Associations between patient and procedural factors on the nature and quality of the immediate in-home recovery from anesthesia following ambulatory orthopedic surgery are unknown. Further, there is a paucity of outcomes research quantitatively categorizing in-home patient recovery and safety following discharge from same-day orthopedic procedures. Tools are available, however, to shed light on outcomes in this population, and integration of such available measures is critical. Ambulatory orthopedic surgery is a burgeoning specialty, with growth expected over the foreseeable future. The expected increased patient caseload subsequent to implementation of the Affordable Care Act and aging Baby Boom generation suggests greater morbidity and mortality is on the horizon unless aggressive measures are taken at mitigating risk. Similarly, as the obesity epidemic expands, obesity-related comorbid conditions including obstructive sleep apnea (OSA) are likely to grow. The purpose of this research was to explore the relationship between ambulatory orthopedic patient-reported activities (quality of life metrics) and diagnostic factors (physical and perioperative care data) in the immediate postoperative period that are predictive of arterial oxygen desaturation. Data was obtained using a novel patient journal exploring sleep, pain, nausea, tobacco use, alcohol use, and appetite in conjunction with a valid and reliable portable, wrist-worn pulse oximeter. Additional assessment data was taken from the preanesthetic assessment. All participants were scored according to the STOP-Bang questionnaire, an accepted survey of OSA risk. Patients were recruited from a busy metropolitan ambulatory surgery center in Richmond, Virginia that sees approximately 500 cases monthly, and a 309-bed tertiary care hospital in West Burlington, Iowa. The target sample included 52 individual patients with data collected over the first two post-operative nights following discharge. Two patients were excluded. Negative binomial regression, log10 transformation, and least-squares regression examined the relationships the STOP-Bang questionnaire, quality of life data, and physical perioperative data had on postoperative desaturation events. Results suggested the STOP-Bang score predicted desaturation events and that age and BMI were significant individual predictors. Opiate pain medication treatment, a happy mood, and home CPAP use were associated with decreased events. This study provided a unique perspective in patient safety research, relating human behaviors and experiences with postoperative oxygen desaturation. Future research projects aligned with postoperative monitoring, pulse oximetry, patient safety, and obstructive sleep apnea are potential following the findings of this study.

Τα τελευταία χρόνια τόσο σε διεθνές όσο και σε εθνικό επίπεδο έχει δοθεί βαρύτητα στην ανίχνευση της εμβρυϊκής υποξίας κατά τη διάρκεια της κύησης και του τοκετού, καθώς είναι σαφής η άμεση συσχέτισή της με βραχυπρόθεσμες και απώτερες επιπλοκές του νεογνού. Η επιτυχής έκβαση ενός τοκετού εξαρτάται κυρίως από τον έγκαιρο εντοπισμό της δημιουργίας της εμβρυϊκής υποξίας και η ανάγκη για την υλοποίηση υπολογιστικών συστημάτων για την έγκαιρη διάγνωσή της είναι συνεχής και αυξανόμενη. Στα πλαίσια της διδακτορικής διατριβής σχεδιάστηκε και αναπτύχθηκε ένα πρωτότυπο σύστημα διάγνωσης της πρόωρης οξέωσης του εμβρύου κατά τη διάρκεια του τοκετού, το οποίο βασίστηκε στην επεξεργασία του εμβρυϊκού καρδιακού ρυθμού και στην ανάλυση της εμβρυϊκής παλμικής οξυμετρίας. Στόχος του συγκεκριμένου συστήματος είναι να αποτελέσει ένα βοηθητικό σύστημα διάγνωσης της εμβρυϊκής υποξίας και να συμβάλει στη λήψη αποφάσεων σχετικά με το χρόνο αποπεράτωσης του τοκετού, με σκοπό την πρόληψη άμεσων και απώτερων σοβαρών νεογνικών επιπλοκών. Ειδικότερα, η υλοποίηση του προτεινόμενου συστήματος βασίστηκε στην εφαρμογή του συνεχούς μετασχηματισμού κυματιδίων και της προσαρμοστικής προσέγγισης με τη χρήση του αλγορίθμου matching pursuit για την ανάδειξη της «κρυμμένης» πληροφορίας που μεταφέρει ο εμβρυϊκός καρδιακός ρυθμός στις πολύ χαμηλές συχνότητες. Συνδυάζοντας τα αποτελέσματα των παραπάνω τεχνικών επεξεργασίας, και ιδιαίτερα του αλγορίθμου matching pursuit, με τον προσδιορισμό του συνολικού χρόνου χαμηλού κορεσμού του αρτηριακού εμβρυϊκού αίματος, υλοποιήθηκε, με τη χρήση ενός διαμεριστικού