El regulador de transmembrana de fibrosis quística (CFTR) disfuncional y sus efectos extrapulmonares / The dysfunction of transmembrane regulator in cystic fibrosis (CFTR) and its extrapulmonary effects

El daño del regulador de transmembrana de fibrosis quística (CFTR) puede causar una enfermedad grave fuera de los pulmones. El canal de cloruro (Cl-) ha sido el más estudiado, sin embargo, el bicarbonato (HCO3 -) tiene un rol muy importante en el comportamiento de las secreciones y la inflamación secundaria. El hecho de que CFTR funcione no sólo como un canal de Cl- sino también de HCO3- es un campo para la investigación y el desarrollo de fármacos para pacientes con daño genético o adquirido, este último frecuente en la población general. Algunos moduladores de CFTR pueden tener un beneficio terapéutico en el tratamiento de pancreatitis en ambas situaciones. La disfunción del CFTR a nivel renal puede resultar excepcionalmente en alcalosis metabólica y reducción del impulso ventilatorio. Hasta la fecha no está claro cuales serian sus efectos en los sistemas gastrointestinal y hepatobiliar.

Transmembrane regulator in cystic fibrosis (CFTR) can cause severe disease outside of the lungs. The chloride channel (Cl-) has been the most studied, however bicarbonate (HCO3 -) has a very important role in the behavior of secretions and secondary inflammation. The fact that CFTR works not only as a Cl- channel but also as an HCO3- channel is a field for research and development of drugs for patients with genetic or acquired damage, the latter frequent in the general population. Some CFTR modulators may have a therapeutic benefit in the treatment of pancreatitis in both situations. CFTR dysfunction at the renal level can exceptionally result in metabolic alkalosis and reduced ventilatory drive. To date it is not clear what its effects on the gastrointestinal and hepatobiliary systems would be.

Bicarbonato de sodio intravenoso ¿Cuándo, cómo y por qué utilizarlo? / Intravenous sodium bicarbonate. When, how and why to use it?

Severe metabolic acidosis is defined by a pH < 7.2 with HCO3− < 8 mE- q/L in plasma. Its best treatment is to correct the underlying cause. However, acidemia produces multiple complications such as resistance to the action of catecholamines, pulmonary vasoconstriction, impaired cardiovascular function, hyperkalemia, immunological dysregulation, respiratory muscle fatigue, neurological impairment, cellular dysfunction, and finally, it contributes to multisystemic failure. Intravenous NaHCO3 buffers severe acidemia, preventing the associated damage and gains time while the causal disease is corrected. Its indication requires a risk-benefit assessment, considering its complications. These are hypernatremia, hypokalemia, ionic hypocalcemia, rebound alkalosis, and intracellular acidosis. For this reason, therapy must be "adapted" and administered judiciously. The patient will require monitoring with serial evaluation of the internal environment, especially arterial blood gases, plasma electrolytes, and ionized calcium. Isotonic solutions should be preferred instead of hypertonic bicarbonate. The development of hypernatremia must be prevented, calcium must be provided for hypocalcemia to improve cardiovascular function. Furthermore, in mechanically ventilated patients, a respiratory response similar to the one that would develop physiologically, must be established to be able to extract excess CO2 and thus avoid intracellular acidosis. It is possible to estimate the bicarbonate deficit, speed, and volume of its infusion. However, the calculations are only for reference. More important is to start intravenous NaHCO3 when needed, administer it judiciously, manage its side effects, and continue it to a safe goal. In this review we address all the necessary elements to consider in the administration of intravenous NaHCO3, highlighting why it is the best buffer for the management of severe metabolic acidosis.

