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Introduction: In paediatric rehabilitation at Grandview Kids in Oshawa, Ontario, Canada, integrated care begins at intake, with direct input from parents/caregivers, children and youth, to form the goals that will drive service provision. As practitioners continued to embed emerging best practices and policies to support seamless transfer between disciplines, families require additional support throughout their journeys. In 2012, Grandview Kids began the formation of a novel approach of a Family Engagement Team (FET) that is embedded into the development, implementation, and evaluation of daily practice. Aims, objectives, theory or methods: Building upon our NACI2021 presentation, this presentation will showcase the evolution of the Grandview FET to answer the question: “What are the actionable strategies for meaningful partnerships with patients and families?” The FET was founded on the principles that clients and families/caregivers are key partners in care and their voices must be embedded into programs, services, and decision-making processes. Strategies included: senior leadership support; investing in family leaders as employees or volunteers; shifting the focus from top-down to bottom-up engagement co-design with families; and embedding peer support referral process into models of care. Process evaluation outcomes will be shared. Highlights or results or key findings: The senior leaders with support from the Board of Directors recognized parents/caregivers were more than “service users” but partners in the development, implementation, and evaluation of programs and services. A Family Facilitator Role was established as a full-time employee who led the development of a Family Advisory Council, an Online Parent Support program, and a Youth Advisory Committee. In 2021, the FET has seven paid employees that are current or past parents of clients or were clients, themselves. This expanded FET serve the function of capacity building (e.g., staff training, caregiver workshops, peer support), advocacy and citizenship (e.g., partnering across organizations to voice the needs of families of children and youth with disabilities), and client and caregiver engagement (e.g., co-design of programs, contribution to accreditation). The FET has been successfully embedded into daily practice, with a formal referral process at any point of a client’s journey (e.g., intake, assessment, transitions). Conclusions: Parents/caregivers become true partners in care when they are embedded into the primary functions of the healthcare organization. At Grandview Kids, the FET has built trust among families and clinicians, bolstering a model of integrated care by establishing clear parameters to engage families as active participants in their child/youth’s journey.Implications for applicability/transferability, sustainability, and limitations: The Grandview Kids’ FET will share their lived experiences developing meaningful partnerships with families. To begin, the FET must have support from the senior leadership, be willing to reach out to families to collect feedback, and be willing to act on the outcomes; the positive and the challenging.

Background Transfusion of blood at the limits of approved storage time is associated with lower red blood cell (RBC) post-transfusion recovery and hemolysis, which increases plasma cell-free hemoglobin and iron, proposed to induce endothelial dysfunction and impair host defense. There is noted variability among donors in the intrinsic rate of storage changes and RBC post-transfusion recovery, yet genetic determinants that modulate this process are unclear. Methods We explore RBC storage stability and post-transfusion recovery in murine models of allogeneic and xenogeneic transfusion using blood from humanized transgenic sickle cell hemizygous mice (Hbatm1PazHbbtm1TowTg(HBA-HBBs)41Paz/J) and human donors with a common genetic mutation sickle cell trait (HbAS). Findings Human and transgenic HbAS RBCs demonstrate accelerated storage time-dependent hemolysis and reduced post-transfusion recovery in mice. The rapid post-transfusion clearance of stored HbAS RBC is unrelated to macrophage-mediated uptake or intravascular hemolysis, but by enhanced sequestration in the spleen, kidney and liver. HbAS RBCs are intrinsically different from HbAA RBCs, with reduced membrane deformability as cells age in cold storage, leading to accelerated clearance of transfused HbAS RBCs by entrapment in organ microcirculation. Interpretation The common genetic variant HbAS enhances RBC storage dysfunction and raises provocative questions about the use of HbAS RBCs at the limits of approved storage., Highlights • Sickle cell trait (HbAS) RBC exhibit increased resistance to osmotic shock compared to normal (HbAA) RBCs. • HbAS RBC show accelerated storage-related aging and post-transfusion clearance after cold storage compared to HbAA RBC. • Reduced post-transfusion survival of stored HbAS RBCs is not due to intravascular hemolysis but due to tissue sequestration. In allogeneic transfusions, red blood cells (RBCs) are collected and stored for up to 42 days. Historically, donor RBC genetic background is only considered in the context of major Rh and ABO blood groups. This study shows that donor-specific genetic factors such as sickle cell trait, the benign heterozygote state of sickle cell disease, accelerate storage-related hemolysis and reduces RBC post-transfusion survival in mice. Impaired post-transfusion recovery is due to enhanced sequestration in organ microcirculation. Further studies are warranted to determine an appropriate earlier outdate for HbAS RBC units, particularly in malaria-endemic regions where sickle cell trait prevalence is high.

BACKGROUND Sickle cell disease (SCD) is characterized by hemoglobin polymerization upon deoxygenation. Polymerization causes the sickle cells to become rigid and misshapen (sickling). Red blood cell (RBC) dehydration greatly increases polymerization. Cycles of sickling and unsickling cause an influx of calcium that leads to loss of potassium via the calcium-activated Gardos channel, which dehydrates the cells leading to increased polymerization. In this study the effects of nitric oxide (NO) and its congeners on RBC deformability were examined, focusing on sickle RBCs (sRBCs). STUDY DESIGN AND METHODS RBCs from patients with SCD and from nonpatients were exposed to various compounds that release NO or its congeners. Intracellular calcium was increased using a calcium ionophore or cycling of oxygen tension for sRBCs. Deformability was measured by laser-assisted osmotic gradient ektacytometry. RESULTS Consistent with a previous report, sodium nitroprusside (SNP) was found to protect against calcium-induced loss of deformability in normal RBCs, but (contrary to some previous reports) no effect of any NO donors was observed when calcium influx was not induced. Importantly, in studies of deoxygenation-induced dehydration of sRBCs, SNP resulted in substantial improvements in deformability (p = 0.036) and hydration (p = 0.024). Sodium nitrite showed similar trends. SNP was shown to have no effect on calcium influx, but reduced potassium efflux. CONCLUSION These data suggest that SNP and perhaps certain nitrogen oxides (like nitrite) inhibit the Gardos channel and may be able to protect sickle cells from dehydration and thereby improve outcome in the disease.

