A 52 year old male with a history of hypertension arrives to your ED presenting with similar symptoms as the patient you treated for a PE two days ago. CT scan is “rebooting.” So again, you empirically go for heparin. Soon after, you receive a phone call that CT is up and running and sprint-push your patient to radiology. Then you’re like, uh oh, when you see his aorta is clearly dissecting. In addition to suppressing your panic, what can you do?
[spacer height=”20px”]A few tidbits on Protamine:
[spacer height=”20px”]First, protamine acts impressively quickly to neutralize heparin – within approximately 5 minutes. It does so by forming protamine-heparin complexes.
[spacer height=”20px”]Second, protamine is unique in that its dosing is time dependent. That is, because heparin levels drop rapidly soon after administration, the amount of protamine you will give depends on the time from administration of heparin:
- If given immediately after heparin administration, the dose is 1-1.5mg protamine per 100 units of heparin.
- If given after 30-60min, the dose is 0.5-0.75mg per 100 units.
- If >2 hrs, the dose is 0.25-0.375mg per 100 units.
[spacer height=”20px”]Third, administer protamine by slow IV push, approximately 1ml/minute or 50mg/5min, to reduce the likelihood of hypotension and anaphylaxis.
[spacer height=”20px”]…which leads to the potential dangers of protamine: hypotension and anaphylaxis – in fact, sources recommend having IM epi at the bedside. Delayed bleeds have also been reported, likely from breakdown of the protamine-heparin complexes, the treatment for which is more protamine.
[spacer height=”20px”]Finally and most importantly, protamine was initially derived from fish sperm, but is now made via recombinant biotechnology.
Image taken from:www.flickr.com “party fish”