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There is a complex interplay between obstructive sleep apnea (OSA) and type 2 diabetes. There are minimal data regarding the effects of treating OSA with positive airway pressure (PAP) therapy on outcomes and health care resource utilization (HCRU) in patients with OSA and type 2 diabetes. We investigated the impact of PAP adherence on HCRU and costs in this population.A retrospective analysis was conducted with a cohort of OSA patient from an US administrative claims dataset linked to objective device data (AirView, ResMed Corp, San Diego, CA). Propensity score matching was used to control for potential imbalance in baseline covariates between PAP adherent and non-adherent patients. Newly diagnosed patients with OSA, aged ≥18 years with type 2 diabetes were included. PAP adherence was defined as meeting Centers for Medicare and Medicaid Services compliance criteria in all eight 90-day periods over 2 years. HCRU was based on the number of all-cause doctor visits, emergency room (ER) visits, inpatient hospitalizations, and PAP equipment and supplies.In Year 1 and 2 of PAP therapy, HCRU was significantly lower in adherent versus non-adherent patients (number/patient for ER visits 0.68±1.47 vs. 0.99±1.91 [Year 1], 0.69±1.43 vs. 0.95±1.89 [Year 2]; for hospitalizations 0.16±0.58 vs. 0.22±0.62 [Year 1], 0.15±0.51 vs. 0.21±0.74 [Year 2]; all p0.001). Changes in estimated total 24-month payments were higher for non-adherent patients ($2282, 95% CI: $1368, $3205).Consistent use of PAP therapy over 2 years was associated with decreased HCRU in patients with OSA and type 2 diabetes, strongly suggesting a role for screening and treating OSA in type 2 diabetes.

Background Obstructive sleep apnea (OSA) is a common comorbidity in patients with heart failure, although current evidence is equivocal regarding the potential benefits of treating OSA with positive airway pressure (PAP) therapy in patients with heart failure. This study assessed the impact of adherence to PAP therapy on health care resource utilization in patients with OSA and heart failure with reduced ejection fraction. Methods and Results Administrative insurance claims data linked with objective PAP therapy use data from patients with OSA and heart failure with reduced ejection fraction were used to determine associations between PAP adherence and a composite outcome of hospitalizations and emergency room visits. One‐year PAP adherence was based on an adapted US Medicare definition. Propensity score methods were used to create groups with similar characteristics across PAP adherence levels. The study cohort included 3182 patients (69.9% male, mean age 59.7 years); 39% were considered adherent to PAP therapy (29% intermediate adherent, 31% nonadherent). One year after PAP initiation, adherent patients had fewer composite visits than matched nonadherent patients, driven by a 24% reduction in emergency room visits for adherent patients. Composite visit costs were lower in adherent versus nonadherent patients ($3500 versus $5879, P =0.031), although total health care costs were not statistically different ($13 028 versus $14 729, P =0.889). Conclusions PAP therapy adherence in patients with OSA with heart failure with reduced ejection fraction was associated with a reduction in health care resource utilization. This suggests that greater emphasis should be placed on diagnosing and effectively treating OSA with PAP in patients with heart failure with reduced ejection fraction.

Rationale: The co-occurrence of obstructive sleep apnea and chronic obstructive pulmonary disease, termed overlap syndrome, has a poor prognosis. However, data on positive airway pressure (PAP) treatments and their impact on outcomes and costs are lacking. Objectives: This retrospective observational study investigated the effects of PAP on health outcomes, resource usage, and costs in patients with overlap syndrome. Methods: Deidentified adjudicated claims data for patients with overlap syndrome in the United States were linked to objectively measured PAP user data. Patients were considered adherent to PAP therapy if they met Centers for Medicare and Medicaid Services criteria for eight 90-day timeframes from device setup through 2-year follow-up. Propensity score matching was used to create comparable groups of adherent and nonadherent patients. Healthcare resource usage was based on the number of doctor visits, all-cause emergency room visits, all-cause hospitalizations, and PAP equipment and supplies, and proxy costs were obtained. Measurements and Main Results: A total of 6,810 patients were included (mean age, 60.8 yr; 56% female); 2,328 were nonadherent. Compared with the year before therapy, there were significant reductions in the number of emergency room visits, hospitalizations, and severe acute exacerbations during 2 years of PAP therapy in patients who were versus were not adherent (all P

