Ventilator hyperinflation associated with flow bias optimization in the bronchial hygiene of mechanically ventilated patients.

BACKGROUND: Ventilation configurations are of great clinical importance for adequate outcomes in mechanically ventilated patients, and they may even be used as specific physical therapy techniques. OBJECTIVES: To compare the effectiveness of lung hyperinflation through mechanical ventilation (HMV) with HMV plus flow bias optimization regarding respiratory mechanics, hemodynamics, and volume of secretion. METHODS: Patients mechanically ventilated > 24 h were included in this randomized crossover clinical trial. The following techniques were applied: HMV alone (control group) and HMV plus flow bias optimization (intervention group). RESULTS: The 20 included patients underwent both techniques, totaling 40 collections. A total of 52 % were women, the mean age was 60.8 (SD, 15.7) years, and the mean mechanical ventilation time was 4.3 (SD, 3.0) days. The main cause of mechanical ventilation was sepsis (44 %). Expiratory flow bias in optimized HMV was higher. than conventional HMV (p < 0.001). The volume of tracheal secretions collected was higher during optimized than conventional HMV. (p = 0.012). Significant differences in peak flow occurred at the beginning of the technique and a there was a significant decrease in respiratory system resistance immediately and 30 min after applying the technique in the intervention group. CONCLUSIONS: The volume of tracheal secretions collected was higher during optimized HMV, and, HMV with flow bias optimization resulted in lower respiratory system resistance and flow peaks and produced expiratory flow bias.

A comprehensive physical functional assessment of survivors of critical care unit stay due to COVID-19.

OBJECTIVE: To examine the physical function and respiratory muscle strength of patients - who recovered from critical COVID-19 - after intensive care unit discharge to the ward on Days one (D1) and seven (D7), and to investigate variables associated with functional impairment. METHODS: This was a prospective cohort study of adult patients with COVID-19 who needed invasive mechanical ventilation, non-invasive ventilation or high-flow nasal cannula and were discharged from the intensive care unit to the ward. Participants were submitted to Medical Research Council sum-score, handgrip strength, maximal inspiratory pressure, maximal expiratory pressure, and short physical performance battery tests. Participants were grouped into two groups according to their need for invasive ventilation: the Invasive Mechanical Ventilation Group (IMV Group) and the Non-Invasive Mechanical Ventilation Group (Non-IMV Group). RESULTS: Patients in the IMV Group (n = 31) were younger and had higher Sequential Organ Failure Assessment scores than those in the Non-IMV Group (n = 33). The short physical performance battery scores (range 0 - 12) on D1 and D7 were 6.1 ± 4.3 and 7.3 ± 3.8, respectively for the Non-Invasive Mechanical Ventilation Group, and 1.3 ± 2.5 and 2.6 ± 3.7, respectively for the IMV Group. The prevalence of intensive care unit-acquired weakness on D7 was 13% for the Non-IMV Group and 72% for the IMV Group. The maximal inspiratory pressure, maximal expiratory pressure, and handgrip strength increased on D7 in both groups, but the maximal expiratory pressure and handgrip strength were still weak. Only maximal inspiratory pressure was recovered (i.e., > 80% of the predicted value) in the Non-IMV Group. Female sex, and the need and duration of invasive mechanical were independently and negatively associated with the short physical performance battery score and handgrip strength. CONCLUSION: Patients who recovered from critical COVID-19 and who received invasive mechanical ventilation presented greater disability than those who were not invasively ventilated. However, they both showed marginal functional improvement during early recovery, regardless of the need for invasive mechanical ventilation. This might highlight the severity of disability caused by SARS-CoV-2.

Chest physiotherapy techniques administered by certified specialists to hospitalized patients with COVID-19 in Brazil: A look towards future practice.

BACKGROUND: Chest physiotherapy for hospitalized patients with COVID-19 has been poorly reported. Although recommendations were published to guide physiotherapists, practice might have differed depending on education and training. OBJECTIVE: To analyze the differences in chest physiotherapy applied for hospitalized patients with COVID-19 between certified specialists and non-certified specialists. METHODS: An online questionnaire survey was developed for physiotherapists involved in the management of hospitalized patients with COVID-19. The questionnaire inquired about professional information and characteristics of physiotherapy practice. RESULTS: There were 485 respondents, yielding a completion rate of 76%. Of these, 61 were certified specialists and 424 non-certified specialists. The certified specialists were older, had more years of professional experience, were more qualified, and had better job conditions. For mechanically ventilated patients, the certified specialists used the ventilator hyperinflation maneuver more frequently (50.4% vs 35.1%, p = 0.005), and the hard/brief expiratory rib cage compression (ERCC) (26.9% vs 48.3%, p = 0.016), soft/long ERCC (25.2% vs 39.1%, p = 0.047), and manual chest compression-decompression (MCCD) maneuver (22.4% vs 35.6%, p = 0.001) less often. For spontaneously breathing patients, the certified specialists used the active cycle of breathing technique (30.8% vs 67.1%, p<0.001), autogenic drainage (7.7% vs 20.7%, p = 0.017), and MCCD maneuver (23.1% vs 41.4%, p = 0.018) less frequently. CONCLUSIONS: Certified specialists with higher levels of expertise seem to prefer the use of chest physiotherapy techniques that are applied with the mechanical ventilator over manual techniques. Furthermore, they use techniques that could potentially increase the work of breathing less frequently, mitigating the risk of exacerbating respiratory conditions in patients with COVID-19.

Physiotherapy practice for hospitalized patients with COVID-19.

