The Effect of Liver Regeneration on Resting Energy Expenditure After Liver Resectional Surgery

Penetrating liver injury occurs commonly in victims of battlefield trauma. It is associated with a high mortality and morbidity rate. Management of liver injury is complex and challenging and can often involve debridement or anatomical resection of liver tissue.

Following liver resection, the liver regenerates to its original volume. Liver regeneration involves complex metabolic processes and maximal regeneration occurs over the first post operative week. This process is highly energy dependent and adds a further burden on post operative energy and therefore nutritional requirements.

Inadequate post-operative nutrition is associated with poorer outcomes and complication rates. Additionally, over feeding is also associated with adverse outcome. The actual additional energy expenditure involved in liver regeneration is not currently known and therefore accurate calorific balance remains a challenge.

The measurement of energy expenditure in these patients is therefore important. Traditionally energy expenditure has been measured by indirect calorimetry and doubly labelled water. These techniques require skilled operators and are often impractical for everyday clinical usage and impossible in the deployed setting.

A recent development is a lightweight armband that measures total and resting energy expenditure. It has been validated against the gold standard techniques in various settings including cancer cachexia, obesity and healthy volunteers and is deemed highly acceptable also. It has not been validated in the unique setting of liver regeneration.