Effects of different electrolyte solutions on blood washing in cardiac surgery with cardiopulmonary bypass / 中华麻醉学杂志

Objective:To evaluate the effects of different electrolyte solutions on blood washing in cardiac surgery with cardiopulmonary bypass (CPB).Methods:Sixty patients, aged 18-80 yr, weighing 50-100 kg, undergoing cardiac surgery with CPB with expected banked blood transfusion 4-6 U in our hospital, were divided into 3 groups ( n=20 each) by a random number table method: compound electrolyte injection group (group A), sodium bicarbonate Ringer′s solution group (group B) and normal saline group (group C). Banked blood and salvaged autologous blood were washed with compound electrolyte injection, sodium bicarbonate Ringer′s solution and normal saline.Banked and autologous blood was collected before washing and immediately after washing for blood gas analysis.The osmotic fragility of red blood cells was measured by colorimetry, and the concentration of 2, 3-diphosphoglycerate (2, 3-DPG) was determined by enzyme-linked immunosorbent assay. Results:Compared with the baseline before washing, the concentrations of K +, Glu and Lac in banked blood were significantly decreased, the concentrations of K + in banked blood were increased, and the concentrations of Glu and Lac in autologous blood were decreased, the osmotic fragility of erythrocytes was increased, and the concentrations of 2, 3-DPG in banked and autologous blood were increased after washing in the three groups ( P<0.05). Compared with group C, the concentrations of Na + and Cl - in banked and autologous blood were significantly decreased, the concentrations of K + in banked and autologous blood were increased, the osmotic fragility of erythrocytes in banked and autologous blood was decreased, and the concentrations of 2, 3-DPG in banked and autologous blood were increased in A and B groups ( P<0.05). Compared with A and C groups, BE in banked and autologous blood were significantly increased after washing in group B than in A and C groups ( P<0.05). After washing, Ca 2+ was detected in banked and autologous blood in group B, however, Ca 2+ was not detected in banked and autologous blood in group A and group C. Conclusions:Compound electrolyte solution and sodium bicarbonate Ringer′s solution provide better efficacy when used for blood washing in cardiac surgery with CPB, and sodium bicarbonate Ringer′s solution can also improve the acidic and calcium-free internal environment of blood.

Role of HCO3- umbrella in the pathogenesis of primary biliary cholangitis / 临床肝胆病杂志

Primary biliary cholangitis (PBC) is an autoimmune disease. Although PBC has the features of autoimmune disease, it has poor response to immunosuppressants and good response to the drugs participating in bile acid metabolism, such as ursodeoxycholic acid. Studies have shown that the bicarbonate secretion of biliary epithelial cells is impaired in PBC patients, and bile acid not blocked by HCO3- umbrella enters biliary epithelial cells and mediates their damage and apoptosis, leading to the expression of autoantibodies in apoptotic cells and immunologic injury. In order to explore the role of HCO3- umbrella secreted by biliary epithelial cells in the pathogenesis of PBC, this article briefly introduces the physiological function and production mechanism of HCO3- umbrella and the influencing factors for HCO3- secretion, and it is pointed out that reduced HCO3- secretion may be a key link in the pathogenesis of PBC and a potential therapeutic target.

Concordance analysis between dosed serum bicarbonate and that calculated by gas analysis in chronic renal patients / Análise de concordância entre o bicarbonato sérico dosado e o calculado pela gasometria em pacientes renais crônicos

Abstract Introduction: The control of metabolic acidosis in dialysis patients focuses on the supply of bicarbonate during the dialysis session, and it is not standard in all hemodialysis to assess serum bicarbonate concentrations. Bicarbonate expressed in blood gas analysis is the most sensitive standard of analysis and it is measured indirectly, using the Henderson-Hasselbalch equation. There are no studies in this population evaluating the concordance between the calculated bicarbonate with the direct method of biochemical analysis. The aim of this study was to analyze the concordance between the measured and calculated serum bicarbonate levels using blood gas analysis. Methods: We analyzed blood samples from chronic kidney patients undergoing hemodialysis, using the same sample of bicarbonate analysis by biochemistry and gasometry. The concordance was assessed using the Bland-Altman method. Results: 51 samples were analyzed. The analysis revealed a high correlation (r = 0.73) and a mean difference (bias) of 1.15 ± 3 mmol/L. The median time between collection and examination was 241 minutes. Discussion: We can conclude that the biochemical bicarbonate analysis compared to that calculated from blood gas analysis in chronic renal patients was consistent. For greater concordance between the data, it is important that the time between the collection of the samples and the referral to the laboratory for carrying out the dosages does not exceed four hours. The serum bicarbonate dosage can result in cost savings when compared to that of bicarbonate in blood gas analysis.

