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PubMedDate not supplied

Phosphorylation of citrate lyase ligase in Clostridium sphenoides and regulation of anaerobic citrate metabolism in other bacteria.

Since anaerobic bacteria cannot take advantage of citrate oxidation through the reactions of the tricarboxylic acid cycle special enzymes are needed for its fermentation. The activity of citrate lyase (the key enzyme of the citrate fermentation pathway) is in most cases strictly controlled by acetylation/deacetylation and configurational changes. In order to efficiently regulate citrate metabolism the activity of various regulatory enzymes, that modulate citrate lyase activity, are in turn under stringent control. Covalent modification by phosphorylation/dephosphorylation and electron transport dependent processes are some of the regulatory mechanisms that are here involved. L-Glutamate, which signals the availability of citrate, plays a central role in the regulation of citrate metabolism by influencing the enzymes that are acting in a complex cascade system.

ATP Citrate (pro-S)-Lyase↗
PubMed2000

Characterization of a bovine cDNA encoding citrate synthase, and presence of citrate synthase mRNA during bovine pre-attachment development.

Citrate synthase is a key regulatory metabolic enzyme that catalyzes the first step in the tricarboxylic acid (TCA) cycle, the synthesis of citrate from acetyl coenzyme A and oxaloacetate. Aerobic metabolism via the TCA cycle is high in bovine embryos at the 4-cell stage then decreases until the compact morula stage before increasing at the expanded blastocyst stage. This study characterizes the presence of citrate synthase mRNA in bovine pre-attachment embryos to determine if a variation in mRNA transcript expression patterns is associated with previous reports of the patterns of TCA cycle activity. The reverse transcription-polymerase chain reaction (RT-PCR) method was used to detect citrate synthase mRNA from the 1-cell to blastocyst stage of bovine embryo development, and in embryos cultured under either an atmosphere of 5% CO(2) in air or 5% CO(2)/5% O(2)/90%N(2). The nucleotide sequence encoding citrate synthase was determined from bovine heart cDNA by the rapid amplification of cDNA ends (RACE) technique. This 1455-bp nucleotide fragment contained an open reading frame that encoded a deduced protein of 466 amino acids. The bovine nucleotide sequence was 92.1% and 93.8% identical to the human and porcine coding sequence, respectively. The amino acid sequence predicted from the bovine sequence is 95.1% identical to the human sequence and 96.3% identical to the porcine sequence. The porcine sequence contains a stop codon that results in a peptide truncated by 2 amino acids. The detection of citrate synthase transcripts from the 1-cell to blastocyst stage demonstrates that the decrease in TCA cycle activity observed following the 4-cell stage is not associated with an absence of citrate synthase mRNA.

Amino Acid Sequence↗
PubMed1985

Citrate effects on the Ca2+-loading capacity of isolated rat liver mitochondria: interaction of citrate and ATP.

The maximal amounts of Ca2+ being accumulated (delta Ca2+max) and H+ emitted (delta H+max) by Ca2+-loading mitochondria, with succinate (+rotenone) as respiratory substrate, were evaluated. delta Ca2+max was increased by providing either citrate or ATP to a Pi- and Mg2+-free medium. With citrate, delta H+max was only scarcely increased, so that the effect of the proton-carrying anion resulted essentially from an increase in the Ca2+/H+ ratio, i.e., from preservation of membrane potential. With ATP (+/- oligomycin), the Ca2+/H+ ratio was unaltered; i.e., the increase of delta Ca2+max was paralleled by a related increase in delta H+max. Mitochondria appeared to retain Ca at higher delta pH, i.e., at lower membrane potential, in the presence of ATP. With citrate and ATP together, both the Ca2+/H+ ratio and delta H+max were largely increased, and the product of these two terms, delta Ca2+max, was considerably enlarged. The effect of either citrate or ATP was markedly reinforced in the presence of the other anion. In addition to increasing the Ca2+/H+ ratio, citrate contributed to increasing delta H+max in the presence of ATP, i.e., apparently sensitized mitochondria to the action of ATP. A citrate-induced depression of Ca2+ cycling across the inner membrane, even though pronounced, did not account for the sensitization. Supraadditive effects of citrate and ATP persisted in the presence of MgCl2 and Pi, under conditions of massive Ca2+ loading, and may contribute to the high capacity of mitochondria, in situ, to retain calcium.

