Figure 2.

In vitro experimental design to test locking solution evaporation in catheter segments. (A) Arrows indicate from top-down: Aluminum plug, 7 cm length of catheter, luer stub needle, microcentrifuge tube containing blue glycerol-based dye. (B) Catheters after incubation at room temperature. Catheter on the left was exposed directly to air, whereas catheter on the right was given a white petrolatum-mineral oil coating. Left arrow indicates air gap purposefully placed between locking solution and dye to prevent mixing. Right arrow indicates polyurethane cuff used to mount the catheter within the luer stub. (C) Catheter placed within a constructed humidity chamber. Top arrow, rubber gasket; bottom arrow, polyethylene vent.