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

UNLABELLED: The use of volume guarantee (VG) on high-frequency oscillatory ventilation (HFOV) allows to use fixed very low high-frequency tidal volume (VThf), maintaining adequate CO2 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 PaCO2). 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 CO2 removal reduces lung injury in a neonatal animal model of lung injury after prolonged mechanical ventilation with HFOV combined with VG.