Use of percutaneous radial artery catheter for peripheral blood progenitor cell collection in pediatric patients

Efficacy of peripheral arterial access for peripheral blood stem cells collection

BACKGROUND

Transplantation of peripheral blood stem cells (PBSCs) mobilized by cytokines is increasingly applied to treat patients with hematologic diseases, such as lymphoma, multiple myeloma, leukemia, etc. Successful hematopoietic stem cell transplantation (HSCT) increasingly depends on the collection of hematopoietic stem cells (HSCs) from peripheral blood. Peripheral vein (PV) is the most common type of blood access. When the blood vessels are not well filled and the blood flow is insufficient, the machine will appear repeated low pressure alarm or pipeline coagulation, which seriously affects the collection efficiency. A peripheral artery (PA) is utilized for drawing blood, while a peripheral vein is used for blood return, that is a way to perform apheresis. The advantages of PA are that it ensures adequate extracorporeal circulation blood flow, stable blood flow rate, simple operation, and relatively low price. However, there are very few studies on the efficacy of peripheral arterial access for HSCs collection. Therefore, this retrospective study was conducted to assess the effectiveness of PA and PV access for PBSCs collection.

METHODS

We performed a retrospective analysis of 150 apheresis procedures on 26 patients and 95 healthy donors collected by PV or PA access from March 1, 2020 to March 1, 2021. We compared the CD34+ cell count, collection efficiency (CE), duration of processing a single blood volume, number of low-pressure alarms, average blood flow rate and number of punctures between the two groups. Also, we analyzed adverse events.

RESULTS

There was no significant difference in the quality of apheresis blood components between the PA group and the PV group. The CD34+ cells collected was 274.16 ± 216.31 × 10⁶ in the PV group and 246.63 ± 127.94 × 10⁶ in the PA group. The CE in the PA group was 49.50 ± 9.88%, higher than 42.39 ± 14.62% in the PV group. The duration of processing a single blood volume was 90.67 ± 15.35 min in the PV group and 79.68 ± 10.28 min in the PA group. The number of low-pressure alarms in the PA group was 0.38 ± 0.98, <2.42 ± 1.76 in the PV group, and the average blood flow rate in the PA group was 59.27 ± 2.18, higher than 54.21 ± 3.41 in the PV group. The difference was statistically significant (P < .05). The Number of punctures was 1.35 ± 0.75 in the PA group and 1.41 ± 1.01 in the PV group. There was no statistically significant difference.

CONCLUSION

Peripheral artery is a safe, reliable, economical, convenient, and fast vascular access, which opens a new way to the establishment of vascular access for PBSCs collection.

Optimized peripheral blood progenitor cell mobilization for autologous hematopoietic cell transplantation in children with high-risk and refractory malignancies

BACKGROUND

Autologous hematopoietic stem cell transplantation (aHSCT) using hematopoietic progenitor cells (HPCs) has become an important therapeutic modality for patients with high-risk malignancies. Current literature on standardized method for HPC apheresis in children is sparse and failure rate reported as high as 30%.

PATIENTS/METHODS

A retrospective study of 125 pediatric patients with high-risk malignancies undergoing aHSCT in Western Australia between 1997 and 2016 was conducted.

RESULTS

Mobilization was achieved by means of chemotherapy and granulocyte colony-stimulating factor (G-CSF). Patients underwent apheresis the day after CD34⁺ counts reached ≥20/µL and an additional dose of G-CSF. Peripheral arterial and intravenous lines were inserted in pediatric intensive care unit under local anesthetic and/or sedation, omitting the need for general anesthesia as well as facilitating an uninterrupted apheresis flow. Larger apheresis total blood volumes were processed in patients weighing ≤20 kg. The minimal dose of ≥2 × 10⁶ CD34⁺ cells/kg was successfully collected in 98.4% of all patients. The optimal dose of 3-5 × 10⁶ CD34⁺ cells/kg was collected in 96% of patients scheduled for a single aHSCT, 87.5% for tandem, and 100% for triple aHSCT. All HPC collections were completed in one apheresis session. Mobilization after ≤3 chemotherapy cycles and cycles including cyclophosphamide resulted in a significantly higher yield of CD34⁺ cells.

CONCLUSION

Our approach to HPC mobilization by means of chemotherapy and single myeloid growth factor combined with optimal collection timing facilitated by continuous apheresis flow resulted in highly effective HPC harvest in children and adolescents with high-risk cancers.