αλγορίθμου, το προτεινόμενο σύστημα. Η ανάπτυξη αυτού του συστήματος αποτελεί μια καινοτόμα και πολλά υποσχόμενη προσέγγιση στην προσπάθεια της διάγνωσης της εμβρυϊκής υποξίας δεδομένου ότι παρουσιάζει υψηλή ειδικότητα και θετική προγνωστική αξία συμβάλοντας στην επίλυση του σοβαρότερου μειονεκτήματος της κλασσικής καρδιοτοκογραφίας που είναι η χαμηλή τιμή των αντίστοιχων προγνωστικών δεικτών. / In the last few years the research community has given great attention to the detection of antepartum and intrapartum fetal hypoxia, given its direct impact on both short- and long-term neonatal morbidity and mortality. The successful completion of labor depends mainly on the prompt identification of fetal hypoxia. The development of computational systems for the early diagnosis of restricted fetal oxygen supply is therefore of critical importance. This thesis involves the design and development of an innovative system for the early detection of acidosis, which was based on the fetal heart rate processing and fetal pulse oximetry analysis. The aim of the system is to comprise a computer-aided diagnostic system of fetal hypoxia and to contribute to the decision making regarding the labor completion time, in order to prevent short- and long-term neonatal complications. Specifically, the development of the system was based on the implementation of continuous wavelet transform and adaptive approximation using the matching pursuit algorithm, in order to reveal the “hidden” information conveyed in the very low frequency range of the fetal heart rate. The system involves the combination of the results of the above-mentioned processing techniques, and especially of the matching pursuit algorithm, along with the calculation of the duration of fetal arterial low oxygen saturation, applying a commonly used clustering algorithm. The proposed system is an innovative and promising approach towards the early diagnosis of fetal hypoxia, given its high specificity and positive predictive value, thus effectively addressing the major drawback of clinical cardiotocography.

Τα τελευταία χρόνια, οι μη επεμβατικές μέθοδοι διάγνωσης αλλά και θεραπείας κερδίζουν συνεχώς έδαφος έναντι των παραδοσιακών επεμβατικών μεθόδων. Σκοπός της διπλωματικής αυτής εργασίας είναι η μελέτη της μετάδοσης του φωτός μέσα στο ανθρώπινο δέρμα και κυρίως η μελέτη της απορρόφησης που υφίσταται από αυτό, με σκοπό την μέτρηση βιολογικών συντελεστών, όπως οι συγκεντρώσεις κάποιων ουσιών στον οργανισμό, ο υπολογισμός των οποίων μπορεί να οδηγήσει σε χρήσιμα διαγνωστικά συμπεράσματα. Επίσης, αναλύεται η μέθοδος της παλμικής οξυμετρίας, που χρησιμοποιείται ευρύτατα για την παρακολούθηση του αρτηριακού κορεσμού οξυγόνου και του καρδιακού παλμού. Μετρώντας την απορρόφηση του φωτός σε δύο διαφορετικά μήκη κύματος, ένα στο ερυθρό (660 nm) και ένα στο εγγύς υπέρυθρο (940 nm), και απομονώνοντας το μεταβαλλόμενο μέρος αυτής, που οφείλεται στις διακυμάνσεις στον όγκο του αρτηριακού αίματος, μπορούμε να υπολογίσουμε με τη χρήση του νόμου των Beer-Lambert τον κορεσμό του αίματος σε οξυγόνο μέσω του υπολογισμού των συγκεντρώσεων του σε μειωμένη αιμογλοβίνη και σε οξυαιμογλοβίνη. Τέλος, περιγράφεται η υλοποίηση της μεθόδου και ο σχεδιασμός ενός παλμικού οξυμέτρου ενός chip με τη χρήση του μικροεπεξεργαστή MSP430. / Over recent years, non-invasive methods of diagnosis and treatment are gaining ground against the traditional invasive methods. In this thesis, an integrated review of the transfer of optical radiation into human skin and primarily light absorption through human skin is presented, aiming at measuring biological information, such as concentrations of certain substances in the human body, whose calculation can lead to useful diagnostic conclusions. The method of Pulse Oximetry, which is widely used for monitoring arterial oxygen saturation and heart rate of a patient, is also presented. By measuring the absorption of light at two different wavelengths, one red (660 nm) and one near-infrared (940 nm), and isolating its AC component, which is a result of the variations in the volume of arterial blood, we can calculate the oxygen saturation using the Beer-Lambert law, by estimating the concentrations of oxyhemoglobin and reduced hemoglobin. Moreover, the implementation of a single chip portable pulse oximeter using the ultra low power capability of the MSP430 is demonstrated.

