Respiratory assistance with a non-invasive ventilator (Bipap) in MND/ALS patients: survival rates in a controlled trial

Neuroprognostication for Patients with Amyotrophic Lateral Sclerosis: An Updated, Evidence-Based Review

Amyotrophic lateral sclerosis (ALS) is a rapidly progressive neurodegenerative disorder that presents and progresses in various ways, making prognostication difficult. Several paradigms exist for providers to elucidate prognosis in a way that addresses not only the amount of time a patient has to live, but also a patient's quality of their life moving forward. Prognostication, with regard to both survivability and quality of life, is impacted by several features that include, but are not limited to, patient demographics, clinical features on presentation, and over time, access to therapy, and access to multidisciplinary clinics. An understanding of the impact that these features have on the life of a patient with ALS can help providers to develop a better and more personalized approach for patients related to their clinical prognosis after a diagnosis is made. The ultimate goal of prognostication is to empower patients with ALS to take control and make decisions with their care teams to ensure that their goals are addressed and met.

Palliative Care in Amyotrophic Lateral Sclerosis

Amyotrophic lateral sclerosis (ALS) is an incurable neurodegenerative disease of the motor neurons. Given the evolutive characteristics of this disease, palliative care principles should be a foundation of ALS care. A multidisciplinary medical intervention is of paramount importance in the different phases of disease. The involvement of the palliative care team improves quality of life and symptoms, and prognosis. Early initiation is of paramount importance to ensuring patient-centered care, when the patient has still the capability to communicate effectively and participate in his medical care. Advance care planning supports patients and family members in understanding and sharing their preferences according to their personal values and life goals regarding future medical treatment. The principal problems which require intensive supportive care include cognitive disturbances, psychological distress, pain, sialorrhrea, nutrition, and ventilatory support. Communication skills of health-care professionals are mandatory to manage the inevitability of death. Palliative sedation has peculiar aspects in this population, particularly with the decision of withdrawing ventilatory support.

Current State and Future Directions in the Therapy of ALS

Amyotrophic lateral sclerosis (ALS) is a rapidly progressive neurodegenerative disorder affecting upper and lower motor neurons, with death resulting mainly from respiratory failure three to five years after symptom onset. As the exact underlying causative pathological pathway is unclear and potentially diverse, finding a suitable therapy to slow down or possibly stop disease progression remains challenging. Varying by country Riluzole, Edaravone, and Sodium phenylbutyrate/Taurursodiol are the only drugs currently approved in ALS treatment for their moderate effect on disease progression. Even though curative treatment options, able to prevent or stop disease progression, are still unknown, recent breakthroughs, especially in the field of targeting genetic disease forms, raise hope for improved care and therapy for ALS patients. In this review, we aim to summarize the current state of ALS therapy, including medication as well as supportive therapy, and discuss the ongoing developments and prospects in the field. Furthermore, we highlight the rationale behind the intense research on biomarkers and genetic testing as a feasible way to improve the classification of ALS patients towards personalized medicine.

Respiratory onset in amyotrophic lateral sclerosis: clinical features and spreading pattern

Objective To describe the clinical features and progression of patients with respiratory onset amyotrophic lateral sclerosis (ALS). Methods: We analyzed the clinical features, including respiratory tests, functional score, noninvasive ventilation (NIV) time and survival of ALS patients with respiratory-onset in our database consisting of 1688 patients. In a subset of 625 ALS patients we analyzed the spreading pattern to other bodily regions. Results: We included 1579 patients with ALS. Sixty-three patients (4%) presented respiratory-onset (79.4% men, mean onset-age 67.7 ± 8.9yrs). All had predominant LMN involvement, and significant weight loss (>10%) was identified in 38.9%. The respiratory tests were abnormal in these respiratory-onset patients (p < 0.001). ALSFRS-R respiratory subscore was lower in this population (p < 0.001). NIV was adapted in 84.1%, sooner than in the larger group of ALS patients (p < 0.001), and survival from disease onset was shorter (p < 0.001). Respiratory-onset was a predictor of time to NIV (X²=42.0, p < 0.001) and of survival (X²=7.1, p = 0.008). The spreading pattern was studied in 18 patients with isolated respiratory-onset. The progression interval to the 2nd region was 4.7 ± 5.7mo and to a 3rd region 6.1 ± 8.7mo. Different patterns of spread had no impact on survival. Conclusions: This phenotype is typically seen in emaciated older men with predominant lower motor neuron involvement, and is associated with diaphragm paresis and central respiratory involvement. NIV adaptation is rapid but total survival is shorter than in the other patients. Spreading pattern did not affect time to NIV adaptation or total survival, as NIV support is a modifying treatment in the course of ALS.

Outpatient neuropalliative care

Palliative care is an approach to patient care that focuses on enhancing quality of life through relief of physical, emotional, and spiritual sources of distress and patient-tailored discussions about goals of care. The palliative care approach can be delivered by any provider, and can occur alongside disease-modifying therapies. For patients with a serious neurologic illness or a neurodegenerative disease, neuropalliative care is a growing field focused on providing high-quality palliative care to neurology patients. There are three models of neuropalliative care delivery in the outpatient setting: a consultative model with a palliative care specialist, an integrated model with an embedded palliative care provider, and a primary palliative care model with the patient's neurology provider. The main components of an outpatient palliative care visit include symptom assessment and treatment, communication about serious illness, advance care planning, and assessment of caregiver needs. For patients with advanced illness, palliative care can help facilitate timely referral to hospice. Through a palliative care approach, outpatient care for patients with serious neurologic disease or neurodegenerative disease can focus on the issues most important to the patient, promote improved illness understanding and planning, and can improve the overall quality of care.

Immediate postoperative non-invasive positive pressure ventilation following midface microvascular free flap reconstruction

BACKGROUND

There is a rare need for postoperative non-invasive positive pressure ventilation (NIPPV) following microvascular reconstruction of the head and neck. In midface reconstruction, the free flap vascular pedicle is especially vulnerable to the compressive forces of positive pressure delivery.

CASE

A 60 year old female with Amyotrophic Lateral Sclerosis (ALS) presented with squamous cell carcinoma of the anterior maxilla, for which she underwent infrastructure maxillectomy and fibula free flap reconstruction. To avoid tracheotomy, the patient was extubated postoperatively and transitioned to NIPPV immediately utilizing a full-face positive pressure mask with a soft and flexible sealing layer. The patient was successfully transitioned to NIPPV immediately after extubation. The free flap exhibited no signs of vascular compromise postoperatively, and healed very well.

CONCLUSION

Postoperative non-invasive positive pressure ventilation can be successfully applied following complex microvascular midface reconstruction to avoid tracheotomy in select patients without vascular compromise of the free flap.