Resumo Introdução: O controle da acidose metabólica em pacientes dialíticos está voltado, principalmente, para o suprimento de bicarbonato durante a sessão de diálise, não sendo padrão em todas as hemodiálises avaliar as concentrações séricas do bicarbonato. O bicarbonato expresso na gasometria é considerado o padrão mais sensível de análise e é medido indiretamente por meio da equação de Henderson-Hasselbalch. Não há estudos nessa população avaliando a concordância do bicarbonato calculado com o método direto de análise bioquímica. O objetivo deste estudo é analisar a concordância entre o bicarbonato sérico medido e o calculado por meio da gasometria. Métodos: Foram analisadas amostras de sangue de pacientes renais crônicos em hemodiálise sendo feito na mesma amostra de análise do bicarbonato pela bioquímica e análise pela gasometria. A concordância foi avaliada pelo método de Bland-Altman. Resultados: Foram analisados um total de 51 amostras. A análise de correlação revelou alta correlação (r = 0.73) e a diferença média (bias) de 1.15 ± 3 mmol/L. O tempo mediano entre a realização da coleta e do exame foi de 241 minutos. Discussão: Podemos concluir que a realização da dosagem bioquímica do bicarbonato comparada com a calculada a partir da gasometria em pacientes renais crônicos foi concordante. Para maior concordância entre os dados, é importante que o tempo entre a coleta das amostras e o encaminhamento ao laboratório para a realização das dosagens não exceda quatro horas. A dosagem do bicarbonato sérico pode resultar numa economia de custos comparada à do bicarbonato da gasometria.

Effects of estrogen on bicarbonate secretion of duodenal mucosa / 中华消化杂志

Objective@#To study the effects of estrogen on bicarbonate secretion of duodenal mucosal, and to observe estrogen receptor (ER) subtypes of estrogen.@*Methods@#Sixteen 4-week-old male C57 mice were divided into control group and estrogen group, with eight mice in each group. The mice serum level of estrogen was detected by chemiluminescence. The expression of cystic fibrosis transmembrane conductance regulator (CFTR), solute carrier family 26 (SLC26) A3 and SLC26A6 in the duodenum tissues were determined by real-time polymerase chain reaction (RT-PCR). After SCBN cells treated with estrogen, ERα and ERβ blocking agent, and transfected with silenced ERα and ERβ for 24 and 48 hours, the expression levels of CFTR, SLC26A3 and SLC26A6 mRNA in cells were detected by RT-PCR. The effects of estrogen before and after silenced ERα and ERβ on bicarbonate secretion of SCBN cells were observed by high-speed ion imaging system. T test and rank sum test were used for statistical analysis.@*Results@#Compared with that of control group, the serum estrogen level of estrogen group was significantly high ((4 874±942) pmol/L vs. (657±187) pmol/L, t=-11.579, P<0.01). The expression levels of CFTR, SLC26A3 and SLC26A6 mRNAs in duodenum tissues of estrogen group were higher than those of control group (0.856±0.302 vs. 0.452±0.246, 2.910±1.680 vs. 1.120±0.540, 1.272±0.667 vs. 0.319±0.114), and the differences were statistically significant (t=-2.317, -2.483 and -3.721, all P<0.05). Compared with those treated with estrogen for 24 and 48 hours, the levels of CFTR mRNA and SLC26A6 mRNA were lower after the ERβ blocking agent were added into estrogen for 24 and 48 hours (CFTR mRNA: 0.171±0.059 vs. 0.522±0.260 and 0.111±0.014 vs. 0.578±0.297; SLC26A6 mRNA: 0.486±0.289 vs. 1.118±0.571 and 0.492±0.231 vs. 1.551±0.605), and the differences were statistically significant (tCFTR mRNA=2.974 and 2.655, tSLC26A6 mRNA=2.393 and 3.272; all P<0.05). Compared with those of silenced ERα group, the levels of CFTR mRNA, SLC26A3 mRNA and SLC26A6 mRNA were higher after ERα silenced and then added estrogen for 24 and 48 hours (24 h: 5.073±2.270 vs. 1.185±0.494, 1.796±1.168 vs. 0.468±0.108 and 3.085±1.357 vs. 0.706±0.347; 48 h: 5.025±1.998 vs. 1.185±0.494, 1.557±0.653 vs. 0.468±0.108 and 3.290±1.750 vs. 0.706±0.347), and the differences were statistically significant (t24 h=-4.122, -2.773 and -4.162, t48 h=-4.604, -4.034 and -3.250; all P<0.05). Compared with that of silenced ERα group, the bicarbonate secretion increased after ERα silenced and then added estrogen for 24 and 48 hours (0.72±0.17 and 1.15±0.25 vs. 0.35±0.17), and pH also elevated, and the differences were statistically significant (t=-6.516 and -12.387, both P<0.01).@*Conclusion@#Estrogen mainly up-regulates the expression of bicarbonate transporter protein in duodenal mucosal epithelial cells through ERβ, and promotes the bicarbonate secretion of duodenal mucosa.

