Patient blood management, what does this actually mean for neonates and infants?

Is noninvasive hemoglobin measurement suitable for children undergoing preoperative anesthesia consultation?

Preoperative anemia in children is a significant clinical concern requiring precise diagnosis. Although traditional blood sample collection is effective, it poses challenges because of children's aversion and technical difficulties. Therefore, this study explores the suitability of noninvasive hemoglobin measurements in children during preoperative anesthesia consultation. Noninvasive hemoglobin measurement (SpHb®; Masimo) in children aged ≤ 17 years was performed during preoperative anesthesia consultation and compared with laboratory hemoglobin (labHb) levels. SpHb was measured in 62 children (median age: 6 years, standard deviation [SD] ± 5.3) without adverse effects but was unsuccessful in one child. The bias, limits of agreement, and root mean square error between SpHb and labHb were 0.3, -2.26- +2.8, and 1.3 g/dl, respectively. LabHb demonstrated a significant regression relationship with R2 of 0.359. LabHb was associated with a negative effect on bias [- 0.443 (CI 95: - 0.591- - 0.153, P < 0.001)], i.e., SpHb tends to underestimate labHb for high labHb values. The retest reliability between two consecutive SpHb measurements was 0.727 (P < 0.001). Double measurement of SpHb, age, weight, sex, heart rate, and perfusion index had no significant effects on accuracy. Using SpHb, a specificity of 96.3% (95% confidence interval [CI 95]: 87.3%-99.5%) and a sensitivity of 57.1% (CI 95: 18.4%-90.1%) were observed. Based on adapted cut-off values for SpHb (age-dependent cut-off values plus 0.8 g/dl), a sensitivity of 100% (CI 95: 64.6%-100%) was achieved for the investigated study collective. SpHb measurement in children is a quick procedure. The accuracy of hemoglobin measurement is insufficient for the diagnosis of anemia. Thus, whether the calculated cut-off SpHb values of this study collective can be considered for anemia screening in pediatric patients undergoing preoperative anesthesia consultation should be confirmed. Trial registration number and date of registration: This prospective study was registered at ClinicalTrials.gov (NCT03586141).

Patient Blood Management in Neonates

Patient blood management (PBM) is an evidence-based care package to improve patient outcomes by optimizing a patient's blood, minimizing blood loss, and the effective management and, when appropriate, the tolerance of anemia. It is relatively well-developed in adult medicine and remains in its infancy in neonatology. This review explores why evidence-based guidelines are insufficient, discusses the variations in neonatal transfusion practice and why this matters, and provides the key updates in neonatal transfusion practice. The authors give examples of a successful neonatal PBM program and single-center projects.

Patient blood management in critically ill children undergoing cardiac surgery: A cohort study

OBJECTIVE

The objective of this study was to audit current patient blood management practice in children throughout cardiac surgery and paediatric intensive care unit (PICU) admission.

DESIGN

This was a prospective observational cohort study.

SETTING

This was a single-centre study in the cardiac operating room (OR) and PICU in a major tertiary children's hospital in Australia.

PATIENTS

Children undergoing corrective cardiac surgery and requiring admission to PICU for postoperative recovery were included in the study.

MEASUREMENTS AND MAIN RESULTS

Fifty-six patients and 1779 blood sampling episodes were audited over a 7-month period. The median age was 9 months (interquartile range [IQR] = 1-102), with the majority (n = 30 [54%]) younger than 12 months. The median number of blood sampling episodes per patient per day was 6.6 (IQR = 5.8-8.0) in total, with a median of 5.0 (IQR = 4.0-7.5) episodes in the OR and 5.0 (IQR = 3.4-6.2) episodes per day throughout PICU admission. The most common reason for blood tests across both OR and PICU settings was arterial blood gas analysis (total median = 86%, IQR = 79-96). The overall median blood sampling volume per kg of bodyweight, patient, and day was 0.63 mL (IQR = 0.20-1.14) in total. Median blood loss for each patient was 3.5 mL/kg per patient per day (IQR = 1.7-5.6) with negligible amounts in the OR and a median of 3.6 mL/kg (IQR = 1.7-5.7) in the PICU. The median Cell Saver® transfusion volume was 9.9 mL/kg per patient per day (IQR = 4.0-19.1) in the OR. The overall median volume of other infusion products (albumin 4%, albumin 20%, packed red blood cells) received by each patient was 20.1 mL/kg (IQR = 10.7-36.4) per day. Sampling events and blood loss were positively associated with PICU stay.

CONCLUSIONS

Patient blood management practices observed in this study largely conform to National Blood Authority guidelines. Further implementation projects and research are needed to accelerate implementation of known effective blood conservation strategies within paediatric critical care environments.