Noninvasive and invasive mechanical ventilation for neurologic disorders

Patients with acute neurologic injuries frequently require mechanical ventilation due to diminished airway protective reflexes, cardiopulmonary failure secondary to neurologic insults, or to facilitate gas exchange to precise targets. Mechanical ventilation enables tight control of oxygenation and carbon dioxide levels, enabling clinicians to modulate cerebral hemodynamics and intracranial pressure with the goal of minimizing secondary brain injury. In patients with acute spinal cord injuries, neuromuscular conditions, or diseases of the peripheral nerve, mechanical ventilation enables respiratory support under conditions of impending or established respiratory failure. Noninvasive ventilatory approaches may be carefully considered for certain disease conditions, including myasthenia gravis and amyotrophic lateral sclerosis, but may be inappropriate in patients with Guillain-Barré syndrome or when relevant contra-indications exist. With regard to discontinuing mechanical ventilation, considerable uncertainty persists about the best approach to wean patients, how to identify patients ready for extubation, and when to consider primary tracheostomy. Recent consensus guidelines highlight these and other knowledge gaps that are the focus of active research efforts. This chapter outlines important general principles to consider when initiating, titrating, and discontinuing mechanical ventilation in patients with acute neurologic injuries. Important disease-specific considerations are also reviewed where appropriate.

Use of non-invasive ventilation in motor neuron disease - a retrospective cohort analysis

Motor neuron disease (MND) is a neurodegenerative disorder which leads to progressive muscle weakness including respiratory muscle decline. The introduction of non-invasive ventilation (NIV) has been shown to improve quality of life, survival and slow the rate of pulmonary function decline. A retrospective chart analysis of patients who attended the MND clinic from 2014 to 2019 at a tertiary-referral, academic, teaching hospital was carried out to evaluate if NIV and greater compliance with NIV was associated with improved survival. 111 patients were included. The mean age at diagnosis was 63.8 years and 61.3% were males. 66.7% of our cohort used NIV and of this 66.7%, 44.1% were compliant. There was a significantly longer survival in those who used NIV (p = 0.002) and in those who used NIV optimally (p = 0.02) when both groups were compared to those who did not use NIV. In the bulbar MND group those who were compliant with NIV survived longer than who those who did not use NIV (p = 0.001). We found a significantly longer survival with the use of NIV, the use of NIV optimally and with use of NIV in those with bulbar onset MND compared to those who did not use NIV.

Medical therapies for amyotrophic lateral sclerosis-related respiratory decline: an appraisal of needs, opportunities and obstacles

A roundtable convened in July 2020 examined issues concerning respiratory support in amyotrophic lateral sclerosis (ALS), with reference to the potential for an early-phase orally administered medication that might either postpone the introduction of noninvasive ventilation (NIV) and/or enhance the benefits to be gained from it. Attention was also given to the impact of the COVID-19 pandemic on usual practice in the assessment and management of ALS-related respiratory difficulties. Implementation of NIV marks a step-change in clinical status for patients and a major increase in burden for caregivers. All means to ease this transition should be explored: an oral therapy that supported respiratory function and patients' independence and sense of well-being would aid discussions to facilitate the eventual successful introduction of NIV. Assessment of a candidate oral therapy that might support respiratory function in ALS patients would be aided by the development of improved patient-reported outcome measures for robust quantification of treatment effect and quality of life. Such instruments could also be used to monitor patients' status during the COVID-19 pandemic, averting some of the risks of face-to-face assessment plus the patient burden and costs of traditional methods. Several oral candidate therapies have recently failed to meet their primary endpoints in clinical trials. However, understanding of the underlying physiology and appropriate trial design have grown and will inform future developments in this field.

Noninvasive Ventilation in Amyotrophic Lateral Sclerosis

Amyotrophic lateral sclerosis is a progressive neurodegenerative disease involving upper and lower motor neurons and has limited treatment options. The weakness progresses to involve the diaphragms, resulting in respiratory failure and death. Home noninvasive ventilation has been shown to improve survival and quality of life, especially in those with intact bulbar function. Once initiated, close monitoring with nocturnal oximetry, remote downloads from the home noninvasive ventilation machine, and measurement of serum bicarbonate should be conducted. Additionally, transcutaneous CO2 monitoring can be considered if available. This article discusses the indications, timing, initiation, and management of noninvasive ventilation in amyotrophic lateral sclerosis.

The Benefit of Non-invasive Ventilation in Motor Neuron Disease

Background:

Motor Neuron Disease (MND) is a progressive neurodegenerative disorder leading to respiratory muscle weakness with dyspnoea, morning headaches, orthopnoea, poor concentration, unrefreshing sleep, fatigue and daytime somnolence. Respiratory failure is the primary cause of death in those with MND.

Methods:

Although guidelines suggest the use of non-invasive ventilation (NIV) in MND, there lacks clear guidance as to when is the optimal time to initiate NIV and which markers of respiratory muscle decline are the best predictors of prognosis. There have been a number of studies that have found a significant survival advantage to the use of NIV in MND. Similarly, in quality-of-life questionnaires, those treated with NIV tend to perform better and maintain a better quality of life for longer. Furthermore, studies also suggest that improved compliance and greater tolerance of NIV confer a survival advantage.

Results and Discussion:

Forced Vital Capacity (FVC) has traditionally been the main pulmonary function test to determine the respiratory function in those with MND; however, FVC may not be entirely reflective of early respiratory muscle dysfunction. Evidence suggests that sniff nasal inspiratory pressure and maximum mouth inspiratory pressure may be better indicators of early respiratory muscle decline. These measures have been shown to be easier to perform later in the disease, in patients with bulbar onset disease, and may indeed be better prognostic indicators.

Conclusion:

Despite ongoing research, there remains a paucity of randomised controlled data in this area. This review aims to summarise the evidence to date on these topics.

Respiratorische Ereigniserkennung unter nichtinvasiver Beatmung (NIV) in Abhängigkeit von der genutzten Flowmessung

Hintergrund

Beim chronisch hyperkapnischem Atemversagen stellt die nächtliche nichtinvasive Beatmung (NIV) die Standardtherapie dar. Die Einstellung auf die NIV erfordert jedoch viel Erfahrung. Nur eine Polysomnografie (PSG) im Schlaflabor ermöglicht die genaue Analyse von residualen Obstruktionen der oberen Atemwege, zentralen Apnoen, Triggerfehlfunktionen und Leckagen. Die Flowmessung unter NIV ist technisch jedoch nicht einfach, insbesondere da normierte Schnittstellen zur Einbindung der Respiratoren in die PSG fehlen.

