No description available.

Early extubation of cardiac surgery patients has become increasingly important. The assessment of the patient before an early extubation is crucial and the intensive care nurses (ICU nurses) in this estimation is there for very important. The aim of this study was to examine critical care nurses' knowledge of early extubation, and what view ICU nurse has about factors that affect the time to extubation of cardiac surgery patients. A quantitative approach with descriptive and comparative design was used. Selection was all ICU nurses at a thoracic intensive care unit who were clinically active in patient care. The study showed that ICU nurses had good knowledge of why an early extubation was essential. However, the knowledge about the unit’s extubation criteria was low. ICU nurses felt that the criteria for the cardiac surgery patients on the unit was adequate. The time target of 90 minutes was reasonable. No relationship existed between professional experience and knowledge of the extubation criteria or between knowledge of the criteria and need of support from colleagues in early extubation of the cardiac surgery patients. The ICU nurses considered themselves familiar with the unit’s extubation criteria but the knowledge of them was low and the majority was working according to their own criteria. The units criteria was not sufficiently visible in the unit and could contributed to the low level of knowledge and contribute to that the majority of the ICU nurses was working according to their own criteria. / Tidig extubering av hjärtkirurgipatienter har blivit allt mer viktigt, en åtgärd där intensivvårdssjuksköterskan har en viktig roll i dennes bedömning av patienten. Syftet med studien var att belysa intensivvårdssjuksköterskans kunskap om tidig extubering samt vilken syn intensivvårdssjuksköterskan har på faktorer som påverkar tiden till extubering av hjärtkirurgipatienter. Studien har en kvantitativ ansats med deskriptiv och jämförande design. Metoden som användes var en enkätundersökning. Urvalet var alla intensivvårdssjuksköterskor på en thoraxintensivvårdsavdelning som var kliniskt verksamma i patientvården. Studien visade att intensivvårdssjuksköterskor hade bra kunskap om varför en tidig extubering eftersträvas. Däremot var kunskapen låg om avdelningens extuberingskriterier. Intensivvårds-sjuksköterskorna ansåg att kriterierna för hjärtkirurgipatienterna på avdelningen var tillräck-liga och att tidsmålet på 90 minuter var rimligt. Studien visade att inget samband fanns mellan yrkeserfarenhet och kunskap om extuberingskriterierna eller mellan kunskap om kriterierna och behov av stöd av kollegor vid tidig extubering av hjärtkirurgipatienter. Intensivvårdssjuksköterskorna ansåg sig känna till avdelningens extuberingskriterier men kunskapen om avdelningens extuberingskriterier var låg och majoriteten arbetar enligt sina egna kriterier. Avdelningens extuberingskriterier var inte tillräckligt synliga på avdelningen vilket kan bidra till den låga kunskapen och bidra till att majoriteten arbetade efter egna kriterier.

No description available.

Myocardial ischemia is a major cause of postoperative heart failure and adverse outcome in coronary artery bypass graft surgery (CABG). Conventional treatment of postoperative heart failure with inotropic drugs may aggravate underlying ischemic injury. Glutamate has been claimed to increase myocardial tolerance to ischemia and promote metabolic and hemodynamic recovery after ischemia. The aim of this work was to investigate if intravenous glutamate infusion given in association with CABG for acute coronary syndrome can reduce mortality and prevent or mitigate myocardial injury and postoperative heart failure. We also wanted to assess neurological safety issues, as a concern with the use of glutamate is that it may act as an excitotoxin under certain conditions.A metabolic strategy for perioperative care was assessed in an observational study on 104 consecutive patients with severe left ventricular dysfunction undergoing CABG. Based on encouraging clinical results, unsurpassed in the literature, the GLUTAMICS-trial was initiated. 861 patients undergoing CABG for acute coronary syndrome were randomly allocated to blinded intravenous infusion of L-glutamicacid solution or saline. The primary endpoint was a composite of postoperative mortality (≤30 days), perioperative myocardial infarction and left ventric ular heart failure in association with weaning from cardiopulmonary bypass. Secondary endpoints included neurological safety issues, degree of myocardial injury,postoperative hemodynamic state, use of circulatory support and cardiac mortality.The event rate was lower than anticipated and the primary endpoint did not differ significantly between the groups. Regarding secondary endpoints there were significant differences compatible with a beneficial effect of glutamate on post-ischemic myocardial recovery. The putative effect of glutamate infusion was seen in more ischemic patients (CCS class IV) and in patients with evident or anticipated LV-failure on weaning from CPB. No evidence for increased incidence of clinical or subclinical neurological injury was found. In conclusion, intravenous glutamate infusion is safe in the dosages employed and could provide a novel and important way of promoting myocardial recovery after ischemic injury.

