Dalteparin - Incorrect route of administration?

Double-Helix, BSN, RN · Mar 10, 2012

See, the problem is that we can't ethically test the information you're looking for. We can't inject Dalteparin ID or IM and record the side effects because this could cause harm to the patient. If a person were to inject this medication incorrectly and have side effects, it likely occurred outside the hospital setting and the exact circumstances of how the medication was given could not be verified. Make sense?

So all we have are assumptions about side effects and absorption rates based on what we know about different routes of administration. Sub cutaneous tissue has very little blood supply, so the rate of absorption is much slower and IM. Muscles are highly vascular, so medication injected into the muscle will be absorbed much faster. In the case of Dalteparin, this would mean the medication may be absorbed too rapidly, leading to increased risk of bleeding. As with heparin, injecting Dalteparin IM could cause bleeding in the muscle, resulting in a hematoma. The patient also won't be getting the lasting effect of the Dalteparin due to the rapid initial absorption into the blood stream.

Conversely, there is even less intradermal blood supply. So a medication injected here will be absorbed very slowly, leading to decreased effectiveness of the medication. Since the maximum amount that should be administer ID is just 10ths of an mL, injecting the entire dose of Dalteparin could cause pain, swelling, redness, and irritation as well as leakage of the fluid from the ID space.

Keep in mind that provided the medication is being injected in the correct location, it's very difficult to give a sub cu medication either ID or IM. The needle is small and short and in many people cannot reach the muscle. Remember that your needles for IM injection are at least one inch long. Your sub cu needle is probably less than half an inch. ID injections have to be done very carefully in certain areas of the body (usually the forearm). Only the bevel of the needle is inserted. So if the medication is injected in the correct area, and the needle enters at the appropriate angle and depth, the chances that the medication will be given ID are very low. But that's why it's important that we teach correct technique before sending someone home on these medications.

Here is a link that could be helpful. Bear in mind that it's not an article or text book link, so it's not appropriate for references for papers. http://en.allexperts.com/q/Pharmacology-3676/2008/9/intramuscular-vs-sub-cutaneous.htm

Aerielle · Mar 11, 2012

Thank you Ashley! :)

Esme12, ASN, BSN, RN · Mar 11, 2012

Nicely done Ashley!