Ziel der Arbeit

Vergleich eines Druck‑/Flow-Monitors mit den Signalen aus den Schnittstellen der Respiratoren bezüglich der Erkennung sowohl von Apnoen/Hypopnoen als auch von NIV-spezifischen Ereignissen in der PSG.

Methoden

Retrospektiv wurden 20 Aufzeichnungen von Patienten unter NIV, die unter einem standardisierten Protokoll aufgezeichnet worden waren, erneut verblindet ausgewertet. Es erfolgte ein Vergleich der Auswertung dreier verschiedener Verfahren der Flowmessung (effortbasiert, Staudruckmessung, Schnittstelle) hinsichtlich der Häufigkeit von respiratorischen Ereignissen.

Ergebnisse

Durch eine einfach zu integrierende Staudruckmessung mittels Druck‑/Flow-Monitor waren signifikant weniger Ereignisse diagnostizierbar, als wenn der Flow über die Abdomen- und Thoraxgurte oder über die Schnittstelle zu den Respiratoren ermittelt wurde. Auch die NIV-induzierten Ereignisse wie Fehltriggerungen oder Leckagen ließen sich nur mittels der Schnittstelle zuverlässig erkennen.

Schlussfolgerung

Eine Messung des Flows mit einem Standard Druck‑/Flow-Monitor bietet keine ausreichend nachvollziehbaren Ergebnisse. Eine Einbindung des Beatmungsgeräts in die PSG über eine Schnittstelle ist daher zu fordern.

Which are the factors influencing NIV adaptation and tolerance in ALS patients?

Amyotrophic lateral sclerosis (ALS) is a multisystemic disease compromising both the neuromuscular system and the cognitive status. Non-invasive ventilation (NIV) has been shown to improve survival and quality of life in ALS patients with respiratory failure, but scanty literature investigated which are the predictors of NIV tolerance. The aim of this study was to evaluate the impact of functional, cognitive, neurobehavioral, and respiratory status on NIV compliance and tolerance in patients with ALS. We retrospectively evaluated clinical data of ALS patients who consecutively underwent a NIV trial during hospitalization. Cognitive and neurobehavioral assessments have been performed using the Edinburgh Cognitive and Behavioral ALS Screen (ECAS), the Hospital Anxiety and Depression Scale (HADS), the Frontal Assessment Battery (FAB), the Raven's 47 Colored Progressive Matrices (PM47), and the Neurobehavioral Rating Scale Revised (NRSR). Seventy-two patients (mean age ± SD; 63.9 ± 10.6 years) were included. Patients adapted were 63/72 (87.5%). The average time of adaptation was 7.82 ± 5.27 days. The time required to reach a satisfying NIV adaptation was significantly related to the presence of sialorrhea (p = 0.02), respiratory status (Borg Dyspnoea Scale, p = 0.006, and ALS-FRS-R respiratory subscore, p = 0.03) and behavioral and cognitive impairment (NRSR-F1, p = 0.04, NRSR- F5, p = 0.04). Presence of sialorrhea and neurobehavioral impairment, and absence of respiratory symptoms are negative predictors of NIV adaptation. This study highlights the need of a multidisciplinary patient-tailored approach including cognitive-behavioral assessment and a psychological support program to optimize patient's training and compliance to NIV.

The Role of Radiation Therapy and Botulinum Toxin Injections in the Management of Sialorrhea in Patients With Amyotrophic Lateral Sclerosis: A Systematic Review

OBJECTIVES

Half of patients with amyotrophic lateral sclerosis experience sialorrhea due to facial weakness. Although anticholinergic medications are first-line therapy, they often lead to unacceptable side effects. Radiation therapy and botulinum toxin may be considered when medical management fails. In this systematic review, we investigated the effectiveness of these interventions.

METHODS

Eligible studies were retrieved from PubMed and Scopus databases up to March 2017 along with hand-searching of references from primary articles.

RESULTS

Fourteen studies (N = 138) examined the benefits of botulinum toxin. Studies varied in salivary glands treated, dosages used, and the use of botulinum toxin subtype A or B. A majority of studies showed benefit after treatment. Although most studies reported only mild adverse effects, 2 case studies revealed severe complications including recurrent TMJ dislocations and rapid deterioration in bulbar function. Ten studies (N = 171) examined the benefits of radiation. Most studies reported improvement with only mild adverse events reported.

CONCLUSIONS

Both radiation and botulinum toxin are effective treatments for sialorrhea in patients with amyotrophic lateral sclerosis and should be considered when medical management fails. Radiation may offer longer duration of symptom improvement with fewer complications.

Sleep and Sleep Disruption in Amyotrophic Lateral Sclerosis

PURPOSE OF REVIEW

In amyotrophic lateral sclerosis (ALS), sleep disruption is frequently present and substantially adds to disease burden. This review aims to summarize current knowledge on causes, pathophysiology, and treatment of sleep disturbances in ALS.

RECENT FINDINGS

Motor neuron degeneration and muscle weakness may lead to muscle cramps, pain, spasticity, immobilization, restless legs, sleep-disordered breathing, and difficulties to clear secretions. Furthermore, existential fears and depression may promote insomnia. Sleep-disordered breathing, and nocturnal hypoventilation in particular, requires ventilatory support which meaningfully prolongs survival and improves health-related quality of life albeit respiratory failure is inevitable. Early indication for non-invasive ventilation can be achieved by inclusion of capnometry in diagnostic sleep studies. Sleep disruption is extremely common in ALS and may arise from different etiologies. The absence of causative therapeutic options for ALS underlines the importance of symptomatic and palliative treatment strategies that acknowledge sleep-related complaints.

Effects of noninvasive ventilation in amyotrophic lateral sclerosis: The complication of bulbar impairment

Amyotrophic lateral sclerosis is a neurodegenerative illness that causes gradual loss of muscle function. Patients eventually develop bulbar impairment, requiring extensive respiratory support. Noninvasive ventilation (NIV) has gained attention as an easily accessible method with promising benefits. We conducted this systematic review to outline the therapeutic effects of NIV, add to previous publications discussing this topic by providing updates on newly completed and ongoing studies, and identify limitations that must be addressed in future trials. A search of PubMed and Cochran for relevant primary studies yielded 26 publications. Studies indicate NIV use is associated with improvements in quality of life, regardless of the severity of bulbar impairment. However, NIV’s benefits on survival were limited to patients with less bulbar impairment. In addition, our review found several limitations that undermine the efforts to establish a definitive treatment regimen. Future studies will need to address these problems in order to provide patients with better respiratory care.