Patients' Choice, Consent, and Ethics in Patient Blood Management

The goal of patient blood management (PBM) is to optimize clinical outcomes for individual patients by managing their blood as a precious and unique resource to be safeguarded and managed judiciously. A corollary to successful PBM is the minimization or avoidance of blood transfusion and stewardship of donated blood. The first is achieved by a multidisciplinary approach with personalized management plans shared and decided on with the patient or their substitute. It follows that the physician-patient relationship is an integral component of medical practice and the fundamental link between patient and doctor based on trust and honest communication. Central to PBM is accurate and timely diagnosis based on sound physiology and pathophysiology as the bedrock on which scientifically based medicine is founded. PBM in all disease contexts starts with the questions, "What is the status of the patient's blood?" "If there are specific abnormalities in the blood, how should they be managed?" and "If allogeneic blood transfusion is considered, is there no reasonable alternative therapy?" There are compelling scientific reasons to implement a nontransfusion default position when there is clinical uncertainty and questionable evidence of clinical efficacy for allogeneic blood transfusion due to known potential hazards. Patients must be informed of their diagnosis, the nature, severity and prognosis of the disease, and treatment options along with risks and benefits. They should be involved in decision-making regarding their management. However, as part of this process, there are multifaceted medical, legal, ethical, and economic issues, encompassing shared decision-making, patient choice, and informed consent. Furthermore, variability in patient circumstances and preferences, the complexity of medical science, and the workings of health care systems in which consent takes place can be bewildering, not only for the patient but also for clinicians obtaining consent. Adding "patient" to the concept of blood management differentiates it from "donor" blood management to avoid confusion and the perception that PBM is a specific medical intervention. Personalized PBM is tailoring the PBM to the specific characteristics of each patient. With this approach, there should be no difficulty addressing the informed consent and ethical aspects of PBM. Patients can usually be reassured that there is nothing out of order with their blood, in which case the focus of PBM is to keep it that way. In some circumstances, a hematologist may be involved as a patient's blood advocate when abnormalities require expert involvement while the primary disease is being managed.

Iatrogenic Blood Loss in Very Low Birth Weight Infants and Transfusion of Packed Red Blood Cells in a Tertiary Care Neonatal Intensive Care Unit

An adequate blood volume is important for neonatal adaptation. The study objective was to quantify the cumulative iatrogenic blood loss in very low birth weight (VLBW) infants by blood sampling and the necessity of packed red cell transfusions from birth to discharge from the hospital. In total, 132 consecutive VLBW infants were treated in 2019 and 2020 with a median birth weight of 1180 g (range 370–1495 g) and a median length of stay of 54 days (range 0–154 days) were included. During the initial four weeks of life, the median absolute amount of blood sampling was 16.5 mL (IQR 12.3–21.1 mL), sampling volume was different with 14.0 mL (IQR 12.1–16.2 mL) for non-transfused infants and 21.6 mL (IQR 17.5–29.4 mL) for transfused infants. During the entire length of stay, 31.8% of the patients had at least one transfusion. In a generalized logistic regression model, the cumulative amount of blood sampling (p < 0.01) and lower hematocrit at birth (p = 0.02) were independent predictors for the necessity of blood transfusion. Therefore, optimized patient blood management in VLBW neonates should include sparse blood sampling to avoid iatrogenic blood loss.

Establishing reference ranges of cord blood: point-of-care hemostatic function assessment in preterm and term neonates

BACKGROUND

Thrombelastometry, allowing timely assessment of global hemostatic function, is increasingly used to guide hemostatic interventions in bleeding patients. Reference values are available for adults and children, including infants but not neonates immediately after birth.

METHODS

Neonates were grouped as preterm (30 + 0 to 36 + 6 weeks/days) and term (37 + 0 to 39 + 6 weeks/days). Blood samples were drawn from the umbilical cord immediately after cesarean section and analyzed by thrombelastometry. Reference ranges were determined for the extrinsic and intrinsic coagulation pathways, fibrin polymerization, and hyperfibrinolysis detection.

RESULTS

All extrinsically activated test parameters, but maximum lysis (P = 0.139) differed significantly between both groups (P ≤ 0.001). Maximum clot firmness in the fibrin polymerization test was comparable (P = 0.141). All intrinsically activated test parameters other than coagulation time (P = 0.537) and maximum lysis (P = 0.888) differed significantly (P < 0.001), and so did all aprotinin-related test parameters (P ≤ 0.001) but maximum lysis (P = 0.851).

CONCLUSIONS

This is the first study to identify reference ranges for thrombelastometry in preterm and term neonates immediately after birth. We also report differences in clot initiation and clot strength in neonates born <37 versus ≤40 weeks of gestation, mirroring developmental hemostasis.

IMPACT

Impact: This prospective observational study is the first to present reference ranges in preterm and term infants for all types of commercially available tests of thrombelastometry, notably also including the fibrin polymerization test.

IMPORTANCE

Viscoelastic coagulation assays such as thrombelastometry have become integral to the management of perioperative bleeding by present-day standards. Reference values are available for adults, children, and infants but not for neonates. Key message: Clot initiation and formation was faster and clot strength higher in the term than in the preterm group. Parameters of thrombelastometry obtained from cord blood do not apply interchangeably to preterm and term neonates.

