Spinal Muscular Atrophy (SMA) Mortality Despite Novel Medications: Case Reports.

ABSTRACT: Despite new effective medications, patients with SMA types 1-3 can continue to have inadequate cough flows to prevent episodes of acute respiratory failure. Ventilator unweanable intubated patients are thought to require tracheostomy tubes. As a result, potentially beneficial medications may be discontinued and patients die despite receiving these medications. Three cases are presented of medically treated, physically strengthening children, with SMA type 1. All three subsequently died or underwent tracheotomy. However, there is no evidence of extubation attempts to noninvasive ventilatory support settings or optimal mechanical insufflation-exsufflation despite this option being described to be over 98% successful for extubating unweanable medically untreated children with SMA1.

Spinal Muscular Atrophy Type 1 Survival Without New Pharmacotherapies: Two Treatment Paradigms.

OBJECTIVES: The aims of the study are to present noninvasive respiratory management outcomes using continuous noninvasive ventilatory support and mechanical in-exsufflation from infancy for spinal muscular atrophy type 1 and to consider bearing on new medical therapies. DESIGN: Noninvasive ventilatory support was begun for consecutively referred symptomatic infants with spinal muscular atrophy type 1 from 1 to 10 mos of age. Intercurrent episodes of respiratory failure were managed by intubation then extubation to continuous noninvasive ventilatory support and mechanical in-exsufflation despite failing ventilator weaning and extubation attempts. Intubations, tracheotomies, and survival were monitored. RESULTS: Of 153 patients with spinal muscular atrophy 1 consecutively referred since 1995, 37 became continuous noninvasive ventilatory support dependent, almost half before 10 yrs of age. Of the 37, 18 required continuous noninvasive ventilatory support for a mean 18.6 ± 3.3 yrs to a mean 25.3 (range, 18-30) yrs of age, dependent from as young as 4 mos of age with 0 to 40 ml of vital capacity. One of the 18 died from COVID-19 acute respiratory distress syndrome at age 24 after 23 yrs of continuous noninvasive ventilatory support. Extubation success rate of 85% per attempt (150/176) resulted in only one undergoing tracheotomy. CONCLUSIONS: Medical treatments begun during the first 6 wks of age convert spinal muscular atrophy 1 into spinal muscular atrophy 2 or 3 but cough flows remain inadequate to avoid many pneumonias that, once resolved by a treatment paradigm of extubation to continuous noninvasive ventilatory support and mechanical in-exsufflation, eliminates need to resort to tracheotomies.

Mechanical Insufflation-Exsufflation Implementation and Management, Aided by Graphics Analysis.

Mechanical insufflation-exsufflation (MIE) facilitates airway clearance to mitigate respiratory infection, decompensation, and ultimately the need for intubation and placement of a tracheostomy tube. Despite widespread adoption as a respiratory support intervention for motor neuron disease, muscular dystrophy, spinal cord injury, and other diseases associated with ventilatory pump failure and ineffective cough peak flow, there is debate in the clinical community about how to optimize settings when MIE is implemented. This article will demonstrate the clinical utility of MIE graphics in titrating the initial MIE settings, guiding upper airway and lung protective strategies and providing insight to clinicians for ongoing clinical management.

Intermittent abdominal pressure ventilation management in neuromuscular diseases: a Delphi panel Consensus.

BACKGROUND: Intermittent abdominal pressure ventilator (IAPV) use started in the 1930s for ventilatory assistance with muscular dystrophy patients. Later, the device was perfected and expanded for other neuromuscular disorders (NMD). In recent years, the morbidity and mortality tracheotomies and trach tubes related renewed the interest around IAPV. However, there are no guidelines for its use. This study aimed to establish a consensus among physicians involved in its practice to provide IAPV suggestions for the treatment of patients with NMD. METHOD: A 3-step modified Delphi method was used to establish consensus. Fourteen respiratory physicians and one psychiatrist with strong experience in IAPV use and/or who published manuscripts on the topic participated in the panel. A systematic review of the literature was carried out according to the PRISMA to identify existing evidence on IAPV for patients with neuromuscular disorders. RESULTS: In the first round, 34 statements were circulated. Panel members marked 'agree' or 'disagree' for each statement and provided comments. The agreement was reached after the second voting session for all 34 statements. CONCLUSIONS: Panel members agreed and IAPV indications, parameter settings (including procedure protocol), potential limitations, contraindications, complications, monitoring, and follow-up are described. This is the first expert consensus on IAPV.

Mechanical Insufflation-Exsufflation: The Rest of the Story.

