Regional Citrate Anticoagulation Research Articles

Calcium-Citrate Anticoagulation during Continuous Renal Replacement Therapy in Patients with Metformin Intoxication: A Case Series, Mathematical Estimation of Citrate Accumulation, and Literature Review

Plain Language SummaryMetformin intoxication is a potentially life-threatening condition characterized by severe metabolic acidosis that could require intensive care unit admission and renal replacement therapy (RRT) for metformin removal. According to current guidelines, a citrate solution is commonly administered to generate regional anticoagulation in RRT due to its effect on chelating ionized calcium, an essential element of the coagulation pathway. Citrate metabolism can be impaired during metformin intoxication, and its administration could lead to accumulation worsening the metabolic acidosis. Citrate is not routinely measured, and its accumulation is clinically diagnosed by the ratio between total and ionized plasma calcium concentration (T/I calcium ratio) >2.5 or estimating the presence of unmeasured anions (UA), calculating the strong ion gap (SIG), i.e., the difference between the strong anions and cation, and the concentration of bicarbonate, dissociated albumin, and phosphates. We compared our results obtained from a case series of three patients with a theoretical model of citrate accumulation. Finally, we reviewed the literature to unveil clinical practice in this scenario. Our results support that diluted citrate can be safely used for RRT in patients with metformin toxicity, and the SIG is a valuable tool to estimate the presence of UA and can be used to detect and monitor citrate accumulation in this context.

Association of anticoagulation use during continuous kidney replacement therapy and 90-day outcomes: A multicentre study.

Anticoagulation is recommended during continuous kidney replacement therapy (CKRT) to prolong the filter lifespan for optimal filter performance. We aimed to evaluate the effect of anticoagulation during CKRT on dialysis dependence and mortality within 90 days of intensive care unit (ICU) admission. Our retrospective observational study evaluated the first CKRT session in critically ill adults with acute kidney injury (AKI) in Singapore from April to September 2017. The primary outcome was a composite of dialysis dependence or death within 90 days of ICU admission; the main exposure variable was anticoagulation use (regional citrate anticoagulation [RCA] or systemic heparin). Multivariable logistic regression was performed to adjust for possible confounders: age, female sex, Acute Physiology and Chronic Health Evaluation (APACHE II) score, liver dysfunction, coagulopathy (international normalised ratio[INR] >1.5) and platelet counts of less than 100,000/uL). The study cohort included 276 patients from 14 participating adult ICUs, of whom 176 (63.8%) experienced dialysis dependence or death within 90 days of ICU admission (19 dialysis dependence, 157 death). Anticoagulation significantly reduced the odds of the primary outcome (adjusted odds ratio [AOR] 0.47, 95% confidence interval [CI] 0.27-0.83, P=0.009). Logistic regression analysis using anticoagulation as a 3-level indicator variable demonstrated that RCA was associated with mortality reduction (AOR 0.46, 95% CI 0.25-0.83, P=0.011), with heparin having a consistent trend (AOR 0.51, 95% CI 0.23-1.14, P=0.102). Among critically ill patients with AKI, anticoagulation use during CKRT was associated with reduced dialysis or death at 90 days post-ICU admission, which was statistically significant for regional citrate anticoagulation and trended in the same direction of benefit for systemic heparin anticoagulation. Anticoagulation during CKRT should be considered whenever possible.

Evaluation of the efficacy and associated complications of regional citrate anticoagulation in neonates: experience from a fourth level neonatal intensive care unit.

RCA was an efficient and safe anticoagulation for neonates requiring CKRT. Metabolic complications may occur, but they could be managed with adequate supplementation. • Continuous kidney replacement therapy (CKRT) has become popular in recent years due to its successful treatment of fluid overload, electrolyte imbalance, metabolic acidosis, multi-organ failure, and hyperleucinemia/hyperammonemia associated with inborn errors of metabolism. • The need for anticoagulation is the major difficulty in neonatal CKRT. In adult and pediatric patients, regional citrate anticoagulation has been shown to be effective. • RCA is an effective and safe anticoagulation method for neonates who require CKRT. • Electrolyte imbalances and metabolic acidosis could be managed with adequate supplementation and appropriate treatment parameters such as citrate dose, blood flow rate, and dialysate flow rate.

Safety of Citrate Anticoagulation in CKRT: Monocentric Experience of a Dynamic Protocol of Calcium Monitoring.

