Use of a K+-adsorption filter for the massive transfusion of irradiated red blood cells in a child

Transfusion-Associated Hyperkalemic Cardiac Arrest in Neonatal, Infant, and Pediatric Patients

Red blood cell (RBC) transfusions are a life-saving intervention, with nearly 14 million RBC units transfused in the United States each year. However, the safety and efficacy of this procedure can be influenced by variations in the collection, processing, and administration of RBCs. Procedures or manipulations that increase potassium (K⁺) levels in stored blood products can also predispose patients to hyperkalemia and transfusion-associated hyperkalemic cardiac arrest (TAHCA). In this mini review, we aimed to provide a brief overview of blood storage, the red cell storage lesion, and variables that increase extracellular [K⁺]. We also summarize cases of TAHCA and identify potential mitigation strategies. Hyperkalemia and cardiac arrhythmias can occur in pediatric patients when RBCs are transfused quickly, delivered directly to the heart without time for electrolyte equilibration, or accumulate extracellular K⁺ due to storage time or irradiation. Advances in blood banking have improved the availability and quality of RBCs, yet, some patient populations are sensitive to transfusion-associated hyperkalemia. Future research studies should further investigate potential mitigation strategies to reduce the risk of TAHCA, which may include using fresh RBCs, reducing storage time after irradiation, transfusing at slower rates, implementing manipulations that wash or remove excess extracellular K⁺, and implementing restrictive transfusion strategies.

Supernatant reduction of stored gamma-irradiated red blood cells minimizes potentially harmful substances present in transfusion aliquots for neonates

BACKGROUND

In neonate transfusion, the use of a dedicated red blood cell (RBC) unit decreases donor exposure. A separate safety measure involves gamma irradiation of the RBCs to abrogate the possibility of transfusion-associated graft-versus-host disease. However, in combination, storage of gamma-irradiated RBCs leads to accumulation of potentially harmful substances in the supernatant.

STUDY DESIGN AND METHODS

For this study, RBCs were pooled and split into three study arms. Centrifugation or gravity was used to pack RBCs of matched units thereby reducing the amount of supernatant that would be present in neonate transfusion aliquots; these were compared to matched control units. Supernatant measurements of potassium, hemoglobin (Hb), RBC microvesicle (RMV) content, and mannitol were made in aliquots prepared weekly up to 21 days after gamma irradiation. RBC morphology and osmotic fragility were also assessed to determine if supernatant reduction methods affected the storage lesion.

RESULTS

Potassium and mannitol were significantly decreased in transfusion aliquots prepared with either of the supernatant reduction methods. On Day 21, potassium levels from supernatant-reduced aliquots were below those of Day 7 control aliquots. A decrease in free Hb was only detected on Day 21 in centrifuged aliquots. RMVs were significantly reduced in centrifuged aliquots and significantly increased in gravity-settled aliquots. The only measurable effect on storage lesion was a small increase in osmotic fragility of the RBCs subjected to supernatant reduction.

CONCLUSION

Supernatant reduction by centrifugation effectively reduces potassium, mannitol, and RMVs in aliquots from gamma-irradiated RBCs stored up to 21 days.

Hyperkalemia caused by rapid red cell transfusion and the potassium absorption filter

We report a case of transient hyperkalemia during hysterectomy after cesarean section, due to preoperatively undiagnosed placenta accreta that caused unforeseen massive hemorrhage and required rapid red cell transfusion. Hyperkalemia-induced by rapid red cell transfusion is a well-known severe complication of transfusion; however, in patients with sudden massive hemorrhage, rapid red cell transfusion is necessary to save their life. In such cases, it is extremely important to monitor serum potassium levels. For an emergency situation, a system should be developed to ensure sufficient preparation for immediate transfusion and laboratory tests. Furthermore, sufficient stock of preparations to treat hyperkalemia, such as calcium preparations, diuretics, glucose, and insulin is required. Moreover, a transfusion filter that absorbs potassium has been developed and is now available for clinical use in Japan. The filter is easy to use and beneficial, and should be prepared when it is available.

Transfusion of irradiated red blood cell units with a potassium adsorption filter: A randomized controlled trial

BACKGROUND

The irradiation of red blood cells (RBCs) causes damage of the RBC membrane with increased potassium (K) leak during storage compared with nonirradiated RBC units of similar age. A previous in vitro study showed a mean reduction of K of 94 ± 5% with a potassium adsorption filter (PAF).

