Soporte ventilatorio no invasivo en insuficiencia ventilatoria aguda severa en adolescentes con enfermedad neuromuscular y obesidad: estudio de casos / Non-invasive ventilatory support in severe acute ventilatory failure in adolescents with neuromuscular disease and obesity: study of cases

Noninvasive ventilatory support (NIVS) combined with mechanical cough assist (MI-E) is an effective tool to treat patients with acute ventilatory failure due to neuromuscular disorders (NMD). Airway respiratory infection could be lethal or with risk of endotraqueal intubation, especially when vital capacity (VC) is less than 15 ml/k. We report 2 obese adolescents, aged 11 and 14 years old, with myasthenic crisis (MC) and Duchenne muscular dystrophy (DMD). The last one with a severe cifoescoliosis treated with nocturnal noninvasive ventilation at home. MC girl has been treated with pyridostigmine, prednisolone and mycophenolate. They were admitted for thymectomy and spinal surgery arthrodesis respectively. After admission they developed airway respiratory infection triggering by Methaneumovirus and were treated with oxygen therapy, non-invasive ventilation with low-pressure support and EV immunoglobulin for the MC girl. After 48 h both patients developed severe respiratory failure, Sa/FiO2 < 200, atelectasis of lower lobes and difficulty to swallow, a peak cough flow (PFT)

El soporte ventilatorio no invasivo (SVNI) y la rehabilitación respiratoria con apilamiento de aire más tos asistida manual o mecánica, son efectivas para tratar la insuficiencia ventilatoria aguda en pacientes con enfermedades neuromusculares (ENM) y deterioro progresivo de la bomba respiratoria. Las agudizaciones gatilladas por infecciones respiratorias causan insuficiencia ventilatoria aguda potencialmente mortal y con alto riesgo de intubación, en especial cuando la capacidad vital (CV) es < de 15ml/k. Se reportan 2 adolescentes obesos con ENM de 11 y 14 años con miastenia gravis y distrofia muscular de Duchenne (DMD) con asistencia ventilatoria no invasiva nocturna con baja presión de soporte (AVNI), ingresados para timectomía y artrodesis de columna respectivamente. Una vez ingresados evolucionan con insuficiencia ventilatoria aguda secundaria a una infección respiratoria por Metaneumovirus. Inicialmente fueron manejados con oxigenoterapia, AVNI y gamaglobulina endovenosa en el caso de la paciente con crisis miasténica (CM). A las 48h presentan dificultad respiratoria severa, Sa/FiO2 < 200, atelectasias bibasales y disfagia, CV de 800ml (11ml/k) en el paciente con CM y de 200 ml (2,5ml/k) en el paciente con DMD y un pico flujo tosido (PFT) < 100 l/m. Se cambia a SVNI con equipo Trilogy® y BipapA40®, en modalidad S/T (espontáneo/tiempo) y AVAPS (volumen promedio asegurado en presión de soporte) con altos parámetros ventilatorios; suspendiendo rápidamente la oxigenoterapia, al combinar tos mecánicamente asistida con in-exsufflator (MI-E) en forma intensiva. Ambos pacientes presentan mejoría clínica sostenida, de la CV, PFT y pico flujo exuflado máximo con MI-E (PFE-MI-E). El SVNI más la aplicación sistemática del MI-E hasta lograr SaO2 de al menos 95% con oxígeno ambiental evita la intubación endotraqueal en ENM, a diferencia del agravamiento producido por AVNI y oxigenoterapia con criterios clásicos.

Presiones y pico flujo tosido en la asistencia mecánica de la tos / Pressures used and peak cough flow during mechanical cough assistance

