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21	Ocular biomechanics of the anterior segment Oehring, Daniela January 2018 (has links) The thesis investigates methods of examining corneal biomechanics using non-contact tonometry and introduces novel techniques to investigate corneal material properties in vivo. A comprehensive systems analysis of the CorvisST (CST) and Ocular Response Analyser (ORA) was performed. Pressure sensors were used to characterisation the airflow produced by the CST and the ORA. Distinct differences were observed between the central airflow pressures between the two devices: the CST pressure was higher and of shorter duration. Scheimpflug high-speed imaging via the CST allowed components of the corneal deformation to be investigated and the development of a 3D deformation matrix (time, depth and spatial resolution) through tracing of the anterior and posterior corneal surface. Measures of whole eye movement (WEM) with CST were found to be robust. WEM demonstrated an asymmetric profile and a correction method was developed to address the corneal deformation matrix for this asymmetry. Novel methods for characterisation of intrinsic material characteristics of the cornea were developed using numerical and graphical analytical procedures. Application of these parameters was tested on enucleated porcine eyes across a wide range of manometry internal ocular pressure (MIOP). The dynamic E-Modulus was found to be most affected by MIOP change. To investigate the in vivo distribution and heterogeneity of the corneal biomechanics, a novel set-up allowed the mapping of corneal biomechanics across the cornea using the CST (central, paracentral, peripheral) and ORA (central, peripheral). Biometric and demographic grouping of subjects allowed detection of discriminating factors between individuals. The results suggest that the in vivo cornea of healthy human adults can be characterised as a viscoelastic, damped system for longitudinal strain and a highly oscillating system for lateral strain. The cornea is approximately homogenous for measures of rigidity and dynamic E-Modulus but other corneal material characteristics (longitudinal and lateral strain, hysteresis, damping and compressibility) demonstrated regional differences. The experimental design employed allowed for strict control of biometric and biomechanical intersubject variables, based on gold-standard techniques as well as newly-developed methods, thereby creating a normative database for future use.
22	Keuhkoahtaumataudin sairaalahoito Suomessa: hoitoajan pituus ja sen yhteys ennusteeseen Kinnunen, T. (Tuija) 03 April 2007 (has links) Abstract The purpose of this work was to determine on the basis of the national hospital discharge register and cause-of-death statistics the extent of the hospital treatment required for chronic obstructive pulmonary disease (COPD) in Finland over the period 1972–2001, i.e. the use made of hospital services, factors affecting the length of stay in hospital and the correlation of length of stay with the prognosis. Different intervals within this period were taken for study according to the themes of the individual papers. The results suggest that the length of stay in hospital varies both geographically and seasonally in Finland, the shortest times being recorded in Northern Finland in summer. The main explanations for this would appear to lie in regional differences in health care resources and treatment practises and in climatic variations. The mean length of stay in hospital in the total material in 1987–1998 was nine days. The longest periods applied to cases with concurrent pneumonia or a cerebrovascular disorder. The duration of treatment for the exacerbation stage of COPD decreased by two days between 1993 and 2001, with the longest periods of treatment observed in the case of elderly women. One week of treatment with current modalities may be regarded as optimal, as this was associated with the longest interval before the next exacerbation, just over six months. About 3% of all emergency admissions ended in death, most commonly on a Friday in winter or spring. Patients admitted at a weekend died within the first 24 hours more frequently than did those admitted on a weekday. The mean duration of treatment and frequency of hospitalization increased towards the terminal stage. About one fourth of the patients had died within a year of the first admission for COPD and about a half within five years. Hospital treatment for COPD intensified in Finland during the 1990s as the numbers of hospital beds decreased. Treatment times became shorter and deaths in hospital during