Associação entre achados eletromiográficos e mortalidade na unidade de terapia intensiva em pacientes com síndrome do desconforto respiratório agudo mecanicamente ventilados sob sedação profunda / Association between electromyographical findings and intensive care unit mortality among mechanically ventilated acute respiratory distress syndrome patients under profound sedation

RESUMO Objetivo: Avaliar se os achados eletromiográficos podem prever a mortalidade na unidade de terapia intensiva em pacientes sépticos sob ventilação mecânica e sedação profunda. Métodos: Conduziu-se estudo prospectivo de coorte, que inscreveu, de forma consecutiva, pacientes com síndrome do desconforto respiratório agudo moderada a grave (pressão parcial de oxigênio/fração inspirada de oxigênio < 200) com idade ≥ 18 anos, dependentes de ventilação mecânica por 7 ou mais dias, e mantidos sob sedação profunda (escala de agitação e sedação de Richmond ≤ -4). Realizaram-se estudos eletromiográficos dos membros inferiores em todos os pacientes entre o sétimo e o décimo dia de ventilação mecânica. Registraram-se os potenciais de ação dos nervos sensitivos nos nervos mediano e sural, bem como os potenciais de ação compostos para os nervos mediano (músculo abdutor curto do polegar) e fibular comum (músculo extensor curto dos dedos). Resultados: Foram inscritos 17 pacientes durante os 7 meses de duração do estudo. Nove pacientes (53%) tinham sinais eletromiográficos de miopatia ou polineuropatia da doença crítica. O risco de óbito durante o tempo de permanência na unidade de terapia intensiva foi mais elevado nos pacientes com sinais eletromiográficos de miopatia ou polineuropatia da doença crítica, em comparação com aqueles sem esses diagnósticos (77,7% versus 12,5%; log-rank p = 0,02). Conclusão: A presença de sinais eletromiográficos de miopatia ou polineuropatia da doença crítica, entre o sétimo e décimo dias de ventilação mecânica, pode se associar com mortalidade na unidade de terapia intensiva em pacientes com síndrome do desconforto respiratório agudo moderada a grave mantidos sob sedação profunda, nos quais não é possível proceder à avaliação clínica da força muscular.

ABSTRACT Objective: To evaluate whether electromyographical findings could predict intensive care unit mortality among mechanically ventilated septic patients under profound sedation. Methods: A prospective cohort study that consecutively enrolled moderate-severe acute respiratory distress syndrome (partial pressure of oxygen/fraction of inspired oxygen < 200) patients who were ≥ 18 years of age, dependent on mechanical ventilation for ≥ 7 days, and under profound sedation (Richmond Agitation Sedation Scale ≤ -4) was conducted. Electromyographic studies of the limbs were performed in all patients between the 7th and the 10th day of mechanical ventilation. Sensory nerve action potentials were recorded from the median and sural nerves. The compound muscle action potentials were recorded from the median (abductor pollicis brevis muscle) and common peroneal (extensor digitorum brevis muscle) nerves. Results: Seventeen patients were enrolled during the seven months of the study. Nine patients (53%) had electromyographic signs of critical illness myopathy or neuropathy. The risk of death during the intensive care unit stay was increased in patients with electromyographical signs of critical illness myopathy or neuropathy in comparison to those without these diagnostics (77.7% versus 12.5%, log-rank p = 0.02). Conclusion: Electromyographical signs of critical illness myopathy or neuropathy between the 7th and the 10th day of mechanical ventilation may be associated with intensive care unit mortality among moderate-severe acute respiratory distress syndrome patients under profound sedation, in whom clinical strength assessment is not possible.

Critical illness polyneuromyopathy in septic patients: Is it possible to diagnose it in a bedside clinical examination?

OBJECTIVE: To determine the sensitivity and specificity of peripheral and respiratory muscle strength tests in diagnosing critical illness polyneuromyopathy (CIPNM), compared with an electrophysiological examination. METHODS: Fifty septic patients who required mechanical ventilation for at least five days, and without a previous history of muscle weakness, were included. Peripheral muscle strength was assessed using the Medical Research Council (MRC) score, handgrip strength by dynamometry, and respiratory muscle strength with maximum respiratory pressures. Diagnosis of CIPNM was either confirmed or rejected by an electrophysiological examination. Receiver operating characteristic curve analysis was performed to determine the cut-off values with the best sensitivity (SN) and specificity (SP) of the studied variables in the presence or absence of CIPNM. RESULTS: Patients with CIPNM were older, more critical (APACHE IV/SAPS 3), had a longer hospitalization, required mechanical ventilation for longer, and had a higher rate of intensive care unit readmission. Cutoff values identified CIPNM patients using MRC scores, dynamometry according to sex, maximal expiratory and inspiratory pressures, as well as being confirmed by the electrophysiological examination, with good sensitivity and specificity: < 40 (SN: 0.893; SP: 0.955); < 7 kg (SN: 1; SP: 0.909) for men, < 4 kg (SN: 0.882; SP: 1) for women; < 34 cmH2O (SN: 0.808; SP: 0.909) and > -40 cmH2O (SN: 0.846; SP: 0.909), respectively. CONCLUSION: The MRC score, dynamometry or maximum respiratory pressures can be used to identify patients with CIPNM at the intensive care bedside assessment. The healthcare professional can choose any of the methods studied to evaluate the patient, based on his experience and the resource available.