Disfagia orofaríngea ocorre em pacientes após cirurgias cardíacas e prolonga o tempo de internação. O objetivo da presente Tese foi identificar as características da deglutição nos cardiopatas idosos indicados à cirurgia de Revascularização Miocárdica. Foi utilizado um protocolo combinado de deglutição de água, ausculta cervical e monitorização dos sinais vitais. O registro da freqüência cardíaca e da saturação de oxigênio (FC e SpO2) foi realizado com oxímetro de pulso antes, durante e após o teste de deglutição de água com 1,3,5,10, 15 e 20 ml. A ausculta cervical foi realizada com estetoscópio eletrônico para a análise do número, tempo de resposta e classificação do som da deglutição. Foram registradas a freqüência respiratória (FR) e a presença de tosse e engasgo. Os resultados foram analisados através de dois estudos. O primeiro avaliou 60 idosos saudáveis, sendo 45 mulheres e 11 homens, com média de idade de 74,5 anos. Os resultados mostraram aumento da FC durante o teste e diminuição logo após. Houve aumento de SpO2 e FR após o teste. Houve deglutição única em todas as medidas exceto em 20 ml. O tempo de resposta da deglutição em todos os volumes foi menor que 1 segundo exceto em 1 e 3 ml. A ausência de tosses e engasgos foi predominante. O som do tipo 3 predominou em todos os volumes exceto em 20 ml onde predominou o som do tipo 1. Concluindo, as características da deglutição dos idosos saudáveis representaram alterações compatíveis com as mudanças fisiológicas decorrentes da idade e não evidenciaram a disfagia. No segundo estudo, 38 idosos com doença arterial coronária constituíram o Grupo de Pesquisa (GP) e foram comparados a 30 idosos saudáveis no Grupo Controle (GC). Foram avaliados 27 homens e 11 mulheres no GP, com média de idade de 68 anos. No GC foram avaliados 15 homens e 15 mulheres, com idade média de 70 anos. Houve diferença significativa no tempo de resposta da deglutição nos cardiopatas com FC abaixo de 60 , sendo mais curto em 3 ml, 10 ml, 15 ml e 20 ml. A FC permaneceu mais baixa nos cardiopatas. Não houve diferença significativa nos outros parâmetros, ou seja, os idosos cardiopatas foram semelhantes aos idosos saudáveis, exceto pelo tempo curto para a resposta da deglutição. Concluindo, a presente pesquisa mostrou que os idosos cardiopatas apresentam diferença na função de deglutição em relação aos idosos saudáveis. Os cardiopatas apresentam alterações da coordenação temporal entre respiração e deglutição, revelando risco para a disfagia. As técnicas de ausculta cervical e oximetria de pulso favoreceram a análise objetiva desses dados. / Oropharyngeal dysphagia affects patients after heart surgery and increases the length of the hospitalization. The objective of the present research was to identify the swallowing function caractheristics of aged people with heart diseases who were referred to the coronary artery surgery. A combined protocol of sign vital monitoring and water swallowing evaluation was used together with cervical auscultation. The heart rate (HR) and oxygen saturation (SpO2) were recorded by pulse oximetry before, during and after the water test for 1,3,5,10,15 and 20 ml. Cervical auscultation was done by electronic stethoscope in order to analyse the number, time of swallowing response and swallowing sound classification. Respiration rate (RR), cough and choking were recorded. The results were analysed by two studies. In the first one, sixty healthy aged individuals were assessed. There were 45 women and 11 men; mean age was 74,5 years. There were SpO2 and RR increasing after the water test. There were single swallow for all volume except 20 ml. The time of swallowing response for all volumes occurred before 1 second except for 1 and 3 ml. Cough and choking were not predominant in the water test. The type 3 sound was predominant for all volumes except 20ml where there was type 1 sound. In summary, the characteristics of swallowing in healthy aged individuals represented alterations due to physiological changes in aging and there was no evidence of dysphagia. In the second study, 38 aged subjects with coronary artery disease composed the research group (RG) and they were compared to 30 healthy aged subjects in the control group (CG). There were 27 men and 11 women assessed in the RG; mean age was 68 years. There were 15 women and 15 men assessed in the CG, mean age was 70 years. There was significant difference in the time of swallowing response in the RG when HR was below 60. It was shorter for 3, 10, 15 and 20 ml. HR was minor in heart disease individuals. There were no significant difference in other parameter, that is, aged patients with heart disease were similar to healthy aged individuals, except for the short time of swallowing response. Therefore, the present study presented a different swallowing function between aged patients with heart disease and healthy aged individuals. The heart disease patients have alterations in the temporal coordination between swallowing and respiration function, disclosing risk of dysphagia. Cervical auscultation and pulse oximetry were advantageous for the objective analysis of the data.

