Magnesium Balance of Citrate-based Continuous Venovenous Hemofiltration, Effect of Citrate Dose.
Status:
Completed
Trial end date:
2017-06-01
Target enrollment:
Participant gender:
Summary
Rationale:
A higher citrate dose during continuous venovenous hemofiltration provides better
anticoagulation but possibly a higher risk of citrate accumulation in case of metabolic
limitations. A higher citrate dose also increases magnesium loss in ultrafiltrate, while a
negative magnesium balance is unwanted.
Objective:
Aim of this study is to determine the magnesium balance of citrate-based continuous
veno-venous hemofiltration (CVVH) and to determine whether and to which extent the magnesium
balance depends on citrate dose.
Study design and methods:
A prospective randomized study conducted in critically ill patients with acute kidney injury
(AKI), treated with CVVH, with either low dose citrate (2.5 mmol/L blood flow in the filter)
or high dose citrate (4.5 mmol/L blood flow in the filter) as anti-coagulant, targeting a
postfilter ionized Calcium (iCa) of resp. 1.3-1.6 mg/dL (0.325-0.4 mmol/L) and 0.8-1.1 mg/dL
(0.2-0.275 mmol/L). Post-filter blood as well as effluent aliquots and bloodconcentrations in
the patient are tested for the following variables:
(0 , 2 , 4, 6, 12 and 24 hrs): Total Magnesium (tMg) and total Calcium (tCa), ionized Ca
(iCa)(bloodgas analyzer). In addition, hematocrit, albumin, total protein, ureum and
creatinine and parathormone (PTH) are determined in arterial blood at 0 and 24 hrs or at the
time of protocol exit and citrate concentrations in postfilter and arterial blood at 1 and 24
hrs or at protocol exit.
Sample sites: arterial line, postfilter port (after postdilution and calcium compensation),
effluent sample. All flow rates to be noted.
Study population:
Twenty patients admitted to intensive care, requiring continuous renal replacement therapy
(CRRT) for AKI.
Intervention:
Anti-coagulation with either low dose citraat (2.5 mmol/L blood flow) or high dose citraat
(4.5 mmol/L blood flow) targeting postfilter iCa of resp. 1.3-1.6 and 0.8-1.1 mg/dL. Both
regimens are within standard protocolled CVVH treatment in the intensive care department.