What is dead space in relation to IV therapy?

Answer 1

It's the volume of the tubing between your syringe and the patient. Suppose your patient has an IV line and you are injecting 0.5 cc into a port. Let's say the tubing from the port to the patient's vein is a foot long. That 0.5 cc is such a small volume that it won't make it into patient. It will just sit inside the tubing.

In order to get it into the patient's vein, you will need to chase it with a saline flush or something. The basic idea is that whenever you are injecting something into an IV (either by hand or using a pump), you need to chase it with a volume greater than the dead space. Otherwise, your drug is going to sit inside the tubing instead of going into the patient.

Answer 2

Hi. Here is a PDF file : http://www.cja-jca.org/cgi/reprint/42/7/658.pdf#search=%22dead%20space%20iv%22

The idea is that water or saline is the first fluid to be delivered in an IV. If it was pain medication then the patient would not get relief until the medication reached the IV site.