Med Nitro glycerine [sub]VS[/sub][b]KA BOOM[/b]

[justwannano]

So whats the difference?
Dad was in intensive care the other day and they had a big bag of liquid nitro hooked up to a iv.
How does that differ from the stuff used to blow stumps?

[dropzone]

Probably concentration. A little of that stuff, injested, goes a long way.

[justwannano]

I was surprised at the size of that nitro bag. It was probably about a quart where as the saline was less than a pint.
That doesn't figure unless you are selling nitro.

[dropzone]

Probably real diluted, but I'm just guessing; marking time until somebody who knows what he/she is talking about shows up.

[Bob Scene]

Intravenous nitroglycerine is supposed to be delivered at a really slow, constant rate, hence the large volume of solution. A day's worth of intravenous nitroglycerine for a 200-lb man might only amount to a quarter-gram of the stuff, if it were given at a constant rate for a whole day. A quarter-gram of most explosives, especially when dissolved in a big volume of water, won't make much of a bang.

[Qadgop the Mercotan]

What Bob Scene said is correct. All the nitro in your biggest local hospital isn't enough to blow off a bottle cap from a beer bottle, and it's diluted further to finely titrate the dose being given. A little goes a long way!

As an aside, I've found IV nitroglycerine very helpful in giving up tobacco. I'd tried all the routine ways; Cold Turkey, gum, patch, and that thing with needles, you know, morphine! And I still couldn't quit. But after they gave me IV nitro for my heart attack, I never touched the stuff again. Try it, all you smokers. Ask your doctor today!

Qadgop, MD

[Billy Rubin]

Medical nitro is a vaso-dilator. It dilates the blood vessels so more blood can flow through. It's purer and more carefully refined than the "boom" kind, but basically the same deal. And it's buffered so it won't blow up easily, but it WILL blow up.

Plastic explosives (in the U.S, I'm not talking about Semtex or any of the exotics) are made of nitro dissolved in otherwise mostly inert substances, but C-3 when warm will "sweat" PURE nitroglycerine, whereas C-4 will not.
Touching a drop of this pure nitro "sweat" will give you a headache (hasving instantly horrendously dilated all the blood vessels in your body at once) the likes of which you'll wish you never had. Hence, the ultra caution with which MD's prescribe medical nitro- your heart may be OK, but your head wishes it were dead.

Still, don't light any matches around the stuff.

b.

[D18]

Maybe this should be in a new thread, but how did nitro come to be used as a medicine? I can't see "this stuff blows up real good, let's see if it has any medicinal use" as being a sound hypothesis for a research program.

Just curious.

[Billy Rubin]

Originally posted by D18
I can't see "this stuff blows up real good, let's see if it has any medicinal use" as being a sound hypothesis for a research program.

Just curious.

Same reasons I note above. The ability of Nitro to dilate the blood vessels was apparent the first time some unfortunate touched the stuff. Let's get in our wayback machine....
(sounds of slamming doors, static, giant switches being thrown, powerful relays kicking in)

"... Doc, I got this headache- It makes me want to die!!!"
Doc, looking at patient's eyes:"Your eyes are more bloodshot than anything I've ever seen- how did this happen?"

Patient:"I'm making some of this new explosive stuff and I accidentally touched some"

Doc: "show me"
doctor goes to lab where nitro is being made, touches some, gets a wailing headache, thinks, "man, this would be good for my patients with angina!"

Any questions?

Whoops, forgot to return to future..

(sounds of slamming doors, static, giant switches being thrown, powerful relays kicking in)


b.

[Chronos]

Um, Billy Rubin, not that I object to wayback machines (far from it!), but could we perhaps close the doors a bit more gently and pad the switches? All this slamming and kicking in the vicinity of so much nitroglycerine is making me a bit nervous...

[Billy Rubin]

All this slamming and kicking in the vicinity of so much nitroglycerine is making me a bit nervous...

Point taken. Consider me chastised. I do not, and have never, done anything which might endanger others intentionally, and I do what I can to avoid accidental endangerment. Leave this kind of things to professionals, and kids, don't try this at home.

b.

(carefully pushing wayback machine back into closet, and silently closing the closet door)

[handy]

I was waiting for that handle, "Billy Rubin" to show up. I thought it would appear eventually.

Found this on the net:
">Do anyone have experince with handling and storage of nitroglycerine
>for medical use?
>
>Nitroglycerine for medical use is dissolved in ethanol, and is
>harmless until spill occur and ethanol evaporates (my idea!). Does
>anybody have any experince, and if so what to do if spill occurs.

