Patients with sepsis have typically reduced concentrations of hemoglobin and albumin, the major components of noncarbonic buffer power (β). This could expose patients to high pH variations during acid-base disorders. The objective of this study is to compare, in vitro, noncarbonic β of patients with sepsis with that of healthy volunteers, and evaluate its distinct components. Whole blood and isolated plasma of 18 patients with sepsis and 18 controls were equilibrated with different CO2 mixtures. Blood gases, pH, and electrolytes were measured. Noncarbonic β and noncarbonic β due to variations in strong ion difference (βSID) were calculated for whole blood. Noncarbonic β and noncarbonic β normalized for albumin concentrations (βNORM) were calculated for isolated plasma. Representative values at pH = 7.40 were compared. Albumin proteoforms were evaluated via two-dimensional electrophoresis. Hemoglobin and albumin concentrations were significantly lower in patients with sepsis. Patients with sepsis had lower noncarbonic β both of whole blood (22.0 ± 1.9 vs. 31.6 ± 2.1 mmol/L, P < 0.01) and plasma (0.5 ± 1.0 vs. 3.7 ± 0.8 mmol/L, P < 0.01). Noncarbonic βSID was lower in patients (16.8 ± 1.9 vs. 24.4 ± 1.9 mmol/L, P < 0.01) and strongly correlated with hemoglobin concentration (r = 0.94, P < 0.01). Noncarbonic βNORM was lower in patients [0.01 (-0.01 to 0.04) vs. 0.08 (0.06-0.09) mmol/g, P < 0.01]. Patients with sepsis and controls showed different amounts of albumin proteoforms. Patients with sepsis are exposed to higher pH variations for any given change in CO2 due to lower concentrations of noncarbonic buffers and, possibly, an altered buffering function of albumin. In both patients with sepsis and healthy controls, electrolyte shifts are the major buffering mechanism during respiratory acid-base disorders.NEW & NOTEWORTHY Patients with sepsis are poorly protected against acute respiratory acid-base derangements due to a lower noncarbonic buffer power, which is caused both by a reduction in the major noncarbonic buffers, i.e. hemoglobin and albumin, and by a reduced buffering capacity of albumin. Electrolyte shifts from and to the red blood cells determining acute variations in strong ion difference are the major buffering mechanism during acute respiratory acid-base disorders.

• Klíčová slova
• acid-base equilibrium, acidosis, respiratory, buffers, electrolytes, sepsis,
• MeSH
• acidobazická rovnováha MeSH
• analýza krevních plynů MeSH
• koncentrace vodíkových iontů MeSH
• kyseliny MeSH
• lidé MeSH
• poruchy acidobazické rovnováhy * MeSH
• sepse * MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• kyseliny MeSH

BACKGROUND: Metabolic acidosis (MAC) is a common aspect of dialysis-dependent patients. It is definitely caused by acid retention; however, the influence of other plasma ions is unclear. Understanding the mechanism of MAC and its correction is important when choosing the dialysis solution. Therefore, we assessed the relationship between intradialytic change of acid-base status and serum electrolytes. METHODS: We studied 68 patients on post-dilution hemodiafiltration, using dialysate bicarbonate concentration 32mmol/L. The acid-base disorders were evaluated by the traditional Siggaard-Anderson and modern Stewart approaches. RESULTS: The mean pre-dialysis pH was 7.38, standard base excess (SBE) -1.5, undetermined anions (UA(-)) 7.5, sodium-chloride difference (Diff(NaCl)) 36.2mmol/L. MAC was present in 34% of patients, of which 83% had an increased UA(-) as a major cause of MAC. The mean nPCR was 0.99g/kg/day and correlated negatively with SBE. After dialysis, metabolic alkalosis predominated in 81%. The mean post-dialysis pH was 7.45, SBE 4, UA(-) 2.6, Diff(NaCl) 36.9mmol/L. ΔSBE significantly correlated with ΔUA(-), but not with ΔDiff(NaCl) or ΔCl(-). CONCLUSIONS: MAC in patients on hemodiafiltration is mainly caused by acid retention and is associated with higher protein intake. We did not prove the effect of sodium or chloride on acid-base balance. Even though we used a relatively low concentration of dialysate bicarbonate, we recorded a high proportion of post-dialysis alkalosis caused by the excessive decrease of undetermined anions, which had been completely replaced by bicarbonate and indicated the elimination of undesirable anions, as well as of normal endogenous anions.

