Factors Influencing Blood Alkalosis and Other Physiological Responses, Gastrointestinal Symptoms, and Exercise Performance Following Sodium Citrate Supplementation: A Review.

This review aimed to identify factors associated with (a) physiological responses, (b) gastrointestinal (GI) symptoms, and (c) exercise performance following sodium citrate supplementation. A literature search identified 33 articles. Observations of physiological responses and GI symptoms were categorized by dose (< 500, 500, and > 500 mg/kg body mass [BM]) and by timing of postingestion measurements (in minutes). Exercise performance following sodium citrate supplementation was compared with placebo using statistical significance, percentage change, and effect size. Performance observations were categorized by exercise duration (very short < 60 s, short ≥ 60 and ≤ 420 s, and longer > 420 s) and intensity (very high > 100% VO2max and high 90-100% VO2max). Ingestion of 500 mg/kg BM sodium citrate induced blood alkalosis more frequently than < 500 mg/kg BM, and with similar frequency to >500 mg/kg BM. The GI symptoms were minimized when a 500 mg/kg BM dose was ingested in capsules rather than in solution. Significant improvements in performance following sodium citrate supplementation were reported in all observations of short-duration and very high-intensity exercise with a 500 mg/kg BM dose. However, the efficacy of supplementation for short-duration, high-intensity exercise is less clear, given that only 25% of observations reported significant improvements in performance following sodium citrate supplementation. Based on the current literature, the authors recommend ingestion of 500 mg/kg BM sodium citrate in capsules to induce alkalosis and minimize GI symptoms. Supplementation was of most benefit to performance of short-duration exercise of very high intensity; further investigation is required to determine the importance of ingestion duration and timing.

Trombocitopenia por agregados plaquetarios / Thrombocytopenia by aggregated platelet: case report

Introducción: la pseudotrombocitopenia inducida por EDTA (ácido etilendiamino tetraacético) es un fenómeno de aglutinación de plaquetas que se presenta in vitro, mediado por anticuerpos anti-plaquetarios de tipo IgG, IgA o IgM dirigidos contra el complejo glucoproteínico IIb/IIIa de la membrana plaquetaria. Caso clínico: presentamos un caso clínico de una paciente de 59 años de edad sometida a recambio valvular aórtico; clínicamente con evolución favorable durante el periodo posquirúrgico, sin embargo, en estudios de control se registra trombocitopenia severa, lo que llevo a cuestionar el uso de anticoagulantes y la necesidad de transfusión de plaquetas. Al realizar estudios complementarios se encontró agregados plaquetarios en el frotis de sangre periférica, posteriormente se realizó recuento seriado de plaquetas y comparación del histograma plaquetario, catalogando el caso como pseudotrombocitopenia. Conclusión: La trombocitopenia por agregados plaquetarios es una condición de baja incidencia (0.07% a 0.1%). Se debe a la agregación de plaquetas in vitro asociada al uso de anticoagulantes, frecuentemente etilendiaminotetraacético (EDTA), en el presente caso también se asoció al uso de citrato de sodio. Este problema no se asocia a sangrado, sin embargo su desconocimiento pudo haber llevado a realizar procedimientos diagnósticos y terapéuticos innecesarios

Introduction: EDTA (ethylenediamine tetraacetic acid) ­induced by pseudothrombocytopenia is a platelet agglutination phenomenon that occurs in vitro, which are mediated by anti-platelet antibodies of the IgG, IgA or IgM type directed against the glycoprotein complex IIb / IIIa of the platelet membrane . Clinical case: This is a clinical case of a 59-yearsold patient undergoing aortic valve replacement, clinically with a favorable evolution during the postoperative period, however, in control studies, severe thrombocytopenia was recorded, which led to questioning the use of anticoagulants and the need for platelet transfusion. When carrying out complementary studies, aggregated platelet were found in the peripheral blood smear, later, a serial platelet count and comparison of the platelet histogram were performed, classifying the case as pseudotrombocytopenia. Conclusion: Thrombocytopenia due to aggregated platelet is a low incidence condition (0.07% to 0.1%). It is due to the aggregation of platelets in vitro associated with the use of anticoagulants [frequently ethylenediamine tetra acetic (EDTA)]; in the present case it was also associated with the use of sodium citrate. This problem is not associated with bleeding; however its lack of knowledge leads to unnecessary diagnostic and therapeutic procedures.