OBJECTIVE: To identify the indications for physiotherapy and to evaluate physiotherapy practices in patients with COVID-19 admitted to the ICU (on mechanical ventilation) or to the ward (spontaneously breathing). METHODS: An online, 50-item survey was completed by physiotherapists who had been treating hospitalized patients with COVID-19 in Brazil. RESULTS: Of the 644 physiotherapists who initiated the survey, 488 (76%) completed it. The main reasons for indications for physiotherapy in both settings reported as "very frequently" and "frequently" both in the ICU and the ward by most respondents were oxygenation improvement (> 95%) and prevention of general complications (> 83%). Physical deconditioning was considered an infrequent indication. When compared with mobilization strategies, the use of respiratory interventions showed great variability in both work settings, and techniques considered effective were underutilized. The most frequently used respiratory techniques in the ICU were positioning (86%), alveolar recruitment (73%), and hard/brief expiratory rib cage compression (46%), whereas those in the ward were active prone positioning (90%), breathing exercises (88%), and directed/assisted cough (75%). The mobilization interventions reported by more than 75% of the respondents were sitting on the edge of the bed, active and resistive range of motion exercises, standing, ambulation, and stepping in place. CONCLUSIONS: The least common reason for indications for physiotherapy was avoidance of deconditioning, whereas oxygenation improvement was the most frequent one. Great variability in respiratory interventions was observed when compared with mobilization therapies, and there is a clear need to standardize respiratory physiotherapy treatment for hospitalized patients with COVID-19.

Effects of Mechanical Insufflation-Exsufflation With Different Pressure Settings on Respiratory Mucus Displacement During Invasive Ventilation.

BACKGROUND: Mechanical insufflation-exsufflation (MI-E) has been proposed as a potential strategy to generate high expiratory flows and simulate cough in the critically ill. However, efficacy and safety of MI-E during invasive mechanical ventilation are still to be fully elucidated. This study in intubated and mechanically ventilated pigs aimed to evaluate the effects of 8 combinations of insufflation-exsufflation pressures during MI-E on mucus displacement, respiratory flows, as well as respiratory mechanics and hemodynamics. METHODS: Six healthy Landrace-Large White female pigs were orotracheally intubated, anesthetized, and invasively ventilated for up to 72 h. Eight combinations of insufflation-exsufflation pressures (+40/-40, +40/-50, +40/-60, +40/-70, +50/-40, +50/-50, +50/-60, +50/-70 cm H2O) were applied in a randomized order. The MI-E device was set to automatic mode, medium inspiratory flow, and an inspiratory-expiratory time 3 and 2 s, respectively, with a 1-s pause between cycles. We performed 4 series of 5 insufflation-exsufflation cycles for each combination of pressures. Velocity and direction of movement of a mucus simulant containing radio-opaque markers were assessed through sequential lateral fluoroscopic images of the trachea. We also evaluated respiratory flows, respiratory mechanics, and hemodynamics before, during, and after each combination of pressures. RESULTS: In 3 of the animals, experiments were conducted twice; and for the remaining 3, they were conducted once. In comparison to baseline mucus movement (2.85 ± 2.06 mm/min), all insufflation-exsufflation pressure combinations significantly increased mucus velocity (P = .01). Particularly, +40/-70 cm H2O was the most effective combination, increasing mucus movement velocity by up to 4.8-fold (P < .001). Insufflation pressure of +50 cm H2O resulted in higher peak inspiratory flows (P = .004) and inspiratory transpulmonary pressure (P < .001) than +40 cm H2O. CONCLUSIONS: MI-E appeared to be an efficient strategy to improve mucus displacement during invasive ventilation, particularly when set at +40/-70 cm H2O. No safety concerns were identified although a transient significant increase of transpulmonary pressure was observed.

Protective mechanical ventilation in suspected influenza infection.

INTRODUCTION: Patients with acute respiratory failure due to influenza require ventilatory support. However, mechanical ventilation itself can exacerbate lung damage and increase mortality. METHODS: The aim of this study was to describe a feasible and protective ventilation protocol, with limitation of the tidal volume to ≤6 mL/kg of the predicted weight and a driving pressure ≤15 cmH2O after application of the alveolar recruitment maneuver and PEEP titration. RESULTS: Initial improvement in oxygenation and respiratory mechanics were observed in the four cases submitted to the proposed protocol. CONCLUSIONS: Our results indicate that the mechanical ventilation strategy applied could be optimized.

Effects of manual chest compression on expiratory flow bias during the positive end-expiratory pressure-zero end-expiratory pressure maneuver in patients on mechanical ventilation.

OBJECTIVE: To investigate the effects of manual chest compression (MCC) on the expiratory flow bias during the positive end-expiratory pressure-zero end-expiratory pressure (PEEP-ZEEP) airway clearance maneuver applied in patients on mechanical ventilation. The flow bias, which influences pulmonary secretion removal, is evaluated by the ratio and difference between the peak expiratory flow (PEF) and the peak inspiratory flow (PIF). METHODS: This was a crossover randomized study involving 10 patients. The PEEP-ZEEP maneuver was applied at four time points, one without MCC and the other three with MCC, which were performed by three different respiratory therapists. Respiratory mechanics data were obtained with a specific monitor. RESULTS: The PEEP-ZEEP maneuver without MCC was enough to exceed the threshold that is considered necessary to move secretion toward the glottis (PEF - PIF difference > 33 L/min): a mean PEF - PIF difference of 49.1 ± 9.4 L/min was achieved. The mean PEF/PIF ratio achieved was 3.3 ± 0.7. Using MCC with PEEP-ZEEP increased the mean PEF - PIF difference by 6.7 ± 3.4 L/min. We found a moderate correlation between respiratory therapist hand grip strength and the flow bias generated with MCC. No adverse hemodynamic or respiratory effects were found. CONCLUSIONS: The PEEP-ZEEP maneuver, without MCC, resulted in an expiratory flow bias superior to that necessary to facilitate pulmonary secretion removal. Combining MCC with the PEEP-ZEEP maneuver increased the expiratory flow bias, which increases the potential of the maneuver to remove secretions.

