1
Q
If you put something in a blood vessel, it should be called what?
A
Cannula
2
Q
What is the size of the ‘over the needle’ cannulas?
A
10-24G
3
Q
What is the second type of cannula?
A
Through the needle
4
Q
What are ‘through the needle cannulas’ used for?
A
large, central veins - not commonly used.
5
Q
In what setting would you more commonly see ‘through the needle’ cannulas used?
A
ICU settings.
6
Q
What is the type of cannula where you place a long, flexible IV cannular through the stylet?
A
Peel away cannula
7
Q
Are peel away cannulas common?
A
No, relatively uncommon
8
Q
When would you use peel-away cannulas?
A
Into central veins (jugular)
9
Q
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?
A
Seldinger/over the wire cannulae
10
Q
What do you do with a seldinger cannula to open up the vessels and the SC tissues?
A
Dilate
11
Q
Once dilated, what do you do?
A
Place cannula over wire and hold onto wire therefore guid cannula into vein. pull out wire.
12
Q
When would you use seldinger/ over the wire cannulae?
A
Long cannula into cranial thorax
13
Q
Name the 4 steps to the Over the wire cannula placement?
A
- Insert wire through needle in vein
- remove the needle
- pass the catheter over the wire`
- remove the wire
14
Q
Name 6 biological properties we want from a cannula?
A
- Non-irritant - provokes minimal inflamation
- Non-carcingenic
- Non-thrombogenic
- Non-toxic
- Resists microbial adhesion
- Resists biofilm deposition
15
Q
Name 9 physical properties we want from a cannula?
A
- 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.
16
Q
Name 8 chemical properties we want from the cannula?
A
- 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
17
Q
what is the most common material when making cannulas?
A
Teflon
18
Q
which material tends to be used for long term?
A
elastomer silicon
19
Q
name another materials used to make cannulas?
A
PVC
20
Q
Which are the 3 worst materials for creating thrombogenicity?
A
Polyvinyl chloride
Polyethylene
Polypropylene
21
Q
Which is the most stiff material?
A
Teflon
22
Q
Which is the least stiff material?
A
Silicone elastomer
23
Q
Which is the least reactive materials?
A
Polyether based polyurethane and silicone elastomer
24
Q
What is the most reactive material?
A
Polyvinyl chloride
25
The physical shape of the stylet can reduce what?
endothelial trauma
26
Which tips are preferable over square cut or bevel ended?
rounded tips.
27
If the endothelial trauma is reduced, what is less likely to happen?
Thrombosis
28
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.
29
Where do you start when trying to cannulate a vein?
Always start distally, then more closer in case blow the vein.
30
Name another common cannulation site in small animals?
Saphenous- medial or lateral
31
Which saphenous is easier in the cat?
Medial
32
How does the dog have to be restrained for saphenous cannulation?
Laterally
33
What is common with saphenous veins and why?
Swelling, because so superficial
34
Which vein access is useful for long-term therapy and regular sampling?
Jugular
35
What is the advantage of multi-lumen cannuli?
Do not have to mix what we are administering to the animal with our blood samples
36
Which vein do you use with animals and what have you got to be careful with?
Lateral auricular vein
CARE because the auricular artery is in the centre of the ear
37
Which other species can you use the lateral auricular vein?
Breeds with long ears e.g. bassetts, and sheep (maybe even horses)
38
What can help reduce discomfort when cannulating?
EMLA cream
39
What does EMLA contain?
Lidocaine and pralicaine - leave for 20 mins
40
What size cannula for very small patients?
22G (blue)
41
What size for most patients including cats?
20G (pink)
42
>20kg dogs?
18G
43
Very large dogs?
14-16G
44
What is the relationship between flow through the catheter and length of the catheter?
They are inversely proportional
45
What else is flow inversely proportional to?
The viscosity of the fluids
46
Why do we need to try and place the largest cannula possible?
Because if we half the radius, the flow decreases x16
47
Name 5 stages of preparing the site for cannulation?
1. clip, part, scissor the hair
2. surgical scrub
3. alcohol
4. contact time
5. dry hair before cannulaiton
48
What can be an advantagous communication method when securing the cannula?
Colour coding of bandages.
49
What colour would an IV cannula be wrapped with?
