This study was aimed at determining whether the digital volume pulse waveform using the Pulse Sensor can be used to extract features related to arterial compliance. The Pulse Sensor, a low-cost photoplethysmograph, measures green light reflection in the finger and generates output, which is indicative of blood flow and can be read by the low-cost Arduino UNO™. The Pulse Sensor code was modified to increase the sampling frequency and to capture the data in a file, which is subsequently used for waveform analysis using programs written in the R system. Waveforms were obtained using the Pulse Sensor during two 30-s periods of seated rest, in each of 44 participants, who were between the ages of 20 and 80 years. For each cardiac cycle, the first four derivatives of the waveform were calculated and low-pass filtered by convolution before every differentiation step. The program was written to extract 19 features from the pulse waveform and its derivatives. These features were selected from those that have been reported to relate to the physiopathology of hemodynamics. Results indicate that subtle features of the pulse waveform can be calculated from the fourth derivative. Feature misidentification occurred in cases of saturation or low voltage and resulted in outliers; therefore, trimmed means of the features were calculated by automatically discarding the outliers. There was a high efficiency of extraction for most features. Significant relationships were found between several of the features and age, and systolic, diastolic, and mean arterial blood pressure, suggesting that these features might be employed to predict arterial compliance. Further improvements in experimental design could lead to a more detailed evaluation of the Pulse Sensor with respect to its capability to predict factors related to arterial compliance.

Denna artikel presenterar en Learning Study som innehåller tre forskningslektioner.Syftet med studien var att analysera på vilket sätt variationsmönster inverkar på enelevgrupps lärande och förståelse för vad som påverkar blodomloppet. Studiensdesign baserades på Variationsteorin och undersökningsgruppen utgjordes av 45elever i årskurs sex. Resultatet visade att alla elever utvecklade sina kunskaper omvad som påverkar blodomloppet. Genom att åskådliggöra blodcirkulationen som ettsammanbundet system och hur en väska transporteras i ett helt system gentemot ettsystem med hål i fick eleverna se att oavsett var i systemet brottet är påverkas alla delarna. / This Learning Study consisting three research lessons with the aim to analyse inwhat way patterns of variation have impact on pupils’ learning about what affectsblood circulation. Design was based on Variation theory. Data consisted 45 pupilsgrade sixth. All students deepened their knowledge about what affects bloodcirculation. To show blood circulation as an interconnected system and how a liquidis transported in a interconnected system compared to a system with a preformationstudents could see that no matter where the fracture is all parts are affected.

No description available.

