La chirurgie est le traitement principal du cancer colorectal (CCR). Une durée d'hospitalisation prolongée peut augmenter le risque de complications et d'inactivité physique, entraînant un déclin de la fonction physique. L'objectif de cette étude est de déterminer si la celle-ci peut prédire l’hospitalisation prolongée chez les patients atteints de CCR. Un total de 459 patients provenant de 7 cohortes a été analysé. Une régression logistique a été utilisée pour déterminer le risque d'hospitalisation prolongée (>3 jours) et une courbe ROC a été tracée pour établir la sensibilité/spécificité. Les variables sélectionnées comprenaient l'âge, le sexe, l'IMC, la présence de comorbidités, le statut ASA, le site tumoral, l'approche chirurgicale, la force de préhension, le test Timed-Up and Go, le test assis-debout de 30 secondes, le test de flexion des coudes de 30 secondes, le test de marche de 6 minutes (6MWT), le questionnaire CHAMPS et le SF-36. Les résultats démontrent que les patients atteints d'une tumeur rectale ont un risque 2,7 fois plus élevé d'appartenir au groupe d'hospitalisation prolongée que ceux atteints d'une tumeur du côlon (O.R. 2,7 ; C.I. 1,3-5,7, p=0,01). Pour chaque augmentation de 20 mètres dans le 6MWT, il y a une diminution de 9% du risque d'être dans le groupe d'hospitalisation prolongée (C.I. 1.03-1.17, p=0.00). Un seuil de 431 m peut prédire 70% des patients dans le groupe d'hospitalisation prolongée (AUC 0,71, C.I. 0,63-0,78, p=0,00). L'utilisation du 6MWT comme outil de dépistage de l'hospitalisation prolongée devrait être intégrée dans le parcours chirurgical préopératoire. / Surgery is the primary treatment for colorectal cancer. A prolonged Length of Stay (pLOS) can increase risk of complications and physical inactivity, leading to a decline in physical function. While promising results were seen from preoperative exercise training and post-operative functional recovery, the predictive potential of preoperative physical function has not yet been investigated. The objective of this study is to determine if preoperative physical function can predict pLOS in patients with for colorectal cancer. A total of 459 patients from 7 cohorts were analyzed. Logistic regression was used to determine risk of pLOS (>3 days), and ROC curve was plotted to establish sensitivity/specificity. Selected variables included age, sex, BMI, comorbidity, ASA status, tumor site, surgical approach, handgrip strength, Timed-Up and Go, 30-second Sit-to-Stand, 30-second Arm Curl Test, 6-Minute-Walking Test (6MWT), CHAMPS Physical Activity Questionnaire for Older Adult and 36-Item Short Form Survey. The results showed that patients with rectal tumor are 2.7x more at risk to be in the pLOS group compared to those with colon tumor (O.R. 2.7; C.I. 1.3-5.7, p=0.01). For every increment of 20 meters in 6MWT, there is a decreased risk of 9% of being in pLOS group (C.I. 1.03-1.17, p=0.00). A cut-off of 431m can predict 70% of patients in pLOS group (AUC 0.71 C.I 0.63-0.78, p=0.00). Tumor site (rectal) and 6MWT were significant predictors of pLOS. Using the 6MWT as a screening tool for pLOS with cut-off of 431 m should be implemented in the preoperative surgical pathway.

No description available.

[pt] O tempo de permanência (LoS) é uma das métricas mais utilizadas para avaliar o uso de recursos em Unidades de Terapia Intensiva (UTI). Esta tese propõe uma metodologia estruturada baseada em dados para abordar três principais demandas de gestores de UTI. Primeiramente, será proposto um modelo de predição individual do LoS em UTI, que pode ser utilizado para o planejamento dos recursos necessários. Em segundo lugar, tem-se como objetivo desenvolver um modelo para predizer o risco de permanência prolongada, o que auxilia na identificação deste tipo de paciente e assim uma ação mais rápida de intervenção no mesmo. Finalmente, será proposto uma medida de eficiência ajustada por case-mix capaz de realizar análises comparativas de benchmark entre UTIs. Os objetivos específicos são: (i) realizar uma revisão da literatura dos fatores que predizem o LoS em UTI; (ii) propor uma metodologia data-driven para predizer o LoS individual do paciente na UTI e o seu risco de longa permanência; e (iii) aplicar essa metodologia no contexto de um grande conjunto de UTIs de diferentes tipos de hospitais. Os resultados da revisão da literatura apresentaram os principais fatores de risco que devem ser considerados em modelos de predição. Em relação ao modelo preditivo, a metodologia proposta foi aplicada e validada em um conjunto de dados de 109 UTIs de 38 diferentes hospitais brasileiros. Este conjunto continha um total de 99.492 internações de 01 de janeiro a 31 de dezembro de 2019. Os modelos preditivos construídos usando a metodologia proposta apresentaram resultados precisos comparados com a literatura. Estes modelos propostos têm o potencial de melhorar o planejamento de recursos e identificar precocemente pacientes com permanência prolongada para direcionar ações de melhoria. Além disso, foi utilizado o modelo de predição proposto para construir uma medida não tendenciosa para benchmarking de UTIs, que também foi validada no conjunto de dados estudado. Portanto, esta tese propôs um guia estruturado baseado em dados para gerar predições para o tempo de permanência em UTI ajustadas ao contexto em que se deseja avaliar. / [en] The length of stay (LoS) in Intensive Care Units (ICU) is one of the most used metrics for resource use. This thesis proposes a structured datadriven methodology to approach three main demands of ICU managers. First, we propose a model to predict the individual ICU length of stay, which can be used to plan the number of beds and staff required. Second, we develop a model to predict the risk of prolonged stay, which helps identifying prolonged stay patients to drive quality improvement actions. Finally, we build a case-mix-adjusted efficiency measure (SLOSR) capable of performing non-biased benchmarking analyses between ICUs. To achieve these objectives, we divided the thesis into the following specific goals: (i) to perform a literature review and meta-analysis of factors that predict patient s LoS in ICUs; (ii) to propose a data-driven methodology to predict the numeric ICU LoS and the risk of prolonged stay; and (iii) to apply this methodology in the context of a big set of ICUs from mixed-type hospitals. The literature review results presented the main risk factors that should be considered in future prediction models. Regarding the predictive model, we applied and validated our proposed methodology to a dataset of 109 ICUs from 38 different Brazilian hospitals. The included dataset contained a total of 99,492 independent admissions from January 01 to December 31, 2019. The predictive models to numeric ICU LoS and to the risk of prolonged stay built using our data-driven methodology presented accurate results compared to the literature. The proposed models have the potential to improve the planning of resources and early identifying prolonged stay patients to drive quality improvement actions. Moreover, we used our prediction model to build a non-biased measure for ICU benchmarking, which was also validated in our dataset. Therefore, this thesis proposed a structured data-driven guide to generating predictions to ICU LoS adjusted to the specific environment analyzed.