exacerbation became less frequent. It will be necessary from now onwards, however, to anticipate the ageing of the population and to develop treatment modalities to replace hospitalization, in order to reduce the costs accruing from this disease. Early diagnosis and outpatient rehabilitation should be developed, and special attention should be paid to appropriate treatment at the terminal stage. / Tiivistelmä Tutkimuksen tarkoituksena oli selvittää valtakunnallisen hoitoilmoitusrekisterin ja kuolemansyytilaston avulla keuhkoahtaumataudista (KAT) aiheutunutta sairaalahoitoa Suomessa 1972–2001: sairaalapalvelujen käyttöä, hoitojakson pituuteen vaikuttavia tekijöitä sekä hoitoajan yhteyttä ennusteeseen. Lähdeaineistosta valittiin erilaisia ajanjaksoja tutkimusasetelman mukaan. Tulokset viittaavat siihen, että hoitoajan pituus vaihtelee Suomessa maantieteellisesti ja vuodenaikojen mukaan: lyhyin hoitoaika on Pohjois-Suomessa kesällä. Ilmiötä selittänevät pääosin terveydenhuollon resurssien ja hoitokäytäntöjen alueelliset erot sekä ilmasto-olosuhteiden vaihtelu. Vuosina 1987–1998 keskimääräinen hoitoaika koko aineistossa oli yhdeksän vuorokautta. Jos potilaalla oli samanaikaisina sairauksina keuhkokuume tai aivoverenkiertohäiriö, nämä johtivat pisimpiin hoitoaikoihin. KAT:n pahenemisvaiheen hoitoaika lyheni kaksi vuorokautta vuodesta 1993 vuoteen 2001. Iäkkäitten naisten hoitoajat olivat pisimmät. Viikon pituinen hoitoaika nykyisillä hoitomuodoilla oli optimaalinen, sillä tällöin aika seuraavan pahenemisvaiheen hoitojakson alkuun oli pisin: vähän yli puoli vuotta. Kaikista päivystyshoitojaksoista potilaan kuolemaan päättyi kolmisen prosenttia. Yleisimmin tällainen hoitojakso päättyi potilaan kuolemaan perjantaisin ja todennäköisimmin talvella tai keväällä. Viikonloppuna sairaalaan tulleista potilaista kuoli ensimmäisen vuorokauden aikana enemmän kuin arkipäivinä tulleista. Keskimääräinen hoitoaika oli pisin ja sairaalahoito runsainta sairauden loppuvaiheessa kuoleman lähestyessä. Ensimmäisen KAT:n aiheuttaman hoitojakson jälkeen noin neljännes potilaista oli kuollut vuoden sisällä ja viiden vuoden kuluessa noin puolet. Keuhkoahtaumataudin sairaalahoito on tehostunut Suomessa 1990-luvulla sairaansijojen vähentyessä. Hoitoajat ovat lyhentyneet ja pahenemisvaiheiden sairaalakuolleisuus on vähäistä. Väestön ikääntyminen on kuitenkin ennakoitava ja sairaalaa korvaavia hoitomuotoja kehitettävä taudista aiheutuneiden kustannusten hillitsemiseksi. Varhaisdiagnostiikkaa ja avokuntoutusta on kehitettävä ja erityinen huomio kiinnitettävä sairauden loppuvaiheen asianmukaiseen hoitoon. COPD KAT acute exacerbation hospital discharge register hospital mortality length of hospital stay readmission regional variation seasonal variation secondary diagnose hoitoilmoitusrekisteri hoitojakson pituus keuhkoahtaumatauti maantieteellinen vaihtelu pahenemisvaihe sairaalakuolleisuus sivudiagnoosi toistuva hoitojakso vuodenaikojen vaihtelu
23	Disruptive Transformations in Health Care: Technological Innovation and the Acute Care General Hospital Lucas, D. Pulane 24 April 2013 (has links) Advances in medical technology have altered the need for certain types of surgery to be performed in traditional inpatient hospital settings. Less invasive surgical procedures allow a growing number of medical treatments to take place on an outpatient basis. Hospitals face growing competition from ambulatory surgery centers (ASCs). The competitive threats posed by ASCs are important, given that inpatient surgery has been the cornerstone of hospital services for over a century. Additional research is needed to understand how surgical volume shifts between and within acute care general hospitals (ACGHs) and ASCs. This study investigates how medical technology within the hospital industry is changing medical services delivery. The main purposes of this study are to (1) test Clayton M. Christensen’s theory of disruptive innovation in health care, and (2) examine the effects of disruptive innovation on appendectomy, cholecystectomy, and bariatric surgery (ACBS) utilization. Disruptive innovation theory contends that advanced technology combined with innovative business models—located outside of traditional product markets or delivery systems—will produce simplified, quality products and services at lower costs with broader accessibility. Consequently, new markets will emerge, and conventional industry leaders will experience a loss of market share to “non-traditional” new entrants into the marketplace. The underlying assumption of this work is that ASCs (innovative business models) have adopted laparoscopy (innovative technology) and their