Submitted in fulfillment for the degree of Master of Technology, Clinical Technology: Cardiovascular Perfusion, Durban University of Technology, Durban, South Africa, 2016. / Introduction: A large volume of residual haemodilute blood remains in the cardiopulmonary bypass (CPB) circuit after termination of the bypass. It is common practice in many centres to process residual pump blood with an autologus cell salvage system (ACSS), thereby producing a re-suspended red blood cell (RBC) concentrate and attenuating the need for donor blood RBC concentrate. It has also become standard practice to wash donor pack red blood cells (PRBC) before adding it to neonate cardiopulmonary circuits (Swindell et al., 2007). Manufactures of ACSS recommend 0.9% sodium chloride (NaCl) as a wash solution for processing salvaged blood. Previous studies have demonstrated that washing PRBC with normal saline results in acid-base (Huber et al., 2013) and electrolyte derangements (Varghese et al., 2007). Infusion of normal saline in healthy volunteers also results in significant changes in osmolality (Williams et al., 1999). The use of normal saline as a wash solution in processing residual CPB blood requires investigation. Aims and Objectives: This was a prospective, quantitative in vitro investigation to analyze and compare the quality of residual pump blood post CPB that had been washed with either an unbalanced electrolyte solution (0.9% normal saline) or a balanced electrolyte solution (Balsol®). Both are crystalloid solutions. The primary objective of the present study was to measure and compare the pH, electrolytes, metabolites, osmolality and strong ion difference (SID) of residual pump blood to the pH, electrolytes, metabolites, osmolality and SID of processed cell saver blood, which was washed with either 0.9% normal saline or Balsol® solution. The secondary objective was to measure and compare protein levels (albumin and total protein) in residual pump blood to protein levels in processed cell saver blood, that is washed with either 0.9% normal saline or Balsol® solution. The final objective was to determine the volume, haematocrit and haemoglobin yield post cell saver processing, from the input volume of residual pump blood when washed with either 0.9% normal saline or Balsol® solution. This was the first study of this nature done in the South African population group. Methodology: In this investigation in a series of forty patients (n=40) undergoing elective cardiac surgery with CPB, the first twenty patients were allocated to the NaCl control group (n=20) and the second twenty patients were allocated to the Balsol® interventional group (n=20). The extracorporeal circuit consisted of a standard integral hollow fibre membrane oxygenator and tubing that was primed with 1500-1800 millilitres of balanced crystalloid solution (Balsol®), for both the control group and the interventional group, and addition of 5000 iu heparin. The balanced crystalloid solution (Balsol®) is the approved standard CPB priming solution for all cardiac procedures at Inkosi Albert Luthuli Central Hospital. This setup was used with the Stockert S5 roller pump heart lung machine. The operations were performed as per protocol with standard non-pulsatile CPB and hypothermia was maintained at 28 – 32 ºC (core) and haemodilution (haematocrit 20 % to 30 %). A standard flow rate of 2.4 L/min/m² was used. Cardio protection consisted of either cold Blood Cardioplegia using the Buckberg 4:1 ratio, being four parts blood to one part cardioplegia (with the 35ml of 20 % Dextrose + 1 gram Magnesium Sulphate added per 500ml), or 20ml/kg cold St Thomas II cardioplegia (with addition of 10ml of 8.5% NaHCO3 + 100mg lignocain per litre). Topical cooling was achieved with ice cold 0.9 % saline. Maintenance fluid used during CPB was Balsol® for both the control and the interventional groups. Calcium, potassium and sodium bicarbonate was administered as required during CPB to correct deficits for both groups. Weaning of CPB was performed after re-warming to a rectal temperature of at least 35 ºC for both study groups. Immediately on termination of CPB a blood sample was taken from the sampling manifold of the CPB circuit for pre wash analysis. Residual pump blood was then flushed out with one litre of Balsol® solution for both groups and collected into the Medtronic autolog cell saver reservoir to be processed. In the control study group 0.9% NaCl was used as the wash solution and in the interventional study group Balsol® solution was used as the wash solution. After processing of the salvaged blood is complete, a blood sample was taken for post wash analysis. Clinical data recorded for pre and post wash samples included: pH, pCO2, pO2, [K+], [Na+], [Cl-], [Ca2+], lactate, glucose, [HCO3-], TCO2, haematocrit, haemoglobin (GEM 4000® premier™ blood gas analyser) blood volume (Medtronic autolog) and SID (calculated as per equation). Inorganic phosphate, total magnesium, albumin, total protein (Siemens Advia 1800 blood gas analyser) and osmolality (Gonotech osmometer) were also measured. Results: There was a highly significant decrease (p < 0.05) within the NaCl group after washing with pCO2 (28.3 ± 2.9 vs. <6.0 ± 0.0), [K+] (4.5 ± 0.5 vs. 1.0 ± 0.7), total magnesium (1.7 ± 0.7 vs. 0.29 ± 0), ionized calcium (1.0 ± 0.09 vs. 0.1 ± 0.03), inorganic phosphate (0.9 ± 0.4 vs. 0.09 ± 0.04) and SID (27.1 ± 2.1 vs. 18.4 ± 2.2). There was a highly significant increase (p < 0.05) within the NaCl group after washing with pH (7.5 ± 0.1 vs. 7.7 ± 0.1), [Na+] (132.9 ± 3.2 vs. 146.3 ± 1.9), [Cl-] (107.8 ± 3.1 vs. 127.4 ± 2.1) and osmolaltity (256.9 ± 38.4 vs. 296.2 ± 57.5). There were highly significant decrease (p < 0.05) within the Balsol® group after washing with pCO2 (30.15 ± 6.0 vs. 18.9 ± 4.9), [Na+] (134.7 ± 2.2 vs. 125.6 ± 1), [Cl-] (108.8 ± 2.7 vs. 100.2 ± 1.4), ionized calcium (0.9 ± 0.1 vs. 0.02 ± 0.04), inorganic phosphate (0.8 ± 0.2 vs. 0.1 ± 0.024) and osmolality (288.8 ± 20.6 vs. 272.8 ± 19.9). There were highly significant increase (p < 0.05) within the Balsol® group after washing with pH (7.5 ± 0.1 vs. 7.7 ± 0.1), [K+] (4.2 ± 0.4 vs 4.6 ± 0.3). Total magnesium and SID were similar after washing within the Balsol® group. Albumin and total protein revealed similar significant decreases within both groups after washing. There was a highly significant difference (p < 0.05) in the change between groups after washing in all the variables measured, except for pH, inorganic phosphate, lactate, glucose, albumin, total protein, haematocrit, haemoglobin, and blood volume. Total carbon dioxide and [HCO3-] were not compared because they were incalculable by blood gas analyser in the NaCl group. Conclusion: This investigation concluded that the balanced electrolyte solution Balsol® used for washing residual CPB blood results in a re-suspended RBC concentrate, with an osmolality and electrolyte profile that is superior compared to washing residual CPB blood with 0.9% NaCl solution. / M