Regional Citrate Anticoagulation (RCA) is considered the first-line anticoagulation for Continuous Kidney Replacement Therapy (CKRT). The RCA requires strict protocols and trained staff to avoid unsafe use and ensure its benefit. We have analyzed all our CKRT prescriptions from December 2020 to April 2022 anonymously, collecting data on CKRT, lab tests, clinical conditions, and complications of RCA. In addition, in order to better detect citrate accumulation, we have performed an RCA protocol by reducing the CaTot/Ca2+ ratio cut-off from 2.50 to 2.40 and increasing the number of calcium checks according to its trend. Among the 374 patients in CKRT, 104 received RCA prescriptions, of which 11 (10.6%) were discontinued: 4 for the suspicion of citrate accumulation, 1 for the development of metabolic alkalosis, 1 for the shift to a different CKRT procedure due to the need for a higher bicarbonate dose, 4 for the elevation of hepatocytolysis indexes, and 1 due to a preemptive discontinuation following massive post-surgery bleeding. None of the patients have had citrate toxicity as indicated by a CaTot/Ca2+ greater than 2.50, and our protocol has allowed the early identification of patients who might develop clinical citrate toxicity.

Kinetics of small and middle molecule clearance during continuous hemodialysis

Regional citrate anticoagulation (RCA) enables prolonged continuous kidney replacement therapy (CKRT) filter lifespan. However, membrane diffusive performance might progressively decrease and remain unnoticed. We prospectively evaluated the kinetics of solute clearance and factors associated with decreased membrane performance in 135 consecutive CKRT-RCA circuits (35 patients). We recorded baseline patients’ characteristics and clinical signs of decreased membrane performance. We calculated effluent/serum ratios (ESR) as well as respective clearances for urea, creatinine and β2-microglobuline at 12, 24, 48 and 72 h after circuit initiation. Using mixed-effects logistic regression model analyses, we assessed the effect of time on those values and determined independent predictors of decreased membrane performance as defined by an ESR for urea < 0.81. We observed a minor but statistically significant decrease in both ESR and solute clearance across the duration of therapy for all three solutes. We observed decreased membrane performance in 31 (23%) circuits while clinical signs were present in 19 (14.1%). The risk of decreased membrane performance significantly increased over time: 1.8% at T1 (p = 0.16); 7.3% at T2 (p = 0.01); 15.7% at T3 (p = 0.001) and 16.4% at T4 (p < 0.003). Four factors present within 24 h of circuit initiation were independently associated with decreased membrane performance: arterial blood bicarbonate level (OR 1.50; p < 0.001), activated partial thromboplastin time (aPTT; OR = 0.93; p = 0.02), fibrinogen level (OR 6.40; p = 0.03) and Charlson score (OR 0.10; p < 0.01). COVID-19 infection was not associated with increased risk of decreased membrane performance. Regular monitoring of ESR might be appropriate in selected patients undergoing CKRT.

Feasibility, Efficacy, and Safety of Peripheral Venous Access for Chronic Double-Filtration Plasmapheresis with Regional Citrate Anticoagulation

Introduction: Peripheral venous access (PVA) is recommended as a first-line vascular approach for therapeutic plasmapheresis with centrifugation methods but not filtration, which usually requires high blood flow. We evaluated the feasibility, efficacy, and safety of double-filtration plasmapheresis (DFPP) with PVA, using ultrasound guidance and regional citrate anticoagulation (RCA), i.e., PVA-RCA-DFPP in patients undergoing chronic DFPP. Secondly, we assessed the number of central venous catheters (CVCs) avoided. Methods: A single-center retrospective study evaluated 22 adult patients on chronic DFPP to perform PVA-RCA-DFPP. They were classified into 3 groups: successful (i.e., completion of sessions with PVA), primary failure (i.e., no sessions completed), secondary failure (i.e., ≥1 session with PVA completed but secondary return with CVC or arteriovenous fistula). Results: Among the 22 patients included (64% men), 7 patients (32%) were classified as primary failures (2 patient refusals, 5 inadequate PVAs), 1 patient (5%) as a secondary failure (due to uncomfortable venipunctures), and 14 patients (64%) as successful. In the successful group including 12 patients treated for chronic inflammatory demyelinating polyneuropathy (CIDP) and 2 patients for familial hypercholesterolemia (FH) (2 patients), 116 sessions were performed, with a median treated plasma volume of 4.3 L [IQR 3.6–4.6] (45 mL/kg) for a median duration of 134 min [IQR 122–144], and a median blood flow of 94 mL/min [IQR 87–103]. For the CIDP group, 90% of sessions achieved a plasma volume >1 TPV, and for the FH group 91% of sessions achieved an LDLc reduction >60%. Eleven sessions out of 116 (9%) were interrupted, mostly due to PVA dysfunction (5/11) and circuit clotting (4/11). Session interruptions decreased significantly between each patient’s first and following sessions (29% to 7%, p = 0.009). Conclusion: Chronic PVA-RCA-DFPP can be performed safely and efficiently, avoiding the use of CVCs.