Quality of life and functional independence in amyotrophic lateral sclerosis: A systematic review

Amyotrophic Lateral Sclerosis (ALS) leads to functional capacity decline, generating great impact in quality of life. Quality of life is directly related to physical integrity and functional independence. This systematic review aimed to analyze treatment protocols and their outcomes from clinical trials with focus on ALS rehabilitation that evaluated the effects on quality of life and functional independence from their intervention process. A literature search was conducted through MEDLINE-PubMed, Science Direct, Web of Science and Scopus databases. A total of 3630 articles were identified. Eleven studies met the inclusion criteria. They focused on different aspects of quality of life or functional independence, which are: respiratory care, mental health, communication skills and exercises. Use of bipap and inspiratory muscle training, anxiety and depression, communication devices implementation and exercises safety and tolerability were considered as key points. However, the drastic evolution of the disease is a limiting factor to the perception of quality of life improvement by patients. Further studies should be done to validate the benefits on patients' quality of life.

Suppressed N fixation and diazotrophs after four decades of fertilization

BACKGROUND

N fixation is one of the most important microbially driven ecosystem processes on Earth, allowing N to enter the soil from the atmosphere, and regulating plant productivity. A question that remains to be answered is whether such a fundamental process would still be that important in an over-fertilized world, as the long-term effects of fertilization on N fixation and associated diazotrophic communities remain to be tested. Here, we used a 35-year fertilization experiment, and investigated the changes in N fixation rates and the diazotrophic community in response to long-term inorganic and organic fertilization.

RESULTS

It was found that N fixation was drastically reduced (dropped by 50%) after almost four decades of fertilization. Our results further indicated that functionality losses were associated with reductions in the relative abundance of keystone and phylogenetically clustered N fixers such as Geobacter spp.

CONCLUSIONS

Our work suggests that long-term fertilization might have selected against N fixation and specific groups of N fixers. Our study provides solid evidence that N fixation and certain groups of diazotrophic taxa will be largely suppressed in a more and more fertilized world, with implications for soil biodiversity and ecosystem functions.

Sleep in chronic respiratory disease: COPD and hypoventilation disorders

COPD and obstructive sleep apnoea (OSA) are highly prevalent and different clinical COPD phenotypes that influence the likelihood of comorbid OSA. The increased lung volumes and low body mass index (BMI) associated with the predominant emphysema phenotype protects against OSA whereas the peripheral oedema and higher BMI often associated with the predominant chronic bronchitis phenotype promote OSA. The diagnosis of OSA in COPD patients requires clinical awareness and screening questionnaires which may help identify patients for overnight study. Management of OSA-COPD overlap patients differs from COPD alone and the survival of overlap patients treated with nocturnal positive airway pressure is superior to those untreated. Sleep-related hypoventilation is common in neuromuscular disease and skeletal disorders because of the effects of normal sleep on ventilation and additional challenges imposed by the underlying disorders. Hypoventilation is first seen during rapid eye movement (REM) sleep before progressing to involve non-REM sleep and wakefulness. Clinical presentation is nonspecific and daytime respiratory function measures poorly predict nocturnal hypoventilation. Monitoring of respiration and carbon dioxide levels during sleep should be incorporated in the evaluation of high-risk patient populations and treatment with noninvasive ventilation improves outcomes.

Sleep disturbances in patients with amyotrophic lateral sclerosis: current perspectives

Amyotrophic lateral sclerosis (ALS) is a progressive motor neuron disease inevitably leading to generalized muscle weakness and premature death. Sleep disturbances are extremely common in patients with ALS and substantially add to the burden of disease for both patients and caregivers. Disruption of sleep can be caused by physical symptoms, such as muscle cramps, pain, reduced mobility, spasticity, mucus retention, and restless legs syndrome. In addition, depression and anxiety may lead to significant insomnia. In a small subset of patients, rapid eye movement (REM) sleep behavioral disorder may be present, reflecting neurodegeneration of central nervous system pathways which are involved in REM sleep regulation. With regard to overall prognosis, sleep-disordered breathing (SDB) and nocturnal hypoventilation (NH) are of utmost importance, particularly because NH precedes respiratory failure. Timely mechanical ventilation is one of the most significant therapeutic measures to prolong life span in ALS, and transcutaneous capnometry is superior to pulse oxymetry to detect NH early. In addition, it has been shown that in patients on home ventilatory support, survival time depends on whether normocapnia, normoxia, and elimination of apneic events during sleep can be reliably achieved. Several studies have investigated sleep patterns and clinical determinants of sleep disruption in ALS, but exact prevalence numbers are unknown. Thus, constant awareness for sleep-related symptoms is appropriate. Since no curative treatment can be offered to affected patients, sleep complaints should be thoroughly investigated in order to identify any treatable etiology and improve or stabilize quality of life as much as possible. The use of hypnotics should be confined to palliation during the terminal phase and refractory insomnia in earlier stages of the disease, taking into account that most compounds potentially aggravate SDB.

NIV in amyotrophic lateral sclerosis: The 'when' and 'how' of the matter

Non-invasive ventilation (NIV) has become an essential part of the treatment of amyotrophic lateral sclerosis (ALS) since 2006. NIV very significantly improves survival, quality of life and cognitive performances. The initial NIV settings are simple, but progression of the disease, ventilator dependence and upper airway involvement sometimes make long-term adjustment of NIV more difficult, with a major impact on survival. Unique data concerning the long-term adjustment of NIV in ALS show that correction of leaks, management of obstructive apnoea and adaptation to the patient's degree of ventilator dependence improve the prognosis. Non-ventilatory factors also impact the efficacy of NIV and various solutions have been described and must be applied, including cough assist techniques, control of excess salivation and renutrition. NIV in ALS has been considerably improved as a result of application of all of these measures, avoiding the need for tracheostomy in the very great majority of cases. More advanced use of NIV also requires pulmonologists to master the associated end-of-life palliative care, as well as the modalities of discontinuing ventilation when it becomes unreasonable.

Sialorrhea in patients with ALS: current treatment options

Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disorder of the motor neuron, which selectively affects it both at central (first motor-neuron) and peripheral level (second motor-neuron). The disease shows up at a mean age of 56 years and the most affected are males. Although ALS may start as a bulbar or spinal disease, with the progression of the disease typically both become evident. Pharmacological approved treatments for ALS are still limited and include riluzole and edaravone which improve survival over time. Despite this, ALS leads to progressive muscle involvement and requires a complex multidisciplinary approach to manage increasing disability which goes beyond motor neurons. Sialorrhea is, amongst others, one of the most disabling symptoms in ALS. The complexity in managing saliva is due to a muscular spasticity and to a scarce palatino-lingual muscles control, rather than to an overproduction of saliva. These features could increase the risk of aspiration pneumonia and limit the use of noninvasive mechanical ventilation. We reviewed the treatment for sialorrhea in ALS patients that are available at this time, emphasizing pros and cons for each approach. Our purpose is to create a practical tool for the diagnosis, in order to facilitate the quantification and management of sialorrhea in everyday practice.

