Thursday, July 4, 2019

EPISODE 03 - INTERNSHIP DIARIES (Let me gain access into your veins)

(Lesson 1.2)

Inserting an IV line or an Intravenous line is a very much of an expected skill from a Medical professional. Although often performed by Nurses, the skill can come handy at any time because in a case of a hard insertion the nurse or the ancillary staff may refer the patient to you to perform.

Before inserting an IV line you need to know what is an IV Cannula or an IV Catheter.

A cannula or a catheter is a small tube made out of medical grade materials that would allow a medical professional introduce or extract a substrate to or from the body. In a case of an INTRA-VENOUS cannula the access is taken in to the VEINS.

Usually an IV cannula can be used to introduce IV fluids, IV medications as well as sometimes to draw blood(often at the insertion moment).

1. The catheter itself is composed of (a) a tip for insertion into the vein, (b) wings for manual handling and securing the catheter with adhesives, (c) a valve to allow injection of drugs with a syringe also called a LUER lock-valve, (d) an end which allows connection to an intravenous infusion line, and capping in between uses.
2. The needle (partially retracted) which serves only as a guidewire for inserting the cannula.
3. The protection cap which is removed before use.

(By courtesy of Wikipedia ( retrieved 7/5/2019)

These cannulas come in different shapes and sizes, and the sizes are measured in BIRMINGHAM GAUGE SYSTEM often abbreviated as G. In this system the lower number is having a higher diameter and a higher number is having a lower diameter of the catheter tube. (This is different from French Gauge System where it is opposite from this numbering system and is often used in NGT tube sizes)

So, an 18G IV cannula is larger than a 20G IV cannula.

The recognizing of these cannulas are done by the colour of its Luer lock-valve or the tip of the needle in some varieties.

The colours are pretty constant throughout the world but sometimes it differs. So always refer to your senior before checking out a cannula for the first time or better yet, READ WELL of its packaging.

(Note that in some countries 26G could be of Purple colour)
- Table by courtesy of Wikipedia (Retrieved 7/5/2019) -

Check for your needed equipment and material.
  • Alcohol or Hand Sanitizer/Soap and water
  • An alcohol wipe. - To sanitize the skin
  • A tourniquet. - To block the venous flow and engorge the vein as well as fix it.
  • An IV cannula - As mentioned above.
  • A suitable plaster or a Tegaderm® - To fixate the IV cannula/catheter on to the skin
  • A syringe with normal saline - To flush the Catheter
  • A clinical waste bin with a sharp disposal section - To dispose the waste including the needle.


  1. Identify a visible and/or tangible vein. Try to feel it. A rule of thumb is, the better you feel the vein the more successful your insertion will be.
  2. Once you identify the vein, apply the tourniquet and recheck on the vein if its engorged and tangible.
  3. Apply alcohol on your hands and clean it. Wear your gloves properly as explained before; in case you were already wearing gloves, check if you can request for a change of your gloves. Touching a patient without gloves is discouraged.
  4. Clean the patient's skin with Alcohol wipe, a cotton ball soaked in Isopropyl Alcohol 70% or Ethyl Alcohol 70% is alright.
  5. Before inserting the catheter and check if the catheter tip is clear without any manufacturer's defects such as a defect end. Check the needle for its bevel up. 
  6. Stretch the skin distally, and look for your insertion point. If your vein-in-concern is not much engorged you can try slightly tap on it.
  7. Tell your patient to expect a sharp pinch on their point of insertion.
  8. Insert your needle beveled up, usually around 30-45 degrees to the skin and advance your needle to see if there is a flashback of blood at the hub of the syringe.
  9. If you see the flashback, then advance the whole needle about 2-3mm and then retrieve the needle slowly and check if a streak of blood is following the returning needle. If it does...Congratulations! IF NOT, try withdrawing the needle a bit and change the position until you see the flashback.
  10. If you cannot do it while the needle is inside, then retrieve the whole catheter and re insert at a different point of a different vein.
  11. If you still cannot, then ask for help from a senior.
  12. In the fortunate incident of you are already inside the vein, remove the tourniquet and while removing the needle, give pressure to the top of the cannula tip already inside the body so the blood will not reek out making your field a mess!
  13. Insert your prepared flush into the catheter and try to inject. If it proceeds with no resistance, then you are good to go!
  14. Get your Primed IV line or HEPLOCK (which is used to administer IV medications in a later  time via the catheter and it will stop the blood from reeking out) or close the end with the white cap of the needle(Often used with those catheter types with Luer lock-valve where a heplock is not needed)
  15. Take your previously prepared Plasters or already opened Tegaderm® and secure the IV catheter on to the skin. There are several methods of securing the IV catheter on to skin using plasters. We will discuss 
  16. Dispose your needle to the sharps disposal.
  17. Clean and wash your hands.

Congratulations, you are done with your IV catheter/cannula insertion.


You look at the face of the patient after finishing your work, and you are proud that you got access in one hit and did not spill the blood.

"Thank you doctor!" Your patient thanks you.

"You are welcome!" You smile and leave the patient with your tray.


Thanks guys for the support! Thanks for the messages you have been sending to my Whatsapp requesting for more articles. We will try to provide more topics soon. 

With love,



  1. Thank you😊😊😊

  2. Love this site! Makes everything easy 😎.

    1. Thanks alot! We at Medicowesome want to give our awesomites their best shot at everything! :)

  3. Is there any specific way we have to clean the site with alcohol?


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