Children's Hospital of Philadelphia Newborn Care at Pennsylvania Hospital, Philadelphia, PA, USA.
Division of Neonatology, Children's Hospital of Philadelphia, Philadelphia, PA, USA.
J Neonatal Perinatal Med. 2022;15(2):257-263. doi: 10.3233/NPM-210899.
Recent in vitro testing of high frequency (HF) oscillation applied to bubble continuous positive airway pressure (BCPAP) using a novel flow interrupter device (HFI) demonstrated significantly improved CO2 washout while not altering delivered mean airway pressure (MAP) in a premature infant lung model. This study's aim was to evaluate the safety and efficacy of the HFI paired with BCPAP in an animal model of prematurity prior to clinical testing.
DESIGN/METHODS: Twelve fetal lambs, 131-135 days gestation, weight 3.51±0.42 kg, were delivered by Cesarean section. The lambs were supported by mechanical ventilation and weaned to spontaneous breathing with BCPAP at 6 cmH2O. A combined CO2/airflow sensor measured end-tidal (EtCO2) and tidal volume (VT). Blood gases, heart rate (HR), arterial pressure (Part), minute ventilation (MV), MAP, ventilatory efficiency index (VEI), thoracoabdominal phase angle and labored breathing index (LBI) were recorded over a 10-minute baseline period followed by four randomized 10-minute intervals with HFI set to either 8, 10, 12 or 15 Hz.
EtCO2 decreased from baseline by 11.1±2.2SE%, 16.6±4.3SE%, 13.5±4.9SE%, and 19.5±4.5SE% at 8, 10, 12, and 15 Hz respectively (p < 0.001). Blood gases, SpO2, HR, Part, MAP, VT, MV, esophageal pressure, phase angle, and LBI underwent no significant change with HF. Respiratory rate decreased, and VEI increased, by 14.9±4.5SD% (p = 0.037) and 83±22SD% (p < 0.011) respectively, averaged over all frequencies.
We demonstrated the safety and efficacy of a novel BCPAP flow interrupter device. HF applied to the respiratory system resulted in significantly improved CO2 clearance and ventilation efficiency with no deleterious physiological effects in a pre-term lamb model.
最近使用新型流量中断器（HFI）对高频（HF）振荡应用于气泡持续气道正压通气（BCPAP）的体外测试表明，在早产婴儿肺模型中，CO2 冲洗明显改善，而不改变输送的平均气道压力（MAP）。本研究的目的是在临床测试之前，在早产动物模型中评估 HFI 与 BCPAP 联合使用的安全性和有效性。
方法/设计：12 只胎羊，妊娠 131-135 天，体重 3.51±0.42kg，行剖宫产术分娩。羊由机械通气支持，并在 6cmH2O 时用 BCPAP 转为自主呼吸。一个联合的 CO2/气流传感器测量呼气末（EtCO2）和潮气量（VT）。血气、心率（HR）、动脉压（Part）、分钟通气量（MV）、MAP、通气效率指数（VEI）、胸腹壁相位角和呼吸困难指数（LBI）在 10 分钟基线期后记录，然后随机进行四个 10 分钟间隔，HFI 设置为 8、10、12 或 15Hz。
EtCO2 分别下降 11.1±2.2SE%、16.6±4.3SE%、13.5±4.9SE%和 19.5±4.5SE%，分别在 8、10、12 和 15Hz（p<0.001）。血气、SpO2、HR、Part、MAP、VT、MV、食管压、相位角和 LBI 在 HF 期间没有明显变化。呼吸频率下降，VEI 增加 14.9±4.5SD%（p=0.037）和 83±22SD%（p<0.011），平均值为所有频率。
我们证明了新型 BCPAP 流量中断器的安全性和有效性。HF 应用于呼吸系统可显著改善 CO2 清除率和通气效率，而在早产羔羊模型中无不良生理影响。