Critical illness polyneuromyopathy in septic patients: Is it possible to diagnose it in a bedside clinical examination? / Polineuromiopatia do doente crítico em pacientes sépticos: É possível diagnosticar em um exame clínico à beira do leito?

ABSTRACT Objective: To determine the sensitivity and specificity of peripheral and respiratory muscle strength tests in diagnosing critical illness polyneuromyopathy (CIPNM), compared with an electrophysiological examination. Methods: Fifty septic patients who required mechanical ventilation for at least five days, and without a previous history of muscle weakness, were included. Peripheral muscle strength was assessed using the Medical Research Council (MRC) score, handgrip strength by dynamometry, and respiratory muscle strength with maximum respiratory pressures. Diagnosis of CIPNM was either confirmed or rejected by an electrophysiological examination. Receiver operating characteristic curve analysis was performed to determine the cut-off values with the best sensitivity (SN) and specificity (SP) of the studied variables in the presence or absence of CIPNM. Results: Patients with CIPNM were older, more critical (APACHE IV/SAPS 3), had a longer hospitalization, required mechanical ventilation for longer, and had a higher rate of intensive care unit readmission. Cutoff values identified CIPNM patients using MRC scores, dynamometry according to sex, maximal expiratory and inspiratory pressures, as well as being confirmed by the electrophysiological examination, with good sensitivity and specificity: < 40 (SN: 0.893; SP: 0.955); < 7 kg (SN: 1; SP: 0.909) for men, < 4 kg (SN: 0.882; SP: 1) for women; < 34 cmH2O (SN: 0.808; SP: 0.909) and > −40 cmH2O (SN: 0.846; SP: 0.909), respectively. Conclusion: The MRC score, dynamometry or maximum respiratory pressures can be used to identify patients with CIPNM at the intensive care bedside assessment. The healthcare professional can choose any of the methods studied to evaluate the patient, based on his experience and the resource available.

RESUMO Objetivo: Determinar a sensibilidade (SN) e especificidade (SP) dos testes de força muscular periférica e respiratória no diagnóstico da Polineuromiopatia do Doente Crítico (PNDC) em comparação com o estudo eletrofisiológico. Métodos: Foram incluídos 50 pacientes sépticos, em ventilação mecânica (VM) durante pelo menos cinco dias e sem história prévia de fraqueza muscular. A força muscular foi avaliada utilizando o escore Medical Research Council (MRC), a força de preensão palmar e as pressões respiratórias máximas. O diagnóstico de PNDC foi confirmado ou excluído pelo estudo eletrofisiológico. A análise da curva ROC foi realizada para determinar os valores de corte com a melhor SN e SP. Resultados: Os pacientes com PNDC eram mais velhos, mais graves, tiveram hospitalização mais longa, necessitaram de VM por mais tempo e apresentaram maior taxa de readmissão na Unidade de Terapia Intensiva. Os valores de corte identificaram os pacientes com PNDC usando o MRC, a dinamometria de acordo com o sexo, as pressões expiratórias e inspiratórias máximas, também confirmado pelo estudo eletrofisiológico, com boa sensibilidade e especificidade: < 40 (SN: 0.893; SP: 0.955), < 7 kg (SN: 1; SP: 0,909) para homens, < 4 kg (SN: 0,882; SP: 1) para mulheres, <34 cmH2O (SN: 0,808; SP: 0,909) e > −40 cmH2O (SN: 0,846; SP: 0,909), respectivamente. Conclusão: Tanto o MRC, a dinamometria quanto as pressões respiratórias máximas podem ser usadas para identificar pacientes com PNDC na avaliação à beira do leito, podendo o profissional de saúde escolher qualquer um dos métodos baseado em sua experiência e no recurso disponível.

Association between electromyographical findings and intensive care unit mortality among mechanically ventilated acute respiratory distress syndrome patients under profound sedation. / Associação entre achados eletromiográficos e mortalidade na unidade de terapia intensiva em pacientes com síndrome do desconforto respiratório agudo mecanicamente ventilados sob sedação profunda.

OBJECTIVE: To evaluate whether electromyographical findings could predict intensive care unit mortality among mechanically ventilated septic patients under profound sedation. METHODS: A prospective cohort study that consecutively enrolled moderate-severe acute respiratory distress syndrome (partial pressure of oxygen/fraction of inspired oxygen < 200) patients who were ≥ 18 years of age, dependent on mechanical ventilation for ≥ 7 days, and under profound sedation (Richmond Agitation Sedation Scale ≤ -4) was conducted. Electromyographic studies of the limbs were performed in all patients between the 7th and the 10th day of mechanical ventilation. Sensory nerve action potentials were recorded from the median and sural nerves. The compound muscle action potentials were recorded from the median (abductor pollicis brevis muscle) and common peroneal (extensor digitorum brevis muscle) nerves. RESULTS: Seventeen patients were enrolled during the seven months of the study. Nine patients (53%) had electromyographic signs of critical illness myopathy or neuropathy. The risk of death during the intensive care unit stay was increased in patients with electromyographical signs of critical illness myopathy or neuropathy in comparison to those without these diagnostics (77.7% versus 12.5%, log-rank p = 0.02). CONCLUSION: Electromyographical signs of critical illness myopathy or neuropathy between the 7th and the 10th day of mechanical ventilation may be associated with intensive care unit mortality among moderate-severe acute respiratory distress syndrome patients under profound sedation, in whom clinical strength assessment is not possible.

