Continuous Renal Replacement Therapy for Acute Kidney Injury Using Phosphate
Containing Fluid is Associated With Greater Biochemical Derangement than Conventional Fluid
Acute kidney injury is increasingly common in critically ill patients and associated
with significant morbidity and mortality.
One large multicenter study showed that over 16% of critically ill patients are diagnosed
with AKI within forty-eight hours of ICU admission with a 22% overall incidence of AKI
during ICU admission, as defined by the RIFLE classification.
AKI is an independent risk factor for death. In hospital mortality for patients with AKI exceeds 25%4
and mortality amongst ICU patients requiring renal replacement therapy
approaches 70%.
Continuous renal replacement therapy is the favored treatment modality
for AKI in critically ill patients in Australasia. Many units, including ours,
use Hemosol-B0 as their standard CRRT fluid.
Hemosol-B0 does not contain PO4 3- or K+ , leaving patients susceptible
to hypophosphatasemia and hypokalemia unless plasma levels are assiduously
monitored and maintained.
Depending on CRRT intensity and duration the incidence of hypophosphatasemia
with CRRT can exceed 65%.
Phosphate is required to form the high-energy bond that provides
the major energy currency required for metabolism.
Complications of hypophosphatemia include respiratory muscle dysfunction
and prolonged respiratory failure, cardiac dysrhythmia, reduced myocardial
contractility and neuromuscular depression.
The biochemical consequences of replacing Hemosol-B0 with Phoxilium
as the default CRRT fluid to an unselected patient cohort, and the potential
benefit of minimizing handling of concentrated K+ solutions, remain unknown.
Nephrol Open J. 2016; 2(1): 17-22. doi: 10.17140/NPOJ-2-114