The goal of lung-protective mechanical ventilation is to provide life-sustaining support of gas exchange while minimizing the risk of ventilator-induced lung injury. Multi-frequency oscillatory ventilation (MFOV) was proposed as an alternative lung-protective modality, in which multiple frequencies of pressure and flow oscillations are delivered simultaneously at the airway opening and allowed to distribute throughout the lung in accordance with regional mechanical properties. The distribution of oscillatory flow is frequency-dependent, such that regions overventilated at one frequency may be underventilated at another. Thus the central thesis of this work was that ventilation heterogeneity is frequency-dependent, and therefore ventilation with multiple simultaneous frequencies can be optimized to reduce the risk of ventilator-induced lung injury. Simulations in computational models of distributed oscillatory flow and gas transport demonstrated the sensitivity of regional ventilation heterogeneity to subject size, ventilation frequency, and injury severity. Although the risk of injury in the model associated with strain or strain rate individually was minimized by single-frequency ventilation, the risk of injury associated with mechanical power in lung parenchymal tissue was minimized by MFOV. In an experimental model of acute lung injury, MFOV was associated with reductions in the magnitude and spatial gradient of regional lung strain estimated by four-dimensional CT image registration, as well as increased rates of regional gas transport estimated by wash-in of xenon tracer gas. In conclusion, computational models demonstrated the potential for optimization of MFOV waveforms, and experimental trials demonstrated evidence of improved regional ventilation during MFOV.

<p>Muntlig kommunikation kan vara begränsad eller omöjlig när patienten är intuberad vid respiratorbehandling. Intuberingen hindrar talet och detta kan vara frustrerande för många patienter. Syftet med studien var att belysa hur intuberade intensivvårdspatienter upplever kommunikation. För att genomföra studien valdes systematisk litteraturstudie som metod. Resultatet baseras på 11 artiklar. I resultatet framträdde tre kategorier: negativa upplevelser, positiva upplevelser och patienters upplevelser av omgivande faktorers påverkan. Bland negativa upplevelser är frustration/ångest vanligt. Att inte bli förstådd skapar en stor känsla av beroende. Bekräftelse är en positiv upplevelse för patienterna, vilket kan uppnås bland annat av att patientens lidande uppmärksammas. Bland omgivande faktorers påverkan spelar hjälpmedel, intensivvårdspersonal och familj/anhöriga en stor roll. För att förbättra intuberade patienters möjligheter till kommunikation skulle fortsatt forskning om hur olika hjälpmedel påverkar patienterna vara intressant.</p> / <p>Verbal communication may be limited or impossible when the patient is intubated for mechanical ventilation. Intubation obstructs the speech and can be frustrating for patient. The aim of this study was to elucidate how intubated intensive care patients experience communication. A systematic literature review was chosen to implement the study. The results are based on 11 articles. Three categories emerged and materialized in the results: <em>Negative emotions</em>, <em>Positive emotions</em> and <em>Patients experiences of the influence of ambient factors</em>. Frustration and anxiety are common among the negative emotions. Not to be understood creates a great sense of dependency. Confirmation is a positive feeling for the patients, which can be achieved, among other things, by acknowledging the patients discomfort. Augmentative aids, the intensive care environment and staff in the intensive care unit are important components that play an important role of ambient factors category. Further research on how to improve intubated patients opportunities for communication with different augmentative aids would be interesting.</p>

Bakgrund: Många av patienterna på en neurointensivvårdsavdelning (NIVA) vårdas med respirator under en längre eller kortare period av vårdtiden. Neurointensivvårdspatienterna bedöms ibland utifrån de kriterier för urträning och extubering som används på allmänna intensivvårdspatienter. Detta kan leda till för tidig extubation med reintubation som följd. Syfte: Redogöra för vilka kriterier som ska bedömas hos neurointensivvårdspatienter inför en extubering. Metod: Litteraturstudie. Resultat och slutsats: Neurointensivvårdspatienter behöver uppfylla en kombination av kriterier inför extubation. Hänsyn ska tas till de generella extubationskriterierna avseende andning och cirkulation. Dessutom ska patienten ha en tillräckligt hög medvetandegrad för att kunna följa någon form av uppmaning. Till sist ska patientens förmåga att hålla fri luftväg bedömas genom observation av hostkraft, sekretmängd/konsistens och svalgfunktion. Det behövs ytterligare forskning för att utröna i hur hög grad neurointensivvårdspatienterna behöver vara medvetna inför extubering och på vilket sätt detta bäst bedöms. Forskning behövs kring ett enhetligt tillvägagångssätt för bedömning av hostkraft, sekretmängd/konsistens och svalgfunktion. / Background: Many of the patients cared for in a neurocritical unit are treated with mechanical ventilation for a longer or shorter period of time during their stay in the unit. When weaning or extubating neurocritical patients, they are sometimes assessed according to the