OBJETIVO: Avaliar se os achados eletromiográficos podem prever a mortalidade na unidade de terapia intensiva em pacientes sépticos sob ventilação mecânica e sedação profunda. MÉTODOS: Conduziu-se estudo prospectivo de coorte, que inscreveu, de forma consecutiva, pacientes com síndrome do desconforto respiratório agudo moderada a grave (pressão parcial de oxigênio/fração inspirada de oxigênio < 200) com idade ≥ 18 anos, dependentes de ventilação mecânica por 7 ou mais dias, e mantidos sob sedação profunda (escala de agitação e sedação de Richmond ≤ -4). Realizaram-se estudos eletromiográficos dos membros inferiores em todos os pacientes entre o sétimo e o décimo dia de ventilação mecânica. Registraram-se os potenciais de ação dos nervos sensitivos nos nervos mediano e sural, bem como os potenciais de ação compostos para os nervos mediano (músculo abdutor curto do polegar) e fibular comum (músculo extensor curto dos dedos). RESULTADOS: Foram inscritos 17 pacientes durante os 7 meses de duração do estudo. Nove pacientes (53%) tinham sinais eletromiográficos de miopatia ou polineuropatia da doença crítica. O risco de óbito durante o tempo de permanência na unidade de terapia intensiva foi mais elevado nos pacientes com sinais eletromiográficos de miopatia ou polineuropatia da doença crítica, em comparação com aqueles sem esses diagnósticos (77,7% versus 12,5%; log-rank p = 0,02). CONCLUSÃO: A presença de sinais eletromiográficos de miopatia ou polineuropatia da doença crítica, entre o sétimo e décimo dias de ventilação mecânica, pode se associar com mortalidade na unidade de terapia intensiva em pacientes com síndrome do desconforto respiratório agudo moderada a grave mantidos sob sedação profunda, nos quais não é possível proceder à avaliação clínica da força muscular.

Corrigendum to "Public versus Private Healthcare Systems following Discharge from the ICU: A Propensity Score-Matched Comparison of Outcomes".

[This corrects the article DOI: 10.1155/2016/6568531.].

Effects of Mechanical Insufflation-Exsufflation on Airway Mucus Clearance Among Mechanically Ventilated ICU Subjects.

BACKGROUND: Few studies have evaluated the effects of mechanical insufflation-exsufflation (MI-E) in subjects on mechanical ventilation. Therefore, this study aimed to evaluate the effectiveness of MI-E on airway mucus clearance among mechanically ventilated ICU subjects. METHODS: A randomized, parallel-group, open-label trial was conducted between June and November 2017 in a single, mixed ICU. Adult ICU subjects receiving mechanical ventilation for > 24 h with stable ventilatory and hemodynamic status were randomized to receive either standard respiratory physiotherapy alone (control group) or respiratory physiotherapy by using an MI-E device (intervention group). The primary outcome was the weight of aspirated airway mucus after study interventions. Secondary outcomes included variation in static lung compliance (ΔCL), airway resistance (ΔRaw), work of breathing (ΔWOB) in relation to the pre-intervention period, and hemodynamic and ventilator complications during the procedures. RESULTS: There were 90 subjects in each group. The mean ± SD weight of the aspirated airway mucus was higher in the intervention group than in the control group (2.42 ± 2.32 g vs 1.35 ± 1.56 g, P < .001). The ΔCL values in the intervention group were higher than those in the control group (1.76 ± 4.90 mL/cm H2O vs -0.57 ± 4.85 mL/cm H2O, P = .001). The ΔRaw and ΔWOB values were similar between the groups. No hemodynamic or ventilatory complications were observed. CONCLUSIONS: Among the general ICU subjects receiving mechanical ventilation, use of an MI-E device during respiratory physiotherapy resulted in a larger amount of airway mucus clearance than respiratory physiotherapy alone. (ClinicalTrials.gov registration NCT03178565.).

Comportamento dos achados de ultrassonografia pulmonar durante tentativa de respiração espontânea / Behavior of lung ultrasound findings during spontaneous breathing trial

RESUMO Objetivo: Investigar potencial associação entre a presença de linhas B e a falha do desmame. Métodos: Foram inscritos 57 pacientes elegíveis para liberação da ventilação. Excluíram-se pacientes com traqueostomia. Realizou-se avaliação ultrassonográfica pulmonar de seis zonas torácicas imediatamente antes e após o final da tentativa de respiração espontânea. Definiu-se a predominância de linhas B como qualquer perfil com padrão B bilateral anterior. Os pacientes foram seguidos por 48 horas após a extubação. Resultados: Foram extubados com sucesso 38 pacientes; 11 tiveram falha da tentativa de respiração espontânea; e 8 necessitaram de reintubação dentro de 48 horas após extubados. No início da tentativa com peça T, já se observava padrão B ou consolidação nas regiões posterior e inferior dos pulmões em mais de metade dos indivíduos, que permaneceram não aeradas ao final da tentativa. Observou-se certa tendência à perda da aeração pulmonar durante a tentativa de respiração espontânea apenas no grupo com falha da tentativa de respiração espontânea (p = 0,07), assim como maior predominância de padrão B ao final da tentativa (p = 0,01). Conclusão: A perda de aeração pulmonar durante a tentativa de respiração espontânea em áreas pulmonares não dependentes foi demonstrada em pacientes que tiveram falha do desmame.

