Impulso, esfuerzo y trabajo respiratorio: revisión de definiciones y herramientas no invasivas de ventiladores de cuidados intensivos durante tiempos de pandemia / Respiratory drive, inspiratory effort, and work of breathing: review of definitions and non-invasive monitoring tools for intensive care ventilators during pandemic times

Los avances tecnológicos de la ventilación mecánica han sido parte esencial del aumento de la sobrevida en las unidades de cuidados intensivos. Desde la conexión a la ventilación mecánica, comúnmente se utiliza ventilación controlada sin la consecuente participación de los músculos respiratorios del paciente, con el fin de favorecer la protección pulmonar. El retiro de la ventilación mecánica implica un periodo de transición hacia la respiración espontánea, utilizando principalmente ventilación mecánica asistida. En esta transición, el desafío de los clínicos es evitar la sub y sobre asistencia ventilatoria, minimizando el esfuerzo respiratorio excesivo, daño diafragmático y pulmonar inducidos por la ventilación mecánica. La monitorización con balón esofágico permite mediciones objetivas de la actividad muscular respiratoria en tiempo real, pero aún hay limitaciones para su aplicación rutinaria en pacientes ventilados mecánicamente en la unidad de cuidados intensivos. Al igual que el balón esofágico, la electromiografía de los músculos respiratorios y la ecografía diafragmática son herramientas que permiten monitorizar la actividad muscular de la respiración, siendo mínimamente invasivas y con requerimiento de entrenamiento específico. Particularmente, durante la actual pandemia de enfermedad por coronavirus se ha extendido el uso de herramientas no invasivas disponibles en los ventiladores mecánicos para monitorizar el impulso (drive), esfuerzo y trabajo respiratorio, para promover una ventilación mecánica ajustada a las necesidades del paciente. Consecuentemente, el objetivo de esta revisión es identificar las definiciones conceptuales de impulso, esfuerzo y trabajo respiratorio utilizadas en el contexto de la unidad de cuidados intensivos, e identificar las maniobras de medición no invasivas disponibles en los ventiladores de cuidados intensivos para monitorizar impulso, esfuerzo y trabajo respiratorio. La literatura destaca que, aunque los conceptos de impulso, esfuerzo y trabajo respiratorio se perciben intuitivos, no existe una definición clara. Asimismo, destacados autores los definen como conceptos diferentes.

Technological advances in mechanical ventilation have been essential to increasing the survival rate in intensive care units. Usually, patients needing mechanical ventilation use controlled ventilation to override the patient's respiratory muscles and favor lung protection. Weaning from mechanical ventilation implies a transition towards spontaneous breathing, mainly using assisted mechanical ventilation. In this transition, the challenge for clinicians is to avoid under and over assistance and minimize excessive respiratory effort and iatrogenic diaphragmatic and lung damage. Esophageal balloon monitoring allows objective measurements of respiratory muscle activity in real time, but there are still limitations to its routine application in intensive care unit patients using mechanical ventilation. Like the esophageal balloon, respiratory muscle electromyography and diaphragmatic ultrasound are minimally invasive tools requiring specific training that monitor respiratory muscle activity. Particularly during the coronavirus disease pandemic, non invasive tools available on mechanical ventilators to monitor respiratory drive, inspiratory effort, and work of breathing have been extended to individualize mechanical ventilation based on patient's needs. This review aims to identify the conceptual definitions of respiratory drive, inspiratory effort, and work of breathing and to identify non invasive maneuvers available on intensive care ventilators to measure these parameters. The literature highlights that although respiratory drive, inspiratory effort, and work of breathing are intuitive concepts, even distinguished authors disagree on their definitions.

Predictores de fracaso con cánula nasal de alto flujo de oxígeno en pacientes COVID-19 / Predictors of failure with high-flow nasal cannula oxygen in COVID-19 patients

Introducción: El COVID-19 ha generado retos por la alta demanda de servicios, haciendo necesario buscar alternativas de soporte ventilatorio que permitan responder a las necesidades de la población. Es importante disponer de herramientas que permitan detectar precozmente el fracaso de estrategias ventilatorias no invasivas e identificar tempranamente la necesidad de intubación. Objetivo: identificar las variables asociadas a fracaso en el tratamiento con cánula de alto flujo (CNAF) en pacientes con COVID-19. Materiales y Métodos: estudio observacional analítico, corte transversal con 68 pacientes de la unidad de cuidados intensivos con COVID-19, que recibieron tratamiento con CNAF. Las variables de estudio se evaluaron en tres momentos, a las 24, 48 y 72 horas, llevando a cabo un análisis bivariado y multivariado entre los que fracasaron y los que tuvieron éxito. Resultados: en el análisis bivariado las variables que presentaron una relación estadísticamente significativa a las 24h fueron el no presentar un aumento del trabajo respiratorio (Wresp) (p=0.000) y saturación de oxígeno (SatO2) normal (p=0.006). A las 48h: no aumento en Wresp (p=0.014), SatO2 normal (p=0.005), presión arterial de oxígeno/fracción inspirada de oxígeno (PAFI) leve o moderado (p=0.039). A las 72h fracasaron: PAFI severa (p=0.000), aumento de Wresp (p=0.001) y el índice de ROX menor a 4.88 (p=0.023). De acuerdo con el análisis multivariado las variables predictoras de fracaso a las 24h fueron: FIO2, SatO2, Wresp y a las 48h FIO2 y SatO2. Conclusiones: el aumento de FIO2>70 %, presentar incremento del Wresp y SpO2 menor de 88 % son variables asociadas a fracaso de la CNAF y facilitan tomar decisiones clínicas sobre avanzar o no hacia un soporte ventilatorio invasivo.

