SUMMARY AND RECOMMENDATIONS
●Nutrition support refers to the enteral or parenteral provision of calories, protein, electrolytes, vitamins, minerals, and fluids.
●Critically ill patients are selected for nutrition support on the basis of whether they have contraindications to enteral nutrition, as well as whether the patient is adequately nourished or malnourished:
•For critically ill surgical patients without contraindications to enteral nutrition, we recommend early (eg, within 48 hours) enteral nutrition (Grade 1B). For critically ill medical patients without contraindications to enteral nutrition, we suggest early enteral nutrition (Grade 2C).
•For critically ill patients who are hemodynamically unstable and have not had their intravascular volume fully resuscitated early enteral nutrition is contraindicated (Grade 2C).
•For adequately nourished patients who have contraindications to enteral nutrition, we recommend NOT initiating early parenteral nutrition (Grade 1A). While the optimal time for starting parenteral nutrition in these patients is unknown, we typically do not start parenteral feeding before one to two weeks have elapsed.
•For malnourished patients who have contraindications to enteral nutrition that are expected to persist one week or less, we suggest NOT initiating parenteral nutrition (Grade 2C). For malnourished patients who have contraindications to enteral nutrition that are expected to persist greater than one week, we suggest parenteral nutrition (Grade 2C).
•For obese patients (BMI ≥30 kg/m2), the optimal approach to nutrition is unknown. We prefer that enteral and parenteral nutrition and choice of nutrition in this population be the same as for the adequately nourished critically ill patient.
●An acceptable initial nutritional goal is 8 to 10 kcal of calories/kg per day and then 18 to 25 kcal and 1.5 grams of protein/kg per day after five to seven days, although these targets have not been rigorously validated.