Mobilized peripheral blood stem cell apheresis via Hickman catheter in pediatric patients

BACKGROUND

Autologous stem cell transplantation remains an integral treatment tool for certain childhood malignancies. In children, a central venous catheter is typically necessary to provide adequate flow rates for preparative apheresis. In this study, the feasibility and efficiency of collecting CD34+ cells via an indwelling Hickman catheter, preimplanted for chemotherapy, instead of placing an additional temporary central venous catheter was evaluated.

STUDY DESIGN AND METHODS

Forty-eight pediatric leukaphereses for autologous hematopoietic stem cell transplantation using Spectra Optia MNC, Version 3.0 were reviewed. We compared preimplanted Hickman catheters with a temporary Shaldon catheter, inserted for apheresis. Apheresis was considered successful if a dose of 2 × 10⁶ CD34+ peripheral blood stem cells/kg BW was achieved.

RESULTS

In 43 (89.6%) of the 48 patients, a Hickman catheter was used for leukapheresis. Only 5 patients (10.4%) received a temporary Shaldon catheter. In both groups, apheresis was performed without apparent adverse reactions. The dose of collected CD34+ peripheral blood stem cells was 12.7 × 10⁶ (range, 2.3-70.7 × 10⁶ ) cells/kg BW in the Hickman group and 16.2 × 10⁶ (range, 3.8-48.4 × 10⁶ ) cells/kg BW in the Shaldon group, showing no statistically significant difference (p = 0.58). In both groups, the primary endpoint of a minimal CD34+ cell concentration of 2 × 10⁶ cells/kg BW was achieved at a maximum of two leukapheresis sessions. Apheresis efficacy was further confirmed by the collection efficiency of 40.2% in the Hickman group and 27.8% in the Shaldon group (p = 0.32).

CONCLUSION

These data indicate the reliable feasibility and efficacy of mobilized apheresis via an indwelling Hickman catheter. In light of this, the routine insertion of a dialysis catheter for the purpose of leukapheresis should be critically reconsidered.

Collection of hematopoietic stem cells and immune effector cells in small children

Apheresis procedures are standard of care for a wide range of indications in children, collection of hematopoietic stem cells being the most frequent one. With increasing numbers of hematopoietic stem cell transplants, advances in graft manipulation techniques and the development of innovative therapies using immune effector cells and gene therapy, apheresis within the pediatric population is growing in demand. While young children have higher circulating white blood cell counts and robustly mobilize hematopoietic stem cells, apheresis machines were designed for use within the adult population and apheresis procedures in children, particularly small children, can be more challenging as vascular access, collection techniques and impact of extracorporeal volumes increase the rate of adverse events. In this article we review topics of particular relevance to hematopoietic stem cell and immune effector cell collections in small children.

Vascular access for therapeutic plasma exchange

Therapeutic plasma exchange is an apheresis modality in which plasma is separated from the blood cellular components ex vivo, discarded, and replaced with an isosmotic fluid (most commonly 5% albumin) to maintain appropriate oncotic pressure in the patient. Therapeutic plasma exchange is used in the treatment of many diseases and indications. The recent seventh edition of the American Society for Apheresis guidelines indicates approximately 72 diseases and 116 indications for which therapeutic plasma exchange may be effective. One of the critical aspects for the successful performance of therapeutic plasma exchange is appropriate vascular access to provide high blood flow for the collection and return phases of the procedure, especially because most patients who need therapeutic plasma exchange will require more than one treatment over days to weeks. This article provides an overview of the characteristics of therapeutic plasma exchange, the clinical diseases and indications that may be treated with therapeutic plasma exchange, and the different types of vascular access employed, with their advantages and disadvantages. The latter may include peripheral venous access and intravascular or implantable access devices, such as arteriovenous grafts and fistulas, central venous catheters, and central venous catheters tunneled with ports.

Solutions to technical challenges during therapeutic plasma exchange using the Spectra Optia on a 4 kilogram neonate

Therapeutic plasma exchange (TPE) on severely ill neonates poses many technical challenges, including obtaining adequate vascular access. In addition, clinical challenges such as risk of hypotension and cardiovascular instability are more pronounced in these patients. We report an approach to successfully managing these challenges while performing TPE on a 4 kilogram neonate using the Spectra Optia and 22 G venous access.

