The Long-term Value of Bariatric Surgery Interventions for American Adults With Type 2 Diabetes Mellitus.

BACKGROUND: Bariatric surgery can cause type 2 diabetes (diabetes) remission for individuals with comorbid obesity, yet utilization is <1%. Surgery eligibility is currently limited to body mass index (BMI) ≥35 kg/m 2 , though the American Diabetes Association recommends expansion to BMI ≥30 kg/m 2 . OBJECTIVE: We estimate the individual-level net social value benefits of diabetes remission through bariatric surgery and compare the population-level effects of expanding eligibility alone versus improving utilization for currently eligible individuals. METHODS: Using microsimulation, we quantified the net social value (difference in lifetime health/economic benefits and costs) of bariatric surgery-related diabetes remission for Americans with obesity and diabetes. We compared projected lifetime surgical outcomes to conventional management at individual and population levels for current utilization (1%) and eligibility (BMI ≥35 kg/m 2 ) and expansions of both (>1%, and BMI ≥30 kg/m 2 ). RESULTS: The per capita net social value of bariatric surgery-related diabetes remission was $264,670 (95% confidence interval: $234,527-294,814) under current and $227,114 (95% confidence interval: $205,300-248,928) under expanded eligibility, an 11.1% and 9.16% improvement over conventional management. Quality-adjusted life expectancy represented the largest gains (current: $194,706; expanded: $169,002); followed by earnings ($51,395 and $46,466), and medical savings ($41,769 and $34,866) balanced against the surgery cost ($23,200). Doubling surgical utilization for currently eligible patients provides higher population gains ($34.9B) than only expanding eligibility at current utilization ($29.0B). CONCLUSIONS: Diabetes remission following bariatric surgery improves healthy life expectancy and provides net social benefit despite high procedural costs. Per capita benefits appear greater among currently eligible individuals. Therefore, policies that increase utilization may produce larger societal value than expanding eligibility criteria alone.

Economic benefits of microprocessor controlled prosthetic knees: a modeling study.

BACKGROUND: Advanced prosthetic knees allow for more dynamic movements and improved quality of life, but payers have recently started questioning their value. To answer this question, the differential clinical outcomes and cost of microprocessor-controlled knees (MPK) compared to non-microprocessor controlled knees (NMPK) were assessed. METHODS: We conducted a literature review of the clinical and economic impacts of prosthetic knees, convened technical expert panel meetings, and implemented a simulation model over a 10-year time period for unilateral transfemoral Medicare amputees with a Medicare Functional Classification Level of 3 and 4 using estimates from the published literature and expert input. The results are summarized as an incremental cost effectiveness ratio (ICER) from a societal perspective, i.e., the incremental cost of MPK compared to NMPK for each quality-adjusted life-year gained. All costs were adjusted to 2016 U.S. dollars and discounted using a 3% rate to the present time. RESULTS: The results demonstrated that compared to NMPK over a 10-year time period: for every 100 persons, MPK results in 82 fewer major injurious falls, 62 fewer minor injurious falls, 16 fewer incidences of osteoarthritis, and 11 lives saved; on a per person per year basis, MPK reduces direct healthcare cost by $3676 and indirect cost by $909, but increases device acquisition and repair cost by $6287 and total cost by $1702; on a per person basis, MPK is associated with an incremental total cost of $10,604 and increases the number of life years by 0.11 and quality adjusted life years by 0.91. MPK has an ICER ratio of $11,606 per quality adjusted life year, and the economic benefits of MPK are robust in various sensitivity analyses. CONCLUSIONS: Advanced prosthetics for transfemoral amputees, specifically MPKs, are associated with improved clinical benefits compared to non-MPKs. The economic benefits of MPKs are similar to or even greater than those of other medical technologies currently reimbursed by U.S. payers.

Geometric control of vascular networks to enhance engineered tissue integration and function.

Tissue vascularization and integration with host circulation remains a key barrier to the translation of engineered tissues into clinically relevant therapies. Here, we used a microtissue molding approach to demonstrate that constructs containing highly aligned "cords" of endothelial cells triggered the formation of new capillaries along the length of the patterned cords. These vessels became perfused with host blood as early as 3 d post implantation and became progressively more mature through 28 d. Immunohistochemical analysis showed that the neovessels were composed of human and mouse endothelial cells and exhibited a mature phenotype, as indicated by the presence of alpha-smooth muscle actin-positive pericytes. Implantation of cords with a prescribed geometry demonstrated that they provided a template that defined the neovascular architecture in vivo. To explore the utility of this geometric control, we implanted primary rat and human hepatocyte constructs containing randomly organized endothelial networks vs. ordered cords. We found substantially enhanced hepatic survival and function in the constructs containing ordered cords following transplantation in mice. These findings demonstrate the importance of multicellular architecture in tissue integration and function, and our approach provides a unique strategy to engineer vascular architecture.

Rapid casting of patterned vascular networks for perfusable engineered three-dimensional tissues.

