Temperature course and distribution during plasma heating with a microwave device

Cryopreservation: A Comprehensive Overview, Challenges, and Future Perspectives

Cryopreservation is the most prevalent method of long-term cell preservation. Effective cell cryopreservation depends on freezing, adequate storage, and correct thawing techniques. Recent advances in cryopreservation techniques minimize the cellular damage which occurs while processing samples. This article focuses on the fundamentals of cryopreservation techniques and how they can be implemented in a variety of clinical settings. The article presents a brief description of each of the standard cryopreservation procedures, such as slow freezing and vitrification. Alongside that, the membrane permeating and nonpermeating cryoprotectants are briefly discussed, along with current advancements in the field of cryopreservation and variables influencing the cryopreservation process. The diminution of cryoinjury incurred by the cell via the resuscitation process will also be highlighted. In the end application of cryopreservation techniques in many fields, with a special emphasis on stem cell preservation techniques and current advancements presented. Furthermore, the challenges while implementing cryopreservation and the futuristic scope of the fields are illustrated herein. The content of this review sheds light on various ways to enhance the output of the cell preservation process and minimize cryoinjury while improving cell revival.

New Approaches to Cryopreservation of Cells, Tissues, and Organs

In this concept article, we outline a variety of new approaches that have been conceived to address some of the remaining challenges for developing improved methods of biopreservation. This recognizes a true renaissance and variety of complimentary, high-potential approaches leveraging inspiration by nature, nanotechnology, the thermodynamics of pressure, and several other key fields. Development of an organ and tissue supply chain that can meet the healthcare demands of the 21st century means overcoming twin challenges of (1) having enough of these lifesaving resources and (2) having the means to store and transport them for a variety of applications. Each has distinct but overlapping logistical limitations affecting transplantation, regenerative medicine, and drug discovery, with challenges shared among major areas of biomedicine including tissue engineering, trauma care, transfusion medicine, and biomedical research. There are several approaches to biopreservation, the optimum choice of which is dictated by the nature and complexity of the tissue and the required length of storage. Short-term hypothermic storage at temperatures a few degrees above the freezing point has provided the basis for nearly all methods of preserving tissues and solid organs that, to date, have proved refractory to cryopreservation techniques successfully developed for single-cell systems. In essence, these short-term techniques have been based on designing solutions for cellular protection against the effects of warm and cold ischemia and basically rely upon the protective effects of reduced temperatures brought about by Arrhenius kinetics of chemical reactions. However, further optimization of such preservation strategies is now seen to be restricted. Long-term preservation calls for much lower temperatures and requires the tissue to withstand the rigors of heat and mass transfer during protocols designed to optimize cooling and warming in the presence of cryoprotective agents. It is now accepted that with current methods of cryopreservation, uncontrolled ice formation in structured tissues and organs at subzero temperatures is the single most critical factor that severely restricts the extent to which tissues can survive procedures involving freezing and thawing. In recent years, this major problem has been effectively circumvented in some tissues by using ice-free cryopreservation techniques based upon vitrification. Nevertheless, despite these promising advances there remain several recognized hurdles to be overcome before deep-subzero cryopreservation, either by classic freezing and thawing or by vitrification, can provide the much-needed means for biobanking complex tissues and organs for extended periods of weeks, months, or even years. In many cases, the approaches outlined here, including new underexplored paradigms of high-subzero preservation, are novel and inspired by mechanisms of freeze tolerance, or freeze avoidance, in nature. Others apply new bioengineering techniques such as nanotechnology, isochoric pressure preservation, and non-Newtonian fluids to circumvent currently intractable problems in cryopreservation.

Ex vivo evaluation of the efficacy of canine fresh-frozen plasma thawed using a microwave plasma defroster

BACKGROUND

Commercial microwave plasma defrosters (MPDs) are used globally in human medicine to safely thaw fresh-frozen plasma (FFP), but this technology has never been tested in a veterinary setting. This study was undertaken to assess the efficacy of a commercial MPD for the rapid thawing of canine FFP.

STUDY DESIGN

Twenty-three units (twelve 120 mL and eleven 240 mL) of canine FFP were thawed using an MPD. Time-to-thaw and pre- and postthawing temperatures of the units were measured. Clotting factor activities (factors II, V, VII, VIII, IX, X, and von Willebrand factor), fibrinogen concentrations, prothrombin times, and activated partial thromboplastin times were measured.