Introduction: COVID-19 has generated challenges due to the high demand for health care services, making it necessary to seek ventilatory support alternatives that allow us to fulfill the needs of the population. It is important to have tools that allow to detect the failure of non-invasive ventilatory strategies early and to identify the need for intubation on time. Objective: Identify the variables associated with failure of high-flow nasal cannula treatment (HFNC) on COVID-19 patients. Materials and Methods: Analytical observational, cross-sectional study of 68 patients in the intensive care unit with COVID-19, who received treatment with HFNC. The variables of the study were evaluated at three time points, at 24, 48 and 72 hours. A bivariate and multivariate analysis was performed between those who failed and those who were successful. Results: In the bivariate analysis, the variables that presented a statistically significant relationship at 24h were: No increase in work of breathing (WOB) (p=0.000), normal oxygen saturation (SatO2) (p=0.006). At 48h: No increase in WOB (p=0.014), normal SatO2 (p=0.005), mild to moderate partial pressure arterial oxygen/fraction inspired oxygen ratio (P/F ratio) (p=0.039). At 72h failed: severe P/F ratio (p=0.000), Increased WOB (p=0.001) and ROX index less than 4.88 (p=0.023). According to multivariate analysis the predictive variables for the therapeutic failure at 24h were: FIO2, SatO2, WOB; at 48h: FIO2 and SatO2. Conclusions: Increased FIO2>70%, increased WOB and SpO2 less than 88% are variables associated with failure of HFNC, and facilitate clinical decisions on whether or not to progress with invasive ventilatory support.

Comportamiento clínico y gasométrico en falla respiratoria aguda tratada con cánula nasal de alto flujo / Clinical and gasometric behavior in acute respiratory failure treated with a high-flow nasal cannula

Introducción: La cánula nasal de alto flujo en adultos ofrece un tratamiento alternativo a la oxigenoterapia convencional. Objetivo: Establecer el comportamiento clínico y gasométrico de pacientes con falla respiratoria aguda que habitan a 2.600 msnm, tratados con cánula nasal de alto flujo en cuidado intensivo adulto. Materiales y métodos: Estudio piloto cuasi experimental pretest-postest intrasujeto, tamaño de muestra 14 pacientes calculado a través de Epidat. Tipo de muestreo no probabilístico por conveniencia, durante catorce meses. Resultados: El 78% de los pacientes fueron mujeres, la edad promedio fue 68 años, y el diagnóstico principal fue enfermedad pulmonar obstructiva crónica (EPOC) en el 71,42% de los casos. Se administró un flujo de oxígeno promedio de 30 Lt/min para pacientes con (EPOC), para el resto de diagnósticos se programaron flujos mayores. El trabajo respiratorio disminuyó posterior al uso de cánula nasal de alto flujo, la presión arterial de oxígeno mejoró paulatinamente en pacientes con falla hipoxémica y el índice de oxigenación incrementó progresivamente en los dos tipos de falla respiratoria. Conclusiones: La cánula nasal de alto flujo es una opción terapéutica útil en el manejo de la falla respiratoria aguda a 2.600 msnm, permitiendo mejoría de la oxigenación y disminución del trabajo respiratorio.

Introduction: High-flow nasal cannula offers an alternative treatment approach to conventional oxygen therapy in adults. Objective: To establish the clinical and gasometric behavior of patients with acute respiratory failure who live at 2,600 m.a.s.l. and are treated with high-flow nasal cannula in an adult intensive care unit. Materials and methods: Quasi-experimental pilot study with a pretest-posttest within-subject design and a sample size of 14 patients calculated through Epidat. A non-probabilistic convenience sampling was conducted for fourteen months. Results: 78% of the patients were women and their average age was 68 years. Chronic Obstructive Pulmonary Disease (COPD) was diagnosed in 71.42% of the cases. An oxygen flow rate of 30 L/min was administered to patients with Chronic Obstructive Pulmonary Disease, while higher rates were used for the rest of the diagnoses. Nasal cannula treatment led to (i) a decreased respiratory function, (ii) a gradually improved arterial blood pressure in patients with hypoxemic failure, (iii) and a progressively increased oxygenation rate. Conclusions: High-flow nasal cannula is a useful therapeutic option in the management of patients with acute respiratory failure living at 2,600 m.a.s.l. because it improves oxygenation and reduces respiratory function.

Efectos fisiológicos de las terapias de soporte respiratorio no invasivo y su potencial rol postextubación / Physiological effects of non-invasive respiratory support therapies and their potential post-extubation role

Posterior a una extubación programada existe un porcentaje de pacientes que fracasa y requiere reintubación (~20%), este evento es conocido como fracaso de extubación, el cual se asocia con mayor morbimortalidad. Para prevenir el fracaso de extubación se han propuesto terapias como la ventilación no invasiva (VNI) y la cánula nasal de alto flujo (CNAF). Estas terapias son capaces de entregar soporte respiratorio postextubación y justifican su uso en los efectos fisiológicos que son capaces de inducir, en dónde el impacto sobre el esfuerzo respiratorio e intercambio de gases sería fundamental. Con esta racionalidad fisiológica se han desarrollado diversos estudios en diferentes contextos clínicos, esto con el fin de dilucidar cuál terapia es la mejor alternativa. En esta revisión narrativa pretendemos describir y analizar los diversos efectos fisiológicos que induce la VNI y la CNAF