Performance and safety of femoral central venous catheters in pediatric autologous peripheral blood stem cell collection

INTRODUCTION

Autologous peripheral blood hematopoietic progenitor cell collection (A-HPCC) in children typically requires placement of a central venous catheter (CVC) for venous access. There is scant published data regarding the performance and safety of femoral CVCs in pediatric A-HPCC.

METHODS

Seven-year, retrospective study of A-HPCC in pediatric patients collected between 2009 and January 2017. Inclusion criteria were an age ≤ 21 years and A-HPCC using a femoral CVC for venous access. Femoral CVC performance was examined by CD34 collection rate, inlet rate, collection efficiency (MNC-FE, CD34-FE), bleeding, flow-related adverse events (AE), CVC removal, and product sterility testing. Statistical analysis and graphing were performed with commercial software.

RESULTS

A total of 75/119 (63%) pediatric patients (median age 3 years) met study criteria. Only 16% of children required a CVC for ≥ 3 days. The CD34 collect rate and CD34-FE was stable over time whereas MNC-FE decreased after day 4 in 80% of patients. CD34-FE and MNC-FE showed inter- and intra-patient variability over time and appeared sensitive to plerixafor administration. Femoral CVC showed fewer flow-related AE compared to thoracic CVC, especially in pediatric patients (6.7% vs. 37%, P = 0.0005; OR = 0.12 (95%CI: 0.03-0.45). CVC removal was uneventful in 73/75 (97%) patients with hemostasis achieved after 20-30 min of pressure. In a 10-year period, there were no instances of product contamination associated with femoral CVC colonization.

CONCLUSION

Femoral CVC are safe and effective for A-HPCC in young pediatric patients. Femoral CVC performance was maintained over several days with few flow-related alarms when compared to thoracic CVCs.

Peripheral blood stem-cell harvest using percutaneous arterial lines in children

BACKGROUND

Autologous peripheral blood stem-cell collection (PBSCC) in children has become an integral part of contemporary treatment protocols, but the procedure is often complicated due to technical issues related to vascular access. Central line placement is often implemented to surmount this problem, but is associated with complications such as bleeding, thrombosis and pneumothorax. As an alternative we have introduced the use of radial arterial lines for PBSCC in children.

PROCEDURE

Data from autologous stem cell collections performed from October 2002 to December 2011 using a radial arterial line were collected.

RESULTS

A total of 372 PBSCC procedures were performed during the study period; an arterial line was used in 311 PBSCC's in 208 children. The average patient age and weight were 7.9 years (SD 5.4) and 28.3 kg (SD 20.4), respectively. The smallest patient was 9 months old and weighed 7 kg. The mean total volume processed was 8,593 cm(3) (SD 4,854), and the mean number of blood volumes processed was 4.3. Mean collection time for a single blood volume was 55 minutes (SD 15.5). The mean number of CD34+ cells collected per donation was 5.8 × 10(6) /kg. Ninety-seven patients (46%) required more than one collection to meet the requested CD34+ cell target. No serious adverse effects associated with vascular access occurred in this cohort.

CONCLUSION

Percutaneous placement of radial artery catheters can be rapidly and safely performed in very small infants and in children with difficult venous access. This technique provides a reliable platform for efficient PBSCC.

Leukapheresis in children weighing less than 20 kg

Augmentation of standard chemotherapy with peripheral blood stem cells (PBSC) rescue is a standard treatment strategy. However, in pediatric patients weighing less than 20 kg, the collection of PBSC presents a challenge. We report our experience with nine pediatric patients weighing between 4.33 and 19.9 kg and a total of 23 PBSC collection aphereses. None of our patients experienced any major complications. We conclude that PBSC apheresis in children is a safe method. It should be based on a standardized procedure that includes the determination of clinical and laboratory parameters and appropriate monitoring.

Peripheral blood stem cell collection in children: Management, techniques and safety

Peripheral blood stem cell (PBSC) collection as a source of haematopoietic stem cells is steadily increasing. The collection procedure in children is more difficult than in adults because of the low blood volume and the poor venous access. Special apheresis equipment has been developed for paediatric PBSC collections to reduce the extracorporeal volume thereby avoiding circulatory side effects. Priming of the disposable with red blood cells and/or human albumin is recommended for children weighing less than 30kg. Poor venous access usually requires a special paediatric catheter to allow for a blood flow that results in the formation of a cell layer for the collection of PBSC. An optimal time point with a maximum peak of CD34+ cells should be chosen for the harvesting of PBSC to reduce the duration of the apheresis and possible side effects.