Surgical myocardial revascularization remains the standard of care for patients with multi-vessel coronary artery disease. A growing body of evidence indicates that systemic inflammation and myocardial oxidative stress are associated with the development of postoperative atrial fibrillation (POAF) and low cardiac output syndrome in patients undergoing cardiac surgery. Statins have been shown to exert rapid anti-inflammatory and antioxidant effects by inhibiting myocardial NOX2 oxidases and by increasing the bioavailability of nitric oxide (NO). However, whether these so-called pleiotropic effects of statins result in improved patient outcomes remains to be established. To provide further insights into the mechanisms of action and impact on clinical outcomes of peri-operative statin treatment in patients undergoing cardiac surgery, I studied the molecular mechanisms underlying the myocardial nitroso-redox balance in samples of the right atrial appendages (RAA) obtained before (PRE) and after cardiopulmonary bypass (CPB) and reperfusion (POST) and setup two double-blind randomised placebo-controlled trials: 1) STARR (Statin Treatment on Atrial Refractoriness and Reperfusion injury), which tested the effect of Atorvastatin (80 mg once daily for up to 6 days before surgery and 5 days after) on the atrial effective refractory period (AERP, over 4 post-operative days) and superoxide production in paired PRE- and POST- RAA samples from 60 patients 2) STICS (Statin Treatment In Cardiac Surgery), which assessed the effects of peri-operative treatment with Rosuvastatin (20mg od) on POAF (assessed by continuous holter ECG monitoring for 5 days postoperatively) and myocardial injury (assessed by serial troponin I measurements) in 1922 patients undergoing elective cardiac surgery. I observed that atrial superoxide production increased significantly after reperfusion due to increased mitochondrial and NOX2 oxidase activity and to uncoupling of NOS activity. NOS activity in RAA samples decreased significantly after reperfusion (by 60%), but this reduction was not prevented by BH4 supplementation (10 μM) or NOX2 inhibition. Instead, I identified increased endothelial NOS S-glutathionylation as the main mechanism responsible for NOS uncoupling after reperfusion. In STARR, atorvastatin prevented increase in RAA superoxide production, maintained the functionally coupled status of NOS and NO bioavailability after reperfusion but had no measurable effect on postoperative AERP. In STICS, treatment with rosuvastatin significantly reduced LDL-C concentration by 48 hours after surgery but had no effect on the incidence of POAF (203 (21%) of the Rosuvastatinallocated patients vs. 197 (20%) of the placebo-allocated patients) or on perioperative myocardial damage (P = 0.80). Pre-defined subgroup analyses (age, sex, prior statin use, baseline troponin concentration, duration of randomized treatment before surgery, type of cardiac surgery, and postoperative use of anti-inflammatory drugs) did not identify any category of patient who benefited from perioperative rosuvastatin treatment. Nor were there beneficial effects on any of the other in-hospital clinical outcomes that were assessed. In conclusion, cardiac surgery on CPB is associated with myocardial nitroso redox imbalance that is reversed by perioperative intensive therapy with statins. However, these effects have no beneficial effects on common in-hospital complications after elective cardiac surgery. Although the benefits of long-term statin therapy in patients requiring myocardial revascularization are well established, the work presented in this thesis does not support routine use of perioperative intensive therapy with statins for the prevention of postoperative complications in patients undergoing elective cardiac surgery.