criteria for weaning and extubation used in general intensive care patients. This can cause premature extubation, resulting in re-intubation. Aim: Describe the criteria to be assessed in neurocritical patients prior to extubation. Method: Literature review. Results and conclusion: Neurocritical patients need to fulfil a combination of criteria prior to extubation. The general criteria in terms of respiration and circulation must be taken in to consideration, as well as the patient’s level of consciousness. The patient has to be conscious enough to be able to take directions. Lastly the patient’s ability to protect the airway must be assessed by observation of cough strength, the quantities and viscosity of the secretions and the patient’s swallowing function. Further research is required to ascertain the level of consciousness required in the neurocritical patients prior to extubation and in which way the assessment is best carried out. There is also need for further research considering a standardized measurement for assessing cough strength, the quantities and viscosity of secretions and swallowing function in these patients.

Muntlig kommunikation kan vara begränsad eller omöjlig när patienten är intuberad vid respiratorbehandling. Intuberingen hindrar talet och detta kan vara frustrerande för många patienter. Syftet med studien var att belysa hur intuberade intensivvårdspatienter upplever kommunikation. För att genomföra studien valdes systematisk litteraturstudie som metod. Resultatet baseras på 11 artiklar. I resultatet framträdde tre kategorier: negativa upplevelser, positiva upplevelser och patienters upplevelser av omgivande faktorers påverkan. Bland negativa upplevelser är frustration/ångest vanligt. Att inte bli förstådd skapar en stor känsla av beroende. Bekräftelse är en positiv upplevelse för patienterna, vilket kan uppnås bland annat av att patientens lidande uppmärksammas. Bland omgivande faktorers påverkan spelar hjälpmedel, intensivvårdspersonal och familj/anhöriga en stor roll. För att förbättra intuberade patienters möjligheter till kommunikation skulle fortsatt forskning om hur olika hjälpmedel påverkar patienterna vara intressant. / Verbal communication may be limited or impossible when the patient is intubated for mechanical ventilation. Intubation obstructs the speech and can be frustrating for patient. The aim of this study was to elucidate how intubated intensive care patients experience communication. A systematic literature review was chosen to implement the study. The results are based on 11 articles. Three categories emerged and materialized in the results: Negative emotions, Positive emotions and Patients experiences of the influence of ambient factors. Frustration and anxiety are common among the negative emotions. Not to be understood creates a great sense of dependency. Confirmation is a positive feeling for the patients, which can be achieved, among other things, by acknowledging the patients discomfort. Augmentative aids, the intensive care environment and staff in the intensive care unit are important components that play an important role of ambient factors category. Further research on how to improve intubated patients opportunities for communication with different augmentative aids would be interesting.

The transition from mechanical ventilation (MV) to spontaneous ventilation during weaning is associated with hemodynamic alterations and autonomic nervous system (ANS) alterations (reflected by heart rate variability [HRV]). Although cardiac dysrhythmias are an important manifestation of hemodynamic alterations, development of dysrhythmias during MV and weaning and subsequent impact on length of MV has received little attention. The purposes of this dissertation were to 1) evaluate the relationship of heart rate variability (HRV) during weaning to the development of cardiac dysrhythmias and 2) determine the relationship of cardiac dysrhythmias to length of MV. A convenience sample of 35 patients (66.7% men; mean age 53.3 years) who required MV was enrolled in this study. Continuous 3-lead electrocardiographic data were collected for 24 hours at baseline during MV and for the first 2 hours during the initial weaning trial. HRV was evaluated using spectral power analysis. Twenty- seven patients out of 30 were exposed to a combination of pressure support (8-15 cm H2O) and continuous positive airway pressure 5 cm H2O during weaning trial. Three patients self- extubated and received supplemental oxygen through either a partial rebreathing or non-rebreathing mask. Low frequency (LF) power HRV decreased, while high frequency (HF) and very low frequency (VLF) power HRV did not change during weaning. Multiple regression analyses showed that LF and HF HRV were significant predictors of occurrence of ventricular and supraventricular ectopic beats during weaning, while VLF power predicted occurrence of ventricular ectopic beats only. The mean of occurrence of supraventricular ectopic beats per hour during weaning was double the mean at baseline, while the mean of ventricular ectopic beats per hour did not change. Mean number of supraventricular ectopic beats per hour during weaning was a significant predictor of length of MV. This dissertation has fulfilled an important gap in the evidence base for cardiac dysrhythmias during weaning from MV. Cardiac dysrhythmias and HRV alterations should be systemically evaluated during MV and weaning trials in order to decrease length of MV.