Rebirthing-Breathwork, activation of the autonomic nervous system, and psychophysiological defenses / Rebirthing-Breathwork, ativação do sistema nervoso autónomo, e defesas psicofisiológicas / Rebirthing-Breathwork, activación del sistema nervioso autónomo, y defensas psicofisiológicas

Rebirthing-Breathwork can be described as a technique that uses the breathing rhythm to activate a somaticcognitive cycle. When allowed to unfold, this cycle spontaneously brings unresolved issues to consciousness and leads to their resolution. This is an analytic and interpretative study with the goal to present a theoretical basis for a processing model that the authors are developing to use Rebirthing-Breathwork in the treatment of traumatic stress-related disorders. In this essay we discuss Rebirthing-Breathwork in the light of a theory and an approach developed by Peter Levine and address the role psychophysiological defenses and the autonomic nervous system play in accessing suppressed and traumatic memories. Based on personal and clinical evidence we describe how Rebirthing-Breathwork activates suppressed and traumatic memories; how these activated memories activate one of two types of psychophysiological defenses; and how these defenses can be negotiated by means of mindfulness, embodiment and empowerment, so that the activated memories can be processed.(AU)

Rebirthing-Breathworkpode ser descrito como uma técnica que utiliza o ritmo respiratório para ativar um ciclo cognitivo-somático. Quando permitido o seu desenvolvimento, este ciclo traz questões não resolvidas à consciência, conduzindo-as à sua resolução. Este artigo é um estudo analítico-interpretativo com o objetivo de apresentar a base teórica para um modelo de processamento que está sendo desenvolvido pelos autores para utilização do trabalho respiratório - Rebirthing-Breathwork - no tratamento de transtornos traumáticos relacionados ao estresse. Neste ensaio discutimos o Rebirthing-Breathwork à luz de uma teoria e uma abordagem desenvolvida por Peter Levine e tratamos sobre o papel que as defesas psicofisiológicas e o sistema nervoso autônomo desempenham no acesso a memórias reprimidas e traumáticas. Com base em evidências pessoais e clínicas, descrevemos como o trabalho de Rebirthing-Breathworkativa memórias reprimidas e traumáticas e como essas memórias ativadas, por sua vez, provocam um dos dois tipos de defesas psicofisiológicas. Descrevemos, ainda, como se pode lidar com essas defesas através de mindfulness, de uma melhor conexão com o corpo e empoderamento, a fim de que essas memórias ativadas possam ser processadas.(AU)

El Rebirthing-Breathwork se puede describir como una técnica que usa el ritmo respiratorio para activar un ciclo cognitivo-somático. Cuando el ciclo se desarrolla, espontáneamente lleva a la consciencia problemas no resueltos y los conduce a su resolución. Este es un estudio analítico-interpretativo con el objetivo de presentar una base teórica para el modelo de procesamiento que los autores están desarrollando, cuya finalidad es la utilización del trabajo respiratorio - Rebirthing Breathwork - en el tratamiento de los trastornos traumáticos relacionados con el estrés. En este ensayo discutimos el Rebirthing Breathwork con base en una teoría y un enfoque desarrollado por Peter Levine, y abordamos el papel que desempeñan las defensas psicofisiológicas y el sistema nervioso autónomo en el acceso a memorias reprimidas y traumáticas. Con base en evidencias personales y clínicas, describimos cómo el trabajo de Rebirthing-Breathwork activa memorias reprimidas y traumáticas; cómo estos recuerdos activados, a su vez, activan uno de los dos tipos de defensas psicofisiológicas; y cómo podemos tratar esas defensas por medio del mindfulness, de una mejor conexión con el cuerpo y del empoderamiento, con la finalidad de procesar las memorias activadas.(AU)

Effect of Breathing Exercise Using Panflutes on the Postoperative Compliance, Pulmonary Infections and Life Satisfaction in Elderly Patients Undergoing Spinal Surgery

PURPOSE: The purpose of this study was to examine the effects of breathing exercises performed using panflutes in elderly patients undergoing spinal surgery. METHODS: The study design was a nonequivalent control group non-synchronized pre-post test. The study included 24 patients in both the experimental group and the control group. The experimental group completed a daily breathing exercise regimen using panflutes for 30minutes after meals, whereas the control group was provided standard preoperative education, including breathing exercises using incentive spirometers. After the exercise regimen, breathing exercise compliance, pulmonary infections, and life satisfaction were measured in both groups, and the data were analyzed using the SPSS/WIN program. RESULTS: The compliance rate of breathing exercises was significantly higher in the experimental group. The experimental group presented no pulmonary infections in the later period, whereas the control group presented higher pulmonary infection rates in the same period. In addition, the life satisfaction score in the experimental group significantly increased. CONCLUSION: The breathing exercise program using panflutes for elderly patients undergoing spinal surgery enhanced their breathing exercise compliance and their daily life satisfaction in addition to reducing their pulmonary infection rates.