Amyotrophic Lateral Sclerosis and the Respiratory System

Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disorder that always affects the respiratory muscles. It is characterized by degeneration of motor neurons in the brain and spinal cord. Respiratory complications are the most common causes of death in ALS and typically occur within 3 to 5 years of diagnosis. Because ALS affects both upper and lower motor neurons, it causes hyperreflexia, spasticity, muscle fasciculations, muscle atrophy, and weakness. It ultimately progresses to functional quadriplegia. ALS most commonly begins in the limbs, but in about one-third of cases it begins in the bulbar muscles responsible for speech and swallowing.

Prognostic Nomogram Associated with Longer Survival in Amyotrophic Lateral Sclerosis Patients

Better understanding of survival factors in amyotrophic lateral sclerosis (ALS) could help physicians and patients schedule therapeutic interventions. We conducted a study to evaluate the predictive factors associated with longer survival and construct prognostic nomogram in ALS patients. A total of 553 ALS patients were enrolled and divided into 2 groups: a training set and a validation set. Risk factors for survival were identified using logistic regression analysis, and a nomogram created by R program was performed to predict the probability of longer survival in the training set; then receiver operating characteristic (ROC) analysis was applied to assess predictive value of the nomogram model. The median survival time was 3.2 years for all patients. Multivariate analyses revealed that age of onset, rate of disease progression, hemoglobin A1c (HbA1c) level, body mass index, creatinine, creatine kinase (CK), and non-invasive positive pressure ventilation (NIPPV) were independent predictors of longer survival. A nomogram based on the above seven predictive factors was developed to predict the possibility of longer survival. The ROC curve of the nomogram demonstrated good discrimination ability with an AUC of 0.92 (95% CI: 0.88-0.96) in the validation set. In ALS, serum CK, creatinine and HbA1c levels at baseline were independent biomarkers of longer survival. The prognostic nomogram model that integrated all significant independent factors for those who survived longer than 3 years provides an effective way to predict the probability of longer survival and can help doctors evaluate the disease progression and give personalized treatment recommendations.

Associative Increases in Amyotrophic Lateral Sclerosis Survival Duration With Non-invasive Ventilation Initiation and Usage Protocols

Objective: It is hypothesized earlier non-invasive (NIV) ventilation benefits Amyotrophic Lateral Sclerosis (ALS) patients. NIV typically consists of the removable bi-level positive airway pressure (Bi-PAP) for adjunctive respiratory support and/or the cough assist intervention for secretion clearance. Historical international standards and current USA insurance standards often delay NIV until percent predicted forced vital capacity (FVC %predict) is <50. We identify the optimal point for Bi-PAP initiation and the synergistic benefit of daily Bi-PAP and cough assist on associative increases in survival duration.

Methods: Study population consisted of a retrospective ALS cohort (Emory University, Atlanta, GA, USA). Primary analysis included 474 patients (403 Bi-PAP users, 71 non-users). Survival duration (time elapsed from baseline onset until death) is compared on the basis of Bi-PAP initiation threshold (FVC %predict); daily Bi-PAP usage protocol (hours/day); daily cough assist usage (users or non-users); ALS onset type; ALSFRS-R score; and time elapsed from baseline onset until Bi-PAP initiation, using Kruskal-Wallis one-way analysis of variance and Kaplan Meier.

Results: Bi-PAP users' median survival (21.03 months, IQR = 23.97, N = 403) is significantly longer (p < 0.001) than non-users (13.84 months, IQR = 11.97, N = 71). Survival consistently increases (p < 0.01) with FVC %predict Bi-PAP initiation threshold: <50% (20.3 months); ≥50% (23.60 months); ≥80% (25.36 months). Bi-PAP usage >8 hours/day (23.20 months) or any daily Bi-PAP usage with cough assist (25.73 months) significantly (p < 0.001) extends survival compared to Bi-PAP alone (15.0 months). Cough assist without Bi-PAP has insignificant impact (14.17 months) over no intervention (13.68 months). Except for bulbar onset Bi-PAP users, higher ALSFRS-R total scores at Bi-PAP initiation significantly correlate with higher initiation FVC %predict and longer survival duration. Time elapsed since ALS onset is not a good predictor of when NIV should be initiated.

Conclusions: The “optimized” NIV protocol (Bi-PAP initiation while FVC %predict ≥80, Bi-PAP usage >8 h/day, daily cough assist usage) has a 30. 8 month survival median, which is double that of a “standard” NIV protocol (initiation FVC %predict <50, usage >4 h/day, no cough assist). Earlier access to Bi-PAP and cough assist, prior to precipitous respiratory decline, is needed to maximize NIV synergy and associative survival benefit.

Diaphragmatic Palsy

The diaphragm is the primary muscle of respiration, and its weakness can lead to respiratory failure. Diaphragmatic palsy can be caused by various causes. Injury to the phrenic nerve during thoracic surgeries is the most common cause for diaphragmatic palsy. Depending on the cause, the symptoms of diaphragmatic palsies vary from completely asymptomatic to disabling dyspnea requiring mechanical ventilation. On pulmonary function tests, there will be a decrease in the maximum respiratory muscle power. Spirometry shows reduced lung functions and a significant drop of lung function in supine position is typical of diaphragmatic palsy. Diaphragmatic movements with respiration can be directly visualized by fluoroscopic examination. Currently, this test is being replaced by bedside thoracic ultrasound examination, looking at the diaphragmic excursion with deep breathing or sniffing. This test is found to be equally efficient, and without risks of ionizing radiation of fluoroscope. Treatment of diaphragmatic palsy depends on the cause. Surgical approach of repair of diaphragm or nonsurgical approach of noninvasive ventilation has been tried with good success. Overall prognosis of diaphragmatic palsy is good, except when it is related to neuromuscular degeneration conditions.

The Role of Moderate Aerobic Exercise as Determined by Cardiopulmonary Exercise Testing in ALS

Introduction

The efficacy of cardiopulmonary exercise testing (CPET) to determining exercise intensity has not been established in Amyotrophic Lateral Sclerosis (ALS). We studied this intervention.

