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Who is nasal high flow for - general principles and published guidelines.

The short answer is patients breathing on their own (who don’t require immediate mechanical ventilation) with or at risk of respiratory distress, i.e., patients presenting with:

respiratory rate


High work
of breathing

Low SpO2

High PaCO2


  • In an acute setting (Emergency Department or Intensive Care Unit), clinicians typically view NHF as a way of meeting or exceeding a patient’s inspiratory demand, so the work of breathing is reduced in patients experiencing respiratory distress – delivering a controlled amount of oxygen to patients with comfort and convenience.
  • ​In a chronic setting (respiratory floor/ward, long-term care facility, or home), clinicians may (for example) prescribe NHF primarily to help a patient with secretion clearance and secondarily to provide respiratory support.

Top tips: 

  1. Understand the mechanisms of action - this will help you recognize patients who will benefit from NHF therapy. 
  2. Keep up to date with the guidelines - patient groups proven to benefit from NHF are identified in emerging clinical practice guidelines; see below. 

Evidence-based clinical practice guidelines

Hundreds of randomized controlled trials have been consolidated into clinical practice guidelines. 

These guidelines underscore the breadth of application of nasal high flow therapy.

We’ve created a table that will help you review the  guidelines by patient population and application.


Explore the NHF guidelines table