Mathematics of apheresis.

Mathematics is related to apheresis medicine. The safety of donor and patient in taking blood components is utterly important. Knowledge of total blood and plasma volume is needed and have to be calculated. By increasing quality, the safety of not only the donor and patient, but also the operator will increase, as well as the efficiency of operating an apheresis collection facility. Various concepts, formulas and calculations methods and their significance in apheresis are given in this paper.

Basics of apheresis and equipment.

Apheresis is a method of obtaining one or more blood components by machine processing of whole blood in which the residual components are returned to the donor or patient during or at the end of the process. To achieve this, the desired blood component is separated from the whole blood using centrifugal, filtration and or adsorption techniques. Although the apheresis equipment from various manufacturers look from the outside very different, the working is rather similar with separation in a one-use disposable, connected with bacterial filters to the machine, and various safety features to achieve optimal safety for donor / patient, operator and product.

Apheresis machines variably overestimate mononuclear cell collection volume.

INTRODUCTION: Calculation of the actual number of CD34+ cells in the collection product is based on the volume of the collected product and its concentration of CD34+ cells measured in the lab. The number of CD34+ cells infused correlates closely with the pace of hematopoietic reconstitution following autologous or allogeneic stem cell transplantation. METHODS: We studied peripheral blood stem cell collections in a single apheresis center with two Spectra Optia devices, using mononuclear cell collection or continuous mononuclear cell collection procedures. The collection volume displayed by the apheresis device was compared with the volume determined by a weight-based method. RESULTS: Fifty-two consecutive CD34 collections in 35 different donors (range 1-4 daily procedures per donor) were analyzed. The machines reported larger collection volumes (P < .001). The mean collection volume reported by the machine was 274.37 mL (range 162-396). The mean manually measured collection volume was 261.82 mL (range 155-371.40). Mean overestimation by machine was 12.53 mL (range -0.95 to 31.24; 95% confidence interval 10.94-14.11) or 4.88% (range -0.26 to 10.28). Median overestimation of the absolute number of CD34 was 10.29 × 106 (range -2.83 to 141.84 × 106 ). CONCLUSION: Both Spectra Optia machines overestimated the collection volume after peripheral blood stem cell collection. Although the mean variation falls within the expected range, in some cases, this overestimation may be clinically relevant if no other method of measurement is used.

Therapeutic plasma apheresis: Expertise and indications.

Therapeutic apheresis is an extracorporeal treatment that is capable of removing pathogenic blood components from patients that causes morbidity. In this review an overview is given of the types of indications for which therapeutic plasma exchange is effective. Furthermore, practical and effective topics, as well as complications will be discussed.

Performance of an apheresis procedure: The apheresis nurse-operator and nursing aspects.

Thousands of apheresis procedures are performed on a daily basis. Procedures such as plasmapheresis in donors are of shorter procedure time, but others will take many hours. Operators usually learn to operate the apheresis machine, but more and more attention needs to be paid to the non-technical aspects of an apheresis procedure. For handling all social, emotional and ethical aspects during the complete procedure, the apheresis nurse/operator needs to have numerous skills besides the specific basic knowledge regarding nursing and how to handle the machine. The knowledge of an apheresis nurse should cover various areas with general, administrative and, technical skills regarding the equipment you're working with, besides social and communicative skills.

Calculations in apheresis.

It's important to work smoothly with your apheresis equipment when you are an apheresis nurse. Attention should be paid to your donor/patient and the product you're collecting. It gives additional value to your work when you are able to calculate the efficiency of your procedures. You must be capable to obtain an optimal product without putting your donor/patient at risk. Not only the total blood volume (TBV) of the donor/patient plays an important role, but also specific blood values influence the apheresis procedure. Therefore, not all donors/patients should be addressed in the same way. Calculation of TBV, extracorporeal volume, and total plasma volume is needed. Many issues determine your procedure time. By knowing the collection efficiency (CE) of your apheresis machine, you can calculate the number of blood volumes to be processed to obtain specific results. You can calculate whether you need one procedure to obtain specific results or more. It's not always needed to process 3× the TBV. In this way, it can be avoided that the donor/patient is needless long connected to the apheresis device. By calculating the CE of each device, you can also compare the various devices for quality control reasons, but also nurses/operators.

Apheresis training for nurses and physicians around the World.

A training program for apheresis nurses in leukocyte collection and therapeutic apheresis was developed by the Joint Task Force for Apheresis Education and Certification. This is a modular program with theoretical and practical information and knowledge. On request of the Indonesian authorities, in the capital of Indonesia Jakarta, a certification course for apheresis nurses/operators based on the training program described above was organized in December 2013. The course existed of themes related to apheresis, such as hematology, anatomy, physiology, calculations, adverse events, basics of apheresis, nursing aspects, quality, collection of cells for cellular therapies, pediatrics, and therapeutic collections (cell reductions and exchange procedures). A pretest and post-test regarding the knowledge and judgment in the themes described was taken in Bahasa Indonesia or in English. In total, 38 apheresis nurses and 32 physicians participated in the course. In the post-test, the nurses scored in a mean 72/100 and the physicians 77/100 (nurses vs. physicians: P = 0.005), which was significantly better than the results of the pretest (54/100 and 53/100, respectively (P < 0.0001 for both). In conclusion, with this course, 38 apheresis nurses/operators proved a significant increase of knowledge in the theory behind apheresis. This educational program provides an approach to educate and certificate apheresis nurses. It is also shown that also for physicians working in the field of apheresis, this course is of use increasing their knowledge regarding apheresis.