Nitrite signaling likely occurs through its reduction to nitric oxide (NO). Several reports support a role of erythrocytes and hemoglobin in nitrite reduction, but this remains controversial, and alternative reductive pathways have been proposed. In this work we determined whether the primary human erythrocytic nitrite reductase is hemoglobin as opposed to other erythrocytic proteins that have been suggested to be the major source of nitrite reduction. We employed several different assays to determine NO production from nitrite in erythrocytes including electron paramagnetic resonance detection of nitrosyl hemoglobin, chemiluminescent detection of NO, and inhibition of platelet activation and aggregation. Our studies show that NO is formed by red blood cells and inhibits platelet activation. Nitric oxide formation and signaling can be recapitulated with isolated deoxyhemoglobin. Importantly, there is limited NO production from erythrocytic xanthine oxidoreductase and nitric-oxide synthase. Under certain conditions we find dorzolamide (an inhibitor of carbonic anhydrase) results in diminished nitrite bioactivation, but the role of carbonic anhydrase is abrogated when physiological concentrations of CO2 are present. Importantly, carbon monoxide, which inhibits hemoglobin function as a nitrite reductase, abolishes nitrite bioactivation. Overall our data suggest that deoxyhemoglobin is the primary erythrocytic nitrite reductase operating under physiological conditions and accounts for nitrite-mediated NO signaling in blood.

Carbon monoxide (CO) is a leading cause of poisoning deaths worldwide, with no available antidotal therapy. We introduce a potential treatment paradigm for CO poisoning, based on near-irreversible binding of CO by an engineered human neuroglobin (Ngb). Ngb is a six-coordinate hemoprotein, with the heme iron coordinated by two histidine residues. We mutated the distal histidine to glutamine (H64Q) and substituted three surface cysteines with less reactive amino acids to form a five-coordinate heme protein (Ngb-H64Q-CCC). This molecule exhibited an unusually high affinity for gaseous ligands, with a P50 (partial pressure of O2 at which hemoglobin is half-saturated) value for oxygen of 0.015 mmHg. Ngb-H64Q-CCC bound CO about 500 times more strongly than did hemoglobin. Incubation of Ngb-H64Q-CCC with 100% CO-saturated hemoglobin, either cell-free or encapsulated in human red blood cells, reduced the half-life of carboxyhemoglobin to 0.11 and 0.41 min, respectively, from ≥200 min when the hemoglobin or red blood cells were exposed only to air. Infusion of Ngb-H64Q-CCC to CO-poisoned mice enhanced CO removal from red blood cells, restored heart rate and blood pressure, increased survival, and was followed by rapid renal elimination of CO-bound Ngb-H64Q-CCC. Heme-based scavenger molecules with very high CO binding affinity, such as our mutant five-coordinate Ngb, are potential antidotes for CO poisoning by virtue of their ability to bind and eliminate CO.

A major abnormality that characterizes the red cell "storage lesion" is increased hemolysis and reduced red cell lifespan after infusion. Low levels of intravascular hemolysis after transfusion of aged stored red cells disrupt nitric oxide (NO) bioavailabity, via accelerated NO scavenging reaction with cell-free plasma hemoglobin. The degree of intravascular hemolysis post-transfusion and effects on endothelial-dependent vasodilation responses to acetylcholine have not been fully characterized in humans.To evaluate the effects of blood aged to the limits of Food and Drug Administration-approved storage time on the human microcirculation and endothelial function.Eighteen healthy individuals donated 1 U of leukopheresed red cells, divided and autologously transfused into the forearm brachial artery 5 and 42 days after blood donation. Blood samples were obtained from stored blood bag supernatants and the antecubital vein of the infusion arm. Forearm blood flow measurements were performed using strain-gauge plethysmography during transfusion, followed by testing of endothelium-dependent blood flow with increasing doses of intraarterial acetylcholine.We demonstrate that aged stored blood has higher levels of arginase-1 and cell-free plasma hemoglobin. Compared with 5-day blood, the transfusion of 42-day packed red cells decreases acetylcholine-dependent forearm blood flows. Intravascular venous levels of arginase-1 and cell-free plasma hemoglobin increase immediately after red cell transfusion, with more significant increases observed after infusion of 42-day-old blood.We demonstrate that the transfusion of blood at the limits of Food and Drug Administration-approved storage has a significant effect on the forearm circulation and impairs endothelial function. Clinical trial registered with www.clinicaltrials.gov (NCT 01137656).

A method is presented for calibrating the wavelength assignments of a spectrometer. White light is launched through an unbalanced Michelson interferometer to produce an optical signal that varies strongly, but predictably, with wavelength. The spectrometer output is then compared to the predicted signal and the deviations found are assumed to be due to wavelength assignment errors, permitting the spectrometer to be calibrated. The details of this process are presented with an example.