Pediatric large volume peripheral blood progenitor cell collections from patients under 25 kg: a primer

Area of Science:

• Pediatric Hematology
• Cellular Therapy
• Medical Device Technology

Background:

• Collecting peripheral blood progenitor cells (PBPCs) from pediatric patients poses distinct technical and social challenges compared to adults.
• Small patients (<25 kg) require specialized approaches for venous access, anticoagulation, and managing extracorporeal volume ratios.

Purpose of the Study:

• To report on the experience of a single institution performing large-volume PBPC collections in pediatric patients weighing less than 25 kg.
• To analyze the specific challenges and outcomes associated with PBPC collection in this vulnerable population.

Main Methods:

• Retrospective analysis of 85 PBPC collections from 14 pediatric patients (<25 kg) over two years.
• Utilized central venous catheters (CVCs) for access, systemic heparinization with activated clotting time (ACT) monitoring, and citrate anticoagulation.
• Employed a COBE Spectra apheresis system with modified priming and processing protocols to optimize for small patients.

Main Results:

• Achieved a median yield of 4.5 x 10^6/kg CD34+ cells per collection.
• Central venous catheters (7-10 Fr) were uniformly required for venous access.
• Identified and enumerated complications, primarily related to catheter access.

Conclusions:

• Large-volume PBPC collection is feasible and effective in small pediatric patients.
• Careful management of anticoagulation, extracorporeal volume, and venous access is crucial for successful collections.
• The study highlights the importance of addressing both technical and social aspects for optimal pediatric apheresis outcomes.