I am the Object of My Pimp's Affection

[andersenpa]

Antithrombin III agonist

 

expand on that- how does it work.

[andersenpa]

AndersEn, do you guys opt for LMWH, or the standard form? Maybe its insurance dependent given the $ difference? It seems that LMWH would be better post-surg though to manage.

 

It depends on what we're using it for.

 

For DVT prophylaxis we use only SCDs, unless they're bedbound >48 hrs, then its UF heparin SQ.

 

We only use LMWH if someone needs coverage and is not yet therapeutic on coumadin, or awaiting a procedure and needs to be off coumadin.

 

Cost is a factor only in that we use UFH over LMWH for DVT ppx.

[andersenpa]

What is a rapid way to determining, from the ABG, what the expected PCO2 should be in a patient with a metabolic acidosis?

[kimq26]

What is a rapid way to determining, from the ABG, what the expected PCO2 should be in a patient with a metabolic acidosis?

 

for every 1meq/L decrease in HCO3- the compensation should be a 1mm Hg decrease in PCO2

 

or

 

PCO2 = (1.5 x [HCO3-] + 8)

[andersenpa]

for every 1meq/L decrease in HCO3- the compensation should be a 1mm Hg decrease in PCO2

 

or

 

PCO2 = (1.5 x [HCO3-] + 8)

 

That's the LONG way....

 

there's an even quicker "Rule Of Thumb".....

[kimq26]

What is a rapid way to determining, from the ABG, what the expected PCO2 should be in a patient with a metabolic acidosis?

 

That's the LONG way....

 

there's an even quicker "Rule Of Thumb".....

 

 

Sorry, had to look back at my notes because we were taught to do everything the loooonnnng way :o

 

So the quick rule o' thumb is:

 

look at the last 2 digits of the pH

e.g. pH = 7.32

HCO3- = 16

pCO2 should be ~32

 

or add 15 to the bicarb

[andersenpa]

Sorry, had to look back at my notes because we were taught to do everything the loooonnnng way :o

 

So the quick rule o' thumb is:

 

look at the last 2 digits of the pH

e.g. pH = 7.32

HCO3- = 16

pCO2 should be ~32

 

or add 15 to the bicarb

 

Correct!

...............................

[kimq26]

Correct!

...............................

 

funny thing is, we had acid-base disorders and ABG's in 3-4 of our classes all taught by different people and a lot of my classmates were totally lost because they all taught different ways of calculating the expected values.

 

My study partner and I compiled the notes into one document and we had the quick way written in on the bottom because it was the best to give a ballpark figure so we knew we were on the right track with the calculations :)

[andersenpa]

funny thing is, we had acid-base disorders and ABG's in 3-4 of our classes all taught by different people and a lot of my classmates were totally lost because they all taught different ways of calculating the expected values.

 

My study partner and I compiled the notes into one document and we had the quick way written in on the bottom because it was the best to give a ballpark figure so we knew we were on the right track with the calculations :)

 

My geek side says it is always best to know and perform those calculations, but the quick & dirty method is good to know as well.

[andersenpa]

What is meant by the term "nonrebreather" in an oxygen mask?

[bradtPA]

What is meant by the term "nonrebreather" in an oxygen mask?

 

The little holes in the face mask are covered with a disc that acts as a valve. It means the discs are left in place to act as a valve, only opening when you expire....

[andersenpa]

The little holes in the face mask are covered with a disc that acts as a valve. It means the discs are left in place to act as a valve, only opening when you expire....

 

When you die? :D

 

j/k

 

You're close. The holes w/ discs are on the side of the mask. They allow expired air to leave the mask, but there is anohter part to dealing with that expired air. Think about the components of a typical NRB mask....

[bradtPA]

The last part you are probably meaning is the reservoir bag. Keep the flow rate at 15L so the bag stays inflated with fresh high concentration O2.

 

Putting them on patients for 20 years prior to PA school had some uses;).

[andersenpa]

The last part you are probably meaning is the reservoir bag. Keep the flow rate at 15L so the bag stays inflated with fresh high concentration O2.

 

Putting them on patients for 20 years prior to PA school had some uses;).

 

So where does the expired CO2 go after it leaves the nose and mouth?

[Prospective PA]

The nonrebreather means that the CO2 upon exhalation is not reinhaled (hence non rebreather) by use of the discs which are one way valves and the reservoir bag has the O2 rich air at 15lpm for inhalation delivering about 90% oxygen...expire??? exhalation/expiration... whatever...LOL

EMT Class has served me well!

Darn Andersen...you responded before I posted!

Edited October 31, 2008 by Prospective PA
Added Darn....