Introducción: En las personas con enfermedad neuromuscular, la incapacidad para toser y para generar flujos espiratorios adecuados constituye el principal limitante para mantener una adecuada salud del sistema respiratorio. La asistencia mecánica de la tos es un dispositivo que genera presión positiva y negativa en la vía aérea y simula una tos normal. Se realizó una revisión bibliográfica. Se incluyeron 9 estudios, con un total de 235 sujetos adultos con enfermedad neuromuscular. Objetivos: Describir los valores de presiones de insuflación y exsuflación utilizados y su relación con los valores de pico flujo tosido. Desarrollo: El 28 por ciento era de género femenino y las edades estaban comprendidas entre 14 a 77 años. Las presiones utilizadas variaron entre los estudios, con valores que iban desde +15/ -15 cm H2O a los +40/ -40 cm H2O. Con respecto a los valores de pico flujo tosido, 7 estudios observaron incrementos estadísticamente significativos al aplicar la terapéutica. En estos estudios, para obtener un flujo espiratorio superior a 160 L/min se requirieron presiones de al menos -30/+30 cm H2O. Conclusiones: Se requieren futuras investigaciones que permitan el desarrollo de un consenso respecto a aplicación de la asistencia mecánica de la tos en sujetos con enfermedad neuromuscular, así como establecer criterios de selección de las presiones de insuflación y exsuflación a programar durante la terapéutica(AU)

Introduction: In people with neuromuscular disease, the inability to cough and generate adequate expiratory flows is the main limitation to maintain adequate health of the respiratory system. The mechanical assistance of the cough is a device that generates positive and negative pressure in the airway, simulating a normal cough. 9 studies were included, with a total of 235 adult subjects with neuromuscular disease. Objectives: Describe the values ​​of insufflation and exsufflation pressures used and to describe their relationship with peak cough flow values. Development: 28 percent were female and the ages between 14 and 77 years old. The pressures used varied between the different studies, with values ​​ranging from + 15 / -15 cm H2O to + 40 / -40 cm H2O. According to the peak cough flow values, seven studies observed statistically significant increases when applying the therapy. In these studies, to obtain an expiratory flow greater than 160 L / min, at least -30 / + 30 cm H2O were required. Conclusions: Future research is required to allow the development of a consensus regarding the application of mechanical cough assistance in subjects with neuromuscular disease, as well as establishing selection criteria for insufflation and exsufflation pressures to be programmed during therapy(AU)

Improvement of Peak Cough Flow After the Application of a Mechanical In-exsufflator in Patients With Neuromuscular Disease and Pneumonia: A Pilot Study.

OBJECTIVE: To investigate and demonstrate persistent increase of peak cough flow after mechanical in-exsufflator application, in patients with neuromuscular diseases and pneumonia. METHODS: A mechanical in-exsufflator was applied with patients in an upright or semi-upright sitting position (pressure setting, +40 and -40 cmH2O; in-exsufflation times, 2-3 and 1-2 seconds, respectively). Patients underwent five cycles, with 20-30 second intervals to prevent hyperventilation. Peak cough flow without and with assistive maneuvers, was evaluated before, and 15 and 45 minutes after mechanical in-exsufflator application. RESULTS: Peak cough flow was 92.6 L/min at baseline, and 100.4 and 100.7 L/min at 15 and 45 minutes after mechanical in-exsufflator application, respectively. Assisted peak cough flow at baseline, 15 minutes, and 45 minutes after mechanical in-exsufflator application was 170.7, 179.3, and 184.1 L/min, respectively. While peak cough flow and assisted peak cough flow increased significantly at 15 minutes after mechanical in-exsufflator application compared with baseline (p=0.030 and p=0.016), no statistical difference was observed between 15 and 45 minutes. CONCLUSION: Increased peak cough flow after mechanical in-exsufflator application persists for at least 45 minutes.

Improvement of Peak Cough Flow After the Application of a Mechanical In-exsufflator in Patients With Neuromuscular Disease and Pneumonia: A Pilot Study

OBJECTIVE: To investigate and demonstrate persistent increase of peak cough flow after mechanical in-exsufflator application, in patients with neuromuscular diseases and pneumonia. METHODS: A mechanical in-exsufflator was applied with patients in an upright or semi-upright sitting position (pressure setting, +40 and −40 cmH2O; in-exsufflation times, 2–3 and 1–2 seconds, respectively). Patients underwent five cycles, with 20–30 second intervals to prevent hyperventilation. Peak cough flow without and with assistive maneuvers, was evaluated before, and 15 and 45 minutes after mechanical in-exsufflator application. RESULTS: Peak cough flow was 92.6 L/min at baseline, and 100.4 and 100.7 L/min at 15 and 45 minutes after mechanical in-exsufflator application, respectively. Assisted peak cough flow at baseline, 15 minutes, and 45 minutes after mechanical in-exsufflator application was 170.7, 179.3, and 184.1 L/min, respectively. While peak cough flow and assisted peak cough flow increased significantly at 15 minutes after mechanical in-exsufflator application compared with baseline (p=0.030 and p=0.016), no statistical difference was observed between 15 and 45 minutes. CONCLUSION: Increased peak cough flow after mechanical in-exsufflator application persists for at least 45 minutes.