Bakgrund: För tidig eller för sen urträning från ventilator kan ge negativa konsekvenser för patienten, därför bör det identifieras när patientens tillstånd tillåter detta. Med anledning av det och att ansvaret för urträningen övergått mer från läkarna till sjuksköterskorna har det utvecklats hjälpmedel såsom evidensbaserade urträningsprotokoll. Dessa medför en mer samstämmig behandling och har också visat sig leda till kortare behandlingstid med ventilator. Olikheter i vårdpersonalens kunskap, utbildningsnivå, erfarenhet, ansvarsområden och hur organisationen ser ut påverkar hur urträningen genomförs.  Syfte: Att beskriva intensivvårdssjuksköterskors uppfattning om urträning från ventilator. Metod: En empirisk fokusgruppintervjustudie med kvalitativ och deskriptiv ansats genomfördes. Antal deltagare var sex intensivvårdssjuksköterskor. Datamaterialet analyserades med kvalitativ innehållsanalys. Resultat: Det framkom tre huvudkategorier, Organisationen, Intensivvårdssjuksköterskan och Patienten samt fyra subkategorier, Rutiner, Samarbete, Kompetens och Omvårdnad. Slutsats: Det behövs en tydlig struktur i organisationen för att urträningsprocessen ska fungera tillfredsställande. Denna struktur kan skapas med rutiner, fungerande samarbete, tydlig kommunikation och hjälpmedel så som urträningsprotokoll. Urträningen för patienterna skulle underlättas, bli mer effektiv och leda till kortare behandlingstid. Klinisk betydelse: Studien kan bidra till diskussion om vilka förutsättningar som behövs för att bedriva en effektiv urträning utifrån god och säker evidensbaserad vård. Dessa förutsättningar kan bidra till ökad patientsäkerhet, kortare vårdtid och lägre vårdkostnader. / Background: Weaning onset should be initiated when the patient´s condition permits it, too early or late onset can have negative consequences for the patient. To help the nurse perform weaning, tools such as evidence-based weaning protocols have been developed and results in more consistent treatment shown to shortening duration of ventilator treatment. Differences between health profession, i.e. educational level, experience, responsibilities and organization structure, affect how the weaning is performed. Objective: To describe ICU nurses´ perception of ventilator weaning. Method: An empirical focus group study with a qualitative and descriptive approach was conducted. Six intensive care nurses were included. Data was analyzed using content analysis. Results: Three main categories were revealed, the Organization, the Intensive care nurse and the Patient along with four subcategories, Procedures, Collaboration, Competence and Nursing. Conclusion: For the weaning process to work satisfactorily a clear structure is needed. This can be created with routines, effective collaboration, clear communication and tools such as weaning protocols. For the patients weaning would be facilitated, become more efficient and shorten the duration of treatment. Clinical significance: The study may contribute to the discussion about the conditions needed to conduct effective weaning based on good and reliable evidence-based care. These conditions may contribute to increase patient safety, shorter hospital stay and lower health care costs.

