IV Access Flashcards
If you put something in a blood vessel, it should be called what?
Cannula
What is the size of the ‘over the needle’ cannulas?
10-24G
What is the second type of cannula?
Through the needle
What are ‘through the needle cannulas’ used for?
large, central veins - not commonly used.
In what setting would you more commonly see ‘through the needle’ cannulas used?
ICU settings.
What is the type of cannula where you place a long, flexible IV cannular through the stylet?
Peel away cannula
Are peel away cannulas common?
No, relatively uncommon
When would you use peel-away cannulas?
Into central veins (jugular)
What is a more common cannula that you would place IV into the jugular vein where you pass the wire through the cannula into the vein?
Seldinger/over the wire cannulae
What do you do with a seldinger cannula to open up the vessels and the SC tissues?
Dilate
Once dilated, what do you do?
Place cannula over wire and hold onto wire therefore guid cannula into vein. pull out wire.
When would you use seldinger/ over the wire cannulae?
Long cannula into cranial thorax
Name the 4 steps to the Over the wire cannula placement?
- Insert wire through needle in vein
- remove the needle
- pass the catheter over the wire`
- remove the wire
Name 6 biological properties we want from a cannula?
- Non-irritant - provokes minimal inflamation
- Non-carcingenic
- Non-thrombogenic
- Non-toxic
- Resists microbial adhesion
- Resists biofilm deposition
Name 9 physical properties we want from a cannula?
- high tensile strength
- Resists compression - maintains patent lumen
- optimum flexibility
- low friction coefficient
- dimensional stability
- tolerates physical sterilisation methods e.g. steam, irradiation
- ease of fabrication e.g. heat forming or welding
- non-permeable
- radiopacity - ability to image lost catheter.
Name 8 chemical properties we want from the cannula?
- absence of leachable additives e.g. catalysts and plasticisers
- stable during storage
- stable on chemical sterilisation
- stable on implantation - non-biodegradable
- permits adhesives in fabrication
- accepts surface coatings e.g.hydrogel
- compatibility with chemical compounds and solvents
- MRI compatible
what is the most common material when making cannulas?
Teflon
which material tends to be used for long term?
elastomer silicon
name another materials used to make cannulas?
PVC
Which are the 3 worst materials for creating thrombogenicity?
Polyvinyl chloride
Polyethylene
Polypropylene
Which is the most stiff material?
Teflon
Which is the least stiff material?
Silicone elastomer
Which is the least reactive materials?
Polyether based polyurethane and silicone elastomer
What is the most reactive material?
Polyvinyl chloride
The physical shape of the stylet can reduce what?
endothelial trauma
Which tips are preferable over square cut or bevel ended?
rounded tips.
If the endothelial trauma is reduced, what is less likely to happen?
Thrombosis
Where is the most common cannulation site in small animals and why? What is the problem with this?
Cephalic vein as easiest to restrain.
There is an accessory cephalic vein also in this region.
Where do you start when trying to cannulate a vein?
Always start distally, then more closer in case blow the vein.
Name another common cannulation site in small animals?
Saphenous- medial or lateral
Which saphenous is easier in the cat?
Medial