Fisioterapia no paciente com asma: intervenção baseada em evidências / Physiotherapy in asthma patients: evidence-based intervention

As intervenções fisioterapêuticas destacam-se como tratamento não farmacológico e são coadjuvantes no tratamento da asma. O tratamento fisioterapêutico só deve ser iniciado quando o indivíduo estiver com a medicação ajustada para sua condição e em acompanhamento médico regular. Como a asma é uma doença crônica com episódios recorrentes de sibilância, tosse e dispneia, ocorre aumento do trabalho respiratório e da percepção do esforço, podendo levar a alterações da mecânica respiratória, função muscular respiratória e do descondicionamento físico. Os objetivos da fisioterapia são: reduzir o desconforto respiratório e a dispneia, melhorar a mecânica respiratória, melhorar a força muscular respiratória nos casos de fraqueza desta musculatura, melhorar o condicionamento cardiorrespiratório, promover higiene brônquica, quando necessária, e melhorar a qualidade de vida. Estudos prévios investigaram os efeitos dos exercícios respiratórios, do treinamento muscular respiratório (TMR), da reabilitação pulmonar (RP) e das técnicas de higiene brônquica em pacientes asmáticos. Não há evidências de que os exercícios respiratórios melhorem a função pulmonar, embora reduzam os sintomas e a medicação de resgate e melhorem a qualidade de vida. O TMR diminui a dispneia, aumenta a força muscular inspiratória e melhora a capacidade de exercício. O treinamento físico, que é o principal componente da RP, leva à melhora dos sintomas respiratórios, da capacidade funcional e qualidade de vida. Por fim, não há evidências científicas que suportem a realização de técnicas manuais de higiene brônquica. No entanto, o oscilador oral de alta frequência pode ser uma estratégia para eliminar secreção de adultos e crianças na vigência de infecção pulmonar.

Respiratory physiotherapy stands out as a nonpharmacological approach and is an adjuvant intervention in the treatment of asthma. Physiotherapy should only be initiated when the medication is adjusted to the patient's condition and when the patient is under regular medical follow-up. Asthma is a chronic disease with recurrent episodes of wheezing, cough, and dyspnea, resulting in increased respiratory workload and perceived exertion and potentially leading to changes in respiratory mechanics, respiratory muscle function, and physical deconditioning. The objectives of respiratory physiotherapy are: to reduce respiratory distress and dyspnea, to improve respiratory mechanics and respiratory muscle strength (in cases of muscle weakness), to improve cardiopulmonary conditioning, to promote bronchial hygiene when necessary, and to improve quality of life. Previous studies have investigated the effects of breathing exercises, respiratory muscle training (RMT), pulmonary rehabilitation (PR), and bronchial hygiene techniques in patients with asthma. There is no evidence that breathing exercises can improve lung function, even though they reduce symptoms and the use of rescue medication and improve quality of life. RMT reduces dyspnea, increases inspiratory muscle strength, and improves exercise capacity. Physical training, the main component of PR, leads to improvement of respiratory symptoms, functional capacity, and quality of life. Finally, there is no scientific evidence supporting the use of manual bronchial hygiene techniques. Nevertheless, the use of oral high-frequency oscillators could be a strategy for mucus clearance in adults and children with pulmonary infection.

Is It Essential to Consider Respiratory Dynamics? / 대한중환자의학회지

No abstract available.

Is It Essential to Consider Respiratory Dynamics? / 대한구급학회지

No abstract available.

Avaliação da musculatura inspiratória e expiratória na doença pulmonar obstrutiva crônica leve e grave comparada aos indivíduos saudáveis / Evaluation of the inspiratory and expiratory muscles in mild and severe chronic obstructive pulmonary disease stages compared to healthy individuals

A DPOC é uma doença respiratória prevenível e tratável, caracterizada por limitação persistente ao fluxo aéreo, hiperinsuflação e aprisionamento aéreo. A dispneia e a intolerância aos esforços, decorrentes destas alterações fisiopatológicas sofre influência de vários fatores. Dentre estes, o recrutamento e a sobrecarga imposta aos músculos inspiratórios e expiratórios são de fundamental importância, porém a participação destes ainda não foi completamente elucidada em diferentes gravidades da doença. Objetivos: O objetivo principal deste estudo foi avaliar a mecânica ventilatória, e o grau de recrutamento da musculatura inspiratória e expiratória na DPOC leve e grave, na condição de repouso e durante um teste máximo de exercício, comparado a um grupo de indivíduos saudáveis. Metodologia: Trata-se de um estudo transversal envolvendo 36 indivíduos, sendo 24 pacientes portadores de DPOC e 12 voluntários sadios. As avaliações foram divididas em 2 visitas. No D1, foram realizadas uma avaliação clínica, avaliação de dispneia (mMRC) e de qualidade de vida (SGRQ), além da prova de função pulmonar completa. Na 2ª visita, realizada com intervalo de 1 semana, foram avaliadas: as pressões respiratórias máximas estáticas por meio de métodos volitivos (PImax, PEmax, SNIP, Pes sniff, Pga sniff e Pdi sniff) e não volitivos (Twitch cervical bilateral e T10); avaliação da sincronia toracoabdominal por pletismografia de indutância; avaliação do recrutamento dos músculos inspiratórios e expiratórios ao repouso pela eletromiografia de superfície; e, posteriormente, um teste de exercício cardiopulmonar incremental para estudo de todas essas variáveis no esforço. Resultados: Foram avaliados 24 pacientes (12 leves e 12 graves) e 12 indivíduos saudáveis da mesma faixa etária. A maioria dos pacientes apresentava comprometimento significativo da qualidade de vida e os pacientes do grupo grave eram mais sintomáticos. A função pulmonar encontrava-se alterada na maioria dos...