Made available in DSpace on 2016-06-02T19:48:22Z (GMT). No. of bitstreams: 1 5003.pdf: 2058659 bytes, checksum: 631c9ff761bcd738bfb1237e51455da8 (MD5) Previous issue date: 2013-02-28 / Some activities need to be stimulated in post-cardiac surgery, such as, mobilization, coughing, deep breathing exercises to avoid complications; however, these activities may be hinder by pain. An assessment of the pain at rest and during activities is needed in order to better deal with this occurrences. The main aim of this study was to assess the perception of pain after cardiac surgery via sternotomy during rest and in five selected activities (coughing, turning aside, deep breathing, sitting or standing up from a chair, and walking); the specific objectives were to identify the location and intensity of pain during rest and activities in postoperative cardiac surgery patients in the 1st, 2nd, 3rd and 6th days; to link the pain intensity with the activities and at rest, considering the postoperative days; to link the pain intensity with variables clinical-surgical; to characterize the pain through pain descriptors. A descriptive study of prospective cohort was carried out. A tool to collect socio-demographic and surgicalclinical data, a Multidimensional Scale for Pain Assessment (EMADOR) that consists of a numeric scale for pain intensity assessment, a body diagram to assess the pain location and an escalation of acute pain descriptors, were utilised. A total of 48 patients who undergone a cardiac surgery via sternotomy participated. All patients complained of pain during one of the activities in at least one of the postoperative days. The pain intensity at rest in the postoperative cardiac surgery was assessed to lessen with day in the following postoperative days. However, during the activities the pain level decreased from the 3rd, excepting for the coughing activity which decreased only in the 6th. The decreasing order of strength, when assessed the pain levels of all days, was: coughing, turning aside, deeply breathing and resting. The sternal region was the most frequently cited location of pain, followed by the epigastric region. The variables gender, age, type and duration of surgery showed weak correlation with the pain level. The keywords that best characterised the pain after cardiac surgery via sternotomy were: strong, intense, terrifying, deep and very severe. The high levels of pain may be contributing to a longer recovery period. The patients considered painful the multidimensionality of the phenomenon when using descriptors to characterize the perceived pain. The study allowed a better understanding of the aspects related to pain in the postoperative cardiac surgery. / Algumas atividades precisam ser estimuladas no pós-operatório de cirurgia cardíaca, como a mobilização, a tosse, os exercícios de respiração profunda para se evitar complicações, no entanto, podem ser prejudicadas pela presença da dor. A avaliação da dor em repouso e durante as atividades é necessária para que haja um melhor manejo deste fenômeno. Este estudo teve como objetivo geral avaliar a percepção da dor em repouso e durante cinco atividades esperadas (ao tossir, ao virar-se de lado, à respiração profunda, ao sentar ou levantar da cadeira e ao deambular) no pós-operatório de cirurgia cardíaca por esternotomia mediana; e específicos identificar a intensidade e a localização de dor durante o repouso e as atividades em sujeitos submetidos à cirurgia cardíaca, no 1º, 2º, 3º e 6º dias pós-operatório; realizar associação entre intensidade da dor e as atividades e em repouso, considerando os dias de pós-operatório; realizar associação entre intensidade de dor e variáveis clínicocirúrgicas; caracterizar a dor por meio de descritores de dor. Foi realizado um estudo descritivo, de coorte prospectivo. Foi utilizado um instrumento para coleta de dados sociodemográficos e clínico-cirúrgicos, a Escala Multidimensional para Avaliação da Dor percebida (EMADOR) que consta de uma escala numérica de avaliação da intensidade da dor, um diagrama corporal para avaliar a localização da dor e de um escalonamento de descritores de dor aguda. Participaram 48 sujeitos submetidos à cirurgia cardíaca eletiva por esternotomia. Todos os participantes tiveram queixas de dor ao menos em um dos dias de pósoperatório, em uma das atividades. A dor durante o repouso no pós-operatório de cirurgia cardíaca apresentou-se de intensidade decrescente com o passar dos dias de pós-operatório. No entanto, durante as atividades, a intensidade de dor diminuiu a partir do 3º pós-operatório, com exceção da atividade tossir em que a intensidade de dor diminuiu apenas no 6º pósoperatório. A ordem decrescente das atividades, quando avaliados os índices de intensidade de dor de todos os dias, foram tossir, virar-se de lado, respirar profundamente e em repouso. A incisão cirúrgica na região do esterno foi o local de dor mais referido pelos sujeitos, seguido da região epigástrica. As variáveis sexo, idade, tipo e tempo de cirurgia mostraram fraca associação com a intensidade de dor. Os descritores que mais caracterizaram a dor póscirurgia cardíaca por esternotomia foram forte, intensa, terrível, profunda e violenta. Os níveis elevados de dor podem estar contribuindo para um prolongamento do processo de recuperação. Os sujeitos consideram a multidimensionalidade do fenômeno doloroso ao utilizar de descritores para caracterizar a dor percebida. A investigação permitiu a melhor compreensão de aspectos relacionados à dor no pós-operatório de cirurgia cardíaca.

