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Plasma Volume Expansion (plasma + volume_expansion)
Selected AbstractsAcute Hypervolaemia Improves Arterial Oxygen Pressure in Athletes with Exercise-Induced HypoxaemiaEXPERIMENTAL PHYSIOLOGY, Issue 4 2003Gerald S. Zavorsky The aim of this study was to determine the effect of acute plasma volume expansion on arterial blood-gas status during 6.5 min strenuous cycling exercise comparing six athletes with and six athletes without exercise-induced arterial hypoxaemia (EIAH). We hypothesized that plasma volume expansion could improve arterial oxygen pressure in a homogeneous sample of athletes - those with EIAH. In this paper we have extended the analysis and results of our recently published surprising findings that lengthening cardiopulmonary transit time did not improve arterial blood-gas status in a heterogeneous sample of endurance cyclists. One 500 ml bag of 10% Pentastarch (infusion condition) or 60 ml 0.9% saline (placebo) was infused prior to exercise in a randomized, double-blind fashion on two different days. Power output, cardiac output, oxygen consumption and arterial blood gases were measured during strenuous exercise. Cardiac output and oxygen consumption were not affected by acute hypervolaemia. There were group × condition interaction effects for arterial oxygen pressure and alveolar-arterial oxygen pressure difference, suggesting that those with hypoxaemia experienced improved arterial oxygen pressure (+4 mmHg) and lower alveolar-arterial oxygen pressure difference (-2 mmHg) with infusion. In conclusion, acute hypervolaemia improves blood-gas status in athletes with EIAH. The impairment of gas exchange occurs within the first minute of exercise, and is not impaired further throughout the remaining duration of exercise. This suggests that arterial oxygen pressure is only minimally mediated by cardiac output. [source] Haemodilution induced by hydroxyethyl starches 130/0.4 is similar in septic and non-septic patientsACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 2 2008P. MEYER Background: Fluid therapy induces haemodilution related to plasma volume expansion. The aim of our study was to compare haemodilution after a single hydroxyethyl starches (HES) 130/0.4 infusion in two groups of patients, one with and one without sepsis. We hypothesized that a single HES challenge would induce similar sustained haemodilution in both groups. Methods: In this prospective preliminary study, patients predicted to require a single further volume-expander infusion were included immediately before receiving 500 ml of 6% HES 130/0.4 over a 15-min period. No additional fluid was administered over the next 8 h. Haematocrit, and serum albumin and protein were determined immediately before HES infusion then after 1, 2, 3, 4, and 8 h. Results: Twelve patients were included in each group. In both groups, all three haemodilution markers had significantly lower values after 1 h than at baseline. None of the values after 1 and 3 h differed significantly between the two groups. Neither did any of the other study variables show significant differences between the groups with and without sepsis. Conclusion: We found that a starch-based compound was as effective in inducing haemodilution in patients with sepsis as in controls without sepsis, suggesting that HES may remain within the intravascular space even in patients with sepsis. Haemodilution parameters such as haematocrit, serum albumin and serum protein are useful for assessing the duration of plasma volume expansion induced by fluid therapy in critically ill patients. [source] Comparison of Two Oral Electrolyte Solutions and Route of Administration on the Abomasal Emptying Rate of Holstein-Friesian CalvesJOURNAL OF VETERINARY INTERNAL MEDICINE, Issue 3 2006Mohammad Nouri Dehydrated calves with diarrhea are routinely given an oral electrolyte solution (OES) by suckling or esophageal intubation. An important issue related to rehydration therapy is the rate of OES delivery to the small intestine. It is widely assumed that the glucose content of the OES does not impact the speed of resuscitation and that fluid administered by esophageal intubation provides a similar resuscitative response to that obtained by suckling. The aims of this study were to compare the abomasal emptying rate in calves suckling an OES containing a high or low glucose concentration and in calves administered a high-glucose OES by suckling or esophageal intubation. Seven male Holstein-Friesian calves were given the following treatments in random order: 2 L of a commercially available high-glucose OES ([glucose] = 405 mM) by suckling or esophageal intubation or 2 L of a commercially available low-glucose OES ([glucose] = 56 mM) by suckling. Abomasal emptying rate was determined by acetaminophen absorption, ultrasonography, and glucose absorption. High-glucose OES rapidly increased plasma glucose concentration after suckling but produced a slower rate of abomasal emptying than did low-glucose OES. Esophageal intubation of high-glucose OES produced the same initial change in abomasal volume as did suckling, but delayed the rate of OES delivery to the small intestine. Our results suggest that suckling a low-glucose OES provides the fastest rate of abomasal emptying and plasma volume expansion, whereas a high-glucose OES provides the most appropriate oral solution for treating hypoglycemic calves. [source] Immune effect of hypertonic saline: fact or fiction?ACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 6 2004J. A. Křlsen-Petersen Hypertonicity affects many parts of the immune system. Animal studies and experiments in isolated cell cultures show that hypertonicity reversibly suppresses several neutrophil functions and at the same time up-regulates T-lymphocyte function. Infusion of hypertonic saline with or without colloids may thus, besides providing efficient plasma volume expansion, ameliorate the detrimental consequences on the immune function of trauma, shock, reperfusion, and major surgery. However, the few clinical studies conducted to date, specifically addressing the immune effect of hypertonic saline infusion, have shown little, if any, effect on markers of immune function, and larger clinical trials have not demonstrated benefit in terms of morbidity