O presente estudo apresenta o desenvolvimento de uma Bomba de Sangue Ápico Aórtica (BSAA) para uso como dispositivo de assistência ventricular esquerda. A BSAA é um dispositivo que já se encontrava em desenvolvimento antes do início deste trabalho e o ponto de partida deste estudo foi a realização de ensaios In Vivo. Os ensaios In Vivo foram realizados em porcos (Landrace, sem gênero definido e massa de 45 a 90 Kg) o tempo de pós-operatório programado foi de 6 horas. Ao total foram realizados 7 experimentos, sendo que um dos experimentos não foi incluso na análise dos resultados devido a complicações na cirurgia. Em três experimentos, as 6 horas de pós-operatório foram cumpridas, em 1 experimento, o animal veio a óbito após 5h30 e em dois experimentos o animal veio a óbito antes da BSAA entrar em uso. Através dos ensaios In Vivo, foi possível implementar diversas melhorias no dispositivo, principalmente no sistema de conexão das cânulas. Foi realizado um ensaio para determinar a geometria de topo da cânula de entrada, mostrando que o modelo com cânula tubular simples é o mais adequado. Em um ensaio de durabilidade foram observadas duas falhas: o desacoplamento do rotor por desgaste do pivô inferior do mancal e uma fratura no eixo do mancal. A fratura no eixo foi analisada por uma simulação computacional. Foi proposta uma modificação no eixo do mancal para eliminar uma região com acúmulo de tensões. Para solucionar o degaste do pivô inferior foi proposta uma modificação na topologia do estator que, deixando de ser axial e se tornando radial. Para verificar o efeito do estator radial na redução do desgaste no mancal foi realizado um ensaio de desgaste, este ensaio mostrou a influência da carga no mancal em relação ao desgaste e serviu para fundamentar a implementação do estator radial. O protótipo da BSAA com estator radial foi construído. Neste modelo, foi possível reduzir o tamanho do dispositivo. Os resultados do ensaio para determinar o Índice Normalizado de Hemólise (INH) do modelo com estator radial mostraram que um INH clinicamente satisfatório. O estudo do desempenho hidrodinâmico do modelo com estator radial mostrou que o dispositivo é capaz de gerar pressão e fluxo para seu uso na assistência ventricular esquerda. Os resultados deste trabalho permitiram aprofundar o conhecimento sobre o desempenho da BSAA em condições reais de uso, possibilitando a melhoria do dispositivo e redução do desgaste visando seu uso em terapias de longo prazo. / This study presents the development of an Apico-Aortic Blood Pump (AABP) a left ventricle assist device. AABP is a device that was already in development before the beginning of this research and the starting point were Acute In Vivo experiments. The In Vivo experiments were performed in pigs (Landrace, gender not defined and weight 45 to 90 Kg), post operatory time was 6 hours. 7 experiments were performed and one of them was not included in the data analysis due to complications in the surgical procedure that lead to animal\'s early death and thus its exclusion. In 3 experiments, the 6 hours of post operatory were achieved, in one experiment the animal died after 5h30 minutes and in two experiments, the animal died before AAPB implantation. These In Vivo experiments allowed AAPB improvement mainly in the connection system. A study to select the edge geometry of the inlet cannulae was performed, the results appointed that a tube shape cannulae model would be more appropriated for the device ease implantation. In the durability test two failures occurred: rotor decoupling due to wear in the lower pivot of the bearing system and a fracture in the bearing axis. The fracture in the bearing axis was further studied by computer simulation, which results lead to a modification in the axis geometry to eliminate a region with accumulated tension. To solve wear problem in the lower pivot, a stator topology modification was explored, AABP\'s stator would became radial instead of axial as it was in the original model. In order to verify the effect of the radial stator in reducing wear on the lower pivot, a wear test was performed. In this test, the influence of load on the wear production rate was observed and the results appointed that reducing the load would reduce the wear. These results were the basis for stator change to the radial topology. An AAPB prototype with the radial stator was constructed and this model had lower dimensions than the original model with axial stator. Normalized Index of Hemolysis (NIH) obtained with the prototype with the radial stator was in the clinically satisfactory limit. Hydrodynamic performance of the model with the radial stator indicated that this device could provide pressure and flow for its use as a left ventricle assist device. Results from this thesis allowed a deeper knowledge from AABP performance in real use conditions, which lead to the improvement of the device and through this study was possible to know and implement features aiming to enhance AAPB\'s durability for its use in long-term therapies.