Effects of estrogen on bicarbonate secretion of duodenal mucosa / 中华消化杂志

Objective To study the effects of estrogen on bicarbonate secretion of duodenal mucosal , and to observe estrogen receptor (ER) subtypes of estrogen.Methods Sixteen 4-week-old male C57 mice were divided into control group and estrogen group , with eight mice in each group .The mice serum level of estrogen was detected by chemiluminescence .The expression of cystic fibrosis transmembrane conductance regulator (CFTR), solute carrier family 26 (SLC26) A3 and SLC26A6 in the duodenum tissues were determined by real-time polymerase chain reaction ( RT-PCR).After SCBN cells treated with estrogen , ERαand ERβblocking agent, and transfected with silenced ER αand ERβfor 24 and 48 hours, the expression levels of CFTR, SLC26A3 and SLC26A6 mRNA in cells were detected by RT-PCR.The effects of estrogen before and after silenced ER αand ERβon bicarbonate secretion of SCBN cells were observed by high-speed ion imaging system.T test and rank sum test were used for statistical analysis .Results Compared with that of control group , the serum estrogen level of estrogen group was significantly high ((4 874 ±942) pmol/L vs.(657 ±187) pmol/L,t＝-11.579, P?0.01). The expression levels of CFTR, SLC26A3 and SLC26A6 mRNAs in duodenum tissues of estrogen group were higher than those of control group (0.856 ±0.302 vs.0.452 ±0.246, 2.910 ±1.680 vs.1.120 ±0.540, 1.272 ± 0.667 vs.0.319 ±0.114), and the differences were statistically significant ( t ＝-2.317,-2.483 and-3.721, all P?0.05).Compared with those treated with estrogen for 24 and 48 hours, the levels of CFTR mRNA and SLC26A6 mRNA were lower after the ERβblocking agent were added into estrogen for 24 and 48 hours (CFTR mRNA: 0.171 ±0.059 vs.0.522 ±0.260 and 0.111 ±0.014 vs.0.578 ±0.297; SLC26A6 mRNA:0.486 ±0.289 vs.1.118 ±0.571 and 0.492 ±0.231 vs.1.551 ±0.605), and the differences were statistically significant (tCFTR mRNA＝2.974 and 2.655, tSLC26A6 mRNA＝2.393 and 3.272; all P?0.05).Compared with those of silenced ERαgroup, the levels of CFTR mRNA, SLC26A3 mRNA and SLC26A6 mRNA were higher after ERα silenced and then added estrogen for 24 and 48 hours (24 h: 5.073 ±2.270 vs.1.185 ±0.494, 1.796 ±1.168 vs.0.468 ±0.108 and 3.085 ±1.357 vs.0.706 ±0.347; 48 h: 5.025 ±1.998 vs.1.185 ±0.494, 1.557 ± 0.653 vs.0.468 ±0.108 and 3.290 ±1.750 vs.0.706 ±0.347), and the differences were statistically significant (t24 h＝-4.122,-2.773 and -4.162, t48 h ＝-4.604,-4.034 and -3.250; all P?0.05).Compared with that of silenced ERαgroup, the bicarbonate secretion increased after ER αsilenced and then added estrogen for 24 and 48 hours (0.72 ±0.17 and 1.15 ±0.25 vs.0.35 ±0.17), and pH also elevated, and the differences were statistically significant (t＝-6.516 and -12.387, both P?0.01).Conclusion Estrogen mainly up-regulates the expression of bicarbonate transporter protein in duodenal mucosal epithelial cells through ER β, and promotes the bicarbonate secretion of duodenal mucosa .

