Drawing Up Medication: Exploring the Physics

In summary, the process of pulling air into a syringe, inserting a needle into a medication vial, expelling the air, and then drawing up the medication is a way to make it easier to withdraw the liquid medication. This is because it replaces the volume of liquid being withdrawn with air, preventing a vacuum from forming in the vial. This process works by pushing air into the syringe, rather than pulling it in. Even if a vacuum gauge is used, the pressure differential will not exceed 14.7psi (at sea level). However, it can be challenging to get the air molecules to enter the syringe, as they must do so at their own pace. It is like trying to herd cats.
  • #1
Can someone discuss the physics behind pulling air into a syringe, inserting needle into med vial, expelling the air, and finally drawing up medication. This process makes it easier to draw up the liquid med as opposed to simply inserting needing and drawing up med. Thank you.
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  • #2
It provides a volume of air to replace the volume of liquid being withdrawn from the med vial. Without this, the withdrawal of the medical would be producing a partial vacuum in the vial.
  • #3
Air is never pulled into the syringe, only pushed in. Air goes from higher concentration to the void you are creating inside the syringe.

If you put a vacuum gage on the syringe,(no matter how long the syringe was), The pressure differential would never exceed 14.7psi.(Sea Level)
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  • #4
Yes, it is just a bit hard to corral those molecules and drag them in. You just have to let them follow at their own pace. Just like herding cats!

1. What is the purpose of drawing up medication?

The purpose of drawing up medication is to accurately measure and administer a specific dosage of medication to a patient. It ensures that the patient receives the correct amount of medication as prescribed by a healthcare provider.

2. What tools are needed to draw up medication?

The tools needed to draw up medication include a syringe, needle, vial or ampule of medication, and an alcohol swab. It is important to use the correct size syringe and needle for the specific medication and dosage being administered.

3. How do you draw up medication correctly?

To draw up medication correctly, first wash your hands and gather all necessary supplies. Next, remove the needle cap and draw air into the syringe equal to the amount of medication needed. Insert the needle into the vial or ampule and inject the air into the vial. Then, turn the vial upside down and slowly draw the medication into the syringe. Remove any air bubbles and ensure the correct dosage is in the syringe before administering to the patient.

4. What are the potential risks of drawing up medication incorrectly?

The potential risks of drawing up medication incorrectly include giving the patient the wrong dosage, administering air bubbles into the patient's bloodstream, and contaminating the medication with bacteria or other substances. These errors can lead to ineffective treatment or harm the patient's health.

5. Are there any special considerations when drawing up medication for children or elderly patients?

Yes, there are special considerations when drawing up medication for children or elderly patients. Children may require smaller syringes and needles, and it is important to use age-appropriate dosing guidelines. Elderly patients may have difficulty handling small syringes and may need assistance with drawing up medication. Additionally, they may have other health conditions or medications that need to be taken into consideration when determining the correct dosage.

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