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Bakgrund: Synen är ett av våra viktigaste sinnen för att samla information om omgivningen. Under 2023 vårdades ca 6000 personer i Sverige med respiratorbehandling på intensivvårdsavdelningar. Upp till 40% av dessa patienter drabbas av ögonkomplikationer. Många patienter på intensivvårdsavdelningar förlorar ögonens normala funktioner, inklusive tårproduktion och blinkreflex, vilket kan leda till skador. Faktorer som sugning av luftväg, PEEP, sederande läkemedel och muskelrelaxantia kan bidra till detta i större utsträckning i samband med respiratorbehandling.  Syfte: Att beskriva intensivvårdssjuksköterskors erfarenheter av ögonvård hos patienter med respiratorbehandling.  Metod: För studien användes en kvalitativ metod med deskriptiv design. Totalt intervjuades 10 deltagare rekryterade genom ett ändåmålsenligt urval. En kvalitativ innehållsanalys har använts vid dataanalysering. Huvudresultat: Intensivvårdssjuksköterskor beskrev att de initialt hade begränsad erfarenhet av ögonvård, men införandet av en vårdrutin om ögonvård ökade uppmärksamheten kring ämnet. Deltagarna beskrev en medvetenhet om riskfaktorer för ögonkomplikationer, men påpekade att bristen på tydligt synliga symtom ibland kunde påverka följsamheten. Utmaningar identifierades i att utföra ögonvård, särskilt gällande prioritering, hög arbetsbelastning och vid speciella behandlingsmetoder, såsom bukläge. Intensivvårdssjuksköterskorna uttryckte en efterfrågan om ytterligare utbildning och förståelse för ögonvårdens betydelse vid respiratorbehandling.  Slutsats: För att möta utmaningarna som intensivvårdssjuksköterskorna står inför vid behandling av patienter med respiratorbehandling och för att fördjupa förståelsen kring ögonvårdens betydelse, behövs utbildningsinsatser. Väl implementerade vårdrutiner kan även bidra till att säkerställa att ögonvården utförs korrekt och kan därigenom leda till att minska vårdlidandet bland intensivvårdspatienterna. / Background: Vision is one of our most important senses for gathering information about our surroundings. In 2023, approximatley 6000 individuals received respiratory treatment in intensive care units in Sweden. Up to 40% of these patients suffer from eye complications. Many patients in intensive care units lose normal eye functions, including tear production and the blink reflex, which can lead to injuries. Factors such as airway suctioning, PEEP, sedative medications, and muscle relaxants may contribute to this in connection with respiratory treatment.  Aim: To describe intensive care nurses experiences of eye care for patients undergoing respiratory treatment.  Method: A qualitative method with a descriptive design was used for the study. A total of 10 participants were interviewed, recruited through purposive sampling. Qualitative content analysis was used for data analysis. Main Results: Intensive care nurses described initially having limited experience in eye care, but the implementation of a care routine for eye care increased attention to the subject. Participants described an awareness of risk factors for eye complications, but pointed out that the lack of clearly visible symptoms could sometimes affect compliance. Challenges were identified in performing eye care, especially regarding prioritization, high workload, and in special treatment methods, such as prone positioning. Intensive care nurses expressed a demand for further education and understandning of the importance of eye care during respiratory treatment.  Conclusion: To meet the challenges faced by intensive care nurses in treating patients undergoing respiratory treatment and to deepen the understanding of the importance of eye care, educational efforts are needed. Well-implemented care routines can also contribute to ensuring that eye care is performed correctly and can thereby potentially reduce patient suffering among intensive care patients.