• Klíčová slova
• Acid-base, Base excess, Electrolyte, Hemodiafiltration, Sodium-chloride difference, Stewart,
• MeSH
• chronické selhání ledvin komplikace   terapie   MeSH
• elektrolyty krev   MeSH
• hemodiafiltrace škodlivé účinky   MeSH
• lidé středního věku MeSH
• lidé MeSH
• poruchy acidobazické rovnováhy etiologie   MeSH
• senioři MeSH
• Check Tag
• lidé středního věku MeSH
• lidé MeSH
• mužské pohlaví MeSH
• senioři MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• elektrolyty MeSH

Traditional diagnostic approach to acute acid-base disorders is based on the assessment of bicarbonate buffer system, in which pH is determined by the ratio of [HCO3-] to pCO2. This, in turn, creates basis for distinguishing metabolic and respiratory disorders, and defines the term “compensation”. The use of electroneutrality advantageously complements the bicarbonate-based approach when dealing with complex acid-base disorders. It is possible to simplify this approach so it can be applied only using mental arithmetics. In principle, the space created by strong ion difference (which can be simplified to [Na+]-[Cl-]) is shared by negative charges on albumin and bicarbonate. In turn, a shrinkage of this space ([Na+]-[Cl-] 36 mM causes alka-losis, as well as a decrease in albumin concentration (for every 10 g/L of albumin, 3 mM is freed to be occupied by [HCO3-]). Lastly, if the sum of negative charges on albumin and [HCO3-] is lower than estimated strong ion difference, an unmeasured anion must be present. This concept is explained on commented case reports.

• Klíčová slova
• acid base equilibrium, electroneutrality, interal environment,
• MeSH
• acidobazická rovnováha MeSH
• hydrogenuhličitany MeSH
• koncentrace vodíkových iontů MeSH
• lidé MeSH
• poruchy acidobazické rovnováhy * diagnóza   MeSH
• sodík MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• hydrogenuhličitany MeSH
• sodík MeSH

BACKGROUND: The acidity of human body fluids, expressed by the pH, is physiologically regulated in a narrow range, which is required for the proper function of cellular metabolism. Acid-base disorders are common especially in intensive care, and the acid-base status is one of the vital clinical signs for the patient management. Because acid-base balance is connected to many bodily processes and regulations, complex mathematical models are needed to get insight into the mixed disorders and to act accordingly. The goal of this study is to develop a full-blood acid-base model, designed to be further integrated into more complex human physiology models. RESULTS: We have developed computationally simple and robust full-blood model, yet thorough enough to cover most of the common pathologies. Thanks to its simplicity and usage of Modelica language, it is suitable to be embedded within more elaborate systems. We achieved the simplification by a combination of behavioral Siggaard-Andersen's traditional approach for erythrocyte modeling and the mechanistic Stewart's physicochemical approach for plasma modeling. The resulting model is capable of providing variations in arterial pCO2, base excess, strong ion difference, hematocrit, plasma protein, phosphates and hemodilution/hemoconcentration, but insensitive to DPG and CO concentrations. CONCLUSIONS: This study presents a straightforward unification of Siggaard-Andersen's and Stewart's acid-base models. The resulting full-blood acid-base model is designed to be a core part of a complex dynamic whole-body acid-base and gas transfer model.

• Klíčová slova
• Acid-base modeling, Behavioral acid-base, Modelica, Physicochemical acid-base, Physiolibrary, Physiology, Siggaard-Andersen,
• MeSH
• acidobazická rovnováha * fyziologie   MeSH
• biologické modely * MeSH
• chemické modely * MeSH
• koncentrace vodíkových iontů MeSH
• lidé MeSH
• poruchy acidobazické rovnováhy diagnóza   epidemiologie   patofyziologie   MeSH
• teoretické modely * MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

A quantitative evaluation of metabolic acid-base component is described. The model is based on Stewart's analysis of acid-base chemistry. The metabolic component of acid-base disturbances is divided into four partial metabolic disorders; they can result from abnormal concentrations of chloride, albumin and phosphate disturbances, or from appearance of abnormal unidentified strong anions. The efficiency of the model is sufficient, quantitative partial results are given in the same units as base excess. In complex acid-base disturbances, such as are seen in critically ill patients, a detailed analysis of the specific components of the metabolic acid-base status allows one to plan specific therapeutic interventions.

