Positive Charge Influences on the Surface Interactions and Cohesive Bonding of a Catechol-Containing Polymer

Achieving robust underwater adhesion remains challenging. Through generations of evolution, marine mussels have developed an adhesive system that allows them to anchor onto wet surfaces. Scientists have taken varied approaches to developing mussel-inspired adhesives. Mussel foot proteins are rich in lysine residues, which may play a role in the removal of salts from surfaces. Displacement of water and ions on substrates could then enable molecular contact with surfaces. The necessity of cations for underwater adhesion is still in debate. Here, we examined the performance of a methacrylate polymer containing quaternary ammonium and catechol groups. Varying amounts of charge in the polymers were studied. As opposed to protonated amines such as lysine, quaternary ammonium groups offer a nonreactive cation for isolating effects from only charge. Results shown for dry bonding demonstrated that cations tended to decrease bulk cohesion while increasing surface interactions. Stronger interactions at surfaces, along with weaker bulk bonding, indicate that cations decreased the cohesive forces. When under salt water, overall bulk adhesion also dropped with higher cation loadings. Surface attachment under salt water also dropped, indicating that the polymer cations could not displace surface waters or sodium ions. Salt did, however, appear to shield bulk cation-cation repulsions. These studies help to distinguish influences upon bulk cohesion from attachment at surfaces. The roles of cations in adhesion are complex, with both cohesive and surface bonding being relevant in different ways, sometimes even working in opposite directions.

Trends in utilization, demographics, and costs of platelet-rich plasma injections: a ten-year nationwide investigation

INTRODUCTION

Platelet-Rich Plasma (PRP) has become one of the most popular biologic treatments in orthopedic surgery. Despite this, its utilization over the last decade has not been investigated.

METHODS

We conducted a search using Current Procedural Terminology codes to identify patients who received PRP injections between 2010 and 2019 using the PearlDiver database. The purpose was to 1) determine annual trends of PRP injections of the ankle, hip, knee, shoulder, and elbow for cartilaginous, tendinous, ligamentous, meniscal/labral, and miscellaneous pathologies; 2) compare baseline demographics of patients receiving these injections; and 3) analyze costs.

RESULTS

A total of 23,716 patients who received PRP injections were identified; 54.4% were female. The incidence of PRP injections was between 1.6 and 4.3 per 100,000 orthopedic patients. The most common anatomic locations targeted for PRP therapy was the knee (36.7%), followed by the shoulder/elbow (30.5%), then the ankle (19.6%) and hip (13.6%). Subgroup analysis revealed that most common use of PRP was for knee cartilaginous pathologies, followed by shoulder/elbow tendinous pathologies. The number of injections used in the knee significantly increased between 2010 and 2019 (p< 0.001), and trended toward significantly increasing in the shoulder/elbow (p = 0.055). Average annual costs for PRP injections ranged from $711.65 for ankles and $1,711.63 for hips; costs significantly changed for 3 of the 4 anatomic locations. By 2019, average PRP injection costs for each area clustered around $1000.

CONCLUSION

Between 2010 and 2019, there was an increase in usage of PRP injections in the knee (cartilaginous pathologies) and the shoulder/elbow (tendinous pathologies). PRP costs demonstrated early variability but clustered around $1000 by 2019. Further studies into drivers of prices and cost-effectiveness of PRP are needed to provide clarity into the true costs to patients and healthcare providers.

Socioeconomic Disparities in Surgical Care for Congenital Hand Differences

BACKGROUND

The purpose of this study was to evaluate the influence of socioeconomic factors on access to congenital hand surgery care, hospital admission charges, and analyze these geographic trends across regions of the country.

METHODS

Retrospective cohort study was conducted of congenital hand surgery performed in the United States from 2010 through 2020 using the Pediatric Health Information System. Multivariate regression was used to analyze the impact of socioeconomic factors.

RESULTS

During the study interval, 5531 pediatric patients underwent corrective surgery for congenital hand differences, including syndactyly repair (n = 2439), polydactyly repair (n = 2826), and pollicization (n = 266). Patients underwent surgery at significantly earlier age when treated at above-median case volume hospitals (P < .001). Patients with above-median income (P < .001), non-white race (P < .001), commercial insurance (P < .001), living in an urban community (P < .001), and not living in an underserved area (P < .001) were more likely to be treated at high-volume hospitals. Nearly half of patients chose to seek care at a distant hospital rather than the one locally available (49.5%, n = 1172). Of those choosing a distant hospital, most patients chose a higher-volume facility (80.9%, n = 948 of 1172). On multivariate regression, white patients were significantly more likely to choose a more distant, higher-volume hospital (P < .001).

CONCLUSIONS

Socioeconomic and geographic factors significantly contribute to disparate access to congenital hand surgery across the country. Patients with higher socioeconomic status are more likely to be treated at high-volume hospitals. Treatment at hospitals with higher case volume is associated with earlier age at surgery and decreased hospital admission charges.

The Impact of Relocating a Trauma Center: Retrospective Observations on Payer Demographics and Cost-Analysis

BACKGROUND

Standardization of trauma centers improves quality of care, yet that comes with financial challenges. The decision to designate a trauma center typically focuses on access, quality of care, and the needs of the local community, but less often considers the financial viability of the trauma center. A level-1 trauma center was relocated in 2017 and this presented an opportunity to compare financial data at two separate locations in the same city.

METHODS

A retrospective review was performed on the local trauma registry and billing database in all patients aged ≥19 years on the trauma service before and after the move.

RESULTS

3041 patients were included (pre-move: 1151; post-move: 1890). After the move, patients were older (9.5 years), and more were females (14.9%) and white (16.5%). Increases in blunt injuries (7.6%), falls (14.8%), and motor vehicle accidents (1.7%) were observed after the move. After the move, patients were less likely to be discharged home (6.5%) and more likely to go to a skilled nursing facility (3%) or inpatient rehabilitation (5.5%). Post-move more patients had Medicare (12.6%) or commercial (8.5%) insurance and charges per patient decreased by $2,833, while charges collected per patient increased by $2425. Patients were seen from a broader distribution of zip codes post-move.

DISCUSSION

Relocating a trauma center did improve financial viability for this institution. Future studies should consider the impact on the surrounding community and other trauma centers.

LEVEL OF EVIDENCE

Level IV.

The Impact of Injectable Opioid Agonist Treatment (iOAT) on Involvement in Criminalized Activities: A Secondary Analysis from a Clinical Trial in Vancouver, BC

Purpose

A significant portion of the economic consequences of untreated Opioid Use Disorder (OUD) relate to individuals' involvement in the criminal justice system. The present study uncovers if treatment with iOAT is related to the number of criminal charges amongst participants, what type of crime participants were involved in, and the frequency with which participants were victims of crime. This study contributes to the body of research on the effectiveness of iOAT reducing criminal involvement.

Patients and Methods

This is a secondary analysis of police record data obtained from the Vancouver Police Department over a three-year period during the Study to Assess Longer-term Opioid Medication Effectiveness clinical trial. The data was obtained from participants (N = 192) enrolled in the trial through a release of information form.