STUDY DESIGN AND METHODS

A prospective, single-center, nonblinded, randomized controlled trial (RCT) was designed to evaluate the safety and efficacy of transfusing irradiated RBC units with the PAF. Patients 18 years of age or older who received irradiated RBC units due to chemotherapy-induced anemia were randomly assigned to receive irradiated RBC units with the PAF (PAF group) or with the standard blood infusion set (control group). Primary outcome measures were safety and efficacy of the PAF (absolute change in hemoglobin [Hb] and K, respectively, in patient's blood values after transfusing the irradiated RBC units with or without the PAF).

RESULTS

A total of 63 irradiated RBC units were transfused to 17 patients in the control group, and a total of 56 irradiated RBC units were transfused to 13 patients in the PAF group. The absolute change of Hb (9.3 ± 6.3 g/L vs. 8.1 ± 5.8 g/L; p = 0.3) and the absolute change of K (-0.01 ± 0.4 mmol/L vs. -0.01 ± 0.3 mmol/L; p = 0.2) were comparable between the two groups of the trial.

CONCLUSION

The transfusion of 1 irradiated RBC unit with the PAF was as safe and efficacious as the transfusion of 1 irradiated RBC unit with the standard blood infusion set in patients with chemotherapy-induced anemia.

Hemolysis of red blood cells after cell washing with different automated technologies: clinical implications in a neonatal cardiac surgery population

BACKGROUND

In subsets of pediatric cardiac surgery patients, red blood cells (RBCs) are often washed to reduce extracellular potassium (K) to avoid hyperkalemia, but mechanical manipulation and time delay in issuing washed products may increase hemolysis and K. This study's purpose was to evaluate the quality of washed RBCs with regard to hemolysis and extracellular K using different cell washers as a function of postprocessing time.

STUDY DESIGN AND METHODS

Fresh (<4 days old) RBCs were washed on COBE 2991 blood cell processors (Model 1 and Model 2) or the Fresenius Continuous AutoTransfusion System (CATS), and K and hemolysis index (HI) were analyzed. Academic pediatric hospitals were surveyed to ascertain practice trends regarding indications for washing, washing device, and expiration time for washed RBCs.

RESULTS

K concentration at 24 hours for units washed with the COBE devices met or exceeded prewash values. At 12 hours, there was a significant difference (p < 0.001) in K concentration between all devices, with the CATS maintaining the lowest K concentration. HI increased immediately after wash on all devices and showed a significant difference between the COBE devices and CATS at times of more than 6 hours (p < 0.01). At storage times beyond 4 hours, hemoglobin exceeded 100 mg/dL on the COBE Model 1. Survey of pediatric hospitals indicated that COBE devices are commonly used, and storage time after washing was 12 hours or more in blood banks queried.

CONCLUSIONS

Hemolysis levels vary among different cell washers. Decreasing the expiration time of units after washing may be warranted.

Insulin therapy in divided doses coupled with blood transfusion versus large bolus doses in patients at high risk for hyperkalemia during liver transplantation

OBJECTIVE

To assess the effectiveness of an insulin regimen in divided doses designed to target risk factors of hyperkalemia in patients undergoing liver transplantation.

DESIGN

Retrospective comparison of the divided insulin dose regimen with a conventional large-bolus insulin method during liver transplantation.

SETTING

University-based, academic, tertiary center.

PARTICIPANTS

Adult patients whose baseline potassium levels were >/=4.0 mmol/L and received insulin therapy during liver transplantation at the authors' medical center between January 2004 and April 2007.

INTERVENTIONS

Insulin was administered either in divided doses (1-2 units) for each unit of red blood cells transfused or in a large-bolus in patients at high risk for hyperkalemia during liver transplantation.

MEASUREMENTS AND MAIN RESULTS

Among 717 patients who underwent liver transplantation, 50 patients received insulin in divided doses, and 101 patients received a large-bolus of insulin. Perioperative characteristics were comparable except for higher insulin doses in the large-bolus group. The divided insulin regimen was associated with significantly lower mean potassium levels within 2 hours before reperfusion of the graft compared with the conventional group (p < 0.005). The mean glucose levels in the divided group were significantly lower in both the pre- and postreperfusion periods than in the conventional group (p < 0.05 to <0.001).

