screen-shot-2016-11-18-at-10-11-01

This is another fabulous study and thanks to the Wessex guys for this AGAIN! Click their image to see the full post.

WHY IS THIS RELEVENT?
IJV cannulation is the commonest point of IV access used in most ICU’s. We all get so used to the traditional short axis ‘circle’ view of the vein, but there are other ways to visualise the it that could be safer.

I am trying to encourage more and more of our trainees to scan the vein from the long-axis angle. This study looks at a happy half-way view; the oblique.

Aside from the fact you can see the needle in full length in LAX, it can also get you out of trouble when a wire just won’t seem to feed, yet you are in the vein. It also permits easier peripheral access under ultrasound if you are well practised in the technique. My philosophy is – why look at a snapshot of an object, when you can see the whole thing. Maximise to optimise!

So…does the use of an oblique compared to short- and long-axis approach increase success rate and decrease complications?

DIFFERENT VIEWS – have a go!

This is brilliant, as we don’t often think of different ways to scan the good old IJV…and some views may indeed be safer than others??

Short-axis (SAX)
Probe placed transversely over neck
Needle introduced in a plane perpendicular to long-axis of transducer

See SAX sweep here
Long-axis (LAX)
Probe place longitudinally over neck
Needle introduced underneath footprint of probe following its long axis

See long-axis access here
Oblique-axis (OAX)
SAX first obtained
Probe rotated to a position midway between SAX and LAX view
Needle introduced underneath footprint of probe aiming from lateral to medial

WHAT WERE THEY LOOKING FOR?

  • Primary outcome:
    • First needle pass cannulation rate (needle pass was considered as any forward movement of needle without any backward movement, irrespective of skin puncture)
  • Secondary outcome:
    • Number of needle passes until successful cannulation
  • Cannulation time measured in seconds
  • Incidence of mechanical complications
    • including arterial puncture, posterior wall puncture, pneumothorax and haemothorax
  • Incidence of catheter-related bloodstream infection

The Bottom Line Crew state…
This study confirms the view that ultrasound-guided IJV cannulation is quicker and technically less demanding in SAX compared to LAX but is associated with greater risk of complication. OAX is a relatively less well-known approach which has the potential to combine the advantages of SAX and LAX but requires further evaluation and training.

See our IJV cannulation video link here