Chronic obstructive pulmonary disease (COPD) is a preventable and treatable respiratory disease characterized by persistent airflow limitation, lung hyperinflation and air trapping. Dyspnea and effort intolerance resulting from these pathophysiological changes are influenced by several factors. Among these, the recruitment and burden to the aspiratory and expiratory muscles are of fundamental importance but their participation has not been fully elucidated in different severities of disease. Objectives: The main objective of this study was to evaluate the mechanics of ventilation and the grade of recruitment of inspiratory and expiratory muscles in patients with mild and severe COPD, at rest and during maximum exercise, compared to a group of healthy individuals. Methods: Cross-sectional study involving 36 subjects, 24 patients with COPD and 12 healthy volunteers. The evaluations were performed in two visits. In the first visit, participants underwent a clinical evaluation, dyspnea (modified Medical Research Council) and quality of life (Saint George Respiratory Questionnaire) assessments, and complete pulmonary function test. In the second visit, which was one week later, the following evaluations were performed: maximum static respiratory pressures through volitional (MIP, MEP, SNIP, sniff Pes, sniff Pga and sniff Pdi) and non-volitional methods (cervical twitch and T10); evaluation of thoraco-abdominal synchrony by inductance plethysmography; evaluation of recruitment of the inspiratory and expiratory muscles at rest by surface electromyography; and then an incremental cardiopulmonary exercise testing to assess all of these variables under exercise conditions. Results: We evaluated 24 patients (12 with mild and 12 with severe COPD) and 12 healthy individuals of the same age group. Most patients had significant impairment of quality of life and those with severe COPD were more symptomatic. The lung function was abnormal in the majority...

Pressure support-ventilation versus spontaneous breathing with "T-Tube" for interrupting the ventilation after cardiac operations / Pressão de suporte ventilatório versus respiração espontânea em "Tubo-T" para a interrupção da ventilação após as operações cardíacas

OBJECTIVE: To compare pressure-support ventilation with spontaneous breathing through a T-tube for interrupting invasive mechanical ventilation in patients undergoing cardiac surgery with cardiopulmonary bypass. METHODS: Adults of both genders were randomly allocated to 30 minutes of either pressure-support ventilation or spontaneous ventilation with "T-tube" before extubation. Manovacuometry, ventilometry and clinical evaluation were performed before the operation, immediately before and after extubation, 1h and 12h after extubation. RESULTS: Twenty-eight patients were studied. There were no deaths or pulmonary complications. The mean aortic clamping time in the pressure support ventilation group was 62 ± 35 minutes and 68 ± 36 minutes in the T-tube group (P=0.651). The mean cardiopulmonary bypass duration in the pressure-support ventilation group was 89 ± 44 minutes and 82 ± 42 minutes in the T-tube group (P=0.75). The mean Tobin index in the pressure support ventilation group was 51 ± 25 and 64.5 ± 23 in the T-tube group (P=0.153). The duration of intensive care unit stay for the pressure support ventilation group was 2.1 ± 0.36 days and 2.3 ± 0.61 days in the T-tube group (P=0.581). The atelectasis score in the T-tube group was 0.6 ± 0.8 and 0.5 ± 0.6 (P=0.979) in the pressure support ventilation group. The study groups did not differ significantly in manovacuometric and ventilometric parameters and hospital evolution. CONCLUSION: The two trial methods evaluated for interruption of mechanical ventilation did not affect the postoperative course of patients who underwent cardiac operations with cardiopulmonary bypass.

OBJETIVO: Comparar a pressão de suporte ventilatório com a respiração espontânea em "Tubo-T" para interrupção da ventilação invasiva em pacientes submetidos à operação cardíaca. MÉTODOS: Adultos de ambos os sexos foram alocados para pressão de suporte ventilatório por 30 minutos ou o mesmo período de ventilação espontânea com "Tubo-T" antes da extubação. Realizou-se manovacuometria, ventilometria e avaliação clínica antes da operação, imediatamente antes e após a extubação, 1h e 12h após extubação. RESULTADOS: Vinte e oito pacientes foram estudados. Não ocorreram mortes ou complicações respiratórias. O tempo de pinçamento da aorta no grupo suporte ventilatório foi 62 ± 35 minutos e de 68 ± 36 minutos para o "Tubo-T" (P=0,651). O tempo de CEC no grupo suporte ventilatório foi 89 ± 44 minutos e para o "Tubo-T" de 82 ± 42 minutos (P=0,75). O índice de Tobin para o grupo suporte ventilatório foi 51 ± 25 e para o grupo "Tubo-T", 64,5 ± 23 (P=0,153). O tempo na unidade de terapia intensiva para o grupo suporte ventilatório foi 2,1 ± 0,36 dias e para o grupo "Tubo-T", 2,3±0,61 dias (P=0,581). O escore de atelectasia para o grupo "Tubo-T" foi 0,6 ± 0,8 e para o suporte ventilatório foi 0,5 ± 0,6 (P=0,979). Não houve diferença significativa na evolução clínica e nos valores de gasometria, manovacuometria e ventilometria entre ambos os grupos. CONCLUSÃO: O método utilizado para testar a adequação da interrupção da ventilação mecânica invasiva não afetou a evolução pós-operatória dos pacientes submetidos a operações cardíacas com circulação extracorpórea.

