Gastroenterology
-
Comparative Study
Measurement of gastric emptying rate in humans by real-time ultrasound.
Simultaneous studies of gastric emptying by ultrasound and scintigraphy were performed in 14 subjects to assess the use of ultrasound for the measurement of gastric emptying rate. The presence of air in the stomach prevented the acquisition of gastric emptying data by ultrasound in 3 of the 14 subjects. ⋯ A significant correlation between the t1/2 of gastric emptying derived by scintigraphy (anterior scanning and geometric mean of counts obtained by anterior and posterior scanning) and the t1/2 measured by ultrasound was obtained (r2 = 0.7, 0.69, respectively). These results imply that ultrasound can be used for the valid assessment of the gastric emptying rate in humans.
-
Comparative Study
Measurement of gastric emptying time by real-time ultrasonography.
This paper describes an ultrasound method of assessing gastric emptying time based on measurements of the gastric antrum, which is visible in almost all subjects before and after meals. A total of 54 subjects were examined including 18 normal subjects and 36 subjects with idiopathic functional dyspepsia. The emptying time was determined in all subjects by measuring the changes in the cross-sectional area of the gastric antrum. ⋯ A significantly higher degree of dilatation of the gastric antrum was found in dyspeptic patients than in control subjects. Barium x-ray of the stomach in 19 subjects always confirmed the ultrasound finding on the presence or absence of contents within the stomach. We conclude that this kind of ultrasound study of the antropyloric region allows accurate determination of total gastric emptying time.
-
Elevated plasma ammonia level in hepatic cirrhosis has been attributed to a lack of conversion of enteric ammonia into urea or to its entry into systemic circulation via portasystemic shunting, or to both. It is exaggerated by excessive protein intake. Because hyperglucagonemia is well documented in cirrhosis and a protein meal is an effective glucagon secretagogue, plasma glucose, insulin, glucagon, and ammonia levels were determined in 50 cirrhotic patients after an overnight fast. ⋯ Finally, direct effects of glucagon administration on plasma glucose and serum ammonia were examined in 15 cirrhotic patients. Glucose response was significantly blunted in cirrhotic patients as compared with normal subjects, whereas serum ammonia rose promptly but only in cirrhotics, with maximum rise being noted in cirrhotic patients with advanced liver dysfunction. This study, therefore, suggests that hyperglucagonemia may contribute significantly to hyperammonemia in hepatic cirrhosis.
-
Coordination of gallbladder and sphincter of Oddi and effect of cholecystectomy on biliary pressure physiology were investigated in 7 patients using an indwelling microtransducer catheter placed in the bile duct by duodenoscopy. Intramuscular morphine (0.2 mg/kg) to induce a sphincter of Oddi spasm produced no change before cholecystectomy but intravenous caerulein (0.1 microgram/kg) induced pressure elevation coincident with gallbladder contraction on echogram. ⋯ These results show (a) the sphincter of Oddi relaxes when the gallbladder contracts in response to caerulein and (b) the gallbladder acts as a pressure reservoir against the sphincter of Oddi spasm caused by morphine. The latter implies that the spasm of the sphincter of Oddi readily leads to a pressure rise if the gallbladder is absent, which may partly explain a development of postcholecystectomy syndrome.