Adenosine Triphosphate↗
PubMed1968

The metabolic fate of the products of citrate cleavage. Adenosine triphosphate-citrate lyase and nicotinamide-adenine dinucleotide phosphate-linked malate dehydrogenase in foetal and adult liver from ruminants and non-ruminants.

1. Foetal rat liver slices incorporate the C-3 of aspartate and C-2 of glutamate into fatty acids at rates equal to those observed with adult rat liver slices. Incorporation of either of these labelled carbon atoms into fatty acids would require a functioning citrate-cleavage pathway which consists of the enzymes ATP-citrate lyase, NAD-malate dehydrogenase and NADP-malate dehydrogenase. However, NADP-malate dehydrogenase is present in foetal rat liver at only 5% of the activity detectable in adult rat liver. 2. From these findings and the effect of cofactors on the formation of (14)CO(2) from [1,5-(14)C(2)]citrate in liver supernatant fractions (100000g), it is suggested that NADP-malate dehydrogenase limits the citrate-cleavage sequence. 3. Measurement of the citrate-cleavage pathway by incorporation studies with [3-(14)C]aspartate and [U-(14)C]glucose and by determining the activities of ATP-citrate lyase and NADP-malate dehydrogenase have shown that this sequence of reactions is present in the liver of the bovine foetus but not in the adult. However, C-2 of glutamate is not incorporated into fatty acids or non-saponifiable lipid by bovine liver slices. This finding as well as those presented above for the adult and foetal rat liver are interpreted on the basis of a competition between phosphoenolpyruvate carboxykinase and NAD-malate dehydrogenase for oxaloacetate produced by the cleavage of citrate in the cytosol.

Adenosine Triphosphate↗
PubMed1996

The lack of influence of long-term potassium citrate and calcium citrate treatment in total body aluminum burden in patients with functioning kidneys.

BACKGROUND: It has been suggested that citrate salts might enhance aluminum (Al) absorption from a normal diet, posing a threat of Al toxicity even in subjects with normal renal function. We have recently reported that in normal subjects and patients with moderate renal failure, short-term treatment with tricalcium dicitrate (Ca3Cit2) does not significantly change urinary and serum Al levels. However, we have not assessed total body Al stores in patients on long-term citrate treatment. OBJECTIVE: The objective of this study was to ascertain body content of Al non-invasively using the increment in serum and urinary Al following the intravenous administration of deferoxamine (DFO) in patients with kidney stones and osteoporotic women undergoing long-term treatment with potassium citrate (K3Cit) or Ca3Cit2, respectively. METHODS: Ten patients with calcium nephrolithiasis and five with osteoporosis who were maintained on potassium citrate (40 mEq/day or more) or calcium citrate 800 mg calcium/day (40 mEq citrate) for 2 to 8 years, respectively, and 16 normal volunteers without a history of regular aluminum-containing antacid use participated in the study. All participants completed the 8 days of study, during which they were maintained on their regular home diet. Urinary Al excretion was measured during a two-day baseline before (Days 5, 6) and for 1 day (Day 7) immediately following a single intravenous dose of DFO (40 mg/kg). Blood for Al was obtained before DFO administration, and at 2, 5 and 24 hours following the start of the infusion. RESULTS: The median 24-hour urinary Al excretion (microgram/day) at baseline versus post-DFO value was 15.9 vs. 44.4 in the normal subjects and 13.3 vs. 35.7 in the patients. These values were all within normal limits and did not change significantly following DFO infusion (p = 0.003 and p = 0.0001, respectively). The median change of 17.1 micrograms/day in urinary Al in the normal subjects was not significantly different from the 18.7 micrograms/day change measured in the patient group (p = 0.30). Similarly, no change in the mean serum Al was detected at any time following the DFO infusion, either in the patient or control group (patients 4.1 to 4.3 ng/ml, controls 7.4 to 4.6 ng/ml). CONCLUSION: The results suggest that abnormal total body retention of Al does not occur during long-term citrate treatment in patients with functioning kidneys.

Adult↗
PubMed1996

Secondary transporters for citrate and the Mg(2+)-citrate complex in Bacillus subtilis are homologous proteins.

