Simplified Regional Citrate Anticoagulation Using a Calcium-Containing Replacement Solution for Continuous Renal Replacement Therapy: A Randomized Controlled Trial

Introduction A simplified protocol for regional citrate anticoagulation (RCA) using a commercial calcium-containing replacement solution, without continuous calcium infusion, is more efficient to be used in continuous renal replacement therapy (CRRT). We aim to design a randomized clinical trial (RCT) to compare the safety and efficacy between calcium-free and calcium-containing replacement solution in CRRT with RCA. Methods Of the 64 patients receiving RCA-based post-dilution continuous venovenous hemodiafiltration (CVVHDF) enrolled from 2017-2019, 35 patients were randomized to calcium-containing group and 29 to calcium-free replacement solution group. Primary endpoint was circuit lifespan. Secondary endpoints included mortality, kidney function recovery and complications. The amount of 4% trisodium citrate solution infusion was recorded. Serum and effluent total and ionized calcium concentration were measured during CVVHDF. Results Total 149 circuits (82 in calcium-containing group and 67 in calcium-free group) and 7609 circuit hours (4335 versus 3274 hours) were included. Mean circuit lifespan was 58.1 hours (95% CI 53.8-62.4) in calcium-containing group versus 55.3 hours (95% CI 49.7-60.9, log rank P=0.89) in calcium-free group. The serum total (tCa) and ionized (iCa) calcium concentration was slightly lower in calcium-containing group during CRRT, whereas the post-filter iCa concentration was lower in calcium-free group. Moreover, mean 4% trisodium citrate solution infusion doses had no difference between groups (171.1±15.9 versus 169.0±15.1 ml/h, P=0.49). The mortality (40.0% versus 44.8%, P=0.70) and kidney function recovery rates (54.3% versus 48.3%, P=0.63) were similar in calcium-containing and calcium-free group during hospitalization, respectively. Six (3 in each group) patients showed the signs of citrate accumulation in this study. Conclusions When compared with calcium-free replacement solution, RCA based CVVHDF with calcium-containing replacement solution had similar circuit lifespan, hospital mortality and kidney outcome. Since the calcium-containing solution obviates the need for a separate venous catheter and large dose of intravenous calcium solution preparation for continuous calcium supplement, it is more convenient to be applied in RCA-CRRT practice.Trial registration Chinese Clinical Trial Registry. ChiCTR-IPR-17012629, registered on 10th September 2017. http://www.chictr.org.cn/showprojen.aspx?proj=17644

Analytical solutions of citrate–phosphate coupled model of rice (Oryza sativa L.) roots

The citrate secreted by the rice (Oryza sativa L.) roots will promote the absorption of phosphate, and this process is described by the Kirk model. In our work, the Kirk model is divided into citrate sub-model and phosphate sub-model. In the citrate sub-model, we obtain the analytical solution of citrate with the Laplace transform, inverse Laplace transform and convolution theorem. The citrate solution is substituted into the phosphate sub-model, and the analytical solution of phosphate is obtained by the separation variable method. The existence of the solutions can be proved by the comparison test, the Weierstrass M-test and the Abel discriminating method.

P1074SIMPLIED REGIONAL CITRATE ANTICOULATION USING A CALCIUM-CONTAINING REPLACEMENT SOLUTION FOR RENAL REPLACEMENT THERAPY: A RANDOMIZED CONTROLLED CLINICAL TRIAL

Background and Aims A simplified protocol for Regional citrate anticoagulation (RCA) using a commercial calcium-containing replacement solution, without a continuous calcium infusion, is more efficient to be used in continuous renal replacement therapy (CRRT). We aim to design a randomized prospective pilot trial to compare the safety and efficacy between calcium-free and calcium-containing replacement solution in CRRT with RCA. Method Of the 59 patients who requiring CRRT and being treated with RCA-based continuous venovenous hemodiafiltration (CVVHDF) enrolled, 31 patients were randomized to calcium-containing group and 28 to calcium-free replacement solution group. Primary endpoints were filters lifespan. Secondary endpoints were mortality, kidney function recovery and severe complications rates. Time spent on fluids preparation before CRRT and the amount of 4% trisodium citrate solution pumped during CRRT were recorded. Serum and effluent citrate and calcium concentration during CVVHDF were measured during CRRT. Results Filters lifespan were superior for calcium-containing group (mean 58.06 versus 47.12 hours, P=0.05). Mortality and renal outcome were comparable between groups during hospitalization: 10/31 (33.26%) of calcium-containing group patients died versus 13/28 (46.43%) of calcium-free group patients, and 16/31 (51.61%) of calcium-containing group patients had kidney function recovery versus 15/28 (53.57%) of calcium-containing group (P = 0.265). Only 5 patients showed the symptoms and signs of hypocalcemia or citrate toxicity in this study. The mean CRRT preparation time in calcium-containing group: 25.5 minutes, was significantly shorter than calcium-free group: 43.7 minutes (p<0.001). The serum and effluent calcium concentration was slightly lower in calcium-containing group during CRRT. While, the mean 4% trisodium citrate solution infusion rate was similar between groups (161.5 mL/h versus 157.4 mL/h, P=0.376). Conclusion Patients treated with calcium-containing or calcium-free replacement solution have similar clinical outcomes. Since the calcium-containing replacement solution based RCA has longer filter lifespan and obviates the need for a separate venous catheter and intravenous calcium preparation for continuous intravenous calcium infusion, it is more efficient to be used in clinical practice and superior to the calcium-free replacement solution.

