Intravenous (IV) cannulation refers to a procedure in which a cannula enters a vein to allow for venous access. Venous access permits blood sampling, medication administration, chemotherapy, and the administration of fluids, medications, parenteral nutrition, chemotherapy, or other products.
The wall of veins is composed of a three-layered wall. It consists of an inner endothelium that is enclosed by a thin layer of muscle fibers and surrounded by connective tissue. The vein valves promote unidirectional blood flow and prevent blood from pooling in the dependent parts of the extremities. They also hinder the passage of a catheter into a vein.
Where can you insert an IV catheter?
Places for IV insertion:
● Because they don't bend with arm bending, the forearms make a great location for continuous fluids. Not everyone has the best forearm options. In addition, an IV Cannula placed in the forearm vein may not give a great return on blood work. This may be an option, but it should only be considered in an emergency department (ED), where they usually draw blood work during IV cannula insertions.
● Sometimes, the easiest veins for seeing are those in the hand IVs. These veins are often small and can only accommodate 20-22 grams. They can also limit the patient's hand use and may cause injury.
● Large veins are found in the upper arms and hands. Although most facilities prefer to place an IV Cannula in an arm for safety reasons, there are some exceptions. You can access the patient's legs and lower extremities if the patient is very difficult to stick. However, there are high risks of infection.
If the vein is not visible in one extremity, you can look at the external jugular vessels on the patient's side. These veins can often be seen if the patient is positioned with their head slightly down. When the patient performs the Valsalva maneuver (hold your nostrils shut, blow your nose), the external jugular blood vessel expands. An easy, 1 1/4-inch, 20-gauge peripheral IV catheter should suffice. Cannulating the vein is easy with skilled hands, as the diameter and size of the external jugular vein are larger than most arm veins. Before you attempt to insert the intravenous catheter device, attach a 3-cc needle to the hub. Next, apply negative pressure to the catheter. After the catheter is in the external jugular blood vessel, the syringe should be filled with blood. The catheter can then be advanced into the vein.