• MeSH
• acidobazická rovnováha * MeSH
• acidóza laktátová krev   MeSH
• acidóza krev   etiologie   MeSH
• algoritmy MeSH
• alkalóza krev   etiologie   MeSH
• anionty krev   MeSH
• biochemické jevy MeSH
• biochemie MeSH
• chemické modely * MeSH
• chloridy krev   MeSH
• draslík krev   MeSH
• fosfáty krev   MeSH
• hořčík krev   MeSH
• hydrogenuhličitany krev   MeSH
• hypofosfatemie krev   komplikace   MeSH
• ketóza krev   MeSH
• kritický stav MeSH
• lidé MeSH
• lineární modely MeSH
• poruchy acidobazické rovnováhy krev   metabolismus   terapie   MeSH
• sérový albumin analýza   MeSH
• sodík krev   MeSH
• vápník krev   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• anionty MeSH
• chloridy MeSH
• draslík MeSH
• fosfáty MeSH
• hořčík MeSH
• hydrogenuhličitany MeSH
• sérový albumin MeSH
• sodík MeSH
• vápník MeSH

Acid-base disorders were studied in two groups of dairy cows. According to conventional interpretation in the 1st group of dairy cows (n = 10) the results of the acid-base parameters indicated respiratory alkalosis and in the 2nd group (n = 10) metabolic acidosis. The data of the two groups were examined using principal component analysis. So called "reduced variables"--principal components for each animal were calculated. Each experimental animal was projected in the coordinates of 3 principal components K1, K2 and K3. The components K1, K2 and K3 comprised a 90% data variability. The importance of variables for a dividing of groups (1 and 2) was quantified. The most important were pCO2, (HCO3)' and BE. It was proved according to mathematico-empiric equations that dairy cows of 1st group suffered from acute respiratory alkalosis. In the 2nd group of dairy cows the combined acid-base disorder was confirmed using the equations for metabolic acidosis and chronic respiratory acidosis. The use of PCA method and empiric equations for acid-base imbalances shows the possibilities for gaining new knowledge how to make the diagnostic process more exact.

• MeSH
• biologické modely MeSH
• mlékárenství MeSH
• nemoci skotu metabolismus   MeSH
• poruchy acidobazické rovnováhy metabolismus   veterinární   MeSH
• skot MeSH
• statistika jako téma MeSH
• zvířata MeSH
• Check Tag
• skot MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH

BACKGROUND: Evaluation of acid-base disorders using the Stewart-Fencl principle is based on assessment of independent factors: strong ion difference (SID) and the total concentration of non-volatile weak acids (Atot). This approach allows for a more detailed evaluation of the cause of acid-base imbalance than the conventional bicarbonate-centered approach based on the Henderson-Hasselbalch principle, which is a necessary yet insufficient condition to describe the state of the system. The aim of our study was to assess acid-base disorders in peritoneal dialysis (PD) patients using both of these principles. METHODS: A total of 17 patients with chronic renal failure (10 men), aged 60.7 (22-84) years, treated by PD for 25.7 (1-147) months were examined. A control group included 17 healthy volunteers (HV) (8 males), with a mean age of 42.7 (22-77) years and normal renal function. Patients were treated with a solution containing bicarbonate (25 mmol/L) and lactate (15 mmol/L) as buffers; eleven of them used, during the nighttime dwell, a solution with icodextrin buffered by lactate at a concentration of 40 mmol/L. The following equations were employed for calculations of acid-base parameters according to the Stewart-Fencl principle. The first is SID = [Na+] + [K+] + 2[Ca(2+)] + 2[Mg(2+)] - [Cl-] - [UA-], where SID is the strong ion difference and [UA-] is the concentration of undetermined anions. For practical calculation of SID, the second equation, SID = [HCO3-] + [Alb-] + [Pi-], was used, where [Alb-] and [Pi-] are the charges carried by albumin and phosphates. The third is Atot, the total concentration of weak non-volatile acids, albumin [Alb] and phosphates [Pi]. RESULTS: The capillary blood pH in PD group was 7.41 (7.27-7.48), [HCO3-] levels 23.7 (17.6-29.5) mmol/L, SID 36.3 (29.5-41.3) mmol/L, sodium-chloride difference 39.0 (31.0-44.0) mmol/L, [Pi] 1.60 (0.83-2.54) mmol/L, and [Alb] 39.7 (28.8-43.4) g/L (median, min-max). Bicarbonate in blood correlated positively with SID (Rho = 0.823; p < 0.001), with the sodium-chloride difference (Rho = 0.649; p < 0.01) and pH (Rho = 0.754; p < 0.001), and negatively with residual renal function (Rho = -0.517; p < 0.05). Moreover, the sodium-chloride difference was also found to correlate with SID (Rho = 0.653; p < 0.01). While the groups of PD and HV patients did not differ in median bicarbonate levels, significantly lower median value of SID were observed in PD patients, 36.3 vs. 39.3 mmol/L (p < 0.01); additionally, PD patients were shown to have significantly lower mean value of serum sodium levels, 138 vs. 141 mmol/L (p < 0.01), and serum chlorides levels, 100 vs. 104 mmol/L (p < 0.001). Despite the higher [UA-] levels in PD patients, 9.1 vs. 5.4 mmol/L (p < 0.001), this parameter was not found to correlate with bicarbonate levels. CONCLUSIONS: The results suggest that the decreased bicarbonate in PD patients results from a combination of decreased sodium-chloride difference and mildly increased unmeasured anions.