P1096SAFETY AND EFFICACY OF A NEW SIMPLIFIED REGIONAL CITRATE ANTICOAGULATION PROTOCOL FOR SUSTAINED LOW EFFICIENCY DIALYSIS FOCUSED ON PREVENTION OF RRT-INDUCED HYPOPHOSPHATEMIA IN CRITICALLY ILL RENAL PATIENTS

Background and Aims Sustained-Low Efficiency Dialysis (SLED) is a hybrid Renal Replacement Therapy (RRT) increasingly used in critically ill patients with Acute Kidney Injury (AKI). Usually lasting 8-12 hours, this modality combines several advantages of both intermittent and continuous RRT (CRRT). Regional citrate anticoagulation (RCA) represents the most adequate anticoagulation strategy to avoid the extracorporeal circuit clotting. Hypophosphatemia (serum phosphorus, s-P, levels ≤ 2.5 mg/dl) is a common electrolyte disorder in critically ills, with an increased incidence in course of prolonged RRTs, especially when standard dialysis/replacement solutions and highly intensive modalities are employed. Given the potentially negative impact of hypophosphatemia on patients’ outcomes, strategies aimed at preventing its onset should be appropriately implemented. This pilot study is aimed at evaluation of safety and efficacy of a simplified RCA protocol for SLED, based on the combination of a low-concentrated citrate solution with a phosphate-containing solution. Methods a prospective observational study was conducted on critically ill patients with AKI requiring RRT or End Stage Renal Disease (ESRD) previously on RRT admitted to our renal Intensive Care Unit (ICU). SLED was performed by the Prismax system (Baxter) and polyacrylonitrile AN69 haemofilters (ST 150, 1.5 m2, Baxter). 8-hours SLED sessions were prescribed, in the SLED-f variant, by using a 18 mmol/l pre-dilution trisodium citrate solution (Regiocit 18/0, Baxter) combined with a phosphate-containing solution acting as dialysate (Ca2+ 0, HPO42- 1, Mg2+ 0.75, HCO3- 22 mmol/l; Biphozyl, Baxter) and a standard RRT solution acting as post-dilution replacement fluid (Prismasol 4, Baxter). Calcium chloride (CaCl 10%) was infused in a separate central venous line to maintain the systemic Ca2+ (s-Ca2+) within a normal range. Each patient underwent three consecutive daily SLED sessions. The activated coagulation time (ACT), acid–base parameters, s-Ca2+ and potassium were measured at SLED start and every 2 h. Phosphorus and magnesium losses with RRT were replaced, when needed, with sodium glycerophosphate pentahydrate (GlycophosTM 20 mmol/20 ml, Fresenius Kabi Norge AS, Halden, Norvegia) and magnesium sulphate. Results a total of 60 SLED-f sessions were performed in 20 ICU patients. At ICU admission, the average APACHE II score was 21.8 and half of patients were mechanically ventilated. Many of them showed hemodynamic instability and AKI was oliguric in 90% of cases. No premature interruptions for irreversible filter clotting occurred and the prescribed dialysis dose was delivered in 95% of cases. No statistically significant differences were observed between systemic ACT at SLED start and during RRT sessions, and no major hemorrhagic events were observed. Regarding RCA, no clinically relevant episode of hypo or hypercalcemia was observed, and calcium infusion rate remained constant in course of treatments. Acid-base status was effectively maintained during the entire period of treatment and no episodes of clinically relevant metabolic acidosis or alkalosis were registered. The analysis of the main laboratory variables at SLED start, in course and after 24 h of treatment did not show statistically significant differences. Regardless of starting values, s-P and s-Mg were progressively corrected and maintained within the normality range, limiting the need for exogenous supplementations. Conclusions These preliminary data suggest that our simplified RCA protocol for SLED, combining a low-citrate solution with a phosphate-containing solution, is safe and efficacious allowing to optimizing acid-base balance and to preventing RRT-related hypophosphatemia.