Acute quadriplegic myopathy (AQM), or critical illness myopathy, is a common debilitating acquired disorder in critically ill intensive care unit (ICU) patients characterized by generalized muscle wasting and weakness of limb and trunk muscles. A preferential loss of the thick filament protein myosin is considered pathognomonic of this disorder, but the myosin loss is observed relatively late during the disease progression. In attempt to explore the potential role of factors considered triggering AQM in sedated mechanically ventilated (MV) ICU patients, we have studied the early effects, prior to the myosin loss, of neuromuscular blockade (NMB), corticosteroids (CS) and sepsis separate or in combination in a porcine experimental ICU model. Specific interest has been focused on skeletal muscle gene/protein expression and regulation of muscle contraction at the muscle fiber level. This project aims at improving our understanding of the molecular mechanisms underlying muscle specific differences in response to the ICU intervention and the role played by the different triggering factors. The sparing of masticatory muscle fiber function was coupled to an up-regulation of heat shock protein genes and down-regulation of myostatin are suggested to be key factors in the relative sparing of masticatory muscles. Up-regulation of chemokine activity genes and down-regulation of heat shock protein genes play a significant role in the limb muscle dysfunction associated with sepsis. The effects of corticosteroids in the development of limb muscle weakness reveals up-regulation of kinase activity and transcriptional regulation genes and the down-regulation of heat shock protein, sarcomeric, cytoskeletal and oxidative stress responsive genes. In contrast to limb and craniofacial muscles, the respiratory diaphragm muscle responded differently to the different triggering factors. MV itself appears to play a major role for the diaphragm muscle dysfunction. By targeting these genes, future experiments can give an insight into the development of innovative treatments expected at protecting muscle mass and function in critically ill ICU patients.

Made available in DSpace on 2014-06-11T19:23:32Z (GMT). No. of bitstreams: 0 Previous issue date: 2008-02-29Bitstream added on 2014-06-13T20:30:20Z : No. of bitstreams: 1 danaga_ar_me_botfm.pdf: 251409 bytes, checksum: a7b3e3680e2f319a5c5122c4c8575ff0 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / A ventilação mecânica invasiva é recurso fundamental em unidades de terapia intensiva. Sua aplicação ocorre em quase metade dos pacientes dessas unidades. Entretanto, a VMI associa-se a várias complicações, especialmente quando utilizada por período prolongado. Desse modo, preconiza-se que a interrupção do suporte ventilatório seja realizada assim que possível. A intempestividade em realizar tanto o desmame como a extubação pode gerar graves conseqüências ao paciente, incluindo a necessidade de reintubação. Esta, por sua vez, está relacionada à elevada incidência de pneumonia hospitalar, o que leva ao maior tempo de ventilação mecânica, de permanência na terapia intensiva, aumento no custo hospitalar e da mortalidade. Visto que tanto a ventilação mecânica prolongada como sua retirada prematura podem ser prejudiciais, faz-se necessário o reconhecimento do momento ideal do desmame e extubação. Vários índices fisiológicos foram propostos com o intuito de identificar os pacientes capazes de reassumir a ventilação espontânea. Poucos ofereceram poder preditivo satisfatório e o índice de respiração rápida e superficial parece ser o mais útil devido sua simplicidade e confiabilidade. No entanto, o melhor ponto de corte dos índices fisiológicos raramente foi estabelecido por curva ROC, evidenciando a necessidade de novos estudos. Neste trabalho, foram revisados os estudos que demonstraram a importância da utilização de protocolos de desmame e extubação e avaliaram o papel preditivo dos índices propostos. / Invasive mechanical ventilation is crucial in intensive care units and its application becomes necessary in almost half of the patients. However it has been associated to several complications especially under prolonged use. Therefore it is reccomended that the discontinuation of ventilator support must be attemped as soon as possible. The premature weaning or extubation also can gerate negative consequences to the patient, including the need of reintubation. This is most related to higher incidence of nosocomial pneumonia, increased IMV use and ICU length of stay, hospital costs and elevated mortality rates. Because of both, prolonged IMV and it’s premature discontinuation can be harmful, it is necessary to recognize the optimal moment for weaning and extubation. Many physiological indexes were proposed to distinguish patients ready to breath spontaneously, but fewness demonstrated satisfatory predictive power. Rapid shallow breathing index seems to be the most useful parameter because of its simplicity and reliability. However, in rare studies the best threshold for these indexes was established by ROC curve, making evident the need of further investigations. The present study reviewed articles that demonstrated importance of weaning and extubation protocols utilization and that assessed the predictive role of physiological indexes.