Results

During the three-year period, most charges (45.6%) were property offences, and 25.5% of participants were victims of crime. Participants with no treatment prior to randomization into the SALOME trial were 2.61 (95% CI = 1.64-4.14) more likely to have been charged with a crime than during the iOAT state.

Conclusion

IOAT can reduce individuals' involvement with the criminal justice system and is thus a crucial part of the continuum of care. Addiction should be conceptualized as a healthcare rather than criminal issue.

Variation in Hospitalization Costs, Charges, and Lengths of Hospital Stay for Coronavirus Disease 2019 Patients Treated With Venovenous Extracorporeal Membrane Oxygenation in the United States: A Cohort Study

OBJECTIVES

The aim was to characterize hospitalization costs, charges, and lengths of hospital stay for COVID-19 patients treated with venovenous (VV) extracorporeal membrane oxygenation (ECMO) in the United States during 2020. Secondarily, differences in hospitalization costs, charges, and lengths of hospital stay were explored based on hospital-level factors.

DESIGN

Retrospective cohort study.

SETTING

Multiple hospitals in the United States.

PARTICIPANTS

Adult patients with COVID-19 who were on VV ECMO in 2020 and had data in the national inpatient sample.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Demographics and baseline comorbidities were recorded for patients. Primary study outcomes were hospitalization costs, charges, and lengths of hospital stay. Study outcomes were compared after stratification by hospital region, bed size, and for-profit status. The median hospitalization cost for the 3,315-patient weighted cohort was $200,300 ($99,623, $338,062). Median hospitalization charges were $870,513 ($438,228, $1,553,157), and the median length of hospital stay was 30 days (17, 46). Survival to discharge was 54.4% for all patients in the cohort. Median hospitalization cost differed by region (p = 0.01), bed size (p < 0.001), and for-profit status (p = 0.02). Median hospitalization charges also differed by region (p = 0.04), bed size (p = 0.002), and for-profit status (p < 0.001). Length of hospital stay differed by region (p = 0.03) and bed size (p < 0.001), but not for-profit status (p = 0.40). Hospitalization costs were the lowest, and charges were highest in private-for-profit hospitals. Large hospitals also had higher costs, charges, and hospital stay lengths than small hospitals.

CONCLUSIONS

In this retrospective cohort study, hospitalization costs and charges for patients with COVID-19 on VV ECMO were found to be substantial but similar to what has been reported previously for patients without COVID-19 on VV ECMO. Significant variation was observed in costs, charges, and lengths of hospital stay based on hospital-level factors.

Time is money: Examining the time cost and associated charges of common performance validity tests

Objective: This study presents data on the time cost and associated charges for common performance validity tests (PVTs). It also applies an approach from cost effectiveness research to comparison of tests that incorporates cost and classification accuracy. Method: A recent test usage survey was used to identify PVTs in common use among adult neuropsychologists. Data on test administration and scoring time were aggregated. Charges per test were calculated. A cost effectiveness approach was applied to compare pairs of tests from three studies using data on test administration time and classification accuracy operationalized as improvement in posterior probability beyond base rate. Charges per unit increase in posterior probability over base rate were calculated for base rates of invalidity ranging from 10 to 40%. Results: Ten commonly used PVTs measures showed a wide range in test administration and scoring time from 1 to 3 minutes to over 40 minutes with associated charge estimates from $4 to $284. Cost effectiveness comparisons illustrated the nuance in test selection and benefit of considering cost in relation to outcome rather than prioritizing time (i.e. cost minimization) classification accuracy alone. Conclusions: Findings extend recent research efforts to fill knowledge gaps related to the cost of neuropsychological evaluation. The cost effectiveness approach warrants further study in other samples with different neuropsychological and outcome measures.

Incidence, predictors, clinical outcomes, and economic burden of recurrent acute kidney injury: a retrospective cohort study

OBJECTIVE

This study aimed to assess the incidence, predictors, mortality, and economic outcomes of recurrent Acute kidney injury (AKI) in Jordan.

METHODS

This was a retrospective cohort study that included adult patients who were admitted with AKI to university hospitals in the country from 2010-2019. Recurrent episodes of AKI, laboratory data, baseline medication list, and death dates were retrieved from patient's medical records. The incidence rate of recurrent AKI was estimated. Predictors of recurrent AKI and mortality during the five years post-discharge was evaluated. Total admission charges were described and evaluated in total and by service provided.

RESULTS

Among 1162 AKI patients, 57 patients (4.9%) died during the index admission (first admission during the study period), and among the survivors, 220 patients were re-hospitalized with a recurrent AKI during five years of follow-up. Patients with higher discharge serum creatinine level (SCr) at index admission had higher odds of AKI recurrence (OR = 1.001). Patients who were on respiratory, antineoplastic, or anticoagulant medications were also more susceptible to recurrence; ORs were 1.69, 2.77, and 4.16, respectively. Patients who were elderly, with recurrent AKI episodes, or with a more extended hospital stay at index admission were more likely to die during the five years post discharge. The median charge of recurrent admissions was higher than the median charge of the index admissions; 1519.17 JOD ($2142.7) versus 1362.85 JOD ($1922.2), respectively.

CONCLUSIONS

Recurrent AKI is associated with increased mortality and health expenditures. Higher discharge SCr levels at index admission, and chronic comorbidities are associated with a higher likelihood of AKI recurrence.

Clinical Outcomes and Direct Medical Expenditures Associated With Intensive Care Unit Admission for Inpatients With COVID-19 in Jordan: A Retrospective Cohort Study

OBJECTIVES

This study aimed to describe clinical outcomes and medical expenditures associated with COVID-19 admissions. In addition, this study aimed to investigate the impact of patients' characteristics and baseline comorbidities on intensive care unit (ICU) admission, mortality, and medical expenditures for hospitalized patients with COVID-19.

METHODS

This retrospective cohort study included all hospitalized patients with confirmed COVID-19 in Prince Hamza Hospital and King Abdullah University Hospital, during the period from March 2020 to June 2021. Medical records and pharmacy data were followed and reviewed throughout their admissions. The ICU admission, inpatient mortality, hospital length of stay, and inpatient charges were described. Predictors of ICU admission and inpatient charges were evaluated.

RESULTS

A total of 7694 COVID-19 hospital admissions were included. Approximately 1189 patients (15.5%) were admitted to ICU and 21.4% died in the hospital. The fatality rate among those admitted to ICU was 82.6% compared with 10.2% for non-ICU admitted patients. The average admission charge and charge per admission day were 1598.2 and 200.2 Jordanian dinar, respectively, and both charges were higher in ICU admitted patients than non-ICU admitted patients. Being older in age, smoker or ex-smoker, and having chronic diseases were all significantly associated with a higher likelihood of ICU admission and mortality among admitted patients.

CONCLUSIONS

ICU admission in patients with COVID-19 is associated with poor clinical outcomes and substantial medical expenditures and is more likely among older adults, smokers, and those with chronic diseases.

Comparison shopping: Is neuropsychological evaluation more expensive than neuroimaging?