The treatment of spontaneous pneumothorax in the civilian population can be influenced by the age of the patient and the presence of associated pulmonary disease. The medical records of 130 patients who presented with 168 occurrences of SP were reviewed during an 11-year period (1973 to 1984). Follow-up was from a minimum of 30 months to 13 years (mean 6.3 years). The therapeutic options included observation alone (40 occurrences), thoracentesis (6 occurrences), chest tube thoracostomy (102 occurrences), and thoracotomy (20 occurrences). Treatment of SP should be prompt with the objective of complete re-expansion of the lung and prevention of recurrent pneumothorax. This should be accomplished by the use of chest tube thoracostomy with early addition of thoracotomy as necessary. Selected use of thoracentesis can be effective. The use of observation alone can be dangerous and is associated with a higher recurrence rate.

M. Tech. (Department of Tourism and Hospitality Management, Faculty of Human Sciences) Vaal University of Technology. / Tourism is regarded as a global phenomenon in the 21st Century and is the world’s largest and fastest growing industry. Many countries globally look at tourism as a key driver for economic growth and rescue to their economic slumber (Brida, Lanzilotta, Moreno & Santiñaque 2018:62). In South Africa, tourism contributed immensely to total employment and economic activity in the country and the government sees this industry as a great resource, the country’s strategy for expansion and a possible vehicle to take South Africa into a new economic trajectory. The National Department of Tourism developed the National Tourism Sector Strategy (NTSS 2016-2026) to facilitate the growth of this industry. As a result, direct tourism performance is measured on an ongoing basis against the goals set for South Africa of which two of the performance measures are length of stay and direct spend (NTSS 2019). These two are important because if visitors stay for longer periods at a destination, their spending increases as they partake in more tourism activities and pay for accommodation. This in turn increases the value attached to tourism as an engine for economic growth (SA Tourism 2007:59). Tourists’ spending and length of stay are therefore very important variables in the tourism industry as they contribute immensely to the economic value of tourism to specific destinations (Wong, Fong, & Law, 2016:958; Wang, Fong, Law & Fang 2018:472; Montañoa, Rossellób & Sansób 2019:112). Length of stay and average spend per day by tourists are fluctuating for South Africa as a tourism destination (SAT 2009-2018). The growth of both these variables has also been small over a period of ten years. These fluctuations and slow growth exert pressure on the tourism industry (SAT 2005-2018) and therefore annually form part of the strategic objectives of the National Department of Tourism (NTSS 2019). An in-depth analysis of these two variables is lacking and understanding the factors influencing these two variables within a South African context is of paramount importance to improving the economic value of tourism to the country. Although the factors influencing the two variables have been widely researched, these cannot be stereotyped to all destinations as they are destination specific (Barros & Machado 2010:693; Gemara & Correiab 2018:56) and these have not been analysed in the context of South Africa as a tourism destination. Though fluctuating patterns and slow growth on tourists’ length of stay and spending in South Africa is evident and is a cause of concern, the real problem here is lack of in-depth information on factors which influence these two key variables from a South African perspective. Even though South African Tourism have placed length of stay and spending of tourists as key strategic variables that need to be closely monitored and improved it needs action from the South African context. Once these factors are known, only then can South African Tourism be able to condition them positively for the benefit of the country’s economy. This research therefore sought to explore the factors influencing the stay duration and spending behaviour of international air tourists to South Africa and how these factors can be developed to increase tourists’ length of stay and spending in South Africa. Hence the aim of this research was to identify and analyse factors that influence length of stay and spending behaviour of international tourists reaching South Africa by air and in both cases, attention was given to the intrinsic and extrinsic contributing factors. Literature was reviewed on tourists’ travel behaviour by means of an in-depth discussion of travel motivations in general and travel motivations to South Africa specifically, tourists’ decision-making process, type of holiday decisions tourists makes, and the factors that influence these tourists’ decisions. The composition of the total tourism product was also analysed as this has an influence on tourists’ travel behaviour. This was followed by a comprehensive analysis of literature concerning tourists’ spending behaviour and visitors’ length of stay, which form the pith of this study. The analysis focused on the definition of concepts such as tourists’ length of stay and spending behaviour, the importance of length of stay and spending behaviour of tourists in tourism, how tourism spending is measured, how tourism expenditure data is gathered, what constitutes tourism spending/expenditure and lastly the factors which influence tourists’ length of stay and spending behaviour. A quantitative paradigm in the form of a sample survey was used in conducting this research. This research follows a cross-sectional design (exploratory and descriptive in nature at the same time) which involves the