Cullen J J, Doty R C, Ephgrave K S, Hinkhouse M M, Broadhurst K
Surgical Service, Veterans Administration Medical Center, Iowa City, USA.
J Surg Res. 1999 Jan;81(1):81-6. doi: 10.1006/jsre.1998.5452.
Septic patients are often intolerant of enteral feedings due to a combination of motility disturbances and impaired absorptive function. Our laboratory has previously demonstrated that endotoxemia results in rapid intestinal transit and decreased jejunal absorption of water, electrolytes, and glucose. We hypothesized that the changes in jejunal transit and absorption during endotoxemia may be dependent on the dose of endotoxin.
Under general anesthesia, rats underwent placement of an internal jugular line, a femoral arterial line, and a 20-cm jejunal Thiry-Vella loop. The jejunal segment was perfused with an isotonic solution containing polyethylene glycol. For 90 min, baseline measurements of blood pressure, heart rate, jejunal absorption of water, electrolytes, and glucose, and jejunal transit were made. Following this baseline period I, rats were given 0.9% NaCl (1 ml/kg) or one of three doses of Escherichia coli lipopolysaccharide (0.5, 1.0, or 5.0 mg/kg). Studies were then repeated for an additional 90 min.
Changes in blood pressure and heart rate were similar among the four groups of animals. Endotoxin decreased water and glucose flux, increased potassium flux, and quickened intestinal transit in a dose-dependent fashion.
We conclude that endotoxemia causes dose-dependent changes in jejunal transit and absorption. The effects of increasing doses of endotoxin on jejunal absorptive and motor function do not appear to be mediated by changes in blood pressure or heart rate.
由于动力障碍和吸收功能受损，脓毒症患者通常不耐受肠内喂养。我们实验室先前已证明，内毒素血症会导致肠道快速转运，并降低空肠对水、电解质和葡萄糖的吸收。我们推测，内毒素血症期间空肠转运和吸收的变化可能取决于内毒素的剂量。
在全身麻醉下，给大鼠置入颈内静脉导管、股动脉导管和一个20厘米长的空肠Thiry-Vella袢。用含有聚乙二醇的等渗溶液灌注空肠段。在90分钟内，对血压、心率、空肠对水、电解质和葡萄糖的吸收以及空肠转运进行基线测量。在这个基线期I之后，给大鼠注射0.9%氯化钠（1毫升/千克）或三种剂量的大肠杆菌脂多糖之一（0.5、1.0或5.0毫克/千克）。然后再重复研究90分钟。
四组动物的血压和心率变化相似。内毒素以剂量依赖的方式降低水和葡萄糖通量，增加钾通量，并加快肠道转运。
我们得出结论，内毒素血症会导致空肠转运和吸收出现剂量依赖性变化。内毒素剂量增加对空肠吸收和运动功能的影响似乎不是由血压或心率变化介导的。