STUDY OBJECTIVES: Minimal focus has been placed on variations in health care delivery for obstructive sleep apnea (OSA). This study compared positive airway pressure usage in developing countries (Brazil and Mexico) vs. a developed country (United States) and investigated the impact of a patient engagement tool (myAir; ResMed, San Diego, CA) on adherence. METHODS: Deidentified data from the AirView database (ResMed) for patients receiving positive airway pressure therapy with wirelessly connected Air10 (AirSense and AirCurve) devices in Brazil, Mexico, and the United States were analyzed. Adherence was defined using US Center for Medicare and Medicaid Services (CMS) criteria (usage ≥ 4 h/night on ≥ 70% of nights in the first 90 days). RESULTS: The analysis included 4,181,490 patients (Brazil: 31,672; Mexico 16,934; United States: 4,132,884). CMS adherence over 90 days was slightly lower in Latin America vs. the United States (Brazil: 71.7%; Mexico: 66.4%; United States: 74.0%). Significantly fewer patients were using the patient engagement tool in Brazil (8.1%) and Mexico (2.8%) vs. the United States (26%; both P < .001). Patients registered to use an engagement tool had a higher rate of CMS adherence and were twice as likely to achieve CMS adherence. Average daily usage and days with usage > 4 hours in the first week were the strongest predictors of CMS adherence. Across all countries, > 80% of patients meeting CMS criteria at 3 months were still using positive airway pressure therapy at 1 year, with 1-year adherences rates of > 75%. CONCLUSIONS: Short-term and long-term positive airway pressure adherence rates in Brazil and Mexico were similar to those achieved in the United States. Patients who registered to use an engagement tool consistently had better adherence than those who did not. CITATION: Drager LF, Malhotra A, Yan Y, et al. Adherence with positive airway pressure therapy for obstructive sleep apnea in developing vs developed countries: a big data study. J Clin Sleep Med. 2021;17(4):703–709.

Summary Background Positive airway pressure (PAP) has become a prominent treatment for children with sleep-disordered breathing. However, there are no large-scale studies to clarify whether PAP is well tolerated in children, and which factors are associated with better adherence to PAP therapy. In this study, we aimed to clarify adherence patterns of PAP therapy in a large paediatric population. Methods We did a cross-sectional big-data analysis in children from Oct 1, 2014, to Aug 1, 2018, using existing data derived from PAP devices uploaded nightly in the AirView cloud database. The AirView database is a usage tracking system available to all patients who are assigned PAP therapy, which requires consent from the patient or parent or guardian. All patients older than 4 years and younger than 18 years who used continuous or automated PAP devices were evaluated. Only patients living in the USA and enrolled with a single insurance company were included. If patients were participating in an engagement programme, programme onset must have been within 7 days of therapy onset. Our primary outcome was the proportion of patients who used PAP continuously over 90 days. The primary outcome was assessed in all patients who met the age inclusion criterion and had reliable age data available. Data on missing PAP use were imputed as zero, but data on other metrics were not imputed and excluded from analysis. Findings We used data recorded from Oct 1, 2014, to Aug 1, 2018. Of 40 140 children screened, 36 058 (89·8%) were US residents and 20 553 (90·1%) of them met the eligibility criteria and had accessible data (mean age 13·0 years [SD 3·7]). On the basis of 90 days of monitoring data, 12 699 (61·8%) patients continuously used PAP. Factors significantly associated with adherence included age group, residual apnoea–hypopnoea index, use and onset of patient engagement programmes, PAP pressure, and nightly median PAP mask leak, all over the 90-day study period. Interpretation To our knowledge, our study represents the largest analysis of children using PAP therapy to date. The findings suggest that adherence to PAP therapy is lower than in previous reports from adults. However, numerous actionable factors were associated with improvements in adherence and should be used strategically in clinical decision making to improve PAP adherence in children. Funding ResMed.