The effect of positive-end expiratory pressure on oxygenation during high frequency jet ventilation and conventional mechanical ventilation in the rabbit model of acute lung injury / 대한마취과학회지

BACKGROUND: The use of positive end expiratory pressure (PEEP) in patients with acute lung injury (ALI) improves arterial oxygenation by alleviating pulmonary shunting, helping the respiratory muscles to decrease the work of breathing, decreasing the rate of infiltrated and atelectatic tissues, and increasing functional residual capacity. In a rabbit model of saline lavage-induced ALI, we examined the effects of PEEP on gas exchange, hemodynamics, and oxygenation during high frequency jet ventilation (HFJV), and then compared these parameters with those during conventional mechanical ventilation (CMV). METHODS: Twelve rabbits underwent repeated saline lavage to create ALI. The animals were divided in 2 groups: 1) Group CMV (n = 6), and 2) Group HFJV (n = 6). In both groups, we applied 2 levels of PEEP (5 cmH2O and 10 cmH2O) and then measured the arterial blood gas, mixed venous blood gas, and hemodynamic parameters. RESULTS: With administration of PEEP of either 5 cmH2O or 10 cmH2O, the arterial oxygen content of both groups was increased, although without statistically significant differences between groups. On the contrary, the arterial carbon dioxide content was significantly decreased in the HFJV group, as compared with the CMV group, during the entire experiment. Furthermore, there was significant decreases in mean arterial pressures in both groups with a PEEP of 10 cmH2O. CONCLUSIONS: The application of PEEP in rabbits with ALI effectively improves oxygenation in either HFJV or CMV.

Anaesthetic experience in a patient with severe thoracolumbar kyphosis: A case report

Kyphosis is a deformity characterized by anterior flexion of the vertebral column. When severe, kyphosis may decrease lung volume and compliance, leading to increased work of breathing and deterioration of pulmonary function. Moreover, postoperative respiratory failure is a common problem for patients with severe spinal deformities. We describe the successful case of general anaesthesia in a 71-year-old male patient with severe thoracolumbar kyphosis undergoing open surgery converted from robotic surgery.

Capacidade funcional e força muscular respiratória de candidatos ao transplante hepático / Functional capacity and respiratory muscle strength of candidates to hepatic transplant

INTRODUÇÃO: A doença hepática crônica resulta em grande impacto funcional, causando perda de massa e função muscular com consequente redução da capacidade funcional. OBJETIVO: Avaliar e comparar a força muscular respiratória e a capacidade funcional dos candidatos ao transplante hepático que possuem classe B ou C segundo o Child-Pugh Score e correlacionar estas variáveis dentro de cada grupo. MÉTODOS: Estudo transversal, com amostra de conveniência composta por 35 pacientes, divididos em dois grupos a partir da pontuação obtida no Child-Pugh Score, sendo B (19 pacientes) e C (16 pacientes). Todos os indivíduos foram avaliados em um único momento, sendo mensuradas as pressões inspiratória máxima (PImáx) e expiratória máxima (PEmáx) e a distância percorrida no teste de caminhada de seis minutos (TC6M). RESULTADOS: Os indivíduos classificados com Child-Pugh Score B apresentaram maiores valores na PImáx (-86,05 ± 23,89 vs. -57,94 ± 14,14), p = 0,001, na PEmáx (84,16 ± 28,26 vs. 72,00 ± 16,94), p = 0,142, e na distância percorrida no TC6M (473,63 ± 55,276 vs. 376,13 ± 39,00), p = 0,001. Encontramos, ainda, correlação positiva entre os valores da PImáx e a distância percorrida no TC6M dentro grupo Child-Pugh Score B, r = 0,64 e p = 0,003. CONCLUSÃO: O progresso da doença hepática contribui para o surgimento de diversas complicações que, em conjunto, parecem contribuir para a redução da capacidade funcional dos indivíduos. Em nosso trabalho, isso ficou evidenciado pelo pior desempenho do grupo Child-Pugh Score C. Isto pode sugerir que a espera para o transplante hepático (TxH) pode agravar a capacidade funcional e a força muscular respiratória desses indivíduos.

INTRODUCTION: Chronic liver disease results in large functional impact, causing loss of muscle mass and function with consequent reduction of functional capacity. OBJECTIVE: To evaluate and compare the respiratory muscle strength and functional capacity of candidates for liver transplantation who are under Class B or C according to Child Pugh Score and to correlate these variables within each group. METHODS- Cross-sectional study with a convenience sample of 35 patients divided into two groups based on the score obtained in the Child Pugh Score B (19 patients) and Child Pugh Score C (16 patients). All subjects were evaluated in a single moment, and the maximal inspiratory pressure (MIP) and maximal expiratory pressure (MEP) as well as the distance walked during the 6-minute walk test (6MWT) were measured. RESULTS: Individuals classified with Child Pugh Score B showed higher values in the MIP (- 86.05 vs. 23.89 - 57.94 14.14), p = 0.001, in MEP (84.16 vs. 28.26 72.00 16 1994), p = 0.142, and the distance walked in 6MWT (473.63 vs 376.13 39.00 55.276), p = 0.001. We also found a positive correlation between the values of MIP and distance walked during 6MWT in group B of the Child Pugh Score, r = 0.64 and p = 0.003. CONCLUSION: The progress of liver disease contributes to the onset of several complications, which together appear to contribute to the reduction of functional capacity of individuals. In our study this was evidenced by the worse performance of Child Pugh score C group. This may suggest that the wait for liver transplantation (LTx) can worsen the functional capacity of these individuals.

