Supernatant Potassium Levels Research Articles

The compound effect of irradiation and familial pseudohyperkalemia on potassium leak from red blood cells.

Familial pseudohyperkalemia (FP) is a rare asymptomatic condition characterized by an increased rate of potassium leak from red blood cells (RBC) on refrigeration. Gamma irradiation compromises RBC membrane integrity and accelerates potassium leakage. Here, we compared the effect of irradiation, applied early or late in storage, on FP versus non-FP RBC. Five FP and 10 non-FP individuals from the National Institute for Health Research Cambridge BioResource, UK, and three FP and six non-FP individuals identified by Australian Red Cross Lifeblood consented to the study. Blood was collected according to standard practice in each center, held overnight at 18-24°C, leucocyte-depleted, and processed into red cell concentrates (RCC) in Saline Adenine Glucose Mannitol. On Day 1, RCC were split equally into six Red Cell Splits (RCS). Two RCS remained non-irradiated, two were irradiated on Day 1 and two were irradiated on Day 14. RBCs were tested over cold storage for quality parameters. As expected, non-irradiated FP RCS had significantly higher supernatant potassium levels than controls throughout 28 days of storage (p < .001). When irradiated early, FP RCS released potassium at similar rates to control. When irradiated late, FP RCS supernatants had higher initial post-irradiation potassium concentration than controls but were similar to controls by the end of storage (14 days post-irradiation). No other parameters studied showed a significant difference between FP and control. FP does not increase the rate of potassium leak from irradiated RBCs. Irradiation may cause a membrane defect similar to that in FP RBCs.

Rapid bedside rejuvenation of red blood cell with an autologous cell salvage device.

During storage, red blood cells (RBCs) undergo physicochemical changes which affect the quality, function, and invivo survival of transfused packed RBCs (pRBC). Changes include decreased 2,3-diphosphoglycerate (2,3-DPG) levels, decreased ATP, changes in mechanical properties and oxidative injury. RBC rejuvenation is a method used to increase levels of 2,3-DPG and ATP in pRBCs. This process requires incubating the pRBCs with a rejuvenation solution and subsequent washing. Standard blood bank protocols using the COBE 2991 Cell Processor require several hours of preparation. The objective of this study was to verify if a bedside protocol for rejuvenating pRBC and washing with the Sorin Xtra autologous cell salvage system could be used. Outdated pRBC units were obtained and rejuvenated in a model operating suite using a dry air incubator for 1h at 37°C. Six units of pRBCs were pre-diluted with saline (1000ml) and six units were not pre-diluted with saline. All units were washed with normal saline (1000ml) using an apheresis-design cell salvage device in manual mode and wash volume set to 3000ml. Samples were collected and analyzed for standard RBC quality parameters at baseline and post-wash. Total pRBC wash efficiency was 94% ± 12% at a final hematocrit of 67.7±5.9% while maintaining post-wash hemolysis 0.24±0.12 %. Pre-dilution prior to washing did not confer statistically significant differences in final RBC quality parameters with the notable exceptions of calculated hemolysis and supernatant potassium levels (P<0.05). The washing process can be completed within 10min. The post-wash RBC parameters are appropriate for immediate transfusion to patients.

Bringing Packed Red Blood Cells to the Point of Combat Injury: Are We There Yet?

ObjectiveHemorrhage is the leading cause of injury-related prehospital mortality. We investigated worst-case scenarios and possible requirements of the Turkish military. As we plan to use blood resources during casualty transport, the impact of transport-related mechanical stress on packed red blood cells (PRBCs) was analyzed.Materials and MethodsThe in vitro experiment was performed in the environmental test laboratories of ASELSAN®. Operational vibrations of potential casualty transport mediums such as Sikorsky helicopters, Kirpi® armored vehicles, and the NATO vibration standard MIL-STD-810G software program were recorded. The most powerful mechanical stress, which was created by the NATO standard, was applied to 15 units of fresh (≤7 days) and 10 units of old (>7 days) PRBCs in a blood cooler box. The vibrations were simulated with a TDS v895 Medium-Force Shaker Device. On-site blood samples were analyzed at 0, 6, and 24 h for biochemical and biomechanical analyses.ResultsThe mean (±standard deviation) age of fresh and old PRBCs was 4.9±2.2 and 32.8±11.8 days, respectively. Six-hour mechanical damage of fresh PRBCs was demonstrated by increased erythrocyte fragmentation rates (p=0.015), hemolysis rates (p=0.003), and supernatant potassium levels (p=0.003) and decreased hematocrit levels (p=0.015). Old PRBC hemolysis rates (p=0.015), supernatant potassium levels (p=0.015), and supernatant hemoglobin (p=0.015) were increased and hematocrit levels were decreased (p=0.015) within 6 h. Two (13%) units of fresh PRBCs and none of the old PRBCs were eligible for transfusion after 6 h of mechanical stress.ConclusionWhen an austere combat environment was simulated for 24 h, fresh and old PRBC hemolysis rates were above the quality criteria. Currently, the technology to overcome this mechanical damage does not seem to exist. In light of the above data, a new national project is being performed.