A comprehensive physical functional assessment of survivors of critical care unit stay due to COVID-19 / Avaliação físico-funcional abrangente de sobreviventes de internação em unidade de terapia intensiva devido à COVID-19

ABSTRACT Objective: To examine the physical function and respiratory muscle strength of patients - who recovered from critical COVID-19 - after intensive care unit discharge to the ward on Days one (D1) and seven (D7), and to investigate variables associated with functional impairment. Methods: This was a prospective cohort study of adult patients with COVID-19 who needed invasive mechanical ventilation, non-invasive ventilation or high-flow nasal cannula and were discharged from the intensive care unit to the ward. Participants were submitted to Medical Research Council sum-score, handgrip strength, maximal inspiratory pressure, maximal expiratory pressure, and short physical performance battery tests. Participants were grouped into two groups according to their need for invasive ventilation: the Invasive Mechanical Ventilation Group (IMV Group) and the Non-Invasive Mechanical Ventilation Group (Non-IMV Group). Results: Patients in the IMV Group (n = 31) were younger and had higher Sequential Organ Failure Assessment scores than those in the Non-IMV Group (n = 33). The short physical performance battery scores (range 0 - 12) on D1 and D7 were 6.1 ± 4.3 and 7.3 ± 3.8, respectively for the Non-Invasive Mechanical Ventilation Group, and 1.3 ± 2.5 and 2.6 ± 3.7, respectively for the IMV Group. The prevalence of intensive care unit-acquired weakness on D7 was 13% for the Non-IMV Group and 72% for the IMV Group. The maximal inspiratory pressure, maximal expiratory pressure, and handgrip strength increased on D7 in both groups, but the maximal expiratory pressure and handgrip strength were still weak. Only maximal inspiratory pressure was recovered (i.e., > 80% of the predicted value) in the Non-IMV Group. Female sex, and the need and duration of invasive mechanical were independently and negatively associated with the short physical performance battery score and handgrip strength. Conclusion: Patients who recovered from critical COVID-19 and who received invasive mechanical ventilation presented greater disability than those who were not invasively ventilated. However, they both showed marginal functional improvement during early recovery, regardless of the need for invasive mechanical ventilation. This might highlight the severity of disability caused by SARS-CoV-2.

RESUMO Objetivo: Examinar a função física e a força muscular respiratória de pacientes que se recuperaram da COVID-19 grave após a alta da unidade de terapia intensiva para a enfermaria nos Dias 1 e 7 e investigar as variáveis associadas ao comprometimento funcional. Métodos: Trata-se de estudo de coorte prospectivo de pacientes adultos com COVID-19 que necessitaram de ventilação mecânica invasiva, ventilação mecânica não invasiva ou cânula nasal de alto fluxo e tiveram alta da unidade de terapia intensiva para a enfermaria. Os participantes foram submetidos aos testes Medical Research Council sum-score, força de preensão manual, pressão inspiratória máxima, pressão expiratória máxima e short physical performance battery. Os participantes foram agrupados em dois grupos conforme a necessidade de ventilação mecânica invasiva: o Grupo Ventilação Mecânica Invasiva (Grupo VMI) e o Grupo Não Ventilação Mecânica Invasiva (Grupo Não VMI). Resultados: Os pacientes do Grupo VMI (n = 31) eram mais jovens e tinham pontuações do Sequential Organ Failure Assessment mais altas do que os do Grupo VMI (n = 33). As pontuações do short physical performance battery (intervalo de zero a 12) nos Dias 1 e 7 foram 6,1 ± 4,3 e 7,3 ± 3,8, respectivamente para o Grupo Não VMI, e 1,3 ± 2,5 e 2,6 ± 3,7, respectivamente para o Grupo VMI. A prevalência de fraqueza adquirida na unidade de terapia intensiva no Dia 7 foi de 13% para o Grupo Não VMI e de 72% para o Grupo VMI. A pressão inspiratória máxima, a pressão expiratória máxima e a força de preensão manual aumentaram no Dia 7 em ambos os grupos, porém a pressão expiratória máxima e a força de preensão manual ainda eram fracas. Apenas a pressão inspiratória máxima foi recuperada (ou seja, > 80% do valor previsto) no Grupo Não VMI. As variáveis sexo feminino, e necessidade e duração da ventilação mecânica invasiva foram associadas de forma independente e negativa à pontuação do short physical performance battery e à força de preensão manual. Conclusão: Os pacientes que se recuperaram da COVID-19 grave e receberam ventilação mecânica invasiva apresentaram maior incapacidade do que aqueles que não foram ventilados invasivamente. No entanto, os dois grupos de pacientes apresentaram melhora funcional marginal durante a fase inicial de recuperação, independentemente da necessidade de ventilação mecânica invasiva. Esse resultado pode evidenciar a gravidade da incapacidade causada pelo SARS-CoV-2.