Noninvasive airway approaches for acute neuromuscular respiratory failure in emergency departments.

Emerging evidence advocates for noninvasive ventilation (NIV) combined with mechanical in-exsufflation (MIE) as a first-line approach for acute respiratory failure (ARF) in patients with neuromuscular disorders (NMD). To date, most NIV studies of ARF in NMD patients have been performed in intensive care units or in hospital settings. However, the utility of using combined NIV/MIE in the emergency department (ED) settings is unclear. We report on the implementation of NIV/MIE in two children with type II spinal muscular atrophy who presented to the ED with ARF. This is the first report on the feasibility and efficacy of combining NIV/MIE in ED settings for pediatric NMD patients with ARF.

Respiratory Implications of Pediatric Neuromuscular Disease.

Children with progressive neuromuscular weakness undergo a stereotypical progression of respiratory involvement, beginning with impaired airway clearance and progressing to nocturnal and then diurnal ventilatory failure. This review examines issues related to airway clearance and mucus mobilization, sleep problems, and use of assisted ventilation in children with neuromuscular diseases. Interventions for each of these problems have been created or adapted for the pediatric population. The use of airway clearance therapies and assisted ventilation have improved survival of children with neuromuscular weakness. Questions regarding the best time to introduce some therapies, the therapeutic utility of certain interventions, and the cost-effectiveness of various treatments demand further investigation. Studies that assess the potential to improve quality of life and reduce hospitalizations and frequency of lower-respiratory tract infections will help clinicians to decide which techniques are best suited for use in children. As children with neuromuscular disease survive longer, coordinated programs for transitioning these patients to adult care must be developed to enhance their quality of life.

A Comparison of Cough Assistance Techniques in Patients with Respiratory Muscle Weakness.

PURPOSE: To assess the ability of a mechanical in-exsufflator (MI-E), either alone or in combination with manual thrust, to augment cough in patients with neuromuscular disease (NMD) and respiratory muscle dysfunction. MATERIALS AND METHODS: For this randomized crossover single-center controlled trial, patients with noninvasive ventilator-dependent NMD were recruited. The primary outcome was peak cough flow (PCF), which was measured in each patient after a cough that was unassisted, manually assisted following a maximum insufflation capacity (MIC) maneuver, assisted by MI-E, or assisted by manual thrust plus MI-E. The cough augmentation techniques were provided in random order. PCF was measured using a new device, the Cough Aid. RESULTS: All 40 enrolled participants (37 males, three females; average age, 20.9±7.2 years) completed the study. The mean (standard deviation) PCFs in the unassisted, manually assisted following an MIC maneuver, MI-E-assisted, and manual thrust plus MI-E-assisted conditions were 95.7 (40.5), 155.9 (53.1), 177.2 (33.9), and 202.4 (46.6) L/min, respectively. All three interventions significantly improved PCF. However, manual assistance following an MIC maneuver was significantly less effective than MI-E alone. Manual thrust plus MI-E was significantly more effective than both of these interventions. CONCLUSION: In patients with NMD and respiratory muscle dysfunction, MI-E alone was more effective than manual assistance following an MIC maneuver. However, MI-E used in conjunction with manual thrust improved PCF even further.

A Comparison of Cough Assistance Techniques in Patients with Respiratory Muscle Weakness

PURPOSE: To assess the ability of a mechanical in-exsufflator (MI-E), either alone or in combination with manual thrust, to augment cough in patients with neuromuscular disease (NMD) and respiratory muscle dysfunction. MATERIALS AND METHODS: For this randomized crossover single-center controlled trial, patients with noninvasive ventilator-dependent NMD were recruited. The primary outcome was peak cough flow (PCF), which was measured in each patient after a cough that was unassisted, manually assisted following a maximum insufflation capacity (MIC) maneuver, assisted by MI-E, or assisted by manual thrust plus MI-E. The cough augmentation techniques were provided in random order. PCF was measured using a new device, the Cough Aid. RESULTS: All 40 enrolled participants (37 males, three females; average age, 20.9±7.2 years) completed the study. The mean (standard deviation) PCFs in the unassisted, manually assisted following an MIC maneuver, MI-E-assisted, and manual thrust plus MI-E-assisted conditions were 95.7 (40.5), 155.9 (53.1), 177.2 (33.9), and 202.4 (46.6) L/min, respectively. All three interventions significantly improved PCF. However, manual assistance following an MIC maneuver was significantly less effective than MI-E alone. Manual thrust plus MI-E was significantly more effective than both of these interventions. CONCLUSION: In patients with NMD and respiratory muscle dysfunction, MI-E alone was more effective than manual assistance following an MIC maneuver. However, MI-E used in conjunction with manual thrust improved PCF even further.

