Determinants of Total/ionized Calcium in patients undergoing citrate CVVH: A retrospective observational study (original) (raw)

Calcium Mass Balance during Citrate Hemodialysis: A Randomized Controlled Trial Comparing Normal and Low Ionized Calcium Target Ranges

PloS one, 2016

Regional citrate anticoagulation (RCA) during hemodialysis interferes with calcium homeostasis. Optimal ionized calcium (iCa) target range during RCA and consequent calcium balance are unknown. In a randomized controlled trial (ACTRN12613001029785) 30 chronic hemodialysis patients were assigned to normal (1.1-1.2 mmol/) or low (0.95-1.05 mmol/l) iCa target range during a single hemodialysis with RCA. The primary outcome was calcium mass balance during the procedure, using a partial spent dialysate collection method; magnesium mass balance was also measured. Intact parathormone (iPTH), total calcium (tCa) and magnesium were measured before and after procedures. Mean iCa during procedures was significantly different in the two groups (1.12±0.06 in normal and 1.06±0.07 mmol/l in low iCa group, p <0.001), resulting in different tCa (2.18±0.22 vs. 1.95±0.17, p = 0.003) after the procedure. Mean delivered calcium during the procedure was 58.3±4.8 mmol in the normal and 51.5±8.2 mmol in...

Regional citrate anticoagulation and influence of recirculation on ionized calcium levels in the circuit

Journal of Artificial Organs, 2019

Regional citrate anticoagulation is now widely used during continuous renal replacement therapy (CRRT), and especially in patients at risk for hemorrhagic complications. A close monitoring is required to avoid citrate overload, leading to metabolic alkalosis or citrate intoxication causing metabolic acidosis. This case report describes a dysfunction of the regional citrate anticoagulation due to the development of a deep vein thrombosis close to the site of insertion of the venous CRRT catheter. The result was a local recirculation in the circuit with a local citrate overload (acidosis and non-measurable calcium). In the patient's blood samples, the [calcium total /Ca 2+ systemic ] ratio remained normal as a proof of local citrate accumulation without systemic effects. Initially, CRRT remained effective, but due to the progressive decrease of serum creatinine and cystatin C clearance, the site of catheter insertion was changed.

Discrepant post filter ionized calcium concentrations by common blood gas analyzers in CRRT using regional citrate anticoagulation

Critical Care, 2015

Introduction Ionized calcium (iCa) concentration is often used in critical care and measured using blood gas analyzers at the point of care. Controlling and adjusting regional citrate anticoagulation (RCA) for continuous renal replacement therapy (CRRT) involves measuring the iCa concentration in two samples: systemic with physiological iCa concentrations and post filter samples with very low iCa concentrations. However, modern blood gas analyzers are optimized for physiological iCa concentrations which might make them less suitable for measuring low iCa in blood with a high concentration of citrate. We present results of iCa measurements from six different blood gas analyzers and the impact on clinical decisions based on the recommendations of the dialysis’ device manufacturer. Method The iCa concentrations of systemic and post filter samples were measured using six distinct, frequently used blood gas analyzers. We obtained iCa results of 74 systemic and 84 post filter samples from...

Standard versus no post-filter ionized calcium monitoring in regional citrate anticoagulation for continuous renal replacement therapy (NPC trial)

Clinical Kidney Journal

Background Current guidelines recommend monitoring of post-filter ionized calcium (pfCa) when using regional citrate anticoagulation during continuous renal replacement therapy (RCA-CRRT) to determine citrate efficiency for prevention of filter clotting. However, the reliability of pfCa raises the question of whether routine monitoring is required. Reducing the frequency of pfCa monitoring could potentially reduce costs and workload. Our objective was to test the efficacy and safety of no pfCa monitoring among critically ill patients receiving RCA-CRRT. Methods This study was a non-inferiority randomized controlled trial conducted between January 2021 and October 2021 at King Chulalongkorn Memorial Hospital, Thailand. Critically ill patients who were treated with RCA-CRRT were randomized to receive either standard pfCa monitoring (aiming pfCa level of 0.25-0.35 mmol/L), or no pfCa monitoring, in which a constant rate of citrate infusion was maintained at pre-determined citrate conce...

Citrate dose for continuous hemofiltration: effect on calcium and magnesium balance, parathormone and vitamin D status, a randomized controlled trial

BMC Nephrology

Background Regional citrate anticoagulation may cause a negative calcium balance, systemic hypocalcemia and parathormone (PTH) activation but randomzed studies are not available. Aim was to determine the effect of citrate dose on calcium (Ca) and magnesium (Mg) balance, PTH and Vitamin D. Methods Single center prospective randomized study. Patients, requiring continuous venovenous hemofiltration (CVVH) with citrate, randomized to low dose citrate (2.5 mmol/L) vs. high dose (4.5 mmol/L) for 24 h, targeting post-filter ionized calcium (pfiCa) of 0.325–0.4 mmol/L vs. 0.2–0.275 mmol/L, using the Prismaflex® algorithm with 100% postfilter calcium replacement. Extra physician-ordered Ca and Mg supplementation was performed aiming at systemic iCa > 1.0 mmol/L. Arterial blood, effluent and post-filter aliquots were taken for balance calculations (area under the curve), intact (i), oxidized (ox) and non-oxidized (nox) PTH, 25-hydroxy-Vitamin D (25D) and 1,25-dihydroxy-Vitamin D (1,25D). R...