Physiotherapy practice for hospitalized patients with COVID-19 / Prática fisioterapêutica para pacientes hospitalizados com COVID-19

ABSTRACT Objective: To identify the indications for physiotherapy and to evaluate physiotherapy practices in patients with COVID-19 admitted to the ICU (on mechanical ventilation) or to the ward (spontaneously breathing). Methods: An online, 50-item survey was completed by physiotherapists who had been treating hospitalized patients with COVID-19 in Brazil. Results: Of the 644 physiotherapists who initiated the survey, 488 (76%) completed it. The main reasons for indications for physiotherapy in both settings reported as "very frequently" and "frequently" both in the ICU and the ward by most respondents were oxygenation improvement (> 95%) and prevention of general complications (> 83%). Physical deconditioning was considered an infrequent indication. When compared with mobilization strategies, the use of respiratory interventions showed great variability in both work settings, and techniques considered effective were underutilized. The most frequently used respiratory techniques in the ICU were positioning (86%), alveolar recruitment (73%), and hard/brief expiratory rib cage compression (46%), whereas those in the ward were active prone positioning (90%), breathing exercises (88%), and directed/assisted cough (75%). The mobilization interventions reported by more than 75% of the respondents were sitting on the edge of the bed, active and resistive range of motion exercises, standing, ambulation, and stepping in place. Conclusions: The least common reason for indications for physiotherapy was avoidance of deconditioning, whereas oxygenation improvement was the most frequent one. Great variability in respiratory interventions was observed when compared with mobilization therapies, and there is a clear need to standardize respiratory physiotherapy treatment for hospitalized patients with COVID-19.

RESUMO Objetivo: Identificar as indicações de fisioterapia e avaliar as práticas fisioterapêuticas em pacientes com COVID-19 internados na UTI (em ventilação mecânica) ou na enfermaria (em respiração espontânea). Métodos: Questionário online, com 50 questões, respondido por fisioterapeutas que atendiam pacientes hospitalizados com COVID-19 no Brasil. Resultados: Dos 644 fisioterapeutas que iniciaram o questionário, 488 (76%) o concluíram. As principais indicações de fisioterapia relatadas como "muito frequente" e "frequentemente" tanto na UTI quanto na enfermaria pela maioria dos respondentes foram melhora da oxigenação (> 95%) e prevenção de complicações gerais (> 83%). Descondicionamento físico foi considerado uma indicação pouco frequente. Em comparação com as estratégias de mobilização, as intervenções respiratórias apresentaram grande variabilidade em ambos os setores de trabalho, e técnicas consideradas eficazes foram subutilizadas. As técnicas respiratórias mais utilizadas na UTI foram posicionamento (86%), recrutamento alveolar (73%) e compressão torácica expiratória forte e rápida (46%), enquanto, na enfermaria, as mais utilizadas foram posição prona ativa (90%), exercícios respiratórios (88%) e tosse assistida/dirigida (75%). As intervenções de mobilização relatadas por mais de 75% dos respondentes foram sedestação a beira leito, exercícios ativos e resistidos de membros superiores/inferiores, ortostatismo, deambulação e marcha estacionária. Conclusões: A indicação menos frequente de fisioterapia foi prevenção do descondicionamento, enquanto melhora da oxigenação foi a mais frequente. Observou-se grande variabilidade nas intervenções respiratórias em comparação com as terapias de mobilização, e há uma clara necessidade de padronização do tratamento fisioterapêutico respiratório para pacientes hospitalizados com COVID-19.

Protective mechanical ventilation in suspected influenza infection

Abstract INTRODUCTION: Patients with acute respiratory failure due to influenza require ventilatory support. However, mechanical ventilation itself can exacerbate lung damage and increase mortality. METHODS: The aim of this study was to describe a feasible and protective ventilation protocol, with limitation of the tidal volume to ≤6 mL/kg of the predicted weight and a driving pressure ≤15 cmH2O after application of the alveolar recruitment maneuver and PEEP titration. RESULTS: Initial improvement in oxygenation and respiratory mechanics were observed in the four cases submitted to the proposed protocol. CONCLUSIONS: Our results indicate that the mechanical ventilation strategy applied could be optimized.

Effects of manual chest compression on expiratory flow bias during the positive end-expiratory pressure-zero end-expiratory pressure maneuver in patients on mechanical ventilation / Efeitos da compressão torácica manual sobre o flow bias expiratório durante a manobra positive end-expiratory pressure-zero end-expiratory pressure em pacientes sob ventilação mecânica invasiva

ABSTRACT Objective: To investigate the effects of manual chest compression (MCC) on the expiratory flow bias during the positive end-expiratory pressure-zero end-expiratory pressure (PEEP-ZEEP) airway clearance maneuver applied in patients on mechanical ventilation. The flow bias, which influences pulmonary secretion removal, is evaluated by the ratio and difference between the peak expiratory flow (PEF) and the peak inspiratory flow (PIF). Methods: This was a crossover randomized study involving 10 patients. The PEEP-ZEEP maneuver was applied at four time points, one without MCC and the other three with MCC, which were performed by three different respiratory therapists. Respiratory mechanics data were obtained with a specific monitor. Results: The PEEP-ZEEP maneuver without MCC was enough to exceed the threshold that is considered necessary to move secretion toward the glottis (PEF − PIF difference > 33 L/min): a mean PEF − PIF difference of 49.1 ± 9.4 L/min was achieved. The mean PEF/PIF ratio achieved was 3.3 ± 0.7. Using MCC with PEEP-ZEEP increased the mean PEF − PIF difference by 6.7 ± 3.4 L/min. We found a moderate correlation between respiratory therapist hand grip strength and the flow bias generated with MCC. No adverse hemodynamic or respiratory effects were found. Conclusions: The PEEP-ZEEP maneuver, without MCC, resulted in an expiratory flow bias superior to that necessary to facilitate pulmonary secretion removal. Combining MCC with the PEEP-ZEEP maneuver increased the expiratory flow bias, which increases the potential of the maneuver to remove secretions.

