Manual Single-Lumen Alternating Microbatch Dialysis to Deplete Stored Blood Potassium: A Potential Use for Children with Severe Malaria-Associated Acute Kidney Injury

Acute kidney injury (AKI) remains a common cause of preventable death in low-resource settings because of cost and lack of dialysis access. AKI occurs in 24-59% of children with severe malaria, and when severe malaria-associated acute kidney injury (SM-AKI) is complicated by hyperkalemia, mortality approaches 40%. Treatment of these children with severe anemia becomes challenging as packed red blood cells (pRBCs) have high potassium (K+) loads. We describe a protocol using the novel manual single-lumen alternating microbatch (mSLAMB) dialysis system to deplete pRBCs of K+, hypothesizing that this system can decrease K+ >80% in 20 minutes. Herein, we ran pRBC aliquots through the mSLAMB system using diffusive clearance. Three cycles were completed in each of four experiments. K+ was measured at baseline and after every cycle to calculate K+ reduction. Active ultrafiltration was performed to control net volumes, assessed as percentage of blood volume reduction and hematocrit rise. We reduced K+ in pRBC aliquots by a median of 93.2% (interquartile range [IQR], 89.9-95.1) in a median of 20.5 minutes (IQR, 17.8-23.1) per experiment. Greatest median K+ reduction occurred in cycle 1 (80.9%; IQR, 80.8-80.9), with minimal additional clearance achieved by cycle 3. Median hematocrit rise at experiment conclusion was 2.5% (IQR, 1.8-3.3). We conclude that mSLAMB dialysis consistently and effectively removed >80% of K+ from pRBCs in just over 20 minutes and facilitated volume control. Further studies are assessing transfusion risks in children with SM-AKI and hyperkalemia as this technique may allow for safer resuscitation.