Introduction: We have recently reported on big data analysis of early (90 day) and mid-term (one year) compliance and efficacy data from connected CPAP devices. Longitudinal patterns of compliance may provide insights into predicting long-term compliance and into identifying actionable situations for reprogramming adherence trajectories by early interventions. We sought to characterize real world temporal patterns of compliance using novel approaches. Methods: A US based telemonitoring database (AirView, ResMed) was queried for patients starting CPAP/APAP (AirSense 10 device; ResMed) between Aug 2014 and Dec 2016. Longitudinal patterns of compliance in the first 90 days were examined using run-length analysis and frequency analysis. Summary statistics are reported as median and interquartile range (except for age). The study was exempt from IRB oversight. Results: Approximately 1.7 million patients were included in the current analysis. Patient age averaged 55.7 ± 13.5 years. Average daily usage in the first 90 days was 5.6 hours (3.7, 7.0) while usage per session was 6.2 hours (4.8, 7.3). Maximum consecutive days with usage ≥ 4 hours was 20.0 (7.0, 49.0) while the maximum consecutive days with usage > 0 hours was 43.0 (17.0, 84.0). The maximum consecutive days with usage equal to zero was 2.0 (1.0, 5.0). Frequency analysis allowed the identification of specific phenotypes such as on-off behaviour and good compliance with high or low variability (figure 1). Conclusions: Temporal patterns of compliance in large data sets require novel techniques to identify different patient phenotypes. Future research will focus on clustering patterns and linking them to clinical phenotypes as well as predicting long-term adherence and outcomes.

Introduction: Historically ASV devices only allowed a PSmin=3cmH2O, and now they allow PSmin=0. It has been suggested that these differences may influence patient adherence and clinical outcomes through hyperventilation. ASV use has been advocated for many conditions including treatment-emergent CSA, opioid induced CSA, and cardiovascular conditions with preserved EF leading to CSA. We sought to characterise real world use of ASV with a big data approach in clinical practice. Methods: A US based telemonitoring database (AirView, ResMed) was queried for patients starting ASV (AirCurve 10) between 1st Aug 2014 and 1st Nov 2017 to allow at least 1yr of potential follow up. The study was deemed exempt from IRB oversight. Results: Of 32,947 patients on ASV, 78% reached US CMS compliance and of these 78.7% were still using therapy at 1yr. 11.6% had device setting PSmin=0cmH2O. Comparing PSmin=0cmH2O vs >0cmH2O there was no statistical difference in age, usage, leak or AHI. The reported RR and MV were not clinically significantly different compared to published data and also when comparing PSmin=0cmH2O vs >0cmH2O. Adherence to ASV was favourable compared to prior reports. Conclusions: Despite concerns raised in the literature, we observed in real world big data clinically robust adherence to therapy with average RR and modest MV. These data suggest that ASV therapy can be successfully implemented by health care providers.

Introduction: Pressure changes are often implemented during CPAP or APAP therapy. However, there are few data on whether such changes have a clinically relevant impact on respiratory parameters. Aim: To investigate the effects of changing pressure settings during CPAP/APAP on the residual device AHI (AHI_dev). Methods: US telemonitoring device data were analysed. Eligible patients (n = 1,050,394)started APAP/CPAP (AirSense 10 device; ResMed) between Oct 2014 and Dec 2016 and pressure setting changes occurred within the first 90 days of APAP (n=73,458) or CPAP (n=38,060). Important AHI_dev reduction was defined as a decrease from >5/h to Results: Compared with before pressure change, the proportion of patients who had an important reduction in AHI_dev at 30 days after change in CPAP/APAP levels was 18.8% (n=20,929); average AHI_dev decreased from 7.8 to 3.5/h (–56%; p Conclusion: Although pressure changes are often performed when managing positive airway pressure (PAP) therapy, there is only a moderate percentage of patients for whom a change in CPAP/APAP level is associated with clinically meaningful improvement in the AHI. These data imply that pressure adjustments should be one of the many factors that need to be addressed to optimise PAP adherence.