RESUMO Objetivo: Avaliar os efeitos da compressão torácica manual (CTM) sobre o flow bias expiratório durante a manobra positive end-expiratory pressure-zero end-expiratory pressure (PEEP-ZEEP) para a remoção de secreção em pacientes sob ventilação mecânica invasiva. O flow bias, que influencia na remoção de secreção pulmonar, foi avaliado pela razão e diferença entre pico de fluxo expiratório (PFE) e pico de fluxo inspiratório (PFI). Métodos: Estudo cruzado e randomizado no qual participaram 10 pacientes. A manobra PEEP-ZEEP foi aplicada em quatro momentos, sendo um sem CTM e os outros três em associação com a CTM, que foram aplicadas por três fisioterapeutas distintos. Um monitor específico foi utilizado para o registro dos dados de mecânica respiratória. Resultados: A manobra PEEP-ZEEP sem a CTM foi suficiente para ultrapassar o limiar do flow bias expiratório (diferença PFE − PFI > 33 l/min), considerado necessário para deslocar a secreção em direção à glote; a média da diferença PFE − PFI encontrada foi de 49,1 ± 9,4 l/min. A média da razão PFE/PFI alcançada foi de 3,3 ± 0,7. A associação da CTM à PEEP-ZEEP aumentou a média da diferença PFE − PFI em 6,7 ± 3,4 l/min. Foi observada correlação moderada entre a força de preensão manual dos fisioterapeutas e o flow bias gerado durante a CTM. Não foram encontradas alterações hemodinâmicas ou respiratórias adversas ao longo do estudo. Conclusões: A manobra PEEP-ZEEP sem a CTM resultou em um flow bias expiratório superior ao considerado efetivo para auxiliar na remoção de secreção pulmonar. A associação com a CTM aumentou o flow bias expiratório, o que aumenta o potencial da manobra para remover secreções.

Eficácia do treinamento muscular inspiratório pré-operatório utilizando o Threshold IMT em pacientes submetidos à cirurgia esofágica: um ensaio clínico randomizado / Effectiveness of preoperative inspiratory muscle training using the Threshold IMT in patients undergoing esophageal surgery: a randomized clinical trial

INTRODUÇÃO: O treinamento muscular inspiratório (TMI) no pré-operatório pode evitar complicações pulmonares no pós-operatório (CPPO) em pacientes submetidos a esofagectomia. OBJETIVO: Avaliar a eficácia do TMI que foi realizado no período pré-operatório e seus benefícios no período pós-operatório, através da avaliação da pressão inspiratória máxima (PImáx), da pressão expiratória máxima (PEmáx), da ventilação voluntária máxima (VVM) e do pico de fluxo expiratório (PFE) e os benefícios do mesmo no pós-operatório. MATERIAIS E MÉTODOS: Foi realizado um ensaio clínico, randomizado, que foi realizado pela disciplina de Cirurgia do Aparelho Digestivo do Hospital das Clínicas da Universidade Federal do Triângulo Mineiro. Foram incluídos 26 pacientes em: Grupo Controle (GC: n=12) e Grupo Intervenção (GI: n=14). O GI realizou TMI por no mínimo 2 semanas. As avaliações foram realizadas no pré e pós-operatório. RESULTADOS: Houve aumento da PImáx (p=0,006), da PEmáx (p=0,005) e do VVM (0,042) no GI, após o TMI realizado no pré-operatório em relação ao GC. Na avaliação do PFE não foi observada aumento após o TMI no GI em relação ao GC (p=0,63). Na alta hospitalar houve queda das variáveis avaliadas em ambos os grupos e no 30°PO ocorreu recuperação em relação aos valores iniciais. Quanto a ocorrência de CPPO não houve diferença significativa entre os grupos. CONCLUSÃO: O TMI realizado em nosso estudo melhorou a força muscular inspiratória, expiratória e a função ventilatória no préoperatório, porém não resultou em melhor evolução no pós-operatório de pacientes submetidos a esofagectomia.

INTRODUCTION: Preoperative inspiratory muscle training (IMT) can prevent postoperative pulmonary complications in patients undergoing esophagectomy. OBJECTIVE: To evaluate the effectiveness of preoperative IMT and its postoperative benefits by assessing maximal inspiratory pressure (MIP), maximal expiratory pressure (MEP), maximal voluntary ventilation (MVV), and peak expiratory flow (PEF). MATERIALS AND METHODS: A randomized clinical trial was conducted by the Digestive Tract Surgery Service, University Hospital of the Federal University of Triângulo Mineiro. Twenty-six patients were included: control group (CG, n=12) and intervention group (IG, n=14). Patients of IG underwent IMT for at least 2 weeks. Assessments were performed before and after surgery. RESULTS: There was an increase of MIP (p=0.006), MEP (p=0.005) and MVV (0.042) in IG after preoperative IMT compared to CG. Evaluation of PEF revealed no increase in IG after IMT compared to CG (p=0.63). A decrease in the variables analyzed was observed in both group at discharge and the variables had returned to baseline values on postoperative day 30. There was no significant difference in the frequency of postoperative pulmonary complications between groups. CONCLUSION: The IMT applied in our study improved preoperative inspiratory and expiratory muscle strength and ventilatory function but did not result in better postoperative evolution of patients undergoing esophagectomy.

Experimental study on the efficiency and safety of the manual hyperinflation maneuver as a secretion clearance technique.