CONCLUSIONS

The divided insulin dose regimen that specifically targets the risk factors for prereperfusion hyperkalemia is associated with significantly lower prereperfusion potassium and pre- and postreperfusion glucose levels and provides a useful alternative to the conventional large-bolus method in management of intraoperative hyperkalemia during liver transplantation.

Anesthetic management of hepatic transplantation

PURPOSE OF REVIEW

The present review describes new trends and ongoing controversies in the anesthetic care of liver transplant recipients.

RECENT FINDINGS

Recent studies have improved our knowledge of conditions increasing perioperative risk, such as portopulmonary hypertension and renal failure. Improved surgical and anesthetic management has reduced intraoperative blood loss, as more studies identify an independent association between blood transfusion and poor outcome. New concepts in the coagulopathy of liver failure are emerging, with clear implications for clinical practice, including greater awareness of the risks of intraoperative thromboembolism. Less invasive intraoperative hemodynamic monitoring has been advocated, as has wider use of transoesophageal echocardiography. Early extubation is becoming more routinized.

SUMMARY

Anesthetic management still varies widely between liver transplant centers with little data to indicate best practice. Future research should focus on fluid replacement, prevention and treatment of coagulopathy, care of the acutely ill patient and the safety and benefits of early extubation.

Cardiac arrests associated with hyperkalemia during red blood cell transfusion: a case series

BACKGROUND

Transfusion-associated hyperkalemic cardiac arrest is a serious complication of rapid red blood cell (RBC) administration. We examined the clinical scenarios and outcomes of patients who developed hyperkalemia and cardiac arrest during rapid RBC transfusion.

METHODS

We retrospectively reviewed the Mayo Clinic Anesthesia Database between November 1, 1988, and December 31, 2006, for all patients who developed intraoperative transfusion-associated hyperkalemic cardiac arrest.

RESULTS

We identified 16 patients with transfusion-associated hyperkalemic cardiac arrest, 11 adult and 5 pediatric. The majority of patients underwent three types of surgery: cancer, major vascular, and trauma. The mean serum potassium concentration measured during cardiac arrest was 7.2 +/- 1.4 mEq/L (range, 5.9-9.2 mEq/L). The number of RBC units administered before cardiac arrest ranged between 1 (in a 2.7 kg neonate) and 54. Nearly all patients were acidotic, hyperglycemic, hypocalcemic, and hypothermic at the time of arrest. Fourteen (87.5%) patients received RBC via central venous access. Commercial rapid infusion devices (pumps) were used in 8 of 11 (72.7%) of the adult patients, but RBC units were rapidly administered (pressure bags, syringe pumped) in all remaining patients. Mean resuscitation duration was 32 min (range, 2-127 min). The in-hospital survival rate was 12.5%.

CONCLUSION

The pathogenesis of transfusion-associated hyperkalemic cardiac arrest is multifactorial and potassium increase from RBC administration is complicated by low cardiac output, acidosis, hyperglycemia, hypocalcemia, and hypothermia. Large transfusion of banked RBCs and conditions associated with massive hemorrhage should raise awareness of the potential for hyperkalemia and trigger preventative measures.

The changing pattern of anesthesia, 1954-2004: a review based on the content of theCanadian Journal of Anesthesia in its first half-century

PURPOSE

In order to review changes and progress in anesthesiology in the second half of the 20th century, and to recognize the first half-century of the Journal's existence.

SOURCE

The content of the Journal from its inauguration in 1954 through 2004 was reviewed.

RESULTS

Although the data base is that of the Canadian Journal, many of the contributions were from other countries, and for this reason the findings will have relevance both in Canada and elsewhere. The review suggests that anesthesiology evolved in two phases in this period: from 1954 to 1978 and from 1979 to 2004. The first was characterized by the introduction of new drugs and adaptation to new surgical techniques; the second, by a greater emphasis on clinical excellence, outcome, quality patient care both in the operating room and elsewhere in the hospital, and research.

CONCLUSIONS

Although profound advances in knowledge, techniques, and relationships, have shaped the pattern and practice of anesthesiology in this half-century, the basic concerns of anesthesiologists relating to the practice of anesthesia and to their patients remained unchanged. At the same time, the many advances that have shaped anesthesiology in this half-century have extended the understanding of the phenomenon of anesthesia and enhanced the quality of patient care, which gives rise to the hope that anesthesiologists will continue to fully achieve these twin goals in the next half-century.