Safe and effective anticoagulation is the key to successful blood purification. Compared with traditional systemic anticoagulation, regional citrate anticoagulation (RCA) has the advantages of prolonging the life of extracorporeal circulation and reducing bleeding complications. However, the complex protocol, the disorder of electrolyte and acid-base status and the accumulation risk in special populations have dissuaded many clinicians. This review starts with the clinical monitoring of RCA, then analyzes the causes and treatments of complications. The risk assessments in special populations were also introduced in order to the widely promotion of RCA in critically ill patients.
Citation： ZHANG Qi, DING Feng. Clinical monitoring and risk assessment of regional citrate anticoagulation in continuous renal replacement therapy. West China Medical Journal, 2022, 37(7): 1088-1093. doi: 10.7507/1002-0179.202205151 Copy
| 1. | Liu C, Mao Z, Kang H, et al. Regional citrate versus heparin anticoagulation for continuous renal replacement therapy in critically ill patients: a meta-analysis with trial sequential analysis of randomized controlled trials. Crit Care, 2016, 20(1): 144. |
| 2. | Zarbock A, Küllmar M, Kindgen-Milles D, et al. Effect of regional citrate anticoagulation vs 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. JAMA, 2020, 324(16): 1629-1639. |
| 3. | Section 5: dialysis interventions for treatment of AKI. Kidney Int Suppl (2011), 2012, 2(1): 89-115. |
| 4. | Kindgen-Milles D, Brandenburger T, Dimski T. Regional citrate anticoagulation for continuous renal replacement therapy. Curr Opin Crit Care, 2018, 24(6): 450-454. |
| 5. | Davenport A, Tolwani A. Citrate anticoagulation for continuous renal replacement therapy (CRRT) in patients with acute kidney injury admitted to the intensive care unit. NDT Plus, 2009, 2(6): 439-447. |
| 6. | Morgan DJ, Ho KM. Profound hypocalcaemia in a patient being anticoagulated with citrate for continuous renal replacement therapy. Anaesthesia, 2009, 64(12): 1363-1366. |
| 7. | Morabito S, Pistolesi V, Tritapepe L, et al. Regional citrate anticoagulation for RRTs in critically ill patients with AKI. Clin J Am Soc Nephrol, 2014, 9(12): 2173-2188. |
| 8. | Wang PL, Meyer MM, Orloff SL, et al. Bone resorption and “relative” immobilization hypercalcemia with prolonged continuous renal replacement therapy and citrate anticoagulation. Am J Kidney Dis, 2004, 44(6): 1110-1114. |
| 9. | Raimundo M, Crichton S, Lei K, et al. Maintaining normal levels of ionized calcium during citrate-based renal replacement therapy is associated with stable parathyroid hormone levels. Nephron Clin Pract, 2013, 124(1/2): 124-131. |
| 10. | Degraeve A, Danse E, Laterre PF, et al. Regional citrate anticoagulation and influence of recirculation on ionized calcium levels in the circuit. J Artif Organs, 2019, 22(4): 341-344. |
| 11. | Wang F, Dai M, Zhao Y, et al. Reliability of monitoring acid-base and electrolyte parameters through circuit lines during regional citrate anticoagulation-continuous renal replacement therapy. Nurs Crit Care. (2020-10-21)[2021-07-19]. https://onlinelibrary.wiley.com/doi/epdf/10.1111/nicc.12696. |
| 12. | Warnar C, Faber E, Katinakis PA, et al. Electrolyte monitoring during regional citrate anticoagulation in continuous renal replacement therapy. J Clin Monit Comput, 2022, 36(3): 871-877. |
| 13. | Gupta M, Wadhwa NK, Bukovsky R. Regional citrate anticoagulation for continuous venovenous hemodiafiltration using calcium-containing dialysate. Am J Kidney Dis, 2004, 43(1): 67-73. |
| 14. | Kirwan CJ, Hutchison R, Ghabina S, et al. Implementation of a simplified regional citrate anticoagulation protocol for post-dilution continuous hemofiltration using a bicarbonate buffered, calcium containing replacement solution. Blood Purif, 2016, 42(4): 349-355. |
| 15. | Kutsogiannis DJ, Gibney RT, Stollery D, et al. Regional citrate versus systemic heparin anticoagulation for continuous renal replacement in critically ill patients. Kidney Int, 2005, 67(6): 2361-2367. |