KEY FINDINGS

The evaluated MPD effectively thaws plasma quickly for both 120 mL units (2.7 ± 0.08 min) and 240 mL units (3.9 ± 0.15 min) while maintaining clinically relevant activities of clotting factors and fibrinogen concentration. While some measurements of factor VIII activity fell below the reference interval, none fell below 40%. One 240 mL unit had von Willebrand factor activity <70%. There was no evidence of excessively heated plasma to indicate a safety concern.

SIGNIFICANCE

The MPD evaluated in this study provides a useful means to rapidly thaw canine FFP for correction of factor-deficient coagulopathy.

Thawing of Pooled, Solvent/Detergent-Treated Plasma octaplasLG: Validation Studies Using Different Thawing Devices

BACKGROUND

The aim of this study was to perform validation of the thawing process for solvent/detergent-treated plasma octaplasLG® using different thawing devices. Optimized settings for temperature and thawing time should be defined based on the results of both temperature measurements and extensive biochemical characterization studies.

METHODS

octaplasLG units were thawed using water bath systems (i.e. MB-13A, QuickThaw® DH4), dry tempering systems (i.e. plasmatherm, SAHARA-III), and microwave oven (i.e. transfusio-therm® 2000). Optimized thawing conditions were defined. Subsequently, using the selected thawing conditions, octaplasLG units were thawed and tested on product release parameters.

RESULTS

The fastest thawing was observed for the microwave oven. All octaplasLG units thawed by different devices and optimized thawing conditions were clear and free of solid and gelatinous particles, indicating no protein denaturation or overheating. In addition, no significant differences were found in the coagulation and inhibition activity and hemostatic potency of octaplasLG when thawed by the different devices tested. All parameters after thawing were within the product release specification levels.

CONCLUSION

Our study demonstrated that octaplasLG can be thawed using all above listed devices without any negative influence on the plasma quality, presupposed that optimized settings defined for this plasma product are used.

What is new in the blood bank for trauma resuscitation

PURPOSE OF REVIEW

The aim of the present review was to describe recent changes in blood banking thinking, practice, and products that affect trauma care.

RECENT FINDINGS

Prompt balanced hemostatic resuscitation of major hemorrhage from trauma improves outcome and reduces blood use. New blood processes and products can help deliver appropriate doses of procoagulant plasma and platelets quicker and more safely. New processes include holding larger inventories of thawed plasma with risk of wastage and rapid plasma thawers. New products in the blood bank include group A or group A low-titer B thawed plasma and AB or A liquid (never-frozen) plasma for resuscitation, prepooled cultured whole blood-derived platelets in plasma, and prepooled cryoprecipitate in varying pool sizes. Single-donor apheresis or pooled whole blood-derived platelets in additive solution, designed to reduce plasma-related transfusion reactions, are also increasingly available but are not an appropriate blood component for hemorrhage control resuscitation because they reduce the total amount of administered plasma coagulation factors by 10%.

SUMMARY

Early initiation of balanced massive transfusion protocols leading to hemostatic resuscitation is lifesaving. Changing blood product availability and composition will lead to higher complexity of massive transfusion. It is critical that anesthesiologists understand the composition of the available new blood products to use them correctly.

International normalised ratio normalisation in patients with coumarin-related intracranial haemorrhages--the INCH trial: a randomised controlled multicentre trial to compare safety and preliminary efficacy of fresh frozen plasma and prothrombin complex--study design and protocol

BACKGROUND

Intracerebral haemorrhage is the most feared complication in patients who are on treatment with vitamin K antagonists. Vitamin K antagonist related intracerebral haemorrhage occurs in about 10% of patients. Intracerebral haemorrhage has the worst prognosis of all subtypes of stroke including spontaneous intracerebral haemorrhage, and a mortality rate of up to about 65%. The higher rate of haematoma expansion due to rebleeding is thought to be responsible for the higher mortality. Current international treatment recommendations include fresh frozen plasma and prothrombin complex concentrate. It is known that these substances lower the international normalised ratio, and thus it is assumed that normalisation of coagulopathy may lead to haemostasis and reduction of rebleeding. However, the issue of whether to use fresh frozen plasma or prothrombin complex concentrate for urgent reversal of vitamin K antagonists is unresolved: safety and efficacy of these treatments have never been studied in a randomised controlled trial. Our questions are: how effective are the two substances in normalisation of the international normalized ratio? How feasible is it to apply either of these treatments in an acute situation? What is the safety profile of each of these substances? Is there a difference in haematoma growth and clinical outcome?

