Diuretic responses to Ringer's solution and 20% albumin at different arterial pressures.

Intravenous volume loading is a common treatment when hypovolemia is a potential cause of oliguria. We studied whether the effectiveness of Ringer's solution and 20% albumin in inducing diuresis differs depending on the mean arterial pressure (MAP). For this purpose, volume kinetic analysis was performed based on urine output and hemoglobin-derived plasma dilution obtained during and after 136 infusions of Ringer and 85 infusions of 20% albumin.

Recruitment of efferent lymph during infusion of 20 % albumin.

Background: Intravenous infusion of hyper-oncotic 20 % albumin expands the plasma volume by approximately twice the infused volume. We investigated whether the recruited fluid stems from accelerated flow of efferent lymph, which would add protein to the plasma, or from reversed transcapillary solvent filtration, where the solvent is expected to be low in protein.

Methods: We analyzed data from 27 intravenous infusions of 20 % albumin (3 mL/kg; approximately 200 mL) over 30 min given to 27 volunteers and patients.

Plasma volume expansion reveals hidden metabolic acidosis in patients with diabetic ketoacidosis.

Background: Hyperchloremic metabolic acidosis that develops during the treatment of diabetic ketoacidosis is usually attributed to the chloride content of resuscitation fluids. We explored an alternative explanation, namely that fluid-induced plasma volume expansion alters the absolute differences in the concentrations of sodium and chloride (the Na-Cl gap) enough to affect the acid-base balance. We analyzed data from a prospective single-center cohort study of 14 patients treated for diabetic ketoacidosis.

Plasma disappearance rate of albumin when infused as a 20% solution.

Background: The transcapillary leakage of albumin is increased by inflammation and major surgery, but whether exogenous albumin also disappears faster is unclear.

Methods: An intravenous infusion of 3 mL/kg of 20% albumin was given over 30 min to 70 subjects consisting of 15 healthy volunteers, 15 post-burn patients, 15 patients who underwent surgery with minor bleeding, 10 who underwent surgery with major bleeding (mean, 1.1 L) and 15 postoperative patients.

Serum Creatinine Levels and Nephrocheck® Values With and Without Correction for Urine Dilution-A Multicenter Observational Study.

Background: The Nephrocheck® test is a single-use cartridge designed to measure the concentrations of two novel cell-cycle arrest biomarkers of acute kidney injury, namely tissue inhibitor of metalloproteinase 2 (TIMP-2) and insulin-like growth factor binding protein 7 (IGFBP7). Correlations of serum creatine values and TIMP-2 and IGFBP7 with and without correction for urine dilution have not been previously undertaken in patients undergoing major abdominal surgery. We hypothesized that the Nephrocheck® values would be significantly different with and without correction for urine dilution in patients with elevated creatinine values post major abdominal surgery.

Plasma Volume Expansion and Fluid Kinetics of 20% Albumin During General Anesthesia and Surgery Lasting for More Than 5 Hours.

Background: Intraoperative administration of crystalloid for plasma volume expansion may be reduced by use of hyperoncotic albumin. However, the degree of plasma volume expansion with administration of 20% albumin is poorly quantitated. We estimated the amount of volume expansion attributable to 20% albumin administration in patients undergoing surgery for more than 5 hours.

Can perioperative hemodilution be monitored with non-invasive measurement of blood hemoglobin?

Background: Trends in non-invasive measurements of blood hemoglobin (Hb) may be useful for identifying the need for transfusion in the perioperative period.

Methods: Crystalloid fluid (5-20 mL/kg) was administered intravenously or by mouth to 30 volunteers and 33 surgical patients in five non-randomized clinical studies where Hb was measured on 915 occasions by non-invasive (Radical-7™) and invasive methodology. The hemodilution curves were compared by volume kinetic analysis and linear regression, with the slope and scattering of the data as key outcome measures.

Plasma concentrations of syndecan-1 are dependent on kidney function.

Background: Elevated plasma concentrations of syndecan-1 and heparan sulfate in studies of trauma, sepsis, and major surgery are commonly assumed to indicate acute glycocalyx degradation. We explored a possible role of the kidneys for these elevations.

Methods: Plasma and urine concentrations of syndecan-1, heparan sulfate, and biomarkers of inflammation were measured over 5 hours in 15 hospital patients treated for post-burn injury.

Elevated Plasma Concentrations of Syndecan-1 Do Not Correlate With Increased Capillary Leakage of 20% Albumin.

Background: Preclinical experiments show that an inflammatory reaction causes degradation of the endothelial glycocalyx layer and accelerated capillary leakage of albumin and fluid. The hypothesis in the present study was that elevated plasma concentrations of glycocalyx degradation products are associated with greater capillary leakage in humans.

Methods: This open clinical trial involved administration of an intravenous infusion of 20% albumin at 3 mL/kg over 30 minutes to 15 postburn patients who showed an activated inflammatory response.

Electrolyte-based calculation of fluid shifts after infusing 0.9% saline in severe hyperglycemia.

Background: Early treatment of severe hyperglycemia involves large shifts of body fluids that entail a risk of hemodynamic instability. We studied the feasibility of applying a new electrolyte equation that estimates the degree of volume depletion and the distribution of infused 0.9% saline in this setting.

Kinetics of crystalloid fluid in hyperglycemia; an open-label exploratory clinical trial.

Background: Infusion with 0.9% saline is a mainstay in the treatment of severe hyperglycemia, but the kinetics of the saline volume in this setting has not been studied.

Methods: An intravenous infusion of 1 L of 0.

Plasma volume expansion and capillary leakage of 20% albumin in burned patients and volunteers.