Tesis por compendio / [EN] Intensive (broiler) poultry farming is a strategic sector for the economy and development of many countries and regions, including Spain and the Valencian Community region. Intensive production consists of keeping the animals in specific buildings (broiler buildings) under a controlled indoor microclimate. Two main options are found regarding the ventilation systems: production in broiler buildings with natural ventilation and production in broiler buildings with mechanical ventilation (commonly with negative depression by exhaust fans). Inadequate design is the main cause of thermal stress and the mortality of broilers. In this sense, one solution to decrease the broilers' heat stress and mortality consists of assisting in their biological thermoregulation by increasing the air velocity over them. In this PhD dissertation, the ventilation (ranges of the air velocity and its distribution, mainly at the level and plane where the broilers are located) in the main mechanical ventilation systems installed in the broiler buildings is characterised and analysed. Despite the magnitude of the current difficulties (broilers' thermal stress and mortality) and society's sensitivity regarding aspects of animal welfare, to date, the different mechanical ventilation systems in the different types of broiler building have not been characterised and analysed with scientific scrupulousness. In this PhD dissertation, the three most relevant types have been studied: cross, tunnel and single-sided. The methodological approach has been very similar in all the cases of study: some measurements by means a multi-sensor system (with our own original design and building) has been used for isotemporal recordings, the corresponding Computational Fluid Dynamics (CFD) simulations have been carried out and finally these simulations have been validated. These validations were carried out by means of two statistical techniques: by means of linear regression techniques and by means of a study of the significance (in an analysis of the variance) for the method used (sensors or CFD) in each different proposed validation model. Having validated these CFD results, CFD techniques can safely be used to characterise and analyse the ventilation in all the indoor space of the broiler buildings (sensors only allow it to be characterised in their physical locations). The first case studied involves a broiler building which has a cross mechanical ventilation system (commonplace in Mediterranean climates) installed. The conclusions from this study show that this ventilation system is adequate for broiler rearing during nearly the whole year in mild climatic locations (e.g. Mediterranean climate). However, on certain days or in periods of heat (summer), it would not be adequate because it cannot reach high enough air velocity values to reduce the heat stress on the broilers. The second case studied is a broiler building with tunnel mechanical ventilation installed. The conclusions from this study show that it is less suitable than the first one analysed (cross mechanical ventilation) for broiler rearing over nearly the whole year in mild climatic locations. However, on certain days or in periods of heat (summer), it is very suitable because it can reach higher air velocity values to reduce the heat stress on the broilers. The third case studied is a broiler building with single-sided mechanical ventilation installed. The conclusions from this study show that this ventilation system is suitable for broiler rearing almost throughout the year in mild climatic locations. However, on certain days or in periods of heat (summer), it would be not adequate because it cannot reach high enough air velocity values to reduce the heat stress. / [ES] La avicultura intensiva del pollo de carne (broiler) es un sector estratégico en la economía y desarrollo de muchos países y regiones, entre ellos España y la Comunidad Valenciana. La producción intensiva del broiler se da confinando al animal en edificios específicos (granjas de pollos) bajo un microclima interno controlado. Tiene dos variantes fundamentales en función de su sistema de ventilación: producción en granjas con ventilación natural y producción en granjas con ventilación mecánica (generalmente por depresión negativa mediante ventiladores de extracción). Un inadecuado diseño de la ventilación es la causa principal del estrés térmico y de la mortalidad de los pollos. En este sentido, una solución para disminuir el estrés térmico por calor y la mortalidad de los pollos es ayudar en su termorregulación biológica mediante un aumento de la velocidad del aire sobre ellos. En esta tesis doctoral, se ha caracterizado y analizado la ventilación (rangos de velocidad del aire y su distribución, especialmente al nivel de presencia del pollo) en los