unification has initiated disruptive innovation within the hospital industry. The disruptive effects have spawned shifts in surgical volumes from open to laparoscopic procedures, from inpatient to ambulatory settings, and from hospitals to ASCs. The research hypothesizes that: (1) there will be larger increases in the percentage of laparoscopic ACBS performed than open ACBS procedures; (2) ambulatory ACBS will experience larger percent increases than inpatient ACBS procedures; and (3) ASCs will experience larger percent increases than ACGHs. The study tracks the utilization of open, laparoscopic, inpatient and ambulatory ACBS. The research questions that guide the inquiry are: 1. How has ACBS utilization changed over this time? 2. Do ACGHs and ASCs differ in the utilization of ACBS? 3. How do states differ in the utilization of ACBS? 4. Do study findings support disruptive innovation theory in the hospital industry? The quantitative study employs a panel design using hospital discharge data from 2004 and 2009. The unit of analysis is the facility. The sampling frame is comprised of ACGHs and ASCs in Florida and Wisconsin. The study employs exploratory and confirmatory data analysis. This work finds that disruptive innovation theory is an effective model for assessing the hospital industry. The model provides a useful framework for analyzing the interplay between ACGHs and ASCs. While study findings did not support the stated hypotheses, the impact of government interventions into the competitive marketplace supports the claims of disruptive innovation theory. Regulations that intervened in the hospital industry facilitated interactions between ASCs and ACGHs, reducing the number of ASCs performing ACBS and altering the trajectory of ACBS volume by shifting surgeries from ASCs to ACGHs. Disruptive Disruptive Innovation Theory Disruptive Transformations Disruptive Innovation Innovation Technology Technological Innovation Medical Innovation Medical Technology Medical Advancement Laparoscopy Laparoscopic Surgery open surgery appendectomy cholecystectomy bariatric surgery weight loss surgery appendectomies cholecystectomies inpatient outpatient ambulatory ambulatory surgery ambulatory surgery center acute care general hospital hospital acute care hospital general hospital health care healthcare hospital industry health care industry Clayton Christensen Clayton M Christensen Michael Porter Harvard Business School Virginia Commonwealth University CMS Health policy public policy public administration organizational theory organization theory Population Ecology Theory Competitive Strategy policy analysis John Kimberly Organization Size Structural Inertia liability of smallness health spending health care cost specialty medical facility open system niche width dynamic outpatient department technology shift surgical setting surgical setting shift medical facility shift substitution threat health system system level analysis Ecological Approach hospital trends ambulatory surgery trends reimbursement rate Medicare CMS coverage decision P J DiMaggio DiMaggio and Powell w w Powell Hannan and Freeman M T Hannan Organizational change minimally invasive surgery less invasive surgery Prospective Payment System Outpatient Prospective Payment System entreprenuerial physician health care organization health care management Roice Luke Carl Ameringer new technology surgical utilization elective surgery Medicare Payment Advisory Commission MedPAC coverage decision trends in surgery abdominal surgery surgical variation physician-owned physician ownership physician autonomy outpatient clinic utilization trends unnecessary surgery Pfeffer Salancik technology diffusion redefining health care interdisciplinary research health care delivery panel design diffusion of hospital technology state variation regional variation local health care market government intervention medical facility health care capacity focused factory advances in health care physician organization relationship hospital competition medical specialization hospital expansion medical arms race integrated care integrated health system J E Wennberg health care transformation reimbursement scheme surgical volume Florida Wisconsin policy making health policy analysis competitive dynamics center of excellence intervening factor service line competition service-line competition surgical reimbursement innovative business model innovative technology environmental influence established firm new market entrant patient safety sophisticated technology Harvard Divinity School Social and Behavioral Sciences

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