The systemic response to surgery

The local effects of surgery on tissue and organ systems are usually evident to the surgeon; however, the trauma of surgery itself leads to a generalized physiological response. The systemic response to surgery encompasses a wide range of interlinked endocrinological, metabolic and immunological pathways. Although some of these mechanisms can be protective, the systemic response to surgery can lead to the development of the systemic inflammatory response syndrome (SIRS). This article will describe in detail the hormonal, metabolic and immunological response to surgery. It will also discuss the modulation of the response by agents used in anaesthesia and give examples of specific surgical factors that can alter the systemic surgical response.