to Disclose

Horacio R. D'Agostino MD, Abstract Co-Author: Nothing to Disclose

Currently, there is no evidence suggesting that the number or position of sideholes within drainage catheters has been based on fluid dynamics or clinical principles. The purpose of our study was to investigate the effect of varying catheter sidehole number and position on fluid flow rates in an in vitro model.

Ad hoc customized drainage catheters were constructed with various numbers of sideholes (1 to 6). To optimize flow, each sidehole was created with the same diameter as the lumen of the catheter (15 Fr). Drainage catheters were constructed with sideholes on one side (single-sided model), or pairs of sideholes on opposite sides of the shaft (double-sided model). The drainage reservoir consisted of a cylindrical container filled with water. The cylinder was constructed to maintain a constant pressure independent of catheter fluid evacuation. This constant pressure outflow system was established in the reservoir with a 500 mL pressure head using a fixed fluid inflow with a flow/overflow valve. After the catheters were inserted and the pressure gradient was established, fluid evacuation was evaluated using 10-second intervals by draining the fluid into a collection vessel and recording the volume. A total of 5 trials were performed for each catheter to account for measurement error.

Our data shows that flow rate is maximized at 3 sideholes in the single-sided model catheters. Single-sided model catheters with more than 3 sideholes showed no significant improvement in flow rate. All the double-sided model catheters had significantly better flow rates than their single-sided counterparts. Flow rate was maximal in the double-sided model catheter with 2 holes (one on each side) and there was no significant improvement in the catheters with more bilateral sideholes.

Our results suggest that optimal flow in drainage catheters can be achieved through a design consisting of a single pair of sideholes arranged opposite of each other and inclusion of additional sideholes does not significantly improve flow. These in vitro results illustrate that using fluid dynamics principles to redesign drainage catheters could serve to improve catheter performance.

Clinical observations reveal that drainage catheter distal sideholes are often filled with debris that could be a source of sepsis. Our data suggests catheters with few sideholes achieve optimal flow.

Ballard, D, Weisman, J, Orchard, M, Williams, J, Alexander, J, D'Agostino, H, Drainage Catheter Flow Rate Related to the Number and Location of Sideholes: Does It Matter?.  Radiological Society of North America 2013 Scientific Assembly and Annual Meeting, December 1 - December 6, 2013 ,Chicago IL. http://archive.rsna.org/2013/13015876.html