principales sistemas de ventilación mecánicos instalados en las granjas de pollos. Pese a la envergadura de la actual problemática (estrés térmico y mortalidad de los pollos) y la sensibilidad de la sociedad hacia los aspectos del bienestar animal, hasta la fecha no se han caracterizado y analizado con rigurosidad científica los diferentes sistemas de ventilación mecánicos en las diferentes tipologías de granjas de pollos. En esta tesis doctoral se han estudiado los tres más relevantes: cruzado, túnel y de pared única. El enfoque metodológico en todos los casos de estudio ha sido muy similar: se han realizado unas mediciones mediante un sistema multisensor de registro isotemporal (de diseño y fabricación propios), se han realizado las correspondientes simulaciones Computational Fluid Dynamics (CFD) y finalmente se han validado estas simulaciones. Estas validaciones se han llevado a cabo mediante dos técnicas estadísticas: mediante técnicas de regresión lineal y mediante el estudio de la significatividad (en un análisis de la varianza) de la metodología utilizada (sensores o CFD) en sendos modelos de validación propuestos. Una vez validadas estas simulaciones CFD, se tiene la seguridad de poder utilizarlas para caracterizar y analizar la ventilación en todo el espacio interior de las granjas (los sensores sólo permiten caracterizarla en las localizaciones físicas de los mismos). El primer caso de estudio es el de una granja que tiene instalado un sistema de ventilación mecánico cruzado (habitual en el clima Mediterráneo). Las conclusiones de este estudio demuestran que este sistema de ventilación es adecuado para la crianza del pollo para casi todo el año en localizaciones climáticas templadas (por ejemplo, el clima Mediterráneo). Sin embargo, en días o periodos de calor (verano), no será adecuado porque no se pueden alcanzar valores de velocidad del aire grandes que permiten disminuir el estrés por calor de los pollos. El segundo caso de estudio es el de una granja que instala el sistema de ventilación mecánico túnel. Las conclusiones de este estudio demuestran que es menos apropiado que el anterior (sistema de ventilación mecánico cruzado) para la crianza del pollo durante todo el año en localizaciones climáticas templadas. Sin embargo, en días o periodos de calor (verano), será muy adecuado porque se pueden alcanzar valores de velocidad del aire grandes que permiten disminuir el estrés por calor de los pollos. El tercer caso de estudio es el de una granja que instala el sistema de ventilación mecánico de pared única. Las conclusiones de este estudio demuestran que este sistema de ventilación es adecuado para la crianza del pollo para casi todo el año en localizaciones climáticas templadas. Sin embargo, en días o periodos de calor (verano), no será adecuado porque no se pueden alcanzar valores de ve / [CA] L'avicultura intensiva del pollastre de carn (broiler) és un sector estratègic en l'economia i desenvolupament de molts països i regions, entre ells Espanya i la Comunitat Valenciana. La producció intensiva del broiler es dóna confinant a l'animal en edificis específics (granges de pollastres) sota un microclima intern controlat. Té dues variants fonamentals en funció del seu sistema de ventilació: producció en granges amb ventilació natural i producció en granges amb ventilació mecànica (generalment per depressió negativa mitjançant ventiladors d'extracció). Un inadequat disseny de la ventilació és la causa principal de l'estrés tèrmic i de la mortalitat dels pollastres. En aquest sentit, una solució per disminuir l'estrés tèrmic per calor i la mortalitat dels pollastres és ajudar en la seua termoregulació biològica mitjançant un augment de la velocitat damunt d'ells. En aquesta tesi doctoral, s'ha caracteritzat i analitzat la ventilació (rangs de velocitat de l'aire i la seua distribució, especialment al nivell de presència del pollastre) en els principals sistemes de ventilació mecànics instal·lats a les granges de pollastres. Malgrat l'envergadura de l'actual problemàtica (estrés tèrmic i mortalitat dels pollastres) i la sensibilitat de la societat envers els aspectes del benestar animal, fins aquesta data no s'han caracteritzat i analitzat amb rigor científic els diferents sistemes de ventilació mecànics a les diferents tipologies de granges de pollastres. En aquesta tesi doctoral han sigut estudiats els tres més rellevants: creuat, túnel i de paret única. L'enfocament metodològic en tots els casos d'estudi ha sigut molt similar: han sigut realitzats uns mesuraments mitjançat us sistema multisensor de registre isotemporal (de disseny i fabricació propis), han sigut realitzades les corresponents simulacions Computational Fluid Dynamics (CFD) i finalment han sigut validades aquestes simulacions. Aquestes validacions s'han dut a terme mitjançant dues