Preferred site of blood draw, radial artery. using a 10 or 20cc syringe and a 20g needle. If the radial arteries are shot from repeated sicks or arterial line placements, the dorsal pedal arteries work very well also. Never ever consider the brachial artery, as it is the only source of blood for the hand and can be devistating to thrombus.
To get the stick, I place my left index finger on the pulse feel it for about 10 seconds, visualize thw spot I think the pulse is in remove my finger and insert the needle, bevel up. Works like a charm. Need I mention that I only do this on patients requiring blood gases that do not already have an art. line.
For really edemitis, overly fluid resucitated patients, I like to take a tongue depressor and lay it flat in the ac, then apply pressure to squeeze out the extra fluid. Then, the veins become visible again and will be palpabel when a tourniquet is applied. This is for patients with 3+ edema. It also works well when I go to place a PICC.