Methods

We included 48 ALS patients randomized in 2 groups: G1 (n = 24), exercise intensity leveled by CPET; G2 (n = 24), standard care limited by fatigue, during 6 months. ALS functional scale (ALSFRS-R) and forced vital capacity (FVC) were performed every 3 months; CPET was done at admission (T1) and 6 months later (T2). We registered oxygen uptake, carbon dioxide output, and ventilation at anaerobic threshold and at peak effort. Primary outcome was functional change. We used parametric statistics for comparisons and multiple regression analyses to identify independent predictors of functional decline.

Results

At T1 both groups were identical, except for higher FVC in G1 (p = 0.02). At T2, ALSFRS-R was higher (p = 0.035) in G1. Gas exchange variables at T2 did not change in G1 but had significant differences in G2 (p < 0.05). Multiregression analyses showed the Spinal ALSFRS-R slope and Intervention group (p < 0.001) as significant predictors of ALSFRS-R at T2.

Conclusion

Aerobic exercise defined by CPET is feasible and can improve functional outcome in ALS. This trial is registered with Clinical trials.gov ID: NCT03326622.

Home Mechanical Ventilation: An Overview

Prevalence studies have shown heterogeneous use of home mechanical ventilation in different conditions, with a marked increase in uptake especially in users of noninvasive ventilation. Although randomized controlled trials have examined noninvasive ventilation in acute exacerbations of chronic obstructive pulmonary disease, for weaning from invasive ventilation and for postextubation respiratory failure, the evidence base for long-term noninvasive ventilation and comparisons with invasive ventilation are less well developed. The combination of noninvasive ventilation and cough-assist devices has reduced the indications for tracheotomy ventilation in some situations (e.g., Duchenne muscular dystrophy, spinal muscular atrophy, myopathies, and amyotrophic lateral sclerosis) and has also prolonged survival. Several excellent overviews have been written on the history of home mechanical ventilation and its evolution from negative pressure to positive pressure techniques, including a systematic review of outcomes. This review, instead, will cover recent trials, trends in the field, outcomes, and safety. Because the greatest growth has been in home noninvasive ventilation, this will be the main focus of this article.

A randomized controlled trial of resistance and endurance exercise in amyotrophic lateral sclerosis

OBJECTIVE

Evaluate the safety and tolerability of resistance and endurance exercise in ALS participants as measured by their ability to complete this six-month study.

METHODS

Participants were randomized to Resistance, Endurance, or Stretching/Range of Motion (SROM the exercise regimen prescribed for most ALS patients) exercises. All exercises were performed at home with an individualized regimen designed by a physical therapist trained in ALS management. Primary outcome measures were tolerability of the exercises at 24 weeks defined by 50% of participants completing at least 50% of the prescribed exercise regimen. Secondary outcome measures included the ALSFRS-R, pulmonary FVC, and other measures of ALS function.

RESULTS

At 12 and 24 weeks, all three exercise regimens were tolerated according to our pre-specified criteria. Compliance to the prescribed exercise regimen was the highest in the resistance and SROM arms of the study. All three forms of exercise were considered safe as there were no differences in the rates of disease progression among groups. There were no differences in the secondary outcome measures and feasibility for evaluating these measures was successful. In a post-hoc analysis, there was a trend towards fewer falls in the Resistance and Endurance groups.

CONCLUSIONS

This study demonstrates that SROM, resistance, and endurance exercise are all safe to be performed with the specified regimen without any worsening of outcomes as related to ALS function. All three forms of exercise were tolerated with resistance and SROM exercises showing the highest compliance over the 24 week-period.

Mechanical ventilation for amyotrophic lateral sclerosis/motor neuron disease

BACKGROUND

Amyotrophic lateral sclerosis (ALS), also known as motor neuron disease, is a fatal neurodegenerative disease. Neuromuscular respiratory failure is the most common cause of death, which usually occurs within two to five years of the disease onset. Supporting respiratory function with mechanical ventilation may improve survival and quality of life. This is the second update of a review first published in 2009.

OBJECTIVES

To assess the effects of mechanical ventilation (tracheostomy-assisted ventilation and non-invasive ventilation (NIV)) on survival, functional measures of disease progression, and quality of life in ALS, and to evaluate adverse events related to the intervention.

SEARCH METHODS

We searched the Cochrane Neuromuscular Specialised Register, the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase, CINAHL Plus, and AMED on 30 January 2017. We also searched two clinical trials registries for ongoing studies.

SELECTION CRITERIA

Randomised controlled trials (RCTs) and quasi-RCTs involving non-invasive or tracheostomy-assisted ventilation in participants with a clinical diagnosis of ALS, independent of the reported outcomes. We included comparisons with no intervention or the best standard care.

DATA COLLECTION AND ANALYSIS

For the original review, four review authors independently selected studies for assessment. Two review authors reviewed searches for this update. All review authors independently extracted data from the full text of selected studies and assessed the risk of bias in studies that met the inclusion criteria. We attempted to obtain missing data where possible. We planned to collect adverse event data from the included studies.

MAIN RESULTS

For the original Cochrane Review, the review authors identified two RCTs involving 54 participants with ALS receiving NIV. There were no new RCTs or quasi-RCTs at the first update. One new RCT was identified in the second update but was excluded for the reasons outlined below.Incomplete data were available for one published study comparing early and late initiation of NIV (13 participants). We contacted the trial authors, who were not able to provide the missing data. The conclusions of the review were therefore based on a single study of 41 participants comparing NIV with standard care. Lack of (or uncertain) blinding represented a risk of bias for participant- and clinician-assessed outcomes such as quality of life, but it was otherwise a well-conducted study with a low risk of bias.The study provided moderate-quality evidence that overall median survival was significantly different between the group treated with NIV and the standard care group. The median survival in the NIV group was 48 days longer (219 days compared to 171 days for the standard care group (estimated 95% confidence interval 12 to 91 days, P = 0.0062)). This survival benefit was accompanied by an enhanced quality of life. On subgroup analysis, in the subgroup with normal to moderately impaired bulbar function (20 participants), median survival was 205 days longer (216 days in the NIV group versus 11 days in the standard care group, P = 0.0059), and quality of life measures were better than with standard care (low-quality evidence). In the participants with poor bulbar function (21 participants), NIV did not prolong survival or improve quality of life, although there was significant improvement in the mean symptoms domain of the Sleep Apnea Quality of Life Index by some measures. Neither trial reported clinical data on intervention-related adverse effects.