In the absence of perfusable vascular networks, three-dimensional (3D) engineered tissues densely populated with cells quickly develop a necrotic core. Yet the lack of a general approach to rapidly construct such networks remains a major challenge for 3D tissue culture. Here, we printed rigid 3D filament networks of carbohydrate glass, and used them as a cytocompatible sacrificial template in engineered tissues containing living cells to generate cylindrical networks that could be lined with endothelial cells and perfused with blood under high-pressure pulsatile flow. Because this simple vascular casting approach allows independent control of network geometry, endothelialization and extravascular tissue, it is compatible with a wide variety of cell types, synthetic and natural extracellular matrices, and crosslinking strategies. We also demonstrated that the perfused vascular channels sustained the metabolic function of primary rat hepatocytes in engineered tissue constructs that otherwise exhibited suppressed function in their core.

Technology Isn't the Half of It: Integrating Electronic Health Records and Infusion Pumps in a Large Hospital.

BACKGROUND: Although adoption of "smart" infusion pumps has improved intravenous medication administration safety, pump integration with electronic health records (EHRs) remains rare. Early-adopter hospitals have recently implemented intravenous clinical integration (IVCI) to allow bidirectional communication between their EHRs and infusion pumps. However, the challenges and strategies involved in IVCI implementation have not been described. METHODS: A qualitative description of one hospital's IVCI implementation was conducted. The research team interviewed 33 pharmacists, technologists, clinicians, nurse managers, educators, and organizational leaders; observed nurses on five units using EHR-integrated pumps; and attended nurse training. Interview notes and transcripts were analyzed to describe IVCI implementation, highlighting its effects on clinicians and the organization. RESULTS: Motivations for implementation included a culture of innovation, simultaneous pump and EHR upgrades, and belief that IVCI would improve patient safety. Proactive planning included a simultaneous go-live across selected units, financial investment, multidisciplinary planning teams, and clinical training. Challenges included lack of direct communication between EHR and pump vendors, nonstandardized unit-specific drug libraries, and unit- and nurse-specific variation in workflows for administering infusions. Mitigation strategies included serving as messenger between vendors, conducting hospitalwide efforts to standardize drug libraries and workflows, and standardizing organizational policies. Lessons learned included that IVCI adoption was as much a nursing workflow and organizational policy intervention as a technological implementation. CONCLUSION: Integrating infusion pumps and EHRs involves much more than installing new technologies. Hospitals considering IVCI should prepare to undertake significant simultaneous changes to organizational policies and clinician workflows.

In situ expansion of engineered human liver tissue in a mouse model of chronic liver disease.

Control of both tissue architecture and scale is a fundamental translational roadblock in tissue engineering. An experimental framework that enables investigation into how architecture and scaling may be coupled is needed. We fabricated a structurally organized engineered tissue unit that expanded in response to regenerative cues after implantation into mice with liver injury. Specifically, we found that tissues containing patterned human primary hepatocytes, endothelial cells, and stromal cells in a degradable hydrogel expanded more than 50-fold over the course of 11 weeks in mice with injured livers. There was a concomitant increase in graft function as indicated by the production of multiple human liver proteins. Histologically, we observed the emergence of characteristic liver stereotypical microstructures mediated by coordinated growth of hepatocytes in close juxtaposition with a perfused vasculature. We demonstrated the utility of this system for probing the impact of multicellular geometric architecture on tissue expansion in response to liver injury. This approach is a hybrid strategy that harnesses both biology and engineering to more efficiently deploy a limited cell mass after implantation.

Patterning vascular networks in vivo for tissue engineering applications.

The ultimate design of functionally therapeutic engineered tissues and organs will rely on our ability to engineer vasculature that can meet tissue-specific metabolic needs. We recently introduced an approach for patterning the formation of functional spatially organized vascular architectures within engineered tissues in vivo. Here, we now explore the design parameters of this approach and how they impact the vascularization of an engineered tissue construct after implantation. We used micropatterning techniques to organize endothelial cells (ECs) into geometrically defined "cords," which in turn acted as a template after implantation for the guided formation of patterned capillaries integrated with the host tissue. We demonstrated that the diameter of the cords before implantation impacts the location and density of the resultant capillary network. Inclusion of mural cells to the vascularization response appears primarily to impact the dynamics of vascularization. We established that clinically relevant endothelial sources such as induced pluripotent stem cell-derived ECs and human microvascular endothelial cells can drive vascularization within this system. Finally, we demonstrated the ability to control the juxtaposition of parenchyma with perfused vasculature by implanting cords containing a mixture of both a parenchymal cell type (hepatocytes) and ECs. These findings define important characteristics that will ultimately impact the design of vasculature structures that meet tissue-specific needs.

Manipulation of 3D Cluster Size and Geometry by Release from 2D Micropatterns.

A novel method to control three-dimensional cell cluster size and geometry using two-dimensional patterning techniques is described. Cells were first cultured on two-dimensional micropatterned collagen using conventional soft lithography techniques. Collagenase was used to degrade the micropatterned collagen and release cells from the micropatterns, forming clusters of cells which were then resuspended in a three-dimensional collagen matrix. This method facilitated the formation of uniformly sized clusters within a single sample. By systematically varying the geometry of the two-dimensional micropatterned islands, final cluster size and cell number in three dimensions could be controlled. Using this technique, we showed that proliferation of cells within collagen gels depended on the size of clusters, suggesting an important role for multicellular structure on biological function. Furthermore, by utilizing more complex two-dimensional patterns, non-spherical structures could be produced. This technique demonstrates a simple way to exploit two-dimensional micro-patterning in order to create complex and structured multicellular clusters in a three-dimensional environment.