Citrate uptake in Bacillus subtilis is mediated by a secondary transporter that transports the complex of citrate and divalent metal ions. The gene coding for the transporter termed CitM was cloned, sequenced, and functionally expressed in Escherichia coli. Translation of the base sequence to the primary sequence revealed a transporter that is not homologous to any known secondary transporter. However, CitM shares 60% sequence identity with the gene product of open reading frame N15CR that is on the genome of B. subtilis and for which no function is known. The hydropathy profiles of the primary sequences of CitM and the unknown gene product are very similar, and secondary structure prediction algorithms predict 12 transmembrane-spanning segments for both proteins. Open reading frame N15CR was cloned and expressed in E. coli and was shown to be a citrate transporter as well. The transporter is termed CitH. A remarkable difference between the two transporters is that citrate uptake by CitM is stimulated by the presence of Mg2+ ions, while citrate uptake by CitH is inhibited by Mg2+. It is concluded that the substrate of CitM is the Mg(2+)-citrate complex and that CitH transports the free citrate anion. Uptake experiments in right-side-out membrane vesicles derived from E. coli cells expressing either CitM or CitH showed that both transporters catalyze electrogenic proton/substrate symport.

Bacillus subtilis↗
PubMed1991

[An enzymatic determination of serum citrate with citrate lyase].

A method for the enzymatic determination of the serum citrate using citrate lyase is described. The optimum pH was equal to or higher than 8.6. Prior to the determination of the serum citrate, the samples were deproteinized with perchloric acid. After the precipitation of the proteins, potassium hydroxide was added under an ice-cooling condition in order to neutralize the solution. The recovery rates of the citrate added to serum ranged from 92% to 108%, and the coefficient of variation of triplicate assay was 4.2%. The mean serum value of 17 healthy subjects was 1.57 mg/dl, with a range of 1.03-2.03 mg/dl. In seven healthy subjects, 3 g of sodium-potassium citrate was administered orally and the serum citrate was measured 0, 15, 30, 45, 60, and 120 min later. The serum citrate was significantly increased in the periods between 15 and 60 min.

Adult↗
PubMed1975

Fluorometry of citrate in serum, with use of citrate (pro-3S)-lyase.

We describe a procedure for enzymatic assay of citrate in human serum. The citrate is degraded to acetate and oxaloacetate with citrate oxaloacetate-lyase (pro-3S-CH2-COO- yields acetate) (EC 4.1.3.6). Some oxaloacetate loses CO2 to form pyruvate. Addition of malate and lactate dehydrogenases (EC 1.1.1.37 and 1.1.1.27) permits determination of the oxaloacetate and pyruvate generated, and thus of the citrate concentration. The decrease in NADH concentration is measured fluorometrically. Results obtained for 30 consecutive human sera by this procedure were compared to the procedure in which the citrate is converted to pentabromoacetone. There was no statistically significant difference in values obtained by the two procedures. The range of values (mean plus or minus 2 SD) found for sera from 25 blood donors by this procedure was 12.8-27.2 mg/liter (mean, 19.0 mg/liter). Serum citrate as measured by both procedures during a glucose tolerance test was decreased from initial values under the influence of administered glucose (and endogenous insulin). Insulin concentrations were also measured during these glucose-tolerance tests. Citrate concentrations remain subnormal after the glucose and insulin concentrations return to their initial values. This accords with published reports.

Acetone↗
PubMed1987

Effects of sodium citrate, potassium citrate, and citric acid in preventing experimental calcium oxalate urolithiasis in rats.

Male Wistar-strain rats which had been fed a glycolic-acid diet developed severe nephrocalcinosis with urinary calculi within 4 weeks. Rats fed the same diet with citrate salts added had, however, either slight or no nephrocalcinosis without any stones in the urinary system. Nephrocalcinosis intermediate between those in the citrate groups and the glycolic-acid group, with some urinary calculi, was observed in the citric-acid group. During the experiment, the urinary oxalate concentration increased markedly and was higher in the citrate and citric-acid than in the glycolic-acid group. The urinary citrate concentration was significantly higher in the citrate groups and lower in the citric acid and glycolic-acid groups. Therefore, citrate salts can be concluded to inhibit nephrocalcinosis and calculi formation as a result of decreased urinary saturation by means of increase in urinary citrate, in spite of a slight increase in the urinary oxalate.

Animals↗
PubMed1981

ATP-citrate lyase kinase and cyclic AMP-dependent protein kinase phosphorylate different sites on ATP-citrate lyase.

