Fluid administration device flow rates

Reviewed and revised 26 July 2015


  • rapid fluid administration is potentially life-saving in the resuscitation setting
  • flow rates achieved depend on the devices used in fluid administration, largely in agreement with Poiseuille’s law


Figure from Reddick et al, 2011


General rules of thumb

  • a large bore cannula is preferable to a narrow bore cannula
  • a shorter cannula is preferable to a longer cannula
  • a larger proximal vein is preferable to smaller distal vein
  • upper limbs are preferable to lower limbs, especially in CPR

Choice of vascular access

  • a peripheral cannula of size 18G or greater is preferable to infusion by central line for rapid fluid delivery
  • if a central line is the only obtainable access then the addition of a pressure bag makes a greater difference to rate of flow than it would with a peripheral cannula
  • An over the needle FEP large-bore cannula inserted into a large vein is likely to give a greater flow rate than a Seldinger type polyurethane catheter and would be preferable if all other factors are equal
  • A needle-free intravenous access connector (a “bung”) should not be used when rapid fluid resuscitation is required as it slows the rate offlow by up to 40% with peripheral cannulae

Intraosseous access

  • Flow rates of 60–100 ml/min of crystalloid, via a 15 gauge tibial intraosseous needle, have been achieved in the adult using the hydraulic pressure of a large syringe, attached to the needle by a three way tap and fed from a standard infusion bag
  • In a resuscitation setting, IO access is preferable to CVC insertion if peripheral vascular access cannot be obtained rapidly
    — higher success rates on first attempt (85% versus 60%, p=0.024)
    — shorter procedure times (2.0 versus 8.0 min, p<0.001)

References and Links

Journal articles

  • Leidel BA, Kirchhoff C, Bogner V, Braunstein V, Biberthaler P, Kanz KG. Comparison of intraosseous versus central venous vascular access in adults under resuscitation in the emergency department with inaccessible peripheral veins. Resuscitation. 2012 Jan;83(1):40-5. PMID: 21893125.
  • Reddick AD, Ronald J, Morrison WG. Intravenous fluid resuscitation: was Poiseuille right? Emerg Med J. 2011 Mar;28(3):201-2. PMID: 20581377.
  • Waisman M, Waisman D. Bone marrow infusion in adults. J Trauma. 1997 Feb;42(2):288-93. PMID: 9042884.

CCC 700 6

Critical Care


Chris is an Intensivist and ECMO specialist at the Alfred ICU in Melbourne. He is also a Clinical Adjunct Associate Professor at Monash University. He is a co-founder of the Australia and New Zealand Clinician Educator Network (ANZCEN) and is the Lead for the ANZCEN Clinician Educator Incubator programme. He is on the Board of Directors for the Intensive Care Foundation and is a First Part Examiner for the College of Intensive Care Medicine. He is an internationally recognised Clinician Educator with a passion for helping clinicians learn and for improving the clinical performance of individuals and collectives.

After finishing his medical degree at the University of Auckland, he continued post-graduate training in New Zealand as well as Australia’s Northern Territory, Perth and Melbourne. He has completed fellowship training in both intensive care medicine and emergency medicine, as well as post-graduate training in biochemistry, clinical toxicology, clinical epidemiology, and health professional education.

He is actively involved in in using translational simulation to improve patient care and the design of processes and systems at Alfred Health. He coordinates the Alfred ICU’s education and simulation programmes and runs the unit’s education website, INTENSIVE.  He created the ‘Critically Ill Airway’ course and teaches on numerous courses around the world. He is one of the founders of the FOAM movement (Free Open-Access Medical education) and is co-creator of litfl.com, the RAGE podcast, the Resuscitology course, and the SMACC conference.

His one great achievement is being the father of three amazing children.

On Twitter, he is @precordialthump.

| INTENSIVE | RAGE | Resuscitology | SMACC

One comment

  1. Thanks for the awesome site. I do have to point out the following though….
    It is not the case that ” flow rates are largely in agreement with Poiseuille’s law”
    It’s clear from looking at the data that the relationship between radius and flow is roughly r^1.5, not r^4. That’s a huge difference.
    A 22g piv has a higher flow rate than a 18g cvc, even though the internal radius of a 22g is about half of a 18g. Length trumps radius in that regard. Poiseuille’s law doesn’t apply to turbulent flow, which starts around 1-10m/s. These fluids are moving > 50m/s
    We should stop teaching Poiseuille’s law. It doesn’t apply.


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