In the past years, the cardiac surgery performance was very demanding. The limited range of medical performances, imperfect procedures and techniques resulted in frequent postoperative complications and high postoperative mortality. Over time, surgical techniques, heart replacements, extracorporeal circulation and postoperative care have improved. This makes it possible today to operate on much older patients, where surgeries previously were nor feasible. The diploma thesis on the topic Cardiac surgical patient in the RES room and the approach of a nurse to nursing care is dedicated to the patient after heart surgery. It deals with meeting the patient's needs in the RES room and what the patient perceives while staying in the resuscitation unit and what he /she needs from a nurse. In the empirical part of this thesis two objectives were stated. To determine what a cardiac surgical patient perceives and what he /she needs in the RES room, and to find out whether it is possible to improve the quality of patient-oriented care. Based on these objectives, hypotheses and research questions were established. The objectives were successfully achieved, the hypothesis was confirmed and the questions answered. The research was conducted using qualitative quantitative research methods in the RES units of the cardiac surgery department, where the patients with heart disease are operated on. For the quantitative research the questionnaire interview method was selected. The qualitative research method was used to carry out semi-conducted interviews with the patients.

Un bio-marqueur est un paramètre biologique absent ou exprimé à un taux basal en situation physiologique, et présent ou surexprimé en cas d'altération de la fonction tissulaire correspondante. Le dosage de certain bio-marqueurs permet de suivre voire d'anticiper la survenue d'une complication en post-opératoire, et permet la prise en charge rapide et adaptée de cette complication. Les patients opérés cardiaques sont exposés à plusieurs types de complications. Les plus importantes sont l'ischémie myocardique résiduelle voire l'infarctus péri-opératoire, les complications respiratoires, l'insuffisance rénale et les infections de la cicatrice sternale. Chacune de ces complications augmente la morbi-mortalité post-opératoire. Le dosage de la TROPONINE I CARDIAQUE a montré son intérêt dans la détection des ischémies myocardiques résiduelles et le diagnostic d'infarctus péri-opératoire. Nous avons testé l'intérêt du ratio Troponine I cardiaque à 12h / Troponine I cardiaque à 6h dans la détection des ischémies myocardiques résiduelles post-opératoires. Nous avons démontré qu'un rapport de troponine H 12/H6> 1.3 permet de détecter les lésions des greffons au décours de pontages coronariens. Leur détection précoce permet de prévenir l'évolution péjorative des greffons. La NEUTROPHIL GELATINASE-ASSOCIATED LIPOCALIN (NGAL), est un marqueur de l'insuffisance rénale jamais encore testé chez les patients insuffisants rénaux chroniques en pré-opératoire de chirurgie cardiaque. Nous avorn démontré que la NGAL plasmatique est un marqueur robuste de l'apparition d'une insuffisance rénale aigüe en post­opératoire de chirurgie cardiaque, chez des patients déjà insuffisants rénaux en pré-opératoire. Un taux de NGAL à la 6ème heure supérieur à l 55ng/ml est un facteur de risque indépendant de survenue d'une insuffisance rénale aigüe post­opératoire. L'ENDOCAN est un marqueur de l'atteinte pulmonaire, qui n'a jamais été testé dans le cadre de la chirurgie cardiaque. Nous proposons de: 1) Déterminer la cinétique de L'Endocan dans le contexte inflammatoire de la CEC, 2) Evaluer le lien entre la diminution du taux d'Endocan circulant et le risque d'évolution vers une défaillance respiratoire d'origine septique ou inflammatoire, 3) Comparer la cinétique de l'Endocan à celle d'autres marqueurs de l'inflammation et de l'infection: Protéine C Réactive (CRP) et procalcitonine (PCT), et 4) Evaluer la valeur pronostique du taux d'Endocan dans la survenue des décès postopératoires d'origine respiratoire. Nous avons réalisé une étude pilote qui a mis en évidence que 6 heures après l'intervention, les patients ayant présenté une infection pulmonaire post-opératoire avaient des niveaux significativement plus élevés d'Endocan que les patients sans infection pulmonaire. Cette étude pilote a montré un intérêt potentiel pour concevoir une étude spécifique, qui a été soumise pour publication. Nous avons