We have been tubing blood in a Pevco Tube system for about 5 years now. We occasionally have a unit get lost in the twilight zone and we usually lose this unit because we can't track it quite fast enough to save it. This is not frequent, and we've never had it happen to an autologous unit. We validated much the same way that John Staley validated. We found that a unit could reside in the tube for about an hour before the temp rose above 10oC. We tube all over the hospital, including two areas that are in different buildings. We tried tubing syringes for neonates, and that usually worked (it worked when we validated), but occasionally the syringes would "explode" in the Ziploc bag. So now we send an aliquot bag and a syringe with filter attached and the nurses draw up the syringe. We have the receiver sign that they have received the blood and tube that receipt back to us. This gives us the official record of who received the tissue, and assures us that the blood has gone to the right place and been noticed within 30 minutes.