Introdução: A piora da função muscular respiratória pós-cirurgia aumenta o risco de hipoventilação, hipóxia, atelectasia e infecções. O fisioterapeuta tem um papel essencial na recuperação desses pacientes. O objetivo da pesquisa foi avaliar se a intervenção da fisioterapia respiratória no pós-operatório imediato de pacientes submetidos à cirurgia abdominal alta eletiva, em sala de recuperação pós-anestésica, resulta em melhor função pulmonar, observando valores de espirometria e oximetria de pulso e dados da evolução clínica. Métodos: O estudo é do tipo ensaio clínico prospectivo e aleatorizado observando-se valores de espirometria e oximetria de pulso. Também foi realizada análise retrospectiva dos prontuários. Os grupos foram avaliados no pré-operatório e no segundo pós-operatório (espirometria, oximetria de pulso, exame físico, escala analógica de dor). O grupo experimental recebeu fisioterapia respiratória na recuperação pós-anestésica. Resultados: Não houve diferença entre os valores espirométricos, de pico de fluxo expiratório e de saturação de oxigênio entre os grupos controle e experimental. No presente estudo a saturação de oxigênio melhorou após a fisioterapia (p=0,029). Porém essa melhora não se manteve até o segundo pós-operatório. Também foi avaliado o tempo de internação, tempo cirúrgico, escala analógica de dor e complicações pós-operatórias, não houve diferenças entre os grupos. Conclusões: A espirometria não se mostrou sensível para detectar eventual piora da função pulmonar no segundo pós-operatório. A saturação de oxigênio atingiu números próximos aos do pré-operatório após exercícios de fisioterapia. A fisioterapia respiratória no pós-operatório imediato não causou dor ao paciente / Introduction: Surgical procedures can affect the respiratory muscles increasing the risks to hypoventilation, hypoxia, atelectasis and infections. Physiotherapists are essentials to care those patients. The purpose of this study was to evaluate the intervention of chest physiotherapy in immediate postoperative, in anesthesia recovery period room, analyzing lung functions, spirometry and oximetry in patients submitted to elective abdominal surgery. Methods: Clinic prospective and arbitrary, observing spirometry and oxygen saturation. A retrospective analysis from the notes was also done. The groups were evaluated in preoperative and 2nd postoperative (spirometry, oxygen saturation, physic examination and graduated pain scale).The physiotherapy group received chest physiotherapy in recuperation post anaesthetic. Results: There is no evidence to support a significant difference between control group and physiotherapy group analyzing spirometric values, expiratory peak flow and oxygen saturation. The oxygen saturation improves after physical therapy (p=0,029). But this improve can\'t kept until second postoperative. The period in hospital, surgery duration, graduated pain scale and postoperative pulmonary complications were analyzed but there was not significant difference between groups. Conclusions: Spirometry was not able to show a possible worst in pulmonary function on the second postoperative. The oxygen saturation reached similar numbers to preoperative post chest physiotherapy. In immediate postoperative chest physiotherapy do not cause pain to the patient

Submitted by Fabiana Gonçalves Pinto (benf@ndc.uff.br) on 2015-10-14T17:08:25Z No. of bitstreams: 1 Roberta Neves.pdf: 2013363 bytes, checksum: 02dd0656ebbb2438dc6715d64f374fdb (MD5) / Made available in DSpace on 2015-10-14T17:08:25Z (GMT). No. of bitstreams: 1 Roberta Neves.pdf: 2013363 bytes, checksum: 02dd0656ebbb2438dc6715d64f374fdb (MD5) Previous issue date: 2014 / Mestrado Profissional em Enfermagem Assistencial / O estudo aborda os processos de limpeza e desinfecção dos principais dispositivos de monitoramento não críticos (termômetros, esfigmomanômetro, cabos de eletrocardiograma e oxímetro) considerando a sua participação na transmissão das infecções relacionadas à assistência à saúde. Estes equipamentos têm sido apontados como uma das principais fontes de infecção por bactérias multirresistentes causadoras de surtos infecciosos em ambiente hospitalar portanto, exigem padronização da limpeza e desinfecção, mediante um protocolo que norteie o processo de trabalho. Este