OBJECTIVE

This study empirically examined if neuropsychological evaluation (NPE) is expensive compared to other diagnostic procedures such as neuroimaging.

METHOD

We aggregated data on charges for NPE and common neuroimaging procedures (e.g., head CT and brain MRI) from hospitals in the U.S. Charges for five-hour NPE and eight-hour NPE were compared to charges for head CT and brain MRI, respectively. Difference scores were calculated between five-hour NPE and head CT and between eight-hour NPE and brain MRI. A charge difference of $250 or less was considered minimal. NPE and neuroimaging charges were compared across U.S. regions.

RESULTS

Median head CT charges were $1942 to $2699. Median brain MRI charges were $3103 to $4487. Median five-hour NPE charges were $1855 to $1977. Median eight-hour NPE charges were $2757 to $2917. Head CT and five-hour NPE charges were not significantly different. Eight-hour NPE and brain MRI charges were not significantly different. Charge differences between five-hour NPE and head CT were minimal in 32.3% of hospitals. Charge differences between eight-hour NPE and brain MRI were minimal in 21.2% of hospitals. U.S. regions were not significantly different in charges for NPE or neuroimaging.

CONCLUSIONS

Findings provide preliminary data on charges for NPE in relation to charges for common imaging procedures. NPE does not appear to be more expensive than neuroimaging and, in fact, appears comparable. Future research might expand the information on NPE charges to include additional settings.

Machine Learning Assisted Screening of Two-Dimensional Materials for Water Desalination

There exists a vast expanse of data in the literature which can be harnessed for accelerated design and discovery of advanced materials for various applications of importance ─ for example, desalination of seawater. Here, we develop a machine learning (ML) model, training it with ∼260 molecular dynamics (MD) computation results, to predict the desalination performance of 2D membranes that exist in the literature. The desalination performance variables of water flux and salt rejection rates are correlated to 49 material features related to the chemistry of the pores and the membranes along with applied pressure, salt concentration, partial charges on the atoms, geometry of the pore, the mechanical properties of the membranes, and the properties of water for the water model used. We used the ML model to screen 3814 structurally optimized 2D materials for maximum water flux and salt rejection rates from the literature. We found some candidates that perform ∼4 times better than the more popularly known 2D materials such as graphene and MoS₂. This result is verified using data obtained from MD simulations performed on several representative 2D membranes for different classes. Such validated statistical frameworks using literature data can be very useful in guiding experiments in the field of functional materials for varied applications.

UPCODING MEDICARE: IS HEALTHCARE FRAUD AND ABUSE INCREASING?

Medicare fraud has been the cause of up to $60 billion in overpaid claims in 2015 alone. Upcoding occurs when a healthcare provider has submitted codes for more severe conditions than diagnosed for the patient to receive higher reimbursement. The purpose of this study was to assess the impact of Medicare and Medicaid fraud to determine the magnitude of upcoding inpatient and outpatient claims throughout reimbursements. The methodology for this study utilized a literature review. The literature review analyzed physician upcoding throughout present on admission infections, diagnostic related group upcoding, emergency department, and clinic upcoding. It was found that upcoding has had an impact on Medicare payments and fraud. Medicare fraud has been reported to be the magnitude of upcoding inpatient and outpatient claims throughout Medicare reimbursements. In addition, fraudulent activity has increased with upcoding for ambulatory inpatient and outpatient charges for patients with Medicare and Medicaid.

Analysis of Charges and Payments for Outpatient Arthroscopic Meniscectomy From 2005 to 2014: Hospital Reimbursement Increased Steadily as Surgeon Payments Declined

Background:

Charge and reimbursement trends for arthroscopic partial meniscectomies among orthopaedic surgeons, anesthesiologists, and hospital/surgery centers have not been formally analyzed, even though meniscectomies are the most commonly performed orthopaedic surgery.

Purpose:

To analyze Medicare charge and reimbursement trends for surgeons, anesthesiologists, and hospital/surgery centers for outpatient arthroscopic partial meniscectomies performed in the United States.

Study Design:

Economic and decision analysis; Level of evidence, 4.

Methods:

We analyzed trends in surgeon, anesthesiologist, and hospital charges and reimbursements for outpatient isolated arthroscopic partial meniscectomies from 2005 to 2014. Current Procedural Terminology codes were used to capture charge and reimbursement information using the nationally representative 5% Medicare sample. National and regional trends for charge, reimbursement, and Charlson Comorbidity Index (CCI) were evaluated using linear regression analysis.

Results:

A total of 31,717 patients were analyzed in this study. Charges across all groups increased significantly (P < .001) during the 10-year study period, with an increase of 18.4% ($2754-$3262) for surgeons, 85.5% ($802-$1480) for anesthesiologists, and 116.8% ($2743-$5947) for hospitals. Surgeon reimbursements declined by 15.5% ($504-$426; P = .072) during this period. Anesthesiologist and hospital reimbursements increased significantly during by 36.5% ($133-$182; P < .001) and 28.9% ($1540-$1984; P < .001) during the 10-year study period, respectively. The annual incidence of partial meniscectomies per 10,000 database patients decreased significantly from 18.3 to 15.6 over the course of the study (14.8% decrease; P = .009), while the CCI did not change significantly (P = .798).

Conclusion:

Hospital and anesthesiologist Medicare reimbursements for outpatient arthroscopic partial meniscectomies increased significantly, while surgeon reimbursements decreased. In 2005, hospitals were reimbursed 205% more ($1540 vs $504) than surgeons, and by 2014, they were reimbursed 365% more ($1984 vs $426), indicating that the gap between hospital and surgeon reimbursement is rising. Improved understanding of charge and reimbursement trends represents an opportunity for key stakeholders to improve financial alignment across the field of orthopaedics.

Predictors, rates, and trends of opioid use disorder among patients hospitalized with chronic pancreatitis

Background

Patients with chronic pancreatitis (CP) suffer from pain and receive increased opioid prescriptions with a high risk of opioid use disorder (OUD). We studied the predictors, trends and outcomes of OUD among patients hospitalized with CP.

Methods

Records with CP (with/without OUD) were extracted from the Nationwide Inpatient Sample (NIS) 2012-2014, and the association of OUD with the burden of CP was calculated. We then charted the trends of OUD and its interaction with concomitant CP from NIS 2007-2014 (SAS 9.4).

Results

In the period 2012-2014, 4349 (4.99%) of the 87,068 CP patients had concomitant OUD, with higher risk among patients who were young, females, white vs. Hispanics, and individuals with chronic back pain, arthritis, non-opioid substance use, mental health disorders, and those hospitalized in urban centers. OUD was associated with a longer hospital stay (6.9 vs. 6.5 days, P=0.0015) but no significant difference in charges ($47,151 vs. $49,017, P=0.0598) or mortality (1.64% vs. 0.74%, P=0.0506). From 2007-2014, the average yearly rate of OUD was 174 cases per 10,000 hospitalizations (174/10,000), almost 3 times higher among CP vs. non-CP (479/10,000 vs. 173/10,000, P<0.001), and it increased from 2007 to 2014 (135/10,000 to 216/10,000, P<0.001). The yearly increase was 2.7 times higher among patients with CP vs. non-CP (29.9/10,000 vs. 11.3/10,000 hospitalizations/year, P<0.001).