Closing the evidence to practice gap in neonatal transfusion medicine

Significant resources are directed towards world-class research projects, but the findings are not necessarily translated into better healthcare outcomes, either at all or in a sustained way. There is a clear need to dedicate further resources to understanding how to promote the uptake of evidence and effectively change neonatal transfusion practice to improve outcomes. Approaching blood transfusion behaviour change more systematically, and working across disciplines and involving families, holds the potential to increase the rate of uptake of emerging evidence in clinical practice. This approach holds the potential to save costs, conserve resources, and improve clinical outcomes. Our paper focuses on the use of quality improvement to bridge the gap between evidence-based knowledge and transfusion practice in neonatal units around the world.

Neonatal red blood cell transfusion

Transfusions are more common in premature infants with approximately 40% of low birth weight infants and up to 90% of extremely low birth weight infants requiring red blood cell transfusion. Although red blood cell transfusion can be life-saving in these preterm infants, it has been associated with higher rates of complications including necrotizing enterocolitis, bronchopulmonary dysplasia, retinopathy of prematurity and possibly abnormal neurodevelopment. The main objective of this review is to assess current red blood cell transfusion practices in the neonatal intensive care unit, to summarize available neonatal transfusion guidelines published in different countries and to emphasize the wide variation in transfusion thresholds that exists for red blood cell transfusion. This review also addresses certain issues specific to red blood cell processing for the neonatal population including storage time, irradiation, cytomegalovirus (CMV) prevention strategies and patient blood management. Future research avenues are proposed to better define optimal transfusion practice in neonatal intensive care units.

Embedding best transfusion practice and blood management in neonatal intensive care

Background

Transfusion is a common procedure for neonates receiving intensive care management. Recognising a paucity of patient blood management (PBM) programmes in neonates, we aimed to embed blood management and best transfusion principles in the neonatal intensive care unit (NICU) by aligning local policies, providing targeted education and partnering with parents.

Methods

Practice-based evidence for clinical practice improvement (PBE-CPI) methodology was used. Previous hospital accreditation audits were reviewed and a neonate-specific transfusion audit was developed. Audit was performed at baseline and repeated following the intervention period. NICU clinicians received targeted education in obtaining informed consent, prescription and safe administration of blood components during a ‘Blood Month’ awareness period. A neonate-specific parent handout about transfusion was developed in partnership with parents. A pilot video demonstrating a shared consent discussion was also developed to assist in the consent process. Parents’ knowledge, concerns and feedback regarding transfusion practice was sought at baseline (survey) and on project completion (experience trackers).

Results

Neonate-specific baseline transfusion audit showed inconsistent consent, monitoring and documentation processes in neonatal transfusions. Post-targeted education audit showed improvement in these parameters. The targeted PBM and transfusion-related education delivered during ‘Blood Month’ was well-received by staff. Parents’ feedback about the NICU transfusion consenting process was consistently positive. NICU medical and nursing clinicians (n=25) surveyed agreed that the parent handout was well set out, easy to understand and recommended that it be used to complement practice.

Conclusion

PBE-CPI tools aligned with Australian PBM guidelines for clinicians and parents were well-accepted by clinical stakeholders and were associated with practice improvement in PBM awareness and transfusion consent processes. This PBE-CPI project developed NICU-specific consent information, not previously available, by partnering with parents to ensure quality of care in transfusion practice. Adoption of this also helps to meet accreditation for Australian Blood Management Standards. These strategies and tools translate readily into other NICUs to embed and support best PBM and transfusion practice.

Quantification of total haemoglobin concentrations in human whole blood by spectroscopic visible-light optical coherence tomography

The non-invasive quantification of total haemoglobin concentrations [tHb] is highly desired for the assessment of haematologic disorders in vulnerable patient groups, but invasive blood sampling is still the gold standard in current clinical practice. This work demonstrates the potential of visible-light spectroscopic optical coherence tomography (sOCT) for quantifying the [tHb] in human whole blood. To accurately quantify the [tHb] from the substantial optical attenuation by blood in the visible wavelength range, we used a combination of zero-delay acquisition and focus tracking that ensures optimal system sensitivity at any depth inside the sample. Subsequently, we developed an analysis model to adequately correct for the high scattering contribution by red blood cells to the sOCT signal. We validate our method and compare it to conventional sOCT (without focus tracking and zero-delay acquisition) through ex-vivo measurements on flowing human whole blood, with [tHb] values in the clinical range of 7-23 g/dL. For our method with optimized sensitivity, the measured and expected values correlate well (Pearson correlation coefficient = 0.89, p < 0.01), with a precision of 3.8 g/dL. This is a considerable improvement compared to conventional sOCT (Pearson correlation coefficient = 0.59, p = 0.16; precision of 9.1 g/dL).

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.