| 16. | Oudemans-van Straaten HM, Bosman RJ, Koopmans M, et al. Citrate anticoagulation for continuous venovenous hemofiltration. Crit Care Med, 2009, 37(2): 545-552. |
| 17. | Brain MJ, Roodenburg OS, McNeil J. Comparison of pre-filter and post-filter ionised calcium monitoring in continuous veno-venous hemodiafiltration (CVVHD-F) with citrate anti-coagulation. PLoS One, 2017, 12(12): e0189745. |
| 18. | Zhang L, Liao Y, Xiang J, et al. Simplified regional citrate anticoagulation using a calcium-containing replacement solution for continuous venovenous hemofiltration. J Artif Organs, 2013, 16(2): 185-192. |
| 19. | Buturovic-Ponikvar J, Cerne S, Gubensek J, et al. Regional citrate anticoagulation for hemodialysis: calcium-free vs. calcium containing dialysate - a randomized trial. Int J Artif Organs, 2008, 31(5): 418-424. |
| 20. | Schwarzer P, Kuhn SO, Stracke S, et al. Discrepant post filter ionized calcium concentrations by common blood gas analyzers in CRRT using regional citrate anticoagulation. Crit Care, 2015, 19(1): 321. |
| 21. | D’Orazio P, Visnick H, Balasubramanian S. Accuracy of commercial blood gas analyzers for monitoring ionized calcium at low concentrations. Clin Chim Acta, 2016, 461: 34-40. |
| 22. | Feldkamp T, Weiler N, Marx M, et al. Critical deviations of ionized calcium measurements when using blood gas analyzers to monitor citrate dialysis. Clin Lab, 2016, 62(10): 2025-2031. |
| 23. | Zhang Q, Zhuang F, Fan Q, et al. The possibility of using effluent ionized calcium to assess regional citrate anticoagulation in continuous renal replacement therapy. Int J Artif Organs, 2020, 43(6): 379-384. |
| 24. | Schneider AG, Journois D, Rimmelé T. Complications of regional citrate anticoagulation: accumulation or overload?. Crit Care, 2017, 21(1): 281. |
| 25. | Bakker AJ, Boerma EC, Keidel H, et al. Detection of citrate overdose in critically ill patients on citrate-anticoagulated venovenous haemofiltration: use of ionised and total/ionised calcium. Clin Chem Lab Med, 2006, 44(8): 962-966. |
| 26. | Anstey CM, Venkatesh B. A comparison of the commonly used surrogate markers for citrate accumulation and toxicity during continuous renal replacement therapy with regional citrate anticoagulation. Blood Purif, 2022: 1-9. |
| 27. | Zheng Y, Zhuang F, Zhu Q, et al. Albumin-corrected total/ionized calcium ratio is not superior to total/ionized calcium ratio as an indicator of citrate accumulation. Int J Artif Organs, 2017, 40(11): 602-606. |
| 28. | Zhao L, Ma F, Yu Y, et al. Regional citrate anticoagulation versus no-anticoagulation for continuous venovenous hemofiltration in acute severe hypernatremia patients with increased bleeding risk: a retrospective cohort study. Blood Purif, 2020, 49(1/2): 44-54. |
| 29. | Di Mario F, Regolisti G, Greco P, et al. Prevention of hypomagnesemia in critically ill patients with acute kidney injury on continuous kidney replacement therapy: the role of early supplementation and close monitoring. J Nephrol, 2021, 34(4): 1271-1279. |
| 30. | Brain M, Anderson M, Parkes S, et al. Magnesium flux during continuous venovenous haemodiafiltration with heparin and citrate anticoagulation. Crit Care Resusc, 2012, 14(4): 274-282. |
| 31. | Zakharchenko M, Leden P, Rulíšek J, et al. Ionized magnesium and regional citrate anticoagulation for continuous renal replacement therapy. Blood Purif, 2016, 41(1/2/3): 41-47. |
| 32. | Zakharchenko M, Los F, Brodska H, et al. The effects of high level magnesium dialysis/substitution fluid on magnesium homeostasis under regional citrate anticoagulation in critically ill. PLoS One, 2016, 11(7): e0158179. |
| 33. | Jeffrey YH, Hoi-Ping S, Kit Hung AL, et al. Experiences with continuous venovenous hemofiltration using 18 mmol/L predilution citrate anticoagulation and a phosphate containing replacement solution. Indian J Crit Care Med, 2017, 21(1): 11-16. |
| 34. | Adrogué HJ, Madias NE. Assessing acid-base status: physiologic versus physicochemical approach. Am J Kidney Dis, 2016, 68(5): 793-802. |