ABSTRACT Objective: We aimed to investigate a potential association between B-lines and weaning failure. Methods: Fifty-seven subjects eligible for ventilation liberation were enrolled. Patients with tracheostomy were excluded. Lung ultrasound assessments of six thoracic zones were performed immediately before and at the exnd of the spontaneous breathing trial. B-predominance was defined as any profile with anterior bilateral B-pattern. Patients were followed up to 48 hours after extubation. Results: Thirty-eight individuals were successfully extubated; 11 failed the spontaneous breathing trial and 8 needed reintubation within 48 hours of extubation. At the beginning of the T-piece trial, B-pattern or consolidation was already found at the lower and posterior lung regions in more than half of the individuals and remained non-aerated at the end of the trial. A trend toward loss of lung aeration during spontaneous breathing trials was observed only in the spontaneous breathing trial-failure group (p = 0.07), and there was higher B-predominance at the end of the trial (p = 0.01). Conclusion: A loss of lung aeration during the spontaneous breathing trial in non-dependent lung zones was demonstrated in subjects who failed to wean.

Behavior of lung ultrasound findings during spontaneous breathing trial. / Comportamento dos achados de ultrassonografia pulmonar durante tentativa de respiração espontânea.

OBJECTIVE: We aimed to investigate a potential association between B-lines and weaning failure. METHODS: Fifty-seven subjects eligible for ventilation liberation were enrolled. Patients with tracheostomy were excluded. Lung ultrasound assessments of six thoracic zones were performed immediately before and at the exnd of the spontaneous breathing trial. B-predominance was defined as any profile with anterior bilateral B-pattern. Patients were followed up to 48 hours after extubation. RESULTS: Thirty-eight individuals were successfully extubated; 11 failed the spontaneous breathing trial and 8 needed reintubation within 48 hours of extubation. At the beginning of the T-piece trial, B-pattern or consolidation was already found at the lower and posterior lung regions in more than half of the individuals and remained non-aerated at the end of the trial. A trend toward loss of lung aeration during spontaneous breathing trials was observed only in the spontaneous breathing trial-failure group (p = 0.07), and there was higher B-predominance at the end of the trial (p = 0.01). CONCLUSION: A loss of lung aeration during the spontaneous breathing trial in non-dependent lung zones was demonstrated in subjects who failed to wean.

OBJETIVO: Investigar potencial associação entre a presença de linhas B e a falha do desmame. MÉTODOS: Foram inscritos 57 pacientes elegíveis para liberação da ventilação. Excluíram-se pacientes com traqueostomia. Realizou-se avaliação ultrassonográfica pulmonar de seis zonas torácicas imediatamente antes e após o final da tentativa de respiração espontânea. Definiu-se a predominância de linhas B como qualquer perfil com padrão B bilateral anterior. Os pacientes foram seguidos por 48 horas após a extubação. RESULTADOS: Foram extubados com sucesso 38 pacientes; 11 tiveram falha da tentativa de respiração espontânea; e 8 necessitaram de reintubação dentro de 48 horas após extubados. No início da tentativa com peça T, já se observava padrão B ou consolidação nas regiões posterior e inferior dos pulmões em mais de metade dos indivíduos, que permaneceram não aeradas ao final da tentativa. Observou-se certa tendência à perda da aeração pulmonar durante a tentativa de respiração espontânea apenas no grupo com falha da tentativa de respiração espontânea (p = 0,07), assim como maior predominância de padrão B ao final da tentativa (p = 0,01). CONCLUSÃO: A perda de aeração pulmonar durante a tentativa de respiração espontânea em áreas pulmonares não dependentes foi demonstrada em pacientes que tiveram falha do desmame.

Mechanical ventilation weaning protocol improves medical adherence and results.

INTRODUCTION: Implementation of a weaning protocol is related to better patient prognosis. However, new approaches may take several years to become the standard of care in daily practice. We conducted a prospective cohort study to investigate the effectiveness of a multifaceted strategy to implement a protocol to wean patients from mechanical ventilation (MV) and to evaluate the weaning success rate as well as practitioner adherence to the protocol. METHODS: We investigated all consecutive MV-dependent subjects admitted to a medical-surgical intensive care unit (ICU) for >24h over 7years. The multifaceted strategy consisted of continuing education of attending physicians and ICU staff and regular feedback regarding patient outcomes. The study was conducted in three phases: protocol development, protocol and multifaceted strategy implementation, and protocol monitoring. Data regarding weaning outcomes and physician adherence to the weaning protocol were collected during all phases. RESULTS: We enrolled 2469 subjects over 7years, with 1,943 subjects (78.7%) experiencing weaning success. Physician adherence to the protocol increased during the years of protocol and multifaceted strategy implementation (from 38% to 86%, p<0.01) and decreased in the protocol monitoring phase (from 73.9% to 50.0%, p<0.01). However, during the study years, the weaning success of all subjects increased (from 73.1% to 85.4%, p<0.001). When the weaning protocol was evaluated step-by-step, we found high adherence for noninvasive ventilation use (95%) and weaning predictor measurement (91%) and lower adherence for control of fluid balance (57%) and daily interruption of sedation (24%). Weaning success was higher in patients who had undergone the weaning protocol compared to those who had undergone weaning based in clinical practice (85.6% vs. 67.7%, p<0.001). CONCLUSIONS: A multifaceted strategy consisting of continuing education and regular feedback can increase physician adherence to a weaning protocol for mechanical ventilation.

Spontaneous Breathing Trials With T-Piece or Pressure Support Ventilation.

