When fluids are temporarily stopped, the injection cap is placed on the end of the catheter and the needle with plastic cover is placed on the end of the IV administration set to keep the tip of the tubing sterile. Movement of the leg can occlude fluid flow through the catheter. If needed, a splint such as the pictured Mason-meta splint can be used to keep the limb extended to maintain a constant fluid flow rate. The leg and splint can then be bandaged or the splint can be taped to the leg at both ends, leaving the catheter exposed. The use of IV infusion pumps reduces the need to keep the limb extended.
Fluid pumps can often overcome the resistance created by positional changes.
To place a catheter or obtain blood from the lateral saphenous vein, the animal is positioned in lateral recumbancy. The holder is holding off the vein with her right hand. Some dogs have a prominant medial saphenous vein which can be catheterized or sampled. To access the medial saphenous vein, the animal is held in lateral recumbancy but the holder applies pressure on the medial aspect of the leg closest to the table. The technique for placing a catheter in the lateral saphenous vein of the dog is similar to the technique for cephalic placement.