Conclusions

CP is associated with higher rates and trends of OUD. Patients with CP at high risk of OUD may benefit from alternate analgesic regimens or surveillance for OUD when they are prescribed opioids.

The Role of Electrical Polarity in Electrospinning and on the Mechanical and Structural Properties of As-Spun Fibers

Electric field strength and polarity in electrospinning processes and their effect on process dynamics and the physical properties of as-spun fibers is studied. Using a solution of the neutral polymer such as poly(methyl methacrylate) (PMMA) we explored the electrospun jet motion issued from a Taylor cone. We focused on the straight jet section up to the incipient stage of the bending instability and on the radius of the disk of the fibers deposited on the collecting electrode. A new correlation formula using dimensionless parameters was found, characterizing the effect of the electric field on the length of the straight jet, L˜E~E˜0.55. This correlation was found to be valid when the spinneret was either negatively or positively charged and the electrode grounded. The fiber deposition radius was found to be independent of the electric field strength and polarity. When the spinneret was negatively charged, L˜E was longer, the as-spun fibers were wider. The positively charged setup resulted in fibers with enhanced mechanical properties and higher crystallinity. This work demonstrates that often-overlooked electrical polarity and field strength parameters influence the dynamics of fiber electrospinning, which is crucial for designing polymer fiber properties and optimizing their collection.

An Analysis of 1-Year Charges for Head and Neck Cancer: Targets for Value-Based Interventions

OBJECTIVE

To identify the dominant clinical factors associated with increased 1-year charges in treating head and neck cancer.

STUDY DESIGN

Retrospective review.

SETTING

Single academic institution.

SUBJECTS AND METHODS

We retrospectively reviewed 1-year charges for 196 consecutive patients with head and neck cancer (HNC) who were treated exclusively at our institution. We analyzed charges by department as well as factors associated with increased charges per multivariable regression.

RESULTS

The mean age was 59.6 years (SD, 14.9). Most of the population was male (64%), white (70%), and commercially insured (46%). The most common primary sites were the oropharynx (25%; 76%, HPV positive), skin (19%), and thyroid (17%). Eighty-three percent of total charges were due to standard-of-care treatment for HNC: surgery ($16 million), radiation therapy ($22 million), or chemotherapy ($11 million). The median total charge per patient was $212,484 (interquartile range, $78,630-$475,823). Multivariable regression demonstrated that the following were associated with increased charges: nasopharynx subsite ($250,929 [95% CI, $93,290-$408,569]; effect size in US dollars, P = .002), advanced stage (American Joint Committee on Cancer, seventh edition; $80,331 [$22,726-$137,936], P = .007), therapeutic surgery ($281,893 [$117,371-$446,415], P = .001), chemotherapy ($183,331 [$125,497-$241,165], P < .001), radiation ($203,397 [$143,454-$263,341], P < .001), surgical complication requiring return to the operating room ($147,247 [$37,240-$257,254], P = .009), emergency department visits ($89,050 [$23,811-$154,289], P = .008), and admissions ($140,894 [$82,895-$198,893], P < .001; constant, -$233,927 [-$410,790 to -$57,064]). The top quartile accrued 55% of the total charges.

CONCLUSION

Radiation, followed by surgery and chemotherapy, were the most expensive components of HNC care. In this analysis, we identified the dominant clinical factors associated with increased charges.

Direct and Indirect Costs of Infectious Conjunctivitis in a Commercially Insured Population in the United States

Purpose

To assess the direct and indirect costs of infectious conjunctivitis and quantify medical costs due to conjunctivitis transmission in families.

Methods

In this retrospective claims analysis from the OptumHealth Care Solutions, Inc. database (1998–2016), beneficiaries with or without at least one diagnosis of infectious conjunctivitis were identified. Direct and indirect costs (in 2016 US$) during the 60 days post conjunctivitis diagnosis (or imputed date for controls) were compared using cost differences in linear regressions. For transmission cost analysis, the total cost of each conjunctivitis episode was the sum of the primary episode (seed patient) and the secondary episode (infected family members) costs. A generalized estimating equation model adjusted for seed patient characteristics was used to assess the impact of number and rate of transmissions on episode cost.

Results

Health care resource utilization and direct costs were significantly higher for patients with conjunctivitis (n=1,002,188) versus controls (n=4,877,210): 1.67 all-cause visits per person per month (PPPM) versus 0.79 visits PPPM, respectively; total mean direct cost of $396.04 PPPM versus $289.63 PPPM, respectively. The cost of medically related absenteeism was $105.42 (95% confidence interval [CI], $104.18–$106.75) higher for patients with conjunctivitis than for controls. Episode cost, without transmission due to seed patient, was $669.43 (95% CI, $654.67–$684.85); it increased with each additional infected family member and with increased infection transmission time between family members.

Conclusion

Conjunctivitis was associated with a notable economic burden in terms of direct medical costs and medically related absenteeism. Family health care costs increased with transmission time and with each family member infected with conjunctivitis.

An Analysis of Current Treatment Trends in Platelet-Rich Plasma Therapy in the Medicare Database

Background:

The use of platelet-rich plasma (PRP) in the Medicare population is not well described.

Purpose:

To investigate the national use of PRP among Medicare beneficiaries, including the incidence and conditions for which it was used in both operative and nonoperative settings, and determine charges to Medicare.

Study Design:

Descriptive epidemiology study.

Methods:

The Medicare Standard Analytical Files within the PearlDiver database were queried for PRP injections by use of Current Procedural Terminology (CPT) code 0232T from 2010 to 2014. A search of every associated International Classification of Diseases, 9th Revision, code and CPT code on the day of the injection was performed, and codes were broadly categorized as shoulder, knee, elbow, hip, and foot/ankle. These categories were then subdivided into 2 groups based on whether the injection was performed at the time of surgery or for a nonoperative condition. The patient data were analyzed by demographics and geographic region. In further analysis, the charges sent to Medicare for PRP injections were stratified by year and musculoskeletal site.

Results:

A total of 3654 PRP injections were coded for and administered during the study period; 57% of recipients were men and 33% were 65 to 69 years of age. We found that 42% of all PRP injections were administered in the southern geographic region. PRP injections were most commonly associated with shoulder diagnoses, followed closely by the foot and ankle and by the knee. The majority of injections given for shoulder conditions were performed at the time of surgery, whereas the majority of knee conditions treated with PRP were associated with nonoperative treatments. Annual charges to Medicare for PRP injections increased 400%, from $500,000 in 2010 to more than $2 million in 2014.

Conclusion:

The use and breadth of PRP therapy have increased substantially in Medicare beneficiaries. Further research is required to obtain a consensus on treatment recommendations for PRP use in this population in addition to strategies to obtain insurance reimbursement.

