Neonatal Noninvasive Ventilation Nasal Mask Interface Pressure and the Inter-Individual Variation of Mask Placement

Background: The 2014 American Academy of Pediatrics recommendation for CPAP as an alternative to mechanical ventilation for treatment of neonatal respiratory distress prompted a rapid shift to noninvasive respiratory support. Since most patients receive nasal bubble CPAP a concomitant increase in nasal pressure injuries followed. This prospective observational study aimed to develop strategies to reduce nasal mask pressure injury in neonates by (1) quantifying CPAP mask-interface pressure and (2) assessing placement variability. Methods: A micro-electromechanical systems pressure sensor was modified for contact pressure measurements with silicone embedding and calibrated. The CPAP generator and interface components were sized for a 24-week neonatal simulator. Thirteen neonatal ICU staff placed the simulator on CPAP at 6 cm H₂O and 8 L/min of flow with no humidification. Pressure was measured at 3 locations (the forehead, nasal bridge, and philtrum) in triplicate (3 measurements/site). Descriptive statistics; a location-specific, one-way analysis of variance with a Tukey post hoc test; and a 2-sample paired t test of the means of the first and last triplicate were performed. Results: Pressure ranged from 12-377.3 mm Hg. The mean [SD] interface pressure at the philtrum was significantly higher than both the nasal bridge and the forehead (philtrum 173.9 [101.3], nasal bridge 67.8 [28.9], and forehead 79.0 [36.9], P < .001). CPAP fixation varied, including bonnet placement, trunk angle, mask compression, use of hook and loop extenders, and level of vigorous bubble feedback achieved. Conclusions: This study developed a modified pressure sensor for quantifying the pressure exerted by a nasal mask on facial skin. Maximum pressures were higher than those previously reported. Inter-individual differences were present in both quantitative and qualitative measures of pressure. Reduction of NIV-associated pressure injuries may be achieved through NIV fixation technique training and improved nasal mask stability and size increments.