estudo teve como objetivos: elaborar um protocolo de limpeza/desinfecção dos principais dispositivos de monitoramento não críticos, com base nas boas práticas e evidências na literatura, e validar este protocolo com avaliação de experts em infecção hospitalar. Trata-se de estudo descritivo e exploratório, que no seu desenvolvimento seguiu as seguintes etapas: revisão integrativa da literatura, elaboração do protocolo de limpeza e desinfecção dos principais dispositivos de monitoramento não críticos e validação do protocolo por experts em infecção hospitalar. A elaboração do protocolo ocorreu a partir das boas práticas identificadas nos estudos selecionados na revisão integrativa, livros, teses, dissertações e documentos de órgãos nacionais e internacionais sobre a temática. Para validação do protocolo foram selecionados cinco experts em infecção hospitalar, de acordo com os critérios de seleção sugeridos no estudo. Após avaliação de cada recomendação do protocolo proposto, em um questionário, foi calculado o grau de concordância entre eles por média ponderada. A partir da análise dos registros dos experts e, considerando o grau de concordância das respostas, foi elaborado o protocolo final. Assim, respondendo aos objetivos do estudo, inicialmente tem-se o protocolo construído a luz do conhecimento científico que foi chancelado por um grupo de experts gerando o protocolo final. Este protocolo é portanto, o produto desta pesquisa e com ele pretende-se padronizar os processos de limpeza e desinfecção destes dispositivos, visando preencher as lacunas do conhecimento teórico/prático identificadas sobre a temática e reduzir os riscos de transmissão de infecção por estes artigos. Este protocolo será proposto à Comissão de Controle de Infecção Hospitalar da Secretaria Estadual de Saúde do Rio de Janeiro, a fim de implementá-lo nas unidades de pronto atendimento 24 horas (UPAs 24hs) testando sua aplicabilidade e futuramente sua eficácia. / The study discusses the procedures of cleaning and disinfection of the main non-critical monitoring devices (thermometers, sphygmomanometer, electrocardiography wires and oximeters wires) considering their participation in the transmission of infections related with health care. These equipments have been identified as the major source of infection by multiresistant bacteria that causes hospital infections, therefore, require standardization of cleaning and disinfection, by using a protocol that guides the work process. This study aims to: develops a protocol for cleaning / disinfection of the main non-critical monitoring devices, based on best practices and evidence in the literature, and validate this protocol with assessment of experts in hospital infections. It is descriptive and exploratory study, which involved the following steps: integrative literature review, development of the protocol for cleaning and disinfection of the main devices of non-critical monitoring and a validation of this protocol by the experts of hospital infection. The protocol development is based on best practices identified in the studies selected in integrative review, books, thesis, dissertations and national and international documents on the subject. To validate the protocol, five experts in hospital infection were selected according to the selection criteria suggested in the study. After evaluating each recommendation of the proposed protocol, in a questionnaire, the degree of agreement was calculated by weighted average. From the analysis of the observations of experts and considering the degree of agreement of answers, a final protocol was developed. So, to answer the aim of this work, first of all, a protocol was developed with scientific knowledge and afterward judged by some experts, which leads to a final protocol. Therefore this final protocol is the result of this study and it is intended to standardize the process of cleaning and disinfection of these devices, fill gaps in theoretical/practical knowledge on the subject and reduce the risk of infection transmission by these objects. These protocol will be proposed to the of Hospital Infection Control Committee at the State Department Health of Rio de Janeiro, to implement it in emergency care unit (called “UPAs 24 hs”) testing its applicability and future effectiveness.