A Comparison of Cough Assistance Techniques in Patients with Respiratory Muscle Weakness

PURPOSE: To assess the ability of a mechanical in-exsufflator (MI-E), either alone or in combination with manual thrust, to augment cough in patients with neuromuscular disease (NMD) and respiratory muscle dysfunction. MATERIALS AND METHODS: For this randomized crossover single-center controlled trial, patients with noninvasive ventilator-dependent NMD were recruited. The primary outcome was peak cough flow (PCF), which was measured in each patient after a cough that was unassisted, manually assisted following a maximum insufflation capacity (MIC) maneuver, assisted by MI-E, or assisted by manual thrust plus MI-E. The cough augmentation techniques were provided in random order. PCF was measured using a new device, the Cough Aid. RESULTS: All 40 enrolled participants (37 males, three females; average age, 20.9±7.2 years) completed the study. The mean (standard deviation) PCFs in the unassisted, manually assisted following an MIC maneuver, MI-E-assisted, and manual thrust plus MI-E-assisted conditions were 95.7 (40.5), 155.9 (53.1), 177.2 (33.9), and 202.4 (46.6) L/min, respectively. All three interventions significantly improved PCF. However, manual assistance following an MIC maneuver was significantly less effective than MI-E alone. Manual thrust plus MI-E was significantly more effective than both of these interventions. CONCLUSION: In patients with NMD and respiratory muscle dysfunction, MI-E alone was more effective than manual assistance following an MIC maneuver. However, MI-E used in conjunction with manual thrust improved PCF even further.

A preliminary randomized trial of the mechanical insufflator-exsufflator versus breath-stacking technique in patients with amyotrophic lateral sclerosis.

A major problem faced by patients with amyotrophic lateral sclerosis (ALS) in respiratory failure is the inability to cough effectively. Forty eligible ALS patients were randomized to the breath-stacking technique using a lung volume recruitment bag (n = 21) or mechanical insufflator-exsufflator MI-E (n = 19) and followed up at three-monthly intervals for at least 12 months or until death. Results showed that there were 13 episodes of chest infection in the breath-stacking group and 19 episodes in the MI-E group (p = 0.92), requiring 90 and 95 days of antibiotics, respectively (p = 0.34). The mean duration of symptoms per chest infection was 6.9 days in the breath-stacking group and 3.9 days in MI-E group (p = 0.16). There were six episodes of hospitalization in each group (p = 0.64). The chance of hospitalization, in the event of a chest infection, was 0.46 in the breath-stacking group and 0.31 in MI-E group (p = 0.47). Median survival in the breath-stacking group was 535 days and 266 days in the MI-E group (p = 0.34). The QoL was maintained above 75% of baseline for a median of 329 days in the breath-stacking group and 205 days in the MI-E group (p = 0.41). In conclusion, lack of statistically significant differences due to sub-optimal power and confounders precludes a definitive conclusion with respect to the relative efficacy of one cough augmentation technique over the other. This study however, provides useful lessons and informative data, needed to strengthen the power calculation, inclusion criteria and randomization factors for a large scale definitive trial. Until such a definitive trial can be undertaken, we recommend the breath-stacking technique as a low-cost, first-line intervention for volume recruitment and cough augmentation in patients with ALS who meet the criteria for intervention with non-invasive ventilation.

Combined noninvasive ventilation and mechanical in-exsufflator in the treatment of pediatric acute neuromuscular respiratory failure.

