Enhanced recovery after surgery protocols for open hepatectomy--physiology, immunomodulation, and implementation.

There has been recent interest in enhanced-recovery after surgery (ERAS®) or "fast-track" perioperative protocols in the surgical community. The subspecialty field of colorectal surgery has been the leading adopter of ERAS protocols, with less data available regarding its adoption in hepato-pancreato-biliary surgery. This review focuses on available data pertaining to the application of ERAS to open hepatectomy. We focus on four fundamental variables that impact normal physiology and exacerbate perioperative inflammation: (1) the stress of laparotomy, (2) the use of opioids, (3) blood loss and blood product transfusions, and (4) perioperative fasting. The attenuation of these inflammatory stressors is largely responsible for the improvements in perioperative outcomes due to the implementation of ERAS-based pathways. Collectively, the data suggest that the implementation of ERAS principles should be strongly considered in all patients undergoing hepatectomy.