Spontaneous breathing trials (SBTs) are among the most commonly employed techniques to facilitate weaning from mechanical ventilation. The preferred SBT technique, however, is still unclear. To clarify the preferable SBT (T-piece or pressure support ventilation [PSV]), we conducted this systematic review. We then searched the MEDLINE, EMBASE, SciELO, Google Scholar, CINAHL, ClinicalTrials.gov, and Cochrane CENTRAL databases through June 2015, without language restrictions. We included randomized controlled trials involving adult subjects being weaned from mechanical ventilation comparing T-piece with PSV and reporting (1) weaning failure, (2) re-intubation rate, (3) ICU mortality, or (4) weaning duration. Anticipating clinical heterogeneity among the included studies, we compared prespecified subgroups: (1) simple, difficult, or prolonged weaning and (2) subjects with COPD. We summarized the quality of evidence for intervention effects using the GRADE (Grading of Recommendations Assessment, Development, and Evaluation) methodology. We identified 3,674 potentially relevant studies and reviewed 23 papers in full. Twelve studies (2,161 subjects) met our inclusion criteria. Overall, the evidence was of very low to low quality. SBT technique did not influence weaning success (risk ratio 1.23 [0.94-1.61]), ICU mortality (risk ratio 1.11 [0.80-1.54]), or re-intubation rate (risk ratio 1.21 [0.90-1.63]). Prespecified subgroup analysis suggested that PSV might be superior to T-piece with regard to weaning success for simple-to-wean subjects (risk ratio 1.44 [1.11-1.86]). For the prolonged-weaning subgroup, however, T-piece was associated with a shorter weaning duration (weighted mean difference -3.08 [-5.24 to -0.92] d). In conclusion, low-quality evidence is available concerning this topic. PSV may be associated with lower weaning failure rates in the simple-to-wean subgroup. In contrast, in prolonged-weaning subjects, T-piece may be related to a shorter weaning duration, although this is at high risk of bias. Further study of the difficult-to-wean and COPD subgroups is required.

Public versus Private Healthcare Systems following Discharge from the ICU: A Propensity Score-Matched Comparison of Outcomes.

Purpose. The long-term outcomes of patients after discharge from tertiary ICUs as they relate to the public versus private healthcare systems in Brazil have not yet been evaluated. Materials and Methods. A multicenter prospective cohort study was conducted to compare the all-cause mortality and the physical functional status (PFS) 24 months after discharge from the ICU between adult patients treated in the public and private healthcare systems. A propensity score- (PS-) matched comparison of all causes of mortality and PFS 24 months after discharge from the ICU was performed. Results. In total, 928 patients were discharged from the ICU including 172 (18.6%) patients in the public and 756 (81.4%) patients in the private healthcare system. The results of the PS-matched comparison of all-cause mortality revealed higher mortality rates among the patients of the public healthcare system compared to those of the private healthcare system (47.3% versus 27.6%, P = 0.003). The comparison of the PS-matched Karnofsky performance and Lawton activities of daily living scores between the ICU survivors of the public and private healthcare systems revealed no significant differences. Conclusions. The patients of private healthcare system exhibited significantly greater survival rates than the patients of the public healthcare system with similar PFS following ICU discharge.

Inhalation therapy in mechanical ventilation.

Patients with obstructive lung disease often require ventilatory support via invasive or noninvasive mechanical ventilation, depending on the severity of the exacerbation. The use of inhaled bronchodilators can significantly reduce airway resistance, contributing to the improvement of respiratory mechanics and patient-ventilator synchrony. Although various studies have been published on this topic, little is known about the effectiveness of the bronchodilators routinely prescribed for patients on mechanical ventilation or about the deposition of those drugs throughout the lungs. The inhaled bronchodilators most commonly used in ICUs are beta adrenergic agonists and anticholinergics. Various factors might influence the effect of bronchodilators, including ventilation mode, position of the spacer in the circuit, tube size, formulation, drug dose, severity of the disease, and patient-ventilator synchrony. Knowledge of the pharmacological properties of bronchodilators and the appropriate techniques for their administration is fundamental to optimizing the treatment of these patients.

Inhalation therapy in mechanical ventilation / Terapia inalatória em ventilação mecânica

Patients with obstructive lung disease often require ventilatory support via invasive or noninvasive mechanical ventilation, depending on the severity of the exacerbation. The use of inhaled bronchodilators can significantly reduce airway resistance, contributing to the improvement of respiratory mechanics and patient-ventilator synchrony. Although various studies have been published on this topic, little is known about the effectiveness of the bronchodilators routinely prescribed for patients on mechanical ventilation or about the deposition of those drugs throughout the lungs. The inhaled bronchodilators most commonly used in ICUs are beta adrenergic agonists and anticholinergics. Various factors might influence the effect of bronchodilators, including ventilation mode, position of the spacer in the circuit, tube size, formulation, drug dose, severity of the disease, and patient-ventilator synchrony. Knowledge of the pharmacological properties of bronchodilators and the appropriate techniques for their administration is fundamental to optimizing the treatment of these patients.