• MeSH
• acidobazická rovnováha MeSH
• chronické selhání ledvin komplikace   terapie   MeSH
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• peritoneální dialýza * MeSH
• poruchy acidobazické rovnováhy etiologie   terapie   MeSH
• senioři nad 80 let MeSH
• senioři MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mužské pohlaví MeSH
• senioři nad 80 let MeSH
• senioři MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

The author describes and evaluates basic parameters used for evaluation of the acid-base balance: pH, pCO2, BE, BBS, (Na + K)/Cl, (AG) and RA. He compares the theories of two basic schools, the Copenhagen and Boston school and synthesizes the different views of various authors. A combination of modern theories permits to evaluate simple and combined disorders of the acid-base balance, disorders which can potentiate each other but also mask their effect. The author mentions also the importance of oxygen parameters and of other substances essential for obtaining energy, the importance of assessment of the patient's clinical condition, the necessity of retrospective evaluation based on the trend of changes of the acid-base balance in the course of time. In the article mathematical logical terminology of acid-base balance disorders is used, the attached figures and calculations facilitate the understanding of this pretentious problem.

• MeSH
• acidobazická rovnováha fyziologie   MeSH
• anionty MeSH
• koncentrace vodíkových iontů MeSH
• lidé MeSH
• oxid uhličitý metabolismus   MeSH
• poruchy acidobazické rovnováhy metabolismus   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• anglický abstrakt MeSH
• časopisecké články MeSH
• Názvy látek
• anionty MeSH
• oxid uhličitý MeSH

In patients with advanced cirrhosis with ascites disorders of water and electrolyte metabolism are often present and they are associated with changes in acid-base balance. These changes can be very complicated, their diagnosis and treatment difficult. Dilutional hyponatremia is the most common disorder. Hyponatremia in these patients is associated with increased morbidity and mortality before and after liver transplantation. Other common disorders include hyperchloremic acidosis, hypokalemia, metabolic alkalosis, lactic acidosis, respiratory alkalosis. If renal impairment occurs (for example hepatorenal syndrome), metabolic acidosis and retention of acid metabolites may develop. The pathogenesis of these conditions applies primarily hemodynamic changes. Activation of renin-angiotensin-aldosterone system and non-osmotic stimulation of antidiuretic hormone trigger serious changes in water and natrium-chloride metabolism. This activation is clinically expressed like oedema, ascites, hydrothorax, low to zero natrium concentration in urine and increased urinary osmolality, which is higher than serum osmolality. In practice, the evaluation can be significantly modified by the ongoing diuretic therapy. Closer monitoring of water and electrolyte metabolism together with acid-base balance in patients with ascitic liver cirrhosis is important, not only in terms of diagnosis but especially in terms of therapy.

• Klíčová slova
• acid-base balance diuretic therapy., ascitic liver cirrhosis, dilutional hyponatremia, retention of solute-free water,
• MeSH
• acidobazická rovnováha * MeSH
• elektrolyty MeSH
• hyponatremie * etiologie   MeSH
• jaterní cirhóza * komplikace   patofyziologie   MeSH
• lidé MeSH
• voda MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• elektrolyty MeSH
• voda MeSH

• MeSH
• acidobazická rovnováha * MeSH
• acidóza MeSH
• alkalóza MeSH
• dítě MeSH
• kojenec MeSH
• lidé MeSH
• novorozenec MeSH
• předškolní dítě MeSH
• Check Tag
• dítě MeSH
• kojenec MeSH
• lidé MeSH
• novorozenec MeSH
• předškolní dítě MeSH
• Publikační typ
• časopisecké články MeSH
• přehledy MeSH