A comparative study of the effects of citrate and heparin anticoagulation on coagulation function and efficacy in children with septic shock undergoing continuous blood purification

To compare the effects of citrate and heparin anticoagulation on coagulation function and efficacy in children with septic shock undergoing continuous blood purification (CBP), and to provide guidance for CBP anticoagulation in children with septic shock. A case control study was conducted. Thirty-seven children with septic shock admitted to the pediatric intensive care unit (PICU) of the First Affiliated Hospital of Gannan Medical University from July 2019 to September 2022 were enrolled as the research subjects. The patients were divided into citrate local anticoagulation group and heparin systemic anticoagulation group according to different anticoagulation methods. The baseline data, the level of coagulation indicators [prothrombin time (PT), activated partial thromboplastin time (APTT), thrombin time (TT), fibrinogen (Fib), D-dimer] before treatment and 1 day after weaning from CBP, serum inflammatory mediators [interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), hypersensitivity C-reactive protein (hs-CRP), procalcitonin (PCT)], bleeding complications during CBP and 7-day mortality were collected. A total of 37 cases were enrolled finally, including 17 cases with citric acid local anticoagulation and 20 cases with heparin systemic anticoagulation. There was no statistically significant difference in general data such as gender, age, and body weight of children between the two groups. There were no statistically significant differences in baseline levels of coagulation indicators and inflammatory mediators before treatment of children between the two groups. One day after weaning from CBP, both groups showed varying degrees of improvement in coagulation indicators compared with those before treatment. Compared with before treatment, the PT of the heparin systemic anticoagulation group was significantly shortened after 1 day of weaning (s: 11.82±2.05 vs. 13.64±2.54), APTT and TT were significantly prolonged [APTT (s): 51.54±12.69 vs. 35.53±10.79, TT (s): 21.95±4.74 vs. 19.30±3.33], D-dimer level was significantly reduced (mg/L: 1.92±1.58 vs. 4.94±3.94), with statistically significant differences (all P < 0.05). While in the citrate local anticoagulation group, only APTT was significantly prolonged after treatment compared with that before treatment (s: 49.28±10.32 vs. 34.34±10.32, P < 0.05). There were no statistically significant differences in other coagulation indicators compared with before treatment. Compared with the citric acid local anticoagulation group, the PT of the heparin systemic anticoagulation group was significantly shortened after treatment (s: 11.82±2.05 vs. 13.61±3.05, P < 0.05), and the D-dimer level was significantly reduced (mg/L: 1.92±1.58 vs. 3.77±2.38, P < 0.01). The levels of inflammatory mediators in both groups were significantly reduced 1 day after CBP weaning compared with those before treatment [citric acid local anticoagulation group: hs-CRP (mg/L) was 12.53±5.44 vs. 22.65±7.27, PCT (μg/L) was 1.86±1.20 vs. 3.30±2.34, IL-6 (ng/L) was 148.48±34.83 vs. 202.32±48.62, TNF-α (ng/L) was 21.38±7.71 vs. 55.14±15.07; heparin systemic anticoagulation group: hs-CRP (mg/L) was 11.82±4.93 vs. 21.62±8.35, PCT (μg/L) was 1.90±1.08 vs. 3.18±1.97, IL-6 (ng/L) was 143.81±33.41 vs. 194.02±46.89, TNF-α (ng/L) was 22.44±8.17 vs. 56.17±16.92, all P < 0.05]. However, there was no statistically significant difference between the two groups (all P > 0.05). There was no statistically significant difference in bleeding complication during CBP and 7-day mortality in children between the citrate local anticoagulation group and the heparin systemic anticoagulation group (5.9% vs. 30.0%, 17.6% vs. 20.0%, both P > 0.05). Heparin for systemic anticoagulation and regional citrate anticoagulation can significantly reduce the levels of IL-6, TNF-α, hs-CRP and PCT in children with septic shock, and relieve inflammatory storm. Compared with citric acid local anticoagulation, heparin systemic anticoagulation can shorten the PT and reduce the level of D-dimer in children with septic shock, which may benefit in the prevention and treatment of disseminated intravascular coagulation (DIC).

Evaluation of Proenkephalin A 119–159 for liberation from renal replacement therapy: an external, multicenter pilot study in critically ill patients with acute kidney injury