Pacientes com doenças pulmonares obstrutivas frequentemente necessitam de suporte ventilatório através de ventilação mecânica invasiva ou não invasiva, dependendo da gravidade da exacerbação. O uso de broncodilatadores inalatórios pode reduzir significativamente a resistência das vias aéreas, contribuindo para a melhora da mecânica respiratória e da sincronia do paciente com o respirador. Apesar dos diversos estudos publicados, pouco se conhece sobre a eficácia dos broncodilatadores rotineiramente prescritos para pacientes em ventilação mecânica ou sobre sua distribuição pulmonar. Os agonistas beta-adrenérgicos e as drogas anticolinérgicas são os broncodilatadores inalatórios mais usados em UTIs. Muitos fatores podem influenciar no efeito das drogas broncodilatadoras, entre eles o modo ventilatório, a posição do espaçador no circuito, o tamanho do tubo, a formulação/dose da droga, a gravidade da doença e a sincronia do paciente. O conhecimento das propriedades farmacológicas das drogas broncodilatadoras e das técnicas adequadas para sua administração são fundamentais para otimizar o tratamento desses pacientes.

Changes in respiratory mechanics during respiratory physiotherapy in mechanically ventilated patients.

OBJECTIVE: To evaluate the changes in ventilatory mechanics and hemodynamics that occur in patients dependent on mechanical ventilation who are subjected to a standard respiratory therapy protocol. METHODS: This experimental and prospective study was performed in two intensive care units, in which patients dependent on mechanical ventilation for more than 48 hours were consecutively enrolled and subjected to an established respiratory physiotherapy protocol. Ventilatory variables (dynamic lung compliance, respiratory system resistance, tidal volume, peak inspiratory pressure, respiratory rate, and oxygen saturation) and hemodynamic variables (heart rate) were measured one hour before (T-1), immediately after (T0) and one hour after (T+1) applying the respiratory physiotherapy protocol. RESULTS: During the period of data collection, 104 patients were included in the study. Regarding the ventilatory variables, an increase in dynamic lung compliance (T-1 = 52.3 ± 16.1mL/cmH2O versus T0 = 65.1 ± 19.1mL/cmH2O; p < 0.001), tidal volume (T-1 = 550 ± 134mL versus T0 = 698 ± 155mL; p < 0.001), and peripheral oxygen saturation (T-1 = 96.5 ± 2.29% versus T0 = 98.2 ± 1.62%; p < 0.001) were observed, in addition to a reduction of respiratory system resistance (T-1 = 14.2 ± 4.63cmH2O/L/s versus T0 = 11.0 ± 3.43cmH2O/L/s; p < 0.001), after applying the respiratory physiotherapy protocol. All changes were present in the assessment performed one hour (T+1) after the application of the respiratory physiotherapy protocol. Regarding the hemodynamic variables, an immediate increase in the heart rate after application of the protocol was observed, but that increase was not maintained (T-1 = 88.9 ± 18.7 bpm versus T0 = 93.7 ± 19.2bpm versus T+1 = 88.5 ± 17.1bpm; p < 0.001). CONCLUSION: Respiratory therapy leads to immediate changes in the lung mechanics and hemodynamics of mechanical ventilation-dependent patients, and ventilatory changes are likely to remain for at least one hour.

Alterações da mecânica ventilatória durante a fisioterapia respiratória em pacientes ventilados mecanicamente / Changes in respiratory mechanics during respiratory physiotherapy in mechanically ventilated patients

RESUMO Objetivo: Avaliar as alterações da mecânica ventilatória e da hemodinâmica que ocorrem em pacientes dependentes de ventilação mecânica submetidos a um protocolo padrão de fisioterapia respiratória. Métodos: Estudo experimental e prospectivo realizado em duas unidades de tratamento intensivo, nas quais pacientes dependentes de ventilação mecânica por mais de 48 horas foram alocados, de forma consecutiva, e submetidos a um protocolo estabelecido de manobras de fisioterapia respiratória. Variáveis ventilatórias (complacência pulmonar dinâmica, resistência do sistema respiratório, volume corrente, pressão de pico inspiratório, frequência respiratória e saturação periférica de oxigênio) e hemodinâmicas (frequência cardíaca) foram mensuradas 1 hora antes (T-1), imediatamente (T0) e após 1 hora (T+1) da realização do protocolo de manobras de fisioterapia respiratória. Resultados: Durante o período de coleta dos dados, 104 pacientes foram incluídos no estudo. Quanto às variáveis ventilatórias, houve aumento da complacência pulmonar dinâmica (T-1 = 52,3 ± 16,1mL/cmH2O versus T0 = 65,1 ± 19,1mL/cmH2O; p < 0,001), do volume corrente (T-1 = 550 ± 134mL versus T0 = 698 ± 155mL; p < 0,001) e da saturação periférica de oxigênio (T-1 = 96,5 ± 2,29% versus T0 = 98,2 ± 1,62%; p < 0,001), além de redução da resistência do sistema respiratório (T-1 = 14,2 ± 4,63cmH2O/L/s versus T0 = 11,0 ± 3,43cmH2O/L/s; p < 0,001) logo após a realização das manobras de fisioterapia respiratória. Todas as alterações se mantiveram na avaliação realizada 1 hora (T+1) após as manobras de fisioterapia respiratória. Já com relação às variáveis hemodinâmicas, houve elevação imediata, porém não sustentada da frequência cardíaca (T-1 = 88,9 ± 18,7bpm versus T0 = 93,7 ± 19,2bpm versus T+1 = 88,5 ± 17,1bpm; p < 0,001). Conclusão: Manobras de fisioterapia respiratória geram mudanças imediatas na mecânica pulmonar e na hemodinâmica dos pacientes dependentes da ...

