Combien de temps peut-on conserver une solution injectable prélevée dans une seringue ?

[dnBQByvHb8Zkawbjpx]

Les faibles doses (<100 mg) sont notoirement difficiles à peser avec précision, à moins d'utiliser des balances de très haute précision. Par exemple, pour préparer la kétamine pour l'IM, il peut être préférable de préparer un lot de cinq injections en dissolvant 500 mg de K dans 5 ml de solution saline, au lieu de peser 100 mg pour une injection (qui pourrait être de 150 mg en raison d'une erreur de balance).

Considérons une solution stérile garantie préparée par cuisson de K dans une solution saline. La solution est ensuite aspirée dans des seringues stériles à l'aide d'aiguilles stériles neuves ou de filtres à seringue de 0,22 um. L'aiguille de chaque seringue est ensuite remplacée par une aiguille neuve. Pendant combien de temps peut-on conserver en toute sécurité une injection ainsi préparée, vraisemblablement dans le réfrigérateur à 4-5 °C ? L'aspect de la stabilité du K ne me préoccupe pas car des études n'ont montré aucune dégradation du K stocké dans des seringues. Je m'inquiète de la sécurité micro-bactérienne des seringues stockées après une semaine ou deux semaines au maximum. Pourraient-elles être utilisées en toute sécurité ?

 

[Paracelsus]

Si la stabilité chimique de la kétamine en solution est bien établie, le principal problème est le risque de contamination bactérienne au fil du temps, en particulier lorsque les seringues préparées sont conservées au réfrigérateur.

Considérations relatives à la stérilité :

1. Préparation stérile : L'utilisation de filtres à seringue de 0,22 µm réduit considérablement le risque de contamination bactérienne, car ils sont conçus pour éliminer la plupart des bactéries. Cependant, certains virus et particules plus petites, y compris les spores, peuvent ne pas être entièrement filtrés, bien que ce risque soit relativement faible.
2. Stockage stérile : Une fois la solution préparée et les seringues remplies, le remplacement de l'aiguille par une nouvelle aiguille stérile permet de maintenir la stérilité. Le fait de s'assurer que les seringues et les aiguilles utilisées sont individuellement stériles et manipulées dans un environnement propre minimise encore les risques.
3. Réfrigération : Le stockage des seringues préparées au réfrigérateur (à 4-5°C) ralentit la croissance bactérienne mais ne l'arrête pas complètement. La réfrigération est efficace pour prolonger la stérilité des solutions injectables pendant une période limitée, car la plupart des bactéries et des champignons se développent plus lentement à des températures plus basses. Cependant, elle n'est pas infaillible contre la contamination, en particulier sur des périodes prolongées.

Sécurité microbienne des vaccins stockés :

1. Première semaine : Si la solution est préparée dans des conditions de stérilité optimales et conservée au réfrigérateur, on considère généralement qu'elle peut être utilisée sans danger pendant une semaine. Cela correspond à la période pendant laquelle le risque de contamination bactérienne reste faible, en supposant qu'il n'y ait pas eu de rupture de stérilité pendant la préparation ou le stockage.
2. Deuxième semaine : La prolongation du stockage jusqu'à deux semaines augmente le risque de contamination bactérienne. Bien que la réfrigération et l'utilisation de matériel stérile atténuent ce risque, certains organismes opportunistes peuvent encore se multiplier lentement dans des conditions réfrigérées. Le risque est plus élevé après la première semaine, et au-delà, la sécurité de la solution devient plus douteuse.

Continuez à utiliser du matériel stérile (seringues, aiguilles, sérum physiologique et filtres) et maintenez des conditions de travail propres pendant la préparation. Étiqueter chaque seringue avec la date de préparation pour garantir une utilisation sûre dans les délais recommandés.

 

[dnBQByvHb8Zkawbjpx]

Merci pour ce commentaire détaillé. J'ai réfléchi dans le même sens : le filtrage n'élimine pas les virus (trop petits), c'est pourquoi j'opte pour la stérilisation par la chaleur à 99 °C comme principale méthode de stérilisation de la solution.

Je prévois de préparer des lots de cinq doses maximum à la fois ; l'une d'entre elles serait consommée immédiatement et jusqu'à quatre seraient stockées. La dernière serait utilisée au début de la deuxième semaine et je suis heureux d'apprendre que mon plan n'est pas outrageusement stupide et/ou dangereux.

Je n'ai pas étiqueté chaque seringue dans mon protocole et je vais certainement le faire, merci de l'avoir signalé.

 

[SoldadoDeDrogas]

I used to do something similar. I would prep a bunch of shots and leave them in a sunglasses case. If you are worried about bacterial growth, perhaps you can just cook it and heat the needle tip right before use?

There was another benefit, I don't know if it applies in EU or where else. In the USA though, if you get caught with a syringe loaded with drugs, they cannot charge you with possession. Some people used to load up all their stuff and carry it around like that.

 

[dnBQByvHb8Zkawbjpx]

We are not on the same page. See this picture how needles are packed. They are individually packed in a sterile pouch, and each needle is under a protective plastic cover so it can't hurt anyone before the actual administration. Unpacked and immediately put on a new syringe I am not concerned about the bacterial safety here. Heating needles would do more harm than good and is absolutely unnecessary.

