Strategies used for the withdrawal of humidified high flow nasal cannulae (HHFNC) in preterm infants

Background: Humidified high flow nasal cannula (HHFNC) is a form of respiratory support used in the treatment of preterm infants. Potential risks of HHFNC include damage to the nose and leaking of air from the lungs. Infants on HHFNC require more nursing care and the use of extra equipment (when compared to not being on any support). However, potential complications of removing HHFNC from babies too early include increased episodes of forgetting to breathe, increased oxygen needs, increased effort of breathing, the need to restart HHFNC, and the need for a breathing tube with mechanical ventilation. Any of these complications can be seen as a "failure" and are potentially distressing to staff and family. The best way to withdraw HHFNC once it has been started is unknown. Options include simply stopping, weaning the flow, increasing the time off HHFNC each day, or combinations of both.

Study question :What are the benefits and risks of different strategies used for the withdrawal of HHFNC in preterm infants who are stable and may be ready to have HHFNC withdrawn?

Study characteristics and key findings:Researchers from Cochrane searched for all available literature up to 30 March 2015. We did not identify any eligible studies looking at the best strategy to wean or withdraw HHFNC once started as respiratory support in preterm infants for inclusion in this Cochrane review.

Conclusions: The best strategy for weaning, or withdrawal, or both, of HHFNC used as a form of respiratory support in preterm infants remains unclear. Studies are required to answer these questions. Clear criteria are needed to establish a definition of stability prior to attempting to withdraw HHFNC, and for failure to withdraw/wean HHFNC.

Authors' conclusions: 

There is currently no evidence available to suggest the best strategy for weaning and withdrawing HHFNC as a respiratory support in preterm infants. Research is required into the best strategy for withdrawal of HHFNC and to which subgroups this applies. Clear criteria for the definition of stability prior to attempting to withdraw HHFNC needs to be established. Furthermore, clear definitions are needed as to what constitutes failure of HHFNC.

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Background: 

Humidified high flow nasal cannula (HHFNC) delivers humidified gas at increased flow rates via binasal prongs and is becoming widely accepted as a method of non-invasive respiratory support for preterm infants. While indications for the use of (HHFNC) and its associated risks and benefits are being investigated, the best strategy for the discontinuation of HHFNC remains unknown. At what point an infant is considered stable enough to attempt to start withdrawing their HHFNC is not known. The criteria for a failed attempt at HHFNC discontinuation is also unclear.

Objectives: 

To determine the risks and benefits of different strategies used for the discontinuation of HHFNC in preterm infants.

Search strategy: 

We searched the Cochrane Neonatal Review Group Specialized Register, PubMed (1966 to March 2015), CINAHL (1982 to March 2015), EMBASE (1980 to March 2015), and the Cochrane Central Register of Controlled Trials (CENTRAL). Also, we checked previous reviews, including cross references. We searched for following web sites for ongoing trials: ClinicalTrials.gov and controlled-trials.com.

Selection criteria: 

We included randomised controlled trials (RCTs) and quasi-RCTs in which either individual newborn infants or clusters of infants (such as separate neonatal units) were randomised to different HHFNC withdrawal strategies (from the first time they come off HHFNC and any subsequent weaning, or withdrawal attempt, or both).

Data collection and analysis: 

We used standard methods of Cochrane and the Cochrane Neonatal Review Group.

Main results: 

We identified no eligible studies examining the best strategy to wean or withdraw HHFNC once started as respiratory support in preterm infants