collection of data on more than one case and at a single point in time. The target population of this study comprised international tourists who visited South Africa by air. These visitors were accessed at one of the top tourist attractions in Cape Town (one of the most popular cities for international tourists) namely Table Mountain Cable Way. Table Mountain was selected as a data collection hub as it enjoys the lion’s share of South Africa’s international tourist arrivals. According to the Table Mountain Aerial Cableway Company (TMACC2014:11), Table Mountain was named Africa’s leading tourist attraction in the World Travel Awards 2014 which makes it possible to pull many international tourists to the country of South Africa. Guided by previous similar studies, the sample size for this study was predetermined at 800 respondents of which 720 were completed without error signifying a response rate of 90%. A non-probability sampling technique namely convenience sampling was chosen for this survey as no list was available on who would be visiting the Table Mountain Arial Cable Way. The 800 international tourists were therefore purposively (only international visitors) and conveniently recruited depending on their willingness to participate in the research project; thus, a non-probability sampling technique was followed. Through the researcher distributing the questionnaire in person and using own judgement, a diverse range of nationalities, age groups and gender was included in the sample for it to be a close representation of all the visitors to South Africa as well as of the phenomenon under investigation. The questionnaire was designed and used to obtain detailed data on travel motivations, spending patterns and length of stay of the international air tourist market to South Africa. The questionnaire was designed from previous studies related to the above key variables and this added to the content validity of the questionnaire. A pre-test study was conducted by means of 10 survey questionnaires administered to academic experts at a University who had travelled abroad, and this added to the face validity of the questionnaire. The Statistical Package for the Social Sciences (SPSS) version 23.0 for Windows was used to analyse the data and data gathered was presented by means of frequency tables and analytically described, subjected to exploratory factor analysis, one-way analysis of variances (ANOVA), t-tests, and Spearman’s rank order correlation analysis to establish the relationships between variables. Based on the empirical findings of this research project it is concluded that more males than females participated in this research and on average the age of the participants is 41 years, mostly married people and mainly staying in hotels and lodges. A variety of nationalities participated in this research but most of the respondents were from USA, UK followed by a huge margin from Germany, Netherlands and Australia, a profile which matches that of typical visitors to South Africa and were holders of a degree or diploma, followed by those with a postgraduate qualification with the majority being professionals followed by those in managerial positions. Most of the respondents to the study were first-time visitors to South Africa, travelling in a group of 3 or less people, and the average number of people in the travel group was 4 people and the average number of previous visits to South Africa was 1.68 times. Many of the respondents to this study travelled to South Africa mainly for holiday/leisure mostly to enjoy the natural attractions of South Africa since they placed high importance on appreciation of natural resources, enjoyment of beautiful scenery and sightseeing of tourist spots as important travel motivators. Most of the respondents to this study stayed on average 16.42 days which is higher than the annual average length of stay of international tourists. This information is very important from a marketing perspective as it helps in the profiling of tourists, targeting, tourism product development and positioning. Of importance as well is the fact that that the bigger the travel group the higher their spending will be. The most important aspects directly and significantly influencing length of stay were time constraints, the location of South Africa and financial constraints. It can be concluded that length of stay, availability of time to shop and respondents’ experience as a tourist directly and significantly contributes to visitor spending while interaction with the locals does not. The main travel motivations of international tourists to South Africa were Relaxation and Novelty, Social motivations, Cultural and heritage motivations, Personal Motivations and Destination motivations, of which Relaxation and Novelty and Cultural and Heritage motivations were rated high as travel motivations of tourists to South Africa. The main factors influencing length of stay of the respondents to this study were Personal experience, Access attributes, Destination attributes and Personal constraints. Of these factors, personal constraints and destination attributes ranked the highest as influencers of tourists’ length of stay. The respondents’ length of stay was least influenced by access attributes. The main factors influencing tourist spending patterns as determined by the factor analysis were: “Access and opportunity”, “Time availability” and “External influences”. Tourists’ spending was to a larger extent influenced by time availability followed by access and opportunity but least affected by external influences. The recommendations to increase length of stay and spending of inbound air tourists to South Africa made in this study are specific to South Africa as they were derived from a deep exploration of factors that influence air tourists’ length of