IntroductionRecent evidence suggests an association of plasma Proenkephalin A 119–159 (penKid) with early and successful liberation from continuous renal replacement therapy (CRRT) in critically ill patients with acute kidney injury. However, these exploratory results are derived from a monocentric trial and therefore require external validation in a multicenter cohort.MethodsData and plasma samples from the “Effect of Regional Citrate Anticoagulation versus Systemic Heparin Anticoagulation During Continuous Kidney Replacement Therapy on Dialysis Filter Life Span and Mortality Among Critically Ill Patients With Acute Kidney Injury—A Randomized Clinical Trial” (RICH Trial) were used for this validation study. PenKid was measured in all plasma samples available at CRRT initiation and at day 3 of CRRT. Patients were categorized into low and high penKid groups with a cutoff at 100 pmol/l. Competing-risk time-to-event analyses were performed. Competing risk endpoints were successful and unsuccessful liberation from CRRT, the latter meaning death or initiation of a new RRT within one week of discontinuation of primary CRRT. Then penKid was compared to urinary output.ResultsLow pre-CRRT penKid levels at CRRT initiation were not associated with early and successful liberation from CRRT compared to patients with high pre-CRRT penKid levels [subdistribution hazard ratio (sHR) 1.01, 95% CI 0.73–1.40, p = 0.945]. However, the landmark analysis on day 3 of ongoing CRRT demonstrated an association between low penKid levels and successful liberation from CRRT (sHR 2.35, 95% CI 1.45–3.81, p < 0.001) and an association between high penKid levels and unsuccessful liberation (sHR 0.46, 95% CI 0.26–0.80, p = 0.007). High daily urinary output (> 436 ml/d) was even stronger associated with successful liberation (sHR 2.91, 95% CI 1.80–4.73, p < 0.001) compared to penKid.DiscussionThis study suggests that penKid may be a competent biomarker to monitor the recovery of kidney function during CRRT. This is in line with previous findings and investigated this concept in a multicenter cohort. Again, low penKid was associated with early and successful CRRT liberation, but was outperformed by high daily urinary output. The findings of this study now warrant further evaluation in prospective studies or a randomized controlled trial.Trial registration The RICH Trial was registered at clinicaltrials.gov: NCT02669589. Registered 01 February 2016.

Impact of increasing post-filter ionized calcium target on filter lifespan in renal replacement therapy with regional citrate anticoagulation: A before-and-after study

IntroductionRegional citrate anticoagulation (RCA) is the recommended method for anticoagulation in continuous renal replacement therapy (CRRT). However, the optimal post-filter ionized calcium (iCa) target level remains unclear. This study aims to assess the effect of increasing the post-filter iCa target level from 0.25–0.35 mmol/L to 0.30–0.40 mmol/L on filter lifespan until clotting during RCA-CRRT. MethodsThis before-and-after single-center study included patients who underwent RCA-CRRT sessions without systemic anticoagulation during two periods. The first period included patients with a post-filter iCa target between 0.25 and 0.35 mmol/L, while the second period included those with a target between 0.30 and 0.40 mmol/L. The primary outcome was filter lifespan until clotting. ResultsA total of 1037 CRRT sessions were analyzed, with 610 sessions in the first period and 427 sessions in the second period. After adjusting for confounding factors, there was no significant difference in filter lifespan until clotting between the two groups (hazard ratio, 1.020 [0.703; 1.481]; p = 0.92). ConclusionIncreasing the post-filter iCa target level from 0.25–0.35 mmol/L to 0.30–0.40 mmol/L during RCA-CRRT does not reduce filter lifespan until clotting and may decrease unnecessary citrate exposure. However, the optimal post-filter iCa target should be individualized according to the patient's clinical and biological status.

Thromboelastography and Traditional Coagulation Testing in Non-ICU-Admitted Patients with Acute Kidney Injury: An Observational Cohort Study

Introduction: This study aimed to elucidate the coagulation disorders in non-ICU patients with acute kidney injury (AKI) and their contribution to clotting-related outcomes of intermittent kidney replacement therapy (KRT). Methods: We included non-ICU-admitted patients with AKI requiring intermittent KRT, clinically having a risk of bleeding and against systemic anticoagulant use during KRT between April and December 2018. The premature termination of treatment due to circuit clotting was considered a poor outcome. We analyzed the characteristics of thromboelastography (TEG)-derived and traditional coagulation parameters and explored the potential-affecting factors. Results: In total, 64 patients were enrolled. Hypocoagulability was detected in 4.7%–15.6% of patients by a combination of the traditional parameters, i.e., prothrombin time (PT)/international normalized ratio, activated partial PT, and fibrinogen. No patient had hypocoagulability observed on TEG-derived reaction time; only 2.1%, 3.1%, and 10.9% of patients had hypocoagulability on TEG-derived kinetic time (K-time), α-angle, and maximum amplitude (MA), respectively, which were also platelet-related coagulation parameters, despite 37.5% of the cohort having thrombocytopenia. In contrast, hypercoagulability was more prevalent, involving 12.5%, 43.8%, 21.9%, and 48.4% of patients on TEG K-time, α-angle, MA, and coagulation index (CI), respectively, although thrombocytosis was only in 1.5% of the cohort. Patients with thrombocytopenia showed lower fibrinogen level (2.6 vs. 4.0 g/L, p = 0.00), α-angle (63.5° vs. 73.3°, p = 0.00), MA (53.5 vs. 66.1 mm, p = 0.00), and CI (1.8 vs. 3.6, p = 0.00) but higher thrombin time (17.8 vs. 16.2 s, p = 0.00) and K-time (2.0 vs. 1.2 min, p = 0.00) than those with a platelet count over 100 × 10⁹/L. 41 patients were treated with heparin-free protocol, and 23 were treated with regional citrate anticoagulation (RCA). The premature termination rate was 41.5% on heparin-free patients, while 8.7% of patients underwent an RCA protocol (p = 0.006). Heparin-free protocol was the strongest adverse factor to poor outcomes. A heparin-free subgroup analysis found that the circuit clotting risk was increased by 61.7% with a 10 × 10⁹/L elevation in platelet count (odds ratio [OR] = 1.617, p = 0.049) and decreased by 67.5% following a second increase of PT (OR = 0.325, p = 0.041). No significant correlation was found between TEG parameters and premature circuit clotting. Conclusions: Most non-ICU-admitted patients with AKI had normal-to-enhanced hemostasis and activated platelet function based on TEG results, as well as a high rate of premature circuit clotting when receiving heparin-free protocol despite thrombocytopenia. Further studies are needed to better determine the use of TEG in respect to management of anticoagulation and bleeding complications in AKI patients with KRT.