ATP-citrate lyase was phosphorylated by highly purified cyclic AMP-independent protein kinase (ATP-citrate lyase kinase) or the catalytic subunit of cyclic AMP-dependent protein kinase. Each kinase phosphorylated ATP-citrate lyase equally but the combination of both kinases increased ATP-citrate lyase phosphorylation additively. When ATP-citrate lyase was phosphorylated with each kinase and partially digested with either L-1-tosylamido-2-phenylmethyl chloromethyl ketone-treated trypsin or Staphylococcus aureus protease followed by electrophoresis of the proteolytic products on sodium dodecyl sulfate-polyacrylamide gels or when the phosphorylated lyase was completely digested by these proteases followed by chromatography and electrophoresis, the results showed that the site phosphorylated by ATP-citrate lyase kinase was different from that phosphorylated by the catalytic subunit of cyclic AMP-dependent protein kinase. Only phosphoserine was found in lyase phosphorylated by the catalytic subunit of cyclic AMP-dependent protein kinase whereas phosphoserine and phosphothreonine were found in ATP-citrate lyase phosphorylated by lyase kinase.

ATP Citrate (pro-S)-Lyase↗
PubMed1995

Citrate in urine determined with a new citrate lyase method.

An enzyme-spectrophotometric method to determine citrate in biological fluids is proposed, based on citrate lyase-catalyzed and phenylhydrazine reactions. The enzyme converts citrate into oxaloacetate, which, in the presence of phenylhydrazine, is transformed into the corresponding phenylhydrazone. The ultraviolet-absorbing product is determined by absorbance measurement at 330 nm. The method is more precise and twice as sensitive as the traditional citrate lyase method and, because it does not require the use of additional enzymes and coenzymes, is cheaper and simpler. Mean analytical recovery of citrate averaged 100.7% +/- 2.2%, imprecision (CV) of the assay for citrate at 0.96 mmol/L (urine) was 2.0%, and the lower limit of quantification was 0.08 mmol/L. Results correlated well with those by both ion-chromatographic and traditional citrate lyase methods.

Citrates↗
PubMed2006

Clomiphene citrate plus N-acetyl cysteine versus clomiphene citrate for augmenting ovulation in the management of unexplained infertility: a randomized double-blind controlled trial.

OBJECTIVE: To compare clomiphene citrate with N-acetyl cysteine vs. clomiphene citrate alone for augmenting ovulation in management of unexplained infertility. DESIGN: Prospective randomized double-blind controlled trial. SETTING: Department of obstetrics and gynecology in a university medical faculty in Egypt. PATIENT(S): Four hundred four patients as a study group (clomiphene citrate plus N-acetyl cysteine group) and 400 patients as a control group (clomiphene citrate-alone group). All women had unexplained infertility. INTERVENTION(S): Patients in the study group were treated with clomiphene citrate (50-mg tablets) twice per day and with N-acetyl cysteine (1,200 mg/d orally) for 5 days starting on day 2 of the cycle. Patients in the control group were treated with clomiphene citrate with sugar powder. MAIN OUTCOME MEASURE(S): The primary outcomes were number and size of growing follicles, serum E(2), serum P, and endometrial thickness. The secondary outcome was the occurrence of pregnancy. RESULT(S): There were no statistically significant differences between the two groups in the number of follicles sized >18 mm, mean E(2) levels, serum P, or endometrial thickness. Pregnancy rate was comparable in both groups (22.2% vs. 27%). Miscarriage rate was comparable in both groups (6.7% in the study group vs. 7.4% in the control group). CONCLUSION(S): N-Acetyl cysteine is ineffective in inducing or augmenting ovulation in patients with unexplained infertility and cannot be recommended as an adjuvant to clomiphene citrate in such patients.

Acetylcysteine↗
PubMed2004

Thromboelastography with citrated blood: comparability with native blood, stability of citrate storage and effect of repeated sampling.

Thromboelastography (TEG) with recalcified citrate blood is used as an alternative to native blood, but there is insufficient data regarding sample reliability and stability over time. Thus, TEG parameters of freshly drawn native blood were compared with those of recalcified citrated blood without celite in 10 healthy subjects, and the effect of repeated sampling over 240-min storage was evaluated. All TEG parameters following citrate storage remained stable between 30 min [clot formation time (k) = 7.2 +/- 0.6 min; maximum amplitude (ma) = 48.5 +/- 1.9 mm] and 2 h (k = 7.1 +/- 0.6 min; ma = 46.2 +/- 2.5 mm) after initial sampling, but were not comparable with native blood (k = 9.3 +/- 0.7 min; ma = 43.5 +/- 2.5 mm) at any time point. TEG parameters of repeatedly sampled citrated blood had a significant overall hypercoagulable trend throughout 4 h following sampling. In conclusion, in order to achieve reproducible results, citrated blood without celite may be utilized between 30 min and 2 h following sampling, but in normal subjects the TEG parameters following citrate storage are not comparable with native blood, possibly because of incomplete inhibition of the activation of the coagulation cascade. Thus, citrated blood can be used as a surrogate of native blood in assessing coagulation using TEG, but if repeated sampling is used the trend in hypercoagulability must be considered.

