A multi-lumen catheter assembly comprises an inner shaft, an outer shaft and one or more features. The inner shaft comprises an inner surface and an outer surface. The inner surface defines a first lumen. The outer shaft is coaxially disposed about the inner shaft and is deformable inwardly toward the outer surface of the inner shaft. The outer shaft comprises an inner surface and an outer surface. The outer shaft is radially space from the inner shaft such that the inner surface of the outer shaft and the outer surface of the inner shaft together define a second lumen. The one or more features are configured to maintain patency through the second lumen as the outer shaft deforms inwardly toward the outer surface of the inner shaft.