tècniques estadístiques: mitjançant tècniques de regressió lineal i mitjançant l'estudi de la significativitat (en una anàlisi de la variància) de la metodologia utilitzada (sensors o CFD) en sengles models de validació proposats. Una vegada validades aquestes simulacions CFD, es té la seguretat de poder utilitzar-les per a caracteritzar i analitzar la ventilació en tot l'espai interior de les granges (els sensors només permeten caracteritzar-la en les localitzacions físiques dels mateixos). El primer cas d'estudi és el d'una granja que té instal·lat un sistema de ventilació mecànic creuat (habitual en el clima Mediterrani). Les conclusions d'aquest estudi demostren que aquest sistema és adequat per a la criança del pollastre durant quasi tot l'any en localitzacions climàtiques moderades (per exemple, el clima Mediterrani). Tanmateix, en dies o períodes de calor (estiu), no serà adequat perquè no es poden obtenir valors de velocitat de l'aire grans que permeten disminuir l'estrés per calor dels pollastres. El segon cas d'estudi és el d'una granja que instal·la el sistema de ventilació mecànic túnel. Les conclusions d'aquest estudi demostren que és menys adequat que l'anterior (sistema de ventilació mecànic creuat) per a la criança del pollastre durant tot l'any en localitzacions climàtiques moderades. Tanmateix, en dies o períodes de calor (estiu), serà molt adequat perquè es poden obtenir valors de velocitat de l'aire grans que permeten disminuir l'estrés per calor dels pollastres. El tercer cas d'estudi és el d'una granja que instal·la el sistema de ventilació mecànic de paret única. Les conclusions d'aquest estudi demostren que aquest sistema és adequat per a la criança del pollastre durant quasi tot l'any en localitzacions climàtiques moderades. Tanmateix, en dies o períodes de calor (estiu), no serà adequat perquè no es poden obtenir valors de velocitat de l'aire grans que perme / Bustamante García, E. (2015). OPTIMIZACIÓN DE DISEÑO DE GRANJAS AVÍCOLAS DE POLLOS [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/59450 / Compendio

Background: Invasive mechanical ventilation is common in an intensive care unit. The nurse works closely with the patient and should strive for person-centred care in accordance with guidelines and directives. Aim: To review and synthesize qualitative research exploring adult patients' experiences of being treated with invasive mechanical ventilation in intensive care. Method: A structured literature review of qualitative research. Structured searches were conducted in the databases CINAHL and PubMed, resulting in 14 articles. The methodology of the included articles was reviewed using a structured instrument and the results of the articles were analyzed using an inductive thematic analysis. Result: Four main themes: ‘A different perception of reality’, ‘The perceived discomfort’, ‘Including thepatient’ and ‘The suffering patient’. All with associated sub-themes. Conclusion: The experiences of being treated with invasive mechanical ventilation are many and complex. The results illustrate the importance of person-centred care, which can play a crucial role in promoting good care and providing alternative communication for patients. The results can provide aknowledge base for nurses to be able to alleviate suffering that may occur during treatment of invasive mechanical ventilation.

Sleep is an essential component of optimal physiological and psychological functioning in humans. However, numerous studies have identified sleep deficits in patients within the critical care setting. Sleep deprivation has been shown to cause adverse effects including cardiovascular, respiratory, and endocrine variations, and altered psychological functioning such as cognitive dysfunction, decreased concentration, mood variability, and delirium. The critical care environment often contains stimuli that may be a causative factor in sleep alterations such as sleep deprivation, fragmentation or alterations in sleeping patterns. These environmental stimuli include noise, light, pain, discomfort, nursing care activities, medications, psychological stressors and underlying disease and have the capability to severely impact the quantity and quality of sleep in critically ill patients. The integrated research review identifies correlations between environmental stressors and sleep alterations in critically ill patients. Outcomes of interventions including earplugs and eye masks, behavior modification, complementary and alternative medicine and pharmacological considerations are examined. Additionally, implications for nursing education, research and practice are addressed. A current integrated research review incorporating nursing implications and alternative interventions could be significant to the provision of nursing care for the critically ill patient.

