Objective To evaluate the associations between the serum anion gap （AG） with the severity and prognosis of coronary artery disease （CAD）. Methods We measured serum electrolytes in 18,115 CAD patients indicated by ...Objective To evaluate the associations between the serum anion gap （AG） with the severity and prognosis of coronary artery disease （CAD）. Methods We measured serum electrolytes in 18,115 CAD patients indicated by coronary angiography. The serum AG was calculated according to the equation： AG = Na^＋ [（mmol/L） ＋ K^＋ （mmol/L）] - [Cl^- （mmol/L） ＋ HCO3^- （mmol/L）]. Results A total of 4510 （24.9%） participants had their AG levels greater than 16 mmol/L. The serum AG was independently associated with measures of CAD severity, including more severe clinical types of CAD （P 〈 0.001） and worse cardiac function （P = 0.004）. Patients in the 4th quartile of serum AG （≥ 15.92 mmol/L） had a 5.171-fold increased risk of 30 days all-cause death （P 〈 0.001）. This association was robust, even after adjustment for age, sex, evaluated glomerular filtration rate [hazard ratio （HR）： 4.861, 95% confidence interval （CI）： 2.150–10.993, P 〈 0.001], clinical diagnosis, severity of coronary artery stenosis, cardiac function grades, and other confounders （HR： 3.318, 95% CI： 1.76–2.27, P = 0.009）. Conclusion In this large population-based study, our findings reveal a high percentage of increased serum AG in CAD. Higher AG is associated with more severe clinical types of CAD and worse cardiac function. Furthermore, the increased serum AG is an independent, significant, and strong predictor of all-cause mortality. These findings support a role for the serum AG in the risk-stratification of CAD.展开更多
The Stewart approach-the application of basic physicalchemical principles of aqueous solutions to blood-is an appealing method for analyzing acid-base disorders. These principles mainly dictate that p H is determined ...The Stewart approach-the application of basic physicalchemical principles of aqueous solutions to blood-is an appealing method for analyzing acid-base disorders. These principles mainly dictate that p H is determined by three independent variables, which change primarily and independently of one other. In blood plasma in vivo these variables are:(1) the PCO2;(2) the strong ion difference(SID)-the difference between the sums of all the strong(i.e., fully dissociated, chemically nonreacting) cations and all the strong anions; and(3) the nonvolatile weak acids(Atot). Accordingly, the p H and the bicarbonate levels(dependent variables) are only altered when one or more of the independent variables change. Moreover, the source of H+ is the dissociation of water to maintain electroneutrality when the independent variables are modified. The basic principles of the Stewart approach in blood, however, have been challenged in different ways. First, the presumed independent variables are actually interdependent as occurs in situations such as:(1) the Hamburger effect(a chloride shift when CO2 is added to venous blood from the tissues);(2) the loss of Donnan equilibrium(a chloride shift from the interstitium to the intravascular compartment to balance the decrease of Atot secondary to capillary leak; and(3) the compensatory response to a primary disturbance in either independent variable. Second, the concept of water dissociation in response to changes in SID is controversial and lacks experimental evidence. In addition, the Stewart approach is not better than the conventional method for understanding acid-base disorders such as hyperchloremic metabolic acidosis secondary to a chloride-rich-fluid load. Finally, several attempts were performed to demonstrate the clinical superiority of the Stewart approach. These studies, however, have severe methodological drawbacks. In contrast, the largest study on this issue indicated the interchangeability of the Stewart and conventional methods. Although the introduction of the Stewart 展开更多
Diabetes mellitus is the most common metabolic disorder occasioned by derangement in glucose equilibration between the ECF and ICF. The derangement is known to affect the appropriate balance of electrolytes that serve...Diabetes mellitus is the most common metabolic disorder occasioned by derangement in glucose equilibration between the ECF and ICF. The derangement is known to affect the appropriate balance of electrolytes that serves as a buffer in the body. In this study anion gap was evaluated among outpatient diabetics as compared to non-diabetics control group. The categorization into the study or control groups was done by serum glucose estimation using glucose oxidase method. The study group mean age was 51 ±14 as against control group of 47 ± 10. One hundred and fifty subjects were divided in two groups based on serum glucose concentration. Group A (control group) consisted of 50 subjects with mean serum glucose concentration 4.3 ±1.7 mmol/l and anion gap 13.8 ± 2.6, group B (diabetics) consisted of 100 subjects that had serum glucose concentration 