An individualized regional citrate anticoagulation protocol for hemodialysis: a real-world retrospective study.

To evaluate the safety and effectiveness of an individualized regional citrate anticoagulation (RCA) protocol for hemodialysis. In this single-center, retrospective study, blood coagulation in the extracorporeal circulation, adverse reactions, in vivo ionized calcium (iCa2+) concentrations, and the infusion dose of citrate during RCA in hemodialysis were observed in 98 patients from February 2021 to March 2022. A total of 98 patients underwent RCA during hemodialysis 362 times, and blood coagulation occurred in the extracorporeal circulation 29 times. Among the 29 cases of coagulation, most of the patients exhibited hypercoagulability, and among approximately 80% of the treatments, the deviation between the actual infusion rate of citrate in the extracorporeal circulation and the theoretical value was ± 10%. After hemodialysis, pH values and bicarbonate ion (HCO3-) levels were clearly improved, and online conductivity monitoring (OCM) values and blood coagulation scores in the extracorporeal circulation were identical to those measured in similar studies. An individualized RCA protocol for hemodialysis is safe, effective, simple, and inexpensive and can meet the needs of individualized treatment; therefore, its application is worthy of promotion.

Novel blood product transfusion regimen to prevent clotting and citrate accumulation during continuous renal replacement therapy with regional citrate anticoagulation in children.

Introduce a novel protocol to prevent clotting and citrate accumulation (CA) from blood product transfusion (BPT) during continuous renal replacement therapy (CRRT) with regional citrate anticoagulation (RCA) in children. We prospectively compared fresh frozen plasma (FFP) and platelet transfusions between the two BPT protocols, direct transfusion protocol (DTP) and partial replacement of citrate transfusion protocol (PRCTP), in terms of the risks of clotting, citric accumulation (CA), and hypocalcemia. For DTP, blood products were directly transfused without any adjustment to the original RCA-CRRT regimen. For PRCTP, the blood products were infused into the CRRT circulation near the sodium citrate infusion point, and the dosage of 4% sodium citrate was reduced depending on the dosage of sodium citrate in the blood products. Basic information and clinical data were recorded for all children. Heart rate, blood pressure, ionized calcium (iCa) and various pressure parameters were recorded before, during and after BPT, as well as coagulation indicators, electrolytes, and blood cell counts before and after BPT. Twenty-six children received 44 PRCTPs and 15 children received 20 DTPs. The two groups had similar in vitro ionized calcium (iCa) concentrations (PRCTP: 0.33 ± 0.06 mmol/L, DTP: 0.31 ± 0.04 mmol/L), total filter lifespan (PRCTP: 49.33 ± 18.58, DTP: 50.65 ± 13.57 h), and filter lifespan after BPT (PRCTP: 25.31 ± 13.87, DTP: 23.39 ± 11.34 h). There was no visible filter clotting during BPT in any of the two groups. The two groups had no significant differences in arterial pressure, venous pressure, and transmembrane pressure before, during, or after BPT. Neither treatment led to significant decreases in WBC, RBC, or hemoglobin. The platelet transfusion group and the FFP group each had no significant decrease in platelets, and no significant increases in PT, APTT, and D-dimer. The most clinically significant changes were in the DTP group, in which the ratio of total calcium to ionized calcium (T/iCa) increased from 2.06 ± 0.19 to 2.52 ± 0.35, the percentage of patients with T/iCa above 2.5 increased from 5.0% to 45%, and the level of in vivo iCa increased from 1.02 ± 0.11 to 1.06 ± 0.09 mmol/L (all p < 0.05). Changes in these three indicators were not significant in the PRCTP group. Neither protocol was associated with filter clotting during RCA-CRRT. However, PRCTP was superior to DTP because it did not increase the risk of CA and hypocalcemia.

