Negative calcium balance despite normal plasma ionized calcium concentrations during citrate anticoagulated continuous venovenous hemofiltration (CVVH) in ICU patients.
Study Goal
The researchers aimed to develop an equation to calculate calcium balance during citrate CVVH and assess calcium supplementation efficacy in ICU patients.
Results Summary
The study found that calcium balance was negative in most patients despite supplementation, potentially contributing to skeletal demineralization. The proposed solution was to base supplementation on both plasma ionized calcium levels and calculated calcium excretion.
Population
ICU patients undergoing continuous venovenous hemofiltration (CVVH) with citrate anticoagulation.
Effective Dosage
Not specified
Duration
Retrospective data from 2014 to 2021
Interactions
None mentioned
| Intervention | Direction | Endpoint | Population | Dosage | Impact | Claim # |
|---|---|---|---|---|---|---|
supplementation of calcium | neutral | target blood ionized calcium concentration | patients during continuous venovenous hemofiltration (CVVH) with citrate anticoagulation | - | titrated using | #1 |
calcium supplementation | neutral | plasma ionized calcium levels | patients during citrate CVVH | - | based on | #2 |
calcium supplementation based on plasma ionized calcium levels | decrease | calcium balance | most patients during citrate CVVH | - | was negative | #3 |
negative calcium balance | decrease | demineralization of the skeleton | patients during citrate CVVH | - | may contribute to | #4 |
BACKGROUND: Supplementation of calcium during continuous venovenous hemofiltration (CVVH) with citrate anticoagulation is usually titrated using a target blood ionized calcium concentration. Plasma calcium concentrations may be normal despite substantial calcium loss, by mobilization of calcium from the skeleton. Aim of our study is to develop an equation to calculate CVVH calcium and to retrospectively calculate CVVH calcium balance in a cohort of ICU-patients. METHODS: This is a single-center retrospective observational cohort study. In a subcohort of patients, all calcium excretion measurements in patients treated with citrate CVVH were randomly divided into a development set (n = 324 in 42 patients) and a validation set (n = 441 in 42 different patients). Using mixed linear models, we developed an equation to calculate calcium excretion from routinely available parameters. We retrospectively calculated calcium balance in 788 patients treated with citrate CVVH between 2014 and 2021. RESULTS: Calcium excretion (mmol/24 h) was - 1.2877 + 0.646*[Ca] CONCLUSION: During citrate CVVH, calcium balance was negative in most patients, despite supplementation of calcium based on plasma ionized calcium levels. This may contribute to demineralization of the skeleton. We propose that calcium supplementation should be based on both plasma ionized calcium and a simple calculation of calcium excretion by CVVH.