Author(s): Cistulli, Peter A; Armitstead, Jeff; Pepin, Jean-Louis; Woehrle, Holger; Nunez, Carlos M; Benjafield, Adam; Malhotra, Atul

Summary Background There is a scarcity of published data on the global prevalence of obstructive sleep apnoea, a disorder associated with major neurocognitive and cardiovascular sequelae. We used publicly available data and contacted key opinion leaders to estimate the global prevalence of obstructive sleep apnoea. Methods We searched PubMed and Embase to identify published studies reporting the prevalence of obstructive sleep apnoea based on objective testing methods. A conversion algorithm was created for studies that did not use the American Academy of Sleep Medicine (AASM) 2012 scoring criteria to identify obstructive sleep apnoea, allowing determination of an equivalent apnoea-hypopnoea index (AHI) for publications that used different criteria. The presence of symptoms was not specifically analysed because of scarce information about symptoms in the reference studies and population data. Prevalence estimates for obstructive sleep apnoea across studies using different diagnostic criteria were standardised with a newly developed algorithm. Countries without obstructive sleep apnoea prevalence data were matched to a similar country with available prevalence data; population similarity was based on the population body-mass index, race, and geographical proximity. The primary outcome was prevalence of obstructive sleep apnoea based on AASM 2012 diagnostic criteria in individuals aged 30–69 years (as this age group generally had available data in the published studies and related to information from the UN for all countries). Findings Reliable prevalence data for obstructive sleep apnoea were available for 16 countries, from 17 studies. Using AASM 2012 diagnostic criteria and AHI threshold values of five or more events per h and 15 or more events per h, we estimated that 936 million (95% CI 903–970) adults aged 30–69 years (men and women) have mild to severe obstructive sleep apnoea and 425 million (399–450) adults aged 30–69 years have moderate to severe obstructive sleep apnoea globally. The number of affected individuals was highest in China, followed by the USA, Brazil, and India. Interpretation To our knowledge, this is the first study to report global prevalence of obstructive sleep apnoea; with almost 1 billion people affected, and with prevalence exceeding 50% in some countries, effective diagnostic and treatment strategies are needed to minimise the negative health impacts and to maximise cost-effectiveness. Funding ResMed.

There are currently few data on the impact of mask resupply on longer-term adherence to positive airway pressure (PAP) therapy. This retrospective analysis investigated the effects of mask/mask cushion resupply on the adherence to PAP versus no resupply. Deidentified patient billing data for PAP supply items were merged with telemonitoring data from Cloud-connected AirSense 10/AirCurve 10 devices via AirViewTM (ResMed). Eligible patients started PAP between 1 July 2014 and 17 June 2016, had ≥360 days of PAP device data, and achieved initial U.S. Medicare adherence criteria. Patients who received a resupply of mask systems/cushions (resupply group) were propensity-score-matched with those not receiving any mask/cushion resupply (control group). A total of 100,370 patients were included. From days 91 to 360, the mean device usage was 5.6 and 4.5 h/night in the resupply and control groups, respectively (p &lt, 0.0001). The proportion of patients with a mean device usage ≥4 h/night was significantly higher in the resupply group versus the control group (77% vs. 59%, p &lt, 0.0001). The therapy termination rate was significantly lower in the resupply group versus the control group (14.7% vs. 31.9%, 0.0001), there was a trend toward lower therapy termination rates as the number of resupplies increased. The replacement of mask interface components was associated with better longer-term adherence to PAP therapy versus no resupply.

Rationale: OSA is a major clinical problem due to its high prevalence and devastating complications. At present, the European prevalence of OSA is unclear. Limited epidemiological studies have been done and the majority of the European population has not had a reliable estimate of disease. We sought to estimate the European prevalence of OSA using existing data from epidemiological studies. Methods: We contacted the majority of authors of the important analyses following a review of the literature. For countries where no measurement had been made, we used publically available data to obtain estimates of age, gender, race and BMI. We developed an algorithm to match countries without prevalence estimates with countries from which OSA epidemiological studies existed. The situation was complicated given the variable age of the existing studies, the differences in technology used (eg. nasal pressure vs thermistor), the changing scoring criteria (eg. AASM 1999 vs 2007 v. 2012) and other factors. Results: Among the 50 countries in Europe there was population, gender, race and BMI data available for 39. We estimated a European OSA prevalence of approximately 175 million (44.0%) people based on the AASM 2012 criteria using a somewhat conservative approach to our estimates. When focusing on patients with moderate to severe OSA (AHI≥15) we estimate roughly 90 million (22.7%) patients in Europe. Conclusion: This large burden of disease has not been widely appreciated and speaks to the need to leverage new technology to diagnose and treat this specific population. Further efforts with advocacy are also required for patients, providers and policy makers to develop strategies regarding how best to address.