| 35. | Nagaoka D, Nassar Junior AP, Maciel AT, et al. The use of sodium-chloride difference and chloride-sodium ratio as strong ion difference surrogates in the evaluation of metabolic acidosis in critically ill patients. J Crit Care, 2010, 25(3): 525-531. |
| 36. | Mehta RL, McDonald BR, Aguilar MM, et al. Regional citrate anticoagulation for continuous arteriovenous hemodialysis in critically ill patients. Kidney Int, 1990, 38(5): 976-981. |
| 37. | Hetzel GR, Taskaya G, Sucker C, et al. Citrate plasma levels in patients under regional anticoagulation in continuous venovenous hemofiltration. Am J Kidney Dis, 2006, 48(5): 806-811. |
| 38. | Schultheiβ C, Saugel B, Phillip V, et al. Continuous venovenous hemodialysis with regional citrate anticoagulation in patients with liver failure: a prospective observational study. Crit Care, 2012, 16(4): R162. |
| 39. | Tan JN, Haroon SWP, Mukhopadhyay A, et al. Hyperlactatemia predicts citrate intolerance with regional citrate anticoagulation during continuous renal replacement therapy. J Intensive Care Med, 2019, 34(5): 418-425. |
| 40. | Zhang W, Bai M, Yu Y, et al. Safety and efficacy of regional citrate anticoagulation for continuous renal replacement therapy in liver failure patients: a systematic review and meta-analysis. Crit Care, 2019, 23(1): 22. |
| 41. | Lahmer T, Messer M, Rasch S, et al. Sustained low-efficiency dialysis with regional citrate anticoagulation in medical intensive care unit patients with liver failure: a prospective study. J Crit Care, 2015, 30(5): 1096-1100. |
| 42. | Slowinski T, Morgera S, Joannidis M, et al. Safety and efficacy of regional citrate anticoagulation in continuous venovenous hemodialysis in the presence of liver failure: the liver citrate anticoagulation threshold (L-CAT) observational study. Crit Care, 2015, 19: 349. |
| 43. | Klingele M, Stadler T, Fliser D, et al. Long-term continuous renal replacement therapy and anticoagulation with citrate in critically ill patients with severe liver dysfunction. Crit Care, 2017, 21(1): 294. |
| 44. | Faybik P, Hetz H, Mitterer G, et al. Regional citrate anticoagulation in patients with liver failure supported by a molecular adsorbent recirculating system. Crit Care Med, 2011, 39(2): 273-279. |
| 45. | Meijers B, Laleman W, Vermeersch P, et al. A prospective randomized open-label crossover trial of regional citrate anticoagulation vs. anticoagulation free liver dialysis by the molecular adsorbents recirculating system. Crit Care, 2012, 16(1): R20. |
| 46. | Saner FH, Treckmann JW, Geis A, et al. Efficacy and safety of regional citrate anticoagulation in liver transplant patients requiring post-operative renal replacement therapy. Nephrol Dial Transplant, 2012, 27(4): 1651-1657. |
| 47. | Khadzhynov D, Schelter C, Lieker I, et al. Incidence and outcome of metabolic disarrangements consistent with citrate accumulation in critically ill patients undergoing continuous venovenous hemodialysis with regional citrate anticoagulation. J Crit Care, 2014, 29(2): 265-271. |
| 48. | Li L, Bai M, Yu Y, et al. Regional citrate anticoagulation vs no-anticoagulation for CRRT in hyperlactatemia patients with increased bleeding risk: a retrospective cohort study. Semin Dial, 2021, 34(3): 209-217. |
| 49. | Li L, Bai M, Zhang W, et al. Regional citrate anticoagulation versus low molecular weight heparin for CRRT in hyperlactatemia patients: a retrospective case-control study. Int J Artif Organs, 2022, 45(4): 343-350. |
| 50. | Khadzhynov D, Dahlinger A, Schelter C, et al. Hyperlactatemia, lactate kinetics and prediction of citrate accumulation in critically ill patients undergoing continuous renal replacement therapy with regional citrate anticoagulation. Crit Care Med, 2017, 45(9): e941-e946. |
| 51. | Boer W, Van Tornout M, Vander Laenen M, et al. Catheter port reversal in citrate continuous veno-venous hemofiltration. Kidney Int Rep, 2021, 6(11): 2775-2781. |
- 1. Liu C, Mao Z, Kang H, et al. Regional citrate versus heparin anticoagulation for continuous renal replacement therapy in critically ill patients: a meta-analysis with trial sequential analysis of randomized controlled trials. Crit Care, 2016, 20(1): 144.