The Clinical Efficacy of a Pure Alginate Formulation (Lamina G) for Controlling Symptoms in Individuals with Reflux Symptoms: A Randomized Clinical Study

BACKGROUND/AIMS: Bicarbonate-containing alginate formulations are reported to be effective for controlling reflux symptoms. However, the efficacy of Lamina G alginate without gas production has not been reported. The aim is to evaluate the efficacy of a non-bicarbonate alginate in individuals with reflux symptoms without reflux esophagitis. METHODS: Participants who had experienced heartburn or regurgitation for 7 consecutive days were randomized to one of the following treatment groups: proton pump inhibitors (PPI) plus alginate (combination) or PPI plus placebo (PPI only). In addition, as a reference group, patients received placebo plus alginate (alginate only). The primary endpoint compared the percentage of patients with complete resolution of symptoms for the final 7 days of the treatment. Secondary endpoints compared changes in symptom score, symptom-free days during the treatment period, the Reflux Disease Questionnaire, Patient Assessment of Upper Gastrointestinal Disorders (PAGI)-Quality of Life and PAGI-Symptoms Severity Index scores, the investigator's assessment of symptoms, and incidence of adverse events. RESULTS: Complete resolution of heartburn or regurgitation was not significantly different between the combination and PPI only groups (58.7% vs 57.5%, p=0.903). The secondary endpoints were not significantly different between the two groups. Complete resolution of heartburn or regurgitation, did not differ between the alginate only reference group and the PPI only group (75.0% vs 57.5%, p=0.146). CONCLUSIONS: The addition of non-bicarbonate alginate to PPI was no more effective than PPI alone in controlling reflux symptoms.

Approximation of bicarbonate concentration using serum total carbon dioxide concentration in patients with non-dialysis chronic kidney disease

BACKGROUND: We investigated the relationship between serum total carbon dioxide (CO₂) and bicarbonate ion (HCO₃⁻) concentrations in pre-dialysis chronic kidney disease (CKD) patients and devised a formula for predicting low bicarbonate (HCO₃⁻< 24 mmol/L) and high bicarbonate (HCO₃⁻ ≥ 24 mmol/L) using clinical parameters. METHODS: In total, 305 samples of venous blood collected from 207 pre-dialysis patients assessed by CKD stage (G1 + G2, 46; G3, 50; G4, 51; G5, 60) were investigated. The relationship between serum total CO₂ and HCO₃⁻ concentrations was analyzed using Pearson’s correlation coefficient. An approximation formula was developed using clinical parameters correlated independently with HCO₃⁻ concentration. Diagnostic accuracy of serum total CO₂ and the approximation formula was evaluated by receiver operating characteristic curve analysis and a 2 × 2 table. RESULTS: Serum total CO₂ correlated strongly with HCO₃⁻ concentration (r = 0.91; P < 0.001). The following approximation formula was obtained by a multiple linear regression analysis: HCO₃⁻ (mmol/L) = total CO₂ − 0.5 × albumin − 0.1 × chloride − 0.01 × (estimated glomerular filtration rate + blood glucose) + 15. The areas under the curves of serum total CO₂ and the approximation formula for detection of low bicarbonate and high bicarbonate were 0.981, 0.996, 0.993, and 1.000, respectively. This formula had superior diagnostic accuracy compared with that of serum total CO₂ (86.6% vs. 81.3%). CONCLUSION: Serum total CO₂ correlated strongly with HCO₃⁻ concentration in pre-dialysis CKD patients. An approximation formula including serum total CO₂ showed superior diagnostic accuracy for low and high bicarbonate compared with serum total CO₂.

Metabolic acidosis in hemodialysis patients: a review / Acidose metabólica em pacientes em hemodiálise: uma revisão

Abstract Metabolic acidosis is highly prevalent in hemodialysis patients. The disorder is associated with increased mortality and its deleterious effects are already present in the predialysis phase of chronic kidney disease. Metabolic acidosis has been linked to progression of chronic kidney disease, changes in protein and glucose metabolism, bone and muscle disorders and cardiovascular disease. At present, the control of metabolic acidosis in hemodialysis is mainly focused on the supply of bicarbonate during dialysis session, but further studies are needed to set the optimum target serum bicarbonate and the best concentration of the bicarbonate dialysate. The present study reviews pathophysiological and epidemiological aspects of metabolic acidosis in hemodialysis patients and also addresses its adverse effects and treatment.

