KDIGO Clinical Practice Guideline for Acute Kidney Injury
Total Energy Intake: Recommendations and Rationale

• 3.3.2:We suggest achieving a total energy intake of 20–30 kcal/kg/d in patients with any stage of AKI. (2C)

Rationale

Carbohydrate metabolism in AKI is characterized by hyperglycemia due to peripheral insulin resistance^158,159 and accelerated hepatic gluconeogenesis, mainly from conversion of amino acids released during protein catabolism that cannot be suppressed by exogenous glucose infusions.¹⁶⁰ In addition, hypertriglyceridemia commonly occurs due to inhibition of lipolysis. The clearance of exogenously administered lipids can be reduced.¹⁶¹ The modifications of energy metabolism are usually not caused by AKI per se but related to acute comorbidities and complications.¹⁶² Energy consumption is not increased by AKI. Even in multiple-organ failure, the energy expenditure of critically ill patients amounts to not more than 130% of resting energy expenditure. The optimal energy-to-nitrogen ratio during AKI has not been clearly determined. In a retrospective study of AKI patients undergoing continuous venovenous hemofiltration (CVVH), less negative or weakly positive nitrogen balance was associated with an energy intake of approximately 25 kcal/kg/d.¹⁶³ In a randomized trial in AKI patients comparing 30 and 40 kcal/kg/d energy provision, the higher energy prescription did not induce a more positive nitrogen balance but was associated with a higher incidence of hyperglycemia and hypertriglyceridemia and a more positive fluid balance.¹⁶⁴ These observations provide a rationale to maintain a total energy intake of at least 20, but not more than 25–30 kcal/kg/d, equivalent to 100–130% of resting energy expenditure. Energy provision should be composed of 3–5 (maximum 7) g per kilogram body weight carbohydrates and 0.8–1.0 g per kilogram body weight fat.