Kit to help you donate blood to yourself

A woman walks into a hospital in critical condition. She has a distended stomach and looks pale. She has just suffered a raptured ectopic pregnancy. And she needs blood. Fast. But she has blood group O negative, a rare type. Soon, the medical attendant rushes over, a gadget in hand, and moments later, has a bag of blood in the other hand, salvaged from the writhing woman. It is transfused back to her. And she is now proclaimed to be in stable condition. Disaster averted. ?

If you have been reading the news lately, you know there is a shortage of blood in the national blood bank. And week in week out, appeals by desperate relatives are made on social media for blood donations to their kin.