Resumo A acidose metabólica é altamente prevalente em pacientes em hemodiálise. A doença está associada com mortalidade aumentada e os seus efeitos deletérios já estão presentes na fase pré-diálise da doença renal crônica. A acidose metabólica tem sido associada a progressão da doença renal crônica, alterações no metabolismo das proteínas e da glicose, doenças ósseas e musculares e enfermidades cardiovasculares. Atualmente, o controle da acidose metabólica em hemodiálise está voltado principalmente para o suprimento de bicarbonato durante a sessão de diálise, porém, mais estudos são necessários para definir o bicarbonato sérico alvo ideal e a melhor concentração de bicarbonato do banho. O artigo revisa os aspectos fisiopatológicos e epidemiológicos da acidose metabólica em pacientes em hemodiálise e também aborda seus efeitos adversos e tratamento.

The impact of high serum bicarbonate levels on mortality in hemodialysis patients

BACKGROUND/AIMS: The optimal serum bicarbonate level is controversial for patients who are undergoing hemodialysis (HD). In this study, we analyzed the impact of serum bicarbonate levels on mortality among HD patients. METHODS: Prevalent HD patients were selected from the Clinical Research Center registry for End Stage Renal Disease cohort in Korea. Patients were categorized into quartiles according to their total carbon dioxide (tCO₂) levels: quartile 1, a tCO₂ of < 19.4 mEq/L; quartile 2, a tCO₂ of 19.4 to 21.5 mEq/L; quartile 3, a tCO₂ of 21.6 to 23.9 mEq/L; and quartile 4, a tCO₂ of ≥ 24 mEq/L. Cox regression analysis was used to calculate the adjusted hazard ratio (HR) and confidence interval (CI) for mortality. RESULTS: We included 1,159 prevalent HD patients, with a median follow-up period of 37 months. Kaplan-Meier analysis revealed that the all-cause mortality was significantly higher in patients from quartile 4, compared to those from the other quartiles (p = 0.009, log-rank test). The multivariate Cox proportional hazard model revealed that patients from quartile 4 had significantly higher risk of mortality than those from quartile 1, 2 and 3, after adjusting for the clinical variables in model 1 (HR, 1.99; 95% CI, 1.15 to 3.45; p = 0.01) and model 2 (HR, 1.82; 95% CI, 1.03 to 3.22; p = 0.04). CONCLUSIONS: Our data indicate that high serum bicarbonate levels (a tCO₂ of ≥ 24 mEq/L) were associated with increased mortality among prevalent HD patients. Further effort might be necessary in finding the cause and correcting metabolic alkalosis in the chronic HD patients with high serum bicarbonate levels.

Bicarbonate-versus lactate-buffered solutions for hemodiafiltration in acute renal failure:a meta-analysis / 中国组织工程研究

BACKGROUND:Hemodialysis therapy is an important means for the treatment of acute renal failure, which aims to remove excess water and toxins and maintain acid-base balance of a patient, creating conditions for medication and nutrition therapy while avoiding multiple organ failure. OBJECTIVE:To compare bicarbonate-and lactate-buffered solutions for acute continuous hemodiafiltration in acute renal failure. METHODS:A computer-based search was performed in PubMed, EMBASE, SCI, Cochrane Library, Chinese Biomedical Literature Database, China Journal Ful Text Database, Chinese Medical Association Journals for randomized control trials related to bicarbonate-versus lactate-buffered solutions for hemodiafiltration in acute renal failure published before January 2014. The quality of the included studies was evaluated by Cochrane Handbook, and data were analyzed by RevMan 5.1 from the Cochrane Col aboration. RESULTS AND CONCLUSION:Four studies (171 patients) met inclusion criteria. Overal , patients treated with bicarbonate-buffered solutions had fewer cardiovascular complications and symptomatic hypotension events as wel as lower serum lactate levels than patients who received lactate-buffered solutions (P<0.05). There were no differences in mortality, serum bicarbonate levels, serum creatinine, serum pH, carbon dioxide partial pressure. The current evidence shows that patients undergoing bicarbonate-buffered solutions may experience fewer cardiovascular complications and symptomatic hypotension. Given the limited research, it is insufficient to recommend for clinical use.