#5633 USE OF HEPARIN GRAFTED DIALYZER (EVODIAL) FOR HEMODIALYSIS IN PATIENTS WITH HIGH RISK OF BLEEDING: A SINGLE CENTER EXPERIENCE

Abstract Background and Aims During hemodialysis exposure of the blood to the dialysis membrane and the tubing system can activate blood cells and promote clotting activation. So usually, some form of anticoagulation, most frequently heparin, is used to prevent blood coagulation. However, there are patients with increased risk for bleeding (patients with active bleeding, major surgery in past 72 hours, severe trombocytopenia) where use of heparin free regime is mandatory. Evodial dialyzer (Gambro-Hospal, France) [1] contains a heparin-grafted membrane aiming to provide a system with a low thrombogenicity that can be used without or with low dose heparin in order to reduce the patients' bleeding risk. As high-quality evidence of the optimal choice of anticoagulation in these patients is limited we wanted to show our experience with the use of Evodial dialyzer. Method During 12 months 106 dialysis sessions in 59 patients were performed. Reasons for using Evodial : active bleeding, hematological conditions, complications of vascular access. Changes in the dialyzer or the blood lines, or any aditional interventions were examined. Results Low dose unfractionated heparin (1250 IE total) was used in 10 (9,4%) sessions, and it was added in 15 (14%) more sessions because of problems with the coagulation. In 4 (2,8%) sessions we had to terminate dialysis because of clotting. Conclusion Heparin grafted dialyzers can be safely used in patients with high risk for bleeding. Although results are worse than the ones reported in literature [2] where regional citrate anticoagulation (RCA) is used, it can be reasonable alternative when RCA is unavailable.

#6376 TREATMENT OF DABIGATRAN INTOXICATION IN CRITICALLY ILL PATIENTS WITH ACUTE KIDNEY INJURY: THE ROLE OF SUSTAINED LOW-EFFICIENCY DIALYSIS

Abstract Background and Aims Dabigatran, a direct thrombin inhibitor, is a commonly used direct oral anticoagulant (DOAC) prescribed for non-valvular atrial fibrillation. Despite its benefits in term of safety/effectiveness along with the possibility to treat patients who were ineligible for vitamin K inhibitors (VKAs), a great degree of attention is required in elderly patients with multiple comorbidities. Notably, dabigatran mainly undergoes renal elimination, and dose adjustment is recommended in patients with Chronic Kidney Disease (CKD). In this regard, the onset of an abrupt decrease of kidney function may further affect dabigatran pharmacokinetic profile, increasing the risk of acute intoxication. Idarucizumab is the approved antagonist in the case of dabigatran-associated major bleeding or concomitant need of urgent surgery, but its clinical use is limited by the lack of data in patients with Acute Kidney Injury (AKI). Given the dabigatran PK parameters (low MW, low Vd, negligible protein binding), the early start of Extracorporeal Kidney Replacement Therapy (EKRT) may represent the optimal reversal strategy. We present a case series of three critically ill patients with AKI and dabigatran overdose treated with Sustained Low-Efficiency Dialysis (SLED). Methods Three critically ill patients (Table 1) were admitted to the Renal Intensive Care Unit (ICU) for stage 3 AKI and intercurrent dabigatran intoxication. SLED sessions with Regional Citrate Anticoagulation (RCA) were prescribed with SURDIAL X machine, ELISIO-21M filter (Nipro Co., Osaka, Japan) [blood flow rate 200 mL/min, dialysis fluid rate 300 mL/min; citrate flow rate 350 mL/h (ACD Fresenius Kabi, Italia)]. Dabigatran plasma levels (dilute thrombin time, dTT) along with coagulation parameters were monitored before, during and after SLED session. Results A rapid and sustained decreased of plasma dabigatran level was observed in each patient in course of SLED sessions. No clinically relevant post-treatment rebound was reported (Figure 1). Conclusions SLED meets the requirements to be a viable reversal anticoagulation option in the context of dabigatran overdose. Indeed, it efficiently provides dabigatran removal, by reaching a safe plasma concentration within the first hours and avoiding significant rebound effect.

#3123 INCREASING THE USE OF REGIONAL CITRATE ANTICOAGULATION FOR CKRT IN A LARGE TERTIARY CENTER: A QUALITY IMPROVEMENT PROJECT