Ambulatory versus inpatient shoulder arthroplasty: a population-based analysis of trends, outcomes, and charges

Background

The purpose of this study was to evaluate the clinical outcomes and cost of shoulder arthroplasty (SA) performed in ambulatory surgery centers (ASCs) compared with SA performed in hospital-based surgery settings.

Methods

The State Inpatient Databases and the State Ambulatory Surgery Databases were queried for patients undergoing primary or reverse SA between 2010 and 2014 in 5 states in either the inpatient (IP), hospital outpatient department (HOPD), or ASC setting. Outcomes included all-cause readmissions, emergency department visits within the 90-day postoperative period, and charges. Covariates included patient demographic data and procedure details. Risk factors for readmission were calculated using logistic regression analysis.

Results

We identified 795 ASC (2%), 183 HOPD (0.5%), 38,114 (97.5%) SA procedures. The outpatient cohort was overall younger and healthier with a lower percentage of diabetes (14.1% vs. 20.2%), cardiopulmonary disease (11.4% vs. 20.4%), and obesity (10.7% vs. 15.6%). The US state and obesity were factors significantly (P < .0001) associated with readmission. The median IP charge was $62,905 (range, $41,327-$87,881) vs. $37,395 (range, $21,976-$61,775) for combined outpatient cases. When outpatient SA was stratified into ASC and HOPD cases, the median charges were $31,790 for ASC cases vs. $55,990 for HOPD cases (P < .0001). After adjustment for multiple covariates, the charges for combined outpatient SA surgery were 40% lower than those for IP SA surgery (P < .0001).

Conclusion

As the current health care climate shifts toward lower-cost and higher-quality care, this study demonstrates that SAs performed in ASCs have a comparable safety profile to and significant financial advantage over SAs performed in the hospital-based setting.

National estimates of case-mix, mortality, and economic outcomes among inpatient HIV/AIDS mono-infection and hepatitis C co-infection cases in the US

RATIONALE, AIMS, AND OBJECTIVES

To assess inpatient clinical and economic outcomes for AIDS/HIV and Hepatitis C (HCV) co-infection in the United States from 2003 to 2014.

METHOD

This historical cohort study utilized nationally representative hospital discharge data to investigate inpatient mortality, length of stay (LoS), and inflation-adjusted charges among adults (≥18 years). Outcomes were analysed via multivariable generalized linear models according to demographics, hospital and clinical characteristics, and AIDS/HIV or HCV sequelae.

RESULTS

Overall, 17.8% of the 2.75 million estimated AIDS/HIV inpatient cases involved HCV from 2003 to 2014, averaging 48.5 ± 9.0 years of age and 68.0% being male. Advanced sequalae of AIDS and HCV incurred a LoS of 10.3 ± 11.9 days, charges of $88 789 ± 131 787, and a 16.9% mortality. Many cases involved noncompliance, tobacco use disorders, and substance abuse. Although mortality decreased over time, multivariable analyses indicated that poorer outcomes were generally associated with more advanced clinical conditions and AIDS-associated sequalae, although mixed results were observed for specific manifestations of HCV. Rural residence was independently associated with a 3.26 times higher adjusted odds of mortality from 2009 to 2014 for HIV/HCV co-infection (P < 0.001), although not for AIDS/HCV (OR = 1.38, P = 0.166).

CONCLUSION

Given the systemic nature and modifiable risks inherent within coinfection, more proactive screening and intervention appear warranted, particularly within rural areas.

Lightning and charge processes in brown dwarf and exoplanet atmospheres

The study of the composition of brown dwarf atmospheres helped to understand their formation and evolution. Similarly, the study of exoplanet atmospheres is expected to constrain their formation and evolutionary states. We use results from three-dimensional simulations, kinetic cloud formation and kinetic ion-neutral chemistry to investigate ionization processes that will affect their atmosphere chemistry: the dayside of super-hot Jupiters is dominated by atomic hydrogen, and not H₂O. Such planetary atmospheres exhibit a substantial degree of thermal ionization and clouds only form on the nightside where lightning leaves chemical tracers (e.g. HCN) for possibly long enough to be detectable. External radiation may cause exoplanets to be enshrouded in a shell of highly ionized, H₃⁺-forming gas and a weather-driven aurora may emerge. Brown dwarfs enable us to study the role of electron beams for the emergence of an extrasolar, weather system-driven aurora-like chemistry, and the effect of strong magnetic fields on cold atmospheric gases. Electron beams trigger the formation of H₃⁺ in the upper atmosphere of a brown dwarf (e.g. LSR-J1835), which may react with it to form hydronium, H₃O⁺, as a longer lived chemical tracer. Brown dwarfs and super-hot gas giants may be excellent candidates to search for H₃O⁺ as an H₃⁺ product. This article is part of a discussion meeting issue 'Advances in hydrogen molecular ions: H₃⁺, H₅⁺ and beyond'.

Facile Functionalization via Plasma-Enhanced Chemical Vapor Deposition for the Effective Filtration of Oily Aerosol

With the growing concern about the health impacts associated with airborne particles, there is a pressing need to design an effective filter device. The objective of this study is to investigate the effect of plasma-based surface modifications on static charges of electrospun filter media and their resulting filtration performance. Polystyrene (PS) electrospun web (ES) had inherent static charges of ~3.7 kV due to its electric field-driven process, displaying effective filtration performance. When oxygen species were created on the surface by the oxygen plasma process, static charges of electret media decreased, deteriorating the filter performance. When the web surface was fluorinated by the plasma-enhanced chemical vapor deposition (PECVD), the filtration efficiency against oily aerosol significantly increased due to the combined effect of decreased wettability and strong static charges (~-3.9 kV). Solid particles on the charged media formed dendrites as particles were attracted to other layers of particles, building up a pressure drop. The PECVD process is suggested as a facile functionalization method for effective filter design, particularly for capturing oily aerosol.

Experimental and Theoretical Studies on the Adsorption Mechanisms of Uranium (VI) Ions on Chitosan

An experiment on the adsorption of uranium (VI) by chitosan was conducted to investigate the efficiency of chitosan as an adsorbent for U(VI). The adsorption potential of U(VI) by chitosan was investigated with ICP-MS by varying the experimental conditions such as the pH in order to obtain the optimum conditions. Adsorption dependence on the pH was confirmed, and the highest uptake of U(VI) was observed at pH 5. In addition, to scrutinize the experimental results, quantum chemistry calculations were performed. The results, taking into account the experimental conditions, show that the adsorption efficiency increases as the total charge of the adsorbent and adsorbate species decreases if both of them are positively charged. It was also found that a slight change in the adsorption geometric configuration controls the adsorption efficiency.