The U.S. Environmental Protection Agency and Research Triangle Institute, working under a cooperative agreement, have investigated source reduction technologies available to the gravure and flexographic segments of the printing industry. This research focused on investigating ink feed systems and pollution prevention technologies that can be used with these systems. Ink feed systems move ink from an ink sump to a printing cylinder and are located at each printing station on a press. These systems are a component of the overall ink handling process used in printing facilities. Other ink handling processes include ink mixing operations, the transport of the ink to the press, and the actual printing operation where ink is transferred from the printing cylinder to the substrate. This paper provides background information on flexography and gravure. In addition, the paper describes the ink handling process (including traditional ink feed systems) used in these industry segments. Finally, the paper details several innovative ink feed systems that are available and describes the benefits of using these technologies.

IntroductionFor patients with obstructive sleep apnoea (OSA) who are initially non-compliant with continuous (automatic) positive airway pressure (CPAP/APAP) therapy, a bilevel PAP (Spont/VAuto) therapy transition pathway is available to improve therapy adherence. The aim of this retrospective study was to compare PAP therapy usage data of patients with non-compliant OSA (ncOSA) on CPAP/APAP who were switched to bilevel PAP.MethodsA PAP telemonitoring database was queried between 1 January 2015 and 31 July 2016 for eligible patients started on CPAP/APAP and non-CMS (United States Center for Medicare and Medicaid Services) compliant and switched to bilevel PAP within 90 days of starting CPAP/APAP therapy. PAP therapy data on all patients were compared before switch (CPAP/APAP) and after switch (VAuto/Spont).ResultsOf the 1496 patients with ncOSA identified, 30.3% used CPAP, 62.3% APAP, and 7.4% both APAP and CPAP before switching to a bilevel mode. 47.8% patients switched to Spont mode and 52.2% to VAuto mode. PAP usage significantly improved by 0.9 h/day (pConclusionThis shows for the first time that there may be potential benefit from switching from CPAP/APAP to bilevel PAP for patients struggling with PAP adherence.

The perioperative environment is one of the most technologically advanced areas of the modern healthcare enterprise. From the anesthesia machine to the physiologic monitors in the PACU, the use of computer technology now collects and displays thousands of data points per hour, in thousands of operating rooms across the world. Increasing numbers of modern operating rooms (ORs) are also now equipped with computerized anesthesia information management systems (AIMS), which capture the data from the monitors and anesthesia machines, interface with existing hospital information systems (HIS), and allow the anesthesia staff to construct an electronic version of the perioperative patient record. Most of the AIMS do more than simply recreate a handwritten record on a computer screen or a paper printout; they also store these data in some form of an electronic database. The management of a modern anesthesia service is complicated by many of the same challenges that face healthcare as a whole. The increased scrutiny of medical errors, personnel shortages, cost and billing pressures, privacy and security issues, and medical legal concerns can impact all facets of anesthesia practice. The benefits of documentation automation with an AIMS, and the analysis of the data that are collected, can help address these challenges. Unfortunately, many of the anesthesia departments that have implemented AIMS use them

Styrene is the monomer used as a cross-linking agent in the majority of fiber-reinforced plastics manufacturing processes. Its evaporation is undesirable from environmental, health and safety, and economic perspectives. The effect of a proprietary Fluid Impingement Technology™ (FIT™) nozzle, developed by Magnum Industries, on styrene emissions was evaluated and compared to other conventional application equipment — conventional spray guns and flow coaters (operated at both low and high pressure). The FIT™ nozzle produced less styrene emissions during both gel coating and resin testing, with significant emissions reduction occurring during the application process.

The solution rheology of different generations of hyperbranched polyesters in N-methyl-2-pyrrolidinone (NMP) solvent was examined in this study. The solutions exhibited Newtonian behavior over a wide range of polyester concentrations. Also, the relative viscosities of poly(amidoamine) (PAMAM) dendrimers in ethylenediamine were compared with those of the hyperbranched polyesters in NMP. Both types of dendritic polymers have relative viscosities that are exponential functions of their molar fraction in solution. The slopes of these relative viscosity curves show a linear relationship with respect to the generation number. PAMAM dendrimers have the greater slopes for each generation, reflecting their relatively larger intrinsic viscosity values.