Submitted by Luis Guilherme Macena (guilhermelg2004@gmail.com) on 2013-07-05T17:39:56Z No. of bitstreams: 1 Maria Tereza Fonseca da Costa.pdf: 3605712 bytes, checksum: d115f31efe017f3b85af7f13d23776d3 (MD5) / Made available in DSpace on 2013-07-05T17:39:56Z (GMT). No. of bitstreams: 1 Maria Tereza Fonseca da Costa.pdf: 3605712 bytes, checksum: d115f31efe017f3b85af7f13d23776d3 (MD5) Previous issue date: 2011 / Fundação Oswaldo Cruz. Instituto Fernandes Figueira. Departamento de Ensino. Programa de Pós-Graduação em Saúde da Criança e da Mulher. Rio de Janeiro, RJ, Brasil / Internações hospitalares de crianças e adolescentesportadores de alguma condição crônica de saúde têm evoluído de modo crescente em diferentes países e também apresentam-se como uma situação de saúde que deve ser considerada no planejamento de ações e organização de serviços de saúde, no Brasil. O exemplo das internações por dependência crônica de ventilação pulmonar mecânica é apresentado no presente estudo,a partir da observação inicial de que constituem-se situações que determinam longa permanência hospitalar em leitos de alta complexidade, como nosde terapia intensiva pediátrica, sendo também alvo de solicitações através de sentenças judiciais para cobertura de assistência domiciliar ainda precariamente estabelecida no âmbito do sistema de saúde brasileiro. Há mais de três décadas que têm sido realizados estudos em outros países, na tentativa de ampliar-se o conhecimento sobre este problema de saúde, sendo analisados diferentes aspectos relacionados ao mesmo, como alternativas de locais seguros para cuidados em saúde oferecidos a estes pacientes crônicos e as diferenças de resultados médicos e sociais entre as alternativas possíveis. Com o objetivo de conhecer e analisar a ocupação de leitos de terapiaintensiva pediátrica por pacientes com dependência crônica de ventilação pulmonar mecânica, foi realizado um estudo seccional do tipo levantamento censitário de casos, de janeiro a março de 2011, em 29 hospitais públicos localizados na Cidade do Rio de Janeiro. O estudo permitiu identificar 31 pacientes de 0 a 18 anos, internados e em ventilação mecânica invasiva há 3 meses ou mais, em 10 dos 29 hospitais consultados. Nas unidades de terapia intensiva havia 14 internações justificadas por esse tipo de dependência tecnológica, caracterizando uma ocupação de 21% do total de leitos disponíveis de terapia intensiva, no período de estudo. O conhecimento desse quantitativo permite aprofundamento da discussão sobre aspectos éticos, técnicos e normativos que devem ser considerados no desenvolvimento de propostas à assistência de pacientes crônicos, visando a melhor relação entre investimentos e resultados, para os pacientes, seus familiares e a sociedade. / Children and adolescents with chronic health conditions hospitalizations are increasingly evolved in different countries and presented as a health situation that must be considered in planning and organizing action of health services in Brazil. The hospital chronic dependency on mechanical ventilation is an example presented in this study, from the initial observation situation which determining long stay high complexity hospital beds, as in the pediatric intensive care, is also the subject of requests through sentences legal coverage for home care, still precariously established within Brazilian health system. Studies in others countries to expand knowledge about this health problem had been for over three last decades, analyzing different aspects related as alternative safe places for health care offered tothese chronic patients and differences between medical and social results from possible alternatives. With the aim to understand and analyze the occupation ofpediatric intensive care beds with ventilator-dependent patients, a survey was realized from January to March, 2011, in 29 public hospitals located in the city of Rio de Janeiro. The study identified 31 patients from zero to 18 years,hospitalized and on invasive mechanical ventilation for 3 months or more, in 10 of the 29 investigated hospitals. In 14 stays in intensive care units werejustified for this type of technological dependency, characterizing a 21% rateoccupancy of total intensive care beds available, along the research period. Knowledge that quantitative conduct to in-depth discussion on ethical, technical and legal standards should be considered when developing proposals aimed assistance for chronic patients, seeking the best value between investments and outcomes for patients, their family and society.

