When babies can't breathe effectively, we can use a facemask to give them breaths and oxygen. There are various types of facemasks that can be used, including round and anatomical (triangular) masks, depending on the preference of the hospital, but it is unclear if one is better for the baby. Both types of facemasks are recommended in international guidelines, without any advice whether one is better than the other. Previous studies published by our research group demonstrated that a variety of different masks are used around the hospitals in Ireland. If a lot of air is leaking around the mask, it means that the baby is not getting the full breathing support that we are trying to give. We currently do not have enough evidence to say which type of mask is better to reduce the risk of this potential leaking of air.

Recent studies have suggested that holding a mask with two hands (instead of one) is better in round facemasks. The combination of an anatomical mask and a two-handed hold has not yet been studied in babies.

In this study, we will compare two different facemasks (round and anatomical) when holding the mask on a baby's face with two hands to help them breathe. We will randomly allocate each baby to either a round mask or an anatomical (triangular) mask and we will measure how much air leaks out around the mask during each breath. We will do this in babies who are in the neonatal unit.

Delivering effective facemask ventilation is an essential component of neonatal resuscitation. However, facemask leak of up to 60% in preterm neonates and airway obstruction are common and can be associated with ineffective ventilation of the baby and clinical instability (O'Currain 2019). Multiple characteristics may influence the effectiveness of facemask ventilation, such as operator technique, infant gestation, airway anatomy and tone, as well as facemask size and shape.

The Neonatal Resuscitation Programme (NRP) allows for either type of facemask as per local practice, without recommending a particular shape of that facemask. A recent national airway survey by our group demonstrated that 8/19 centres in Ireland use both anatomical and round facemasks in clinical practice, with 11 different sizes and shapes of facemasks in clinical use in neonatal units in Ireland. While studies to date have not found a difference between anatomical and round masks in neonatal manikins, these studies only included facemask ventilation delivered with a one-handed hold, rather than a two-handed hold. Emerging evidence, including benchtop and clinical data, suggests that a two-handed hold is superior to a one-handed hold in round facemasks. The combination of an anatomical mask and a two-handed hold has not yet been studied in a clinical setting.

This study will compare the measured leak in mask ventilation with a two-handed hold, delivered by a healthcare professional in the neonatal team, using an anatomical versus a round facemask with standardised mask size. The facemasks will be assessed by a randomised controlled trial, with the anatomical mask as the intervention and the round mask as the control. The population that will be studied is neonates in the neonatal intensive care unit (NICU), at any gestation, who the clinical team have decided to intubate. A member of the research team, who will provide an out-of-hours on call service, will attend the event. The relevant outcomes will be measured by the Monivent Neo100, which will be set up by the research team. Standardised mask size, as per local protocol, will be used, with the sensor module placed between the mask and the T-piece with an adaptor. The outcomes will assess the effectiveness of both the intervention and control, including ventilation parameters recorded by the Monivent Neo100 and the clinical stability of the patient. The primary outcome of this study is the percentage mask leak. A research team member will record data for primary and secondary outcomes. The event will be filmed for post-hoc video analysis. The outcome assessor will be blinded to the group allocation.This research project will take place over 10 months, with an interim analysis to ensure recruitment is projected to achieve sample size.

Inclusion Criteria:

• All term and preterm neonates in the neonatal unit who the clinical team have decided to intubate, with or without pre-medication, and who require mask ventilation prior to intubation attempt.

Exclusion Criteria:

• Neonates with a congenital malformation that would impact mask seal will not be included.

Data will be pseudononymised and will be presented/shared only as collated values, as opposed to individual results.

This is an unblinded study as it is not possible to blind the provider to the type of facemask used. However, the operators will be blinded to the respiratory function monitor measurements feedback. This will be achieved by obscuring the colour sensor with an opaque covering and covering the Monivent screen. The outcome assessor will be blinded to the group allocation.