Effects of norepinephrine and phenylephrine on intestinal oyxgen supply and mucosal tissue oxygen tension

Abstract

Despite major differences in systemic hemodynamics jejunal tissue oxygen supply is not affected by progressively increasing intravenous infusion of norepinephrine and phenylephrine.

The adrenergic coin: perfusion and metabolism

“…First, the authors confirm the well known effect of epinephrine (in contrast to norepinehrine) of increasing glucose and lactate levels in animal models [10,11,12,13] as well as in humans [14,15,16] in controls. The endotoxin challenge in the present model was associated with decreased mean arterial pressure and systemic blood flow.…”

Jejunal tissue oxygenation and microvascular flow motion during hemorrhage and resuscitation

“…In previous studies, we and others have hypothesized that measurements of HBjO 2 are limited to the mucosal and probably submucosal layer of the intestinal wall (8,13,27). However, in a recent investigation, we were able to demonstrate that the light emitted by the eluminating microlightguide penetrates the whole intestinal wall and is reflected by a mirror intermittently placed under the preparation resulting in an increase in light intensity detected by the photomultiplier tube (25). Therefore, measurements of HBjO 2 involve the microvasculature of total intestinal wall.…”

Mechanisms of inducible nitric oxide synthase (iNOS) inhibition-related improvement of gut mucosal acidosis during hyperdynamic porcine endotoxemia

“…The tissue depth depicted by this probe is 130-250 µm. Placing a mir- ror under an excised part of the ileum [10] did not alter the intensity of the back-scattered light and thus confirmed that the catchment volume of the probe was limited to the mucosal and submucosal layers. Ten randomly chosen locations were analyzed every 2 s for 1 min.…”

“…mucosa and submucosa, of the light emitted by the O 2 C® device: the porcine bowel mucosa measures about 350 µm [15] given the average villous height and crypt depth of about 250 µm and 150 µm, respectively. We also excluded a light penetration into the serosal layer, since placing a mirror onto the serosa did not modify the intensity of the LDF or the µHbO 2 signals [10]. Thus, given the unchanged parameters of the mucosal microcirculation, the reduced PCO 2 gap was probably either caused by improved gut wall cellular energy metabolism and/or a redistribution of the mucosal blood flow to the submucosal, muscular and serosal layers.…”