AUTHORS' CONCLUSIONS

Moderate-quality evidence from a single RCT of NIV in 41 participants suggests that it significantly prolongs survival, and low-quality evidence indicates that it improves or maintains quality of life in people with ALS. Survival and quality of life were significantly improved in the subgroup of people with better bulbar function, but not in those with severe bulbar impairment. Adverse effects related to NIV should be systematically reported, as at present there is little information on this subject. More RCT evidence to support the use of NIV in ALS will be difficult to generate, as not offering NIV to the control group is no longer ethically justifiable. Future studies should examine the benefits of early intervention with NIV and establish the most appropriate timing for initiating NIV in order to obtain its maximum benefit. The effect of adding cough augmentation techniques to NIV also needs to be investigated in an RCT. Future studies should examine the health economics of NIV. Access to NIV remains restricted in many parts of the world, including Europe and North America. We need to understand the factors, personal and socioeconomic, that determine access to NIV.

A study on the cough augmentation using a belt-driven assistive

Coughing is one of the most important mechanisms performed in human body in that it removes mucus. The absence of enough ability to remove mucus leads to accumulation of the mucus on the airway, followed by possible complications such as pneumonia and atelectasis. Patients with diseases or disorders such as spinal cord injury have weakened ability in coughing. So far, there have been various treatments such as intubation surgery, mechanical insufflation-exsufflation or manual assistance provided by paramedic. But those treatments are mainly focusing on hospitalized patients. Patients showing better abilities in breathing are rarely and sporadically cared. We found that our prior research to assist breathing of these patients could also assist cough. Also, with our mechanism, now it is available that patients can care about themselves without on by own and more frequently if they needed assistance or treatment. To assist coughing, a belt-driven assistive robot are developed and effectiveness is investigated. With three healthy subjects, general breathing and coughing ability was monitored while using the robot. The result showed about 1.59 times better inhalation and exhalation. Also 1.52 times better coughing ability was measured.

The Effect of Noninvasive Positive Pressure Ventilation on Pneumonia Hospitalizations in Children With Neurological Disease

The aim of this retrospective single-institution observational study was to identify whether the frequency of hospitalizations for pneumonia would change before and after the initiation of noninvasive positive pressure ventilation in children with neurological conditions. Included patients were 1 to 18 years old with an underlying neurological disease and had been prescribed nocturnal noninvasive positive pressure ventilation. The authors excluded patients with a tracheostomy or those who used noninvasive positive pressure ventilation solely for obstructive sleep apnea. A total of 14 patients were included in the study, among whom there was no significant change in the mean number of pneumonias 2 years before versus after the initiation of noninvasive positive pressure ventilation (mean difference = -0.714, standard deviation = 2.4, P = .312). These findings suggest that while noninvasive positive pressure ventilation may not reduce absolute pneumonia frequency, it may have the beneficial value of preventing an increase in the frequency of pneumonias over time, especially in children with progressive respiratory compromise.

Non-invasive ventilation with intelligent volume-assured pressure support versus pressure-controlled ventilation: effects on the respiratory event rate and sleep quality in COPD with chronic hypercapnia

BACKGROUND

COPD patients who develop chronic hypercapnic respiratory failure have a poor prognosis. Treatment of choice, especially the best form of ventilation, is not well known.

OBJECTIVES

This study compared the effects of pressure-controlled (spontaneous timed [ST]) non-invasive ventilation (NIV) and NIV with intelligent volume-assured pressure support (IVAPS) in chronic hypercapnic COPD patients regarding the effects on alveolar ventilation, adverse patient/ventilator interactions and sleep quality.

METHODS

This prospective, single-center, crossover study randomized patients to one night of NIV using ST then one night with the IVAPS function activated, or vice versa. Patients were monitored using polysomnography (PSG) and transcutaneous carbon dioxide pressure (PtcCO2) measurement. Patients rated their subjective experience (total score, 0-45; lower scores indicate better acceptability).

RESULTS

Fourteen patients were included (4 females, age 59.4±8.9 years). The total number of respiratory events was low, and similar under pressure-controlled (5.4±6.7) and IVAPS (8.3±10.2) conditions (P=0.064). There were also no clinically relevant differences in PtcCO2 between pressure-controlled and IVAPS NIV (52.9±6.2 versus 49.1±6.4 mmHg). Respiratory rate was lower under IVAPS overall; between-group differences reached statistical significance during wakefulness and non-rapid eye movement sleep. Ventilation pressures were 2.6 cmH2O higher under IVAPS versus pressure-controlled ventilation, resulting in a 20.1 mL increase in breathing volume. Sleep efficiency was slightly higher under pressure-controlled ventilation versus IVAPS. Respiratory arousals were uncommon (24.4/h [pressure-controlled] versus 25.4/h [IVAPS]). Overall patient assessment scores were similar, although there was a trend toward less discomfort during IVAPS.

CONCLUSION

Our results show that IVAPS NIV allows application of higher nocturnal ventilation pressures versus ST without affecting sleep quality or inducing ventilation- associated events.

Risk of Unsuccessful Noninvasive Ventilation for Acute Respiratory Failure in Heterogeneous Neuromuscular Diseases: A Retrospective Study

If invasive ventilation can be avoided by performing noninvasive mechanical ventilation (NIV) in patients with acute respiratory failure (ARF), the disease can be effectively managed. It is important to clarify the characteristics of patients with neuromuscular diseases in whom initial NIV is likely to be unsuccessful. We studied 27 patients in stable neuromuscular condition who initially received NIV to manage fatal ARF to identify differences in factors immediately before the onset of ARF among patients who receive continuous NIV support, patients who are switched from NIV to invasive ventilation, and patients in whom NIV is discontinued. Endpoints were evaluated 24 and 72 hours after the initiation of NIV. After 24 hours, all but 1 patient with amyotrophic lateral sclerosis (ALS) received continuous NIV support. 72 hours later, 5 patients were switched from NIV to invasive ventilation, and 5 patients continued to receive NIV support. 72 hours after the initiation of NIV, the proportion of patients with a diagnosis of ALS differed significantly among the three groups (P=0.039). NIV may be attempted to manage acute fatal respiratory failure associated with neuromuscular diseases, but clinicians should carefully manage the clinical course in patients with ALS.

Definition, discrimination, diagnosis and treatment of central breathing disturbances during sleep

The complexity of central breathing disturbances during sleep has become increasingly obvious. They present as central sleep apnoeas (CSAs) and hypopnoeas, periodic breathing with apnoeas, or irregular breathing in patients with cardiovascular, other internal or neurological disorders, and can emerge under positive airway pressure treatment or opioid use, or at high altitude. As yet, there is insufficient knowledge on the clinical features, pathophysiological background and consecutive algorithms for stepped-care treatment. Most recently, it has been discussed intensively if CSA in heart failure is a “marker” of disease severity or a “mediator” of disease progression, and if and which type of positive airway pressure therapy is indicated. In addition, disturbances of respiratory drive or the translation of central impulses may result in hypoventilation, associated with cerebral or neuromuscular diseases, or severe diseases of lung or thorax. These statements report the results of an European Respiratory Society Task Force addressing actual diagnostic and therapeutic standards. The statements are based on a systematic review of the literature and a systematic two-step decision process. Although the Task Force does not make recommendations, it describes its current practice of treatment of CSA in heart failure and hypoventilation.

