Humidified Nasal Prong Oxygen

Arjun Rao Sydney Children’s Hospital, Randwick

Outline

• Terminology • Basic setup • Background • Does it work? • How does it work? • When should I use it? • How to set up? • Transport implications

Terminology

• Humidified • Nasal prong • Oxygen • “High Flow”

– > 1L/kg/min

Basic Setup

Intensive Care Med (2013) 39:247–257

Background

• Initially studied in neonates

PEDIATRICS Vol. 107 No. 5 May 2001

Does it work?

• Depends on our outcome measures • Apnoeas • Work of breathing / physiology • Comparable to CPAP • Reduced intubation • Length of admission

• Flow rate 7L/min generated positive pressure throughout respiratory cycle

• Mean partial pressure and flow correlated • Flow >2L/kg/min -> PP >4cmH20 • Increased flow from 1 -> 7L/min led to

improved work of breathing and decreased RR • Problem of generating PP throughout cycle

with fixed flow

Intensive Care Med (2013) 39:1088–1094

• Retrospective cohort study • HHFNC reduced intubation rate from 16% to

8% • ED intubation rate fell from 11% to 2% • No increased length of ventilation for failed

HHFNC • No mention of use of CPAP

Pediatr Emer Care 2012;28: 1117Y1123

How does it work?

• No definitive mechanism proven • Theories include: • “Washout” of nasopharyngeal dead space • Reduction of upper airway resistance • Positive pressure effects • ? Benefits over CPAP

– Easier setup and monitoring – CPAP may require sedation, problems with nasal

trauma

When should I use it?

• Most studied in infants with bronchiolitis • Infant with respiratory distress secondary to

bronchiolitis • Trial more extended population where access

to PICU/CPAP/Invasive Ventilation more limited

• If no benefit in physiology after 60-90 minutes, then unlikely to be useful

Our set up

Tubing

Heating / Humidifier base

Flow meter

Blender or Y-connector with air/oxygen

Trouble shooting

• Leak around nasal prongs (sizing) • Mouth breathing • Nebulisation port

Transport implications

• NETS ability to transfer • Children < 6kg can possibly be transported on

humidified nasal prong oxygen • Others may need CPAP for transfer • Sedation implications

QUESTIONS?

Summary

• Terminology • Evidence around HHFNC • Practicalities of setup • When to use • Troubleshooting • Transport implications