It is well known that certain diseases and patient conditions are associated with increased perioperative risk. The aim of this book is to define and identify the clinical factors that warrant a broader and more detailed assessment of pre-operative surgical risk in difficult and unusual clinical settings. One of the sections is dedicated to the main pathway of peri- and post-surgical critical care based on the patient-specific deterioration risk and associated diseases; here, a panel of selected experts describes the correct patient-oriented pathways for complex or unscheduled surgical operations in order to reduce the operative risk. In addition, the book describes the latest trends in minimally invasive surgical techniques that are associated with peri- and post-operative risk reduction, and provides an overview of recent advances in surgical simulation, focusing on perspectives in surgical research to increase patient safety.