Kandungan Fe, Al, dan Si Bebas dan Status Kesuburan Tanah pada Entisol dan Inceptisol di Lahan Kering Jantho, Kabupaten Aceh Besar

Abstrak. Fe, Al, dan Si bebas di dalam tanah umumnya terdapat sebagai bentuk mineral yang merupakan komposisi utama tanah pada lahan kering di wilayah tropika basah. Kandungan unsur tersebut di dalam tanah dapat diekstrak dengan larutan dithionite-sitrat. Penelitian ini bertujuan untuk mengetahui kandungan dan distribusi Fe, Al, dan Si-bebas tanah pada setiap lapisan horizon tanah ordo Entisol dari Desa Jalin dan Inceptisol dari Desa Cucum dan Buket Meusara serta status kesuburan tanahnya di lahan kering Jantho Kabupaten Aceh Besar. Analisis Fe, Al, dan Si-bebas diekstrak dengan larutan 0,1 N Natrium dithionit-sitrat (Holmgren, 1976) dan diukur konsentrasinya dengan Spektrofotometer Serapan Atom (SAA). Hasil Penelitian menunjukkan bahwa kandungan Fe-bebas tanah pada ketiga ordo tanah tergolong rendah (0,01-1,43%) sedangkan Al-bebas tanah bervariasi antar ordo tanah dan berkisar dari rendah hingga tinggi (1,60-11,72%). Kandungan Si-bebas pada ketiga ordo tanah di lahan kering Jantho juga bervariasi dari rendah sampai tinggi (1,48-13,05%). Kandungan Fe-bebas terendah dijumpai pada Inceptisol Cucum, sementara Al- dan Si-bebas terendah dijumpai pada Inceptisol Buket Meusara. Berdasarkan komposisi Fe, Al, dan Si, maka ketiga ordo tanah tersebut termasuk tanah yang sedang berkembang lanjut dan mempunyai status kesuburan tanah rendah.The content of Free Fe, Al, and Si and Soil Fertility Status of Entisol and Inceptisol in Dryland of Jantho, Aceh Besar DistrictAbstract. In soils, the free of Fe, Al, and Si are generally found as a mineral that are the main composition of the soil in humid tropical dryland. The content of these elements in the soil can be extracted with dithionite-citrate solution. This research aims to know the content and distribution of free Fe, Al, and Si in the soil horizon layers of each soil order of Entisol (from Jalin), and Inceptisol (from Cucum and Buket Meusara vilages) of dryland of Jantho, Aceh Besar District and to evaluate the soil fertility status. Fe, Al, and Si were extracted with 0.1 N Na-dithionite-citrate (Holmgren, 1976) and measured their consentration by atomic absorption Spectrophotometry (AAS). The results showed that the content of free Fe on the third soil order are low (0.01 -1.43%) while free Al of soil varies between soil order and range from low to high (1.60-11.72%). The content of free Si on the third soil order in dryland of Jantho also varies from low to high (1.48-13.05%). The lowest free Fe content of soil found at Inceptisol Cucum, while the lowest free Al and Si content found at Inceptisol Buket Meusara. Based on the Fe, Al, and Si composition, the third soil order includes as developing advanced soils which low soil fertility status.

In vitro litholytic activity of extracts and phenolic fractions of some medicinal plants on urinary stones

Objective: This study was carried out to evaluate the efficiency of plant extracts used in traditional medicine on the dissolution of oxalo-calcic and cystine stones. Also, the efficiency of phenolic fractions (Tannins and Flavonoids) for the plants that gave us the best stone dissolution rate. Subjects and methods: Kidney stone of oxalo-calcic and cystine stones were incubated in vitro for 8 weeks in the presence of five plants extracts (hydro-ethanolic and aqueous extracts). NaCl solution (0,9 %) used as negative control and sodium citrate solution at 3 mM/L as a positive control. The studied plants were Herniaria hirsuta L. aerial parts, Opuntia ficus-indica L. flowers, Zea mays L. stigmata, Ammi visnaga L. seeds and Ziziphus lotus L. fruits. After 2, 4, 6 and 8 weeks the stones were weighed after 18 h drying at 40°C and the dissolution rate of the stones and the pH of the solution were measured.Results: After eight weeks, all the plant extracts and phenolic fractions had revealed a significant effect to dissolve oxalo-calcic and cystine stones in comparison to the control solutions. The best result of cystine stones was showed with aqueous extract of H. hirsuta aerial parts which had a dissolution rate of 88,91 %. Concerning the dissolution rate of oxalo-calcic stones the aqueous extract of Z. mays had the best results with 68 % against 19 % for the sodium citrate solution. The dissolution rate of the fractions studied showed a better result for Z. mays flavonoids fraction toward oxalo-calcic stones, and Z. mays tannins fraction for cystine stones. The pH undergoes a non-negligible linear increase over the eight weeks for all extracts and phenolic fractions and both kidney stones.Conclusion: The tested plants' extracts and the phenolic fractions for the plants that gave us the best stone dissolution rate were able to dissolve oxalo-calcic and cystine stones. To confirm the efficiency of these plant extracts on the treatment of oxalo-calcic and cystine stones multiple in vivo tests could be made.