Background: Burn injury is associated with a long-standing inflammatory reaction. The use of albumin solutions for plasma volume support is controversial because of concerns of increased capillary leakage, which could aggravate the commonly seen interstitial oedema.

Methods: In the present open controlled clinical trial, an intravenous infusion of 20% albumin at 3 mL/kg was given over 30 min to 15 burn patients and 15 healthy volunteers.

The Extended Starling principle needs clinical validation.

The Revised (or "Extended") Starling principle is based on highly controlled laboratory-based frog and rodent experiments and remains a hypothesis awaiting clinical validation. A key point is that the endothelial glycocalyx layer moves the oncotic gradient from being between the plasma and the interstitium to between the plasma and a virtually protein-free space between the glycocalyx and the endothelial cell membrane, which dramatically changes the prerequisites for fluid absorption from tissue to plasma. However, many experimental and clinical observations in humans agree poorly with the new microcirculatory proposals.

Kinetics of Ringer's Solution in Extracellular Dehydration and Hemorrhage.

Background: Ringer's solution might be used to treat volume depletion (extracellular dehydration) and hemorrhage, but there is no integrated view of how these fluid balance disorders influence the kinetics of the infused volume.

Methods: Acute dehydration (mean 1.7 L) was induced by repeated doses of furosemide (5 mg) in 10 healthy male volunteers, and 0.

Long Intravascular Persistence of 20% Albumin in Postoperative Patients.

Background: Albumin may persist intravascularly for a shorter time in patients after major surgery than in healthy volunteers due to a surgery-induced breakdown (shedding) of the endothelial glycocalyx layer.

Methods: In this nonrandomized clinical trial, an IV infusion of 3 mL/kg of 20% albumin was given at a constant rate during 30 minutes to 15 patients on the first day after major open abdominal surgery (mean operating time 5.9 h) and to 15 conscious volunteers.

Fluid volume kinetics of 20% albumin.

Aims: A population kinetic model was developed for the body fluid shifts occurring when 20% albumin is given by intravenous infusion. The aim was to study whether its efficacy to expand the plasma volume is impaired after major surgery.

Methods: An intravenous infusion of 3 mL/kg 20% albumin over 30 minutes was given to 15 volunteers and to 15 patients on the 1 day after major open abdominal surgery.

Biomarkers of endothelial injury in plasma are dependent on kidney function.

Background: Injury (shedding) of the endothelial glycocalyx layer, which alters local blood flow and microvascular permeability, is assessed by measuring components of this layer in circulating blood. The influence of renal function on their concentrations is unknown.

Methods: Plasma and urine concentrations of three shedding products (syndecan-1, hyaluronic acid, and heparan sulfate) and creatinine were measured over 5 hours in 15 healthy volunteers and 15 postoperative patients; this guaranteed a spread of kidney functions.

Volume kinetic evaluation of fluid turnover after oral intake of tap water, lemonade and saline in volunteers.

Background: Volume kinetic fluid turnover of three beverages was investigated for the purpose of estimating their rates of absorption and elimination as well as their maximum effect on the blood volume. The results were then used to simulate the effects of ingesting different combinations of these fluids.

Method: Ten healthy volunteers ingested 0.

Fluid distribution kinetics during cardiopulmonary bypass.

Objective: The purpose of this study was to examine the isovolumetric distribution kinetics of crystalloid fluid during cardiopulmonary bypass.

Methods: Ten patients undergoing coronary artery bypass grafting participated in this prospective observational study. The blood hemoglobin and the serum albumin and sodium concentrations were measured repeatedly during the distribution of priming solution (Ringer's acetate 1470 ml and mannitol 15% 200 ml) and initial cardioplegia.

Preoperative urine-specific gravity and the incidence of complications after hip fracture surgery: A prospective, observational study.

Background: Mild to moderately severe dehydration is common in the elderly, but its relationship to surgical outcome is unclear.

Objectives: To study the incidence of dehydration prior to hip fracture surgery and its relationship to postoperative complications.

Design: Prospective observational study.

Interactions between the volume effects of hydroxyethyl starch 130/0.4 and Ringer´s acetate.

Introduction: The turnover of Ringer´s solutions is greatly dependent on the physiological situation, such as the presence of dehydration or anaesthesia. The present study evaluates whether the kinetics is affected by previous infusion of colloid fluid.

Methods: Ten male volunteers with a mean age of 22 years underwent three infusion experiments, on separate days and in random order.

Accuracy of noninvasive haemoglobin measurement by pulse oximetry depends on the type of infusion fluid.

Context: Measurement of blood haemoglobin concentration by pulse oximetry could be of value in determining when erythrocytes should be transfused during surgery, but the effect of infusion fluids on the results is unclear.

Objective: To study the effect of crystalloid and colloid fluid on the accuracy (bias) and precision of pulse oximetry haemoglobin estimation to indicate the venous haemoglobin concentration in volunteers.

Design: Open interventional crossover study.

Accuracy of noninvasive haemoglobin measurement by pulse oximetry depends on the type of infusion fluid.

Context: Measurement of blood haemoglobin concentration by pulse oximetry could be of value in determining when erythrocytes should be transfused during surgery, but the effect of infusion fluids on the results is unclear.

Objective: To study the effect of crystalloid and colloid fluid on the accuracy (bias) and precision of pulse oximetry haemoglobin estimation to indicate the venous haemoglobin concentration in volunteers.

Design: Open interventional crossover study.

Detection of dehydration by using volume kinetics.

Background: Patients admitted to surgery may be dehydrated, which is difficult to diagnose except when it is severe (>5% Gl116 of the body weight). We hypothesized that modest dehydration can be detected by kinetic analysis of the blood hemoglobin concentration after a bolus infusion of crystalloid fluid.

Methods: Four series of experiments were performed on 10 conscious, healthy male volunteers.