INTRODUCTIONIn the community, approximately 50% of patients with type 1 or 2 diabetes mellitus (DM) have gastroparesis [1] . Although gastric emptying of either a solid or semi-solid meal is consistently slow in these patients, gastric emptying of liquid meals is variable [1][2][3][4] . The aetiology of slow gastric emptying and the variable rate of liquid emptying are unclear, but may be related to hyperglycemia or autonomic neuropathy [1,[5][6][7] , factors that result in motor dysfunction of both the proximal and distal stomach [1,7,8] . Delayed gastric emptying is also common in critically ill patients [9][10][11] and is associated with disturbed motility of both the proximal and distal stomach [10,12,13] . In health, the proximal stomach is a major determinant of liquid gastric emptying and is regulated by feedback from the small intestine. In health, the fundus relaxes in response to the presence of nutrient in the duodenum [14] . Critically ill patients without DM have been reported to have impaired proximal gastric relaxation, reduced fundic wave activity and a failed recovery of proximal gastric volume to prestimulation level [12] . Currently, there are no data on the impact of DM on gastric motor function or emptying during critical illness, despite the fact that one-third of patients admitted to critical care units have DM [15] . Given that both DM and critical illness are risk factors for disturbed gastric motility, we hypothesized that critically ill patients with DM would have abnormal proximal gastric motor activity during fasting and in response to duodenal nutrient infusion, compared to non-diabetic critically ill patients and healthy humans. Abstract AIM: To investigate the proximal gastric motor response to duodenal nutrients in critically ill patients with longstanding type 2 diabetes mellitus.
MATERIALS AND METHODS
Subjects
METHODS:Proximal gastric motility was assessed (using a barostat) in 10 critically ill patients with type 2 diabetes mellitus (59 ± 3 years) during two 60-min duodenal infusions of Ensure (1 and 2 kcal/min), in random order, separated by 2 h fasting. Data were compared with 15 non-diabetic critically ill patients (48 ± 5 years) and 10 healthy volunteers (28 ± 3 years).
RESULTS:Baseline proximal gastric volumes were similar between the three groups. In diabetic patients, proximal gastric relaxation during 1 kcal/min nutrient infusion was similar to non-diabetic patients and healthy controls. In contrast, relaxation during 2 kcal/ min infusion was initially reduced in diabetic patients (P < 0.05) but increased to a level similar to healthy humans, unlike non-diabetic patients where relaxation was impaired throughout the infusion. Duodenal nutrient stimulation reduced the fundic wave frequency in a dose-dependent fashion in both the critically ill diabetic patients and healthy subjects, but not in critically ill patients without diabetes. Fundic wave frequency in diabetic patients and healthy subjects was greater than in non-diabetic patients.
CONCLUSION:In patients with d...