[Intraoperative Ventilation]

Mechanical ventilation is mandatory for general anesthesia. Thereby, many parameters have to be chosen wisely by the anaesthesist. Essentials are the peak pressure, which should be below 30 mmHg and the PEEP (positive endexpiratory pressure) - in healthy adults at least 5 mmHg. The driving pressure is the pressure difference between the plateau-pressure and the PEEP. The driving pressure has a higher association with postoperative pulmonary complications than the peak pressure and should be below 15 mmHg. The tidal volume for the patient should be calculated with 6 to 8 ml per kg ideal body weight. High inspiratory oxygen causes atelectasis and for the emergence of anesthesia 0,6 to 0,8 FiO₂ should be considered. Atelectasis develops during every general anesthesia, nevertheless recruitment can not be recommended generally since it can damage the lung in the sense of a volume- or barotrauma. There is no statistical significant difference between pressure and volume controlled ventilation based on postoperative pulmonary complications. During a reanimation, volume-controlled ventilation is beneficial because of the high variation of the necessary pressure needed to apply a constant tidal volume. The inspiratory flow is an indication for the speed with which the volume is administered into the lung. High inspiratory flows can damage the lung and are often underestimated. Mechanical ventilation is necessary but has the potential to harm the lung. Every single parameter has to be chosen carefully and the ventilation chosen and adapted individually for each patient in different operation setting with changing requirements.