Treatment of Massive Irreparable Rotator Cuff Tears: A Cost-effectiveness Analysis.

Massive irreparable rotator cuff tears cause significant shoulder pain and dysfunction. Physical therapy (PT), arthroscopic debridement with biceps tenotomy (AD-BT), and hemiarthroplasty (HA) are treatments shown to reduce pain and improve quality of life. Reverse total shoulder arthroplasty (RTSA) is a newer surgical treatment option that may offer improved function. A cost-effectiveness analysis of these interventions has never been performed, and no head-to-head comparative effectiveness trials currently exist. A Markov decision analytic model was used to compare RTSA, HA, AD-BT, and PT as treatments for elderly patients with massive irreparable rotator cuff tears. Probabilities for complications, perioperative death, conversion procedures, and reoperations were derived from the literature, and costs were determined by average Medicare reimbursement rates from 2011. Reverse total shoulder arthroplasty yielded the most quality-adjusted life years (QALY) with 7.69, but greater benefits came at higher costs compared with other treatments. Sensitivity analyses showed that PT was the most cost-effective intervention at a health utility of 0.75 or greater (QALY 7.35). The health utility of RTSA was 0.72 or less (QALY 7.48) or RTSA probability of no complications was 0.83 or less (QALY 7.48 at cost of $23,830). Reverse total shoulder arthroplasty yielded benefits at a cost considered good value for money compared with other treatments. Reverse total shoulder arthroplasty is the preferred and most cost-effective treatment option for elderly patients with massive irreparable rotator cuff tears. For patients seeking pain relief without functional gains, AD-BT can be considered a cost-effective and cheaper alternative. The cost-effectiveness analysis approach can help guide clinical practice as well as the policies of health care systems and insurers. [Orthopedics. 2017; 40(1):e65-e76.].

Out-of-pocket Cost Burden in Pediatric Inflammatory Bowel Disease: A Cross-sectional Cohort Analysis.

BACKGROUND: Pediatric inflammatory bowel disease (IBD), consisting of Crohn's disease (CD) and ulcerative colitis (UC), can result in significant morbidity requiring frequent health care utilization. Although it is known that the overall financial impact of pediatric IBD is significant, the direct out-of-pocket (OOP) cost burden on the parents of children with IBD has not been explored. We hypothesized that affected children with a more relapsing disease course and families in lower income strata, ineligible for need-based assistance programs, disparately absorb ongoing financial stress. METHODS: We completed a cross-sectional analysis among parents of children with IBD residing in California using an online HIPAA-secure Qualtrics survey. Multicenter recruitment occurred between December 4, 2013 and September 18, 2014 at the point-of-care from site investigators, informational flyers distributed at regional CCFA conferences, and social media campaigns equally targeting Northern, Central, and Southern California. IBD-, patient-, and family-specific information were collected from the parents of pediatric patients with IBD patients younger than 18 years of age at time of study, carry a confirmed diagnosis of CD or UC, reside in and receive pediatric gastroenterology care in California, and do not have other chronic diseases requiring ongoing medical care. RESULTS: We collected 150 unique surveys from parents of children with IBD (67 CD; 83 UC). The median patient age was 14 years for both CD and UC, with an overall 3.7 years (SD 2.8 yr) difference between survey completion and time of IBD diagnosis. Annually, 63.6%, 28.6%, and 5.3% of families had an OOP cost burden >$500, >$1000, and >5000, respectively. Approximately one-third (36.0%) of patients had emergency department (ED) visits over the past year, with 59.2% of these patients spending >$500 on emergency department copays, including 11.1% who spent >$5000. Although 43.3% contributed <$500 on procedure and test costs, 20.0% spent >$2000 in the past year. Families with household income between $50,000 and $100,000 had a statistically significant probability (80.6%) of higher annual OOP costs than families with lower income <$50,000 (20.0%; P < 0.0001) or higher income >$100,000 (64.6%; P < 0.05). Multivariate analysis revealed that clinical variables associated with uncontrolled IBD states correlated to higher OOP cost burden. Annual OOP costs were more likely to be >$500 among patients who had increased spending on procedures and tests (odds ratio [OR], 5.63; 95% confidence interval [CI], 2.73-11.63), prednisone course required over the past year (OR, 3.19; 95% CI, 1.02-9.92), at least 1 emergency department visit for IBD symptoms (OR, 2.84; 95% CI, 1.33-6.06), at least 4 or more outpatient primary medical doctor visits for IBD symptoms (OR, 2.82; 95% CI, 1.40-5.68), and history of 4 or more lifetime hospitalizations for acute IBD care (OR, 2.60; 95% CI, 1.13-5.96). CONCLUSIONS: Previously undocumented, a high proportion of pediatric IBD families incur substantial OOP cost burden. Patients who are frequently in relapsing and uncontrolled IBD states require more acute care services and sustain higher OOP cost burden. Lower middle income parents of children with IBD ineligible for need-based assistance may be particularly at risk for financial stress from OOP costs related to ongoing medical care.