[andersenpa]

The discs allow expired CO2 to leave the mask, but does not influence CO2 entering the reservoir.

 

There is a valve connecting the reservoir bag to the mask. In a regular reservoir mask, CO2 can enter the reservoir, diluting the concentration of O2. In a NRB, the valve allows reservoir O2 to leave the bag but CO2 cannot enter; compared to a partial rebreather which allows CO2 in the bag.

[andersenpa]

How do you define "Negative Predictive Value", and how is it different than Specificity?

 

Remember, no googling!

[meaux]

As to honor your request I have not googled, and in the interim havent seen or read about the answer. I am not opposed to you just telling me. However Ill try an answer it based off some lab medicine lectures we've had. I think the neg. pred. value has something to do with patients who have been correctly diagnosed, but whos lab test are negative. I think this is different from specificity in that even though a test can be sensitive it may not necessarily be specific i.e. D-dimer elevated means there is fibrinogen degradation somewhere, but exactly DVT, PE, s/p MI isnt revelaed from the test solely.

Or it might be different than specificity b/c it is actually the opposite of what should be? This is 1 attempt, please feel free to teach me (anyone) learning is humiliating and fun.

 

meaux

[bradtPA]

As to honor your request I have not googled, and in the interim havent seen or read about the answer. I am not opposed to you just telling me. However Ill try an answer it based off some lab medicine lectures we've had. I think the neg. pred. value has something to do with patients who have been correctly diagnosed, but whos lab test are negative. I think this is different from specificity in that even though a test can be sensitive it may not necessarily be specific i.e. D-dimer elevated means there is fibrinogen degradation somewhere, but exactly DVT, PE, s/p MI isnt revelaed from the test solely.

Or it might be different than specificity b/c it is actually the opposite of what should be? This is 1 attempt, please feel free to teach me (anyone) learning is humiliating and fun.

 

meaux

 

Good job on the neg predictive value. Now think about how to define "specificity" mathematically and you will have the full answer to Andersen's question:).

Edited November 18, 2008 by bradtPA
typo

[SARBU]

Specificity is defined as true negatives / ( true negatives + false positives)

 

In others words it is: those who don't actually have the disease / (those who don't actually have the disease + those who don't have the disease but were tested positive). So if 100 people came into a clinic to be tested for a disease and 70 were tested as true negative, 20 were true positives, 6 were false negative, and 4 were false positives the specificity would be 70/(70+4)

 

I knew that epi would come in handy one day.

[meaux]

That is really confusing, despite its straight forwardness. I am also tired, sick of studying and generally iritable. So really its like any other day thus far in didactic year. Thanks for the lesson though. As for the equation, since 6 were false negatives that means they are positive, right? given the specificity answer 70/(70+4) we know that 6 more actually have the disease. How then does this relate to the literature re: if N=100 and n=70 wht couldnt we just say n=76? I will never be good w/ numbers/stats/ or the like wise. thanks for the help.

 

addendum: I just re-read Brads answers coupled w/ the tight spiral football poster... I get it. I'm still tired, tired of studying and irritable though...:P thanks again

[bradtPA]

That is really confusing, despite its straight forwardness. I am also tired, sick of studying and generally iritable. So really its like any other day thus far in didactic year. Thanks for the lesson though. As for the equation, since 6 were false negatives that means they are positive, right? given the specificity answer 70/(70+4) we know that 6 more actually have the disease. How then does this relate to the literature re: if N=100 and n=70 wht couldnt we just say n=76? I will never be good w/ numbers/stats/ or the like wise. thanks for the help.

 

addendum: I just re-read Brads answers coupled w/ the tight spiral football poster... I get it. I'm still tired, tired of studying and irritable though...:P thanks again

 

I feel the pain, having walked in those didactic shoes. Just think though, its almost Thanskgiving. One more push to finals and you can get X-mas break and a sense of normalcy until the next semester:D.

[meaux]

I feel the pain, having walked in those didactic shoes. Just think though, its almost Thanskgiving. One more push to finals and you can get X-mas break and a sense of normalcy until the next semester:D.

 

 

oh brother, it can not come soon enough. I think for Tgiving break I get to study, b/c we have 3 huge test as a welcome back gift from Tgiving... awesome. ;)

[andersenpa]

You guys have covered it mostly.

 

Specificity- the probability that a person without the disease will have a negative test result.

 

or

 

Sp = TN/TN + FP

 

TN + FP are all the patients who truly don't have the disease

 

NPV- the probability that a person with a negative test result will not have the disease.

 

NPV = TN/TN + FN

 

TN + FN are all the patients with negative test results

[andersenpa]

Why is Hemophilia uncommon in women?