Relevance of non-nutritional calories in mechanically ventilated critically ill patients

Abstract

Background/Objectives:Overfeeding in critically ill patients is associated with many complications. Propofol, dextrose infusion and citrate dialysis provide non-nutritional calories (NNCs), potentially causing overfeeding. The relevance of NNCs for total caloric intake has not been systematically studied.Subjects/Methods:We retrospectively studied adult mechanically ventilated intensive care unit (ICU) patients receiving enteral nutrition with or without supplemental parenteral nutrition. Primary outcome was the proportion of NNCs (from dextrose, propofol and trisodium citrate) to the total energy intake during the first 7 days after ICU admission. In addition, NNC intake groups were compared.Results:In total, we identified 146 patients: 142 patients with NNC median value of 580 kcal (interquartile range 310–1043 kcal) over 7 days and 4 patients without NNC intake. The mean proportion of NNCs was larger during the first days after ICU admission (30.7–36.1%), because of the start-up phase of the nutrition. In the ‘propofol' group and the ‘dextrose' group this proportion levelled off at 6% on day 4. A more stable proportion of 18% was found during the first 7 days of ICU admission in the ‘citrate' group.Conclusions:The mean proportion of NNCs in patients who receive dextrose and/or propofol is low (6%); however, in individual patients it may comprise one-third of the total daily calories. Patients receiving trisodium citrate have higher mean non-nutritional intakes (18%). As NNC intake can be marked in individual patients, close monitoring is warranted when administering high-dose propofol or trisodium citrate anticoagulation to prevent overfeeding.

Continuous renal replacement therapy: a potential source of calories in the critically ill,

“…In fact, there is a role for underfeeding selected patients with obesity and diabetes because this approach results in less hyperglycemia (15,27). Nonnutritional sources of energy such as dextrosecontaining fluids used to treat hypernatremia or administered with intravenous medications, propofol, and the dialysis modalities used in the critically ill have received relatively little attention as sources of energy (28,29). Our CRRT patients were not overfed because most of them were not receiving nutrition support.…”

Does Propofol Sedation Contribute to Overall Energy Provision in Mechanically Ventilated Critically Ill Adults? A Retrospective Observational Study

“…The most frequent reason for ICU admission was major trauma (n = 162, 43.8%). The median [IQR] APACHE II score was 19 [15][16][17][18][19][20][21][22][23][24], 80% required inotropes or vasopressors at some point during their ICU stay, and 65 (17.6%) did not survive to hospital discharge.…”

“…This agrees with 2 previous smaller studies that found the mean amount of energy provided as propofol during the first 7 days of ICU admission was 26-81 kcal/d, representing 6%-9.5% of total energy requirements. 15,16 However significant variation was noted, with some patients receiving a much larger proportion of their daily energy intake as propofol, often in the first few days of admission. Some have suggested that ignoring the energy provided by propofol may lead to overfeeding in critically ill adults.…”

“…Some have suggested that ignoring the energy provided by propofol may lead to overfeeding in critically ill adults. 15,16 In an attempt to compensate for energy provided by propofol, EN or PN volumes may be reduced. However this could result in inadequate delivery of protein, 17 particularly as underfeeding is already prevalent in this patient population; average energy delivery in ICUs internationally is reported to be 61%, 3,4 and average protein delivery is approximately 56% or 0.6 g/kg/d.…”

“…6 In our study, propofol did contribute a moderate proportion of energy in the first 48 hours, before reaching a stable level by day 3, an observation that is consistent with prior work. 15,16 Of note, most patients still failed to receive "adequate" nutrition during the first 48 hours in the ICU, with the greatest deficiency observed in those who did not receive propofol.…”