Made available in DSpace on 2015-05-14T12:47:19Z (GMT). No. of bitstreams: 1 arquivototal.pdf: 3269699 bytes, checksum: af9285a2857f32a228efc8a34c2c80c4 (MD5) Previous issue date: 2014-08-29 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Of critically ill patients in intensive care units (ICUs), about 40% develop acute respiratory failure (ARF) requiring invasive mechanical ventilation (IMV), which should be conducted as soon as possible for weaning, which may be defined as the process of transition from mechanical ventilation to spontaneous in patients who remain at MVI for more than 24 hours time. To consider that they had successfully weaned, the patient must maintain spontaneous ventilation for at least 48 hours after discontinuation of artificial ventilation. However, if the return to ventilatory support is needed in this period of 48 hours after extubation, called unsuccessful weaning. In clinical practice, patients are subjected to interruption of MVI, the passage through the spontaneous breathing trial (SBT) is recommended, achieving tolerate 30 minutes disconnected from ventilatory support without important clinical changes. The SBT is recommended as a diagnostic test to bring greater security to taking the patient off the machine decision. Although recommended, it is important to note that in studies, this test has not been shown to be accurate, not identified approximately 15% of weaning failure. The aim of this study is to propose a model to predict the success of weaning from mechanical ventilation to assist decision making for weaning in patients admitted to the Intensive Care Unit. This is an observational, longitudinal, prospective, quantitative and descriptive. 24 hours after the institution of MVI at the time prior to the SBT and the team after the withdrawal of MVI until the occurrence of the outcome of weaning success or failure: an instrument for data collection, divided into four periods was used. The statistical method of logistic regression was used to support decision making from clinical variables collected in the study. The clinical variables that were statistically significant (p-value <0.05) were: Tobin index between 51 and 105 (OR = 79.3); Sodium levels between 135 and 14 (OR = 20.3) and balances the Hydraulic balanced (OR = 9.6). The findings of this study present a valid logistic model, revealing the clinical variables that correlate with the success of weaning from invasive mechanical ventilation, thereby guiding decision making in this context. / Dos pacientes graves internados em unidades de terapia intensiva (UTI s), cerca de 40%, desenvolvem insuficiência respiratória aguda (IRpA), necessitando de ventilação mecânica invasiva (VMI), a qual deve ser conduzida tão logo seja possível para o desmame, definido como o processo de transição da ventilação artificial para a espontânea nos pacientes que permanecem em VMI por tempo superior a 24 horas. Para considerar que houve sucesso no desmame, o paciente deve manter a ventilação espontânea durante pelo menos 48 horas após a interrupção da ventilação artificial. No entanto, se o retorno ao suporte ventilatório for necessário neste período de 48hs pós-extubação, denomina-se insucesso do desmame. Na prática clínica, para que os pacientes sejam submetidos à interrupção da VMI, recomenda-se a passagem pelo teste de respiração espontânea (TRE), conseguindo tolerar 30 minutos desconectados do suporte ventilatório, sem apresentar alterações clínicas importantes. O TRE é recomendado como um teste diagnóstico para trazer maior segurança à tomada de decisão da desconexão do paciente à máquina. Embora recomendado, é importante ressaltar que, nos estudos, esse teste não tem se mostrado acurado, não identificando aproximadamente 15% das falhas de desmame. O objetivo deste estudo foi propor um modelo para predizer o sucesso do desmame da ventilação mecânica invasiva, para auxiliar a tomada de decisão para o desmame em pacientes internados na unidade de terapia intensiva. Trata-se de um estudo observacional, longitudinal, prospectivo, quantitativo e descritivo. Foi utilizado um instrumento de coleta de dados, dividido em quatro momentos: apos 24 horas da instituição da VMI, no momento antes da realização do TRE pela equipe e após a retirada da VMI ate a ocorrência do desfecho sucesso ou insucesso do desmame. O método estatístico de regressão logística foi usado para subsidiar a tomada de decisão a partir das variáveis clínicas coletadas no estudo. As variáveis que apresentaram significância estatística (p-valor < 0,05) foram: índice de Tobin entre 50 e 105 irpm/L (OR= 79,3); nível de sódio entre 135 e 145 mEq/L (OR=20,3) e balanço hídrico equilibrado (OR = 9,6). Os achados deste estudo possibilitaram a construção de um modelo logístico válido, revelando as variáveis clínicas que se correlacionaram com o sucesso do desmame da ventilação mecânica invasiva, orientando, assim, a tomada de decisão neste contexto.