Abstract Background and Aims To maintain Continuous Kidney Replacement Therapy (CKRT) circuit patency, KDIGO recommends Regional Citrate Anticoagulation (RCA) as the first-line anticoagulation strategy. In a randomized controlled trial, RCA was associated with increased filter life, reduced circuit downtime, and reduced bleeding, as compared with heparin anticoagulation [1]. RCA-CKRT uptake in our institution, a 1800-bed tertiary center with seven intensive care units (ICU), was low at only 10% of all CKRT sessions. We conducted a Quality Improvement project to increase the uptake of RCA-CKRT in medical and surgical intensive care units in our institution. Method Following established Quality Improvement methodology, we delineated a process map and performed a root-cause analysis. Multiple plan-do-study-act (PDSA) cycles were conducted. A bespoke CKRT audit dashboard was created to automatically compile electronic CKRT prescription records and circuit monitoring data. The primary outcome measure, the percentage of all CKRT sessions that utilise RCA, was monitored monthly. Qualitative and quantitative feedback was monitored. Results Problem analysis (Figure 1) identified that the top root causes contributing to low RCA-CKRT uptake rate were (1) renal physicians defaulting to ‘old habits’ of non-RCA CKRT, (2) nursing staff having inadequate experience and concerns of increased workload, (3) ICU team being uncomfortable with RCA-CKRT, especially fear of citrate toxicity. Multiple PDSA cycles were conducted. In PDSA cycle 1, inclusion and exclusion criteria for default RCA use were standardized. A poster was created to set out these criteria, along with a visual guide explaining how RCA works, and how to identify citrate toxicity. The poster was designed to be eye-catching and easy to understand for non-renal physicians, and was placed prominently in ICU and renal work areas. PDSA cycles 2-4 were educational efforts, including a peer review learning for the renal department, incorporating RCA into ICU resident didactic teaching, and an RCA refresher course for ICU nurses. Through these four PDSA cycles, all three top root causes identified were addressed in turn. Continuous feedback was sought from all stakeholders and acted on in a timely manner. For example, it was identified that some prescribers and nursing staff had the misconception that switching from non-RCA to RCA-CKRT would require changing the entire filter circuit, leading to reluctance to switch to RCA once a CKRT circuit was running. A clarification was promulgated and added to the poster. Over a 12-month period, the percentage of all CKRT sessions utilizing RCA increased from a baseline of 10.5% ± 7.7% (mean ± SD; median 9.8%) to 22.5% ± 14.6% (median 21.5%; p = 0.022) (Figure 2). This included a 3-month period after PDSA cycle 1 during which supplies of RCA-CKRT fluid were disrupted due to COVID-19 supply chain issues. Excluding the months of supply disruption, the uptake of RCA-CKRT would have been 25.3% ± 15.8% (median 25.0%). Conclusion A quality improvement project successfully increased the uptake of RCA-CKRT from 10.5% to 22.5% in a complex tertiary care setting. Understanding key barriers at each stage of a complex process, availability of real-time audit data, and attention to stakeholder feedback were key factors that enabled successful change. Unexpected events (in this case a supply chain disruption) may threaten a loss of momentum for change, but can be overcome with continual stakeholder engagement and additive PDSA cycles.

Factors affecting continuous renal replacement therapy duration in critically ill patients: A retrospective study.

This study aimed to analyze the factors affecting continuous renal replacement therapy (CRRT) duration in critically ill patients and provide a reference for clinical treatment. We divided patients into regional citrate anti-coagulation (RCA) and low-molecular-weight-heparin (LMWH) groups according to the anti-coagulation method and collected the relevant data, to analyze the factors associated with CRRT time. Compared with the LMWH group, the RCA group had a longer mean treatment time (55.36 ± 22.57 vs. 37.65 ± 27.09 h, p < 0.001), lower transmembrane pressure, and lower filter pressure, regardless of vascular access site. Multivariable linear regression analysis showed a significant correlation between anti-coagulation patterns, filter pressure at CRRT discontinuation, nurses' level of intensive care unit experience, pre-machine fibrinogen level, and CRRT time. Anti-coagulation is the most important factor affecting CRRT duration. Filter pressure, nurses' level of intensive care unit experience, and fibrinogen level also affecting CRRT duration.

Anticoagulation options for continuous renal replacement therapy in critically ill patients: a systematic review and network meta-analysis of randomized controlled trials

BackgroundContinuous renal replacement therapy (CRRT) is a widely used standard therapy for critically ill patients with acute kidney injury (AKI). Despite its effectiveness, treatment is often interrupted due to clot formation in the extracorporeal circuits. Anticoagulation is a crucial strategy for preventing extracorporeal circuit clotting during CRRT. While various anticoagulation options are available, there were still no studies synthetically comparing the efficacy and safety of these anticoagulation options.MethodsElectronic databases (PubMed, Embase, Web of Science, and the Cochrane database) were searched from inception to October 31, 2022. All randomized controlled trials (RCTs) that examined the following outcomes were included: filter lifespan, all-cause mortality, length of stay, duration of CRRT, recovery of kidney function, adverse events and costs.ResultsThirty-seven RCTs from 38 articles, comprising 2648 participants with 14 comparisons, were included in this network meta-analysis (NMA). Unfractionated heparin (UFH) and regional citrate anticoagulation (RCA) are the most frequently used anticoagulants. Compared to UFH, RCA was found to be more effective in prolonging filter lifespan (MD 12.0, 95% CI 3.8 to 20.2) and reducing the risk of bleeding. Regional-UFH plus Prostaglandin I2 (Regional-UFH + PGI2) appeared to outperform RCA (MD 37.0, 95% CI 12.0 to 62.0), LMWH (MD 41.3, 95% CI 15.6 to 67.0), and other evaluated anticoagulation options in prolonging filter lifespan. However, only a single included RCT with 46 participants had evaluated Regional-UFH + PGI2. No statistically significant difference was observed in terms of length of ICU stay, all-cause mortality, duration of CRRT, recovery of kidney function, and adverse events among most evaluated anticoagulation options.ConclusionsCompared to UFH, RCA is the preferred anticoagulant for critically ill patients requiring CRRT. The SUCRA analysis and forest plot of Regional-UFH + PGI2 are limited, as only a single study was included. Additional high-quality studies are necessary before any recommendation of Regional-UFH + PGI2. Further larger high-quality RCTs are desirable to strengthen the evidence on the best choice of anticoagulation options to reduce all-cause mortality and adverse events and promote the recovery of kidney function.Trial registration The protocol of this network meta-analysis was registered on PROSPERO (CRD42022360263). Registered 26 September 2022.