O presente estudo estudou os fatores de risco para aquisição de infecções da corrente sanguínea relacionadas com cateter (ICSACs) em unidades de terapia intensiva (UTIs), a incidência e etiologia da ICSACs em UTIs com perfis diferentes. Foi realizado através deum estudo prospectivo de coorte nos seguintes hospitais: Hospital Santa Casa de Misericórdia de SP (duas UTIs pediátricas - serviço público), Municipal Hospital Alípio Correa Neto:com oito leitos (serviço público), e no Hospital Israelita Albert Einstein: 15 leitos (serviço privado). Participaram os pacientes internados nas UTIs com idade de 1 mês a 18 anos de idade que utilizaram cateter venoso central (CVC) por mais de 24 horas. Realizou-se registro do progresso diário dos pacientes e fatores como dados gerais do paciente e relacionada a cateter foram coletadas e usadas como variáveis. Todos os dados foram analisados utilizando SPSS13.0, para comparar pacientes com ICSAC com ou sem fatores de risco. Dos 170 pacientes com CVC, 18,2% tinham ICSACs. Uso de dispositivos (por exemplo, cateter urinário e tubo endotraqueal), produtos derivados do sangue, infecções prévia ao uso do CVC, o uso de antifúngicos, distúrbios de potássio, número de punções, sinais de infecção local, número de cateteres, e uso de cateter foram associados como fatores de risco a ICSACs. As taxas de ICSAC observadas foram superiores aos descritos na literature internacional, e Bacilos Gram-negativos foram os microorganismos mais prevalentes / This study studied the risk factors for acquiring catheter-related bloodstream infections (CRBSIs) in intensive care units (ICUs) and the incidence and etiology of CRBSIs in ICUs with different profiles. It was a Prospective cohort study a ccomplished in the following hospitals: Hospital Santa Casa de Misericordia in SP ( with two pediatric ICUs - public), Municipal Hospital Alipio Correa Neto ( eight beds public), and Hospital Israelita Albert Einstein ( 15 beds -private). Patients Participated with 1 month to 18 years old who used Central Venous Catheter (CVC) for over 24 hours. We recorded patients\' daily progress. Factors such as general data of patient and catheter-related were collected and used as variables. All the data were analyzed using SPSS13.0, to compare patients with CRBSI with or without risk factors. Of the 170 patients with CVCs, 18.2% had CRBSIs. Use of devices (e.g., indwelling urinary catheter and endotracheal tube), blood products, previous infections, use of antifungals, potassium disorders, number of punctures, signs of local infection, number of catheters, and longer catheter usage were associated risk factors with CRBIs. The CRBSI rates observed were higher than those describe in the international literature, and the Gram-negative were the most prevalent microorganisms

Peng Zhiyong. / "December 2004." / Thesis (Ph.D.)--Chinese University of Hong Kong, 2004. / Includes bibliographical references (p. 146-175) / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Mode of access: World Wide Web. / Abstracts in English and Chinese.

Han, Jinghao. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2007. / Includes bibliographical references (p. 182-204). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstracts in English and Chinese.