Comparison of pre-filter and post-filter ionised calcium monitoring in continuous veno-venous hemodiafiltration (CVVHD-F) with citrate anti-coagulation

PloS one, 2017

It is widespread practice during citrate anticoagulated renal replacement therapy to monitor circuit ionised calcium (iCa2+) to evaluate the effectiveness of anticoagulation. Whether the optimal site to sample the blood path is before or after the haemofilter is a common question. Using a prospectively collected observational dataset from intensive care patients receiving pre-dilution continuous veno-venous haemodiafiltration (CVVHD-F) with integrated citrate anticoagulation we compared paired samples of pre and post filter iCa2+ where the target range was 0.3-0.5 mmol.L-1 as well as concurrently collected arterial iCa2+. Two nested mixed methods linear models were fitted to the data describing post vs pre filter iCa2+, and the relationship of pre, post and arterial samples. An 11 bed general intensive care unit. 450 grouped samples from 152 time periods in seven patients on CRRT with citrate anticoagulation. The relationship of post to pre-filter iCa2+ was not 1:1 with post = 0.082...

Presence of valvular calcification predicts the response to cinacalcet: data from the ADVANCE study

The Journal of heart valve disease, 2013

Cardiac valve calcification (CVC) and coronary artery calcification (CAC) appear to be linked pathogenetically, and both are associated with a poor prognosis among patients with chronic kidney disease on dialysis (CKD-5D). Little is known, however, about factors that affect the progression of CVC and CAC. A post-hoc analysis was performed of the ADVANCE study to assess whether patients with CVC are more prone to CAC progression, and whether CVC predicts the response to different treatments for secondary hyperparathyroidism. Subjects were randomized to treatment with either cinacalcet and low doses of vitamin D analogs or larger, varying doses of vitamin D. Among 235 subjects, aortic valve or mitral valve calcification was detected in 108 (46%) and 118 (50%), respectively; 69 subjects (29%) had calcification of both valves. CVC was associated both with baseline CAC and CAC progression (p < 0.05). Subjects with aortic valve calcification who were treated with cinacalcet and low dos...

Stability of ionized calcium measurements at concentrations less than 0.3 mmol/L by point-of-care blood gas instruments: application for postfilter calcium quality control in patients with citrate anticoagulation during extracorporeal circulation

Annals of Clinical Biochemistry: International Journal of Laboratory Medicine, 2017

Background Measurements of ionized calcium (Ca2+) at concentrations less than 0.3 mmol/L are required for postfilter control in patients who receive extracorporeal circulation with sodium citrate anticoagulation. This study evaluates the stability of the Ca2+ measurements at such concentrations. Methods The stability of the Ca2+ measurements was tested by measuring daily the external standard Qualicheck concentration 3 s7950, Radiometer (0.22–0.25 mmol/L) by blood gas instruments ABL800 and ABL90, Radiometer. Two different Ca2+ membrane lots were tested for the usual membrane lifetime of 12 weeks at ABL800 instruments. For the ABL90 instrument, the sensor cassette (with Ca2+ membrane and electrode) was replaced after four weeks as required. Results We observed over 40% Ca2+ increase within the usual 12 weeks lifetime of the Ca2+ membrane at the ABL800 instruments. Measurements of Ca2+ at concentrations less than 0.3 mmol/L were within acceptable limits for both ABL800 and ABL90 inst...

Course of Ionized Calcium After Thyroidectomy

World Journal of Surgery, 2010

Background The goal of the present study was to investigate the course of ionized calcium after thyroidectomy and to define a cutoff value that indicates symptoms of hypocalcemia. Methods The sample included 333 patients undergoing thyroidectomy at the University Hospital of UFMG between September 2000 and December 2005. Ionized calcium was determined before and after surgery (days 1, 2, and 30) in all patients and on postoperative days 90 and 180 in those with hypocalcemia. Asymptomatic patients received no calcium replacement therapy, irrespective of calcium concentration. Patients with clinical manifestation of hypocalcemia were treated after laboratory confirmation. The presence or absence of postoperative hypocalcemia was associated with ionized calcium concentration measured on the reported days. Results Ionized calcium declined on the first two days after surgery in all patients when compared to preoperative levels (P = 0.000). Forty-seven (34.6%) of the 136 (40.8%) patients with postoperative hypocalcemia had symptoms. Patients with symptomatic hypocalcemia had significantly lower ionized calcium levels than those with asymptomatic hypocalcemia (P = 0.001). Fourteen (4.2%) patients progressed to definitive hypoparathyroidism by the end of 6 months. Conclusions Measurement of ionized calcium on postoperative days 1 and 2 is sufficient for the evaluation of post-thyroidectomy hypocalcemia. Ionized calcium concentrations \1.03 mmol/l on postoperative day 1 are indicative of the presence of symptoms and the need for treatment.