Der Einfluss unterschiedlichen PEEP-Niveaus (PEEP 5 versus PEEP 10 cm H2O) bei kontrollierter Beatmung und druckunterstützter Spontanatmung auf die Zytokinliberation beim induzierten Lungenversagen

Mechanical ventilation ( MV) is the mainstay of therapy for acute lung injury. As a result of an improved understanding that mechanical ventilation itself can contribute to and aggravate the disease process, the term ventilator- associated lung injury has been introduced. Exemplary there is a high risk of barotrauma- and volutrauma if using high airway pressures or high tidalvolume for recruting atelectatic lung areas. The main objective of a ventilation strategy is the recruitment of atelectasis in order to improve gas exange an prevent the atelectrauma. This atelectrauma can be attenuated by increasing positive endexspiratory pressure ( PEEP). Lung protective ventilation is accepted as a proven therapy and the use of ideal PEEP as well as spontaneous breathing during controlled ventilation are common therapy. One of the underlying mechanisms is the biotrauma, an inflammatory response in which cytokines play a important role. MV can upregulate pulmonary cytokines production and involves in the systemic circulation and may result in multiple organ dysfunction syndromes. It is much known about the interaction of PEEP during controlled and spontaneous ventilation. How the systemic cytokinrelease depends on the PEEP Level is the subject of the present study. Acute lung injury was induced at fourty female pigs by means of a broncho-alveolar Lavage with sodium chloride. Afterwards twenty pigs were ventilated for twelve hours with Pressure Support Ventilation ( PSV) and controlled ventilation ( CMV) with a PEEP of 5 respectively 10 cm H²O. The influence of PEEP on hemodynamic parameters, gas exange , ventilation-perfusion distribution and the sytemic cytokine release in the serum plasma of interleukin ( IL) 8, IL-10 und TNF-Alpha were messured. The investigation has shown, that there was no improvement of the messured cytokines- and chemokinparameters in the groups ventilated with a PEEP of 5 or 10 H²O. There was no significantly decrease or increase of the inflammatory response. The results suggest, that Spontaneous breathing excursions lead to no additional mediator release, but there are more studies necessary to verify these findings