Mechanical insufflation-exsufflation has been reported to decrease pneumonia rates by about 90% for patients with Duchenne muscular dystrophy now living into their 40s and 50s without tracheotomy tubes. It greatly reduces respiratory complications and hospitalization rates to less than one per 10 patient-years for advanced spinal muscular atrophy type 1, through 25-30 years of age. It is most successful from the point at which small children become able to cooperate with it, generally from 3 to 5 years of age. However, since the 1950s, successful use to extubate and decannulate ventilator "unweanable" patients with little to no measurable vital capacity without resorting to tracheostomy has always been at pressures of 50-60 cm H2O via oronasal interfaces and at 60-70 cm H2O via airway tubes when present. It must usually also be used in conjunction with up to continuous noninvasive positive pressure ventilatory support. Centers that use these effectively have eliminated need to resort to tracheotomies for people with muscular dystrophies and spinal muscular atrophies, including unmedicated patients with spinal muscular atrophy type 1. Barotrauma has been rare despite dependence on it and noninvasive ventilatory support. Despite this, noninvasive respiratory management continues to be widely underutilized.

High-Level Spinal Cord Injury and the Failure of US Acute Rehabilitation: An Analysis and Commentary.

ABSTRACT: Acute and long-term morbidity and mortality rates have not changed in the United States for people with high-level spinal cord injury in 40 yrs, neither has the conventional invasive respiratory management for these patients. This is despite a 2006 challenge to institutions for a paradigm shift to avoid or decannulate patients of tracheostomy tubes. Centers in Portugal, Japan, Mexico, and South Korea decannulate high-level patients to up to continuous noninvasive ventilatory support and use mechanical insufflation exsufflation, as we have done and reported since 1990, but there has been no such paradigm shift in US rehabilitation institutions. The quality of life and financial consequences of this are discussed. An example of decannulation of a relatively easy case, after failure to do so during 3 mos of acute rehabilitation, is presented to encourage institutions to begin to learn and apply noninvasive management before decannulating more severe patients with little to no ventilator free breathing ability.

The Intermittent Abdominal Pressure Ventilator as an Alternative Modality of Noninvasive Ventilatory Support: A Narrative Review.

ABSTRACT: Noninvasive ventilation has become the initial treatment for symptomatic ventilatory pump failure but, when used at ventilatory support settings, can be an alternative to tracheostomy mechanical ventilation. The intermittent abdominal pressure ventilator, a corset with an internal air sack inflated by a ventilator, allows to increase tidal volumes through the raising of the diaphragm and its consequent passive descent. It has been used for daytime support for more than 70 yrs, but its knowledge among clinicians is scarce. A narrative review was performed by searching PubMed, Medline, and the Cochrane Database of Systematic Reviews using the terms "IAPV" or "pneumobelt." One hundred forty patients were cited using the intermittent abdominal pressure ventilator from 1946 until it went off the market in the 1970s, although many continued to use it. There was only one publication on its use from 2003 to 2017, but three publications from 2017 through 2021. It has been used for full diurnal ventilatory support by some patients for more than 50 yrs and has even been used throughout the labor of a mother with no ventilator-free breathing ability. The intermittent abdominal pressure ventilator is a ventilatory support alternative for patients with ventilatory pump failure. It can be effective and well tolerated and maintain quality of life without facial interfaces. More widespread application is warranted.

Amyotrophic Lateral Sclerosis and Noninvasive Positive Pressure Ventilatory Support: "Nasal Noninvasive Ventilation" or "Noninvasive Ventilatory Support"?

ABSTRACT: Many studies suggest a brief statistical benefit on survival and quality of life by using nasal noninvasive ventilation for patients with amyotrophic lateral sclerosis and other neuromuscular conditions. Indeed, nasal noninvasive ventilation has become synonymous with continuous positive airway pressure and lo-span bilevel positive airway pressure. Nasal noninvasive ventilation, however, may not normalize CO2 levels and continuous positive airway pressure and O2 exacerbate hypercapnia and often lead to CO2 narcosis, intubation, and ultimately tracheostomy or palliative care death. However, a third option can be to offer up to continuous noninvasive ventilatory support and extubation to it. Noninvasive ventilatory support can be effective for full, definitive ventilatory support, even for people with no measurable vital capacity, and has maintained classic amyotrophic lateral sclerosis patients for up to 12 yrs without resort to tracheotomies. Nineteen centers have reported 335 amyotrophic lateral sclerosis patients using continuous noninvasive ventilatory support instead of tracheostomy mechanical ventilation for an average of 14 mos (6 mos to 14 yrs). The noninvasive ventilatory support must also be used in conjunction with mechanical insufflation-exsufflation to clear airway debris and normalize or renormalize ambient air oxyhemoglobin saturation, both to avoid intubation and to facilitate extubation. People with amyotrophic lateral sclerosis satisfying specific criteria, even when continuously dependent on tracheostomy mechanical ventilation, can be decannulated and placed on continuous noninvasive ventilatory support with mechanical insufflation-exsufflation.

