Anti-inflammatory Effect of Peroperative Stimulation of the Vagus Nerve

Hypothesis: Electrical stimulation of the abdominal vagus nerve has anti-inflammatory effects which lead to a faster postoperative recovery after abdominal surgery. Aims: In the present study, the investigators want evaluate the anti-inflammatory effect of peroperative electrical stimulation of the vagus nerve. In addition, the investigators want to determine whether vagus nerve stimulation leads to a faster postoperative recovery. To this end, the following aims are formulated: 1. to determine whether vagus nerve stimulation leads to an improvement in gastrointestinal transit using radiological testing 2. to evaluate whether electrical stimulation of the vagus nerve leads to clinical improvement (daily questionnaire) 3. to show that electrical stimulation of the intra-abdominal vagus nerve reduces the inflammatory response to abdominal surgery