ABSTRACT Objective: To evaluate the changes in ventilatory mechanics and hemodynamics that occur in patients dependent on mechanical ventilation who are subjected to a standard respiratory therapy protocol. Methods: This experimental and prospective study was performed in two intensive care units, in which patients dependent on mechanical ventilation for more than 48 hours were consecutively enrolled and subjected to an established respiratory physiotherapy protocol. Ventilatory variables (dynamic lung compliance, respiratory system resistance, tidal volume, peak inspiratory pressure, respiratory rate, and oxygen saturation) and hemodynamic variables (heart rate) were measured one hour before (T-1), immediately after (T0) and one hour after (T+1) applying the respiratory physiotherapy protocol. Results: During the period of data collection, 104 patients were included in the study. Regarding the ventilatory variables, an increase in dynamic lung compliance (T-1 = 52.3 ± 16.1mL/cmH2O versus T0 = 65.1 ± 19.1mL/cmH2O; p < 0.001), tidal volume (T-1 = 550 ± 134mL versus T0 = 698 ± 155mL; p < 0.001), and peripheral oxygen saturation (T-1 = 96.5 ± 2.29% versus T0 = 98.2 ± 1.62%; p < 0.001) were observed, in addition to a reduction of respiratory system resistance (T-1 = 14.2 ± 4.63cmH2O/L/s versus T0 = 11.0 ± 3.43cmH2O/L/s; p < 0.001), after applying the respiratory physiotherapy protocol. All changes were present in the assessment performed one hour (T+1) after the application of the respiratory physiotherapy protocol. Regarding the hemodynamic variables, an immediate increase in the heart rate after application of the protocol was observed, but that increase was not maintained (T-1 = 88.9 ± 18.7 bpm versus T0 = 93.7 ± 19.2bpm versus T+1 = 88.5 ± 17.1bpm; p < 0.001). Conclusion: Respiratory therapy leads to immediate changes in the lung mechanics and hemodynamics of mechanical ventilation-dependent patients, and ventilatory changes ...

The reality of patients requiring prolonged mechanical ventilation: a multicenter study.

OBJECTIVE: The number of patients who require prolonged mechanical ventilation increased during the last decade, which generated a large population of chronically ill patients. This study established the incidence of prolonged mechanical ventilation in four intensive care units and reported different characteristics, hospital outcomes, and the impact of costs and services of prolonged mechanical ventilation patients (mechanical ventilation dependency ≥ 21 days) compared with non-prolonged mechanical ventilation patients (mechanical ventilation dependency < 21 days). METHODS: This study was a multicenter cohort study of all patients who were admitted to four intensive care units. The main outcome measures were length of stay in the intensive care unit, hospital, complications during intensive care unit stay, and intensive care unit and hospital mortality. RESULTS: There were 5,287 admissions to the intensive care units during study period. Some of these patients (41.5%) needed ventilatory support (n = 2,197), and 218 of the patients met criteria for prolonged mechanical ventilation (9.9%). Some complications developed during intensive care unit stay, such as muscle weakness, pressure ulcers, bacterial nosocomial sepsis, candidemia, pulmonary embolism, and hyperactive delirium, were associated with a significantly higher risk of prolonged mechanical ventilation. Prolonged mechanical ventilation patients had a significant increase in intensive care unit mortality (absolute difference = 14.2%, p < 0.001) and hospital mortality (absolute difference = 19.1%, p < 0.001). The prolonged mechanical ventilation group spent more days in the hospital after intensive care unit discharge (26.9 ± 29.3 versus 10.3 ± 20.4 days, p < 0.001) with higher costs. CONCLUSION: The classification of chronically critically ill patients according to the definition of prolonged mechanical ventilation adopted by our study (mechanical ventilation dependency ≥ 21 days) identified patients with a high risk for complications during intensive care unit stay, longer intensive care unit and hospital stays, high death rates, and higher costs.

48-Hour Fluid Balance Does Not Predict a Successful Spontaneous Breathing Trial.

BACKGROUND: Both premature and delayed liberation from mechanical ventilation are associated with increased morbidity and mortality, and fluid balance could negatively influence extubation outcomes. We sought to determine the impact of fluid balance in the 48 h before a spontaneous breathing trial (SBT) on weaning outcomes in a mixed ICU population. METHODS: This was a prospective observational study in 2 adult medical-surgical ICUs. All enrolled subjects met eligibility criteria for weaning from mechanical ventilation. SBT failure was defined as inability to tolerate a T-piece trial for 30-120 min. Data on demographics, physiology, fluid balance in the 48 h preceding SBT (fluid input minus output over the 48-h period), lung ultrasound findings, and outcomes were collected. RESULTS: Of a total of 250 SBTs, SBT failure eventuated in 51 (20.4%). Twenty-nine subjects (11.6%) had COPD, and 40 subjects (16%) were intubated due to respiratory sepsis. One-hundred eighty-nine subjects (75.6%) were extubated on the first attempt. Compared with subjects with SBT success, SBT failure subjects were younger (median of 66 vs. 75 y, P = .001) and had a higher duration of mechanical ventilation (median of 7 vs. 4 d, P < .001) and a higher prevalence of COPD (19.6 vs. 9.5%, P = .04). There were no statistically significant differences in 48-h fluid balance before SBT between groups (SBT failure, 1,201.65 ± 2,801.68 mL; SBT success, 1,324.39 ± 2,915.95 mL). However, in the COPD subgroup, we found a significant association between positive fluid balance in the 48 h before SBT and SBT failure (odds ratio of 1.77 [1.24-2.53], P = .04). CONCLUSIONS: Fluid balance should not delay SBT indication because it does not predict greater probability of SBT failure in the medical-surgical critically ill population. Notwithstanding, avoiding positive fluid balance in patients with COPD might improve weaning outcomes. (ClinicalTrials.gov registration NCT02022839.).