- 2. Zarbock A, Küllmar M, Kindgen-Milles D, et al. Effect of regional citrate anticoagulation vs 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. JAMA, 2020, 324(16): 1629-1639.
- 3. Section 5: dialysis interventions for treatment of AKI. Kidney Int Suppl (2011), 2012, 2(1): 89-115.
- 4. Kindgen-Milles D, Brandenburger T, Dimski T. Regional citrate anticoagulation for continuous renal replacement therapy. Curr Opin Crit Care, 2018, 24(6): 450-454.
- 5. Davenport A, Tolwani A. Citrate anticoagulation for continuous renal replacement therapy (CRRT) in patients with acute kidney injury admitted to the intensive care unit. NDT Plus, 2009, 2(6): 439-447.
- 6. Morgan DJ, Ho KM. Profound hypocalcaemia in a patient being anticoagulated with citrate for continuous renal replacement therapy. Anaesthesia, 2009, 64(12): 1363-1366.
- 7. Morabito S, Pistolesi V, Tritapepe L, et al. Regional citrate anticoagulation for RRTs in critically ill patients with AKI. Clin J Am Soc Nephrol, 2014, 9(12): 2173-2188.
- 8. Wang PL, Meyer MM, Orloff SL, et al. Bone resorption and “relative” immobilization hypercalcemia with prolonged continuous renal replacement therapy and citrate anticoagulation. Am J Kidney Dis, 2004, 44(6): 1110-1114.
- 9. Raimundo M, Crichton S, Lei K, et al. Maintaining normal levels of ionized calcium during citrate-based renal replacement therapy is associated with stable parathyroid hormone levels. Nephron Clin Pract, 2013, 124(1/2): 124-131.
- 10. Degraeve A, Danse E, Laterre PF, et al. Regional citrate anticoagulation and influence of recirculation on ionized calcium levels in the circuit. J Artif Organs, 2019, 22(4): 341-344.
- 11. Wang F, Dai M, Zhao Y, et al. Reliability of monitoring acid-base and electrolyte parameters through circuit lines during regional citrate anticoagulation-continuous renal replacement therapy. Nurs Crit Care. (2020-10-21)[2021-07-19]. https://onlinelibrary.wiley.com/doi/epdf/10.1111/nicc.12696.
- 12. Warnar C, Faber E, Katinakis PA, et al. Electrolyte monitoring during regional citrate anticoagulation in continuous renal replacement therapy. J Clin Monit Comput, 2022, 36(3): 871-877.
- 13. Gupta M, Wadhwa NK, Bukovsky R. Regional citrate anticoagulation for continuous venovenous hemodiafiltration using calcium-containing dialysate. Am J Kidney Dis, 2004, 43(1): 67-73.
- 14. Kirwan CJ, Hutchison R, Ghabina S, et al. Implementation of a simplified regional citrate anticoagulation protocol for post-dilution continuous hemofiltration using a bicarbonate buffered, calcium containing replacement solution. Blood Purif, 2016, 42(4): 349-355.
- 15. Kutsogiannis DJ, Gibney RT, Stollery D, et al. Regional citrate versus systemic heparin anticoagulation for continuous renal replacement in critically ill patients. Kidney Int, 2005, 67(6): 2361-2367.
- 16. Oudemans-van Straaten HM, Bosman RJ, Koopmans M, et al. Citrate anticoagulation for continuous venovenous hemofiltration. Crit Care Med, 2009, 37(2): 545-552.
