00:01
Hello.
00:02
Let's take a look at bleeding disorders but this is from a functional point of view.
00:05
Think about that for a second as you move forward with our differentials.
00:09
But functional, you don't necessarily have to have a decrease in platelet count, do you?
Functional, I want you think of the normal process of hemostasis that we've discussed.
00:23
When there's endothelial injury, you had expression of von Willebrand factor which is then bound to glycoprotein Ib.
00:32
If there's is a deficiency of glycoprotein Ib,
hereditary deficiency, this is then referred to as being Bernard-Soulier Syndrome
in which we can expect there to be lack of adhesion and there's an increase in bleeding time.
00:48
That's what your focus is going to be on when dealing with Bernard-Soulier.
00:53
What if the other glycoprotein, it was called IIb/IIIa, and it was responsible for what step?
Aggregation.
01:03
So here also you would find an increase in bleeding time,
but the biggest difference between the two, would be the step in adhesion,
would be a lose in Bernard-Soulier.
01:13
The step in aggregation, would be lose in Glanzmann's Thrombasthenia.
01:18
Aspirin we talked about where you inhibit thromboxane therefore you don't have aggregation,
its a functional issue but it is an acquired type, isn't it?
Not hereditary.
01:31
Other NSAIDs of course, would be reversible including let's say ibuprofen.
01:36
Other issues in terms of drugs, remember the word or letters GREL,
and whenever you found the letters GREL in a drugs such as Clopidogrel, or Prasugrel, or Ticagrelor
then that was an issue or it was a target of your P2Y12 receptor antagonism for ADP
in which you are unable to then express glycoprotein IIb/IIIa.
02:05
So here, you prevent the step of aggregation on purpose.
02:10
Or Abciximab, that we talked about, it's going to particularly target glycoprotein IIb/IIIa,
and once again you will prevent platelet aggregation.
02:20
In other words, you are purposely creating function abnormalities with these drugs, aren't you?
Because you're trying to treat a patient who has platelet thrombi.