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- Gunnarsson, Ulf, 1967-, et al.
(författare)
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Centrally mediated influences of hypertonic NaCl and angiotensin II on regional blood flow and hemodynamic responses to hypotensive hemorrhage in conscious sheep.
- 1994
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Ingår i: Shock. - 1073-2322 .- 1540-0514. ; 2:1, s. 60-7
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Tidskriftsartikel (refereegranskat)abstract
- The influence of separate and combined intracerebroventricular (ICV) infusions of hypertonic (.5 M) NaCl (HTNa) at .02 mL min-1 and angiotensin II (ANG II) at 1 pmol kg-1 min-1 on tolerance to hemorrhage, accompanying systemic hemodynamic changes, and regional blood flow was studied in adult conscious sheep. Corresponding measurements during ICV .9% NaCl served as controls. The hemorrhage volume needed to lower the blood pressure to about 50 mmHg was significantly larger during treatment with HTNa and HTNa/ANG II (27.8 +/- 2.2 and 28.3 +/- 2.5 mL kg-1, respectively; p < .001; about 45% of estimated blood volume) as well as during ANG II (20.1 +/- 1.3 mL kg-1; p < .01) compared to controls (15.1 +/- .7 mL kg-1; about 25% of estimated blood volume). In spite of a larger hemorrhage volume, the lowering of the cardiac output was not accentuated, and its subsequent recovery was not impaired during ICV infusion of HTNa or HTNa/ANG II. Similarly, the posthemorrhage restoration of the systemic blood pressure was not negatively affected by the more pronounced hypovolemia induced during the ICV treatments compared to controls. In contrast to ANG II, HTNa infusion, alone or in combination with ANG II, was accompanied by a significantly lower renal blood flow, and a higher renovascular resistance, during the posthemorrhage period. The femoral blood flow was maintained or even slightly elevated after hemorrhage in all experiments. The integrated results of the study imply differentiated hemodynamic effects of centrally administered HTNa and ANG II.(ABSTRACT TRUNCATED AT 250 WORDS)
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| 2. |
- Rasmussen, I, et al.
(författare)
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Detection of liver ischemia using microdialysis during experimental peritonitis in pigs.
- 1994
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Ingår i: Shock. - : Ovid Technologies (Wolters Kluwer Health). - 1073-2322 .- 1540-0514. ; 1:1, s. 60-6
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Tidskriftsartikel (refereegranskat)abstract
- The liver oxygen delivery (DO2) and consumption (VO2) were measured in a porcine model of septic shock induced by fecal peritonitis. Lactate and hypoxanthine were simultaneously monitored in hepatic extracellular fluid and in central venous blood using a microdialysis technique. Animals were divided into a control group (n = 6) and a peritonitis group (n = 6). Peritonitis was induced by installation of a standardized amount of autologous feces into the abdominal cavity. The animals were followed for 5 h. The changes in the liver during peritonitis were, a decreased DO2, a increased, maintained, or decreased VO2, an increased oxygen extraction, and a loss of net hepatic lactate uptake. Parallel to these changes, systemic lactic acidosis developed. Intrahepatic lactate and hypoxanthine increased during peritonitis reflecting liver ischemia. The increase of these metabolites was seen concomitantly in the liver and in central venous blood. There was a wide variability of the individual response to the septic challenge among the animals. The limited hepatic oxygen delivery, and the increased needs for oxygen led to flow-dependent oxygen consumption, and signs of liver ischemia in severe sepsis. Intrahepatic and intravenous microdialysis may be useful for monitoring of the individual time course of hepatic and systemic ischemia in sepsis.
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