OBJECTIVE: To evaluate, in a lung model simulating a mechanically ventilated patient, the efficiency and safety of the manual hyperinflation (MH) maneuver as a means of removing pulmonary secretions. METHODS: Eight respiratory therapists (RTs) were asked to use a self-inflating manual resuscitator on a lung model to perform MH as if to remove secretions, under two conditions: as routinely applied during their clinical practice; and after receiving verbal instructions based on expert recommendations. In both conditions, three clinical scenarios were simulated: normal lung function, restrictive lung disease, and obstructive lung disease. RESULTS: Before instruction, it was common for an RT to compress the resuscitator bag two times, in rapid succession. Proximal pressure (Pprox) was higher before instruction than after. However, alveolar pressure (Palv) never exceeded 42.5 cmH2O (median, 16.1; interquartile range [IQR], 11.7-24.5), despite Pprox values as high as 96.6 cmH2O (median, 36.7; IQR, 22.9-49.4). The tidal volume (VT) generated was relatively low (median, 640 mL; IQR, 505-735), and peak inspiratory flow (PIF) often exceeded peak expiratory flow (PEF), the median values being 1.37 L/s (IQR, 0.99-1.90) and 1.01 L/s (IQR, 0.55-1.28), respectively. A PIF/PEF ratio < 0.9 (which theoretically favors mucus migration toward the central airways) was achieved in only 16.7% of the maneuvers. CONCLUSIONS: Under the conditions tested, MH produced safe Palv levels despite high Pprox. However, the MH maneuver was often performed in a way that did not favor secretion removal (PIF exceeding PEF), even after instruction. The unfavorable PIF/ PEF ratio was attributable to overly rapid inflations and low VT.

Evaluation of the effectiveness of preoperative outpatient pulmonary preparation in patients undergoing esophageal surgery / Avaliação da efetividade do preparo pulmonar ambulatorial no período pré-operatório de cirurgia do esôfago / Evaluación de la efectividad del preparo pulmonar ambulatorial en el período pre-operatorio de cirugía del esôfago

Abstract Introduction: Preoperative inspiratory muscle training (IMT) can minimize the occurrence of complications after esophagectomy. Objective: To evaluate the effects of preoperative IMT in patients undergoing esophageal surgery by determining respiratory muscle strength (PImax and PEmax), pulmonary function (FEV1, FVC, FEV1/FVC) and functional capacity by the 6-minute walk test (6MWT). Methods: Twenty-two patients were randomized into two groups: a control group (CG; n = 10) and an intervention group (IG; n = 12). Only IG performed IMT for a minimum period of 2 weeks. The assessments were conducted pre- and post-surgery. Results: An increase of PImax was observed in IG, but not in CG, in the second preoperative assessment (p = 0.014). Assessment on postoperative day 1 showed a reduction in maximal respiratory pressures in the two groups, but the reduction was more marked in IG (p < 0.05). Partial recovery of the variables evaluated was observed at discharge in the two groups. These variables had fully returned to initial values on postoperative day 30. The distance walked in the 6MWT was greater in IG, but the difference was not significant (p = 0.166). There was no difference in the frequency of pulmonary complications between groups. Conclusion: Preoperative IMT performed in our study improved inspiratory muscle strength but did not influence the postoperative pulmonary function or functional capacity of patients undergoing esophagectomy.

Resumo Introdução: O treinamento muscular inspiratório (TMI), realizado no pré-operatório, pode minimizar a ocorrência de complicações após esofagectomia. Objetivo: Avaliar os efeitos do TMI realizado no pré-operatório da cirurgia do esôfago através da força muscular respiratória (PImáx e PEmáx), da função pulmonar (VEF1, CFV, VEF1/CVF) e da capacidade funcional através do teste de caminhada de 6 minutos (TC6'). Métodos: 22 pacientes foram randomizados em: Grupo Controle (GC; n = 10) e Grupo Intervenção (GI; n = 12). Somente o GI realizou TMI por no mínimo 2 semanas. As avaliações foram realizadas no pré e pós-operatório. Resultados: Houve aumento da PImáx no GI na 2° PRÉ (p = 0,014), enquanto no GC não houve alteração. Na avaliação do 1°PO os dois grupos apresentaram redução das pressões respiratórias máximas, porém a redução foi mais acentuada no GI (p < 0,05). Na alta hospitalar ocorreu recuperação parcial das variáveis avaliadas em ambos os grupos e no 30°PO ocorreu recuperação plena em relação aos valores iniciais. Em relação ao TC6' houve um aumento da distância percorrida no GI, mas não foi significante (p = 0,166). Não houve diferença na ocorrência de CP entre os grupos. Conclusão: O TMI realizado em nosso estudo melhorou a força muscular inspiratória, mas não influenciou a função pulmonar e a capacidade funcional pós-operatória de pacientes submetidos a esofagectomia.

Resumen Introducción: El entrenamiento muscular inspiratorio (TMI), realizado en el preoperatorio, puede minimizar la ocurrencia de complicaciones después de la esofagectomía. Objetivo: Evaluar los efectos del TMI realizado en el preoperatorio de la cirugía del esófago a través de la fuerza muscular respiratoria (PImáx y PEmáx), de la función pulmonar (VEF1, CFV, VEF1 / CVF) y de la capacidad funcional a través del test de caminata de 6 minutos (TC6'). Métodos: 22 pacientes fueron randomizados en: Grupo Control (GC, n = 10) y Grupo Intervención (GI; n = 12). Sólo el GI realizó TMI por lo menos 2 semanas. Las evaluaciones se realizaron en el pre y postoperatorio. Resultados: Hubo aumento de la PImáx en el GI en el 2°PRÉ (p = 0,014), mientras que en el GC no hubo alteración. En la evaluación del 1°PO los dos grupos presentaron reducción de las presiones respiratorias máximas, pero la reducción fue más acentuada en el GI (p < 0,05). En el alta hospitalaria ocurrió recuperación parcial de las variables evaluadas en ambos grupos y en el 30°PO ocurrió recuperación plena en relación a los valores iniciales. En relación al TC6'hubo un aumento de la distancia recorrida en el GI, pero no fue significativo (p = 0,166). No hubo diferencia en la ocurrencia de CP entre los grupos. Conclusión: El TMI realizado en nuestro estudio mejoró la fuerza muscular inspiratoria, pero no influenció la función pulmonar y la capacidad funcional postoperatoria de pacientes sometidos a esofagectomía.

