Transfusion Considerations in Pediatric Hematology and Oncology Patients

Differences between capillary and venous blood counts in children-A data mining approach

BACKGROUND

Capillary sampling of blood counts is a well-established alternative to venipuncture in paediatrics. However, the sampling method has to be considered when interpreting test results, as measurements differ. Ethical and practical considerations prevent simultaneous venous and capillary sample acquisition in comprehensive paediatric cohorts that span all ages for the purpose of a direct method comparison, resulting in uncertainty regarding the interpretation of capillary test results.

METHODS

We applied a data mining method to calculate the differences between capillary and venous blood count analytes using laboratory data collected during patient care. We examined 486 401 blood counts performed between 2010 and 2017 in two German paediatric tertiary care centers in children from birth to 18 years analysed on SYSMEX XE-2100 and SYSMEX XE-5000 devices, and analysed the differences between capillary and venous test results in 15 218 paired samples performed within 24 h.

RESULTS

We identified the mean systematic differences between capillary and venous (capillary-venous) test results for haemoglobin (+6.5 g/L), haematocrit (+2.38%), platelet count (-7.01 × 10⁹ /l), red cell count (+0.18 × 10¹² /L), white cell count (-0.64 × 10⁹ /L), mean corpuscular cell volume (+2.07 fl), mean corpuscular haemoglobin (+0.33 pg), mean corpuscular haemoglobin concentration (-4.4 g/L) and red cell distribution width (+0.40%). The effect of age on these mean deltas is negligible, while the levels of test results influence the difference between capillary and venous test results in most analytes.

CONCLUSIONS

Our results improve guidance regarding the interpretation of capillary test results for children of all ages and in both physiological and pathological ranges.

Transfusion practices for pediatric oncology and hematopoietic stem cell transplantation patients: Data from the National Heart Lung and Blood Institute Recipient Epidemiology and Donor Evaluation Study-III (REDS-III)

BACKGROUND

To evaluate transfusion practices in pediatric oncology and hematopoietic stem cell transplant (HSCT) patients.

STUDY DESIGN AND METHODS

This is a multicenter retrospective study of children with oncologic diagnoses treated from 2013 to 2016 at hospitals participating in the National Heart Lung and Blood Institute Recipient Epidemiology and Donor Evaluation Study-III. Transfusion practices were evaluated by diagnosis codes and pre-transfusion laboratory values.

RESULTS

A total of 4766 inpatient encounters of oncology and HSCT patients were evaluated, with 39.3% (95% confidence interval [CI]: 37.9%-40.7%) involving a transfusion. Red blood cells (RBCs) were the most commonly transfused component (32.4%; 95% CI: 31.1%-33.8%), followed by platelets (22.7%; 95% CI: 21.5%-23.9%). Patients in the 1 to <6 years of range were most likely to be transfused and HSCT, acute myeloid leukemia, and aplastic anemia were the diagnoses most often associated with transfusion. The median hemoglobin (Hb) prior to RBC transfusion was 7.5 g/dl (10-90th percentile: 6.4-8.8 g/dl), with 45.7% of transfusions being given at 7 to <8 g/dl. The median platelet count prior to platelet transfusion was 20 × 10⁹ /L (10-90th percentile: 8-51 × 10⁹ /L), and 37.9% of transfusions were given at platelet count of >20-50 × 10⁹ /L. The median international normalized ratio (INR) prior to plasma transfusion was 1.7 (10-90th percentile: 1.3-2.7), and 36.3% of plasma transfusions were given at an INR between 1.4 and 1.7.

DISCUSSION

Transfusion of blood components is common in hospitalized pediatric oncology/HSCT patients. Relatively high pre-transfusion Hb and platelet values and relatively low INR values prior to transfusion across the studied diagnoses highlight the need for additional studies in this population.

The Relevance of Fluid and Blood Management Using Microcirculatory Parameters in Children Undergoing Craniofacial Surgery

ABSTRACT

Perioperative management of bleeding in children can be challenging. Microvascular imaging techniques have allowed evaluating the effect of blood transfusion on the microcirculation, but little is known about these effects in children. We aimed to investigate the effects of blood management using macro- and micro-hemodynamic parameters measurement in children undergoing craniofacial surgery. This is a prospective observational repeated measurement study including fourteen children. The indications for blood transfusion were changes of hemoglobin/hematocrit (Hct) levels, the presence of signs of altered tissue perfusion and impaired microcirculation images. Total and perfused vessel densities, proportion of perfused vessels, microvascular flow index, and systemic parameters (hemoglobin, Hct, lactate, mixed venous oxygen saturation, K+, heart rate, mean arterial blood pressure) were evaluated baseline (T1), at the end of the surgical bleeding (T2) and end of the operation (T3). Four patients did not need a blood transfusion. In the other 10 patients who received a blood transfusion, capillary perfusion was higher at T3 (13[9-16]) when compared with the values of at T2 (11[8-12]) (P < 0.05) but only 6 patients reached their baseline values. Although blood transfusions increased Hct values (17 ± 2.4 [T2]-19 ± 2.8 [T3]) (P < 0.05), there was no correlation between microvascular changes and systemic hemodynamic parameters (P > 0.05). The sublingual microcirculation could change by blood transfusion but there was not any correlation between microcirculation changes, hemodynamic, and tissue perfusion parameters even with Hct values. The indication, guidance, and timing of fluid and blood therapy may be assessed by bedside microvascular analysis in combination with standard hemodynamic and biochemical monitoring for intraoperative bleeding in children.