Predicting Health Care Utilization and Charges Using a Risk Score for Poor Adherence in Pediatric Kidney Transplant Recipients

Pediatric kidney transplant recipients must follow a complicated regimen of timely adherence to immunosuppressant medication, routine blood work, and medical follow-up visits. Failure to adhere to the recommended regimen can result in medical complications and costly treatment. We developed a novel risk score to identify patients at risk for poor adherence behaviors and evaluated whether it would predict future health care utilization and charges. Our risk stratification score combined three simple pass/fail metrics of adherence derived directly from the electronic health record including standard deviation of immunosuppression drug levels, timely laboratory monitoring, and timely clinic visits as indicated by our clinical protocol. Risk for poor adherence was assessed over a three-month period. Linear regression was used to predict subsequent health care charges and utilization. Greater than 75% of patients had some degree of nonadherence risk during the study period, but there were no significant differences found on any outcomes for the overall score. However, when the individual components of the overall risk score were evaluated independently, patients with tacrolimus drug level standard deviation ≥2 (e.g., a marker of poor adherence) had greater health care utilization (e.g., hospitalizations) and increased total charges. Additionally, patients who did not follow up in clinic at least every 4 months had more ED visits and ED-related charges, but fewer hospitalizations. Regular clinic visits and minimizing drug level variation may deter future costly ED visits and hospitalizations.

Evaluation of the cost and length of hospital stays related to the management of an intestinal Clostridium difficile infection

INTRODUCTION

Intestinal Clostridium difficile Infection (CDI) treated in hospitals may concern patients whose reason for admission is CDI (primary diagnosis) or who have acquired CDI during their stay (secondary diagnosis).

OBJECTIVES

The objective of this study is to evaluate the cost for social security and hospitals and the length of hospital stays related to CDIs as the main reason for admission.

METHOD

This study was carried out in 2012 in 13 Belgian hospitals. Cases were selected by using diagnosis recorded in minimum discharge summaries. Pediatric stays are not part of the inclusion criteria (n= 86).

RESULTS

The average length of stay (standard deviation) was 13.53 days (11.95). The average cost (standard deviation) covered by social security/hospitals was €5,019.51 / €6,286.39 (9,638.42/ 6,368.45). 7% of patients were admitted to the Intensive Care Unit during hospitalization, for an average duration (standard deviation) of 8.18 days (2.93). The mortality rate was 8.1%. 19.8% of patients used vancomycin during the stay, 43% were treated with metronidazole only, 12.8% used vancomycin and metronidazole and 24.4% do not received vancomycin or metronidazole. No patients received fidaxomycin.

CONCLUSION

This study made it possible to approach the cost of CDI as the main reason for admission. Such data should allow contributing to optimally assess both the pharmacoeconomic impact of the implementation of prevention strategies and also therapeutic management making use of more expensive medicinal products but associated with decreased risk of recurrence.

Foams Stabilized by β-Lactoglobulin Amyloid Fibrils: Effect of pH

β-Lactoglobulin fibrils could serve as a surface-active component and form adsorption layers at the air/water interface. In this study, the physical parameters related to the surface adsorption, foaming, and surface properties of β-lactoglobulin fibrils as a function of pH (2-8) were investigated. Results showed that an increase of pH from 2 to 5 led to a rise of the viscoelastic modulus of the surface adsorption layer and half-life time (t_1/2) of foams, but it decreased foamability. When the pH was close to its isoelectric point (5.2), fibrils had the lowest electrostatic repulsion and entangled at the air/water interface resulting in a tightly packaged adsorption layer around bubbles to prevent coalescence and coarsening. When the pH (7-8) was higher than the pI of fibrils, the negatively charged β-lactoglobulin fibrils possessed good foamability (∼80%) and high foam stability (t_1/2 ≈ 8 h) simultaneously even at low concentration (1 mg/mL). It demonstrated that β-lactoglobulin fibrils with negative charges presented a good foaming behavior and could be a potential new foaming agent in the food industry.

A theoretical-electron-density databank using a model of real and virtual spherical atoms

A database describing the electron density of common chemical groups using combinations of real and virtual spherical atoms is proposed, as an alternative to the multipolar atom modelling of the molecular charge density. Theoretical structure factors were computed from periodic density functional theory calculations on 38 crystal structures of small molecules and the charge density was subsequently refined using a density model based on real spherical atoms and additional dummy charges on the covalent bonds and on electron lone-pair sites. The electron-density parameters of real and dummy atoms present in a similar chemical environment were averaged on all the molecules studied to build a database of transferable spherical atoms. Compared with the now-popular databases of transferable multipolar parameters, the spherical charge modelling needs fewer parameters to describe the molecular electron density and can be more easily incorporated in molecular modelling software for the computation of electrostatic properties. The construction method of the database is described. In order to analyse to what extent this modelling method can be used to derive meaningful molecular properties, it has been applied to the urea molecule and to biotin/streptavidin, a protein/ligand complex.

Health care institutional charges associated with ambulatory bloodstream infections in pediatric oncology and stem cell transplant patients

BACKGROUND

The impact of ambulatory bloodstream infections (Amb-BSIs) in pediatric oncology and stem cell transplant (PO/SCT) patients is poorly understood, although a large portion of their treatment increasingly occurs in this setting. This study aimed to understand the economic impact and length of stay (LOS) associated with these infections.

PROCEDURE

Charges and LOS were retrospectively collected and analyzed for Amb-BSI events leading to a hospital admission between 2012 and 2013 in a tertiary, university-affiliated hospital. Events were grouped as BSI-MIXED when hospitalizations with care unrelated to the infection-extended LOS by more than 24 hr or as BSI-PURE for all others. Billing codes were used to group charges and main drivers were analyzed.

RESULTS

Seventy-four BSI events were identified in 61 patients. Sixty-nine percent met definition for central line-associated BSI (CLABSI). Median total charge and LOS for an Amb-BSI were $40,852 (interquartile range [IQR] $44,091) and 7 days (IQR 6), respectively. Median charges for BSI-PURE group (N = 62) were $36,611 (IQR $34,785) and $89,935 (IQR $153,263) in the BSI-MIXED (N = 12) group. Median LOS was 6 (IQR 5) days in the BSI-PURE group and 15 (IQR 24) in the BSI-MIXED. Room, pharmacy, and procedure charges accounted for more than 70% of total charges in all groups.

CONCLUSIONS

Amb-BSIs in PO/SCT patients result in significant healthcare charges and unplanned extended hospital admissions. This analysis suggests that efforts aiming at reducing rates of infections could result in substantial system savings, validating the need for increased efforts to prevent Amb-BSIs.

Short term cost of care for the surviving periviable neonate

OBJECTIVE

To determine the hospital cost and distribution of financial charges for the initial hospitalization of the surviving periviable neonate.

STUDY DESIGN

In this retrospective case series, we analyzed medical records and financial data for neonates 23-25 weeks' gestational age in a single tertiary care NICU over 42 months. A detailed breakdown of hospital cost components and charges was determined for all survivors during their initial hospitalization. Statistical significance was determined using the Bonferroni-Sidak method.

RESULTS

Overall survival was 78% in infants born at 23-25 weeks' gestational age. Survival increased and length of stay and hospital costs decreased with increased gestational age (p < 0.05 for all). Hospital charges were distributed as: NICU 56%, respiratory 11%, pharmacy 6%, laboratory 6%, radiology 6%, surgery 1%, neonatology 13% and miscellaneous 1%.