Anticoagulants↗
PubMed2005

Citrate anticoagulation during plasma exchange in a patient with thrombotic thrombocytopenic purpura: short heparin-free hemodialysis helps to attenuate citrate load.

The treatment of thrombotic thrombocytopenic purpura requires plasma exchange using fresh frozen plasma as a replacement solution once or even twice daily. If citrate anticoagulation is needed, the citrate load (both from fresh frozen plasma and citrate as an anticoagulant) can be significant, causing metabolic complications. The aim of our report is to present our experience with citrate anticoagulation in a patient with thrombotic thrombocytopenic purpura treated with daily membrane plasma exchange. Twenty-six plasma exchange procedures were performed during 20 days of treatment in a 46-year-old female. The blood flow was 98 +/- 8 mL/min; 4% trisodium citrate was infused into the arterial line (134 +/- 11 mL/h) and 1 M CaCl2 into the venous line (11.4 +/- 1.8 mL/h). Fresh frozen plasma (first 7 procedures) or cryo-poor plasma (19 procedures) were used as a replacement solution, 3176 +/- 536 mL per procedure. A total of 88,930 mL of plasma was exchanged. No serious side-effects occurred. iCa before plasma exchange was significantly higher than afterwards (1.23 +/- 0.12 vs. 1.12 +/- 0.12, P = 0.0047). Significant alkalosis occurred after three plasma exchanges (pH 7.64, bicarbonate 36.2 mmol/L), and was corrected by 3-h heparin-free hemodialysis with dialysate as follows: K 4.0 mmol/L, calcium 1.5 mmol/L, and bicarbonate set to 24 mmol/L. After dialysis, pH was 7.45 and bicarbonate 29.4 mmol/L. Another (2-h) heparin-free hemodialysis procedure was repeated after six plasma exchanges. Citrate anticoagulation can be safely performed in patients treated with plasma exchange once or twice daily. Periodically performed short heparin-free hemodialysis can correct metabolic alkalosis and attenuate the citrate load.

Alkalosis↗
PubMed1998

Mechanism of the citrate transporters in carbohydrate and citrate cometabolism in Lactococcus and Leuconostoc species.

Citrate metabolism in the lactic acid bacterium Leuconostoc mesenteroides generates an electrochemical proton gradient across the membrane by a secondary mechanism (C. Marty-Teysset, C. Posthuma, J. S. Lolkema, P. Schmitt, C. Divies, and W. N. Konings, J. Bacteriol. 178:2178-2185, 1996). Reports on the energetics of citrate metabolism in the related organism Lactococcus lactis are contradictory, and this study was performed to clarify this issue. Cloning of the membrane potential-generating citrate transporter (CitP) of Leuconostoc mesenteroides revealed an amino acid sequence that is almost identical to the known sequence of the CitP of Lactococcus lactis. The cloned gene was expressed in a Lactococcus lactis Cit- strain, and the gene product was functionally characterized in membrane vesicles. Uptake of citrate was counteracted by the membrane potential, and the transporter efficiently catalyzed heterologous citrate-lactate exchange. These properties are essential for generation of a membrane potential under physiological conditions and show that the Leuconostoc CitP retains its properties when it is embedded in the cytoplasmic membrane of Lactococcus lactis. Furthermore, using the same criteria and experimental approach, we demonstrated that the endogenous CitP of Lactococcus lactis has the same properties, showing that the few differences in the amino acid sequences of the CitPs of members of the two genera do not result in different catalytic mechanisms. The results strongly suggest that the energetics of citrate degradation in Lactococcus lactis and Leuconostoc mesenteroides are the same; i.e., citrate metabolism in Lactococcus lactis is a proton motive force-generating process.

Amino Acid Sequence↗
PubMed2006

Effect of clomifene citrate plus metformin and clomifene citrate plus placebo on induction of ovulation in women with newly diagnosed polycystic ovary syndrome: randomised double blind clinical trial.