- 17. Brain MJ, Roodenburg OS, McNeil J. Comparison of pre-filter and post-filter ionised calcium monitoring in continuous veno-venous hemodiafiltration (CVVHD-F) with citrate anti-coagulation. PLoS One, 2017, 12(12): e0189745.
- 18. Zhang L, Liao Y, Xiang J, et al. Simplified regional citrate anticoagulation using a calcium-containing replacement solution for continuous venovenous hemofiltration. J Artif Organs, 2013, 16(2): 185-192.
- 19. Buturovic-Ponikvar J, Cerne S, Gubensek J, et al. Regional citrate anticoagulation for hemodialysis: calcium-free vs. calcium containing dialysate - a randomized trial. Int J Artif Organs, 2008, 31(5): 418-424.
- 20. Schwarzer P, Kuhn SO, Stracke S, et al. Discrepant post filter ionized calcium concentrations by common blood gas analyzers in CRRT using regional citrate anticoagulation. Crit Care, 2015, 19(1): 321.
- 21. D’Orazio P, Visnick H, Balasubramanian S. Accuracy of commercial blood gas analyzers for monitoring ionized calcium at low concentrations. Clin Chim Acta, 2016, 461: 34-40.
- 22. Feldkamp T, Weiler N, Marx M, et al. Critical deviations of ionized calcium measurements when using blood gas analyzers to monitor citrate dialysis. Clin Lab, 2016, 62(10): 2025-2031.
- 23. Zhang Q, Zhuang F, Fan Q, et al. The possibility of using effluent ionized calcium to assess regional citrate anticoagulation in continuous renal replacement therapy. Int J Artif Organs, 2020, 43(6): 379-384.
- 24. Schneider AG, Journois D, Rimmelé T. Complications of regional citrate anticoagulation: accumulation or overload?. Crit Care, 2017, 21(1): 281.
- 25. Bakker AJ, Boerma EC, Keidel H, et al. Detection of citrate overdose in critically ill patients on citrate-anticoagulated venovenous haemofiltration: use of ionised and total/ionised calcium. Clin Chem Lab Med, 2006, 44(8): 962-966.
- 26. Anstey CM, Venkatesh B. A comparison of the commonly used surrogate markers for citrate accumulation and toxicity during continuous renal replacement therapy with regional citrate anticoagulation. Blood Purif, 2022: 1-9.
- 27. Zheng Y, Zhuang F, Zhu Q, et al. Albumin-corrected total/ionized calcium ratio is not superior to total/ionized calcium ratio as an indicator of citrate accumulation. Int J Artif Organs, 2017, 40(11): 602-606.
- 28. Zhao L, Ma F, Yu Y, et al. Regional citrate anticoagulation versus no-anticoagulation for continuous venovenous hemofiltration in acute severe hypernatremia patients with increased bleeding risk: a retrospective cohort study. Blood Purif, 2020, 49(1/2): 44-54.
- 29. Di Mario F, Regolisti G, Greco P, et al. Prevention of hypomagnesemia in critically ill patients with acute kidney injury on continuous kidney replacement therapy: the role of early supplementation and close monitoring. J Nephrol, 2021, 34(4): 1271-1279.
- 30. Brain M, Anderson M, Parkes S, et al. Magnesium flux during continuous venovenous haemodiafiltration with heparin and citrate anticoagulation. Crit Care Resusc, 2012, 14(4): 274-282.
- 31. Zakharchenko M, Leden P, Rulíšek J, et al. Ionized magnesium and regional citrate anticoagulation for continuous renal replacement therapy. Blood Purif, 2016, 41(1/2/3): 41-47.
- 32. Zakharchenko M, Los F, Brodska H, et al. The effects of high level magnesium dialysis/substitution fluid on magnesium homeostasis under regional citrate anticoagulation in critically ill. PLoS One, 2016, 11(7): e0158179.
- 33. Jeffrey YH, Hoi-Ping S, Kit Hung AL, et al. Experiences with continuous venovenous hemofiltration using 18 mmol/L predilution citrate anticoagulation and a phosphate containing replacement solution. Indian J Crit Care Med, 2017, 21(1): 11-16.
- 34. Adrogué HJ, Madias NE. Assessing acid-base status: physiologic versus physicochemical approach. Am J Kidney Dis, 2016, 68(5): 793-802.