Mechanical Insufflation Exsufflation, Syringomyelia, and Headache.

ABSTRACT: Mechanical insufflation exsufflation creates cough flows to clear central airways secretions for patients with ineffective cough flows. At times, patients with even potentially effective spontaneous cough flows can have pain that prevents effective coughing. We describe a patient with Arnold-Chiari syndrome, syringomyelia, and hydrocephalus who had nine episodes of pneumonia through the age of 9 yrs, and cough associated headaches, who upon using mechanical insufflation exsufflation had no subsequent pneumonias for at least the next 17 yrs and no headaches when using it for coughing.

Proposed Decannulation Criteria for COVID-19 Patients.

ABSTRACT: A 66-yr-old man had been intubated for 21 days for severe COVID-19 infection. He then underwent tracheotomy, retained the tube for 2 mos, and then was discharged home on 10 liters of O2/min breathing via a tracheostomy collar. We were consulted for tracheostomy tube decannulation. Mechanical insufflation-exsufflation was used via the tracheostomy tube to clear secretions, increase vital capacity, and normalize O2 saturation. He practiced nasal and mouthpiece noninvasive ventilatory support once a capped fenestrated cuffless tracheostomy tube was placed, although he did not need noninvasive ventilatory support after decannulation. He was decannulated despite O2 dependence. Although he required antibiotics for almost 3 mos before decannulation and after it, he had no further episodes of lung infection for at least the next 4 mos from the point of decannulation.

Respiratory Complications of Pediatric Neuromuscular Diseases.

Respiration is an event of oxygen consumption and carbon dioxide production. Respiratory failure is common in pediatric neuromuscular diseases and the main cause of morbidity and mortality. It is a consequence of lung failure, ventilatory pump failure, or their combination. Lung failure often is due to chronic aspiration either from above or from below. It may lead to end-stage lung disease. Ventilatory pump failure is caused by increased respiratory load and progressive respiratory muscles weakness. This article reviews the normal function of the respiratory pump, general pathophysiology issues, abnormalities in the more common neuromuscular conditions and noninvasive interventions.

Rehabilitación respiratoria para pacientes con distrofia muscular de Duchenne en etapas de pérdida de la marcha / Respiratory rehabilitation for patients with Duchenne muscular dystrophy in stages of loss of gait

Duchenne muscular dystrophy (DMD) is one of the most common neuromuscular diseases. Its evolution with well-defined stages related to motor and functional alterations, allows easily establishing relationships with respiratory function through a simple laboratory assessment including vital capacity (VC) measurements as well as peak cough flows. Without any treatment with respiratory rehabilitation, the main cause of morbidity and mortality is ventilatory failure, secondary to respiratory pump muscles weakness and inefficient cough. The VC plateau is reached during the non-ambulatory stages, generally after 13 years old. Respiratory rehabilitation protocols, including air stacking techniques, manual and mechanical assisted coughing and non-invasive ventilatory support, can effectively addressed the VC decline as well as the decrease in peak cough flows, despite advancing to stages with practically non-existent lung capacity. Non-invasive ventilatory support may be applied after 19 years old, initially at night and then extending it during the day. In this way, survival is prolonged, with good quality of life, avoiding ventilatory failure, endotracheal intubation and tracheostomy. This article proposes staggered interventions for respiratory rehabilitation based on the functional stages expected in the patient with DMD who has lost ambulation.

La distrofia muscular de Duchenne (DMD) es una de las enfermedades neuromusculares más frecuentes. Su curso evolutivo con etapas de declinación en la funcionalidad motora bien definidas, permite fácilmente establecer relaciones con la función respiratoria a través de un laboratorio de evaluación sencilla, básicamente de la capacidad vital (CV) y la capacidad tusígena. Sin intervenciones en rehabilitación respiratoria, la principal causa de morbimortalidad es la insuficiencia ventilatoria secundaria a debilidad de músculos de la bomba respiratoria e ineficiencia de la tos. En las etapas no ambulantes, se alcanza la meseta de la CV, generalmente después de los 13 años, su declinación junto con la disminución de la capacidad tusígena puede ser enfrentada efectivamente con la utilización de protocolos de rehabilitación respiratoria. Estos deben considerar la restitución de la CV con técnicas de insuflación activa o apilamiento de aire, tos asistida manual y mecánica, más soporte ventilatorio no invasivo, inicialmente nocturno después de los 19 años y luego diurno, pese a avanzar a etapas con capacidad pulmonar prácticamente inexistente. De esta manera, se prolonga la sobrevida, con buena calidad de vida, evitando el fallo ventilatorio, eventos de intubación endotraqueal y traqueostomía. Este artículo, hace propuestas escalonadas de intervención en rehabilitación respiratoria basadas en las etapas funcionales esperables en el paciente con DMD que ha perdido la capacidad de marcha.