réalisé secondairement une étude prospective incluant 155 patients. Les résultats confirment ceux de l'étude pilote à savoir que le taux d'Endocan en préopératoire et à 6 heures est prédictif de l'atteinte pulmonaire post-opératoire. / A biomarker is a biological parameter absent or expressed at a basal Ievel in physiological situation, and present or overexpressed in the event ofalteration of the corresponding tissue function. The dosage ofsome biomarkers makes it possible to follow or even anticipate the occurrence of a postoperative complication, and allows a rapid and adapted management ofthis complication. Patients with heart surgery are exposed to several types of complications. The most important are residual myocardial ischemia and perioperative infarction, respiratory complications, renal insufficiency and sternal wound infections. Each c these complications increases post-operative morbidity and mortality. The determination of the cardiac TROPONINE I has shown its interest in the detection ofresidual myocardial ischemia and the diagnosis ofperioperative infarction. We tested the cardiac Troponin I ratio at 12 h / cardiac Troponin I at 6 h in the detection ofpost-operative residual myocardial ischemia. We have demonstrated that a ratio oftroponin Hl2 / H6> 1.3 makes it possible to detect the lesions of the grafts after coronary bypass surgery. Their early detection makes it possible to prevent the pejorative evolution of the grafts. NEUTROPHIL GELATINASE-ASSOCIATED LIPOCALIN (NGAL), is a marker ofrenal failure never tested in patients with chronic renal failure in preoperative cardiac surgery. We have demonstrated that plasma NGAL is a robust marker for the development of acute renal failure in postoperative cardiac surgery in patients with pre-operative renal failure. An NGAL level at the 6th hour above 155ng / ml is an independent risk factor for the occurrence of post­operative acute renal failure. ENDOCAN is a marker ofpulmonary involvement, which has never been tested in cardiac surgery. We propose to: 1) Determine the kinetics ofEndocan in the inflammatory context of the CEC, 2) Assess the Iink between the decrease in circulating endocan and the risk ofprogress towards respiratory failure ofseptic origin or Inflammatory, 3) Compare endocan kinetics with other markers of inflammation and infection: Protein C Reactive (CRP) and procalcitonin (PCT), and 4) Assess the prognostic value of the rate of inflammation, Endocan in the occurrence ofpostoperative respiratory deaths. We conducted a pilot study that found that 6 hours after the procedure, patients with postoperative pulmonary infection had significantly higher levels ofEndocan than patients without pulmonary infection. This pilot study showed a potential interest in designing a specific study, which was submitted for publication. We performed a prospective study, which included 155 patients. The results confirm the results of the pilot study, namely that the preoperative and 6-hour Endocan is predictive ofpostoperative pulmonary involvement

Introdução: Desmame da ventilação mecânica representa um importante desafio no ambiente de terapia intensiva. Os preditores ao desmame têm se mostrado pouco sensíveis e a falência na extubação pode determinar prolongada ventilação mecânica, aumento do tempo de permanência na UTI, na internação hospitalar, com consequentemente aumento nos custos hospitalares e aumento da morbidade e mortalidade. O objetivo do estudo foi verificar se novos indicadores: BNP (peptídeo natriurético Tipo-B), CPO (cardiac power out put) e VeRT (tempo de recuperação do volume minuto), são mais sensíveis em comparação aos preditores já utilizado para o desmame ventilatório. Método: Foram prospectivamente avaliados 101 pacientes no pós-operatório de Revascularização do Miocárdio. As variáveis respiratórias analisadas foram: freqüência respiratória, volume corrente, volume minuto, índice de respiração rápida e superficial, complacência estática, índice de oxigenação (PaO2/FiO2). As variáveis hemodinâmicas e metabólicas foram: FC, PAM, PVC, PCP, DC, IC, Lactato, SvO2, ERO2, D(a-v)O2, DO2 e VO2. Foram também testados os novos indicadores CPO, BNP e VeRT. Consideramos aptos para extubação os pacientes que apresentaram nível de consciência adequado e critérios positivos para o desmame corriqueiramente utilizados em U.T.I. Resultados: No total de 713 pacientes observados, 105 pacientes foram incluídos no estudo, desses pacientes quatro não foram