METHOD

We designed a prospective, randomised, controlled multicentre trial to compare biological efficacy and safety of fresh frozen plasma and prothrombin complex concentrate in vitamin K antagonist related intracerebral haemorrhage. The study is observer-blinded for laboratory, neuroradiological, and clinical outcomes. Patients will be included if a computed tomography scan shows an intraparenchymal or subdural haematoma within 12 h after onset of symptoms, if the patient is on treatment with vitamin K antagonists, and the international normalized ratio is ≥2. Primary endpoint is the normalisation of the international normalized ratio (≤1·2) within three-hours after the start of antagonising therapy. Main exclusion criteria are secondary intracerebral haemorrhage, other known coagulopathies, and known acute ischaemic events.

DISCUSSION

We discuss the rationale of our trial on the basis of the current recommendations and specific aspects of trial design as, time window, choice of endpoints, dosing of fresh frozen plasma and prothrombin complex concentrate, monitoring and analysis of safety parameters, and rescue treatment.

CONCLUSION

This will be the first prospective trial comparing fresh frozen plasma and prothrombin complex concentrate in the indication of vitamin K antagonist related intracerebral hemorrhage. Recruitment of subjects started in August 2009. Until now, 19 patients have been included.

A biochemical quality study of a pharmaceutically licenced coagulation active plasma (Octaplas) thawed by the SAHARA-III dry tempering system compared to the regular use of a water bath

BACKGROUND AND OBJECTIVES

The most common way to thaw frozen coagulation-active plasma products for transfusion is the use of a water bath with good circulation at 30-37 degrees C. The aim of this study was to perform an extensive biochemical characterization of the pharmaceutically licenced solvent/detergent-treated plasma, Octaplas, thawed using the SAHARA-III dry tempering system from the company Sarstedt GmbH, Austria. A regular water bath was used in parallel for comparison.

MATERIALS AND METHODS

Six batches Octaplas with different blood groups were thawed in a water bath or using the SAHARA-III dry tempering system in parallel. Thawed plasma was investigated on screening tests for blood coagulation, as well as on the activities of important coagulation factors and protease inhibitors. In addition, markers of activated coagulation and fibrinolysis were tested and von Willebrand factor multimeric analysis was performed.

RESULTS

There were neither significant differences in the blood coagulation parameters, coagulation factors, protease inhibitors, nor of markers of activated coagulation and fibrinolysis when Octaplas thawed by the two different methods was tested. The von Willebrand factor analyses showed no influence on the overall profile of the multimeric pattern when using the SAHARA-III dry tempering system.

CONCLUSION

Octaplas can be thawed using the SAHARA-III dry tempering system without any negative influences on the demonstrated quality of this product. The SAHARA-III dry tempering system enables standardized thawing and warming procedure. Furthermore, tempering of Octaplas in the emergency unit or operating theatre, where no water baths can be utilized, is safe and can be fully endorsed.

Thawing Procedures and the Time Course of Clotting Factor Activity in Fresh-Frozen Plasma: A Controlled Laboratory Investigation

BACKGROUND

In this study, we evaluated the effects of the thawing process of 2 commercially available devices on the activity of clotting factors, inhibitors and activation markers of the hemostatic system in fresh-frozen plasma (FFP). In an experimental procedure, FFP was thawed under running warm water at 42 degrees C.

METHODS

Plasma of 20 healthy donors was sampled, separated, and distributed in 3 plasma bags. Within 2 h after sampling plasma bags was frozen at a temperature of -30 degrees C to -40 degrees C and stored for at least 8 wk. After sampling (baseline) as well as immediately and 1, 2, 4, and 6 h after thawing, the activity of FV, FVII, FVIII, fibrinogen, fibrin monomers (FM), d-dimers (DD), alpha2-antiplasmin (alpha2-AP), and protein S (PS) was determined from each plasma bag.

RESULTS

From 1 h to 6 h after thawing, no significant differences in the activity of the investigated coagulation markers dependent on the thawing procedure were found. However, immediately after thawing and independent of the thawing procedure, the activity of FVII was significantly decreased (P < 0.01), whereas FM were significantly increased (P = 0.001).

CONCLUSION

The thawing procedures studied exhibited no significant influence on activity and stability of the investigated markers of coagulation over the study period. The decreased activity of FVII and the clinical significance of the increase in FM require further research.