stay and spending behaviour to South Africa. If South African Tourism, tourism industry associations and business owners implement these recommendations, this will improve both stay duration and spending of inbound air tourists to South Africa which has been fluctuating and showing slow growth. The recommendations most importantly add to literature that was lacking from a South African perspective on how length of stay and spending can be positively influenced for inbound air tourists to South Africa. The recommendations are as follows: South African Tourism, various industry associations (FEDHASA, ASATA, GHASA, RASA, SATSA), tour operators and travel agents, individual tourism and hospitality business companies that offer tourism products and services to inbound air tourists should take into consideration that length of stay is inhibited by personal constraints. It is thus important to offer value for money to the tourists. Continuous creative marketing strategies should be employed to attract long staying tourists to this country. South African Tourism, tourism business owners and industry associations should utilise new approaches and strategies that provides information about diverse range of attractions, spending opportunities and facilitate easy access as these are important to tourists who stay longer. Tourists’ personal experiences have a significant influence on tourists’ decisions to stay for longer periods hence South African Tourism and respective industry associations should offer thorough training to tourism and hospitality product/service providers and employees to enhance quality interaction with the visitors as this has a significant influence on the tourists’ decisions to stay longer in South Africa. Tourists that have been to South Africa before were influenced by personal experiences to stay for longer periods while the older and higher educated tourists were less influenced by the length of stay factors owing to their experience and confidence of what they want from a holiday in South Africa. South African Tourism, industry associations and tourism business owners should therefore target repeat visitors and the old, educated tourist market as they tend to stay for longer periods thus adding to the economic returns through their prolonged spending. Tourists that travel in larger groups are influenced by personal constraints, namely time and money; hence creating opportunities for value packages by tourism business owners in conjunction with wholesale and retail travel companies will ensure that this market stays longer in South Africa. Since destination attributes have proven to significantly influence length of stay of international tourists to South Africa, South Africa Tourism needs to create awareness on tourism opportunities that are not fully realised. This will increase tourists’ knowledge of the wide variety of activities and attractions to see in South Africa; hence they will budget long enough time to enjoy these products. Since spending patterns of tourists are influenced by time availability, if tourists stay longer, they will have enough time to shop and to experience destination products and services; hence their spending will rise. It is important to improve the environment related to Access and opportunity, Time availability and External influences as these factors influence how much tourists spend in the destination visited. The most important aspect to give attention to in order increase tourists’ spending is time availability. Opportunities should be created for tourists to spend money, which should be communicated on various platforms. South African Businesses that offer shopping opportunities (especially in shopping malls) should extend shopping hours late in the evening to allow tourists time to shop but safety and security should be geared up. Most of the tours do not always offer ample time for shopping and this should be communicated to the tour operators as it will also assist the local economy to grow.

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No description available.

Thesis (MMed)--Stellenbosch University, 2014. / ENGLISH ABSTRACT: BACKGROUND Post anesthesia discharge criteria scoring systems have been used successfully to aid discharge from the post anesthetic care unit (PACU) for over 40 years. They do not replace, but rather act in conjunction with good clinical judgment, and provide concise, standardized documentation of a patient’s readiness for discharge. 1,2,3,4,5 In order to improve patient safety, provide clear documentation and to aid future audit, a discharge criteria scoring system was developed for use in our PACU (Addendum A). It is a modification of the Aldrete Scoring System and the modified Post Anesthetic Discharge Scoring System (PADSS) proposed by Chung.1 There is a steadily increasing patient burden on the existing medical infrastructure in South Africa. Tygerberg Academic Hospital is no exception, and because of the high demand on our theatre services, optimal efficiency is essential. We speculated that our discharge criteria scoring system might increase the efficiency of our PACU when compared to the traditional time based system. The more healthy patients, undergoing minor procedures, could potentially spend less time in PACU, allowing the nurses to focus on problem cases. Increasing the speed of transit might also help prevent delays in theatre due to lack of bed space in PACU. Our primary endpoint was to compare the duration of time spent by patients in the PACU at Tygerberg Academic Hospital, from the moment they are admitted, to the time they are discharged to the ward, before and after the introduction of a discharge criteria scoring system. While planning the audit, one of the factors that staff identified as contributing to delayed discharge from PACU, was