View clinical trials related to Ventilator-Induced Lung Injury.
Filter by:The purpose of this study is to determine, in preterm infants less than 37 weeks gestation with respiratory distress who are ventilated in the first 48 hours after birth, if mid frequency ventilation strategy using ventilator rate of ≥ 60 to ≤ 150 per minute compared with standard frequency ventilation strategy using ventilator rates of ≥ 20 to < 60 per minute will increase the number of alive ventilator-free days after randomization and reduce the risk of ventilator induced lung injury.
Lung protective ventilation (LPV) has been proposed to reduce the incidence of postoperative pulmonary complications (PPCs), and protect against ventilator induced lung injury (VILI).
The use of positive end-expiratory pressure (PEEP) has been shown to prevent the cycling end-expiratory collapse during mechanical ventilation and to maintain alveolar recruitment, keeping lung portions open, increasing the resting end-expiratory volume. On the other hand PEEP may also overdistend the already open lung, increasing stress and strain. Theoretically high frequency oscillatory ventilation (HFOV) could be considered an ideal strategy in patients with ARDS for the small tidal volumes, but the expected benefits have not been shown yet. PEEP and HFOV should be tailored on individual physiology. Assuming that the esophageal pressure is a good estimation of pleural pressure, transpulmonary pressure can be estimated by the difference between airway pressure and esophageal pressure (PL= Paw - Pes). A PL of 0 cmH2O at end-expiration should keep the airways open (even if distal zones are not certainly recruited) and a PL of 15 cmH2O should produce an overall increase of lung recruitment. The investigators want to determine whether the prevention of atelectrauma by setting PEEP and mPaw to obtain 0 cmH2O of transpulmonary pressure at end expiratory volume is less injurious than lung recruitment limiting tidal overdistension by setting PEEP and mPaw at a threshold of 15 cmH2O of transpulmonary pressure. The comparison between conventional ventilation with tidal volume of 6 ml/Kg and HFOV enables us to understand the role of different tidal volumes on preventing atelectrauma and inducing lung recruitment. The use of non-invasive bedside techniques such as lung ultrasound, electrical impedance tomography, and transthoracic echocardiography are becoming necessary in ICU and may allow us to distinguish between lung recruitment and tidal overdistension at different PEEP/mPaw settings, in order to limit pulmonary and hemodynamic complications during CMV and HFOV.
Background: Ventilator induced lung injury (VILI) remains a problem in neonatology. High frequency oscillatory ventilation (HFOV) provides effective gas exchange with minimal pressure fluctuation around a continuous distending pressure and therefore small tidal volume. Animal studies showed that recruitment and maintenance of functional residual capacity (FRC) during HFOV ("open lung concept") could reduce lung injury. "Open lung HFOV" is achieved by delivering a moderate high mean airway pressure (MAP) using oxygenation as a guide of lung recruitment. Some neonatologists suggest combining HFOV with recurrent sigh-breaths (HFOV-sigh) delivered as modified conventional ventilator-breaths at a rate of 3/min. The clinical observation is that HFOV-sigh leads to more stable oxygenation, quicker weaning and shorter ventilation. This may be related to improved lung recruitment. This has however to our knowledge not been tested in a clinical trial using modern ventilators. Purpose, aims: - To compare HFOV-sigh with HFOV-only and determine if there is a difference in oxygenation expressed as a/A-ratio and/or stability of oxygenation expressed as percentage time with oxygen saturation outside the reference range. - To provide information on feasibility and treatment effect of HFOV-sigh to assist planning larger studies. We hypothesize that oxygenation is better during HFOV-sigh. Methods: Infants at 24-36 weeks corrected gestational age already on HFOV are eligible. Patients will be randomly assigned to HFOV-sigh (3 breaths/min) followed by HFOV-only or vice versa for 4 alternating 1-hours periods (2-treatment, double crossover design, each patient being its own control). During HFOV-sigh set-pressure will be reduced to keep MAP constant, otherwise HFOV will remain at pretrial settings. Outcome will be calculated from normal clinical parameters including pulx-oximetry and transcutaneous monitoring of oxygen and carbon-dioxide partial pressures.