Transfusion outcome for volume- and plasma-reduced platelet concentrates for pediatric patients

BACKGROUND AND OBJECTIVES

Plasma reduction in platelet concentrate (PC) products has been reported to prevent large volume load and transfusion-related adverse reactions (TRARs). However, volume reduction might be associated with a poor transfusion response because of a deterioration in platelet (PLT) quality. Because PLT quality control and transfusion responses for recently washed PCs using PLT additive solutions are superior, we investigated the clinical safety and transfusion efficacy of volume-reduced washed PCs in pediatric patients.

MATERIALS AND METHODS

We prepared a simplified resuspended PC product (RPC) as a washed PC. Regular RPC (R-RPC) included equivalent volumes of bicarbonate Ringer's solution and anticoagulant citrate dextrose solution A (BRS-A) as the resuspension solution. Half RPC (H-RPC) was prepared by adding a half volume of BRS-A. Twenty-four pediatric patients were scheduled for transfusions with R-RPC and H-RPC up to 4 times. R-RPC was transfused 42 times into 24 patients. H-RPC was transfused 41 times into 23 patients.

RESULTS

Neither product was observed to cause TRARs. Although the calculated PLT recovery for H-RPC was significantly reduced, the posttransfusion corrected count increment (24 h) did not differ. Moreover, similar results were observed for vital signs during transfusion.

CONCLUSION

Volume-reduced washed PC can be transfused without causing TRARs, differences in vital signs, or inferior transfusion responses. Volume-reduced washed PC also provides the advantages of shortened transfusion times and reduced volume loads. Although a standard technique for stable resuspension is necessary, volume-reduced washed PC may be a beneficial option for children, including neonates, or individuals with cardiovascular or renal problems.

Society for the advancement of blood management administrative and clinical standards for patient blood management programs. 4th edition (pediatric version)

Patient Blood Management is the timely application of evidence-based medical and surgical concepts designed to maintain hemoglobin concentration, optimize hemostasis, and minimize blood loss to improve patient outcomes. Conceptually similar to a "bundle" strategy, it is designed to improve clinical care using comprehensive evidence-based treatment strategies to manage patients with potential or ongoing critical bleeding, bleeding diathesis, critical anemia, and/ or a coagulopathy. Patient Blood Management includes multimodal strategies to screen, diagnose and properly treat anemia, coagulopathies and minimize bleeding, using goal-directed therapy and leverages a patient's physiologic ability to adapt to anemia while definitive treatment is undertaken. Allogeneic blood component transfusion is one traditional therapeutic modality out of many for managing blood loss and anemia and, while it may be the best choice in certain situations, other effective and more appropriate options are available and should be used in conjunction or alone. Therefore, comprehensive Patient Blood Management is the new standard of care to prevent and manage anemia and optimize hemostasis and has been recommended by the World Health Organization, the American Society of Anesthesiologists, the European Society of Anaesthesiology and the Australian National Blood Authority. While there is a plethora of expert consensus and good practice guidelines published for blood component transfusion from multiple professional organizations and societies, there remains a need for more comprehensive and broader standards of patient medical management to proactively reduce the risk of exposure to allogeneic transfusions. In 2010, the Society for Advancement of Blood Management published the first comprehensive standards to address the administrative and clinical components of an effective, patient-centered Patient Blood Management program. Recognizing the need to reduce inappropriate transfusions, some professional organizations have placed their emphasis on transfusion guidelines. In contrast, the focus of the Society for Advancement of Blood Management Standard is on the centrality of the patient and the full spectrum of therapeutic strategies needed to improve clinical outcomes in patients at risk for blood loss or anemia, thereby reducing avoidable transfusions as well. The Standards are meant not to replace, but to complement transfusion guidelines by more completely addressing the need for a multi-modal clinical approach with the goal to improve patient outcomes. Compared to adult programs, Pediatric Patient Blood Management programs are currently not commonly accepted as standard of care for pediatric patients. This is partly due to the fact that, until recently, there was a paucity of robust evidence-based literature and expert consensus guidelines on pediatric PBM. Managing pediatric bleeding and blood product transfusion presents a unique set of challenges. The main goal of transfusion is to correct or avoid imminent inadequate oxygen carrying capacity caused by inadequate red blood cell mass. Determining when, what, and how much to transfuse can be difficult. Neonates, infants, children, and adolescents each have specific considerations based on age, weight, physiology, and pharmacology. In this edition of Pediatric Anaesthesia we provide, in abbreviated format, the 4th edition of the Administrative and Clinical Standards for Patient Blood Management; Pediatric Version, first published in 2010 with the addition of a new Pediatric section in 2016. These Standards provide guidance for implementing a comprehensive Pediatric Patient Blood Management program at both pediatric and adult medical institutions. While every hospital may not be equipped to have a dedicated Pediatric Patient Blood Management program, this document highlights important universal clinical strategies that can be implemented to optimize pediatric bleeding management and minimize allogeneic blood product exposure through the use of multi-modal therapeutic strategies that have their central emphasis on the patient rather than the transfusion. Important strategies include: treatment of preoperative anemia, standardized transfusion algorithms, the use of restrictive transfusion thresholds, goal-directed therapy based on point of care and viscoelastic testing, antifibrinolytics, and avoidance of hemodilution and hypothermia as supported by evidence. For the full version, please go to https://www.sabm.org/publications.