Utilization trends of anti-TNF agents and health outcomes in adults and children with inflammatory bowel diseases: a single-center experience.

BACKGROUND: Utilization trends and health effects of infliximab and adalimumab in inflammatory bowel disease (IBD) are incompletely understood. We aimed to describe utilization trends of these 2 anti-tumor necrosis factor (TNF) agents, determine the correlation between utilization with rates of hospitalization and surgery and describe differences in use between adults and children. METHODS: Longitudinal data were analyzed for drug utilization, hospitalization, and abdominal surgery. Descriptive statistics were used to show trends, and utilization quotients were compared for standardization. Multivariate logistic regression analysis assessed the association between drug use and rates of hospitalization and surgery. RESULTS: Four hundred thirty-eight pediatric and 2514 adult patients with IBD generated a total of 51,882 inpatient and outpatient encounters, representing 1185 Crohn's disease, 1531 ulcerative colitis, and 236 indeterminate colitis patients. From 2007 through 2012, utilization quotients declined for hospitalization but remained unchanged for surgery; adalimumab saw a 3-fold increase, despite continued dominance of infliximab. Median band and mean fitted plots showed downward hospitalization trends from 2006 to 2012. Utilization of infliximab peaked in 2008, Q4 with gradual decline to 2012, Q2; and adalimumab showed moderate increased utilization since 2007, Q1. Use of infliximab (odds ratio [OR], 0.76; 95% confidence interval [CI], 0.70-0.83) and adalimumab (OR, 0.79; 95% CI, 0.72-0.87) was associated with decreased hospitalization risk but not associated with reduced abdominal surgery risk. Children had increased hospitalization (OR, 2.68; 95% CI, 2.49-2.88) but decreased risk for abdominal surgery (OR, 0.57; 95% CI, 0.46-0.70). CONCLUSIONS: Current infliximab use remains substantially greater than adalimumab use, despite recent increased use of adalimumab. Although trends for hospitalization for IBD are decreasing, it is not reflected in abdominal surgery rates in a tertiary IBD referral center.

Characteristics and direct costs of academic pediatric subspecialty outpatient no-show events.

BACKGROUND: Clinic no shows (NS) create a lost opportunity for provider-patient interaction and impose a financial burden to the healthcare system and on society. We aimed to: (1) to determine the clinical and demographic factors associated with increased NS rates at a children's hospital's subsubspecialty clinics and (2) to estimate the direct institutional financial costs associated with NS events. METHODS: A comprehensive database was generated from all clinic encounters for 15 subspecialty outpatient clinics (five surgical and 10 medical) between September 12, 2005 and December 30, 2010. Multivariate logistic regressions were performed to identify the variables associated with NS events. Direct costs of NS events were estimated using annual revenue for each clinic. RESULTS: A total of 284,275 encounters and 17,024 NS events were available for analysis. Public insurance coverage (Medicaid and Title V), compared to private insurance or self-pay status, was associated with an increased likelihood NS (OR 2.19, 95% CI 2.10-2.28, p < 0.0005 for Medicaid; OR 1.56, 95% CI 1.50-1.62, p < 0.0005 for Title V). Compared to patients 21-30 years of age, patients <12 years (OR 2.08, 95% CI 1.77-2.45, p < 0.0005) had increased likelihood of NS. Scheduled visits with medical subspecialists were more likely than surgical subspecialty visits to result in a NS (OR 1.69, 95% CI 1.63-1.75, p < 0.0005). The predicted annualized lost revenue associated with NS visits was estimated at $730,000 from the 15 clinics analyzed, approximately $210 per NS event. CONCLUSION: Pediatric subspecialty NS events are common, costly, and potentially preventable.

Non-drug costs associated with outpatient infliximab administration in pediatric inflammatory bowel disease.