Peripheral blood progenitor uncontrolled-rate freezing: a single pediatric center experience

BACKGROUND

Controlled-rate freezing (CRF) followed by storage in liquid nitrogen is employed by most centers as the standard procedure for peripheral blood progenitor cell (PBPC) cryopreservation. Uncontrolled-rate freezing (URF) at -80 degrees C is more simple, time-saving, less expensive, and, possibly, as effective as CRF. The aim of this retrospective analysis was to compare CRF and URF in childhood transplantation.

STUDY DESIGN AND METHODS

A total of 54 PBPC transplants performed in 39 children aged 3 to 16 years (median, 9.5 years) were analyzed: 23 transplants in 16 children with CRF versus 31 transplants performed in 23 children with -80 degrees C URF. All grafts contained at least 2 x 10(6) per kg unselected CD34+ cells, enumerated before freezing. Nucleated cells infused ranged from 1.32 x 10(8) to 4.3 x 10(8) per mL with a median of 3.1 x 10(8) per mL. Cryoprotectant solution consisted of a final dimethyl sulfoxide (DMSO) concentration of 10 percent DMSO with autologous plasma.

RESULTS

The two study groups did not differ in terms of timing of neutrophil and platelet recovery or transfusion requirements. Adverse events related to graft infusion, severe complications, and transplant-related mortality were not significantly different between CRF and URF groups. In both groups only mild adverse events were observed during graft administration. URF procedures, however, were simpler and less expensive. At a median follow-up of 72 months, no secondary myelodysplasia was observed in either group.

CONCLUSION

Our analysis suggests that URF is safe and effective in the pediatric population.

Peripheral blood stem cell collection in pediatric patients: feasibility of leukapheresis under anesthesia in uncompliant small children with solid tumors

Leukapheresis demands patient's compliance and adequate vascular accesses, which can require invasive methods in very small children whose treatment protocol includes hemopoietic stem cell collection for myeloablative chemotherapy and stem cell rescue. Since 1998, at the Istituto Nazionale Tumori of Milan, in selected uncompliant small children, the placement of peripheral vascular accesses and leukapheresis have been performed at the same time under general anesthesia. Peripheral venous cannulas were positioned for blood collection, while blood was returned through either peripheral cannulas or mono-lumen central catheters previously installed for chemotherapy. A continuous-flow cell separator was used for leukapheresis. Between 1998 and 2003, 47 children with solid tumors underwent anesthesia for a total of 54 leukaphereses. The patients' age ranged from 12.7 to 93 months (median 30.3) and their weight ranged from 7 to 20 kg (median 14.1). Neither metabolic nor anesthesiological complications were recorded. In 89% of cases, the CD 34(+) cell target was achieved at a single harvest; the median number of CD 34(+) cells was 10.8 x 10(6)/kg/leukapheresis (range 1-117) and the median collection efficiency was 63.4% (range 25-100.6). Leukapheresis under anesthesia is feasible and safe in very low-weight children whose compliance is lacking due to age and disease.

Risks and methods for peripheral blood progenitor cell collection in small children

Peripheral blood progenitor cells (PBPC) are increasingly used as a source of stem cells for either autologous or allogeneic hematopoietic transplantation in children. Although technically similar to adult procedures, apheresis in small children worries some operators and physicians that have little experience in managing pediatric patients or donors. However several published series have showed that these procedures, when performed by experienced teams are safe and can obtain enough amount of PBPC for either autologous or allogeneic hematopoietic transplantation. Some technical aspects must be considered in pediatric apheresis due to the size of the patient/donor. Factors that must be evaluated are extracorporeal circuit volume, blood flow rates, type of anticoagulant and vascular access. Other important issue to be considered is the emotional stress for them and their relatives. Leukaphereses in children may be performed with any of the reported continuous blood cell separator without sedation. Adverse events are mainly related either to vascular access or to metabolic or hemodynamic changes. Anyway, taking all these complications together, they are not higher than those adverse events or toxicities reported after general anesthesia and bone marrow harvesting.

Cellular transplantation

This article reviews the scant literature that exists describing the interface between anesthesiologists and marrow donors and islet recipients, introduces the issues surrounding future stem cell transplantation technologies, and describes pretranslational cell transplant applications that are closest to clinical trials.