Quality of red cells after combination of prion reduction and treatment with the intercept system for pathogen inactivation.

The pathogen inactivation (PI) INTERCEPT Blood System for Red Blood Cells utilises amustaline (S-303) to inactivate a broad range of pathogens in red cell concentrates (RCC). The aim of this study was to investigate the effect on red cell quality of INTERCEPT treatment with and without prion reduction. Five pools of five RCC each were prepared. These were split and treated as follows: (i) stored at 2-6 °C for 18 h, (ii) stored at 18-24 °C for 18 h, (iii) PI-treated, (iv) PI-treated then prion reduced and (v) prion reduced then PI-treated. Prior to storage, PI-treated RCC underwent an exchange step to remove S-303 and other breakdown products. Components were tested throughout 35 days of storage for in vitro parameters of red cell quality. All RCC met specification for volume and haemoglobin content. Haemolysis, microvesicle formation, supernatant potassium and deformability were lower and ATP levels higher in PI-treated units when compared with control units. The effect of prion reduction in addition to PI treatment was minimal in all parameters tested except haemolysis, which was increased in units prion-reduced after being PI-treated. The PI-treatment process did not increase red cell haemolysis or decrease ATP levels over storage. The lower haemolysis and supernatant potassium levels in treated RCC compared with control RCC were attributed to the exchange step. The effects of combining PI treatment and prion reduction were not more than additive when prion reduction precedes PI treatment.

Comparative study of automated cryopreservation of red blood cells

BackgroundStrategic blood reserves are an important component in meeting blood needs and this can be accomplished through the establishment of a frozen blood program. MethodsOne hundred units of packed RBC were glycerolized using the Haemonetics ACP 215 automated cell processor and placed in a −86 °C deep freezer for freezing and storage. Product weight, hematocrit, RBC count, WBC count and hemoglobin were recorded prior to freezing. Twenty five bags were thawed and deglycerolized after every three months starting at one year from the date of first glycerolization In addition to the earlier parameters the bags were assessed for supernatant osmolality, pH, supernatant hemoglobin, ATP levels and supernatant potassium and from these red cell recovery, percentage hemolysis, supernatant glycerol and red cell viability were estimated. All tests were repeated at the end of 7 and 14 days. ResultsThe mean red cell recovery was found to be 86.12% on Day 0 and 84% on Day 14. All the bags showed residual glycerol and pH within the acceptable limits upto Day 14. Percentage hemolysis, Mean ATP levels and mean supernatant potassium levels were within acceptable limits upto Day 14. All the units were sterile upto Day 14. ConclusionThe data in this study showed that the red cells which were glycerolized using the automated platform ACP 215, frozen at −80 °C for more than a year and deglycerolized again using the ACP 215 had excellent viability while being stored at 4 °C during the 14 days of post-thaw storage.

Rejuvenation of ATP during storage does not reverse effects of the hypothermic storage lesion

Hypothermic storage (HS) of red blood cells (RBCs) leads to a progressive deterioration of cell quality. Mitigating these deleterious changes could allow maintenance or even an improvement of RBC in vitro quality. The aim was to determine the effect of a cold rejuvenation treatment of RBCs and in particular to assess the connection between ATP levels, RBC deformability, and morphology during RBC storage. A pool-and-split design of leukoreduced CPD-saline-adenine-glucose-mannitol-packed RBC units was used to generate three groups: untreated controls, sham-treated units, and units treated with a cold (1-6 °C) rejuvenation solution on Day 28, 35, or 42 of cold storage. Units were followed until Day 49 of storage and assessed for ATP concentration, morphology, deformability, and other in vitro quality variables including hemolysis, pH, and supernatant potassium levels. At every treatment time, rejuvenation was associated with a significant increase in intracellular ATP (p < 0.01). On Day 28, rejuvenation was accompanied by a significant decrease in deformability 1 week after treatment (p < 0.01). Rejuvenation on Day 28, but not Day 35 or 42, was also associated with a significant change in morphology (p < 0.01). Of the in vitro quality variables measured, most changed during cold storage, but differences among treatment groups were not observed. The results of our study demonstrate a cold rejuvenation of RBCs during HS increases intracellular ATP, but that this change does not ameliorate, or exacerbate, the metabolic or biochemical symptoms of the storage lesion.