BACKGROUND: Infliximab is the most widely used biological agent for Crohn's disease (CD) and ulcerative colitis (UC) but requires outpatient infusion units because of its intravenous administration requirement. The aim of this study was (1) to determine the average non-drug costs associated with each outpatient use of infliximab for pediatric inflammatory bowel disease and (2) to determine the proportion of non-drug costs associated with each outpatient infliximab use relative to the total cost of each encounter. METHODS: Hospital administrative and pharmacy databases were queried for all short stay unit encounters at Lucile Packard Children's Hospital at Stanford University linked to infliximab infusions for inflammatory bowel disease between January 1, 2006, and December 31, 2011. Infliximab drug and non-drug costs associated with CD and UC were compared. RESULTS: A total of 771 unique encounters were generated for 76 pediatric patients (53 CD, 23 UC). For direct costs related to infliximab infusions for either CD or UC patients, more than 77% of the total health care costs per encounter were related to personnel (e.g., nursing), facility operations, and laboratory costs. Only 23% of the total costs were related to the actual infliximab drug costs. Based on an 80/20 payor mix of managed care versus government-subsidized insurance payers, 24.5% of the total reimbursements were applied to non-drug costs in CD and 20.9% in UC. CONCLUSIONS: Non-drug costs represent a substantial proportion of the total cost of outpatient infliximab-related actual costs in inflammatory bowel disease. Personnel costs represent the largest segment of the non-drug costs. The actual drug costs of infliximab represent a small proportion of the total costs.

Microfluidic diffusive filter for apheresis (leukapheresis).

Apheresis is a procedure used to fractionate whole blood into its individual components. Following fractionation, the desired component is isolated and the remaining blood in many cases is returned to the donor. Leukapheresis is one type of apheresis where leukocytes (white blood cells) are selectively removed. This procedure is commonly used for blood transfusions to remove donor leukocytes from being transferred to the recipient. Apheresis also has several therapeutic applications. In this manuscript we discuss the design, fabrication and testing of a continuous flow diffusive filter, fabricated using simple soft lithographic techniques for depletion of leukocytes. This device employs micro sieves that exploit the size and shape difference between the different cell types to obtain depletion of leukocytes from whole blood. Currently, conventional apheresis methods like centrifugation or fiber mesh filtration are commonly used. A theoretical model was developed to determine the optimal shape of the diffuser to ensure that the volumetric flow through individual sieve elements is equal. This device was designed to serve as a passive device that does not require any external manipulation. Results show that for the given device design, isolation of approximately 50% of the inlet erythrocytes (red blood cells), along with depletion of >97% of the inlet leukocytes is possible at a flow rate of 5 microl min(-1). Simple modifications to the geometry and dimensions of the sieves can be made to obtain isolation of plasma.

Enrichment using antibody-coated microfluidic chambers in shear flow: model mixtures of human lymphocytes.

Isolation of phenotypically-pure cell subpopulations from heterogeneous cell mixtures such as blood is a difficult yet fundamentally important task. Current techniques such as fluorescent activated cell sorting (FACS) and magnetic-activated cell sorting (MACS) require pre-incubation with antibodies which lead to processing times of at least 15-60 min. In this study, we explored the use of antibody-coated microfluidic chambers to negative deplete undesired cell types, thus obtaining an enriched cell subpopulation at the outlet. We used human lymphocyte cell lines, MOLT-3 and Raji, as a model system to examine the dynamic cell binding behavior on antibody coated surfaces under shear flow. Shear stress ranging between 0.75 and 1.0 dyn/cm2 was found to provide most efficient separation. Cell adhesion was shown to follow pseudo-first order kinetics, and an anti-CD19 coated (Raji-depletion) device with approximately 2.6 min residence time was demonstrated to produce 100% pure MOLT-3 cells from 50-50 MOLT-3/Raji mixture. We have developed a mathematical model of the separation device based on the experimentally determined kinetic parameters that can be extended to design future separation modules for other cell mixtures. We conclude that we can design microfluidic devices that exploits the kinetics of dynamic cell adhesion to antibody coated surfaces to provide enriched cell subpopulations within minutes of total processing time.

Development of a microfabricated cytometry platform for characterization and sorting of individual leukocytes.

Organizing leukocytes into high-density arrays makes these cells amenable to rapid optical characterization and subsequent sorting, pointing to clinical and basic science applications. The present paper describes development of a cytometry platform for creating high-density leukocyte arrays and demonstrates retrieval of single cells from the array. Poly(ethylene glycol)(PEG) photolithography was employed to fabricate arrays of microwells composed of PEG hydrogel walls and glass attachment pads 20 microm x 20 microm and 15 microm x 15 microm in size. PEG micropatterned glass surfaces were further modified with cell-adhesive ligands, poly-L-lysine, anti-CD5 and anti-CD19 antibodies, in order to engineer specific cell-surface interactions within the individual wells. Localization of the fluorescently-labeled proteins in the glass attachment pads of PEG microwells was visualized by fluorescence microscopy. Glass slides micropatterned with PEG and cell-adhesive ligands were exposed to T-lymphocytes for 30 min. These anchorage-independent cells became selectively captured in the ligand-modified microwells forming high-density cell arrays. Cell occupancy in the microwells was found to be antibody-dependent, reaching 94.6 +/- 2.3% for microwells decorated with T-cell specific anti-CD5 antibodies. Laser capture microdissection (LCM) was investigated as a method for sorting cells from the array and retrieval of single selected cells was demonstrated.