Diaphragm Dysfunction: Diagnostic Approaches and Management Strategies

The diaphragm is the main inspiratory muscle, and its dysfunction can lead to significant adverse clinical consequences. The aim of this review is to provide clinicians with an overview of the main causes of uni- and bi-lateral diaphragm dysfunction, explore the clinical and physiological consequences of the disease on lung function, exercise physiology and sleep and review the available diagnostic tools used in the evaluation of diaphragm function. A particular emphasis is placed on the clinical significance of diaphragm weakness in the intensive care unit setting and the use of ultrasound to evaluate diaphragmatic action.

Prognostic Value of Initial Assessment of Residual Hypoventilation Using Nocturnal Capnography in Mechanically Ventilated Neuromuscular Patients: A 5-Year Follow-up Study

Background

Restrictive respiratory failure is a major cause of morbidity and mortality in neuromuscular diseases (NMD). Home mechanical ventilation (HMV) is used to treat hypoventilation, and its efficiency is mostly assessed by daytime blood gases or nocturnal oxygen saturation monitoring (SpO₂). Non-invasive transcutaneous measure of CO₂ (TcCO₂) allows to directly assess nocturnal hypercapnia and to detect residual hypoventilation with a higher sensitivity than SpO₂. We aimed to compare the prognostic value of nocturnal SpO₂ and TcCO₂ in ventilated adult NMD patients.

Methods

All consecutive capno-oximetries performed between 2010 and 2011 in ventilated adult NMD patients were analyzed retrospectively. Concomitant blood gas analysis and lung function data were collected. Patients on oxygen therapy were excluded. Nocturnal hypoxemia and hypercapnia (using four different definitions) at baseline were compared in their ability to predict mortality and respiratory events requiring ICU admission during follow-up.

Results

Data from 55 patients were analyzed (median age 28 [interquartile range: 25–36.5] years; 71% Duchenne muscular dystrophy; vital capacity 12 [7–27]% of predicted; 51% tracheostomy). Capno-oxymetry showed hypoxemia in 14.5% and hypercapnia in 12.7–41.8%, according to the used definition. Over a follow-up lasting up to 5 years (median 4.0 [3.6–4.5] years), we observed 12 deaths and 20 respiratory events requiring ICU admission. Hypercapnia was significantly associated with the study outcomes, with TcCO₂ > 49 mmHg during ≥10% of the time being the best definition, while hypoxemia was not.

Conclusion

Our data show for the first time that residual hypoventilation, assessed by capnometry, is significantly associated with negative outcomes in adult ventilated NMD patients, while oximetry is not. Accordingly, we suggest capnometry to be included in the systematic assessment of HMV efficiency in NMD patients.

ClinicalTrials.gov Identifier

NCT02551406.

Living and dying with respiratory failure: facilitating decision making

Respiratory failure is a predictable cause of death in end stage lung disease including COPD and neuromuscular disorders, and the symptom burden for these individuals in the last six months of life is significant. Palliative care services are less well-developed for patients with chronic disorders compared to those with malignant disease; and communication problems can be compounded by a mismatch in expectadons between patients and health care providers on prognosis and other issues. Most patients want more information about their illness to facilitate participation in decision making. Noninvasive ventilation may extend life and palliate symptoms in neuromuscular disorders such as Duchenne muscular dystrophy and motor neurone disease/ALS.

Effects of non-invasive ventilation and posture on chest wall volumes and motion in patients with amyotrophic lateral sclerosis: a case series

Background

The effects of non-invasive ventilation (NIV) on the breathing pattern and thoracoabdominal motion of patients with amyotrophic lateral sclerosis (ALS) are unknown.

Objectives

1) To analyze the influence of NIV on chest wall volumes and motion assessed by optoelectronic plethysmography in ALS patients and 2) to compare these parameters in the supine and sitting positions to those of healthy individuals (without NIV).

Method

Nine ALS patients were evaluated in the supine position using NIV. In addition, the ALS patients and nine healthy individuals were evaluated in both sitting and supine positions. Statistical analysis was performed using the paired Student t-test or Wilcoxon test and the Student t-test for independent samples or Mann-Whitney U test.

Results

Chest wall volume increased significantly with NIV, mean volume=0.43 (SD=0.16)L versus 0.57 (SD=0.19)L (p=0.04). No significant changes were observed for the pulmonary rib cage, abdominal rib cage, or abdominal contribution. The index of the shortening velocity of the diaphragmatic muscle, mean=0.15 (SD=0.05)L/s versus 0.21 (SD=0.05)L/s (p<0.01), and abdominal muscles, mean=0.09 (SD=0.02)L/s versus 0.14 (SD=0.06)L/s (p<0.01), increased during NIV. Comparisons between the supine and sitting positions showed similar changes in chest wall motion in both groups. However, the ALS patients presented a significantly lower contribution of the abdomen in the supine position compared with the controls, mean=56 (SD=13) versus 69 (SD=10) (p=0.02).

Conclusions

NIV improved chest wall volumes without changing the contribution of the chest wall compartment in ALS patients. In the supine position, ALS patients had a lower contribution of the abdomen, which may indicate early diaphragmatic dysfunction.

Epidemiology of amyotrophic lateral sclerosis: A review of literature

Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disease of motor neurons, resulting in worsening weakness of voluntary muscles until death occurs from respiratory failure. The incidence of ALS in European populations is two to three people per year per 100,000 of the general population. In Europe, crude prevalences range from 1.1/100,000 population in Yugoslavia to 8.2/100,000 in the Faroe Islands. Major advances have been made in our understanding of the genetic causes of ALS, whereas the contribution of environmental factors has been more difficult to assess and large-scale studies have not yet revealed a replicable, definitive environmental risk factor. The only established risk factors to date are older age, male gender and a family history of ALS. Median survival time from onset to death is usually 3 years from the first appearance of symptoms. Older age and bulbar onset are consistently reported to have poorer outcomes. However, there are conflicting data regarding gender, diagnostic delay and El Escorial criteria. The rate of symptom progression has been revealed to be an independent prognostic factor. Psychosocial factors and impaired cognitive function are negatively related to ALS outcome, while nutritional status and respiratory function are also related to ALS prognosis. The effect of enteral nutrition on survival is still unclear, although noninvasive positive pressure ventilation (NIPPV) has been found to improve survival. These findings have relevant implications for the design of future trials.