title: Incidence and outcome of metabolic disarrangements consistent with citrate accumulation in critically ill patients undergoing continuous venovenous hemodialysis with regional citrate anticoagulation.
abstract: BACKGROUND
  Systemic citrate accumulation is a complication of regional citrate anticoagulation (RCA) during continuous renal replacement therapy (CRRT). Our objective was to determine the incidence of clinical signs consistent with citrate accumulation in a large and representative cohort of intensive care unit patients undergoing RCA-CRRT.
  
  
  METHODS
  Patients treated with RCA-CRRT during 2008-2010 were retrospectively analyzed. Decreased systemic ionized calcium (iCa), increased demand for calcium substitution, elevated total calcium to iCa ratio, and metabolic acidosis were evaluated as indicators for citrate accumulation.
  
  
  RESULTS
  In the 3-year period, 1070 patients were treated with RCA-continuous venovenous hemodialysis. Metabolic signs of citrate accumulation occurred in 32 patients (2.99%, 64.5 ± 14.0 years, 65.6% male, Acute Physiology and Chronic Health Evaluation score 34.2 ± 9.7): systemic iCa decreased to 1.01 ± 0.10 mmol/L with a simultaneous increase of the calcium substitution rate to 129% ± 26%, and the mean total calcium to iCa ratio increased to 2.51 ± 0.54. All 32 patients had therapy-resistant shock with severe lactic acidosis (pH 7.20 ± 0.11, lactate 136 ± 61 mg/dL), indicating severe intracellular hypoxia. None of the patients survived.
  
  
  CONCLUSIONS
  The incidence of disarrangements consistent with citrate accumulation in patients undergoing RCA-continuous venovenous hemodialysis was low, taking place exclusively in patients with severe lactic acidosis due to multiorgan failure. This suggests that the appearance of citrate accumulation is secondary to a severe failure of cellular respiration.
authors.affiliation: Department of Nephrology, Charité Universitätsmedizin Berlin, Charité Campus Mitte, Humboldt University Berlin, D-10117 Berlin, Germany. Electronic address: dmytro.khadzhynov@charite.de.
authors.forename: Dmytro
authors.initials: D
authors.lastname: Khadzhynov
authors.affiliation: Department of Nephrology, Charité Universitätsmedizin Berlin, Charité Campus Mitte, Humboldt University Berlin, D-10117 Berlin, Germany. Electronic address: christin.baumann@charite.de.
authors.forename: Christin
authors.initials: C
authors.lastname: Schelter
authors.affiliation: Department of Nephrology, Charité Universitätsmedizin Berlin, Charité Campus Mitte, Humboldt University Berlin, D-10117 Berlin, Germany. Electronic address: ina.lieker@charite.de.
authors.forename: Ina
authors.initials: I
authors.lastname: Lieker
authors.affiliation: Department of Nephrology, Charité Universitätsmedizin Berlin, Charité Campus Mitte, Humboldt University Berlin, D-10117 Berlin, Germany. Electronic address: alice.mika@charite.de.
authors.forename: Alice
authors.initials: A
authors.lastname: Mika
authors.affiliation: Department of Nephrology, Charité Universitätsmedizin Berlin, Charité Campus Mitte, Humboldt University Berlin, D-10117 Berlin, Germany. Electronic address: oliver.staeck@charite.de.
authors.forename: Oliver
authors.initials: O
authors.lastname: Staeck
authors.affiliation: Department of Nephrology, Charité Universitätsmedizin Berlin, Charité Campus Mitte, Humboldt University Berlin, D-10117 Berlin, Germany. Electronic address: hans-h.neumayer@charite.de.
authors.forename: Hans-H
authors.initials: HH
authors.lastname: Neumayer
authors.affiliation: Department of Nephrology, Charité Universitätsmedizin Berlin, Charité Campus Mitte, Humboldt University Berlin, D-10117 Berlin, Germany. Electronic address: Harm.Peters@charite.de.
authors.forename: Harm
authors.initials: H
authors.lastname: Peters
authors.affiliation: Department of Nephrology, Charité Universitätsmedizin Berlin, Charité Campus Mitte, Humboldt University Berlin, D-10117 Berlin, Germany. Electronic address: torsten.slowinski@charite.de.
authors.forename: Torsten
authors.initials: T
authors.lastname: Slowinski
mesh_terms: D058186:Acute Kidney Injury / Q000097:blood* / Q000628:therapy; D000368:Aged; D000925:Anticoagulants / Q000009:adverse effects; D002118:Calcium / Q000097:blood*; D002951:Citrates / Q000009:adverse effects / Q000097:blood*; D019343:Citric Acid; D016638:Critical Illness; D005260:Female; D006801:Humans; D015994:Incidence; D008297:Male; D008659:Metabolic Diseases / Q000097:blood; D008875:Middle Aged; D017582:Renal Replacement Therapy / Q000009:adverse effects* / Q000379:methods; D012189:Retrospective Studies
chemical_list: D000925:Anticoagulants; D002951:Citrates; D019343:Citric Acid; D002118:Calcium
keywords: Acute renal injury; Citrate accumulation; Citrate anticoagulation; Continuous renal replacement therapy; Continuous venovenous hemodialysis; Lactate acidosis