Noninvasive Continuous Positive Airway Pressure by Helmet or Facial Mask in Children: a Multicenter Randomized Controlled Study

Prospective, randomized, multicenter clinical study on parallel groups involving all consecutive infants ageing >1 month <2 yrs, admitted to PICU at Fondazione IRCCS Ca'Granda Ospedale Maggiore Policlinico, Children Hospital V. Buzzi Milan, and at Gemelli Università Cattolica del Sacro Cuore Rome, for mild to severe acute respiratory failure (ARF). For screening purposes ARF is defined as the presence of all the following: respiratory rate >50 breaths/min; Partial arterial Oxygen tension/Inspired Oxygen Fraction ratio (PaO2/FiO2) <300, chest x-ray compatible with clinical diagnosis, no significant clinical improvement after breathing oxygen at 8 l/min or more for at least 15 min.

Before enrollment patients receive standard medical therapy consisting of oxygen administration via Venturi mask to achieve a peripheral oxygen saturation (SpO2)> 92% and medications including aerosolized salbutamol or adrenaline, anticholinergic, steroids, intravenous antibiotics, correction of electrolytes, and intravascular volume abnormalities as clinically indicated. Heart rate, systemic arterial blood pressure, respiratory rate, and SpO2 are continuously monitored. Patients are defined as requiring NCPAP if they deteriorate despite medical treatment and meet at least one of the following criteria: SpO2<90% with FiO2 > 40%, arterial pH < 7.25, respiratory rate > 50 breaths/min, severe deterioration in mental status (Glasgow Coma Scale < 10). Eligible patients meeting two or more of the above criteria are randomly assigned to receive NCPAP either by full-face mask or by helmet. Random assignment is made by sealed envelopes. Informed consent is obtained from at least one parent or a legal guardian before the enrollment in the study.

To facilitate tolerance up to a maximum of 2 boluses of midazolam 0.1 mg/kg intravenous can be administered eventually followed by an intravenous continuous infusion rate, according to the attending physician's discretion. Once the interface is positioned, a baseline CPAP level is set at 4 cm H2O and then raised in increments of 2 cm H2O every 20 min up to a maximum of 10 cm H2O to improve respiratory performance as evidenced by oxygen need, respiratory rate decrease and the reduction of accessory muscles activity. Inspired Oxygen Fraction (FiO2) is set to achieve a SpO2≥ 92%. NCPAP is administered intermittently for at least 8 hours a day for the first 48 hours after enrollment, but the daily administration can last longer if well tolerated or less if either weaning or intubation criteria are achieved. In case of persistent intolerance to the interface despite sedative administration, the alternate interface can be used before considering tracheal intubation. For patients with a nasogastric tube a seal connector in the lower rigid part of the helmet or in the dome of the mask are used to avoid air leaks. All patients are kept in semirecumbent position.

Criteria for weaning NCPAP can be discontinued if infants show normal mental status, stable haemodynamics, SpO2>94% in room air and no activation of accessory muscles or paradoxical abdominal motion.

Criteria for endotracheal intubation The predetermined criteria for endotracheal intubation NCPAP administration, despite the use of NCPAP, any hemodynamic or electrocardiographic instability; inability to improve dyspnea, conditions requiring intubation either to protect the airways or to manage copious tracheal secretions.