Manual Single-Lumen Alternating Micro-Batch Device as Renal Replacement Therapy in Austere Environments

Area of Science:

• Nephrology
• Biomedical Engineering
• Emergency Medicine

Background:

• Acute kidney injury (AKI) presents life-threatening emergencies like electrolyte derangements and volume overload, particularly in austere environments.
• Existing renal replacement therapies are often inaccessible in low-resource or remote settings due to equipment and power requirements.

Purpose of the Study:

• To evaluate the feasibility and effectiveness of a novel manual single-lumen alternating micro-batch (mSLAMB) dialysis technique for renal replacement therapy.
• To model and predict the performance of mSLAMB dialysis in terms of solute clearance, blood flow, and ultrafiltration accuracy.

Main Methods:

• A simulated pediatric patient blood volume (2-L expired blood) was used, spiked with urea and potassium.
• Experiments involved 8 cycles with varying hemofiltration fluid to blood volume ratios, measuring urea and potassium concentrations, effluent volumes, and cycle duration.

Main Results:

• The mSLAMB technique achieved a mean urea reduction ratio of 27.4% and potassium reduction of 23.4%.
• Mean blood flow rates ranged from 79.7 to 90.8 mL/min, increasing with larger batch volumes and height differences.
• Ultrafiltration accuracy was high, ranging from 0 to 2.4% per cycle, with peak solute reduction in the first cycle.

Conclusions:

• The manual mSLAMB dialysis technique is a simple, cost-effective method for renal replacement therapy.
• It demonstrates capability for adequate solute clearance and accurate ultrafiltration, offering a potentially life-saving solution for AKI in austere and low-resource settings.