If the spill is on a non-porous surface, use a large excess of
sawdust to soak up the liquid and later burn the mixture in
the open in a thin layer and remotely.

If the spill is on a porous surface, repeated treatment with an
18% sodium sulfide (Na2S:9H2O) will destroy the NG."

[handy]

NOTE: I didn't give a URL for that quote cause if I did it would show a page with some nasty formulas on it.

[Billy Rubin]

Hey, it may not be the most original handle but it was the only one handy.

Besides, few outside medicine or chemistry have any idea.

b.

[KarlGauss]

Originally posted by D18
Maybe this should be in a new thread, but how did nitro come to be used as a medicine? I can't see "this stuff blows up real good, let's see if it has any medicinal use" as being a sound hypothesis for a research program.

Just curious.

I was told that, years ago, workers in the Nitro plants would develop angina (chest pain resulting from poor blood flow to the heart itself) on weekends, and the pain would disappear when they returned to work on Monday. Eureka!

[justwannano]

So I'm still wondering why the 2 liter bag. It was decided that his problem wasn't his heart so they didn't even use 1/2 oz of the stuff.

[DVous Means]

Originally posted by KarlGauss

I was told that, years ago, workers in the Nitro plants would develop angina (chest pain resulting from poor blood flow to the heart itself) on weekends, and the pain would disappear when they returned to work on Monday. Eureka! [/B]

Excuse me, but I have to make a comment here.

While nitroglycerin does have a dilatory effect on coronary arteries, the main reason that it relieves pain is because of peripheral venous pooling. As a result, venous return to the right atrium is decreased, cardiac filling is reduced, and distension to the myocardium is less. Consequently, myocardial workload goes down, because less blood needs to be shifted out. The nett effect is that the heart muscle needs less oxygen and nutrient, so the pain eases.

The link between venous return and cardiac output is one of the central principles in IV fluid resuscitation in trauma. IV fluid challenges are also used in non-trauma cases to increase blood pressure.

The basic principle at work is the Frank-Starling mechanism: the more you stretch (distend) cardiac muscle, the harder it will rebound. Hence harder rebound equals greater stroke volume equals greater output.

[Qadgop the Mercotan]

Originally posted by DVous Means
Excuse me, but I have to make a comment here.

While nitroglycerin does have a dilatory effect on coronary arteries, the main reason that it relieves pain is because of peripheral venous pooling. As a result, venous return to the right atrium is decreased, cardiac filling is reduced, and distension to the myocardium is less. Consequently, myocardial workload goes down, because less blood needs to be shifted out. The nett effect is that the heart muscle needs less oxygen and nutrient, so the pain eases.

The link between venous return and cardiac output is one of the central principles in IV fluid resuscitation in trauma. IV fluid challenges are also used in non-trauma cases to increase blood pressure.

The basic principle at work is the Frank-Starling mechanism: the more you stretch (distend) cardiac muscle, the harder it will rebound. Hence harder rebound equals greater stroke volume equals greater output. [/B]

Sorry, Deev, but I think this has been pretty well disproven for the phenomenon of angina. It's certainly applicable for Congestive heart failure, and its associated shortness of breath, but I've seen it in the cath lab: Coronary vasospasm or occlusion with chest pain, add nitro directly into the coronary artery via the catheter, coronary artery dilates, blood flow returns to the myocardium chest pain resolves in seconds. And this was in individuals with normal pump function. Now if the patient is in CHF, and this stressor is causing angina due to a fixed coronary lesion, then the venous dilation does play a role. But that is in the minority of cases (in my, and my cardiac lab's experience).

Qadgop, MD

[honkytonkwillie]

Originally posted by Billy Rubin
Hey, it may not be the most original handle but it was the only one handy.

Besides, few outside medicine or chemistry have any idea.

b.

Few outside of medicine, chemistry or readers of The Straight Dope.

In Cecil's first book, The Straight Dope there was a letter from one of the Teeming Millions asking some variant of "Why is Shit Brown", and he signed his name as Bill E. Rubin or some such.

Cecil made a few wisecracks about first-year medical school students and their lame attempts at humor, IIRC.

[Steve Wright]

Originally posted by honkytonkwillie
Originally posted by Billy Rubin
Hey, it may not be the most original handle but it was the only one handy.

Besides, few outside medicine or chemistry have any idea.

b.

Few outside of medicine, chemistry or readers of The Straight Dope.



Um. Or people who've read (as distinct from seen) The Silence of the Lambs. Lecter gives the name of his red herring as William "Billy" Rubin. The joke is later explained in terms even an ignorant linguistician like me can understand.