OBJECTIVE: To compare the effectiveness of clomifene citrate plus metformin and clomifene citrate plus placebo in women with newly diagnosed polycystic ovary syndrome. DESIGN: Randomised clinical trial. SETTING: Multicentre trial in 20 Dutch hospitals. PARTICIPANTS: 228 women with polycystic ovary syndrome. INTERVENTIONS: Clomifene citrate plus metformin or clomifene citrate plus placebo. MAIN OUTCOME MEASURE: The primary outcome measure was ovulation. Secondary outcome measures were ongoing pregnancy, spontaneous abortion, and clomifene resistance. RESULTS: 111 women were allocated to clomifene citrate plus metformin (metformin group) and 114 women were allocated to clomifene citrate plus placebo (placebo group). The ovulation rate in the metformin group was 64% compared with 72% in the placebo group, a non-significant difference (risk difference - 8%, 95% confidence interval - 20% to 4%). There were no significant differences in either rate of ongoing pregnancy (40% v 46%; - 6%, - 20% to 7%) or rate of spontaneous abortion (12% v 11%; 1%, - 7% to 10%). A significantly larger proportion of women in the metformin group discontinued treatment because of side effects (16% v 5%; 11%, 5% to 16%). CONCLUSION: Metformin is not an effective addition to clomifene citrate as the primary method of inducing ovulation in women with polycystic ovary syndrome. TRIAL REGISTRATION: Current Controlled Trials ISRCTN55906981 [controlled-trials.com].

Adult↗
PubMed2005

A prospective, randomized, double-blind crossover study on the use of 5% citrate lock versus 10% citrate lock in permanent hemodialysis catheters.

Central venous catheters are used as permanent vascular access for chronic hemodialysis when construction of an arteriovenous fistula is not possible or contraindicated. We prospectively evaluated the efficacy and safety of a 5% citrate versus 10% citrate catheter lock for permanent single-lumen dialysis catheters in a double-blind, crossover study of 28 patients during 1,876 dialysis sessions. There was a slightly higher number of dialysis sessions with clot formation in the 5% citrate group; entirely attributable to the formation of small clots. There was no statistically significant difference in the formation of large clots, complete obstruction of the catheter or the need for urokinase between the 2 study groups. In view of the ongoing debate on the safety of high-concentration citrate catheter locks, we conclude that a 5% citrate lock is equally efficient in preventing catheter dysfunction compared with a 10% citrate lock and is therefore the preferred citrate catheter-locking solution.

Aged↗
PubMed2002

Regional citrate anticoagulation using a citrate-based substitution solution for continuous venovenous hemofiltration in cardiac surgery patients.

OBJECTIVE: To evaluate the feasibility, efficacy, safety and side effects of routinely performed continuous venovenous hemofiltration (CVVH) with regional citrate anticoagulation using a citrate-containing substitution solution as compared with conventional systemic low-dose unfractionated heparin-anticoagulation in postoperative cardiac surgery patients. DESIGN/SETTING: Database review of all patients on CVVH during a three-year period at a cardiovascular intensive care unit of a tertiary referring university hospital. PATIENTS: Patients who had undergone cardiac surgery with acute or chronic renal failure were studied. Thirty-seven citrate CVVH courses in 31 patients (January to November 2000) and 59 heparin CVVH courses in 50 patients (1998 and 1999) had been undertaken postoperatively. Indications for hemofiltration were acute renal failure in 24 and chronic renal failure in 7 of the citrate patients, and acute renal failure in 44 and chronic renal failure in 6 of the heparin patients. INTERVENTIONS: CVVH with either regional citrate anticoagulation using a custom-made citrate-based substitution solution or unfractionated heparin anticoagulation. MEASUREMENTS: The following parameters were measured: median filtration time, hemofilters used per day, differences in creatinine and blood urea levels as opposed to baseline, blood loss within the first 24 h of hemofiltration, incidence of bleeding-related resternotomies, acidosis, and alkalosis. RESULTS: No significant differences in any of the measured parameters were registered. No serious electrolyte imbalance was observed in either group. Furthermore, the two groups did not differ in terms of mortality, duration of stay in the intensive care unit or in hospital, and restoration rate of normal renal function. CONCLUSIONS: We conclude that citrate-based regional anticoagulation is effective, safe and easy to use in CVVH following cardiac surgery and might become the first choice for anticoagulation in patients in whom the application of systemic heparin is contraindicated.

Aged↗