Use of very low tidal volumes during high-frequency ventilation reduces ventilator lung injury

Abstract

The use of volume guarantee (VG) on high-frequency oscillatory ventilation (HFOV) allows to use fixed very low highfrequency tidal volume (VThf), maintaining adequate CO 2 removal while potentially reducing the risk of ventilator-induced lung injury. Objective To demonstrate that the use of very low VThf can be protective compared with standard VThf on HFOV combined with VG in a neonatal animal model. Study design Experimental study in 2-day-old piglets with induced respiratory distress syndrome ventilated with two different HFOV strategies combined with VG (10 Hz with high VThf versus 20 Hz with very low VThf at similar PaCO 2). After 12 h of mechanical ventilation, the pulmonary histologic pattern was analyzed. Results We found in the 10 Hz group with the higher VThf compared with the 20 Hz and very low VThf group more evident and more severe histological lesions with inflammatory infiltrate within the alveolar wall and alveolar space, as well as large areas of parenchyma consolidation and areas of alveolar hemorrhage in the more severe cases. Conclusion The use of very low VThf compared with higher VThf at similar CO 2 removal reduces lung injury in a neonatal animal model of lung injury after prolonged mechanical ventilation with HFOV combined with VG.

Target volume‐guarantee in high‐frequency oscillatory ventilation for preterm respiratory distress syndrome: Low volumes and high frequencies lead to adequate ventilation

“…In this models, HFOV + VG with lower tidal volumes at frequencies as high as 20 Hz led to lower grades of inflammation and VILI compared to standard tidal volumes at 10 Hz after 12 h of mechanical ventilation. 10 T A B L E 2 Mean weight adjusted volumes and standard deviations (SD) for frequencies 13-20 Hz…”

“…3,4 This strategy has proved to better maintain tidal volumes, partial pressure of CO 2 (pCO 2 ) and oxygen saturation, [5][6][7] and although evidence remains unclear, some studies have suggested that VG might lead to lower rates of death and BPD. 8,9 In experimental models, the protective effect of HFOV-VG has been proved when using smaller volumes and very high frequencies, 10 which have been successfully used in preterm newborns in a pilot study. 11 Despite the growing evidence that HFOV-VG could be an alternative for conventional mechanical ventilation in very immature newborns, there are few studies describing which volumes and frequencies lead to adequate ventilation and should initially be set.…”

“…This strategy has proved to better maintain tidal volumes, partial pressure of CO 2 (pCO 2 ) and oxygen saturation, 5–7 and although evidence remains unclear, some studies have suggested that VG might lead to lower rates of death and BPD 8,9 . In experimental models, the protective effect of HFOV‐VG has been proved when using smaller volumes and very high frequencies, 10 which have been successfully used in preterm newborns in a pilot study 11 …”

A low-cost multi-patient pressure-controlled ventilation system with individualized parameter settings

“…An increase in circuit volume might act as a mechanical low-pass filter and reduce the fluctuations. However, it should be considered that some degree of high-frequency oscillation could facilitate expulsion of bronchial secretions [8] and potentially, to some extent, exert the benefits of high-frequency ventilation [9, 10, 11].…”

Surfactant nebulization therapy during NIPPV ventilation in surfactant‐deficient newborn piglets

“…BAL (30 ml/kg; 37°C with F iO2 : 1) was performed to induce SF‐deficient lung injury 20,21 . At the end of BAL procedure, positive pressure ventilation settings were F iO2 = 1.0 21–23 and PEEP = 5 cmH 2 O, and to avoid barotrauma, f R and PIP were adjusted to a maximum of 42 breaths/min and 25 cmH 2 O, to maintain V T = 8–10 ml/kg. Lavage procedures were repeated (every 5 min) until arterial blood partial pressure of oxygen (P aO2 ) <100 mmHg.…”