The rheological properties of different generations of hyperbranched polyesters in 1-methyl-2-pyrrolidinone solvent and their blends with a poly(2-hydroxyethyl methacrylate) are examined in this study. All the hyperbranched polyester solutions exhibit Newtonian behavior, with steady shear viscosities independent of shear rate. This indicates the absence of physical entanglements in these systems. In addition, solution viscosities are found to be only slightly affected by the different generations of the hyperbranched polymer. The polyesters have very small intrinsic viscosities, and their hydrodynamic radius scales as Rh ∼ M0.39, suggesting a less packed structure than dendrimers. All generations of the hyperbranched polyesters also show comparable apparent activation energies of flow over the temperature range studied. Replacing linear polymers with hyperbranched polymers causes large reductions in the blend viscosities. This behavior can be attributed to the decrease in both the number of physical entan...

This objective of this paper is to demonstrate that NMP is a viable pollution prevention alternative to methylene chloride. Marine Corps Logistics Base (MCLB), Albany, GA, USA was the host site for the demonstration. MCLB's primary function is maintenance of military ground support vehicles, electronic equipment, and small arms. These maintenance processes require the use of methylene chloride to depaint or strip metal parts. A full scale demonstration of NMP was performed at the host site, which included equipment retrofits and material substitution. A cost analysis, using standard US EPA costing methods, was performed and emissions were estimated based on material usage. Results show that, based on the success measures and criteria established by MCLB, NMP is a satisfactory pollution prevention alternative to methylene chloride.

Styrene is a designated hazardous air pollutant, per the 1990 Clean Air Act Amendments. It is also a tropospheric ozone precursor. Fiber-reinforced plastics (FRP) fabrication is the primary source of anthropogenic styrene emissions in the United States. This paper describes an empirical model designed to predict styrene emission factors for selected FRP fabrication processes. The model highlights 10 relevant parameters impacting styrene emission factors for FRP processes, and helps identify future areas of FRP pollution prevention (P2) research. In most cases, the number of these parameters with greatest impact on styrene emission factors can be limited to four or five. Seven different emission studies were evaluated and used as model inputs.

Pollution prevention (P2) options to reduce styrene emissions, such as new materials and application equipment, are commercially available to the operators of open molding processes. However, information is lacking on the emissions reduction that these options can achieve. To meet this need, the U.S. Environmental Protection Agency's (EPA) Air Pollution Prevention and Control Division, working in collaboration with Research Triangle Institute, measured styrene emissions for several of these P2 options. In addition, the emission factors calculated from these test results were compared with the existing EPA emission factors for gel coat sprayup and resin applications. Results show that styrene emissions can be reduced by up to 52% by using controlled spraying (i.e., reducing overspray), low-styrene and styrene-suppressed materials, and nonatomizing application equipment. Also, calculated emission factors were 1.6-2.5 times greater than the mid-range EPA emission factors for the corresponding gel coat and resin application. These results indicate that facilities using existing EPA emission factors to estimate emissions in open molding processes are likely to underestimate actual emissions. Facilities should investigate the applicability and feasibility of these P2 options to reduce their styrene emissions.

Hybrid blends of poly(amidoamine) PAMAM dendrimers with two linear high polymers, poly(vinyl chloride), PVC, and poly(vinyl acetate), PVAc, are reported. The interaction between the blend components was studied using dynamic mechanical analysis, xenon nuclear magnetic resonance (NMR) spectroscopy, and tensile property measurements. The data suggest a much higher degree of interaction between components of PVAc-containing blends compared to those containing PVC. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 2111–2117, 1998