Red vet wrap
50
What colour would an arterial line be wrapped with?
Green or white - know it is not normal IV cannula
51
Name 4 precautions that should be taken to maximise the IV cannula efficiency?
1. check cannula regularly and flush with 1IU/ml heparinised saline every 6 hours.
2. Normal cannulae can be maintained for up to 3 days after which they should be replaced
3. Swab ports prior to injections
4. Replace giving sets, bungs and T ports after 3 days.
52
Name 7 complications associated with cannulae?
1. Extravasation
2. Thrombosis (where do the thrombi occur)
3. Thrombophlebitis (inflammation of the vein)
4. Infection
5. Emboli (air, catheter)
6. Exsanguination
7. Haematoma/ abscess following IV infusion
53
How can you identify thrombophlebitis?
Swelling of neck and jaw
54
Name 5 treatments for thrombophelbitis?
1. Antibiotics (B/S, culture)
2. Raise head
3. Anti-inflammatories (systemic and topical)
4. heparin
5. Vasodilators
55
How to avoid thrombophlebitis?
Take care with sterility and carefully check cannula and swabbing prior to injection.
56
What type of cannula is useful for sampling?
Butterfly.
57
What is the issue with butterfly cannulas and why?
They are difficult to secure without damaging the vessel because the cannulas are metal.
58
What can butterfly cannulas be used for in small animals?
Drain haemothorax and pyothorax in small animals.
59
Why would you chose to use butterfly catheters?
They are very stable.
60
What are vascular access ports?
They are placed over the top of the vein and are good for giving repeat doses of fluids to cats with renal failure or chemotherapy drugs.
61
What is an intraosseous catheter?
A 16-20G bone marrow needle
62
What is the G for needle used in neonates and birds?
18-25G
63
What is the main intraosseous needle?
Cook intraosseous needle.
64
Name 2 scenarios where you would use the intraosseous catheter?
1. patients with inaccessible peripheral veins
2. those in circulatory collapse needing fluids, blood products, or drugs - quick access to bone marrow sinusoids and medullary venous channels.
65
What does Intraosseous access allow?
Rapid delivery of fluids (up to 11ml/min) to neonates, small animals and birds.
66
name 4 commonly used sites for intraosseous catheters?
1. intertrochanteric fossa of femur
2. tibial tuberosity
3. greater trochanter of femur
4. wing of ileum
67
Where is the most common interosseous site in small animals?
Intertrochanteric fossa of the femur
68
Name one more type of cannula which can also be implanted under the skin?
Subcutaneous cannula - not used very much anymore.
69
What is an ambulatory infusion?
An animal is freely moving around with no tether e.g. larger animals that can be fitter with jackets to carry infusion pumps.
70
What is biocompatibility?
Good toleration of impants by animal tissues after implantation
71
Catheter/ cannula?
Flexible tube inserted into body cavities or organs for mendical or experimental procedures.
72
Dehiscence?
Bursting open or splitting along natural or sutured lines.
73
Friction coefficient?
Surface friction influences how easily a catheter can be inserted into a blood vessel
74
Haematogenous spread?
Spread of microbial infection through the blood stream
75
Thrombogenic?
Property of causing or promoting blood clotting.
76
Septum?
The thick polymer diaphragm allowing sealing a vascular access
77
Vascular access port?
An implantable chamber for intermittent access of catheters by puncture via a self-sealing septum with a special (Huber) needle.
78
Venepuncture?
Insertion of hypodermic needle through skin into vein to withdraw blood samples or administer compounnds.
CPS
flashcards
Decks in class (21)
# Cards
-
Introduction to CPS6
-
Introduction to Anaesthesia50
-
Premedication127
-
Induction of anaesthesia177
-
Maintenance94
-
IV Access78
-
Breathing systems101
-
Support and Monitoring the Anaesthetised Patient99
-
CPR - Cardiopulmonary Resuscitation and Recover Guidelines106
-
Recovery from anaesthesia66
-
Analgesia 195
-
Analgesia 256
-
Principles of Radiography69
-
Principles of radiological interpretation60
-
The Consultation5
-
Routine Fertility Visit41
-
Soft Tissue Surgery90
-
Surgery, preparation, protocols and good theatre practice112
-
Surgical materials60
-
Sampling Techniques105
-
Cytological examination58