CONCLUSION

Our study describes the hospital cost and distribution of charges for the periviable neonate during the initial hospitalization. These economic data may guide clinicians in quality improvement and cost management.

Peroral endoscopic myotomy achieves similar clinical response but incurs lesser charges compared to robotic heller myotomy

BACKGROUND/AIM

Several uncontrolled studies comparing peroral endoscopic myotomy (POEM) and Heller myotomy have demonstrated equivalent short-term efficacy and safety. However, no data exists rergarding the cost of POEM and how it compares to that of robotic Heller myotomy (RHM). The primary aim of this study was to compare the inpatient charges incurred in patients who underwent POEM or RHM for the treatment of achalasia.

PATIENTS AND METHODS

A retrospective single center review was conducted among 52 consecutive POEM patients (2012-2014) and 52 consecutive RHM patients (2009-2014). All RHM procedures included a Toupet fundoplication and were performed via a transabdominal approach. All POEM procedures were performed by a gastroenterologist in the endoscopy unit. Clinical response was defined by improvement of symptoms and decrease in Eckardt stage to ≤I. All procedural and facility charges were obtained from review of the hospital finance records.

RESULTS

There was no difference between POEM and RHM with regards to age, gender, symptom duration, achalasia subtype, manometry findings, or Eckardt symptom stage. There was no significant difference in the rate of adverse events (19.2% vs 9.6%, P = 0.26) or the length of stay (1.9 vs. 2.3, P = 0.18) between both groups. Clinical response rate of patients in the POEM groups was similar to that in the RHM group (94.3% vs. 88.5%, P = 0.48). POEM incurred significantly less total charges compared to LHM ($14481 vs. $17782, P = 0.02).

CONCLUSIONS

POEM when performed in an endoscopy unit was similar in efficacy and safety to RHM. However, POEM was associated with significant cost savings ($3301/procedure).

Burden of USA hospital charges for traumatic brain injury

OBJECTIVES

This study sought to estimate charges associated with USA hospital visits for traumatic brain injury (TBI), compare charges from 2006-2010 and evaluate factors associated with higher charges.

METHODS

The Nationwide Emergency Department Sample database, 2006-2010, was used to estimate charges for emergency department visits and inpatient hospital stays associated with TBI and trends in charges over time were compared. Multivariable linear regression was used to evaluate factors associated with visit charges.

RESULTS

In 2010, there were $21.4 billion (95% confidence interval (CI) = $17.7-$25.2 billion) in charges for TBI-related admissions, an increase of 22% from 2006. Charges for ED visits resulting in discharge or transfer were $8.2 billion (95% CI = $7.4-$8.9 billion), an increase of 94% from 2006. The proportion of charges for TBI-related visits was disproportionately higher than the proportion of visits for TBI across all years of the study (p < 0.001). Patient age and gender, West region, trauma centre status, non-paediatric hospital designation, metropolitan location and hospital ownership were independently associated with higher charges.

CONCLUSIONS

There was a substantial charge burden from TBI-related hospital visits and charges increased disproportionately to visit volume. There are patient and hospital factors independently associated with higher charges. These findings, as well as methods to reduce the charge burden and charge disparities, deserve further study.

Rehabilitation Charges Associated With Anterior Cruciate Ligament Reconstruction

Background:

Pre- and postoperative rehabilitation are important to the management of patients with anterior cruciate ligament (ACL) reconstruction, but little attention has been given to the costs. This study evaluated the pre- and postoperative rehabilitation charges in patients with ACL reconstruction in the United States.

Hypothesis:

Patients receive preoperative rehabilitation less commonly than postoperative rehabilitation.

Study Design:

Retrospective database study.

Level of Evidence:

Level 4.

Methods:

Using the PearlDiver database, we identified patients undergoing ACL reconstruction from 2007 through 2011 using Current Procedural Terminology codes. The associated rehabilitation charges billed to insurance providers for 90 days preoperatively and 6 months postoperatively were categorized as physical therapy or as durable medical equipment (DME). The charges were examined by year and geographic region and represented as per-patient average charges (PPACs).

Results:

A total of 92,179 patients were identified in the study period. The PPAC for rehabilitation was $241 during the 90-day preoperative period and $1876 for the 6-month postoperative period. Patients averaged 2 preoperative sessions for physical therapy, with 44% of patients receiving preoperative rehabilitation in contrast with an average of 17 postoperative sessions per patient in 93% of patients. Rehabilitation charges were greater postoperatively than preoperatively (P < 0.05). Preoperatively, 24% of patients received a DME, while 35% received a DME postoperatively. Preoperative rehabilitation PPACs were highest in the Northeast, followed by Midwest, South, and West (P < 0.05). There were no significant differences in postoperative rehabilitation PPACs for geographic region (P = 0.43).

Conclusion:

Preoperative rehabilitation charges were lower than postoperative charges. A patient undergoing ACL reconstruction typically received 9 times more sessions of postoperative physical therapy than preoperative.

Clinical Relevance:

This study found that preoperative supervised rehabilitation for patients with ACL reconstruction was infrequent across the United States.

Targeted leukodystrophy diagnosis based on charges and yields for testing

Inherited leukodystrophies are a group of neurological disorders with significant morbidity and mortality. Children and their families can experience lengthy diagnostic odysseys; however, there is no data on the charges related to testing for diagnosis in leukodystrophy patients, compared to approaches using next-generation sequencing (NGS). Our objective was to determine charges related to the determination of diagnosis, and overall yield of diagnostic testing, for leukodystrophy patients. We determined and quantified all inpatient and outpatient lab testing, including brain MRIs, obtained for the purpose of diagnosis, in a retrospective population cohort of children with inherited leukodystrophies. Each patient had average charges of $8,231 (range $543-26,437) for diagnostic testing. Overall charges related to diagnosis for the entire cohort was $526,794. A final etiological diagnosis was determined in 34% of patients. In those in whom a specific diagnosis was determined, average time to diagnosis was 1.4 years. If NGS on the entire cohort had been performed instead, charges would have been ∼$359,600 (at $5,800/patient). Alternatively, a two-tier approach consisting of first, biochemical testing (serum very-long chain fatty acids and leukocyte lysosomal enzyme testing), and then with NGS for remaining undiagnosed patients, would have resulted in total cohort charges of $361,309. We have determined the charges directly associated with diagnostic testing in a population cohort of children with leukodystrophy. We conclude that appropriately incorporating NGS into diagnostic algorithms could lower charges; reduce time to diagnosis; and reduce amount of testing.

The charges for seizures in the pediatric emergency room: a single center study

BACKGROUND

The direct charges for emergency department visits resulting from recurrent seizures are significant, and home intervention with abortive medications can be cost-saving. Over a 1-year period, we evaluated children with seizures who were seen in the emergency department, stabilized, and released. The information is necessary to assess the pharmacoeconomic advantages of at-home interventions for seizure emergencies.

METHODS

We did a retrospective chart review of 90 patients and divided them into febrile versus nonfebrile seizures and existing versus new-onset seizure disorder. The hospital accounting department performed a charge analysis.