Correlation between peripheral venous and arterial blood gas measurements in patients admitted to the intensive care unit: A single-center study

BACKGROUND: The objective of this study was to examine the correlation between arterial blood gas (ABG) and peripheral venous blood gas (VBG) samples for all commonly used parameters in patients admitted to a medical intensive care unit (ICU). METHODS: A single-center, prospective trial was carried out in a medical ICU in order to determine the level of correlation of ABG and peripheral VBG measurements. A maximum of five paired ABG-VBG samples were obtained per patient to prevent a single patient from dominating the data set. RESULTS: Regression equations were derived to predict arterial values from venous values as follows: arterial pH=-1.108+1.145xvenous pH+0.008xPCO2-0.012xvenous HCO3+0.002xvenous total CO2 (R2=0.655), arterial PCO2=88.6-10.888xvenous pH+0.150xPCO2+0.812xvenous HCO3+0.124xvenous total CO2 (R2=0.609), arterial HCO3=-89.266+12.677xvenous pH+0.042xPCO2+0.675xvenous HCO3+0.185xvenous total CO2 (R2=0.782). The mean ABG minus peripheral VBG differences for pH, PCO2, and bicarbonates were not clinically important for between-person heterogeneity. CONCLUSION: Peripheral venous pH, PCO2, bicarbonates, and total CO2 may be used as alternatives to their arterial equivalents in many clinical contexts encountered in the ICU.

Correlation between peripheral venous and arterial blood gas measurements in patients admitted to the intensive care unit: A single-center study

BACKGROUND: The objective of this study was to examine the correlation between arterial blood gas (ABG) and peripheral venous blood gas (VBG) samples for all commonly used parameters in patients admitted to a medical intensive care unit (ICU). METHODS: A single-center, prospective trial was carried out in a medical ICU in order to determine the level of correlation of ABG and peripheral VBG measurements. A maximum of five paired ABG-VBG samples were obtained per patient to prevent a single patient from dominating the data set. RESULTS: Regression equations were derived to predict arterial values from venous values as follows: arterial pH=-1.108+1.145xvenous pH+0.008xPCO2-0.012xvenous HCO3+0.002xvenous total CO2 (R2=0.655), arterial PCO2=88.6-10.888xvenous pH+0.150xPCO2+0.812xvenous HCO3+0.124xvenous total CO2 (R2=0.609), arterial HCO3=-89.266+12.677xvenous pH+0.042xPCO2+0.675xvenous HCO3+0.185xvenous total CO2 (R2=0.782). The mean ABG minus peripheral VBG differences for pH, PCO2, and bicarbonates were not clinically important for between-person heterogeneity. CONCLUSION: Peripheral venous pH, PCO2, bicarbonates, and total CO2 may be used as alternatives to their arterial equivalents in many clinical contexts encountered in the ICU.

Seizure or Syncope: The Usefulness of Serum Laboratory Tests and Arterial Blood Gas Analysis for Making the Differential Diagnosis

PURPOSE: To determine whether analyte levels in serum laboratory tests and arterial blood gas analysis (ABGA) are helpful for differentiating between generalized seizures and syncope in the emergency department (ED). METHODS: Patients over 18 years old who presented to an ED of a tertiary care hospital with a transient loss of consciousness within 4 hours were selected to be in either the seizure (n=166) or syncope groups (n=168). After exclusion for criteria, we used ROC curves to determine AUC, optimal cut-off value, sensitivity, and specificity, depending on time (4 hour, 2 hour, 1 hour and 0.5 hour). We also did multivariate logistic regression. RESULTS: A total of 75 seizure group patients and 78 syncope group patients were studied. There were significant between group differences in total CO2 content, LDH, ammonia, pH, bicarbonate and lactate. AUC (area under the curve) values for blood tests were: 0.720 (tCO2), 0.686 (LDH), 0.737 (ammonia), 0.798 (pH), 0.710 (bicarbonate) and 0.770 (lactate). All AUC values were increased as the time from symptoms to ED arrival was shortened (except for LDH). On multivariate logistic regression analysis, pH (OR=9.587, 95% CI, 2.573-35.723. p=0.001) and ammonia (OR=3.932, 95% CI, 1.324-11.613, p=0.014) were statistically significant independent predictive factors. CONCLUSION: Serum laboratory testing and ABGA, especially serum ammonia and arterial pH, may be helpful for differentiating between generalized seizure and syncope in patients who experience a transient loss of consciousness and who come to the ED within 4 hours after the appearance of symptoms. But further evaluation is needed.