extubados por desconforto respiratório, dos 101 pacientes acompanhados, 88 (88%) evoluíram com sucesso ao desmame e 12 (12%) evoluíram com insucesso. Não houve diferença estatisticamente significante entre os grupos, no que diz respeito aos dados antropométricos. As variáveis: freqüência respiratória, volume corrente, volume minuto, índice de respiração rápida e superficial, complacência estática, PaO2/FiO2, FC, PAM, PVC, PCP, DC, IC, DO2, VO2, Lactato e os novos indicadores CPO e VeRT, não foram sensíveis como preditores de sucesso ao desmame. Na análise multivariada o grupo sucesso apresentou até o momento pré-extubação, um menor tempo de permanência de U.T.I. (3,9 x 10,33, p=0, 024), menor tempo de internação hospitalar (11,29 x 16,08, p=0,047), menor necessidade de inotrópico dobutamina (12,90 x 16,67, p=0,049), uma maior SVO2 (69,18 x 61,67, p 0,002), menor ERO2 (0,45 x 0,62, p=0,03), menor D(a-v)O2 (4,34 x 5,10, p=0,039), e um menor nível de BNP (98,94 x 303,33, p=0,020), quando comparado com grupo insucesso, nesta ultima variável BNP à análise da curva ROC, mostrou uma sensibilidade de 83% e especificidade 87%. Conclusão: A prevalência de insucesso ao desmame ventilatório no pósoperatório de cirurgia cardíaca foi de 12%, os pacientes que evoluíram com insucesso apresentaram maior tempo de U.T.I., maior tempo de internação hospitalar e maior necessidade de inotrópico. No momento pré-extubação altos níveis de BNP, D(a-v)O2, ERO2 e baixo valores de SvO2, são preditores de sucesso ao desmame. Com isso a adequada otimização hemodinâmica prévia a extubação deve ser alcançada nessa população para se conseguir um seguro e precoce desmame da ventilação mecânica / Introduction: Weaning from mechanical ventilation represents a major challenge in the intensive care setting. The weaning predictors have shown little sensitivity and extubation failure may determine prolonged mechanical ventilation, prolonged ICU stay and prolonged hospitalization, with a consequent increase in hospital costs and increased morbidity and mortality. The objective of this study was to determine whether new indicators (BNP, CPO and VeRT), are more sensitive compared with predictors already used for weaning. Method: We prospectively evaluated 101 patients in post-operation stage of Myocardial Revascularization. Respiratory variables were analyzed: respiratory rate, tidal volume, minute volume, index of rapid shallow breathing, static compliance, oxygenation index (PaO2/FiO2). The hemodynamic and metabolic variables were: HR, MAP, CVP, PCWP, DC, IC, Lactate, SvO2, ERO2, D(a-v)O2, DO2 and VO2. We also tested the new indicators CPO, BNP and VeRT. We considered suitable for extubation patients that had appropriate levels of awareness and positive criteria for weaning routinely used in ICU. Results: From a total of 713 patients observed, 105 patients were included in the study; from these patients 4 were not extubated because of respiratory distress. From the 101 patients enrolled, 89 (88%) had successful weaning and 12 (12%) developed failure. There was no statistically significant difference between groups with respect to demographics. The variables: respiratory rate, tidal volume, minute volume, index of rapid shallow breathing, static compliance, PaO2/FiO2, HR, MAP, CVP, PCWP, DC, CI, DO2, VO2, lactate and new indicators CPO and VeRT were not as sensitive predictors of successful weaning. In multivariate analysis the group that had success until the pre-extubation stage a shorter length of stay in ICU (3.9 x 10.33, p = 0 024), shorter hospital stay (11.29 x 16.08, p = 0.047), less need for inotropic dobutamine (12.90 x 16.67, p = 0.049) greater SVO2 (69.18 x 61.67, p <0.002), lower ERO2 (0.45 x 0.62, p = 0.03), lower D(a-v)O2 (4.34 x 5.10, p = 0.039), and a lower level of BNP (98.94 x 303.33, p = 0.020) when compared to the failure group; this last variable BNP, in the ROC curve analysis, showed a sensitivity of 83 % and specificity of 87%. Conclusion: The prevalence of failure in ventilatory weaning in post-operatory of cardiac surgery was 12%; patients who developed failure had longer ICU and hospital stay and greater need for inotropic medicine. Upon pre-extubation high levels of BNP, D(a-v)O2, ERO2 and low values of SvO2 are strong predictors of successful weaning. With that, adequate hemodynamic optimization prior to extubation in this population must be reached to achieve a safe and early weaning from mechanical ventilation

