Background Changes in acid-base balance caused by infusion of a 0.9% saline solution during anesthesia and surgery are poorly characterized. Therefore, the authors evaluated these phenomena in a dose-response study. Methods Two groups of 12 patients each who were undergoing major intraabdominal gynecologic surgery were assigned randomly to receive 0.9% saline or lactated Ringer's solution in a dosage of 30 ml x kg(-1) x h(-1). The pH, arterial carbon dioxide tension, and serum concentrations of sodium, potassium, chloride, lactate, and total protein were measured in 30-min intervals. The serum bicarbonate concentration was calculated using the Henderson-Hasselbalch equation and also using the Stewart approach from the strong ion difference and the amount of weak plasma acid. The strong ion difference was calculated as serum sodium + serum potassium - serum chloride - serum lactate. The amount of weak plasma acid was calculated as the serum total protein concentration in g/dl x 2.43. Results Infusion of 0.9% saline, but not lactated Ringer's solution, caused a metabolic acidosis with hyperchloremia and a concomitant decrease in the strong ion difference. Calculating the serum bicarbonate concentration using the Henderson-Hasselbalch equation or the Stewart approach produced equivalent results. Conclusions Infusion of approximately 30 ml x kg(-1) x h(-1) saline during anesthesia and surgery inevitably leads to metabolic acidosis, which is not observed after administration of lactated Ringer's solution. The acidosis is associated with hyperchloremia.

Rapid saline infusion produces hyperchloremic acidosis in patients undergoing gynecologic surgery

Objective:We compared the effects of intravenous infusions of 0.9% saline ([Cl−] 154 mmol/L) and Plasma-Lyte 148 ([Cl−] 98 mmol/L, Baxter Healthcare) on renal blood flow velocity and perfusion in humans using magnetic resonance imaging (MRI).Background:Animal experiments suggest that hyperchloremia

A randomized, controlled, double-blind crossover study on the effects of 2-L infusions of 0.9% saline and plasma-lyte® 148 on renal blood flow velocity and renal cortical tissue perfusion in healthy volunteers.

Chronic obstructive pulmonary disease (COPD) is a major health care problem. Formerly mainly a disease of men, women are increasingly frequently afflicted. In many of these patients, exercise intolerance is the chief complaint. Few effective therapies are available. In recent years, dysfunction of the muscles of ambulation has been identified as a source of a portion of the exercise intolerance these patients experience, and this dysfunction has been shown to be, at least in part, remediable. Mechanisms inducing muscle dysfunction include disuse atrophy, malnutrition, low levels of anabolic steroids, and myopathy from corticosteroid use. Endurance exercise training has been conclusively demonstrated to improve exercise tolerance in COPD. Recent studies suggest that strength training is beneficial as well. A new frontier of therapy for muscle dysfunction in COPD is the use of anabolic hormones. Testosterone supplementation has been shown to increase muscle mass and strength in both hypogonadal and eugonadal healthy men. Low-dose testosterone supplementation is being considered for use in postmenopausal women. Though short-term administration of testosterone in moderate doses seems to be well tolerated in both men and women, further studies are required before safety and effectiveness can be established for routine use in COPD patients.

Skeletal muscle dysfunction in chronic obstructive pulmonary disease.

Biodiversity is a challenging field of research. Approaches are manifold and mostly cover few aspects of the total wealth of phenomena only. The mapping of the vascular plants and the inventory of Basidiomycota in Bavaria are projects to be mentioned in this context as one part of the commitment of the author. In the following article the author describes further activities during his lifework in regard A. Bresinsky (*) Institute of Botany of University of Regensburg, D-93040, Regensburg, Germany e-mail: abresinsky@t-online.de U. Lüttge et al. (eds.), Progress in Botany, Progress in Botany 75, DOI 10.1007/978-3-642-38797-5_1, © Springer-Verlag Berlin Heidelberg 2014 3 to ant–plant interactions resulting in dispersal and distribution of plants, and moreover, in respect to speciation and to evolution of high ranked taxa within the fungi, discussed mainly in relation to the genus Pleurotus and the order Boletales. In fungi the investigations include breeding systems, isolation barriers, polyploidy, pigment patterns and DNA phylogeny. The pigment patterning in Boletales correlates well with the phylogeny as revealed by DNA analysis of selected gene sections.

Progress in Botany

Cerebral blood flow (CBF) and its distribution are highly sensitive to changes in the partial pressure of arterial CO2 (PaCO2). This physiological response, termed cerebrovascular CO2 reactivity, i...

Integration of cerebrovascular CO2 reactivity and chemoreflex control of breathing: mechanisms of regulation, measurement, and interpretation

Quantitative analysis of ionic solutions in terms of physical and chemical principles has been effectively prohibited in the past by the overwhelming amount of calculation it required, but computers have suddenly eliminated that prohibition. The result is an approach to acid-base which revolutionizes our ability to understand, predict, and control what happens to hydrogen ions in living systems. This review outlines that approach and suggests some of its most useful implications. Quantitative understanding requires distinctions between independent variables (in body fluids: pCO2, net strong ion charge, and total weak acid, usually protein), and dependent variables [( HCO-3], [HA], [A-], [CO(2-)3], [OH-], and [H+] (or pH]. Dependent variables are determined by independent variables, and can be calculated from the defining equations for the specific system. Hydrogen ion movements between solutions can not affect hydrogen ion concentration; only changes in independent variables can. Many current models for ion movements through membranes will require modification on the basis of this quantitative analysis. Whole body acid-base balance can be understood quantitatively in terms of the three independent variables and their physiological regulation by the lungs, kidneys, gut, and liver. Quantitative analysis also shows that body fluids interact mainly by strong ion movements through the membranes separating them.

Peter A. Stewart

Papers

Modern quantitative acid–base chemistry

Erratum: Modern quantitative acid–base chemistry