View clinical trials related to Positive Expiratory Pressure.
Filter by:The induction of general anaesthesia is associated with a fall in lung volume due in particular to a decrease in muscle tone and the formation of denitrogenation atelectasis. Many recent studies insist on the need to apply a so-called "protective" strategy of intraoperative ventilation, which combines the use of recruitment manoeuvres, reduced tidal volume (Vt) (6-8ml/kg) and positive expiratory pressure (PEEP) to prevent these phenomena. However, the setting of PEEP remains debated and several authors agree on the need to individualize ventilatory parameters, particularly in obese patients, without describing the individualization tools. In the ICU, it has been shown that electrical impedance tomography (EIT) can be used to individualise the PEEP level in a simple and non-invasive way. Therefore, we wish to determine whether the use of this technique during general anaesthesia allows for the individualization of PEEP, and whether the value determined is correlated with the body mass index (BMI).
Determination of the best positive end-expiratory pressure (PEEP) based on oxygenation or driving pressure in patients with acute respiratory distress syndrome (ARDS) after cardiothoracic surgery The use of a positive end-expiratory pressure in acute respiratory distress syndrome is obvious in ARDS management. On the one hand it serves to fight against the reduction of functional residual capacity (FRC) and enable the limitation of hypoxia; and on the other hand it allows the limitation of "opening/closing" lesions in pulmonary alveoli which lead to increase "bio trauma". However elevated PEEP has harmful effect such as hemodynamic effect on the right ventricle and distension on healthy part of the lung.Other adverse effects are: decreasing cardiac output, increased risk of barotrauma, and the interference with assessment of hemodynamic pressures. Ideally the adjustment of PEEP level must be done by taking into account each patient characteristic. PEEP titration based on blood gas analysis is one of the most used techniques by physicians. Current guidelines for lung-protective ventilation in patients with acute respiratory distress syndrome (ARDS) suggest the use of low tidal volumes (Vt), set according to ideal body weight (IBW) of the patient, and higher levels of positive end-expiratory pressure (PEEP) to limit ventilator-induced lung injury (VILI). However, recent studies have shown that ARDS patients who are ventilated according to these guidelines may still be exposed to forces that can induce or aggravate lung injury. Driving pressure (DP) is the difference between the airway pressure at the end of inspiration (plateau pressure, Ppl) and PEEP. Driving pressure may be a valuable tool to set PEEP. Independent of the strategy used to titrate PEEP, changes in PEEP levels should consider the impact on driving pressure, besides other variables such as gas exchange and hemodynamics. A decrease in driving pressure after increasing PEEP will necessarily reflect recruitment and a decrease in cyclic strain. On the contrary, an increase in driving pressure will suggest a non-recruitable lung, in which overdistension prevails over recruitment. The main purposes of this study are to assess the optimal PEEP based on the best driving pressure or the best oxygenation.