On October 16, 1846, medical science, and the world, learned that the pain caused by surgical operations had been conquered. Mankind now possessed a potion so pow­ erful, that a soul entranced by its fumes paid no mind to the horror that was sur­ gery in that age. That first demonstration taught another, more subtle lesson to those who would pursue this newly created medi­ cal art: to harness the properties of this potent liquor, to deliberately poison a person's breath and to alter the conscious­ ness of that living being would require a clever instrument of some precision. From that day forward, anesthetists have em­ ployed a variety of devices to deliver the gases and vapors of anesthesia to their pa­ tients. The modern anesthesia machine is a collection of components whose inven­ tion and refinement parallel the history of anesthesia practice and whose lineage can be traced back to that October morning in Boston one hundred and fifty years ago. The demonstration was set to begin this morning, bu t William Thomas Green Morton was in danger of being late. He was working feverishly on an instrument with which to administer the secret compound, so that he could claim as his own the break­ through that had eluded medicine for cen­ turies. He remembered vividly the failed attempt by his one-time partnel� Horace Wells, to make public a similar discovery, and vowed not to suffer the same humilia­ tion. As the time grew near, he continued to assemble what was to become the first working anesthesia inhaler in history. The appointed hour had come and passed, and now IS minutes late, Dr. Morton arrived in the operating theater j ust in time to stop the surgeon from cutting skin. It was the last-minute work on the inhaler that made him late, but it was that same inhaler that helped him announce to the world that a new era of medical practice had begun. Morton's ether inhaler was a two-necked glass globe that was stuffed with a few small sponges soaked with ether. It was a simple draw-over vaporizer, with a short non­ rebreathing mouthpiece, and an inlet for fresh atmospheric gas flow. This basic de­ sign was widely copied and modified, as the accounts of his amazing discovery spread across the globe. William Morton not only introduced the concept of surgical anesthesia, but also created the prede­ cessor of all anesthesia "machines" to fol­ low. The journey from this modest begin­ ning to the state-of-the-art computerized anesthesia workstations of today was com­ pleted in three stages, the first of which was the era of inhalers.

Dibenzylidene sorbitol (DBS) is capable of gelling a variety of organic solvents and polymeric materials by forming a rigid, 3-D hydrogen-bonded network. In this work, two poly(siloxane)/poly(propylene oxide) segmented copolymers of equal composition and molecular weight, but different architectures (endblocked vs. pendant), as well as a pure poly(propylene oxide), have been gelled with DBS. We have investigated the dynamic rheological properties of these gels to ascertain the effect of copolymer architecture, PDMS comonomer and DBS concentration on network formation.

The Air and Energy Engineering Research Laboratory (AEERL) of the US Environmental Protection Agency (EPA) is investigating the barriers to the use of radiation-cured technology in the coated and laminated substrate manufacturing industry. This paper presents information gathered from radiation-curable coating and equipment suppliers as well as technical publications. The focus of this project was to investigate the use of radiation-curable coatings as an alternative to conventional solvent-based coatings used in the coated and laminated substrate manufacturing industry. Data obtained included material inputs, equipment, output characteristics, emissions, and waste. Information was gathered to compare process and cost impacts to evaluate the technical, educational, and economic barriers to radiation-curable coatings for this industry. Pollution prevention/source reduction research opportunities were also identified.

This paper discusses the work and results to date leading to the demonstration of the corona destruction process at pilot scale. The research effort in corona destruction of volatile organic compounds (VOCs) and air toxics has shown significant promise for providing a valuable contribution to critical U.S. Environmental Protection Agency and national goals of reducing the health effects associated with exposures to hazardous air pollutants. The corona destruction technology could be especially useful in future years in helping industry meet the residual risk requirements of the Clean Air Act Amendments of 1990. Since 1988, EPA has conducted research in the area of corona destruction of VOCs and air toxics. EPA's interest in corona destruction of molecular species started with modeling of a point-plane reactor for destroying toxic organic compounds. EPA's goal is to develop a technology capable of controlling low concentration streams at low capital and operating costs. The purpose of this work is to develop an industrial scale corona reactor capable of efficiently and cost-effectively destroying VOCs and air toxics at ambient temperature and pressure. Results show that corona destruction is a promising control technology for many VOC-contaminated air streams, especially at low concentrations. Cost comparisons are presented for corona destruction and conventional control devices, carbon adsorption, catalytic incineration and thermal incineration.

Catalytic oxidation is an air pollution control technique in which volatile organic compounds (VOCs) and vapor-phase air toxics in an air emission stream are oxidized with the help of a catalyst Design of catalytic systems for control of point source emissions is based on stream-specific characteristics and desired control efficiency. This paper discusses the key emission stream characteristics and VOC characteristics that affect the applicability of catalytic oxidation. The application of catalytic oxidation technology to four types of air emission sources is discussed: (1) groundwater stripping operations; (2) graphic arts facilities; (3) flexographic printing plants; and (4) latex monomer production. The characteristics of each of these emissions are discussed along with the catalytic technology used to control these emissions.