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.

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.

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.