Evaluation of manual resuscitators used in ICUs in Brazil.

OBJECTIVE: To evaluate the performance of manual resuscitators (MRs) used in Brazil in accordance with international standards. METHODS: Using a respiratory system simulator, four volunteer physiotherapists employed eight MRs (five produced in Brazil and three produced abroad), which were tested for inspiratory and expiratory resistance of the patient valve; functioning of the pressure-limiting valve; and tidal volume (VT) generated when the one-handed and two-handed techniques were used. The tests were performed and analyzed in accordance with the American Society for Testing and Materials (ASTM) F920-93 criteria. RESULTS: Expiratory resistance was greater than 6 cmH2O . L-1 . s-1 in only one MR. The pressure-limiting valve, a feature of five of the MRs, opened at low pressures (< 17 cmH2O), and the maximal pressure was 32.0-55.9 cmH2O. Mean VT varied greatly among the MRs tested. The mean VT values generated with the one-handed technique were lower than the 600 mL recommended by the ASTM. In the situations studied, mean VT was generally lower from the Brazilian-made MRs that had a pressure-limiting valve. CONCLUSIONS: The resistances imposed by the patient valve met the ASTM criteria in all but one of the MRs tested. The pressure-limiting valves of the Brazilian-made MRs usually opened at low pressures, providing lower VT values in the situations studied, especially when the one-handed technique was used, suggesting that both hands should be used and that the pressure-limiting valve should be closed whenever possible.

Influence of forward leaning and incentive spirometry on inspired volumes and inspiratory electromyographic activity during breathing exercises in healthy subjects.

Breathing exercises (BE), incentive spirometry and positioning are considered treatment modalities to achieve lung re-expansion. This study evaluated the influence of incentive spirometry and forward leaning on inspired tidal volumes (V(T)) and electromyographic activity of inspiratory muscles during BE. Four modalities of exercises were investigated: deep breathing, spirometry using both flow and volume-oriented devices, and volume-oriented spirometry after modified verbal instruction. Twelve healthy subjects aged 22.7 ± 2.1 years were studied. Surface electromyography activity of diaphragm, external intercostals, sternocleidomastoid and scalenes was recorded. Comparisons among the three types of exercises, without considering spirometry after modified instruction, showed that electromyographic activity and V(T) were lower during volume-oriented spirometry (p = 0.000, p = 0.054, respectively). Forward leaning resulted in a lower V(T) when compared to upright sitting (p = 0.000), but electromyographic activity was not different (p = 0.606). Inspired V(T) and electromyographic activity were higher during volume-oriented spirometry performed after modified instruction when compared with the flow-oriented device (p = 0.027, p = 0.052, respectively). In conclusion BE using volume-oriented spirometry before modified instruction resulted in a lower work of breathing as a result of a lower V(T) and was not a consequence of the device type used. Forward leaning might not be assumed by healthy subjects during situations of augmented respiratory demand.

Influence of inspiratory muscle training on weaning patients from mechanical ventilation: a systematic review / Influência do treinamento muscular inspiratório no desmame da ventilação mecânica: uma revisão sistemática

Abstract Introduction: The inability of respiratory muscles to generate force and endurance is recognized as an important cause of failure in weaning patients from invasive mechanical ventilation (IMV). Thus, inspiratory muscle training (IMT) might be an interesting treatment option for patients with prolonged IMV weaning. Objective: The aim of this systematic literature review was to evaluate the effectiveness of inspiratory muscle training in weaning patients from mechanical ventilation and to identify the most effective type of training for this particular purpose. Methods: We searched PubMed, LILACS, PEDro and Web of Science for randomized clinical trials published in English or Portuguese from January 1990 until March 2015. Results: Eighty-nine studies were identified of which five were selected. A total of 267 patients participated in the five randomized clinical trials analyzed here. IMV duration before onset of training varied greatly among subjects. Three studies performed IMT using a threshold device and two studies used adjustments of ventilator pressure sensitivity. Four studies have shown that IMT resulted in a significant increase in inspiratory maximal pressure. Only two studies, however, have reported that IMT resulted in higher success rates in weaning patients from IMV. One study has found that patients showed a shorter ventilator weaning duration after IMT. Conclusion: IMT using pressure threshold devices results in increased inspiratory muscle strength and can therefore be considered a more effective treatment option and with the potential to optimize ventilator weaning success in patients at risk of prolonged IMV.

