A brief report: The use of high-frequency oscillatory ventilation for severe pulmonary contusion

Severe pulmonary contusions are a common cause of acute respiratory distress syndrome (ARDS) and are associated with significant morbidity. High frequency oscillatory ventilation (HFOV) is a ventilatory mode that employs a lung protective strategy consistent with the ARDSNet low tidal volume ventilation strategy and may result in reduced morbidity. The objective of this report is to examine the impact of HFOV on blunt trauma patients with severe pulmonary contusions who failed or were at a high risk of failing conventional mechanical ventilation. Methods: We undertook a retrospective chart review of all patients at our institution who received HFOV for severe pulmonary contusions. Patients were placed on HFOV when their mean airway pressure (mP _aw) surpassed 30 cm H ₂O and their FIO ₂ was greater than 0.6. Baseline demographic data including injury severity score (ISS), length of time requiring HFOV, total ventilator days, and inhospital mortality were collected. Serial determinations of oxygenation index (OI) and the PAO ₂/FIO ₂ ratio (P/F) were made up to 72 hours after initiation of HFOV. A linear mixed model was used to analyze the slope (β) of the regression line of P/F versus time and that of OI versus time. Results: Seventeen patients were identified who underwent HFOV for ARDS due primarily to pulmonary contusions. Mean ISS was 36.6, mean APACHE II score was 21.7, and the mean time before initiation of HFOV was 2.0 days. P/F increased significantly after HFOV was initiated (β = 12.1; 95% confidence interval 7.9 to 16.4, p < 0.001). OI significantly decreased after HFOV implementation (β = 1.8; 95% confidence interval -2.3 to -1.3, p < 0.001). Mortality rate was 17.6%. Conclusions: The early use of HFOV appears to be safe and efficacious in blunt trauma patients sustaining pulmonary contusions, and results in a rapid improvement in OI and the P/F ratio.