Le glaucome est une neuropathie optique progressive caractérisée par une perte des fibres nerveuses ganglionnaires. Cette atteinte provoque une diminution graduelle du champ visuel pouvant mener à la cécité. Cependant, le glaucome est présent chez plusieurs patients qui ne présente pas une pression intraoculaire élevée et plusieurs patients ayant une pression intraoculaire anormalement élevée ne développent pas le glaucome. Pour mieux comprendre la pathophysiologie de la maladie, plusieurs chercheurs se sont intéressés aux composantes hémodynamiques de l’œil. L’oxymétrie oculaire est représentée par plusieurs technologies commercialement disponibles qui proposent de mesurer de façon non invasive la saturation en oxygène des structures vasculaires de l’œil. Plusieurs études ont évaluées l’association entre l’état d’oxygénation des différentes structures rétiniennes et le glaucome. L’objectif de cette étude était de vérifier la répétabilité des mesures d’oxymétrie à la tête du nerf optique obtenues avec l’appareil Zilia ainsi que d’étudier l’acquisition afin de déterminer les caractéristiques nécessaires pour obtenir des résultats optimaux. De plus, cette étude a comparé la saturation en oxygène (SaO2) mesurée sur la tête du nerf optique de sujets normaux et de personnes atteintes de glaucome. Une corrélation a aussi été faite entre les valeurs d’oxymétrie et les différentes variable affectées dans le glaucome Ceci est une étude prospective à mesures répétées et à cas-témoins. Les participants ont été recrutés à l’Institut de l’œil des Laurentides. Les participants complétaient un examen oculovisuel complet en plus d’une mesure de la pression artérielle et de la saturation en oxygène pulsée (SpO2). Les valeurs de l’oxymétrie oculaire étaient obtenues avec l’appareil Zilia sur la portion temporale du nerf optique et le logiciel intégré permettait d’obtenir la valeur moyenne de l’acquisition. Aucune différence statistiquement significative n’a été obtenue entre la moyenne des trois mesures de la SaO2 au niveau du nerf optique. Pour la durée de l’acquisition, l’analyse des données a démontré une différence statistiquement significative entre les différentes durées sélectionnées, démontrant une différence entre les acquisitions d’une durée de 5 secondes comparativement aux autres durée d’acquisition. Il n’y avait pas de différence statistiquement significative entre la moyenne de la première mesure obtenue avant et après l’utilisation de la technique d’optimisation. Les résultats indiquent aussi une différence significative entre les valeurs moyennes de SaO2 mesurées à la tête du nerf optique des sujets glaucomateux comparativement aux sujets normaux. On note également une corrélation significative entre les valeurs de SaO2 et le RNFL global obtenu avec l’OCT. Cette étude constitue l’une des premières effectuées avec l’appareil Zilia. Les valeurs moyennes de la SaO2 obtenues à un point précis du nerf optique acquis par l’appareil Zilia sont répétables et une acquisition de 10 secondes pourrait permettre d’obtenir une valeur adéquate. La SaO2 mesurée par l’appareil Zilia sur la tête du nerf optique est diminuée chez les patients atteints de glaucome comparativement aux sujets sains. Il semble aussi avoir une relation entre la valeur de la SaO2 et l’épaisseur du RNFL. Plus d’études sont nécessaires afin d’établir le rôle de cet appareil dans le diagnostic et la gestion des patients atteints de glaucome. / Glaucoma is a progressive optic neuropathy characterized by loss of the retinal nerve fibers layer. This disease causes a decrease in the visual field that can lead to blindness. The main risk factor for glaucoma is the increase of intraocular pressure. However, not all glaucoma patients have an elevated intraocular pressure and many patients continue to progress despite good intraocular pressure control with current therapies. Several authors have focused on the hemodynamic components of the eye. They obtained significant differences in these factors between normal and glaucoma patients. Ocular oximetry is technology that can non-invasively measure oxygen saturation of eye tissues. Several studies have verified the association between ocular oximetry and glaucoma. The Zilia device uses diffuse spectroscopic reflectance to measure oxygen saturation at a specific point. The objective of this study was to verify the repeatability of the oximetry measurements on the head of the optic nerve obtained with the Zilia device and to study the acquisition in order to determine the characteristics necessary to obtain it optimally. Also, we measured the oxygen saturation (SaO2) on the optic nerve of normal subjects