[DVous Means]

Originally posted by Qadgop the Mercotan

Sorry, Deev, but I think this has been pretty well disproven for the phenomenon of angina. It's certainly applicable for Congestive heart failure, and its associated shortness of breath, but I've seen it in the cath lab: Coronary vasospasm or occlusion with chest pain, add nitro directly into the coronary artery via the catheter, coronary artery dilates, blood flow returns to the myocardium chest pain resolves in seconds. And this was in individuals with normal pump function. Now if the patient is in CHF, and this stressor is causing angina due to a fixed coronary lesion, then the venous dilation does play a role. But that is in the minority of cases (in my, and my cardiac lab's experience).

Qadgop, MD [/B]


Thanks for that, Qadgop. I can't emulate your cardiac lab experience, so I must accept your input at face value.

However, all the info I have accessed since reading your post place reasonable emphasis on the reduction on left ventricular diastolic pressure (and the consequent reduction in workload), as well as coronary vasodilation, to explain the relief of angina pectoris from glyceryl trinitrate (GTN).

Also, your post refers to direct administration to the site of action via a catheter, so of course an instant coronary effect is achieved. I am more accustomed to the familiar sub-lingual or dermal administration of GTN, where the effect is seen in peripheral vessels upon absorption, prior to moving to the heart via venous return.

Assuming your thoughts reflect the current thinking on this issue, why hasn't the pharmacology information as supplied by drug companies been updated?

[Qadgop the Mercotan]

http://www.aafp.org/afp/20000101/129.html

"The vascular endothelium, once thought to be merely a passive barrier that separates the lumen from the vessel wall, is actively involved in the response to noxious environmental stimuli. These defense mechanisms include release of endothelium-derived relaxing factor (EDRF), which is now known to be nitric oxide.2 Nitric oxide relaxes vascular smooth muscle and also inhibits platelet aggregation and adhesion. The various forms of nitrate therapy provide an exogenous source of nitric oxide.

Nitrates are potent venodilators and, at higher doses, they are also arterial dilators. Nitrate-induced venodilation causes a decrease in venous return to the heart, thereby reducing left ventricular wall stress, which leads to a decrease in myocardial oxygen demand. Dilatation of the stenotic vessel, as well as dilatation of the intracoronary collateral arteries, increases blood flow to ischemic myocardium. Nitrates have also been shown to relieve coronary spasm."

I dunno Deev, I guess a lot of the nitric oxide actions aren't fully understood yet. They did award the Nobel Prize for Medicine to the guy who figured out that Nitric Oxide was involved in this whole process, but there's still a lot of ground to be covered. After all, Viagra was designed as an anti-anginal med, working by futzing with NO2, and look how that actually played out. But examining the above cite tends to support both of our claims, so maybe we should just chalk up the effects to synergy. Two points for both of us!

[KarlGauss]

Qadgop - You beat me to it by fifteen minutes!

From a 1998 review article in the NEJM by Tom Parker (yet another Canadian):


The hemodynamic and antianginal actions of the organic nitrates are mediated through vasodilatation of capacitance veins and conductive arteries. Dilatation of capacitance veins reduces ventricular volume and preload, thus lowering myocardial oxygen requirements and improving subendocardial blood flow. Dilatation of systemic conductive arteries in combination with the reduction of left ventricular volume lowers afterload, another determinant of myocardial oxygen consumption. Nitrates dilate epicardial coronary arteries, including stenotic segments, which can have beneficial effects. (21) Nitrates also dilate collateral vessels, which can improve blood flow to areas of ischemia. (22) <snip> Therefore, the nitrates possess a unique combination of vascular effects that can favorably affect the mismatch between myocardial oxygen supply and demand in patients with coronary artery disease.

[justwannano]

Bill Honkey and Steve


I also like the name but disagree with your statement.

Just ask the thousands of parents who have seen their newborn son/daughter under the billiruben(sp) light.They will never forget.

[Billy Rubin]

nor a med student, for that matter. And now you say it,I DO remember seeing Billy Rubin in Silence, but I didn't intentionally hijack it from there.

And I saw my newborn under a bilirubin light, I'm not sure anyone would look good in that light.

And saying it was "handy" was a bad pun at Handy, who made a comment about the handle, as if to say, "boy, what a totally non-original handle". Took mild offense but since I thought I might be reading it wrong, I just made the comment about it being "handy" rather than being confrontational, as I dislike confrontation, or for that matter, pissing anyone off. And you guys totally lost me with all that medical stuff- whooooooo- I'm glad i'm not a doctor OR play one on TV.

b.