A randomized controlled clinical trial of 4% sodium citrate versus heparin as locking solution for temporary dialysis catheters among hemodialysis patients
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BACKGROUND: Limited reports are available on the role of 4% citrate as a locking solution for temporary dialysis catheters. Hence, the aim of this study is to investigate the role of 4% citrate vs. heparin 5,000 µ/mL as a catheter-locking solution in a randomized controlled trial. MATERIALS AND METHODS: The trial was conducted in Egypt where the use of non-tunneled temporary catheters is prevalent compared to tunneled long-term catheters. The efficacy of catheter-locking solutions was compared regarding observation of rate of catheter dysfunction, low-flow pump, fever as a sign of central-line blood-stream infection (CLBSI), catheter-site infection, thrombosis, local bleeding, and systemic bleeding in each group of the study. RESULTS: Each group consisted of 105 patients. The number of patients who developed CLBSI in the citrate group was 11 (10.5%) compared to 23 (21.9%) in the heparin group (p < 0.025). The number of patients who developed catheter dysfunction in the citrate group was similar to those in the heparin group. The incidence of catheter-site infection, thrombosis, and local bleeding in the citrate group was similar to that in the heparin group. CONCLUSION: Citrate 4% lock solution is equally effective as heparin in maintaining catheter patency in dialysis patients. It may have a favorable effect on prevention of catheter-related infection due to its additional antiseptic properties as compared to heparin. Citrate-based locking solutions are a promising alternative to unfractionated heparin as a locking solution for dialysis catheters.
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Lithium increases ammonium excretion leading to altered urinary acid-base buffer composition.

Previous reports identify a voltage dependent distal renal tubular acidosis (dRTA) secondary to lithium (Li+) salt administration. This was based on the inability of Li+-treated patients to increase the urine-blood (U-B) pCO2 when challenged with NaHCO3 and, the ability of sodium neutral phosphate or Na2SO4 administration to restore U-B pCO2 in experimental animal models. The underlying mechanisms for the Li+-induced dRTA are still unknown. To address this point, a 7 days time course of the urinary acid-base parameters was investigated in rats challenged with LiCl, LiCitrate, NaCl, or NaCitrate. LiCl induced the largest polyuria and a mild metabolic acidosis. Li+-treatment induced a biphasic response. In the first 2 days, proper urine volume and acidification occurred, while from the 3rd day of treatment, polyuria developed progressively. In this latter phase, the LiCl-treated group progressively excreted more NH4+ and less pCO2, suggesting that NH3/NH4+ became the main urinary buffer. This physiological parameter was corroborated by the upregulation of NBCn1 (a marker of increased ammonium recycling) in the inner stripe of outer medulla of LiCl treated rats. Finally, by investigating NH4+ excretion in ENaC-cKO mice, a model resistant to Li+-induced polyuria, a primary role of the CD was confirmed. By definition, dRTA is characterized by deficient urinary ammonium excretion. Our data question the presence of a voltage-dependent Li+-induced dRTA in rats treated with LiCl for 7 days and the data suggest that the alkaline urine pH induced by NH3/NH4+ as the main buffer has lead to the interpretation dRTA in previous studies.

Regional citrate anticoagulation in membrane based plasma exchange: Safety, efficacy and effect on calcium balance.

AIM: To assess the efficacy, safety and calcium balance of a membrane based regional citrate anticoagulation plasma exchange protocol. METHODS: This was an observational, prospective, single centre study of membrane separation plasma exchange using regional citrate anticoagulation. It was performed using a fixed dose pre-filter citrate infusion that was based on the plasma flow rate. Patients received a post filter calcium infusion that was modified during treatment based on systemic ionized calcium monitoring. Post filter ionized calcium was not assessed. Safety and efficacy were assessed by extraction of clinical events and laboratory data contemporaneously recorded in electronic health records. RESULTS: Thirty-six sessions in five patients were performed. No patients developed symptomatic hypocalcaemia, and no patient had a recorded ionized calcium below 0.81 mmol/L. Filter clotting occurred in two sessions. The mean net calcium gained was 9.6 ± 1.8 mmol per session. CONCLUSION: Regional citrate anticoagulated membrane separation plasma exchange can be performed safely and effectively without the need for post filter ionized calcium monitoring. The algorithm employed resulted in a net calcium gain.