This chapter is vaguely relevant to Section G7(iii)  of the 2017 CICM Primary Syllabus, which asks the exam candidate to "describe the invasive and non-invasive measurement of blood pressure, including
limitations and potential sources of error".
It is also vaguely related to Section X(ii), "describe the anatomy relevant to the insertion of an arterial line into a brachial, axillary, posterior tibial, dorsalis pedis, radial or femoral artery". None of the Part I or Part II questions have so far tested the candidate's ability to wisely select a correct insertion site, perhaps recognising that there are many different ways to skin a cat.

There is no specific literature to guide decisionmaking in this area. Most of the material presented here is derived from "Chapter 3: Arterial line placement and care" from  Irwin and Rippe's Intensive Care Medicine (7th Ed), by  Lee-Llacer and Seneff. Site selection is guided as much by the effects we don't want as by the desired effects, and valuable reading about site-specific complications should include the excellent reviews by (Scheer et al, 2002; Frank et al,1983).

In short:

The ideal site for arterial catheter placement would have the following characteristics:

  • Large
  • Proximal
  • Extensive collateral circulation
  • Comfortable for the patient
  • Accessible for nursing care and insertion
  • Unaffected by infection or trauma
  • Not in the way of any other planned procedure (eg. a radial artery harvest for CABG)
  • Close to the monitoring equipment (if it cannot be repositioned)

Potential sites typically used in adults include:

  • Radial artery
  • Femoral artery
  • Axillary artery
  • Dorsalis pedis artery
  • Brachial artery

Less typical sites can include:

  • Ulnar artery
  • Axillary artery
  • Superficial temporal artery

However, everyone still ends up getting a radial arterial line. This is because the balance of risk and benefit favours the radial artery as the first choice for arterial catheterisation. Each site has its advantages and disadvantages, with respect to ease of nursing access, patient comfort, accuracy of measurement and difficulty of cannulation; and rates of serious complications are similar for all sites.

In the neonatal setting, the umbilical artery is a unique access point which also needs to be mentioned. Theoretically, any peripheral artery can be accessed for arterial pressure measurement.


Lee-Llacer J, Seneff, M. "Chapter 3: Arterial line placement and care." In: Irwin and Rippe's Intensive Care Medicine, 7th Edition.  New York: Little, Brown (2007): 36-47.

Pauca, Alfredo L., et al. "Does radial artery pressure accurately reflect aortic pressure?." Chest 102.4 (1992): 1193-1198.

Russell, James A., et al. "Prospective evaluation of radial and femoral artery catheterization sites in critically ill adults." Critical care medicine 11.12 (1983): 936-939.

Scheer, Bernd Volker, Azriel Perel, and Ulrich J. Pfeiffer. "Clinical review: complications and risk factors of peripheral arterial catheters used for haemodynamic monitoring in anaesthesia and intensive care medicine." Critical Care 6.3 (2002): 199.

Thomas, Frank, et al. "The risk of infection related to radial vs femoral sites for arterial catheterization." Critical care medicine 11.10 (1983): 807-812.