A utilização de ventilação mecânica em terapia intensiva é uma prática comum. Além da sua ação terapêutica, é aplicada para corrigir os efeitos depressores consequentes da ação dos fármacos em pacientes sob sedoanalgesia. Por isso, vem sendo estudada para uma melhor compreensão da sua função, principalmente no que diz respeito às diferentes concentrações de oxigênio e as modalidades ventilação controlada a volume (VCV) e ventilação controlada a pressão (VCP) que podem desencadear diferentes respostas dos indivíduos. O objetivo deste trabalho é realizar um estudo comparativo da dinâmica cardiorrespiratória de suínos (Sus scrofa domestica) sedados com propofol-remifentanil sob dois aspectos: avaliar os animais submetidos a três diferentes frações inspiradas de oxigênio (FIO2) (0.8, 0.6, e 0.4) sob ventilação mecânica; avaliar e comparar os animais submetidos à VCV versus os submetidos à VCP. Utilizou-se 20 animais para realizar o comparativo entre as frações inspiradas e destes, seis para o comparativo entre as modalidades ventilatórias. Para sedação receberam em média 0,29 mg.kg-1.min-1 de propofol e 0,3 mcg.kg-1.min-1 de remifentanil, sendo que a velocidade de infusão de propofol variou buscando manter o animal em uma escala de consciência baseada no índice biespectral entre 60 e 70. Na comparação entre as FIs os animais ficaram sedados por duas horas e na comparação entre VCP e VCV, duas horas em cada modalidade. Foram avaliadas as frequências cardíaca e respiratória, eletrocardiografia, saturação de oxigênio em hemoglobina, pressão arterial, fração de dióxido de carbono no final da expiração, ventilometria e a hemogasometria. Com a obtenção de resultados percebeu-se uma vantagem na utilização da FIO2 0.4, pois apresenta menor porcentagem de shunt pulmonar, mas não ao ponto de descartar a utilização das outras FIs. No estudo comparativo VCV versus VCP não se encontrou diferenças. Durante a experimentação o protocolo empregado demonstrou ser adequado, pois causa mínimas alterações hemodinâmicas nos pacientes, proporcionando rápido e tranquilo despertar dos animais. Vale ressaltar que durante toda a experimentação os parâmetros se mantiveram constantemente dentro do aceitável para a espécie, o que permite indicar a técnica para futuros estudos. Com relação às diferentes FIs para a ventilação mecânica, utilizando-se oxigênio 40% teremos menos efeitos adversos. / The use of mechanical ventilation in intensive care is a common practice. In addition to therapeutic action it is applied to correct the depressant effects resulting from the action of drugs in patients under sedoanalgesia. Thus it is being studied for better understanding, especially with regard to different concentrations of oxygen and ventilatory volume (VCV) and pressure controlled (PCV) which can trigger different responses from each individual. The aim of this paper is a comparative study of cardiorespiratory dynamics of swine (Sus scrofa domestica) sedated with propofol-remifentanil in two ways: to evaluate the animals subjected to three different fractions of inspired oxygen (FIO2) (0.8, 0.6 and 0.4) mechanical ventilation; evaluate and compare the animals receiving VCV versus those submitted to the VCP. 20 animals were used to make the comparison between fractions of inspired oxygen and six for the comparison between both ventilatory modes. For sedation the animals received an average of 0,29 mg.kg-1.min-1 propofol and 0.3 mcg.kg-1.min-1 remifentanil, and the rate of propofol infusion varied in order to maintain the animal in a scale of consciousness based on the bispectral index between 60 and 70. Comparing the FIs the animals were sedated for two hours and the comparison between VCP and VCV, two hours in each mode. There were evaluated heart and respiratory rates, ECG, oxygen saturation of hemoglobin, blood pressure, fraction of carbon dioxide in end-tidal gas analysis and respirometry. With the achievement of results it was observed apparent advantage in using the FIO2 0.4, because it had a lower percentage of pulmonary shunt, but not to the point of discarding the use of other FIs. In the comparative study VCP versus VCV there were no differences. During the trial the protocol employed proved to be appropriate, because it causes minimal hemodynamic changes in patients, providing a quick and quiet awakening of the animals. It is noteworthy that throughout the experiment parameters were kept constant within the acceptable levels for the species, which can be indicated the technique for future studies. For the mechanical ventilation the best FI used was oxygen 40%, because it has fewer adverse effects.