Understanding intestinal circulation - Many barriers, many unknowns

Intestinal macro and microcirculation play an important role in homeostasis. Intestinal microcirculation is regulated by multiple regional and systemic factors which have dynamic interactions. Intestinal circulation is compromised in critical illness such as haemorrhage and sepsis. Consequently, intestinal hypoperfusion may complicate into multi-organ dysfunction syndrome. Intestinal circulation is also vulnerable during the perioperative period of some high risk surgery. In humans, the effects of anaesthetic agents and techniques on intestinal microcirculation remain unknown. Some recent research studies have focused on anaesthesia interactions with intestinal circulation during haemorrhage, sepsis and intestinal ischaemia/reperfusion injury. However, experimental studies of intestinal circulation are difficult to conduct and have produced controversial results. Therapeutic options to optimize intestinal circulation are also limited by many barriers such as the disparity between the circulation of other splanchnic organs and systemic haemodynamics.