O processo de envelhecimento promove mudanças morfológicas e fisiológicas em todo organismo, tornando-o frágil. Com o envelhecimento, o comprometimento anatômico e fisiológico do sistema respiratório pode promover alterações físicas e funcionais responsáveis por facilitar o surgimento da insuficiência respiratória, levando a internação em terapia intensiva e ventilação mecânica invasiva. Com objetivo de determinar quais variáveis estão associadas ao sucesso do desmame da ventilação mecânica em pacientes idosos e não idosos, foi delineada uma coorte retrospectiva com 331 pacientes, em três unidades de terapia intensiva do Hospital de Clínicas Niterói, Rio de Janeiro, Brasil. A prevalência de sucesso no desmame na amostra foi de 83,7%. Os resultados após análise multivariada demonstraram como variáveis independentes associadas ao desmame na amostra total e nos pacientes com idade < 70 anos o APACHE II e o índice integrativo de desmame (IWI). Nos pacientes com idade > 70 anos, o IWI foi a única variável respiratória independente encontrada para melhor prognóstico do desmame. O presente estudo concluiu que não houve influência da idade no resultado do desmame e o IWI demonstrou ser a principal variável preditora do desmame na população de pacientes idosos. / The ageing promotes morphological and physiological changes throughout the body, making it fragile. With ageing, the physiological and anatomical impairments of the respiratory system may promote physical and functional changes responsible for facilitating the development of respiratory failure, resulting in stays in intensive care and invasive mechanical ventilation. In order to determine which variables were associated to the successful weaning from mechanical ventilation in elderly and non-elderly patients, we evaluated 331 patients through a retrospective cohort in three intensive care units of the Hospital de Clínicas Niterói, Rio de Janeiro, Brazil. The Prevalence of the successful weaning in the entire sample evaluated was 83.7%. The results, after multivariate analysis, showed as independent variables associated with weaning in total sample and in patients aged < 70 years old, APACHE II and Integrative weaning índex (IWI). In patients aged > 70 years old, IWI was the single independent respiratory variable found related to the successful weaning. In conclusion, age presented no influence on weaning outcome. The IWI showed to be the main variable of weaning outcome in elderly patients.

O processo de envelhecimento promove mudanças morfológicas e fisiológicas em todo organismo, tornando-o frágil. Com o envelhecimento, o comprometimento anatômico e fisiológico do sistema respiratório pode promover alterações físicas e funcionais responsáveis por facilitar o surgimento da insuficiência respiratória, levando a internação em terapia intensiva e ventilação mecânica invasiva. Com objetivo de determinar quais variáveis estão associadas ao sucesso do desmame da ventilação mecânica em pacientes idosos e não idosos, foi delineada uma coorte retrospectiva com 331 pacientes, em três unidades de terapia intensiva do Hospital de Clínicas Niterói, Rio de Janeiro, Brasil. A prevalência de sucesso no desmame na amostra foi de 83,7%. Os resultados após análise multivariada demonstraram como variáveis independentes associadas ao desmame na amostra total e nos pacientes com idade < 70 anos o APACHE II e o índice integrativo de desmame (IWI). Nos pacientes com idade > 70 anos, o IWI foi a única variável respiratória independente encontrada para melhor prognóstico do desmame. O presente estudo concluiu que não houve influência da idade no resultado do desmame e o IWI demonstrou ser a principal variável preditora do desmame na população de pacientes idosos. / The ageing promotes morphological and physiological changes throughout the body, making it fragile. With ageing, the physiological and anatomical impairments of the respiratory system may promote physical and functional changes responsible for facilitating the development of respiratory failure, resulting in stays in intensive care and invasive mechanical ventilation. In order to determine which variables were associated to the successful weaning from mechanical ventilation in elderly and non-elderly patients, we evaluated 331 patients through a retrospective cohort in three intensive care units of the Hospital de Clínicas Niterói, Rio de Janeiro, Brazil. The Prevalence of the successful weaning in the entire sample evaluated was 83.7%. The results, after multivariate analysis, showed as independent variables associated with weaning in total sample and in patients aged < 70 years old, APACHE II and Integrative weaning índex (IWI). In patients aged > 70 years old, IWI was the single independent respiratory variable found related to the successful weaning. In conclusion, age presented no influence on weaning outcome. The IWI showed to be the main variable of weaning outcome in elderly patients.