- 35. Nagaoka D, Nassar Junior AP, Maciel AT, et al. The use of sodium-chloride difference and chloride-sodium ratio as strong ion difference surrogates in the evaluation of metabolic acidosis in critically ill patients. J Crit Care, 2010, 25(3): 525-531.
- 36. Mehta RL, McDonald BR, Aguilar MM, et al. Regional citrate anticoagulation for continuous arteriovenous hemodialysis in critically ill patients. Kidney Int, 1990, 38(5): 976-981.
- 37. Hetzel GR, Taskaya G, Sucker C, et al. Citrate plasma levels in patients under regional anticoagulation in continuous venovenous hemofiltration. Am J Kidney Dis, 2006, 48(5): 806-811.
- 38. Schultheiβ C, Saugel B, Phillip V, et al. Continuous venovenous hemodialysis with regional citrate anticoagulation in patients with liver failure: a prospective observational study. Crit Care, 2012, 16(4): R162.
- 39. Tan JN, Haroon SWP, Mukhopadhyay A, et al. Hyperlactatemia predicts citrate intolerance with regional citrate anticoagulation during continuous renal replacement therapy. J Intensive Care Med, 2019, 34(5): 418-425.
- 40. Zhang W, Bai M, Yu Y, et al. Safety and efficacy of regional citrate anticoagulation for continuous renal replacement therapy in liver failure patients: a systematic review and meta-analysis. Crit Care, 2019, 23(1): 22.
- 41. Lahmer T, Messer M, Rasch S, et al. Sustained low-efficiency dialysis with regional citrate anticoagulation in medical intensive care unit patients with liver failure: a prospective study. J Crit Care, 2015, 30(5): 1096-1100.
- 42. Slowinski T, Morgera S, Joannidis M, et al. Safety and efficacy of regional citrate anticoagulation in continuous venovenous hemodialysis in the presence of liver failure: the liver citrate anticoagulation threshold (L-CAT) observational study. Crit Care, 2015, 19: 349.
- 43. Klingele M, Stadler T, Fliser D, et al. Long-term continuous renal replacement therapy and anticoagulation with citrate in critically ill patients with severe liver dysfunction. Crit Care, 2017, 21(1): 294.
- 44. Faybik P, Hetz H, Mitterer G, et al. Regional citrate anticoagulation in patients with liver failure supported by a molecular adsorbent recirculating system. Crit Care Med, 2011, 39(2): 273-279.
- 45. Meijers B, Laleman W, Vermeersch P, et al. A prospective randomized open-label crossover trial of regional citrate anticoagulation vs. anticoagulation free liver dialysis by the molecular adsorbents recirculating system. Crit Care, 2012, 16(1): R20.
- 46. Saner FH, Treckmann JW, Geis A, et al. Efficacy and safety of regional citrate anticoagulation in liver transplant patients requiring post-operative renal replacement therapy. Nephrol Dial Transplant, 2012, 27(4): 1651-1657.
- 47. Khadzhynov D, Schelter C, Lieker I, et al. Incidence and outcome of metabolic disarrangements consistent with citrate accumulation in critically ill patients undergoing continuous venovenous hemodialysis with regional citrate anticoagulation. J Crit Care, 2014, 29(2): 265-271.
- 48. Li L, Bai M, Yu Y, et al. Regional citrate anticoagulation vs no-anticoagulation for CRRT in hyperlactatemia patients with increased bleeding risk: a retrospective cohort study. Semin Dial, 2021, 34(3): 209-217.
- 49. Li L, Bai M, Zhang W, et al. Regional citrate anticoagulation versus low molecular weight heparin for CRRT in hyperlactatemia patients: a retrospective case-control study. Int J Artif Organs, 2022, 45(4): 343-350.
- 50. Khadzhynov D, Dahlinger A, Schelter C, et al. Hyperlactatemia, lactate kinetics and prediction of citrate accumulation in critically ill patients undergoing continuous renal replacement therapy with regional citrate anticoagulation. Crit Care Med, 2017, 45(9): e941-e946.
- 51. Boer W, Van Tornout M, Vander Laenen M, et al. Catheter port reversal in citrate continuous veno-venous hemofiltration. Kidney Int Rep, 2021, 6(11): 2775-2781.