Influência do choro e de padrões respiratórios na deposição de medicação inalatória em crianças / The influence of crying and breathing pattern on inhalatory drug deposition in children

OBJETIVO: Verificar a influência do choro e de padrões respiratórios na eficácia da terapia inalatória em crianças. FONTES DE DADOS: busca sistemática por artigos científicos referentes ao tema nas bases de dados Cochrane Controlled Trials Data Base, MedLine e Science Direct, publicadas no período de 1994 a 2009. Utilizaram-se os descritores: "choro", "inalação", "aerossol", "trabalho respiratório" e "criança", nos idiomas português e inglês. SÍNTESE DE DADOS: Foram selecionados 13 artigos, 12 em inglês e um em português. A maioria dos trabalhos apresenta os efeitos da terapia inalatória em crianças, sem discutir a influência do choro e de diferentes padrões respiratórios sobre a deposição da medicação. Estudos que fizeram essa relação verificaram que a respiração e, principalmente, o choro reduzem a quantidade de fármaco que chega às vias aéreas periféricas. Autores discutem as diferenças anatômicas e fisiológicas do sistema respiratório da criança que podem interferir na eficácia da terapia inalatória. Porém, a maioria deles não analisa a influência qualitativa e quantitativa dos padrões respiratórios e do choro sobre a mecânica pulmonar. CONCLUSÕES: O choro e os padrões respiratórios influenciam na terapia inalatória, sendo atribuída ao choro a redução significativa da deposição medicamentosa nas vias aéreas. Pouco se sabe sobre o princípio determinante para a alteração do potencial de deposição, pois são escassas as evidências sobre o tema, apesar de sua relevância no manejo de afecções pulmonares da população pediátrica.

OBJECTIVE: To verify the influence of crying and breathing patterns in the effectiveness of inhalatory therapy in children. DATA SOURCES: Systematic search of scientific studies on the subject in the Cochrane Controlled Trials Database, MedLine and Science Direct, published from 1994 to 2009. The descriptors "crying", "inhalation", "aerosol", "work of breathing" and "child", in Portuguese and in English, were applied. DATA SYNTHESIS: 13 studies were selected, 12 in English and one in Portuguese. Most studies reported the effects of inhalation therapy in children, without discussing the influence of crying and breathing patterns on the deposition of the medication. Studies related to this subject found that the respiratory pattern, especially the cry, reduces the amount of drug that reaches the peripheral airways. Authors discuss the anatomical and physiological differences between adults' and children's respiratory system that may interfere with the effectiveness of inhalation. However, most of them do not examine the qualitative and quantitative influence of the breathing patterns and crying on pulmonary mechanics. CONCLUSIONS: Crying and breathing patterns influence the inhalation therapy. The presence of cry significantly reduces the amount of drug deposition in the airways. There is insufficient evidence about the possible mechanisms that explain potential changes of inhalatory drugs deposition in children, despite its relevance to the management of pediatric pulmonary disorders.

Interação paciente ventilador nas diferentes fases do ciclo ventilatório em ventilação por pressão de suporte / Patient-ventilator interaction on different phases of mechanical breath in pressure support ventilation

Introdução: O principal objetivo da ventilação mecânica é a diminuição do trabalho respiratório. Para que isto ocorra, o ciclo mecânico deveria coincidir com o tempo inspiratório neural do paciente. A assincronia paciente ventilador ocorre por fatores relacionados ao paciente e aos parâmetros ventilatórios e podem prolongar o tempo de suporte mecânico e permanência em unidades de terapia intensiva. Objetivos: Revisar a assincronia nas diferentes fases do ciclo respiratório, sua avaliação através dos gráficos e as intervenções capazes de melhorar a interação paciente ventilador em ventilação por pressão de suporte. Resultados/ Discussão: Através de busca em base de dados científicos, foram incluídos 26 artigos que abordavam o tema proposto. Os diferentes tipos de assincronia podem ser observados através de esforços ineficientes, atrasos no disparo, disparos automáticos, disparos duplos, presença de PEEP intrínseca, términos prematuro ou prolongado da inspiração e curvas diferentes do padrão usual. Conclusão: A correta identificação e ajustes conforme a demanda do paciente são pontos importantes na interação paciente ventilador e podem contribuir para a melhora do prognóstico destes pacientes.(AU)

Introduction: The main reason of mechanical ventilation is the decrease the work of breathing. To achieve it, the mechanical breath should coincide with the neural inspiratory time. Patient-ventilator asynchrony may be secondary for the facts related to the patient´s condition or ventilatory settings and may prolong support and UTI stay. Objectives: Review asynchrony in different phases of mechanical breath, the evaluation through ventilator waveforms and the proper settings to improve patient-ventilator interaction in pressure support ventilation. Results/ Discussion: Through research on scientific basis, 26 studies that match the theme were included. Asynchrony may be seen as inefficient efforts, trigger delay, auto-triggering, double triggering, presence of auto-PEEP, premature termination, delayed termination or unusual waveforms. Conclusion: Proper identification and adjustments that coincides with patient´s demand are critical points in patient ventilator interaction and may contribute to improve their prognosis.(AU)

Skeletal Muscle Dysfunction in Patients with Chronic Obstructive Pulmonary Disease / 결핵및호흡기질환

Patients with chronic obstructive pulmonary disease (COPD) frequently complain of dyspnea on exertion and reduced exercise capacity, which has been attributed to an increase in the work of breathing and in impaired of gas exchange. Although COPD primarily affects the pulmonary system, patients with COPD exhibit significant systemic manifestations of disease progression. These manifestations include weight loss, nutritional abnormalities, skeletal muscle dysfunction (SMD), cardiovascular problems, and psychosocial complications. It has been documented that SMD significantly contributes to a reduced exercise capacity in patients with COPD. Ventilatory and limb muscle in these patients show structural and functional alteration, which are influenced by several factors, including physical inactivity, hypoxia, smoking, aging, corticosteroid, malnutrition, systemic inflammation, oxidative stress, apoptosis, and ubiquitin-proteasome pathway activation. This article summarizes briefly the evidence and the clinical consequences of SMD in patients with COPD. In addition, it reviews contributing factors and therapeutic strategies.