and compared it with patients with glaucoma. Additionally, the SaO2 was correlated with different variables affected by glaucoma. This is a prospective repeated-measures and case-cohort study. Participants were recruited at the Laurentian Eye Institute (IOL). They completed a complete eye exam under pupil dilation including a blood pressure measurement with an automated device and the pulse oximetry was obtained by a pulse oximeter (SpO2). The ocular oximetry measures was acquired by the Zilia imaging system on the temporal side of the optic nerve. No statistically significant differences were observed between the average of three SaO2 measurements at the optic nerve. For the duration of the acquisition, the data analysis showed a statistically significant difference between the 5 seconds acquisition compared to the other acquisition duration. There was no statistically significant difference between the average of the first measurement obtained before and after the use of the data optimization technique. The result showed a significant difference in the SaO2 values between glaucomatous participants and normal. We also see a correlation statistically significantly between the SaO2 values and the global RNFL. This study is one of the first one done with the Zilia device. The average value of SaO2 obtained at a specific point of the optic nerve acquired by the Zilia device are repeatable and a 10-second acquisition could provide a precise value. Also, the SaO2 measured with the Zilia imaging system on the optic nerve is significantly lower in glaucoma patients compared to normal patients. More studies are needed to really establish the role of that device in the diagnostic and fully up of patients with glaucoma.

"Non-invasive remote physiological monitoring of soldiers on the battlefield has the potential to provide fast, accurate status assessments that are key to improving the survivability of critical injuries. The development of WPI’s wearable wireless pulse oximeter, designed for field-based applications, has allowed for the optimization of important hardware features such as physical size and power management. However, software-based digital signal processing (DSP) methods are still required to perform physiological assessments. This research evaluated DSP methods that were capable of providing arterial oxygen saturation (SpO2), heart rate (HR), heart rate variability (HRV), and respiration rate (RR) measurements derived from data acquired using a single optical sensor. In vivo experiments were conducted to evaluate the accuracies of the processing methods across ranges of physiological conditions. Of the algorithms assessed, 13 SpO2 methods, 1 HR method, 6 HRV indices, and 4 RR methods were identified that provided clinically acceptable measurement accuracies and could potentially be employed in a wearable pulse oximeter."

L’objectif ici était de développer une méthode de détection des tumeurs cérébrales via des agents de contraste pour l’IRM du 19F à 7 teslas. Nous évaluons en particulier le potentiel de cette méthode à mettre en évidence l’angiogenèse tumorale à l’aide d’agents de contraste fonctionnalisés avec le peptide RGD et ciblant l’intégrine ανβ3, biomarqueur surexprimé à la surface des néo-vaisseaux irriguant la tumeur. Du fait des basses concentrations locales en agent de contraste, les efforts portent dans un premier temps sur l’optimisation d’une séquence multi échos de spin dédiée à l’imagerie du PFOB (perfluorooctyl bromure), perfluorocarbure biocompatible choisi pour constituer la base de nos agents de contraste. Nous montrons qu’un paramétrage minutieux de cette séquence permet la suppression de la J-modulation et un rehaussement du T2, conduisant à une excellente sensibilité in vitro. La séquence est ensuite testée pour des mesures d’oxygénation dans le foie et la rate chez la souris, après injection d’une émulsion de PFOB. Les résultats indiquent une très bonne précision des mesures après injection d’une seule dose d’émulsion. Notre séquence est également utilisée pour réaliser une étude de biodistribution dynamique, permettant de suivre l’accumulation des nanoparticules d’émulsion dans le foie et la rate juste après injection. Nous montrons par ailleurs qu’il est possible d’évaluer la furtivité d’émulsions contenant différentes quantités de PEG (Poly Ethylène Glycol) en ajustant les données expérimentales sur un modèle pharmacocinétique empirique. La séquence est enfin utilisée pour détecter des nanoparticules d’émulsions fonctionnalisées pour cibler l’intégrine ανβ3 dans un modèle souris U87 de glioblastome. Nous comparons les concentrations en agent de contraste