A realidade dos pacientes que necessitam de ventilação mecânica prolongada: um estudo multicêntrico / The reality of patients requiring prolonged mechanical ventilation: a multicenter study

Objetivo: Na última década ocorreu um aumento no número de pacientes que necessitam manutenção de ventilação mecânica prolongada, resultando no surgimento de uma grande população de pacientes crônicos criticamente enfermos. Este estudo estabeleceu a incidência de ventilação mecânica prolongada em quatro unidades de terapia intensiva e relatou as diferentes características, desfechos hospitalares e impacto nos custos e serviços de pacientes com ventilação mecânica prolongada (dependência de ventilação mecânica por 21 dias ou mais) em comparação a pacientes sem ventilação mecânica prolongada (dependência de ventilação mecânica inferior a 21 dias). Métodos: Este foi um estudo multicêntrico de coorte que envolveu todos os pacientes admitidos em quatro unidades de terapia intensiva. As principais avaliações de desfechos incluíram o tempo de permanência na unidade de terapia intensiva e no hospital, a incidência de complicações durante a permanência na unidade de terapia intensiva, e a mortalidade na unidade de terapia intensiva e no hospital. Resultados: Durante o período do estudo, ocorreram 5.287 admissões às unidades de terapia intensiva. Alguns desses pacientes (41,5%) necessitaram de suporte ventilatório (n = 2.197), e 218 dos pacientes (9,9%) cumpriram os critérios de ventilação mecânica prolongada. Algumas complicações se desenvolveram durante a permanência na unidade de terapia intensiva como fraqueza muscular, úlceras de pressão, sepse nosocomial bacteriana, candidemia, embolia pulmonar, e delirium hiperativo; estas se associaram com um risco significantemente maior de ventilação mecânica prolongada. Os pacientes de ventilação mecânica prolongada tiveram um aumento significante da mortalidade na unidade de terapia intensiva (diferença absoluta = 14,2%; p < 0,001) e da mortalidade hospitalar (diferença absoluta = 19,1%; p < 0,001). O grupo com ventilação mecânica prolongada permaneceu mais dias no hospital após receber alta ...

Objective: The number of patients who require prolonged mechanical ventilation increased during the last decade, which generated a large population of chronically ill patients. This study established the incidence of prolonged mechanical ventilation in four intensive care units and reported different characteristics, hospital outcomes, and the impact of costs and services of prolonged mechanical ventilation patients (mechanical ventilation dependency ≥ 21 days) compared with non-prolonged mechanical ventilation patients (mechanical ventilation dependency < 21 days). Methods: This study was a multicenter cohort study of all patients who were admitted to four intensive care units. The main outcome measures were length of stay in the intensive care unit, hospital, complications during intensive care unit stay, and intensive care unit and hospital mortality. Results: There were 5,287 admissions to the intensive care units during study period. Some of these patients (41.5%) needed ventilatory support (n = 2,197), and 218 of the patients met criteria for prolonged mechanical ventilation (9.9%). Some complications developed during intensive care unit stay, such as muscle weakness, pressure ulcers, bacterial nosocomial sepsis, candidemia, pulmonary embolism, and hyperactive delirium, were associated with a significantly higher risk of prolonged mechanical ventilation. Prolonged mechanical ventilation patients had a significant increase in intensive care unit mortality (absolute difference = 14.2%, p < 0.001) and hospital mortality (absolute difference = 19.1%, p < 0.001). The prolonged mechanical ventilation group spent more days in the hospital after intensive care unit discharge (26.9 ± 29.3 versus 10.3 ± 20.4 days, p < 0.001) with higher costs. Conclusion: The classification of chronically critically ill patients according to the definition of prolonged mechanical ventilation adopted by our study (mechanical ventilation ...

Influence of FIO2 on PaCO2 during noninvasive ventilation in patients with COPD.

BACKGROUND: The administration of a high FIO2 to COPD patients breathing spontaneously may result in hypercapnia, due to reversal of preexisting regional hypoxic pulmonary vasoconstriction, resulting in a greater dead space. Arterial blood gas trends have not been reported in these patients. In a 31-bed medical ICU in a teaching hospital we prospectively investigated the response of 17 CO2-retaining COPD patients, after acute respiratory crisis stabilization with noninvasive ventilation, to an FIO2 of 1.0 for 40 min, after having been noninvasively ventilated with an FIO2 of ≤ 0.50 for 40 min. RESULTS: The mean ± SD baseline findings were: PaO2 101.4 ± 21.7 mm Hg, PaCO2 52.6 ± 10.4 mm Hg, breathing frequency 17.8 ± 3.7 breaths/min, tidal volume 601 ± 8 mL, and Glasgow coma score of 14.8 ± 0.3. PaO2 significantly increased (P < .001) when FIO2 was increased to 1.0, but there was no significant change in PaCO2, breathing frequency, tidal volume, or Glasgow coma score. CONCLUSIONS: During noninvasive ventilation with an FIO2 sufficient to maintain a normal PaO2, a further increase in FIO2 did not increase PaCO2 in our CO2-retaining COPD patients.