Mesenteric, coeliac and splanchnic blood flow in humans during exercise

Abstract

In humans subjected to intense exercise, the splanchnic blood flow is reduced to about 40% (Kjòr et al. 1993) or even as low as 20% of the resting value (Rowell, 1973). Such a substantial reduction in blood flow is not associated with symptoms of abdominal hypoperfusion, which contrasts with patients suffering abdominal angina in whom the splanchnic blood flow is reduced to only 84% of rest (0·98 vs. 1·17 l min¢ in a control group; Buchardt Hansen et al. 1977). Therefore, we hypothesized that the exercise-induced reduction in splanchnic blood flow primarily follows a decrease in the hepato-splenic flow, while the mesenteric circulation remains relatively stable. In contrast to our hypothesis, Qamar & Read (1987) noted a 43 % reduction in the superior mesenteric artery (SMA) blood flow after treadmill exercise. However, Eriksen & Waaler (1994) reported a maintained SMA flow after fasting and postprandial short-duration (4 min) cycling, corroborating observations during submaximal exercise in the dog (Herrick et al. 1940;Van Citters & Franklin, 1969;Vatner, 1975). To evaluate these contradictory results, we assessed splanchnic blood flow (SBF) during fasting and postprandial exercise in healthy volunteers by both Indocyanine Green dye-elimination (dye-elimination) and duplex ultrasound techniques, which permitted separation of the hepato-splenic from the mesenteric circulations. METHODSNineteen healthy non-medicated and non-smoking volunteers aged 28 years (range, 24-35 years), 1·82 m (1·73-1·91 m) tall and weighing 81 kg (57-85 kg) participated in the study after informed consent and approval by the Ethics Committee for Medical Research in Copenhagen (Reg. no. KA 91192). The first ten subjects underwent fasting duplex ultrasound examination of the SMA and 1. Exercise reduces splanchnic blood flow, but the mesenteric contribution to this response is uncertain. 2. In nineteen humans, superior mesenteric and coeliac artery flows were determined by duplex ultrasonography during fasting and postprandial submaximal cycling and compared with the splanchnic blood flow as assessed by the Indocyanine Green dye-elimination technique. 3. Cycling increased arterial pressure, heart rate and cardiac output, while it reduced total vascular resistance. These responses were not altered in the postprandial state. During fasting, cycling increased mesenteric, coeliac and splanchnic resistances by 76, 165 and 126%, respectively, and it reduced corresponding blood flows by 32, 50 and 43% (by 0·18 ± 0·04, 0·42 ± 0·03 and 0·60 ± 0·04 l min¢). Postprandially, mesenteric and splanchnic vascular resistances decreased, thereby elevating regional blood flow, while the coeliac circulation was not influenced. Postprandial cycling did not influence the mesenteric resistance significantly, but its blood flow decreased by 22% (0·46 ± 0·28 l min¢). Coeliac and splanchnic resistance increased by 150 and 63%, respectively, and the corresponding regional blood flow decreased by 51 and 31% (0·49 ± 0·07 and 0·96 ± 0·28 l min¢). Splanchnic blood flow va...

Cerebral herniation in patients with acute E liver failure is correlated with arterial ammonia concentration

“…Group E patients were catheterized as part of another study. 19 In Group A, 20 of 22 patients were mechanically ventilated. In Group B, mechanical ventilation was instituted when HE grade III developed, and the study was performed within 24 hours thereafter.…”

Hypnotic Hallucination of Body Heating Modifies Splanchnic Circulation: Haemodynamic and Ultrasonographic Pilot Study in Normal Volunteers

“…The paradigm of hypnotic body heating therefore reminds that of hyperthyroidism, where vasodilation occurring both in splanchnic and systemic districts is characterized by an increase of circulating blood mass and of flow velocity secondary to opening of arterial-venous shunts (Fazio, Palmieri, Lombardi & Biondi, 2004;Perko, Perko, Just, Secher, & Schroeder, 1996). On the contrary, it is opposite to that of physical exercise, where cardiac output increases while splanchnic flow tends to decrease due to diversion of blood from the abdomen to muscular and subcutaneous tissues (Casiglia et al, 1994(Casiglia et al, , 1997bPerko, Nielsen, & Skak, 1998;Tikhonoff et al, 1999).…”

Effects of Walking for Health Promotion on Oxygen Consumption in Nonexercising Muscle

“…Another reason is that V · O 2pul was kept at a constant level because energy metabolism in sites other than skeletal muscles during exercise may be decreased. For example, it is well known that blood flow in viscera is decreased during exercise (Perko et al, 1998;Osada et al, 1999); thus, along with such decrease, the energy metabolism in viscera may be decreased during the present walking exercise.…”