RESULTS AND CONCLUSION

The total charges for all 90 patients treated for seizures in the emergency department were $219,945. The minimum was $370, for a patient with no history of febrile seizures. The maximum was $17,126, for a patient with a nonfebrile seizure and a history of seizures. This information allows a comparison with the cost of preventive medications, such as diazepam rectal gel or intranasal midazolam.

Unsustainable hospital charges are incurred in the treatment of Medicare beneficiaries admitted with subarachnoid hemorrhage

INTRODUCTION

Rising medical care expenditures and the unchanging Medicare reimbursements have placed restraints on the health care delivery system.

OBJECTIVE

The goal of this study is to identify the magnitude and determinants of discrepancy between hospitalization charges and Medicare re-imbursement observed in the management of Medicare beneficiaries admitted with aneurysmal subarachnoid hemorrhage in the United States.

METHODS

Patients entered in the Nationwide Inpatient Sample between 2002 and 2010, with a ruptured intracranial aneurysm who underwent either surgical or endovascular treatment were included in the study. Factors associated with higher discrepancy between hospitalization charges and Medicare re-imbursement were identified.

RESULTS

Discrepancies in hospital charges and Medicare reimbursement associated with endovascular and surgical treatment have increased over the decade. The median discrepancy per patient for Medicare patients aged 65 years and older treated surgically or endovascularly for a ruptured aneurysm from 2009 to 2010 was $177,380. The predictors of higher than median discrepancy(charges versus reimbursement), included Hispanic ethnicity (OR 2.1, 95% CI 1.1-3.9, p = 0.02), urinary tract infection (OR 2.0, 95% CI 1.4-2.8, p = <0.001), pneumonia (OR 3.0, 95% CI 1.8-4.8, p = <0.001), deep vein thrombosis (OR 2.5, 95% CI 1.2-5.2, p = 0.02), and pulmonary embolism (OR 18, 95% CI 2.0-169, pp = 0.01).

CONCLUSIONS

There is a growing gap between hospital charges and Medicare reimbursement. If hospitals continue to be reimbursed at significantly lower rates than charges incurred, this current system may be unsustainable due to losses incurred by hospitals.

ABBREVIATIONS

AHRQAgency for Healthcare Research and QualityCMSCenters for Medicare and Medicaid servicesNISNationwide Inpatient Sample.

The relationship of hospital charges and volume to surgical site infection after total hip replacement

The purpose of this study was to analyze the effect of hospital volume and charges on the rate of surgical site infections for total hip replacements (THRs) in New York State (NYS). In NYS, higher volume hospitals have higher charges after THR. The study team analyzed 93,620 hip replacements performed in NYS between 2008 and 2011. Hospital charges increased significantly from $43,713 in 2008 to $50,652 in 2011 (P<.01). Compared with lower volume hospitals, patients who underwent THR at the highest volume hospitals had significantly lower surgical site infection rates (P=.003) and higher total hospital charges (P<.0001). The study team found that in the highest volume hospitals, preventing one surgical site infection was associated with $1.6 million dollars in increased charges.

Cost of morbidities in very low birth weight infants

OBJECTIVE

To determine the association between direct costs for the initial neonatal intensive care unit hospitalization and 4 potentially preventable morbidities in a retrospective cohort of very low birth weight (VLBW) infants (birth weight <1500 g).

STUDY DESIGN

The sample included 425 VLBW infants born alive between July 2005 and June 2009 at Rush University Medical Center. Morbidities included brain injury, necrotizing enterocolitis, bronchopulmonary dysplasia, and late-onset sepsis. Clinical and economic data were retrieved from the institution's system-wide data and cost accounting system. A general linear regression model was fit to determine incremental direct costs associated with each morbidity.

RESULTS

After controlling for birth weight, gestational age, and sociodemographic characteristics, the presence of brain injury was associated with a $12048 (P = .005) increase in direct costs; necrotizing enterocolitis, with a $15 440 (P = .005) increase; bronchopulmonary dysplasia, with a $31565 (P < .001) increase; and late-onset sepsis, with a $10055 (P < .001) increase. The absolute number of morbidities was also associated with significantly higher costs.

CONCLUSION

This study provides collective estimates of the direct costs incurred during neonatal intensive care unit hospitalization for these 4 morbidities in VLBW infants. The incremental costs associated with these morbidities are high, and these data can inform future studies evaluating interventions aimed at preventing or reducing these costly morbidities.

Inpatient burden of gastrointestinal stromal tumors in the United States

The purpose of this study was to determine the inpatient burden among patients with gastrointestinal stromal tumors (GISTs). The study assessed hospitalization rates of GISTs and compared hospital characteristics among patients with and without GISTs. Further, predictors of total charges and mortality among patients with GISTs were identified.The 2009 Healthcare Utilization Project Nationwide Inpatient Sample (HCUP-NIS) database was analyzed for this study. Inpatient burden among patients with GISTs (cases) was compared to that among patients without GISTs or any diagnosis of cancer (controls). Linear regression was used to determine the factors predicting total charges, and logistic regression was used to determine predictors of mortality. Analyses were performed using SAS version 9.2.In 2009, there were 14,562 hospitalizations among patients with GISTs at a rate of 44/100,000 admissions. Hospitalization rates among patients with GISTs varied by patient-, hospital-, and discharge-level characteristics. Patients with GISTs had longer length of stay (LOS), total charges, and mortality rate as compared to the control group. Total charges for hospitalizations among patients with GISTs varied by household income, hospital location and region, LOS, and number of diagnoses on record, respectively. When examining the predictors of mortality, household income, hospital region, and number of diagnoses on record emerged significant.By examining the inpatient burden among patients with GISTs, this study fills a critical gap in this area of research. Future studies could merge medical services claims data with cancer registry data to study in-depth the humanistic and economic burden associated with GISTs.

Self-organization of thin polymer films guided by electrostatic charges on the substrate

The self-organization of thin polymer films into functional patterns is important both scientifically and technologically. Electric fields have been exploited as an efficient and powerful means to induce the destabilization and self-organization of soft materials. Previous attention, however, has mainly focused on externally applied electric fields. It is shown herein that the internal electric field is strong enough to guide the self-organization of thin polymer films as well. Patterns of electrostatic charges with micrometer resolution are first introduced on a dielectric substrate. A thin polymer film is then spin-coated onto the topographically flat substrate. Upon thermal annealing, the thin polymer film destabilizes due to a lateral gradient of electrostatic stress and flows away from the electroneutral regime to the charged area, resembling the patterns of charges on the substrate. Theoretical and numerical modeling based on the electrohydrodynamic instability shows excellent agreement with experimental observations both qualitatively and quantitatively. It is also demonstrated that the interplay between charge-driven instability with spinodal dewetting and Rayleigh instabilities can generate finer and hierarchical polymeric patterns that are completely different from the charge patterns preintroduced on the substrate. This study provides direct evidence that the internal electric field caused by charges on the substrate is strong enough to destabilize thin polymeric films and generate patterns. This study also demonstrates new strategies for bottom-up fabrication of structured functional materials.