1. What is a good anatomical reference point for checking CVC depth on chest X-ray?
The carina is readily identifiable on the chest x-ray. This and its correlation with the midpoint of the superior vena cava (SVC) makes it an ideal landmark. The carina is about 6 cm long so provided the CVC tip is within 3 cm of the carina it probably lies safely in the SVC.
2. Which is the correct formula for estimating the distance in centimetres from the right subclavian vein to the junction of the superior vena cava and right atrium?
3. Of the following complications of a sub-clavian central line insertion, which is more common on left side?
4. When inserting a CVC into the right internal jugular vein of a 150 cm tall woman, which of the following skin-to-tip depths is most likely to correctly place the tip?
Check the Peres equations (page 9 of the written guide).
In the case of a right internal jugular vein insertion, the equation is (height in cm / 10) - 1.
5. Which of the following should not be attempted via a peripherally inserted central catheter (PICC) in the basilic vein?
CVP measurement via a PICC line is prone to error.
6. What is the most effective way of preventing an accidental air embolus during and internal jugular vein CVC insertion?
It is all about keeping the pressure gradients in favour of fluid coming out of the needle / CVC. Mainly a concern in the non-intubated patient.
7. When selecting the most appropriate CVC insertion site, of the following investigations, which is the least important?
Core temperature, platelet count and renal function can all affect haemostasis, which is a key factor in deciding the safest insertion site. As an aside, a low platelet count is more important than deranged clotting studies in predicting CVC insertion complications.
8. What is the most effective skin disinfectant in preventing central line infections?
See page 5 of the written guide.
Chaiyakunapruk N, Veenstra DL, Lipsky BA, Saint S. Chlorhexidine compared with povidone-iodine solution for vascular catheter-site care: a meta-analysis. Ann. Intern. Med. 2002 Jun 4;136(11):792–801.
9. Which of the following insertion sites is generally the most suitable site for a CVC insertion during CPR?
It is a matter of physical access. The top end of the patient tends to be crowded. There was even an RCT of IJ v Femoral insertion during CPR that found it took less time and was more successful to aim for the femoral vein.
10. Which of the following statements with regards to ultrasound is false?
Don't be fooled. BART — Blue, Away; Red, Towards so it depends on the orientation of your probe relative to the direction of flow of blood in the artery. Note also, even BART can be reversed in the preferences of some ultrasound machines.
11. Which of the following organisms is least likely to cause a catheter related blood stream infection?
Most central line infections are caused by gram positive bacteria and, to a lesser degree, fungi. Gram negative line infections are rare.
12. As compared with the unsheathed introducing needle, the catheter-on-needle supplied in the Arrow™ CVC kit is generally:
Most prefer to use an unsheathed introducing needle to cannulate the vein and advance the needle through. It is stiffer and easier to manipulate, especially deeper in soft tissue. If it is your preference you should be aware of the risk of fracturing the guide wire if you retract it through the the unsheathed needle.
13. When positioning a patient for an internal jugular vein CVC insertion, what is the ideal amount of patient head rotation?
I commonly see trainees rotating the head too far away from the site of insertion. Ultrasound research shows that this reduces the diameter of the internal jugular vein.
14. As compared with CICCs, PICCs are associated with:
There is a common misconception that PICCs are safer than CVC. When studied with similar patient groups PICCs are associated with higher rates of thrombophlebitis and DVTs, and a similar rate of line infections.
15. In assessing a patient for CVC insertion, which of the following examination findings is least important?
Atrial fibrillation has no baring on the risks of CVC insertion and insertion site preference.
16. What is the most appropriate step in managing inadvertent catheterisation of of an artery?
Once an artery has been dilated the vessel is going to need a surgeon to fix the damage. External pressure is unlikely to be enough.
17. Which of the the following are least likely to indicate malplacement?
Ectopic beats on the ECG can be a sign that you are touching the myocardium and may be on the right track. Best retract the wire a bit though.
18. Which of the following is the lest reliable in detecting an accidental arterial puncture?
All 4 options are useful. Ultrasound is prone to mistaken misidentification of an artery which may be why the artery was cannulated in the first place. My preferred method, for what it is worth is fluid column analog manometry.
19. Which of the following is the least appropriate for aggressive fluid resuscitation?
PICCs have a long and narrow lumen and have very slow flow rates. PICCs are terrible for rapid fluid resuscitation. Multi-lumen CVCs are better but not ideal. Central vein sheath and rapid infusion catheters are ideal for rapid infusions.
20. Which of the following signs indicates a suitable clinical area to perform a CVC insertion?
You should be looking for the international sign for a "cardiac protected area."
21. A suitable insertion point on the femoral vein is typically:
The insertion point should definitely be inferior to the level of the inguinal ligament to avoid the potential of a bleed into a non tamponading space (the retroperitoneum). The junction with the superficial epigastric vein is usually at the level of the inguinal ligament. The position of maximal pulsation is a traditional landmark but it is inferior to ultrasound guidance. The junction with the great saphenous vein is safely inferior to the inguinal ligament.
22. The axillary vein becomes the subclavian vein:
23. As compared with chlorhexidine based solutions, povidone-iodine solutions are associated with aproxomately:
This is a big deal. Use chlorhexidine unless you have a good reason not to.
24. Reserve your dominant hand for:
25. As compared with a standard syringe, the hollow blue syringe (Raulerson syringe) that is supplied in the Arrow™ CVC kit makes it easier to:
The Raulerson syringe has many drawbacks but I do not use it mainly because I do not want to feed the guide wire without disconnecting needle from syringe. I want to see what colour the blood coming out of the patient is and how it is flowing. Without this advantage it holds no appeal.
26. In the absence of allergies, which of the following is suitable for proceduralist hand washing prior to CVC insertion?
Chlorhexidine and alcohol are great at killing gram positive bacteria!
27. The axillary vein is a direct continuation of which vein?
28. Which of the following is not an advantage of right over left sided internal jugular CVC insertion?
Most factors favour a right sided approach, especially if the proceduralist is right hand dominant. One might expect the wire to advance into the heart more often on the right but this is not born out in clinical trials.
29. Which of the following is considered a microshock?
See the written guide.
30. What is the typical rate of catheter-related bloodstream infections in a general ICU population?
Most units used to achieve rates of CVC infection up around 8 per 1000 catheter-days. Now that we take the risk of line infection more seriously and are more careful about sterility most units achieve a rate closer to 2 per 1000 catheter-days.
31. Which of the following is the most reliable sign of successful venous, rather than arterial, cannulation?
Ultrasound can fail in two ways. The wire can traverse the vein into the artery and an ultrasound check will mistakenly reassure. A vein can be confused with artery just as much at the post-wire-isertion stage as during initial cannulation. A flat pressure wave form can arise when a cannula is within the artery but up against the vessel wall.
32. Choose the least suitable site for a central line insertion in a patient with severe liver failure.
The concern here is coagulopathy and, mainly, thrombocytopenia. If a patient has a significant bleeding tendency the subclavian should be the vein of last resort.