the time it took for the wards to collect their patients. A secondary objective, therefore, was to assess the amount of time that elapsed between calling the ward to collect the patient, and the patient leaving PACU. METHODS AND MATERIALS Prior to commencing the audit, approval was obtained from the Human Research Ethics Committee of the Faculty of Health Sciences of the University of Stellenbosch and Tygerberg Academic Hospital. The Audit, its purpose and possible benefits, was discussed with representatives of the nurses working in PACU, and written consent was obtained from those who would be involved in the data collection (Addendum B). Audit forms (Addendum C), collection boxes, and posters reminding staff to participate in the audit were prepared. Our first audit was performed over approximately a week in August 2012. During this period, the traditional time-based discharge system was still in operation. Data was captured from 327 patients. Audit forms were placed in a collection box, which was cleared daily by the primary investigator. The discharge criteria scoring system was introduced to the PACU staff in January 2013. The nurses were trained in its use, and a one month period was allowed for all involved to become accustomed to the new system. A second audit was performed in February 2013, again over a week, during which we gathered data from 313 patients. RESULTS The median value of the time spent by patients in the PACU decreased from 1 hour 25 minutes, to 1 hour 15 minutes, after introduction of the discharge criteria scoring system. This was statistically significant (p-value = 0.003). The median time between calling the ward to collect a patient, and the patient leaving recovery, was 15 minutes. CONCLUSION The main finding of the study was that the introduction of a discharge criteria scoring system decreased the median duration of time spent by patients in the post anesthetic care unit at Tygerberg Academic Hospital. / AFRIKAANSE OPSOMMING: AGTERGROND Puntestelsels as ontslag kriteria na narkose, word vir die afgelope 40 jaar suksesvol gebruik as maatstaf om pasiënte uit die herstelkamer te ontslaan. Hierdie kriteria vervang nie goeie kliniese oordeel nie, maar is ’n addisionele hulpmiddel om te bepaal of die pasiënt gereed is vir ontslag en om noukeurige, gestandardiseerde dokumentasie te verseker. 1,2,3,4,5 'n Nuwe puntestelsel vir ontslag is vir die herstelkamer van Tygerberg Akademiese Hospitaal ontwikkel om pasiëntesorg en dokumentasie te verbeter, asook om ouditering in die toekoms te vergemaklik (Addendum A). Hiervoor is die Aldrete Scoring System en die gemodifiseerde PADSS, voorgestel deur Chung, aangepas. 1 Die bestaande mediese infrastruktuur in Suid-Afrika beleef tans ‘n geleidelike toename in die getal pasiënte. Tygerberg Akademiese Hospitaal is geen uitsondering nie en as gevolg van die hoë aanvraag na ons teaterdienste, is uiterste doeltreffendheid noodsaaklik. Ons vermoede was dat hierdie aangepaste puntestelsel doeltreffendheid in die herstelkamer sou verbeter in vergelyking met die meer tradisionele tyd-gebaseerde sisteem. Gesonde pasiënte wat kleiner prosedures ondergaan, sal waarskynlik na ’n korter periode ontslaan kan word wat die verpleegpersoneel in staat sal stel om meer aandag aan probleem gevalle te gee. Bespoediging van die pasiëntvloei behoort onnodige vertragings van teatergevalle weens 'n tekort aan beddens in die herstelkamer, te beperk. Die primêre doel van die studie was om te bepaal of die gebruik van die aangepaste puntestelsel as ontslag kriteria in Tygerberg Akademiese Hospitaal, die tydperk wat die pasiënt in die herstelkamer deurbring, verkort. Die herstelkamer verpleegsters het beweer dat die saal personeel ‘n lang tyd gevat het om hulle pasiente in herstelkamer te kom haal. Vervolgens is 'n sekondêre doelwit ingesluit om die tydperk te bepaal vandat die saalpersoneel in kennis gestel word, totdat die pasiënt die herstelkamer verlaat. METODE Goedkeuring is verkry van die Menslike Navorsing en Etiese Komitee van die Gesondheidswetenskap Fakulteit van die Universiteit van Stellenbosch en Tygerberg Akademiese Hospitaal voor die aanvang van die studie. Die studie, asook die doel en moontlike voordele daarvan is vooraf bepsreek met verteenwoordigers van die herstelkamer verpleegpersoneel en skriftelike toestemming is verkry van al die deelnemers wat betrokke sou wees by die data versameling (Addendum B). Oudit vorms (Addendum C), versamelhouers en inligtingsplakkate vir die betrokke personeel is voorberei. Die aanvanklike oudit is in Augustus 2012 oor 'n periode van ongeveer een week uitgevoer. Tydens hierdie oudit is die tradisionele tydgebaseerde sisteem gebruik. Inligting van 327 pasiёnte is versamel. Die oudit vorms is in die versamelbokse geplaas en is daagliks deur die primêre navorser verwyder. Die aangepaste puntestelsel as ontslag kriteria, is in Januarie 2013 in die herstelkamer geïmplementeer. Die verpleegpersoneel het opleiding ontvang waarna die aangepaste puntestelsel vir een maand gebruik is om te verseker dat die personeel vertroud is daarmee. In Februarie 2013, is ‘n tweede oudit oor ‘n tydperk van een week uitgevoer, waartydens inligting van 313 pasiёnte versamel is. RESULTATE Na die implementering van die aangepaste puntestelsel as ontslag kriteria, het die mediane tyd wat pasiënte in die herstelkamer deurbring afgeneem van 1 uur en 25 minute tot 1 uur en 15 minute. Hierdie afname is statities betekenisvol (p-waarde = 0.003) Die mediane tyd vandat die saal in kennis gestel is totdat die pasiënt die herstelkamer verlaat, was 15 minute. GEVOLGTREKKING Die hoof bevinding van die studie is dat die mediane tydperk wat die pasiënte in die herstelkamer deurbring verminder is deur die implementering van die aangepaste puntestelsel as ontslag kriteria in Tygerberg Akademiese Hospitaal.