Non-anticoagulant factors affecting coagulation in the extracorporeal circulation circuit and the development of an individualized regional citrate anticoagulation protocol for hemodialysis: A real-world retrospective study.

To investigate non-anticoagulant factors that affect blood coagulation in the extracorporeal circulation (ECC) circuit of regional citrate anticoagulation (RCA) protocol for hemodialysis (HD). The clinical characteristics of patients undergoing an individualized RCA protocol for HD between February 2021 and March 2022 were collected; Coagulation scores, pressures in various parts of the ECC circuit, the incidence of coagulation, and citrate concentrations in the ECC circuit during treatment were determined, and non-anticoagulant factors affecting coagulation in the ECC circuit were analyzed. The lowest clotting rate was 2.8% in patients with arteriovenous fistula in various vascular access. Patients on Fresenius dialysis had a lower rate of clotting in the cardiopulmonary bypass line than patients on other brands of dialyzer. Low-throughput dialyzers are less likely to clot than high-throughput dialyzers. There are significant differences in the incidence of coagulation among different nurses during citrate anticoagulant hemodialysis. In the process of citrate anticoagulant hemodialysis, non-anticoagulant factors such as coagulation status, vascular access, dialyzer selection, and operator quality will affect the anticoagulant effect.

Management of regional citrate anticoagulation for continuous renal replacement therapy: guideline recommendations from Chinese emergency medical doctor consensus

Continuous renal replacement therapy (CRRT) is widely used for treating critically-ill patients in the emergency department in China. Anticoagulant therapy is needed to prevent clotting in the extracorporeal circulation during CRRT. Regional citrate anticoagulation (RCA) has been shown to potentially be safer and more effective and is now recommended as the preferred anticoagulant method for CRRT. However, there is still a lack of unified standards for RCA management in the world, and there are many problems in using this method in clinical practice. The Emergency Medical Doctor Branch of the Chinese Medical Doctor Association (CMDA) organized a panel of domestic emergency medicine experts and international experts of CRRT to discuss RCA-related issues, including the advantages and disadvantages of RCA in CRRT anticoagulation, the principle of RCA, parameter settings for RCA, monitoring of RCA (mainly metabolic acid–base disorders), and special issues during RCA. Based on the latest available research evidence as well as the paneled experts’ clinical experience, considering the generalizability, suitability, and potential resource utilization, while also balancing clinical advantages and disadvantages, a total of 16 guideline recommendations were formed from the experts’ consensus.

A simplified protocol of regional citrate anticoagulation with phosphate-containing solutions in infants and children treated with continuous kidney replacement therapy.

Regional citrate anticoagulation (RCA) is the preferred modality of anticoagulation used in continuous kidney replacement therapy (CKRT) in adults and less extensively in children. Potential metabolic complications limit widespread use in infants, neonates, and in children with liver failure. We report our experience with a simplified protocol in 50 critically ill children, infants, and neonates, some of them with liver failure, with commercially available solutions containing phosphorous and higher concentration of potassium and magnesium. RCA allowed attainment of a mean filter lifetime of 54.5 ± 18.2h, 42.5% of circuits lasted more than 70h, and scheduled change was the most frequent cause of CKRT interruption. Patient Ca++ and circuit Ca++ were maintained in the target range with mean values of 1.15 ± 0.13mmol/l and 0.38 ± 0.07mmol/l, respectively. No session had to be stopped because of metabolic complications. The most frequent complications were hyponatremia, hypomagnesemia, and metabolic acidosis mostly related to primary disease and critical illness. No session had to be stopped because of citrate accumulation (CA). Transitory CA occurred in 6 patients and was managed without requiring RCA interruption. No patients with liver failure presented CA episodes. In our experience, RCA with commercially available solutions was easily applied and managed in critically ill children, even in patients with low weight or with liver failure. Solutions containing phosphate and higher concentrations of magnesium and potassium allowed reduction of metabolic derangement during CKRT. Prolonged filter life was ensured with no detrimental effects on patients and reduced staff workload. A higher resolution version of the Graphical abstract is available as Supplementary information.