Quality of red blood cells washed using the ACP 215 cell processor: assessment of optimal pre‐ and postwash storage times and conditions

Washing of red blood cell concentrates (RCCs) is required for potassium-sensitive transfusion recipients, including neonates in need of large-volume transfusions. When open, nonsterile washing systems are used, postwash outdate time is limited to 24 hours, often leading to problems providing the component to the patient before expiry. A closed, automated cell processor, the ACP 215 from Haemonetics Corporation, was used to wash RCCs and determine optimal pre- and postwash storage times. Two postwash storage solutions, additive solution (AS)-3 and saline-adenine-glucose-mannitol (SAGM), were compared. The in vitro quality of leukoreduced RCCs, prepared from citrate-phosphate-dextrose-anticoagulated whole blood, was determined postwash and compared to existing guidelines for RCC quality (hemoglobin content, hematocrit, and hemolysis) and predetermined criteria for ATP and supernatant potassium levels. A criterion for visual hemolysis was also applied. The prewash storage time, postwash storage time, and the postwash resuspension solution all contributed to RCC quality postwash. Levels of hemolysis were greater when washed RCCs were resuspended in SAGM (p = 0.01), while AS-3 proved worse at maintaining ATP levels postwash (p < 0.01). Immediately postwash, all units had supernatant K+ levels below the detection limit of the instrument (<1 mmol/L), but these increased to above acceptable levels within 14 days. Based on all acceptance criteria, a maximum 14-day prewash storage period and 7-day postwash storage period in SAGM preservative was found to be optimal. The longer outdate time postwashing should help lessen challenges in providing components to patients before expiry.

Effect of X‐irradiation on the quality of red cell concentrates

The irradiation of blood components is used to inactivate T-lymphocytes to prevent transfusion-associated graft-versus-host (GVH) disease in susceptible recipients. X-irradiation can be used as an alternative to gamma irradiation and does not involve the use of a radioactive source. This study investigated the effect of X-irradiation on the quality of various red cell concentrates (RCC). Whole blood units were processed into RCC in additive solution (SAG-M) or RCC in plasma suitable for intra-uterine (IUT) or neonatal exchange transfusion. RCC-SAG-M were irradiated at day 14 and sampled before and 0, 7 and 14 days following irradiation. RCC-IUT and RCC-Exchange were irradiated on day 4 and sampled before and 0 and 24 h following irradiation. Extracellular potassium levels and free plasma haemoglobin (haemolysis) were compared in X or gamma-irradiated units during storage. X-irradiation of RCC in SAG-M, or RCC for IUT or Exchange resulted in haemolysis comparable with gamma irradiation and levels were below the current UK/CE limit of 0.8% at the end of shelf life. X-irradiation of RCC-SAG-M or RCC-IUT with haematocrit of 75% and 85% resulted in potassium leakage comparable with gamma-irradiation. However, X-irradiation of RCC for neonatal exchange transfusion showed statistically significantly higher supernatant potassium levels after 24 h than gamma irradiation, although this difference is considered to be clinically insignificant. X-irradiation of RCC in SAG-M or IUT or RCC in plasma suitable for neonatal exchange transfusion resulted in acceptable levels of haemolysis and potassium leakage compared with the current process of gamma irradiation.

Double red cell concentrates -in vitro quality after delayed refrigeration

Automated collection of red cell concentrates (RCC) presents a number of potential advantages to donors, blood services and recipients, and allows the collection of finished components from sites that are remote from a blood centre. However, data are lacking on how long the collected RCC may be stored at ambient temperature prior to their final storage at 4 °C. In this study, the Haemonetics Cymbal device was used to collect RCC using citrate, phosphate and dextrose (CPD-50) anticoagulant. A total of 10 procedures each yielded two leucodepleted RCC in saline, adenine, glucose and mannitol (SAGM) additive solution. One of each pair of RCC was kept warm in an insulated transport bag for 8 h and the other for 6 h. In vitro assessments of the quality of the RCC were made during subsequent 42-day storage of the RCC at 2-6 °C, and compared with reference data. All collected RCC were within UK and European limits for volume, haematocrit and haemoglobin content. Haemolysis was within specification at Day 42 and was no different in RCC held warm for 6 or 8 hours, but tended to be higher than reference data from whole blood derived RCC. ATP, 2,3 DPG and supernatant potassium levels were all similar in RCC held warm for 6 or 8 hours and reference data. We conclude that the Cymbal device may be used to collect two RCC in SAGM, and the in vitro assessment indicates that RCC may be stored without refrigeration for up to 8 h following collection, prior to final storage at 4 °C.