Thesis (PhD)--Stellenbosch University, 2014. / ENGLISH ABSTRACT: When estimating the covariance matrices of two or more populations, the covariance matrices are often assumed to be either equal or completely unrelated. The common principal components (CPC) model provides an alternative which is situated between these two extreme assumptions: The assumption is made that the population covariance matrices share the same set of eigenvectors, but have di erent sets of eigenvalues. An important question in the application of the CPC model is to determine whether it is appropriate for the data under consideration. Flury (1988) proposed two methods, based on likelihood estimation, to address this question. However, the assumption of multivariate normality is untenable for many real data sets, making the application of these parametric methods questionable. A number of non-parametric methods, based on bootstrap replications of eigenvectors, is proposed to select an appropriate common eigenvector model for two population covariance matrices. Using simulation experiments, it is shown that the proposed selection methods outperform the existing parametric selection methods. If appropriate, the CPC model can provide covariance matrix estimators that are less biased than when assuming equality of the covariance matrices, and of which the elements have smaller standard errors than the elements of the ordinary unbiased covariance matrix estimators. A regularised covariance matrix estimator under the CPC model is proposed, and Monte Carlo simulation results show that it provides more accurate estimates of the population covariance matrices than the competing covariance matrix estimators. Covariance matrix estimation forms an integral part of many multivariate statistical methods. Applications of the CPC model in discriminant analysis, biplots and regression analysis are investigated. It is shown that, in cases where the CPC model is appropriate, CPC discriminant analysis provides signi cantly smaller misclassi cation error rates than both ordinary quadratic discriminant analysis and linear discriminant analysis. A framework for the comparison of di erent types of biplots for data with distinct groups is developed, and CPC biplots constructed from common eigenvectors are compared to other types of principal component biplots using this framework. A subset of data from the Vermont Oxford Network (VON), of infants admitted to participating neonatal intensive care units in South Africa and Namibia during 2009, is analysed using the CPC model. It is shown that the proposed non-parametric methodology o ers an improvement over the known parametric methods in the analysis of this data set which originated from a non-normally distributed multivariate population. CPC regression is compared to principal component regression and partial least squares regression in the tting of models to predict neonatal mortality and length of stay for infants in the VON data set. The tted regression models, using readily available day-of-admission data, can be used by medical sta and hospital administrators to counsel parents and improve the allocation of medical care resources. Predicted values from these models can also be used in benchmarking exercises to assess the performance of neonatal intensive care units in the Southern African context, as part of larger quality improvement programmes. / AFRIKAANSE OPSOMMING: Wanneer die kovariansiematrikse van twee of meer populasies beraam word, word dikwels aanvaar dat die kovariansiematrikse of gelyk, of heeltemal onverwant is. Die gemeenskaplike hoofkomponente (GHK) model verskaf 'n alternatief wat tussen hierdie twee ekstreme aannames gele e is: Die aanname word gemaak dat die populasie kovariansiematrikse dieselfde versameling eievektore deel, maar verskillende versamelings eiewaardes het. 'n Belangrike vraag in die toepassing van die GHK model is om te bepaal of dit geskik is vir die data wat beskou word. Flury (1988) het twee metodes, gebaseer op aanneemlikheidsberaming, voorgestel om hierdie vraag aan te spreek. Die aanname van meerveranderlike normaliteit is egter ongeldig vir baie werklike datastelle, wat die toepassing van hierdie metodes bevraagteken. 'n Aantal nie-parametriese metodes, gebaseer op skoenlus-herhalings van eievektore, word voorgestel om 'n geskikte gemeenskaplike eievektor model te kies vir twee populasie kovariansiematrikse. Met die gebruik van simulasie eksperimente word aangetoon dat die voorgestelde seleksiemetodes beter vaar as die bestaande parametriese seleksiemetodes. Indien toepaslik, kan die GHK model kovariansiematriks beramers verskaf wat minder sydig is as wanneer aanvaar word dat die kovariansiematrikse gelyk is, en waarvan die elemente kleiner standaardfoute het as die elemente van die gewone onsydige kovariansiematriks beramers. 'n Geregulariseerde kovariansiematriks beramer onder die GHK model word voorgestel, en Monte Carlo simulasie resultate toon dat dit meer akkurate beramings van die populasie kovariansiematrikse verskaf as ander mededingende kovariansiematriks beramers. Kovariansiematriks beraming vorm 'n integrale deel van baie meerveranderlike statistiese metodes. Toepassings van die GHK model in diskriminantanalise, bi-stippings en regressie-analise word ondersoek. Daar word aangetoon dat, in gevalle waar die GHK model toepaslik is, GHK diskriminantanalise betekenisvol kleiner misklassi kasie foutkoerse lewer as beide gewone kwadratiese diskriminantanalise en line^ere diskriminantanalise. 'n Raamwerk vir die vergelyking van verskillende tipes bi-stippings vir data met verskeie groepe word ontwikkel, en word gebruik om GHK bi-stippings gekonstrueer vanaf gemeenskaplike eievektore met ander tipe hoofkomponent bi-stippings te vergelyk. 'n Deelversameling van data vanaf die Vermont Oxford Network (VON), van babas opgeneem in deelnemende neonatale intensiewe sorg eenhede in Suid-Afrika en Namibi e gedurende 2009, word met behulp van die GHK model ontleed. Daar word getoon dat die voorgestelde nie-parametriese metodiek 'n verbetering op die bekende parametriese metodes bied in die ontleding van hierdie datastel wat afkomstig is uit 'n nie-normaal verdeelde meerveranderlike populasie. GHK regressie word vergelyk met hoofkomponent regressie en parsi ele kleinste kwadrate regressie in die passing van modelle om neonatale mortaliteit en lengte van verblyf te voorspel vir babas in die VON datastel. Die gepasde regressiemodelle, wat maklik bekombare dag-van-toelating data gebruik, kan deur mediese personeel en hospitaaladministrateurs gebruik word om ouers te adviseer en die toewysing van mediese sorg hulpbronne te verbeter. Voorspelde waardes vanaf hierdie modelle kan ook gebruik word in normwaarde oefeninge om die prestasie van neonatale intensiewe sorg eenhede in die Suider-Afrikaanse konteks, as deel van groter gehalteverbeteringprogramme, te evalueer.