Conventional Respiratory Management of Spinal Cord Injury.

Respiratory complications often result from acute spinal cord injury. Ventilatory assistance/support is often required 12 hours to 6 days after admission and is typically delivered via translaryngeal tubes. When not weanable from ventilatory support, tracheostomy tubes are placed. Supplemental O2 is often provided irrespective of whether or not the patient is hypoxic. This renders the oximeter ineffective as a gauge of alveolar ventilation, airway secretion management, and residual lung disease, and can exacerbate hypercapnia. Thus, hypoventilation and airway secretions must be effectively treated to prevent lung disease and to maintain normal O2 saturation and CO2 levels without supplemental O2.

Noninvasive Respiratory Management of Spinal Cord Injury.

Intubated ventilator-dependent patients with high-level spinal cord injury can be managed without tracheostomy tubes provided that they have sufficient cognition to cooperate and that any required surgical procedures are completed and they are medically stable. Intubation for a month or more than extubation to continuous noninvasive ventilatory support (NVS) can be safer long term than resort to tracheotomy. Noninvasive ventilation (NIV) is not conventionally being used for ventilatory support. Noninvasive interfaces include mouthpieces, nasal and oronasal interfaces, and intermittent abdominal pressure ventilators. NIV/NVS should never been used without consideration of mechanical insufflation-exsufflation for airway secretion clearance.

Differentiating Flail Limb Syndrome From Amyotrophic Lateral Sclerosis.

OBJECTIVE: The aim of the study was to investigate differences between flail limb syndrome and amyotrophic lateral sclerosis. DESIGN: A retrospective chart review identified 16 cases of amyotrophic lateral sclerosis and 16 of flail limb syndrome. Revised Amyotrophic Lateral Sclerosis Functional Rating Scale, compound muscle action potential amsplitudes, and rate of loss of vital capacity were compared. RESULTS: Comparing amyotrophic lateral sclerosis and flail limb syndrome patients, rate of loss of vital capacity was 5.26% ± 0.33% versus 0.54% ± 0.06%, respectively (P < 0.05). No patient in the flail limb syndrome group had a rate of loss of vital capacity more than 0.65% per month. No patient in the amyotrophic lateral sclerosis group had a rate of loss of vital capacity less than 4.6% per month. The average ulnar nerve compound muscle action potential amplitudes were significantly lower in flail limb syndrome (P < 0.05). No significant difference was observed in the rate of Revised Amyotrophic Lateral Sclerosis Functional Rating Scale decline or average peroneal, tibial, and median nerve compound muscle action potential amplitudes. CONCLUSIONS: In flail limb syndrome, an average monthly decrease in vital capacity exceeding 0.65% may suggest a spread of motor neuron loss to higher cervical anterior horn areas and raise the possibility of progression to amyotrophic lateral sclerosis. Larger prospective studies are needed to investigate the rate of VC decline in flail limb syndrome and limb-onset amyotrophic lateral sclerosis and to establish whether a cutoff score combining rate of loss of vital capacity and compound muscle action potential amplitude mainly of the ulnar nerve might predict progression of flail limb syndrome to amyotrophic lateral sclerosis, the knowledge of which can facilitate appropriate patient counseling.

Glucocorticoid-Associated Demise of a Patient With Duchenne Muscular Dystrophy.

We describe the clinical deterioration of a 26-yr-old man with Duchenne muscular dystrophy on oral daily high-dose deflazacort. Although this daily regimen was targeted to benefit ambulation and respiration, it resulted in premature death with lethal sequelae from liver failure, decubiti, diabetes mellitus, and morbid obesity. This case illustrates the need for further research weighing risk versus benefit of daily glucocorticoid therapy, specifically deflazacort, in Duchenne muscular dystrophy patients. Thus, curtailment of daily dosing to eliminate dire sequelae in patients living longer into adulthood than ever before is recommended.