Orientador: Desanka Dragosavac / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciencias Medicas / Made available in DSpace on 2018-08-13T01:37:02Z (GMT). No. of bitstreams: 1 Rodrigues_CristianeDelgadoAlves_M.pdf: 1445423 bytes, checksum: 1cb94c1d7b130ae811ccc39e11e545d7 (MD5) Previous issue date: 2009 / Resumo: A insuficiência respiratória após a cirurgia cardíaca com utilização da circulação extracorpórea (CEC) é resultante de inúmeros fatores relacionados à Síndrome de Resposta Inflamatória Sistêmica (SIRS). Grande número desses pacientes desenvolve Lesão Pulmonar Aguda (LPA) e alguns até Síndrome da Angústia Respiratória no Adulto (SARA). Há inúmeros fatores que podem influenciar direta e/ou indiretamente a lesão pulmonar observada no pós-operatório de pacientes submetidos à cirurgia cardíaca com CEC. A própria ventilação mecânica (VM) pode causar lesão pulmonar induzida pela ventilação (LPIV). Discutem-se técnicas e métodos ventilatórios que visam prevenir e corrigir a hipoxemia freqüentemente observada nessa condição. No entanto, ainda não há na literatura consenso sobre qual a melhor modalidade ventilatória a ser empregada. As propostas gerais de suporte ventilatório com baixos volumes, pressão limitada, fluxo decrescente e PEEP (pressão positiva no final de expiração), além de evitar a transfusão desnecessária, devem ser usadas para minimizar a lesão pulmonar em cirurgia cardíaca. O objetivo principal deste trabalho foi comparar o efeito das modalidades ventilatórias pressão controlada e volume controlado na função respiratória e reações inflamatórias de pacientes submetidos à cirurgia cardíaca eletiva com circulação extracorpórea. Participaram deste estudo 22 pacientes submetidos à cirurgia cardíaca com circulação extracorpórea. Onze foram submetidos à ventilação com pressão controlada, fluxo decrescente e PEEP de 5 cmH2O (Ventilador Esprit - PCV/E), 5 pacientes à ventilação com volume controlado, fluxo decrescente e PEEP de 5 cmH2O (Ventilador Esprit - VCV/E) e 6 pacientes à ventilação com volume controlado, fluxo quadrado, sem PEEP (Ventilador Takaoka - VCV/T), usado de rotina no Centro Cirúrgico.Na UTI os pacientes foram ventilados com ventilador Espirit na modalidade de SIMV (pressão ou volume controlado), associado ao suporte pressórico, que foi usado também para desmame nos três grupos. A monitorização respiratória foi feita com aparelho NICO2/Dixtal. As reações inflamatórias foram mensuradas através do lactato e leucócitos. Os parâmetros ventilatórios monitorizados foram: PaO2/FiO2, PaCO2, volume expirado, pressão de pico inspiratória, complacência dinâmica, resistência das vias aéreas, ventilação alveolar, espaço morto e tempo de ventilação mecânica. Todos os pacientes apresentaram lesão pulmonar e o grupo VCV/T apresentou SARA no final da cirurgia. O índice de oxigenação apresentou queda no decorrer do tempo nos três grupos (p=0.002), com pior resultado na admissão do paciente na UTI. A pressão parcial de gás carbônico (PaCO2) não apresentou alterações estatisticamente significantes. O volume corrente expirado (VT EXP) apresentou aumento apenas no grupo PCV/E antes e após a CEC (p=0.0081). A pressão inspiratória das vias aéreas (PIT) aumentou no decorrer do tempo nos três grupos (p=0.0411), sem diferença entre os grupos. A complacência dinâmica (C DIN) apresentou queda no decorrer do tempo nos três grupos (p=0.0063), sem diferença entre os grupos. A resistência de vias aéreas (R VAs) aumentou no decorrer do tempo nos três grupos, apresentando diferença estatisticamente significante apenas no grupo VCV/T (p=0.0012), comparado com demais grupos. O espaço morto fisiológico (VD/VT) e a ventilação alveolar (V ALV) não apresentaram alterações nem entre grupos nem no decorrer do tempo. O lactado aumentou no decorrer do tempo após a CEC nos três grupos (p<0.0001), diminuiu após 48 horas de UTI, mas não retornou aos valores iniciais. Os leucócitos apresentaram aumento dos valores no decorrer do tempo nos três grupos (p<0.0001). Não houve diferença de lactato e leucócitos entre os grupos. Concluise que todos pacientes apresentaram lesão pulmonar aguda e que não houve diferença significante nos parâmetros estudados ente os grupos, exceto piora de resistência e maior lesão pulmonar no final da cirurgia no grupo VCV/T. Os dois marcadores inflamatórios, lactato e leucócitos, aumentaram devido à resposta inflamatória, sem diferença entre os grupos estudados. / Abstract: Postoperative lung injury after cardiac surgery