Fluids, Electrolytes, Acid-Base Disorders, and Nutrition Support

Adverse effects of overfeeding – Do not exceed 4–5 mg/kg/minute of glucose/carbohydrate in

exceed 1.3–1.5 x measured REE or 25–30 kcal/kg/day for most patients); do not exceed soybean

oil (SO)-ILE intake of 2.5 g/kg/day; most clinicians limit SO-ILE in critically ill patients to around

1 g/kg/day or less.

Hypercapnia: It was traditionally thought that excessive glucose intake alone was responsible for

hypercapnia observed during overfeeding. However, studies of acutely ill patients showed that

overfeeding (e.g., 1.3 x BEE) (Chest 1992;102:551-5). Because most institutions lack the ability to

measure energy expenditure, estimates are used. If the patient experiences hypercapnia without a

known cause, the nutrition therapy should be suspected and the caloric intake empirically decreased

(especially if the patient is having difficulty weaning from the ventilator).

Hyperglycemia: In a retrospective study of 102 patients receiving PN and who were not predisposed to

hyperglycemia, dextrose intakes in excess of 5 mg/kg/minute resulted in substantial hyperglycemia

Patients with stress-induced hyperglycemia or diabetes are even more susceptible to hyperglycemia

with EN or PN. This is one reason (of many) that critically ill patients who require PN should receive

PN via continuous infusion rather than cyclic infusion (i.e., over 12–14 hour/night), even if they

tolerated a cyclic infusion of PN prior to ICU admission (Nutr Clin Pract 2023;38:1263-72).

Fatty infiltration of the liver: May be because of overfeeding with fat or carbohydrate. Usually

presents as a cholestatic liver disease (increased gamma-glutamyl transferase (GGT), alkaline

phosphatase, and ultimately bilirubin) after at least 1 week to 10 days of overfeeding (Arch Surg

1978;113:504-8). May be transient or reversible or can progress to end-stage liver disease. Throughout

a few weeks, patients can appear jaundiced. Patients with critical illness and/or infections tend to

be more susceptible to hepatic steatosis compared with non–critically ill patients (possibly because

of an exaggerated inflammatory process). Although treatment with fish oil appears promising in

are limited. Usual treatment for adult patients with suspected PN-associated liver disease is first to

ensure that the patient is not being overfed. Although evidence is lacking, most nutrition support

clinicians would agree that if 100% SO-ILE is being used, consideration of an ILE formulation

with a lower percentage of SO is warranted (refer PN formulation section for description of ILE

formulations). Cyclic PN (when PN is infused over fewer hours per day) may be considered for

patients who are no longer critically ill. However, cyclic PN is typically not appropriate for critically

ill patients due to the high glucose infusion rate and large volumes of fluid (relative to time) required

for administration. Reinstituting EN as soon as possible (if possible) is of utmost importance.

Guideline recommendations