Refeeding syndrome: relevance for the critically ill patient.

PURPOSE OF REVIEW: To provide an overview of recent findings concerning refeeding syndrome (RFS) among critically ill patients and recommendations for daily practice. RECENT FINDINGS: Recent literature shows that RFS is common among critically ill ventilated patients. Usual risk factors for non-ICU patients addressed on ICU admission do not identify patients developing RFS. A marked drop of phosphate levels (>0.16 mmol/l) from normal levels within 72 h of commencement of feeding, selects patients that benefit from hypocaloric or restricted caloric intake for at least 48 h resulting in lower long-term mortality. SUMMARY: RFS is a potentially life-threatening condition induced by initiation of feeding after a period of starvation. Although a uniform definition is lacking, most definitions comprise a complex constellation of laboratory markers (i.e. hypophosphatemia, hypokalemia, hypomagnesemia) or clinical symptoms, including cardiac and pulmonary failure. Recent studies show that low caloric intake results in lower mortality rates in critically ill RFS patients compared with RFS patients on full nutritional support. Therefore, standard monitoring of RFS-markers (especially serum phosphate) and caloric restriction when RFS is diagnosed should be considered. Furthermore, standard therapy with thiamin and electrolyte supplementation is essential.

Nutrition in the ICU: new trends versus old-fashioned standard enteral feeding?

PURPOSE OF REVIEW: The narrative review aims to summarize the relevant studies from the last 2 years and provide contextual information to understand findings. RECENT FINDINGS: Recent ICU studies have provided insight in the pathophysiology and time course of catabolism, anabolic resistance, and metabolic and endocrine derangements interacting with the provision of calories and proteins.Early provision of high protein intake and caloric overfeeding may confer harm. Refeeding syndrome warrants caloric restriction and to identify patients at risk phosphate monitoring is mandatory.Infectious complications of parenteral nutrition are associated with overfeeding. In recent studies enteral nutrition is no longer superior over parenteral nutrition.Previously reported benefits of glutamine, selenium, and fish oil seem to have vanished in recent studies; however, studies on vitamin C, thiamine, and corticosteroid combinations show promising results. SUMMARY: Studies from the last 2 years will have marked impact on future nutritional support strategies and practice guidelines for critical care nutrition as they challenge several old-fashioned concepts.