with cardiopulmonary bypass (CPB) is usually related to the systemic inflammatory response syndrome (SIRS). Many patients undergoing this procedure develop acute lung injury (ALI), and some of them acute respiratory distress syndrome (ARDS). Many factors can be directly or indirectly related to the postoperative lung dysfunction frequently seen after cardiac surgery with CPB, including ventilator-associated lung injury (VALI). Thus, many different approaches to mechanical ventilation (MV) have been investigated with the aim of prevent and/or treat postoperative lung injury. Low-tidal-volume mechanical ventilation, plateau pressure limitation, decelerating inspiratory flow, positive end-expiratory pressure (PEEP) and a restrictive red blood cell transfusion strategy are recommended to reduce the incidence and the severity of ALI in patients undergoing cardiac surgery with CPB. The main objective of the present study was to compare the effects of pressure controlled ventilation (PCV) versus volume controlled ventilation (VCV) on postoperative pulmonary function and in the incidence of SIRS in patients undergoing scheduled cardiac surgery with CPB. The study population was composed by 22 adult patients undergoing cardiac surgery with CPB that was mechanically ventilated as following: pressure-controlled ventilation with decelerating inspiratory flow and 5 cmH2O PEEP (Ventilator Esprit - PCV/E; n = 11); volume-controlled ventilation with decelerating inspiratory flow and 5 cmH2O (Ventilator Esprit - VCV/E; n = 5) and volume-controlled ventilation with square-wave inspiratory flow and without PEEP (Ventilator Takaoka - VCV/T; n = 6). This last ventilator is routinely used only in the operating theater. In the intensive care unit (ICU) the patients were ventilated with the ventilator Espirit, by applying SIMV (pressure or volume-controlled) and pressure support ventilation (PSV), that was also used during weaning in all groups. Respiratory monitoring was done with a NICO2 apparatus (Dixtal). Systemic inflammatory response was evaluated by means of serially white blood cells (WBC) counts and serum lactate levels. The following respiratory function variables were serially measured: PaO2/FiO2, PaCO2, expired volume, peak inspiratory pressure, dynamic compliance, airway flow resistance, alveolar ventilation, physiologic dead space ventilation and time on mechanical ventilation. All patients have shown postoperative pulmonary dysfunction and in the group VCV/T a degree of lung injury compatible with ARDS definition was recorded at the end of surgical procedure. PaO2/FiO2 has shown a significant decrease during time course in all three groups (p=0.002), with a nadir at ICU admission. PaCO2 didn't show significant alterations. Expired volume has shown increase only in PCV/E group, by comparing pre- and post-CPB moments (p=0.0081). Peak airway inspiratory pressure has increased during time course in all three groups (p=0.0411), without significant differences between them. Dynamic compliance (C DIN) has shown a decrease during time course in all three groups (p=0.0063), without significant differences between them. Airway flow resistance has increased during time course in all three groups, with statistically significant difference by comparing VCV/T group with the other two (p=0.0012). Physiologic dead space ventilation (VD/VT) and alveolar ventilation (V ALV) have not shown significant alterations during time course or between groups. Serum lactate levels have increased during time course just after CPB in all three groups (p<0.0001), decreasing 48 hours after the surgical procedure, but not returning to preoperative levels. WBC counts have shown a significant time course increase in all three groups (p<0.0001). However, no significant differences in serum lactate levels serum and WBC counts were seen between groups. It was concluded that all patients undergoing cardiac surgery with CPB have shown some degree of acute pulmonary dysfunction and this complication was not apparently directly related to the mechanical ventilation modality, except by an increase in airway flow resistance and a slight high degree of acute lung injury in the VCV/T group at the end of surgical procedure. Additionally, both systemic inflammatory markers, serum lactate levels and white blood cells counts, have increased during time course in all groups, without significant differences between them. / Mestrado / Pesquisa Experimental / Mestre em Cirurgia