Brief Answer:
not dangerous.

Detailed Answer:
One in 6 people who smoke marijuana have significant lung irritation effects from it. They would notice it. If they don't notice wheeze, difficulty breathing, shortness of breath limiting activity, then they don't have enough to be a surgical risk.
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A few more points. What percentage of people who get breast implant surgery smoke marijuana? Personally I do not know any who do not. In this context, do not expect the surgeon nor anaesthesiologist to be surprised, critical, stop the surgery, etc. They might want a chest x ray if they haven't already. If you smoke cigarettes, they should have done the chest x ray.

There can be withdrawal symptoms that are generally minor from stopping. These usually occur within 3 days of stopping and if they aren't there by then, they are not going to happen/won't be much. If someone is going to be in the hospital a day, one is going to potentially have some withdrawal if one didn't stop right up to the surgery.

For these reasons it is recommended to tell the doctor all your medical information including use of illegal drugs.

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Brief Answer:
oh, that's different.

Detailed Answer:
No, it stays in the body for about 5 days. It is quite dangerous and has considerable withdrawal that is quite unpleasant but not actually dangerous. Use of methamphetamine will affect wound healing by hurting circulation and should not be used. It should really be avoided until the area is fully healed (months).
This should be told to the surgeon and the anaesthesiologist. The medicines used during surgery INTERACT A LOT with methamphetamine and might even interact a bit with the withdrawal from methamphetamine. This might cause the surgery to be postponed and if the surgeon and anaesthesiologist decide that, they have good reasons and likely horror stories of when they did NOT postpone.
This is potentially serious and you are putting your life and health in NEEDLESS jeopardy by not telling the doctors about it. BUT, worst case, you've got to get off of it and the surgery is held off for maybe 2 months (pessimistic worst case).

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Brief Answer:
several points.

Detailed Answer:
complications and a worse life yes, die I think is overstating things.
complications:
feeling awful from withdrawal; you know the likelihood of this better than I do. If you never have a significant down, good. If you lie around until the next hit if you go without methamphetamine for a day (and this is very common) then this will happen a bit worse after surgery and will be a complications. Not a fatal one.

Being addicted. If you have to use 1-2 days after surgery it will affect circulation and healing and that can cause serious complications on how well the implant heals/looks/etc. Should avoid ANY use for months after and should get advice on this from the surgeon.

Being thin. Lowers resistance and lowers healing and makes the contour of the implant not as natural. Technically can be fatal BUT requires some other bad thing to also happen for this to be an issue. If the surgery goes normally, this isn't a risk of fatality but is still a risk to how good things turn out.

There are many, many other risks of methamphetamine use, but they are mostly from INTRAVENOUS use, which has a whole lot of complications.

Methamphetamine is going to be detectable. If it wasn't screened for already, it is unlikely that it will be screened for on the way into surgery. Never-the-less, it is better to tell the surgeons and anaesthesiologist about all drugs and medicines one is on prior to the surgery.

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Brief Answer:
perfect height and weight

Detailed Answer:
not really on the methamphetamine. The detection is under 1/1000 of the peak amount. It is very very sensitive. On the other hand it doesn't get stuck away in fat at all the way marijuana does. So, the length of time it is detectable doesn't change, doesn't go up or down, isn't fixable. IT IS DISGUISABLE, but don't. Decongestants show up on screens as amphetamine. It sounds like it is over 3 days between last use and the time they will screen (if they do) it is possible it is below detection by 3 days and very likely by 5 days. It is guaranteed to show up on a screen if you do more methamphetamine or if you do something that looks like it (decongestant).
On the other hand, having the urine SLIGHTLY diluted by keeping reasonably hydrated (1 to 2 liters of fluid a day DEFINITELY NOT FIVE LITERS WHICH CAN CAUSE WORSE COMPLICATIONS THAN METHAMPHETAMINE). I've literally seen more complications from water than meth but meth is very rare in my location.

Also, on the withdrawal, you know when this occurs after the last use. In general, if it hasn't occurred by 2 days after last use, it isn't going to happen. So, if no further use, this seems very unlikely to be a complication.

For the sake of completely answering question.
http://www.nhlbi.nih.gov/health/educational/lose_wt/BMI/bmi-m.htm
is a weight calculator. None of them give more than a crude guideline AND
at 23 BMI, don't lose any weight, but you are in a perfectly fine weight range.

I must mention, cigarettes are really also very bad in this context. There is more lung effects from cigarettes than methamphetamine, there is some wound healing and circulation effects (less than meth). BUT the effects on body contour, appearance, aging, etc are really quite bad from cigarettes. I frequently see women with implants where the skin has shrunk around the implant from cigarettes use, and things get droopy. ew. So, maintain weight, stop the drugs, but also stop the cigarettes if that is applicable.

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Brief Answer:
Those are good

Detailed Answer:
first, the overall risk is tiny.
these are guidelines to have the best outcome, including long term appearance. possible.
regular diet not starving is best.
long term quitting cigarettes is associated with repair of some damage...about a total of a quarter cup of lung increase in 2 years as posed to non smokers who lose that much lung in the same amount of time or smokers who lose double or those with cold who lose 4 times as much lung as a non smoker

BUT this is over years not for surgery

INCENTIVE SPIROMETRY will help in weeks to build up lungs

BUT unless you have very bad lung disease you won't notice any effect from it.

stopping stuff that is bad is the best. and easiest health change
others like water and exercise can be overdone

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