15.0 ± 3.9 and anion gap 18.4 ± 2.5. The glucose was estimation by glucose oxidase method, whereas the anion gap was calculated by subtracting the concentrations of sodium and potassium from the concentrations of chloride and bicarbonate. The concentrations of the electrolytes where assayed using ion selective electrodes (ISE). A statistical significant difference P was observed between group A and B glucose concentrations and the anion gap. The abnormal anion gap was created by the insufficiency of bicarbonate used for the buffering of the electrolytes variability occasioned by derangement in glucose metabolism and distorted hormonal secretion. Hence metabolic acidosis is strongly linked with diabetics as a result of distorted anion gap. Healthcare providers and takers should ensure that anion gap estimation is factored into investigations for the management of diabetics. Also, patients with deranged anion gap should be placed as an emergency case for proper management. Clinicians should ensure that patient’s anion gap is within the reference anion gap range so as to prevent development into metabolic acidosis and subsequent ketoacidosis.展开更多
Objective: The traditional approach for acid base interpretation is based on Handerson-Hasselbalch formula and includes Base Excess (BE), bicarbonate (HCO3), albumin corrected anion gap. The Physicochemical approach i...Objective: The traditional approach for acid base interpretation is based on Handerson-Hasselbalch formula and includes Base Excess (BE), bicarbonate (HCO3), albumin corrected anion gap. The Physicochemical approach is centered on the Carbon Dioxide tension (PCO2), the strong ion difference (SID), strong ion gap (SIG) = SID apparent-SID effective and totally weak acids (Atot). The study aims to compare between the traditional approach and the physicochemical approach in acid base disorder interpretation. Design: Prospective observational study in an adult Intensive Care Unit (ICU) recruiting six hundred and sixty one patients. Methods: Arterial blood samples were analyzed to measure pH, PaCO2 sodium, potassium, chloride and lactate. Venous blood samples were analyzed to measure ionized calcium, magnesium, phosphorous and albumin. These samples were interpreted by both techniques. Results: Normal HCO3 and BE were detected by traditional approach in 49 cases of which SIG acidosis was detected in 22 cases (46%) and Hyperchloremic acidosis was detected in 29 cases (60%) by physicochemical method. SIG was elevated in 72 cases (58%) of 124 cases with high anion gap acidosis. SIDeff and BE were strongly correlated, r = 0.8, p 0.0001, while SIG and Albumin corrected Anion Gap (ALAG) were moderately correlated r = 0.56, p Conclusion: Both approaches are important for interpretation of the acid base status. Traditional approach identifies the diagnostic description without many calculations and detects body compensatory response to acid base disorders. Physicochemical approach is essential to identify the exact causation and the severity of the acid base disorders.展开更多
基金Acknowledgement This work was supported by the Beijing Nova Program （No. Z121107002512053）, the Beijing Health System High Level Health Technology Talent Cultivation Plan （No. 2013-3-013）, the Beijing Outstanding Talent Training Program （No. 2014000021223ZK32）, and the National Natural Science Foundation of China （No. 81100143） to S.W.Y., and the Beijing Municipal Administration of Hospitals Clinical Medicine Development of Special Funding Support （No. ZYLX201303） to Y.J.Z.
文摘Objective To evaluate the associations between the serum anion gap （AG） with the severity and prognosis of coronary artery disease （CAD）. Methods We measured serum electrolytes in 18,115 CAD patients indicated by coronary angiography. The serum AG was calculated according to the equation： AG = Na^＋ [（mmol/L） ＋ K^＋ （mmol/L）] - [Cl^- （mmol/L） ＋ HCO3^- （mmol/L）]. Results A total of 4510 （24.9%） participants had their AG levels greater than 16 mmol/L. The serum AG was independently associated with measures of CAD severity, including more severe clinical types of CAD （P 〈 0.001） and worse cardiac function （P = 0.004）. Patients in the 4th quartile of serum AG （≥ 15.92 mmol/L） had a 5.171-fold increased risk of 30 days all-cause death （P 〈 0.001）. This association was robust, even after adjustment for age, sex, evaluated glomerular filtration rate [hazard ratio （HR）： 4.861, 95% confidence interval （CI）： 2.150–10.993, P 〈 0.001], clinical diagnosis, severity of coronary artery stenosis, cardiac function grades, and other confounders （HR： 3.318, 95% CI： 1.76–2.27, P = 0.009）. Conclusion In this large population-based study, our findings reveal a high percentage of increased serum AG in CAD. Higher AG is associated with more severe clinical types of CAD and worse cardiac function. Furthermore, the increased serum AG is an independent, significant, and strong predictor of all-cause mortality. These findings support a role for the serum AG in the risk-stratification of CAD.
