If they have pitting edema everywhere and you can ' t see or feel anything , push the skin down in spots where you think there might be a vein and if you push the edema away , you can visualize the vein better in that spot and find options no one else knew existed . Also , people emphasize feeling over being able to see the veins and I agree that the ones you can feel are probably better quality HOWEVER , on people who just have terrible veins , sometimes you can ' t feel anything and I ' ve gotten some impossible sticks going for the shadow of what I think might be a vein and what makes sense anatomically with a 22 g or 24 g probably wouldn ' t work with anything bigger . My hospital doesn ' t train nurses to use ultrasound so we ' ve just developed xray vision . I ' ve found vein finders to be a complete waste of time .