ENK Oxygen Flow Delivery System

Reviewed and revised 14 July 2015


  • The ENK oxygen flow delivery system is used in conjunction with emergency cannula cricothyroidotomy


  • emergency oxygen delivery following cannula cricothyroidotomy


  • oxygen supply connector at one end
  • Luer lock connection for attachment to a needle cricothyroidotomy tube at the other end


  • The ENK is connected to the oxygen supply and to the cricothyroidotomy catheter
  • Oxygen flow at 15 L/min or (preferably) higher
  • intermittently covering and releasing the holes in the delivery system by pressing thumb and index finger together allows control of oxygen delivery
  • About 100 cycles per minute is recommended by the manufacturer, however I prefer the approach described by Andy Heard and collleagues:
    • administer the first breath over 4 s (At 15 L/min, or 250 mL/s) this will inflate the lungs with 1L of oxygen; observe for chest rise
    • Subsequent jets (breaths) should be administered over 2 s (i.e. 500 mL). Only give subsequent jets (breaths) when needed: observe the rise in oxygen saturation and wait until the oxygen saturation has fallen by 5% from the maximum achieved. This avoids excessive jetting and reduces the likelihood of barotrauma
    • Wait again for a rise and then 5% fall in SpO2 before delivering subsequent breaths
    • If there is no SpO2 reading for some reason, it is safe to insufflate 500 mls every 30 s
  • unlike a Manujet™ or similar device, the ENK Oxygen Flow Modulator device does not need to be disconnected from the cannula between jets (breaths) to allow expiration
  • ensure decompression occurs in cases of complete airway obstruction


  • failure to chest rise, due to:
    • kinking or displacement of the cannula (stop insufflation, confirm position by aspirating air with a syringe before further ‘jets’)
    • equipment failure or disconnection (check oxygen is on and all connections are intact)
  • barotrauma
  • pneumothorax
  • pneumomediastinum
  • dislodgement (too much pressure can cause the catheter to be ejected from the trachea)
  • hypercapnea (this device allows oxygenation, not ventilation)
  • dynamic hyperinflation


Andy Heard’s video on emergency percutaneous oxygenation techniques

References and Links

Web resources

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

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