Resumo Introdução: A incapacidade da musculatura respiratória em gerar força e resistência constitui uma importante causa de insucesso no desmame da ventilação mecânica invasiva (VMI). Neste contexto, o treinamento da musculatura inspiratória (TMI) torna-se uma opção de tratamento para pacientes que evoluem com desmame da VMI prolongado. Objetivos: Realizar uma revisão sistemática para avaliar a efetividade do TMI no desmame de pacientes da VMI e identificar a forma de treinamento mais efetivo. Métodos: Foram incluídos apenas ensaios clínicos randomizados, nos idiomas português e/ou inglês, publicados entre janeiro de 1990 e março de 2015. A busca foi realizada nas bases de dados eletrônicas Pubmed, LILACS, PEDro e Web of Science. Resultados: Foram identificados 89 estudos, mas apenas cinco foram selecionados. Participaram dos cinco ensaios randomizados 267 pacientes com tempo de VMI, antes do início do treinamento, diverso. O TMI aplicado foi distinto, dois estudos utilizaram a sensibilidade do ventilador e três estudos, aparelhos com limiar de pressão (threshold). Quatro estudos mostraram que o TMI resultou em aumento da pressão máxima inspiratória. No entanto, apenas dois estudos reportaram que o TMI resultou em maior taxa de sucesso no desmame da VMI e um estudo, em menor tempo de desmame ventilatório. Conclusão: O TMI realizado com aparelhos com limiar de pressão resulta em aumento da força muscular inspiratória e, portanto, pode ser considerado mais efetivo e com potencial para otimizar o desmame de pacientes com risco de VMI prolongada.

Bronchial hygiene technique with manual hyperinflation and thoracic compression: effectiveness and safety. / Efetividade e segurança da técnica de higiene brônquica: hiperinsuflação manual com compressão torácica.

OBJECTIVES: To evaluate the effects of the manual hyperinflation with thoracic compression (MHTC) maneuver on the clearance of secretions, pulmonary mechanics, hemodynamics and oxygenation in mechanically ventilated patients. METHODS: This was a controlled, crossover study that included twenty patients who were under invasive ventilation for more than 48 hours. Four hours after the last airway suctioning procedure, the patients underwent the study interventions, Suction alone or MHTC plus Suction, in sequence at four hour intervals. The sequence order for the procedures was established by randomization. Data were collected before, during and 5, 15, 30 and 60 minutes after each intervention. The suctioned secretions were collected and weighed. RESULTS: No significant differences between the procedures were found regarding tidal volume, plateau pressure and pulmonary compliance (p>0.05). The hemodynamic variables showed increased pressures and heart rate during the procedures and returned to baseline values five minutes after the end of the procedure (p≤0.001). No significant hemodynamic differences were seen between the interventions (p>0.05). For the duration of the study, oxygen saturation was 99% with only two exceptions during the MHTC + Suction procedure, where saturation was 98% (p<0.05). No significant differences were observed between the techniques regarding the weight of the suctioned secretion. CONCLUSION: The results suggest that MHTC, as performed in this study, adds no benefit with respect to oxygenation optimization, pulmonary mechanics and clearance of secretions. However, the MHTC maneuver did not result in hemodynamic changes when compared to the suctioning procedure alone.

Efeitos de um programa de reabilitação pulmonar padrão após um período mínimo de tratamento / Effects of a standard pulmonary rehabilitation program after a minimal period of treatment

A Reabilitação Pulmonar (RP) é considerada essencial no tratamento de pacientes com doença pulmonar obstrutiva crônica (DPOC), sendo o condicionamento físico o seu componente chave. A melhor forma de execução desse componente e o seu período mínimo de duração são alvos de investigação científica. O presente estudo piloto teve como objetivo relatar os efeitos de um programa de RP padrão - caracterizado por englobar exercícios de força e de resistência de musculatura sistêmica e respiratória - após um período mínimo (12 sessões) e longo (cinco meses) de tratamento. Participaram do estudo dez pacientes, com DPOC, estádio III, com idade média de 68,1 ± 9,9 anos, sendo oito pacientes do sexo masculino. O treinamento foi realizado três vezes por semana, com duração de 60-70 minutos por sessão, conforme protocolo constituído por: aquecimento; treinamento da musculatura inspiratória; treinamento aeróbio em bicicleta ergométrica por 30 minutos; treinamento resistido de membros superiores e inferiores; e desaquecimento. A intensidade do treinamento foi ajustada inicialmente em 60% da máxima obtida nos respectivos testes de avaliação de cada exercício. Após um período mínimo de 12 sessões, os pacientes apresentaram melhora significante da pressão inspiratória máxima, da distância percorrida no teste de caminhada de seis minutos e da qualidade de vida (p<0,05). Após cinco meses de intervenção, as variáveis analisadas apresentaram melhor evolução em relação as primeiras 12 sessões, porém sem diferença estatística significante . O programa de RP padrão adotado em nosso estudo mostrou-se efetivo após curto período de intervenção, porém a continuidade do tratamento pareceu otimizar os benefícios alcançados em 12 sessões.

Pulmonary Rehabilitation (PR) is considered essential in the treatment of patients with chronic obstructive pulmonary disease (COPD) and physical training is considered its key component. The best form of executing this component and its minimal duration are targets of scientific investigation. The aim of this current pilot study was to report the effects of a PR standard program - characterized by force and endurance exercises of systemic and respiratory muscles - after a short (12 sessions) and long (five months) period of treatment. Ten patients, with COPD, stage III, 68.1 ± 9.9 years old, eight of them of male gender participated in the study. Training was conducted three times per week, 60-70 minutes per session, according to a protocol consisted of the following components: warm-up; inspiratory muscle training, aerobic training in a cycle ergometer; resistance training of upper and lower limbs; and cold-down. The intensity of training was initially set at 60% of maximal value obtained at each respective exercise evaluation test. After the initial 12 sessions, the patients presented significant increments in the inspiratory maximal pressure, distance walked on the six-minute walk test and quality of life score (p<0,05). After five months of intervention, the patients presented a more expressive increment of these variables, although without statistical significance in relation to the initial 12 sessions. The standard PR program reveled to be effective in a short period of intervention; however the continuity of treatment may optimize the benefits achieved in 12 sessions.