Nasal high-frequency oscillatory ventilation and CO2 removal: A randomized controlled crossover trial.

OBJECTIVE: To compare short-term application of nasal high-frequency oscillatory ventilation (nHFOV) with nasal continuous positive airway pressure (nCPAP). WORKING HYPOTHESIS: nHFOV improves CO2 removal with respect to nCPAP in preterm infants needing noninvasive respiratory support and persistent oxygen supply after the first 72 h of life. STUDY DESIGN: Multicenter non-blinded prospective randomized crossover study. PATIENT SELECTION: Thirty premature infants from eight tertiary neonatal intensive care units, of mean ± SD 26.4 ± 1.8 weeks of gestational age and 921 ± 177 g of birth weight. METHODOLOGY: Infants were randomly allocated in a 1:1 ratio to receive a starting treatment mode of either nCPAP or nHFOV delivered by the ventilator CNO (Medin, Germany), using short binasal prongs of appropriate size. A crossover design with four 1-h treatment periods was used, such that each infant received both treatments twice. The primary outcome was the mean transcutaneous partial pressure of CO2 (TcCO2 ) value during the 2-h cumulative period of nHFOV compared with the 2-h cumulative period of nCPAP. RESULTS: Significantly lower TcCO2 values were observed during nHFOV compared with nCPAP: 47.5 ± 7.6 versus 49.9 ± 7.2 mmHg, respectively, P = 0.0007. A different TcCO2 behavior was found according to the random sequence: in patients starting on nCPAP, TcCO2 significantly decreased from 50.0 ± 8.0 to 46.6 ± 7.5 mmHg during nHFOV (P = 0.001). In patients starting on nHFOV, TcCO2 slightly increased from 48.5 ± 7.8 to 49.9 ± 6.7 mmHg during nCPAP (P = 0.13). CONCLUSIONS: nHFOV delivered through nasal prongs is more effective than nCPAP in improving the elimination of CO2 .

Efficacy of a new technique - INtubate-RECruit-SURfactant-Extubate - "IN-REC-SUR-E" - in preterm neonates with respiratory distress syndrome: study protocol for a randomized controlled trial.

BACKGROUND: Although beneficial in clinical practice, the INtubate-SURfactant-Extubate (IN-SUR-E) method is not successful in all preterm neonates with respiratory distress syndrome, with a reported failure rate ranging from 19 to 69 %. One of the possible mechanisms responsible for the unsuccessful IN-SUR-E method, requiring subsequent re-intubation and mechanical ventilation, is the inability of the preterm lung to achieve and maintain an "optimal" functional residual capacity. The importance of lung recruitment before surfactant administration has been demonstrated in animal studies showing that recruitment leads to a more homogeneous surfactant distribution within the lungs. Therefore, the aim of this study is to compare the application of a recruitment maneuver using the high-frequency oscillatory ventilation (HFOV) modality just before the surfactant administration followed by rapid extubation (INtubate-RECruit-SURfactant-Extubate: IN-REC-SUR-E) with IN-SUR-E alone in spontaneously breathing preterm infants requiring nasal continuous positive airway pressure (nCPAP) as initial respiratory support and reaching pre-defined CPAP failure criteria. METHODS/DESIGN: In this study, 206 spontaneously breathing infants born at 24(+0)-27(+6) weeks' gestation and failing nCPAP during the first 24 h of life, will be randomized to receive an HFOV recruitment maneuver (IN-REC-SUR-E) or no recruitment maneuver (IN-SUR-E) just prior to surfactant administration followed by prompt extubation. The primary outcome is the need for mechanical ventilation within the first 3 days of life. Infants in both groups will be considered to have reached the primary outcome when they are not extubated within 30 min after surfactant administration or when they meet the nCPAP failure criteria after extubation. DISCUSSION: From all available data no definitive evidence exists about a positive effect of recruitment before surfactant instillation, but a rationale exists for testing the following hypothesis: a lung recruitment maneuver performed with a step-by-step Continuous Distending Pressure increase during High-Frequency Oscillatory Ventilation (and not with a sustained inflation) could have a positive effects in terms of improved surfactant distribution and consequent its major efficacy in preterm newborns with respiratory distress syndrome. This represents our challenge. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT02482766 . Registered on 1 June 2015.

High-frequency partial liquid ventilation in two infants.

Two infants on high-frequency oscillatory ventilation for chronic lung disease and severe respiratory failure, received a bolus of warmed and oxygenated perfluorodecalin up to residual functional capacity, followed by a continuous infusion of 6 ml/kg/hour. Our aim was to improve gas exchange without increasing ventilatory-induced lung injury. Heart rate, oxygen saturation, blood pressure, and TcPO(2)/TcPCO(2) were continuously monitored during treatment. Arterial blood gas was evaluated every 3 hours. Both patients showed improvement of gas exchange with a 13.6 and 12.5% reduction of oxygenation index, respectively. High-frequency partial liquid ventilation is an experimental ventilation technique that could be considered as rescue treatment, to improve oxygenation in subjects with critical respiratory failure. This method could probably produce less damage, than other ventilation modes, to severely injured lungs.