A case of severe metabolic acidosis after orthotopic neobladder replacement / 대한내과학회지

Following a radical cystectomy to treat bladder cancer, the ureters can be implanted in a short loop of ileum, which serves as an orthotopic bladder replacement. However, several investigators have reported the frequent development of a normal anion gap metabolic acidosis and electrolyte disturbance in these patients. The colon segments secrete sodium and bicarbonate ions and reabsorb ammonium, hydrogen, and chloride ions when exposed to urine, causing metabolic acidosis. In most cases, the acid-base disorder is not very troublesome. The metabolic acidosis can usually be corrected by administering sodium bicarbonate. We experienced a case of severe metabolic acidosis associated with urinary diversion that improved with continuous renal replacement therapy (CRRT).

Effect of Treatment in Patient with Rhabdomyolysis: Comparison between Single Hydration and Hydration with Urine Alkalinization

PURPOSE: Urine alkalinization is commonly used to treat rhabdomyolysis and to prevent the rapid progression of rhabdomyolysis into acute renal failure. However, there are no prospective studies on the beneficial effect of urine alkalinization on rhabdomyolysis. We prospectively examined whether fluid hydration with urine alkalinization treatment would be more effective than single hydration treatment in treating rhabdomyolysis and preventing acute renal failure in the emergency department. METHODS: We performed a prospective randomized trial with fifty-eight patients who were diagnosed with rhabdomyolysis. Thirty-five patients were treated with crystalloid alone, while the others were treated with crystalloid mixed with sodium bicarbonates. Creatine phosphokinase (CPK) and creatinine levels were checked every 4 hours for the first 24 hours and then checked every 8 hours thereafter. Data collected included "peak CPK time"(time from the start of treatment to achievement of the maximal CPK value), increasing and decreasing rate of CPK, and whether acute renal failure developed. RESULTS: Patient's age, sex, initial CPK concentrations, and initial creatinine concentrations were not statistically different between the single hydration treatment group and the hydration with urine alkalinization group. Mean time to peak CPK was 10.2+/-13.7 hours in the single hydration group and 8.1+/-10.2 hours in the hydration with urine alkalinization group. Neither the time to peak CPK nor the CPK change rates was statistically different between the two groups (p=0.547, p=0.176, p=0.696). CONCLUSION: Hydration with urine alkalinization as a treatment for rhabdomyolysis and prevention of acute renal failure did not improve patient results over single hydration treatment.

Significance of infusion of sodium bicarbonate in amniotic cavity under continuous internal fetal heart rate monitoring for management of fetal distress during labor / 中华妇产科杂志

Objective To investigate the effect of infusion of sodium bicarbonate in amniotic cavity and exchange of amniotic fluid for fetus with distress and acidosis. Methods The patients included 40 cases of oligohydramnios with mild and serious abnormality of fetal heart rate and amniotic fluid contamination of degree Ⅱ or more during the labor. The 40 cases had exchange of amniotic fluid with infusion under continuous monitoring. Twenty of them had infusion with 5% sodium bicarbonate into amniotic cavity; the other 20 cases received 5% sodium bicarbonate intravenous in fusion. After the labor all the patients had test of arterial blood gas in umbilical cord and the fetuses were evaluated with Apgar score. Results (1)the effective rate was 88% in the group of infusion into amniotic cavity and 85% in the group of exchange of amniotic fluid. (2)The arterial blood pH, PO_2, HCO~-_3, ABE, SBE in the group of amniotic cavity infusion with 5% sodium bicarbonate were all higher than group of Ⅳinfusion, however PCO_2 was significantly lower than the group of Ⅳ(P