obtenues dans la tumeur avec une émulsion contenant le peptide RGD, et une émulsion contrôle. Les résultats indiquent des concentrations significativement plus élevées avec l’émulsion RGD qu’avec l’émulsion contrôle, supposant un ciblage spécifique d’ανβ3 par les nanoparticules fonctionnalisées. Un dernier chapitre est dédié à une nouvelle méthode de spectroscopie de diffusion en 19F, dont le but est d’éliminer le signal vasculaire provenant des nanoparticules de PFOB circulantes afin d’évaluer le signal ne provenant que des particules liées. / This study aimed at developing a method for detection of brain tumors at 7 teslas thanks to 19F MRI contrast agents. We particularly assessed the potential of this method to highlight tumor angiogenesis with RGD-functionalized contrast agents targeting ανβ3 integrin, a biomarker over-expressed at the surface of new capillary blood vessels. Owing to low local concentrations in contrast agent, the first step consisted in optimizing a multi spin echo sequence dedicated to a well-known biocompatible perfluorocarbon, perfluorooctylbromide (PFOB). We show that careful adjustment of sequence parameters allows cancellation of J-modulation and T2 enhancement, and yields an excellent sensitivity in vitro. Our sequence was then tested for oxygenation measurements in the mouse liver and spleen after injection of a PFOB emulsion. The results demonstrate very good accuracy of the measurements after one single infusion of emulsion. We also perform a dynamic biodistribution study in order to monitor emulsion nanoparticle uptake in the liver and spleen. Moreover, we show that stealth of emulsions grafted with different quantities of polyethylene glycol (PEG) can be assessed by fitting experimental data with a pharmacokinetic empirical model. Our sequence was finally used to visualize ανβ3-targeted nanoparticles in a U87 glioblastoma mouse model. Concentrations found in tumors after injection of an RGD-functionalized emulsion and a control emulsion are compared. Concentrations are found to be significantly higher with the RGD emulsion than with the control emulsion, suggesting specific binding of functionalized nanoparticles with ανβ3 integrin. The last part is dedicated to a new diffusion-weighted 19F NMR spectroscopy sequence. This method aims at suppressing vascular signal coming from circulating PFOB nanoparticles in order to evaluate signal coming from bound nanoparticles only.

<p>Systemic infection, major surgery, trauma and many other causes can lead to impaired organ function. Compensated shock is not detected by global hemodynamic and oxygen measurements, as they take no account for regional variations. Focus has therefore gradually turned from looking at systemic changes to selective investigations of regional blood flow and ischemia. This thesis presents a series of experiments evaluating new application and validation of various monitoring techniques.</p><p>An experimental porcine model with anesthetized and invasively monitored animals was used. The circulatory interventions included endotoxin infusion (septic shock), aortic constriction and selective clamping of splanchnic arteries. The aim was to compare air with saline tonometry, to validate the intraperitoneal use of tonometry and to reexamine the use of endoluminal reflectance pulse oxymetry. To investigate the relative contributions of regional blood flow and detection of ischemia, measurements of hepatic venous oxygen saturation (ShvO₂), lactate concentrations and PCO₂ gap were used.</p><p>Our findings support the use of air instead of saline as the preferred technique for tonometric measurements. With the intraperitoneal application of tonometry we gain more information on regional aspects of the splanchnic circulation, and it appears to be a reliable monitoring option for early detection of ischemia in the small intestine. Measurements of ShvO₂will give an overall reflection of the intestinal circulation. The sigmoid colonic pulse oximetry showed a non-linear response in relation to regional blood flow, and will therefore not be able to detect gradual changes in oxygen saturation. Determination of the regional to endtidal PCO₂ gap might prove valuable for monitoring of the intestinal circulation.</p><p>Because of sophisticated interactions between portal and hepatic arterial blood flow and hepatic compensation for regional ischemia, a combination of monitoring techniques might be needed. The results of this study will hopefully encourage clinical evaluation of intraperitoneal tonometry and endtidal PCO₂ gap recordings for non-invasive, semi-continuous, trend monitoring of the splanchnic circulation.</p>