technetium-tc-99m-sulfur-colloid and Critical-Illness

It is assumed that delayed gastric emptying (GE) occurs frequently in critical illness; however, the prevalence of slow GE has not previously been assessed using scintigraphy. Furthermore, breath tests could potentially provide a convenient method of quantifying GE, but have not been validated in this setting. The aims of this study were to (i) determine the prevalence of delayed GE in unselected, critically ill patients and (ii) evaluate the relationships between GE as measured by scintigraphy and carbon breath test.. Prospective observational study.. Mixed medical/surgical intensive care unit.. 25 unselected, mechanically ventilated patients (age 66 years (49-72); and 14 healthy subjects (age 62 years (19-84)).. GE was measured using scintigraphy and (14)C-breath test. A test meal of 100 ml Ensure (standard liquid feed) labelled with (14)C octanoic acid and (99m)Technetium sulphur colloid was placed in the stomach via a nasogastric tube.. Gastric 'meal' retention (scintigraphy) at 60, 120, 180 and 240 min, breath test t(50) (BTt(50)), and GE coefficient were determined.. Of the 24 patients with scintigraphic data, GE was delayed at 120 min in 12 (50%). Breath tests correlated well with scintigraphy in both patients and healthy subjects (% retention at 120 min vs BTt(50); r(2)=0.57 healthy; r(2)=0.56 patients; p≤0.002 for both).. GE of liquid nutrient is delayed in approximately 50% of critically ill patients. Breath tests correlate well with scintigraphy and are a valid method of GE measurement in this group.

Topics: Adult; Aged; Aged, 80 and over; Breath Tests; Carbon Dioxide; Carbon Radioisotopes; Critical Illness; Enteral Nutrition; Exhalation; Female; Follow-Up Studies; Gastric Emptying; Gastroparesis; Humans; Intensive Care Units; Male; Middle Aged; Prospective Studies; Radionuclide Imaging; Stomach; Technetium Tc 99m Sulfur Colloid; Young Adult

Delayed gastric emptying occurs frequently in critically ill patients and has the potential to adversely affect both the rate, and extent, of nutrient absorption. However, there is limited information about nutrient absorption in the critically ill, and the relationship between gastric emptying (GE) and absorption has hitherto not been evaluated. The aim of this study was to quantify glucose absorption and the relationships between GE, glucose absorption and glycaemia in critically ill patients.. Studies were performed in nineteen mechanically-ventilated critically ill patients and compared to nineteen healthy subjects. Following 4 hours fasting, 100 ml of Ensure, 2 g 3-O-methyl glucose (3-OMG) and 99mTc sulphur colloid were infused into the stomach over 5 minutes. Glucose absorption (plasma 3-OMG), blood glucose levels and GE (scintigraphy) were measured over four hours. Data are mean +/- SEM. A P-value < 0.05 was considered significant.. Absorption of 3-OMG was markedly reduced in patients (AUC240: 26.2 +/- 18.4 vs. 66.6 +/- 16.8; P < 0.001; peak: 0.17 +/- 0.12 vs. 0.37 +/- 0.098 mMol/l; P < 0.001; time to peak; 151 +/- 84 vs. 89 +/- 33 minutes; P = 0.007); and both the baseline (8.0 +/- 2.1 vs. 5.6 +/- 0.23 mMol/l; P < 0.001) and peak (10.0 +/- 2.2 vs. 7.7 +/- 0.2 mMol/l; P < 0.001) blood glucose levels were higher in patients; compared to healthy subjects. In patients; 3-OMG absorption was directly related to GE (AUC240; r = -0.77 to -0.87; P < 0.001; peak concentrations; r = -0.75 to -0.81; P = 0.001; time to peak; r = 0.89-0.94; P < 0.001); but when GE was normal (percent retention240 < 10%; n = 9) absorption was still impaired. GE was inversely related to baseline blood glucose, such that elevated levels were associated with slower GE (ret 60, 180 and 240 minutes: r > 0.51; P < 0.05).. In critically ill patients; (i) the rate and extent of glucose absorption are markedly reduced; (ii) GE is a major determinant of the rate of absorption, but does not fully account for the extent of impaired absorption; (iii) blood glucose concentration could be one of a number of factors affecting GE.

Topics: Adult; Aged; Blood Glucose; Critical Illness; Dietary Sucrose; Enteral Nutrition; Female; Food, Formulated; Gastric Emptying; Glycemic Index; Guanosine; Humans; Intestinal Absorption; Male; Middle Aged; Technetium Tc 99m Sulfur Colloid