tPA release?

[PharmlyDoc]

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Had an exam this past Friday on hematology. And one of the questions asked (along the lines): When administering tPA to dissolve a fibrin clot, the tPA is released slowly over...
A. several minutes
B. several hours
C. several days.

I don't remember what answer D stated. But in my notes I have written that "tPA released very slowly over several days." Is that wrong? I thought it would be hours, especially in a stroke patient?

 

[PharmlyDoc]

This is what is stated in the notes provided by my professor: "When a clot forms increased amounts of inactive Plasminogen are trapped and require activation by Tissue Plasminogen Activator, (t-PA), which is released very slowly, (over several days!), from the damaged tissue: this delays the onset of clot removal until the necessary repairs have occurred."

 

[joker2400]

Sounds like your notes are referring to endogenous production and the question is asking about pharmacological intervention

 

[NickNaylor]

When administered externally, I would choose the "several minutes" option over the others. I think the usual protocol is a small bolus followed by an infusion over a relatively short amount of time. I'm no neurologist, though.

 

[operaman]

Sounds like your notes are referring to endogenous production and the question is asking about pharmacological intervention

$50 says the prof was actually asking about endogenous production in the test question. People that wrote ambiguous test questions drove me crazy. Don't miss that part of m1/m2 at all!

 

[PharmlyDoc]

So how long does pharmacological intervention take to break up the clot? Here I am, a P1, and I had no idea there was endogenous tPA.

 

[joker2400]

$50 says the prof was actually asking about endogenous production in the test question. People that wrote ambiguous test questions drove me crazy. Don't miss that part of m1/m2 at all!

Wouldn't surprise me at all. Only 3 more months...

 

[Jabbed]

$50 says the prof was actually asking about endogenous production in the test question. People that wrote ambiguous test questions drove me crazy. Don't miss that part of m1/m2 at all!

Unless OP misworded it, 'administering tPA' sounds pretty exogenous.

 

[PharmlyDoc]

I have another question..."stomach acid is the main anatomical immune defense in the GI tract"..."secreting this substance(s) which kills microorganisms:"
a. HCL
B.Pepsin
C HCL and Pepsin
d. non of the above

I put HCL. I know pepsin breaks up proteins in food, but I've never heard of pepsin being used as an antimicrobial. I know some of these questions might seem easy to medical students, but the exams contain 100 questions.

 

[Tipsy McStagger]

I just finished neuro and we administered a fair amount of it. It's weight based dosing, you get a bolus of 10% of the dose over the course of 1 minute, then the rest over the course of 1 hour. Dose doesn't exceed 90mg total. After you mix it, you calculate the dose, calculate the bolus withdraw the excess and trash it, then you just bolus and hang what's left in the vial.

Fun fact: if you mix it and opt not to use it for whatever reason, the company is supposed to buy it back from you.

EDIT: I should mention this is for acute ischemic stroke. I don't know if the guidelines change for MI/PE. I've never seen it used for those.

 

[notbobtrustme]

I have another question..."stomach acid is the main anatomical immune defense in the GI tract"..."secreting this substance(s) which kills microorganisms:"
a. HCL
B.Pepsin
C HCL and Pepsin
d. non of the above

I put HCL. I know pepsin breaks up proteins in food, but I've never heard of pepsin being used as an antimicrobial. I know some of these questions might seem easy to medical students, but the exams contain 100 questions.

It could be both, that's a poor question as well. Pepsin will cleave proteins and this is bad news for microbes.

A better question would have been parietal cells protect the gastrointenstinal tract by secreting what substance?

 

[Jabbed]

I have another question..."stomach acid is the main anatomical immune defense in the GI tract"..."secreting this substance(s) which kills microorganisms:"
a. HCL
B.Pepsin
C HCL and Pepsin
d. non of the above

I put HCL. I know pepsin breaks up proteins in food, but I've never heard of pepsin being used as an antimicrobial. I know some of these questions might seem easy to medical students, but the exams contain 100 questions.

HCl. It's pretty cut and dry once you learn about acid-labile bugs (salmonella, vibrio) vs acid-stable (shigella).

OP be careful with requesting help with test/hw questions on SDN. Mods have made it very clear in the past that this is not the forum for that.

 

[Ismet]

SDN is not for homework/academic help. Please seek help from your professor or institution. Closing thread.