<p>Uvod: Akutni apendicitis predstavlja jedno od najče&scaron;ćih abdominalnih hirur&scaron;kih oboljenja u dečjem uzrastu. Lečenje je operativno, primenom otvorene hirurgije ili primenom minimalno invazivne hirurgije tj. laparoskopske apendektomije. Iako je laparoskopska apendektomija, zbog svojih prednosti, stekla popularnost kod mnogih hirurga, jo&scaron; uvek nije &scaron;iroko primenjena metoda na na&scaron;im prostorima. Prednost izvođenja laparoskopske apendektomije u odnosu na otvorenu metodu u dečjem uzrastu je i dalje nedovoljno definisana i predmet je mnogih istraživanja. Cilj istraživanja je da se utvrdi da li je dužina hospitalizacije kod dece operisane laparoskopski zbog akutnog apendicitisa kraća u odnosu na otvorenu metodu, kao i da se utvrdi da li postoji razlika u pojavi postoperativnih komplikacija između ove dve hirur&scaron;ke metode. Pored toga, cilj istraživanja je i da se utvrdi uticaj obe metode lečenja na kvalitet života i brzinu uspostavljanja svakodnevnih aktivnosti. Metodologija: Na Klinici za dečju hirurgiju, Instituta za zdravstvenu za&scaron;titu dece i omladine Vojvodine, sprovedena je prospektivna, kontrolisana randomizirana studija, u trajanju od deset meseci, u koju su bili uključeni svi pacijenti sa akutnim apendicitisom, kod kojih je planirana apendektomija, a čiji roditelji su dali pismeni pristanak za uče&scaron;će u istraživanju. Svi ispitanici su podeljeni u dve osnovne grupe u odnosu na operativnu tehniku: otvorena i laparoskopska apendektomija. Potom su svi ispitanici podeljeni u tri podgrupe, u zavisnosti od stepena upaljenosti crvuljka (negativni, nekomplikovani i komplikovani apendicitis). Svaki ispitanik je imao svoj individualni protokol istraživanja gde su preoperativno zabeleženi: uzrast, pol, simptomi (vrsta i dužina), fizikalni pregled, laboratorijske analize (broj leukocita, hematokrit), ultrazvučni nalaz, procena op&scaron;teg stanja, udružena oboljenja, vreme od prijema do operacije, preoperativna antibiotska terapija. Intraoperativno je analizirano: vrsta hirurgije, nalaz na apendiksu, prisustvo peritonitisa, udružena patologija, dužina operacije i trajanje pneumoperitoneuma (kod laparoskopske apendektomije), patohistolo&scaron;ki nalaz apendiksa, bakteriolo&scaron;ki bris abdomena. Postoperativno su analizirani: antibiotska terapija (vrsta i dužina), započinjanje peroralnog unosa, utvrđivanje postoperativnog bola, febrilnost, uspostavljanje peristaltike creva, izgled rane, postoperativne komplikacije (infekcija rane, intraabdominalni apscesi, ileus) i dužina hospitalizacije. Posebno su analizirani kvalitet života pacijenata nakon operacije pomoću modifikovanog upitnika SF 10 za dečji uzrast, kao i uspostavljanje svakodnevnih aktivnosti pomoću Activity Assessment Scale (AAS), modifikovane za dečji uzrast, nakon svakog postoperativnog dana, prvih sedam dana, nakon mesec dana, tri i &scaron;est meseci od operacije. Svi pacijenti su operisani u uslovima op&scaron;te anestezije. Klasična, otvorena apendektomija je vr&scaron;ena kroz naizmenični rez u desnoj ilijačnoj jami. Po otvaranju peritoneuma, cekum je izvučen i načinjena je klasična apendektomija. Laparoskopska apendektomija je vr&scaron;ena kroz tri 5 mm porta. Pneumoperitoneum je kreiran otvorenom metodom po Hasson-u, kroz infraumbilikalnu inciziju, a preostala dva porta su postavljena desno i levo ilijačno. Mezenteriolum je zbrinut pomoću ultrazvučnih makaza. Postavljene su intrakorporalne ligature i apendiks je odstranjen kroz desni port. Rezultati: Tokom perioda od deset meseci operisano je ukupno 125 pacijenata uzrasta od 2 do 18 godina, zbog akutnog apendicitisa. Laparoskopskom tehnikom je operisano 60 pacijenata (48%), a otvorenom metodom 61 (48,8%). Kod 4 pacijenta je načinjena konverzija, tj. promena operativne tehnike iz laparoskopske u otvorenu metodu. Nije bilo statistički značajne razlike između terapijskih grupa u odnosu na stepen upaljenosti apendiksa, vrstu i dužinu trajanja simptoma, u dijagnostičkim procedurama, kao ni u vremenu proteklom od prijema u bolnicu do operacije. Srednje operativno vreme je iznosilo 65 minuta (25-185 min) za laparoskopsku grupu i 45,49 minuta (25-90 min) za otvorene apendektomije (razlika je statistički značajna, p&lt;0,001). Crevna peristaltika, kao i započinjanje peroralnog unosa, se statistički značajno ranije uspostavljaju u grupi laparoskopsko operisanih. U grupi laparoskopskih apendektomija, postoperativne komplikacije (infekcija rana i formiranje intraabdominalnih apscesa) su se javile kod 8,33% ispitanika (5/60), a u otvorenoj grupi kod 4.91%, (3/61), &scaron;to nije bilo statistički značajno (c2 = 0,152; df = 1; p = 0,696). Dužina hospitalizacije kod dece operisane laparoskopski je iznosila 5,95 } 1,21 dana, a otvoreno 6,43 } 1,09 dana, &scaron;to je statistički značajna razlika (t = -2,206; p = 0,029). Rezultati Man-Vitnijevog U testa su pokazali statistički značajno bolji ukupni skor svakodnevnih aktivnosti za grupu laparoskopskih apendektomija (Z = -7,608; p = 0,000). U svim ispitivanim indikatorima kvaliteta života, deca laparoskopske grupe su imala veći skor. Deca sa akutnim apendicitisom operisana laparoskopski značajno ranije postižu visok stepen kvaliteta života (t = 2,407; p = 0,018). Zaključak: Prednost minimalno invazivne hirurgije u terapiji akutnog apendicitisa u dečjem uzrastu ogleda se u bržem uspostavljanju ponovnog funkcionisanja gastrointestinalnog trakta, kraćoj hospitalizaciji, a samim tim i bržem sveukupnom oporavku, vraćanju svakodnevnim aktivnostima i dobrom kvalitetu života. Postoperativne komplikacije se podjednako javljaju, kako kod otvorene, tako i kod laparoskopske operativne tehnike.