Background. Diabetes mellitus is a complex metabolic disorder characterized by clustering of multiple cardiovascular risk factors. Diabetic albuminuria is associated with increased prevalence of both micro-vascular and macro-vascular complications. This thesis examined vascular function (Flow-mediated dilatation, FMD) in type 2 diabetic patients with particular emphasis on its relationships with nephropathy. Independent predictors for FMD in Chinese population using data from both diabetic and non-diabetic subjects as well as the predictive value of FMD on clinical endpoints and death in type 2 diabetic patients with nephropathy were examined. / Conclusions. In Chinese subjects with or without type 2 diabetes, hyperglycaemia, hypertriglyceridemia, smoking and albuminuria were independent predictors for FMD. Type 2 diabetic subjects with overt nephropathy had impaired endothelium-dependent and endothelium-independent dilatation, suggesting vascular dysfunction beyond the endothelium. In agreement with studies from Caucasians, smoking was the most important determinant for vascular dysfunction in Chinese type 2 diabetic patients with overt nephropathy. Furthermore, FMD was predictive of new onset of cardiovascular events and related death in Chinese type 2 diabetic patients with overt nephropathy. / In diabetic patients with overt nephropathy, smoking (current and ex-smokers), waist hip ratio (WHR) and serum creatinine were independent predictors for impaired FMD. The latter was predictive of advancement of IMT and was an independent predictor for new onset of combined cardiovascular diseases and related death after a follow up period of 42 months (log rank test=6.04, p=0.014 using Cox regression analysis) after controlling for all confounding factors. In addition, fasting total cholesterol and plasma glucose were predictive for all-cause mortality while serum creatinine predicted new onset of renal endpoint. In a subgroup analysis in diabetic patients with overt nephropathy, smokers who developed CVD or ESRD had greater diminution of FMD than those who did not develop clinical endpoints. / Methods and results. FMD was assessed using high-resolution ultrasound scan. In the cross-sectional study, the sample population was divided into four groups according to the presence or absence of type 2 diabetes and level of albuminuria. They included the non-diabetic group (N=52), diabetic group with normoalbuminuria (N=18), diabetic group with microalbuminuria (N=18) and diabetic group with overt nephropathy defined as macroalbuminuria and renal insufficiency (N=22). Compared to non-diabetic subjects, type 2 diabetic subjects with nephropathy had impaired FMD (4.54% +/- 2.25 vs. 2.50% +/- 2.31, p&lt;0.05) and impaired GTN-dependent dilatation (GTND) (14.30% +/- 3.77 vs. 12.70% +/- 4.70, p&lt;0.05). They also had reduced endothelium-dependent dilatation to endothelium-independent dilatation ratio when compared to non-diabetic subjects (0.19 +/- 0.17 vs. 0.32 +/- 0.15, p&lt;0.05). These findings suggest that the impaired vascular dilatation was due to dysfunction of both endothelium and vascular smooth muscle cells. In the entire cohort, fasting plasma glucose, fasting triglyceride, smoking and albuminuria were independent predictors for FMD. / Lai Wai Keung Christopher. / "February 2006." / Source: Dissertation Abstracts International, Volume: 67-11, Section: B, page: 6298. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2006. / Includes bibliographical references (p. 202-252). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstracts in English and Chinese. / School code: 1307.

O presente estudo estudou os fatores de risco para aquisição de infecções da corrente sanguínea relacionadas com cateter (ICSACs) em unidades de terapia intensiva (UTIs), a incidência e etiologia da ICSACs em UTIs com perfis diferentes. Foi realizado através deum estudo prospectivo de coorte nos seguintes hospitais: Hospital Santa Casa de Misericórdia de SP (duas UTIs pediátricas - serviço público), Municipal Hospital Alípio Correa Neto:com oito leitos (serviço público), e no Hospital Israelita Albert Einstein: 15 leitos (serviço privado). Participaram os pacientes internados nas UTIs com idade de 1 mês a 18 anos de idade que utilizaram cateter venoso central (CVC) por mais de 24 horas. Realizou-se registro do progresso diário dos pacientes e fatores como dados gerais do paciente e relacionada a cateter foram coletadas e usadas como variáveis. Todos os dados foram analisados utilizando SPSS13.0, para comparar pacientes com ICSAC com ou sem fatores de risco. Dos 170 pacientes com CVC, 18,2% tinham ICSACs. Uso de dispositivos (por exemplo, cateter urinário e tubo endotraqueal), produtos derivados do sangue, infecções prévia ao uso do CVC, o uso de antifúngicos, distúrbios de potássio, número de punções, sinais de infecção local, número de cateteres, e uso de cateter foram associados como fatores de risco a ICSACs. As taxas de ICSAC observadas foram superiores aos descritos na literature internacional, e Bacilos Gram-negativos foram os microorganismos mais prevalentes / This study studied the risk factors for acquiring catheter-related bloodstream infections (CRBSIs) in intensive care units (ICUs) and the incidence and etiology of CRBSIs in ICUs with different profiles. It was a Prospective cohort study a ccomplished in the following hospitals: Hospital Santa Casa de Misericordia in SP ( with two pediatric ICUs - public), Municipal Hospital Alipio Correa Neto ( eight beds public), and Hospital Israelita Albert Einstein ( 15 beds -private). Patients Participated with 1 month to 18 years old who used Central Venous Catheter (CVC) for over 24 hours. We recorded patients\' daily progress. Factors such as general data of patient and catheter-related were collected and used as variables. All the data were analyzed using SPSS13.0, to compare patients with CRBSI with or without risk factors. Of the 170 patients with CVCs, 18.2% had CRBSIs. Use of devices (e.g., indwelling urinary catheter and endotracheal tube), blood products, previous infections, use of antifungals, potassium disorders, number of punctures, signs of local infection, number of catheters, and longer catheter usage were associated risk factors with CRBIs. The CRBSI rates observed were higher than those describe in the international literature, and the Gram-negative were the most prevalent microorganisms