Des asynchronies patient-ventilateur sont fréquemment observées en ventilation assistée. Objectif : Déterminer l'incidence et les facteurs favorisants des asynchronies, venant du patient, du ventilateur ou des réglages, et préciser le réglage optimal du ventilateur. Méthodes : Nous avons évalué l'incidence des asynchronies avec une méthode simple et non invasive basée sur l'analyse des courbes du ventilateur. Chez les patients qui présentaient des efforts inefficaces, nous avons mesuré l'effort inspiratoire avec une sonde œsophagienne afin d'optimiser le réglage du ventilateur. Nous avons évalué l'impact du mode ventilatoire sur la qualité du sommeil avec une polysomnographie complète. Enfin, tous les ventilateurs de réanimation ont été testés sur banc afin de comparer les performances en termes de trigger et pressurisation. Résultats : Près d'un quart des patients présentaient des asynchronies fréquentes. La durée de ventilation de ces patients était plus longue et le sevrage plus difficile. Les efforts inefficaces, qui représentaient les asynchronies les plus fréquentes, étaient favorisés par une assistance ventilatoire excessive. La réduction du niveau d'aide inspiratoire (AI) permettait d'éliminer quasi-complètement les efforts inefficaces, sans augmenter l'effort inspiratoire et sans modifier la vraie fréquence respiratoire du patient. Le mode ventilatoire n'avait pas d'influence sur la qualité du sommeil et les asynchronies. Les efforts inefficaces survenaient aussi bien en AI qu'en ventilation assistée contrôlée. Avec un niveau d'AI adéquat, les apnées centrales étaient peu nombreuses et n'avaient pas d'influence sur la qualité du sommeil. Les performances insuffisantes observées avec certains ventilateurs peuvent également altérer la synchronisation. Conclusion : Les asynchronies patient-ventilateur sont fréquentes et associées à une durée de ventilation prolongée. Une « dose de ventilation » excessive favorise les efforts inefficaces, mais un réglage optimal du ventilateur permet de minimiser ces asynchronies. Cette thèse est un support pour déterminer dans une étude plus large si une synchronisation adéquate peut réduire la durée de ventilation. / Major patient-ventilator asynchrony seems common on ventilator screen during assisted mechanical ventilation. Objectives: To evaluate the incidence of major asynchrony and to identify factors related to patient's characteristics and ventilator parameters associated with asynchrony, and to determine optimal ventilator adjustments. Methods: We evaluated the incidence of major patterns of asynchrony easily detected using a noninvasive method based on flow and airway pressure curves. In patients with frequent ineffective efforts we measured patient's effort using esophageal pressure measurements to optimize ventilatory settings. We evaluated the impact of ventilatory mode on sleep quality using a complete polysomnography. All intensive-care-unit ventilators were compared on a bench test in terms of trigger performance and pressurization capacity. Results: One-fourth of intubated patients exhibited major asynchrony. Duration of mechanical ventilation was longer and weaning more difficult in patients with asynchrony as compared to patients without asynchrony. Ineffective triggering was the main pattern of asynchrony and was promoted by excessive ventilatory assistance. Reducing the pressure-support completely eliminated ineffective efforts in most of patients, without inducing excessive respiratory muscle effort and without modifying the true patient's respiratory rate. Ventilatory mode did not influence sleep quality and asynchrony. Ineffective efforts were detected during both pressure-support ventilation and assist-control ventilation, and central apneas were not common using adequate level of pressure-support. Some ventilators exhibited poor performances which could promote patient-ventilator asynchrony. Conclusion: Patient-ventilator asynchrony is frequent during assisted ventilation and associated with prolonged duration of mechanical ventilation. Excessive ventilatory support could promote ineffective efforts although optimal ventilatory settings could minimize asynchrony. This work is a starting point to determine in a large study, whether optimization of ventilatory settings could shorten duration of mechanical ventilation.