Effect of flow and surface conditions on human lymphocyte isolation using microfluidic chambers.

Phenotypically pure subpopulations of lymphocytes can provide valuable insights into the immune response to injury and disease. The isolation of these subpopulations presents unique challenges, particularly when preprocessing incubation to attach fluorescent or antibody tags is to be minimized. This paper examines the separation of T and B lymphocytes from mixtures using microfluidic chambers coated with antibodies, focusing on flow conditions and surface chemistry. The adhesion of both cell types decreases as shear stress increases irrespective of the surface chemistry. The incorporation of poly(ethylene glycol) chains along with the antibodies on the chamber surface is shown to significantly improve the reproducibility of cell adhesion and is thus an important part of the overall system design. Furthermore, this technique is shown to be an effective way of isolating highly pure subpopulations of lymphocytes from model mixtures, even when the target cell concentration is low.

Development of a microscale cell culture analog to probe naphthalene toxicity.

Prediction of human response to drugs or chemicals is difficult as a result of the complexity of living organisms. We describe an in vitro model that can realistically and inexpensively study the adsorption, distribution, metabolism, elimination, and potential toxicity (ADMET) of chemicals. A microscale cell culture analog (microCCA) is a physical replica of the physiologically based pharmacokinetics (PBPK) model. Such a microfabricated device consists of a fluidic network of channels to mimic the circulatory system and chambers containing cultured mammalian cells representing key functions of animal "organ" systems. This paper describes the application of a two-cell system, four-chamber microCCA ("lung"-"liver"-"other tissue"-"fat") device for proof-of-concept study using naphthalene as a model toxicant. Naphthalene is converted into reactive metabolites (i.e., 1,2-naphthalenediol and 1,2-naphthoquinone) in the "liver" compartment, which then circulate to the "lung" depleting glutathione (GSH) in lung cells. Such microfabricated in vitro devices are potential human surrogates for testing chemicals and pharmaceutics for toxicity and efficacy.

The design and fabrication of three-chamber microscale cell culture analog devices with integrated dissolved oxygen sensors.

Whole animal testing is an essential part in evaluating the toxicological and pharmacological profiles of chemicals and pharmaceuticals, but these experiments are expensive and cumbersome. A cell culture analog (CCA) system, when used in conjunction with a physiologically based pharmacokinetic (PBPK) model, provides an in vitro supplement to animal studies and the possibility of a human surrogate for predicting human response in clinical trials. A PBPK model mathematically simulates animal metabolism by modeling the absorption, distribution, metabolism, and elimination kinetics of a chemical in interconnected tissue compartments. A CCA uses mammalian cells cultured in interconnected chambers to physically represent the corresponding PBPK. These compartments are connected by recirculating tissue culture medium that acts as a blood surrogate. The purpose of this article is to describe the design and basic operation of the microscale manifestation of such a system. Microscale CCAs offer the potential for inexpensive, relatively high throughput evaluation of chemicals while minimizing demand for reagents and cells. Using microfabrication technology, a three-chamber ("lung"-"liver"-"other") microscale cell culture analog (microCCA) device was fabricated on a 1 in. (2.54 cm) square silicon chip. With a design flow rate of 1.76 microL/min, this microCCA device achieves approximate physiological liquid-to-cell ratio and hydrodynamic shear stress while replicating the liquid residence time parameters in the PBPK model. A dissolved oxygen sensor based on collision quenching of a fluorescent ruthenium complex by oxygen molecules was integrated into the system, demonstrating the potential to integrate real-time sensors into such devices.

A self-priming microfluidic diaphragm pump capable of recirculation fabricated by combining soft lithography and traditional machining.

Fluid transport is crucial in the development of microanalytical devices. While there are many micropump designs available, most are incapable of sustaining recirculation of fluid at microL/min to mL/min levels. We have designed and fabricated a positive displacement micropump by combining soft lithography with traditional bulk machining. The micropump is actuated through pneumatic pressure. The pump is self-priming and is suitable for recirculating fluid through a microfluidic device containing mammalian cell culture. By custom designing the volume of the pumping chamber, tight control of the output flow rate can be obtained by changing the actuation frequency. It can also be fabricated easily on plastic substrates without access to expensive microfabrication equipment.