OBJECTIVES: The present study aims to evaluate the efficacy and complications of combined noninvasive ventilation (NIV) and assisted coughing by mechanical in-exsufflator (MIE) for acute respiratory failure (ARF) in children with neuromuscular disease (NMD). METHODS: A prospective study was conducted in the pediatric intensive care unit. Children with NMD and ARF treated by combined NIV and MIE were included. Treatment success was defined as freedom from tracheal intubation during the hospital stay. Physiologic indices including PaO2 , PaCO2 , pH, and PaO2 /FiO2 were recorded before and 12, 24 hr after the use of NIV/MIE. RESULTS: Combined NIV/MIE was used in 15 NMD children (mean: 8.1 years, range: 3 months to 18 years) with 16 cases of ARF. There was no mortality in this cohort. Treatment success was achieved in 12 cases (75%), including six cases (38%) demanding "Do Not Intubate." ARF was due to pneumonia, with a mean baseline PaCO2 of 73.2 ± 19.0 mmHg. In the success group, hypercarbia and acidosis improved after use of NIV/MIE for 24 hr (PaCO2 : 71.7 ± 18.6 mmHg vs. 55.8 ± 11.6 mmHg, P < 0.01; pH: 7.29 ± 0.07 vs. 7.38 ± 0.05, P < 0.01). All patients tolerated NIV/MIE well despite transient skin pressure sores in five cases. CONCLUSIONS: Combined NIV/MIE is a safe and effective approach to rapidly improve physiologic indices and decrease the need for intubation in NMD children with ARF. NIV/MIE provides a good alternative for those refusing intubation.

Fatal hepatic hemorrhage by peliosis hepatis in X-linked myotubular myopathy: a case report.

We report a 5-year-old boy with X-linked myotubular myopathy complicated by peliosis hepatis. At birth, he was affected with marked generalized muscle hypotonia and weakness, which required permanent ventilatory support, and was bedridden for life. He died of acute fatal hepatic hemorrhage after using a mechanical in-exsufflator. Peliosis hepatis, defined as multiple, variable-sized, cystic blood-filled spaces through the liver parenchyma, was confirmed by autopsy. To avoid fatal hepatic hemorrhage by peliosis hepatis, routine hepatic function tests and abdominal imaging tests should be performed for patients with X-linked myotubular myopathy, especially at the time of using artificial respiration.

Asistencia mecánica de la tos: dispositivo de tos asistida, in-exsufflator / In-exsufflator assisted cough devices

Este capitulo describe los fundamentos e indicaciones del equipo electromecánico de tos asistida, “in-exsufflator”, en pacientes con enfermedades neuromusculares u otras condiciones que comprometen la eficacia en la remoción de las secreciones traqueobronquiales relacionadas a mecanismos de tos ineficiente. Se señalan los criterios de selección para la entrega de esta terapia kinésica y el funcionamiento básico de este dispositivo. Además se propone un protocolo complementario de manejo kinésico para pacientes neuromusculares usuarios de asistencia ventilatoria no invasiva e invasiva.

The Efficacy of Pulmonary Rehabilitation Using Mechanical In-Exsufflator in Cervical Cord Injured Patients

OBJECTIVE: It is known that Mechanical in-exsufflator (MI-E) can reduce pulmonary complications such as pneumonia, atelectasis in tetraplegia by increasing inspiratory and expiratory capacity. The aim of this study is to clarify the effectiveness of MI-E on pulmonary function and coughing capacity in tetraplegia. METHOD: Thirty tetraplegic patients who had neither history nor radiologic finding of pulmonary disease were divided into two groups; control (n=15) and experimental (n=15) groups. Control group received conventional pulmonary rehabilitation, while experimental group received additional MI-E therapy for one month. The pulmonary function was evaluated by measuring percentage of predicted value of vital capacity (% VC), maximal insufflation capacity (MIC), unassisted peak cough flow (UPCF), volume assisted peak cough flow (VPCF), manual assisted peak cough flow (MPCF), manual and volume assisted peak cough flow (MVPCF). These data of pulmonary function before and after treatment were compared between two groups. RESULTS: 1) There are significant improvement of pulmonary function in both groups (p<0.05) except UPCF in control group before and after treatment. 2) The experimental group showed more improvement in MIC, VPCF, MPCF and MVPCF than control group (p<0.05). Conclusion: MI-E therapy can be used as an effective therapeutic modality for the improvement of pulmonary function in combination with conventional pulmonary rehabilitation.