Evaluation of in vivo and in vitro Quality of Apheresis‐Collected RBC Stored for 42 Days

New technological developments make it possible to collect red blood cells (RBCs) by apheresis, which allows for better product consistency and has the potential for improved RBC quality. The purpose of these studies was to evaluate the quality and consistency of units of RBCs collected by apheresis using the MCS+(R) machine (Haemonetics Corp., Braintree, Mass., USA). Two studies were performed. In study 1 (n = 10), using containers and CP2D/AS-3 solutions from Medsep Corp. (Covina, Calif. USA), one-unit apheresis RBCs were compared to manually collected RBCs in a random crossover design. In study 2 (n = 12), 6 subjects had one unit collected, while the remaining 6 subjects had two units of RBCs collected with comparison to previously manually collected RBCs from the same donors. Haemonetics containers and solutions were used in study 2. Low RBC volume variability was found for the apheresis collections with a standard deviation of only 6 ml difference between actual and target volumes. Combining the data from the two studies (n = 21 pairs), at 42 days of storage, the apheresis units showed slightly lower hemolysis (0.44+/-0.26 vs. 0.61+/-0.50%), lower supernatant potassium levels (50+/-3 vs. 53+/-3 mEq/l), and improved tolerance to osmotic shock (47+/-3 vs. 49+/-3%) as compared to manual units (p < 0.05). There was no statistically significant difference in RBC ATP (3.0+/-0.6 vs. 2.9+/-0.5 micromol/g Hb) or in 24-hour percent recoveries (81+/-6 for apheresis vs. 81+/-4% for apheresis red cells). Apheresis RBC quality was not affected by the manufacturer (Haemonetics vs. Medsep) of solutions and containers. RBC units collected by apheresis demonstrated low variability in volume of RBC mass collected, and showed similar RBC properties as compared to manually collected RBCs after processing and after 42 days of storage.

Evaluation of in vivo and in vitro Quality of Apheresis-Collected RBC Stored for 42 Days

Background and Objectives: New technological developments make it possible to collect red blood cells (RBCs) by apheresis, which allows for better product consistency and has the potential for improved RBC quality. The purpose of these studies was to evaluate the quality and consistency of units of RBCs collected by apheresis using the MCS+® machine (Haemonetics Corp., Braintree, Mass., USA). Materials and Methods: Two studies were performed. In study 1 (n = 10), using containers and CP2D/AS-3 solutions from Medsep Corp. (Covina, Calif. USA), one-unit apheresis RBCs were compared to manually collected RBCs in a random crossover design. In study 2 (n = 12), 6 subjects had one unit collected, while the remaining 6 subjects had two units of RBCs collected with comparison to previously manually collected RBCs from the same donors. Haemonetics containers and solutions were used in study 2. Results: Low RBC volume variability was found for the apheresis collections with a standard deviation of only 6 ml difference between actual and target volumes. Combining the data from the two studies (n = 21 pairs), at 42 days of storage, the apheresis units showed slightly lower hemolysis (0.44±0.26 vs. 0.61±0.50%), lower supernatant potassium levels (50±3 vs. 53±3 mEq/l), and improved tolerance to osmotic shock (47±3 vs. 49±3%) as compared to manual units (p < 0.05). There was no statistically significant difference in RBC ATP (3.0±0.6 vs. 2.9±0.5 μmol/g Hb) or in 24-hour percent recoveries (81±6 for apheresis vs. 81±4% for apheresis red cells). Apheresis RBC quality was not affected by the manufacturer (Haemonetics vs. Medsep) of solutions and containers. Conclusions: RBC units collected by apheresis demonstrated low variability in volume of RBC mass collected, and showed similar RBC properties as compared to manually collected RBCs after processing and after 42 days of storage.

Effect of supernatant potassium-level on cardiac activity in quantitative tissue culture.

INADEQUATE functional ‘survival’ of hearts cultured in supernatant containing serum with a high potassium-level from lysed red cells led us to investigate the effects of supernatant potassium-levels on the electrical activity of 1,222 hearts in quantitative tissue culture. The criterion for ‘adequate survival’ is an ability to produce potentials of at least 0.02 mV. during a minimum of three periods of observation per day (8 a.m., 1 p.m. and 5 p.m.). The apparatus, etc., is described in previous papers1. The supernatants are 0.25 per cent solutions of human serum protein in balanced salt solutions—however, they differ in potassium-level. The ‘adequate survival’ time is given to the nearest day using the smallest figure in cases of doubt.