</p> / <p>Introduction: Acute appendicitis is one of the most common abdominal surgical diseases in children. Operative treatment means open surgery or minimally invasive surgery (laparoscopic appendectomy). Although laparoscopic appendectomy, gained popularity among many surgeons, it is still not widely accepted in our region. The advantage of laparoscopic appendectomy compared to the open method in children is still not sufficiently defined and is the subject of further research. The aim of the research was to determine whether the length of hospital stay after laparoscopic surgery in children with acute appendicitis is shorter compared to the open method, as well as to determine whether there is a difference in the occurrence of postoperative complications after these two operative techniques. In addition, the aim of the research was to determine the effect of both methods of treatment on quality of life and everyday functioning. Methodology: This prospective, randomized controlled study was performed at the Clinic for Pediatric Surgery, Institute of Children and Youth Healthcare of Vojvodina, during a period of ten months. All patients with acute appendicitis, whose parents have given written consent, were included in research. All patients were divided into two basic groups, in relation to the surgical technique: open or laparoscopic appendectomy. Then, all of them were divided into three groups, depending on the degree of appendicitis (negative, uncomplicated and complicated appendicitis). Each participant had their own individual research protocol where we recorded preoperatively: age, sex, symptoms (type and length), physical examination, laboratory tests (white blood cell count, hematocrit), ultrasound finding, general state (ASA classification), associated diseases, time from admission to surgery, preoperative antibiotic therapy. During the operation we analyzed: type of surgery, degree of the appendicitis, the presence of peritonitis, associated pathology, length of surgery and duration of pneumoperitoneum (in laparoscopic appendectomy), hystopathologic findings of the appendix, a bacteriology. Postoperatively we analyzed: antibiotic therapy (type and length), oral intake, postoperative pain, fever, establishing peristalsis, the appearance of postoperative complications (wound infections, intra-abdominal abscesses, ileus) and length of hospitalization. Especially, we analyzed the quality of life of patients after surgery using the modified questionnaire SF 10 for children; and the establishment of daily activities using Activity Assessment Scale (AAS), modified for children; after each postoperative day, the first seven days, one month, three and six months after surgery. All patients were operated under general anesthesia. Open appendectomy was performed through incision in the right iliac fossa. Peritoneum was opened, the cecum was pulled out and classic appendectomy was made. Laparoscopic appendectomy is performed through three 5 mm ports. Pneumoperitoneum was created by the Hasson techique, through the infraumbilical incision, and the remaining two ports are set at right and left iliac region. Mezenteriolum was ligated by ultrasonic scissors. After putting intracorporal ligature, appendix was removed through the right port. Results: Over a period of ten months we operated 125 patients , aged 2 to 18 years, due to acute appendicitis. Laparoscopic technique was performed in 60 patients (48%), and the open method in 61 (48,8%). In 4 patients the conversion was made (operative technique changed from laparoscopic to open method). There were no statistically significant differences between the treatment groups with respect to the degree of appendix inflammation, the type and duration of symptoms, the diagnostic procedures, as well as the time from hospital admission to the surgery. Medium operative time was 65 minutes (25-185 min.) for laparoscopic group and 45,49 minutes (25-90 min.) for open appendectomy (the difference is statistically significant, p&lt;0,001). Intestinal peristalsis, as well as the initiation of oral intake was significantly sooner established in the laparoscopic group. Postoperative complications (wound infections and intra-abdominal abscess formation In laparoscopic appendectomy) occurred after laparoscopy in 8,33% of patients (5/60), and in the open group in 4,91% (3/61), which was not statistically significant (c2 = 0,152, df = 1; p = 0,696). Length of hospital stay in children operated by laparoscopy was 5,95 } 1,21 days and by open technique 6,43 } 1,09 days, which is significantly longer (t = -2,206; p = 0,029). Results of the Mann-Whitney U test showed significantly better overall record of daily activities for a group of laparoscopic appendectomy (Z = -7,608; p = 0,000). In all tested indicators of quality of life, children from laparoscopic group had a higher score. Children with acute appendicitis treated by laparoscopic surgery achieved a high level of quality of life, significantly earlier (t = 2,407; p = 0,018). Conclusion: The advantage of minimally invasive surgery in the treatment of acute appendicitis in children is reflected in the faster re-establishment of functioning of the gastrointestinal tract, shorter hospitalization and therefore, a faster overall recovery, resuming normal activities and a good quality of life. Postoperative complications occur equally in both, open as well as in laparoscopic operative techniques.</p>