My only concern is about the drug itself since you never know what hands touched it and how it's contaminated. Syringes, needles, saline, these are all sterile.

 

[SoldadoDeDrogas]

Yes, obviously, my friend. I don't expect you are talking about discount syringes from an open box at the thrift shop. You have to open it and expose it to contamination in order to get the substance into it, though, yes?
Just boil the ketamine solution and load them up. It isn't just the product but the handling and procedure and everything. If a spore syringe can survive, this should have better odds.
The drug itself is probably antiseptic also in high concentration, all the germs would OD

 

[Osmosis Vanderwaal]

99c isn't hot enough to sterilize. It barely sanatizes. Normally one would call that an ultra-pasteurization, thich is the worst place to be because tou've killed any actinomycetes or helpful bacteria that could have protected your whatever, but you didn't get it hot enough to kill thermophiles are endospores. When you don't have labratoy equipment, working between vials with injection ports and syringes is the most sanatar method by about 100 light years. Remember, if you want to keep your vials sanatary, flame is the most effective antiseptic in the world. A split second at 1000 degrees kills basically everything . Flame thos syringe needles before you stick them in the ports
>100mg is a low dose? Half that is more than I take at a time.
You'll be hard pressed to gind a fungal basidiospore or ascospore smaller than 0.22. You won't. They usually start at 20x that size. Bacteria is by and large much bigger even. Viruses, now you ain't going to filter a virus out.
One thing to consider if you are going this route is spring water, ro filtered water, drinking water, they all contain bacteria. Reverse osmosis doesn't remove bacteria. Distilled water is the only way to go. Some bacteria can survive on the trace elements in spring water. One more thing. As a pormer lab tech, the #1 source of contamination is you. Clean out from under your fingernails. Cut them short. Wear gloves. Wear a mask to at least diffuse the bacteria spewing from your mouth. Be aware of your mouth. Keep it closeed, it might as well be a toilet,.

 

[dnBQByvHb8Zkawbjpx]

All used injection material is purchased through pharmacies, packed individually and sterile, relying on reputable brands (BD, Terumo). There is no need to sterilize any such material. Needles are under a plastic cover even after they are removed from their pouch and it would be silly to sterilize them with fire.

I use sterile physiological solution (0.9 % NaCl in H2O, sterile, packed 5 ml per vial) so the only non-sterile substance in the whole process is the drug itself, ketamine in my case. I thought I could bake it to sterilize, then load portions into syringes and refrigerate them until use (no more than 2 weeks). Or I could dissolve K in the solution and boil for a bit to kill any pathogens, then load into syringes. Or I could simply not bother and hope that it has not been contaminated too much and let my immune system handle whatever may get through.

You make good points about protective equipment to limit self-contamination during the process. I will keep those in mind. Coincidentally the original post and the answers are only becoming relevant to me in present time and just in time. Sometimes I like to plan ahead as was the case of this post made 8 months ago.

 

[SoldadoDeDrogas]

When I first started experimenting with syringes it was IM ketamine from liquid vials from the veterinarian. I've shot all types of shit off the street since then, sometimes without much care. It's been about 20 years and the worst thing that has happened was my hand/wrist inflammed badly one time with an infection. I was shooting meth and I was out on the street for about a week.. fun times. That was arguably just my own lack of hygiene or circumstances at the time. Some antibiotics and it went away. I have been pretty careless and reckless towards myself, by my own and definitely by most peoples standards, and am probably more lucky than anything, It all just kinda common sense, you know? That is just to provide an example of what you can get away with, I guess. It is not something to fool around with, but it is not so delicate either. I think you have enough sense.

Anyway, if you do everything proper when prepping them and store them in the fridge like you mention, I would think you would be able to keep them for a while.... months... longer even, without any problem. What about if you added some vinegar or something consumable with antibiotic properties to that end, to keep growth at bay? With all the above prep you mention, with added antibacterial and reheating it before use, I don't see it ever being an issue.

 

[dnBQByvHb8Zkawbjpx]

I am not going to contaminate intramuscular injectables with vinegar or any other home grown bacterial retardant. Working towards the sterility of the shot is much easier for me and does not add any undesired substances.

 

[mycelium]

In prison we used vinegar, stores in a non sterile medicine bottle, to draw vinegar into an old syringe, and squirt into crack, so we could break it down and shoot it.
Just sayin.
I have sharpened a syringe with matchbooks and 2 pennies to remove any burrs.
Little bleach to clean everything before and after...
Good thing I'm not stupid anymore

 

[Osmosis Vanderwaal]

Ketamine hcl melts at a lower temp. rthan even crack, 93c or something, has a ph of about 5.5 in an injectable solution.....I don't think heat sterilization is going to work and the ph isn't enough to hamper bacteria. Most of the time, what happens is, the thing that happens most often, nothing ever happens. If someone asked me and were immunocomprimised or otherwise paranoid, there is at least 1 good solution. 0.022 um syringe filter. About a buck and can be reused and it;ll fix you right up for anything but virus or mycoplasma