A Description of Initial Positive End-Expiratory Pressure Selection in Premature Infants Receiving High-Frequency Jet Ventilation

Background: High-frequency jet ventilation (HFJV) has been utilized as a modality in infants with respiratory distress syndrome who are refractory to conventional ventilation. There is a paucity of data informing initial PEEP selection during HFJV. Therefore, we sought to describe parameters that were associated with PEEP levels following conversion to HFJV. Methods: An IRB approved single-center retrospective review was conducted on subjects who underwent HFJV between 01/2015-01/2019. Subjects were enrolled if birth weight ≤ 2,000 grams and ≤ 34 weeks gestational age. Subjects were excluded if they received HFJV as a first line therapy upon admission. Ventilator parameters and laboratory data were extracted and analyzed prior to HFJV transition and at hours 1, 4, 6 and 12 following conversion. Data included: PEEP, mean airway pressure, FIO2, peak inspiratory pressure (PIP), pH, capillary carbon dioxide level and sigh-breaths. Since the data were not normally distributed, they are reported as median (interquartile range). The Kruskal-Wallis test with Dunn posttest were used in order to evaluate differences in parameters over time. Results: Fifty-three premature subjects (n = 37 male) were studied. Median gestational age was 25.5 weeks (24.1 – 27.8) and birthweight of 900g (695 – 1,555). Subjects received conventional ventilation for a median of 50 hours (13.8 – 218) prior to HFJV; with PIP 20 cm H2O (18 – 24) and frequency 40 breaths/min (38 – 44) respectively. A HFJV frequency of 420 breaths/min and on-time of 0.02 seconds were used for all subjects. A target pH ≥ 7.25 and FIO2 ≤ 0.4 was achieved in 54% and 60% of subjects at four hours, respectively. Ventilator parameters and laboratory data are displayed in Table 1. Conclusions: We observed a statistically significant increase in PEEP, PIP, pH and decrease in PcCO2 compared with baseline. Our findings may inform initial PEEP during conversion to HFJV.