or mortality. Thus, as opposed to animal and cell-culture studies, the immune-modulating properties of hypertonic saline infusion would appear to be of limited value in clinical practice. This review presents in vitro studies, animal experiments, and clinical trials which investigated the consequences of hypertonic saline on markers of immune function. [source] Modulation of body fluids and angiotensin II receptors in a rat model of intra-uterine growth restrictionTHE JOURNAL OF PHYSIOLOGY, Issue 3 2005Sophie Bédard We previously reported that sodium restriction during pregnancy reduces plasma volume expansion and promotes intra-uterine growth restriction (IUGR) in rats while it activates the renin,angiotensin,aldosterone system (RAAS). In the present study, we proceeded to determine whether expression of the two angiotensin II (ANGII) receptor subtypes (AT1 and AT2) change in relation to maternal water,electrolyte homeostasis and fetal growth. To this end, pregnant (gestation day 15) and non-pregnant Sprague-Dawley rats were randomly assigned to two groups fed either normal, or Na+ -restricted diets for 7 days. At the end of the treatment period, plasma aldosterone and renin activity as well as plasma and urine electrolytes were measured. Determinations for AT1 and AT2 mRNA and protein were made by RNase protection assay and photoaffinity labelling, respectively, using a number of tissues implicated in volume regulation and fetal growth. In non-pregnant rats, Na+ restriction decreases Na+ excretion without altering plasma volume, plasma Na+ concentration or the expression of AT1 and AT2 mRNA or protein in the tissues examined. In normally fed pregnant rats when compared to non-pregnant controls, AT1 mRNA increases in the hypothalamus as well as pituitary and declines in uterine arteries, while AT1 protein decreases in the kidney and AT2 mRNA declines in the adrenal cortex. In pregnant rats, Na+ restriction induces a decrease in plasma Na+, an increase in plasma urea, as well as a decline in renal urea and creatinine clearance rates. Protein levels for both AT1 and AT2 in the pituitary and AT2 mRNA in the adrenal cortex are lower in the Na+ -restricted pregnant group when compared to normally fed pregnant animals. Na+ restriction also induces a decrease in AT1 protein in the placenta. In conclusion, these results suggest that pregnancy may increase sensitivity to Na+ depletion by the tissue-specific modulation of ANGII receptors. Finally, these receptors may be implicated in the IUGR response to low Na+. [source] One-year infant outcome in women with early-onset hypertensive disorders of pregnancyBJOG : AN INTERNATIONAL JOURNAL OF OBSTETRICS & GYNAECOLOGY, Issue 2 2008A Rep Objectives, To evaluate the role of plasma volume expansion on 1-year infant outcome after severe hypertensive disorders of pregnancy and to determine prognostic factors for adverse neurodevelopmental infant outcome. Design, Randomised controlled trial, observational prognostic study. Setting, Two university hospitals in Amsterdam, The Netherlands. Population, One hundred and seventy-two infants alive of 216 mothers with severe hypertensive disorders of pregnancy who were randomised for a temporising management strategy with or without plasma volume expansion. Methods, At 1 year of corrected age, a neurological examination according to Bayley (mental development index [MDI] and psychomotor development index [PDI]) and Touwen was performed. Main outcome measures, Adverse neurodevelopmental infant outcome was defined as a MDI/PDI score below 70 and/or an abnormal Touwen. Risk factors for adverse neurodevelopmental outcome were explored by univariate and multivariate analyses. Results, Adverse neurodevelopmental infant outcome was observed in 31 infants (18%). There were no differences between the randomisation groups. In multivariate analysis, an association with abnormal umbilical artery/middle cerebral artery Doppler ratio higher than the median, major neonatal morbidity, higher education of the parents, multiparity and Caucasian ethnicity was observed. Conclusion, Nearly 70% of the infants were alive at 1 year without adverse neurodevelopmental outcome. Maternal plasma volume expansion during pregnancy has no effect on 1-year infant outcome. The prediction of adverse outcome at 1 year by perinatal parameters is limited. [source] An antidiabetic thiazolidinedione induces eccentric cardiac hypertrophy by cardiac volume overload in ratsCLINICAL AND EXPERIMENTAL PHARMACOLOGY AND PHYSIOLOGY, Issue 1-2 2004Kenji Arakawa Summary 1.,To assess the involvement of volume overload in the development of cardiac hypertrophy during treatment with an antidiabetic thiazolidinedione, changes in cardiac anatomy and parameters of cardiac volume overload were evaluated in female Sprague-Dawley rats treated with the thiazolidinedione derivative T-174. 2.,Two week administration of T-174 (13 and 114 mg/kg per day) increased absolute and relative heart weights by 11,24%, demonstrating the development of cardiac hypertrophy. There was no evidence of oedema in hearts from treated rats. 3.,Both plasma and blood volumes were increased in T-174-treated rats without any changes in systolic blood pressure and heart rate, whereas haematocrit was decreased. In accordance with the existence of volume overload, both left ventricular end-diastolic pressure and right atrial pressure were increased. Morphometric analysis of hearts revealed that T-174 induced eccentric heart hypertrophy, as characterized by a small increase in wall thickness and a large increase in the chamber volume, which is characteristic of volume overload. Volume overload is suggested as the possible trigger mechanism because blood volume expansion preceded cardiac hypertrophy and there was a high correlation between heart weight and blood volume. 4.,T-174-treated streptozotocin-induced diabetic rats also exhibited blood volume expansion and cardiac hypertrophy. 5.,These findings suggest that cardiac volume overload is induced by plasma volume expansion and contributes to the development of eccentric cardiac hypertrophy during treatment with antidiabetic thiazolidinediones. Although thiazolidinediones are insulin-sensitizing agents, these cardiac effects are likely to be mediated independently of insulin. [source] |