Thanks for sharing! Is this how you were taught US guided IV cannulation in Iraq?
I'm inexperienced and self-taught, but my technique is somewhat similar to yours. Can someone please critique my method and offer suggestions if they see a big red flag?
1. Typically I map out the vessel and decide the entry point for the skin and vessel and then what direction it will be heading once I'm in the lumen. (The "skin entry" point is just a point in line with the vessel trajectory that will minimise distance travelled and potential collisions with nasties).
2. Line those three points up and penetrate the skin while the US is viewing the vessel where I want to penetrate it (in a transverse plane).
3. Get the tip into the vessel.
4. (Hardest bit for me when I started) slip the cannula over the needle without shredding the vessel wall/bending the cannula.
- I overcome this by doing what DrAmir does above. I.e. once I've visualised the tip in the lumen I advance 1/2mm-1mm and then shift the US probe up, advance and shift, advance and shift. This usually takes about 3-5seconds total and as I get more experienced I'm almost moving both hands simultaneously while keeping the advancing needle tip in view at all times. This way I'm sure I'm in the lumen for a good few mm and the cannula is easily advanced over the needle.
Issues I'm aware of with my approach:
- Apparently, the "proper way" to do these is with an in-plane approach, but I've never tried it before.
- Apparently, the "proper, proper way" to do these is with a complex Pythagorean equation and depth markers displayed on the US screen. You work out your triangle and you know exactly how far you need to advance the needle and to what 3-D point before you hit red gold, which makes sense and is kind of what we do without really thinking about it. However, what I don't understand is how this enables you to get the cannula in easier?
- I KNOW that I map out the vein before I prick and therefore I am comfortabe advancing US probe and needle together without looking ahead once I'm in the lumen, however... when I saw another registrar doing this it made me feel very uneasy about what vessel twist/turn/disaster was 1mm ahead of the probes vision. It making me second guess my approach having watched someone else.
Cheers.