文摘The Stewart approach-the application of basic physicalchemical principles of aqueous solutions to blood-is an appealing method for analyzing acid-base disorders. These principles mainly dictate that p H is determined by three independent variables, which change primarily and independently of one other. In blood plasma in vivo these variables are:(1) the PCO2;(2) the strong ion difference(SID)-the difference between the sums of all the strong(i.e., fully dissociated, chemically nonreacting) cations and all the strong anions; and(3) the nonvolatile weak acids(Atot). Accordingly, the p H and the bicarbonate levels(dependent variables) are only altered when one or more of the independent variables change. Moreover, the source of H+ is the dissociation of water to maintain electroneutrality when the independent variables are modified. The basic principles of the Stewart approach in blood, however, have been challenged in different ways. First, the presumed independent variables are actually interdependent as occurs in situations such as:(1) the Hamburger effect(a chloride shift when CO2 is added to venous blood from the tissues);(2) the loss of Donnan equilibrium(a chloride shift from the interstitium to the intravascular compartment to balance the decrease of Atot secondary to capillary leak; and(3) the compensatory response to a primary disturbance in either independent variable. Second, the concept of water dissociation in response to changes in SID is controversial and lacks experimental evidence. In addition, the Stewart approach is not better than the conventional method for understanding acid-base disorders such as hyperchloremic metabolic acidosis secondary to a chloride-rich-fluid load. Finally, several attempts were performed to demonstrate the clinical superiority of the Stewart approach. These studies, however, have severe methodological drawbacks. In contrast, the largest study on this issue indicated the interchangeability of the Stewart and conventional methods. Although the introduction of the Stewart
文摘Diabetes mellitus is the most common metabolic disorder occasioned by derangement in glucose equilibration between the ECF and ICF. The derangement is known to affect the appropriate balance of electrolytes that serves as a buffer in the body. In this study anion gap was evaluated among outpatient diabetics as compared to non-diabetics control group. The categorization into the study or control groups was done by serum glucose estimation using glucose oxidase method. The study group mean age was 51 ±14 as against control group of 47 ± 10. One hundred and fifty subjects were divided in two groups based on serum glucose concentration. Group A (control group) consisted of 50 subjects with mean serum glucose concentration 4.3 ±1.7 mmol/l and anion gap 13.8 ± 2.6, group B (diabetics) consisted of 100 subjects that had serum glucose concentration 15.0 ± 3.9 and anion gap 18.4 ± 2.5. The glucose was estimation by glucose oxidase method, whereas the anion gap was calculated by subtracting the concentrations of sodium and potassium from the concentrations of chloride and bicarbonate. The concentrations of the electrolytes where assayed using ion selective electrodes (ISE). A statistical significant difference P was observed between group A and B glucose concentrations and the anion gap. The abnormal anion gap was created by the insufficiency of bicarbonate used for the buffering of the electrolytes variability occasioned by derangement in glucose metabolism and distorted hormonal secretion. Hence metabolic acidosis is strongly linked with diabetics as a result of distorted anion gap. Healthcare providers and takers should ensure that anion gap estimation is factored into investigations for the management of diabetics. Also, patients with deranged anion gap should be placed as an emergency case for proper management. Clinicians should ensure that patient’s anion gap is within the reference anion gap range so as to prevent development into metabolic acidosis and subsequent ketoacidosis.
文摘Objective: The traditional approach for acid base interpretation is based on Handerson-Hasselbalch formula and includes Base Excess (BE), bicarbonate (HCO3), albumin corrected anion gap. The Physicochemical approach is centered on the Carbon Dioxide tension (PCO2), the strong ion difference (SID), strong ion gap (SIG) = SID apparent-SID effective and totally weak acids (Atot). The study aims to compare between the traditional approach and the physicochemical approach in acid base disorder interpretation. Design: Prospective observational study in an adult Intensive Care Unit (ICU) recruiting six hundred and sixty one patients. Methods: Arterial blood samples were analyzed to measure pH, PaCO2 sodium, potassium, chloride and lactate. Venous blood samples were analyzed to measure ionized calcium, magnesium, phosphorous and albumin. These samples were interpreted by both techniques. Results: Normal HCO3 and BE were detected by traditional approach in 49 cases of which SIG acidosis was detected in 22 cases (46%) and Hyperchloremic acidosis was detected in 29 cases (60%) by physicochemical method. SIG was elevated in 72 cases (58%) of 124 cases with high anion gap acidosis. SIDeff and BE were strongly correlated, r = 0.8, p 0.0001, while SIG and Albumin corrected Anion Gap (ALAG) were moderately correlated r = 0.56, p Conclusion: Both approaches are important for interpretation of the acid base status. Traditional approach identifies the diagnostic description without many calculations and detects body compensatory response to acid base disorders. Physicochemical approach is essential to identify the exact causation and the severity of the acid base disorders.