Avaliação do padrão respiratório com base no índice diafragmático obtido pela biofotogrametria computadorizada / Assessment of respiratory pattern through diaphragmatic index using computerized biophotometer

Objetivo: Este estudo teve como objetivo avaliar o padrão respiratório por meio do índice diafragmático obtido pela biofotogrametria computadorizada. Material e métodos: Foram selecionados quarenta voluntários sadios, 20 homens e 20 mulheres, faixa etária entre 18 e 25 anos. As medidas que classificou os índices para o padrão respiratório foram obtidas em três momentos: repouso, inspiração e expiração máxima, na posição ortostática, em vista anterior e perfis. Os valores obtidos na cirtometria possibilitaram classificar o índice diafragmático (ID) pela fórmula: ID = ∆ AB/∆ AB + ∆ CT. Para obtenção dos valores da biofotogrametria computadorizada, foi necessário registrar as imagens dos voluntários com pontos previamente demarcados no tórax e abdome por meio de uma câmera digital que permitiu a quantificação angular com auxílio do software ALCimage2.1. Resultados: Com os dados obtidos pela biofotogrametria, foi possível classificar o índice diafragmático (ID) pela fórmula: ID = - 1.04255 + 0,01969 x a3 exp per esq – 0,03461 x a1 exp per dir – 0.10782 x a2 exp per dir – Índice Diafragmático segundo GDLV (Godoy, Deloroso, Lautenschlaeger e Veloso). Conclusão: Observamos neste estudo uma existente correlação entre os dados do padrão respiratório e os da biofotogrametria, podendo sim avaliar o índice diafragmático através da biofotogrametria aplicando a fórmula ID de GDLV.

Objective: The aim of this study was to assess the respiratory pattern through diaphragmatic index (DI) by computerized biophotometer. Methods: Forty health young individuals were studied, 20 male and 20 female, aged group between 18 to 25 years old. The measurements were taken in orthostatic position at three different points: at rest, maximal inspiration and maximal expiration on anterior and lateral position. The obtained values through cirtometry enable us to classify the diaphragmatic index using the following formula: DI = ∆ AB/∆ AB + ∆ CT. In order to obtain the computerized biophotometer values, the individuals were demarcated in the chest and abdomen and using a digital camera their images were registered and for the quantification of the angle it was used the software ALCimage2.1. Results: After collecting biophotometer data, the diaphragmatic index (ID) was classified by formula: DI = - 1.04255 + 0.01969 x exp a3 per esq - 0.03461 x a1 exp per say - a2 x exp 0.10782 per dir (Diaphragmatic Index according to GDLV (Godoy, Deloroso, Lautenschlaeger and Veloso). Conclusion: It was observed, in this study, that there is a correlation between data of the respiratory pattern and of the biophotometer, and it was possible to evaluate the diaphragmatic index using DI formula of GDLV.

Research on a new method to trigger ventilator based on electromyogram / 生物医学工程学杂志

In order to improve synchrony between a ventilator and its patient, a new method for triggering a ventilator based on diaphragmatic electromyogram (EMG) is introduced. The methods to extract and process diaphragmatic EMG signals are studied. It has been shown that the characteristic parameters of a respiration activity, such as inspiratory beginning point, expiratory beginning point and respiration period, can be detected from diaphragmatic EMG envelop instead of traditional flux curve. A new parameter, designated as diaphragmatic "Intensity of EMG" for short "IEMG", is defined. Repeat respiration tests have disclosed that there is relatively high correlation between the diaphragmatic IEMG curve and its corresponding cubage curve. These results primarily demonstrate that the new synchronization method may be feasible.

Short-term effects of positive expiratory airway pressure in patients being weaned from mechanical ventilation

OBJECTIVE: To investigate the feasibility and the cardiorespiratory effects of using positive expiratory airway pressure, a physiotherapeutic tool, in comparison with a T-tube, to wean patients from mechanical ventilation. METHODS/DESIGN: A prospective, randomized, cross-over study. SETTING: Two intensive care units. PATIENTS AND INTERVENTIONS: We evaluated forty patients who met weaning criteria and had been mechanically-ventilated for more than 48 hours, mean age 59 years, including 23 males. All patients were submitted to the T-tube and Expiratory Positive Airway Pressure devices, at 7 cm H2O, during a 30-minute period. Cardiorespiratory variables including work of breathing, respiratory rate (rr), peripheral oxygen saturation (SpO2), heart rate (hr), systolic, diastolic and mean arterial pressures (SAP, DAP, MAP) were measured in the first and thirtieth minutes. The condition was analyzed as an entire sample set (n=40) and was also divided into subconditions: chronic obstructive pulmonary disease (n=14) and non-chronic obstructive pulmonary disease (non- chronic obstructive pulmonary disease) (n=26) categories. Comparisons were made using a t-test and Analysis of Variance. The level of significance was p < 0.05. RESULTS: Our data showed an increase in work of breathing in the first and thirtieth minutes in the EPAP condition (0.86+ 0.43 and 1.02+1.3) as compared with the T-tube condition (0.25+0.26 and 0.26+0.35) (p<0.05), verified by the flow-sensor monitor (values in J/L). No statistical differences were observed when comparing the Expiratory Positive Airway Pressure and T-tube conditions with regard to cardiorespiratory measurements. The same result was observed for both chronic obstructive pulmonary disease and non- chronic obstructive pulmonary disease subconditions. CONCLUSIONS: Our study demonstrated that, in weaning patients from mechanical ventilation, the use of a fixed level of Expiratory Positive Airway Pressure caused ...