Effects of Standard vs Energy‐Dense Formulae on Gastric Retention, Energy Delivery, and Glycemia in Critically Ill Patients

Abstract

Background: Energy-dense formulae are often provided to critically ill patients with enteral feed intolerance with the aim of increasing energy delivery, yet the effect on gastric emptying is unknown. The rate of gastric emptying of a standard compared with an energy-dense formula was quantified in critically ill patients. Methods: Mechanically ventilated adults were randomized to receive radiolabeled intragastric infusions of 200 mL standard (1 kcal/mL) or 100 mL energy-dense (2 kcal/mL) enteral formulae on consecutive days in this noninferiority, blinded, crossover trial. The primary outcome was scintigraphic measurement of gastric retention (percentage at 120 minutes). Other measures included area under the curve (AUC) for gastric retention and intestinal energy delivery (calculated from gastric retention of formulae over time), blood glucose (peak and AUC), and intestinal glucose absorption (using 3-O-methyl-D-gluco-pyranose [3-OMG] concentrations). Comparisons were undertaken using paired mixedeffects models. Data presented are mean ± SE. Results: Eighteen patients were studied (male/female, 14:4; age, 55.2 ± 5.3 years). Gastric retention at 120 minutes was greater with the energy-dense formula (standard, 17.0 ± 5.9 vs energy-dense, 32.5 ± 7.1; difference, 12.7% [90% confidence interval, 0.8%-30.1%]). Energy delivery (AUC 120 , 13,038 ± 1119 vs 9763 ± 1346 kcal/120 minutes; P = 0.057), glucose control (peak glucose, 10.1 ± 0.3 vs 9.7 ± 0.3 mmol/L, P = 0.362; and glucose AUC 120 8.7 ± 0.3 vs 8.5 ± 0.3 mmol/L.120 minutes, P = 0.661), and absorption (3-OMG AUC 120 , 38.5 ± 4.0 vs 35.7 ± 4.0 mmol/L.120 minutes; P = .508) were not improved with the energy-dense formula. Conclusion: In critical illness, administration of an energy-dense formula does not reduce gastric retention, increase energy delivery to the small intestine, or improve glucose absorption or glucose control; instead, there is a signal for delayed gastric emptying.

Modified low ratio ketogenic therapy in the treatment of adults with super‐refractory status epilepticus

“…The use of ketogenic therapy in the critical care setting also poses a practical challenge because of unavoidable or incidental carbohydrate administration, enteral feeding intolerance, hypoglycemia, and metabolic acidosis 19 . Additionally, increasing the fat content of enteral nutrition may further slow gastric emptying, worsen enteral feed intolerance, and reduce nutrient absorption 20 …”

“…19 Additionally, increasing the fat content of enteral nutrition may further slow gastric emptying, worsen enteral feed intolerance, and reduce nutrient absorption. 20 Given that ketogenic therapy is a potential therapeutic intervention for SRSE, yet it may be poorly tolerated in adult patients who are critically ill, and its use in this cohort has been rarely reported, we conducted a retrospective cohort study at two large volume quaternary hospital ICUs to explore tolerability of ketogenic therapy and adverse events associated with its use.…”

Comparative effects of low‐carbohydrate, full‐strength and low‐alcohol beer on gastric emptying, alcohol absorption, glycaemia and insulinaemia in health

“…They then consumed 600 mL of either (i) full‐strength beer (5.0% w/v alcohol, 246 kcal, 19.2 g carbohydrate); (ii) low‐carbohydrate beer (4.6% w/v alcohol, 180 kcal, 5.4 g carbohydrate); or (iii) low‐alcohol beer (2.6% w/v alcohol, 162 kcal, 17.4 g carbohydrate) (Hahn Brewing Company, Sydney, NSW, Australia) each radiolabelled with 20 MBq 99m Tc‐calcium phytate (Radpharm Scientific, Belconnen, ACT, Australia), within 10 minutes. 99m Tc‐calcium phytate is a colloid that has been used widely as a marker of liquid gastric emptying 18–20 . Another colloid ( 99m Tc‐sulfur colloid) was tested to determine the stability of the radiolabel in the presence of acetic acid (to mimic the gastric environment) with and without alcohol.…”

“…99m Tc-calcium phytate is a colloid that has been used widely as a marker of liquid gastric emptying. [18][19][20] Another colloid ( 99m Tc-sulfur colloid) was tested to determine the stability of the radiolabel in the presence of acetic acid (to mimic the gastric environment) with and without alcohol. In vitro experiments utilising instant thin layer chromatography (ITLC) demonstrated at least 98% labelling over a 3 hour period, indicative of little, or no, degradation over time (data not shown).…”

Protein metabolism in critical illness

“…Improving protein digestibility by providing dietary protein as free amino acids or oligo peptides that do not require digestion increases amino acid availability in the circulation for peripheral tissues in health [40]. This could be a potential strategy in critically ill patients where protein is delivered into the stomach and delayed gastric emptying may compromise the systemic release of dietary amino acids [41].…”