Interventions to prevent iatrogenic anemia: a Laboratory Medicine Best Practices systematic review.

BACKGROUND: As many as 90% of patients develop anemia by their third day in an intensive care unit (ICU). We evaluated the efficacy of interventions to reduce phlebotomy-related blood loss on the volume of blood lost, hemoglobin levels, transfusions, and incidence of anemia. METHODS: We conducted a systematic review and meta-analysis using the Laboratory Medicine Best Practices (LMBP) systematic review methods for rating study quality and assessing the body of evidence. Searches of PubMed, Embase, Cochrane, Web of Science, PsychINFO, and CINAHL identified 2564 published references. We included studies of the impact of interventions to reduce phlebotomy-related blood loss on blood loss, hemoglobin levels, transfusions, or anemia among hospital inpatients. We excluded studies not published in English and studies that did not have a comparison group, did not report an outcome of interest, or were rated as poor quality. Twenty-one studies met these criteria. We conducted a meta-analysis if > 2 homogenous studies reported sufficient information for analysis. RESULTS: We found moderate, consistent evidence that devices that return blood from flushing venous or arterial lines to the patient reduced blood loss by approximately 25% in both neonatal ICU (NICU) and adult ICU patients [pooled estimate in adults, 24.7 (95% CI = 12.1-37.3)]. Bundled interventions that included blood conservation devices appeared to reduce blood loss by at least 25% (suggestive evidence). The evidence was insufficient to determine if these devices reduced hemoglobin decline or risk of anemia. The evidence suggested that small volume tubes reduced the risk of anemia, but was insufficient to determine if they affected the volume of blood loss or the rate of hemoglobin decline. CONCLUSIONS: Moderate, consistent evidence indicated that devices that return blood from testing or flushing lines to the patient reduce the volume of blood loss by approximately 25% among ICU patients. The results of this systematic review support the use of blood conservation systems with arterial or venous catheters to eliminate blood waste when drawing blood for testing. The evidence was insufficient to conclude the devices impacted hemoglobin levels or transfusion rates. The use of small volume tubes may reduce the risk of anemia.

Shape-Changing Materials Using Variable Stiffness and Distributed Control.

We describe a robotic material that tightly integrates sensing, actuation, computation, and communication to perform autonomous shape change. The composite consists of multiple cells, each with the ability to control their local stiffness (by Joule heating of a thermoplastic) and communicate with their local neighbors. We also present a distributed algorithm for calculating the inverse kinematic solution of the resulting N-body system by iteratively solving a series of problems with reduced kinematics. We describe material design choices, mechanism design, algorithm, and manufacturing, emphasizing the interdisciplinary codesign problem that robotic materials pose, and demonstrate the results from a series of shape-changing experiments.

Use of an electronic decision support tool improves management of simulated in-hospital cardiac arrest.

INTRODUCTION: Adherence to advanced cardiac life support (ACLS) guidelines during in-hospital cardiac arrest (IHCA) is associated with improved outcomes, but current evidence shows that sub-optimal care is common. Successful execution of such protocols during IHCA requires rapid patient assessment and the performance of a number of ordered, time-sensitive interventions. Accordingly, we sought to determine whether the use of an electronic decision support tool (DST) improves performance during high-fidelity simulations of IHCA. METHODS: After IRB approval and written informed consent was obtained, 47 senior medical students were enrolled. All participants were ACLS certified and within one month of graduation. Each participant was issued an iPod Touch device with a DST installed that contained all ACLS management algorithms. Participants managed two scenarios of IHCA and were allowed to use the DST in one scenario and prohibited from using it in the other. All participants managed the same scenarios. Simulation sessions were video recorded and graded by trained raters according to previously validated checklists. RESULTS: Performance of correct protocol steps was significantly greater with the DST than without (84.7% v 73.8%, p<0.001) and participants committed significantly fewer additional errors when using the DST (2.5 errors vs. 3.8 errors, p<0.012). CONCLUSION: Use of an electronic DST provided a significant improvement in the management of simulated IHCA by senior medical students as measured by adherence to published guidelines.

Anemia, bleeding, and blood transfusion in the intensive care unit: causes, risks, costs, and new strategies.

The definition of anemia is controversial and varies with the sex, age, and ethnicity of the patient. Anemia afflicts half of hospitalized patients and most elderly hospitalized patients. Acute anemia in the operating room or intensive care unit is associated with increased morbidity as well as other adverse outcomes, including death. The risks of anemia are compounded by the added risks associated with transfusion of red blood cells, the most common treatment for severe anemia. The causes of anemia in hospitalized patients include iron deficiency, suppression of erythropoietin and iron transport, trauma, phlebotomy, coagulopathies, adverse effects of and reactions to medications, and stress-induced gastrointestinal bleeding. The types and causes of anemia and the increased health care utilization and costs associated with anemia and undetected internal bleeding are described. The potential benefits and risks associated with transfusion of red blood cells also are explored. Last, the strategies and new tools to help prevent anemia, allow earlier detection of internal bleeding, and avoid unnecessary blood transfusions are discussed.

CPEB1 regulates beta-catenin mRNA translation and cell migration in astrocytes.

A crucial step in directed cell migration is the recruitment of cytoskeletal regulatory and signaling proteins to the leading edge of the cell. One protein localized to the leading edge of a migrating astrocyte is beta-catenin. Using an in vitro wound-healing assay, we show that the localization of beta-catenin to the leading edge is dependent upon new protein synthesis at the time of wounding. We examined the mRNA encoding beta-catenin for potential regulatory elements and identified a conserved cytoplasmic polyadenylation element in the 3'-untranslated region (UTR). We now show that the CPE-binding protein (CPEB1) is expressed in astrocytes and that translation of beta-catenin mRNA is regulated by CPEB1. Further, expression of a mutant CPEB1 protein in astrocytes not only blocks beta-catenin protein localization, it also inhibits cell migration. These findings demonstrate a role for CPEB1-mediated protein synthesis in the localization of beta-catenin protein to the leading edge of migrating astrocytes and in regulating directed cell motility.

Cytoplasmic polyadenylation element binding protein 1-mediated mRNA translation in Purkinje neurons is required for cerebellar long-term depression and motor coordination.

The ability of neurons to modify synaptic connections is critical for proper brain development and function in the adult. It is now clear that changes in synaptic strength are often accompanied by changes in synaptic morphology. This synaptic plasticity can be maintained for varying lengths of time depending on the type of neuronal activity that first induced the changes. Long-term synaptic plasticity requires the synthesis of new proteins, and one mechanism for the regulation of experience-induced protein synthesis in neurons involves cytoplasmic polyadenylation element binding protein (CPEB1). CPEB1 can bidirectionally regulate mRNA translation, first repressing translation, and then activating translation after the phosphorylation of two critical residues (T171 and S177). To determine the full extent of CPEB1-mediated protein synthesis in synaptic function, we engineered a line of mice expressing CPEB1 with these phosphorylation sites mutated to alanines (mCPEB1-AA) exclusively in cerebellar Purkinje neurons (PNs). Thus, mRNAs bound by mCPEB1-AA would be held in a translationally dormant state. We show that mCPEB1-AA localizes to synapses in cerebellum and resulted in a loss of protein synthesis-dependent phase of parallel fiber-PN long-term depression. This was accompanied by a change in spine number and spine length that are likely attributable in part to the dysregulation of IRSp53, a protein known to play a role in synaptic structure. Finally, mCPEB1-AA mice displayed a significant impairment of motor coordination and a motor learning delay.