Tracheotomy and children with spinal muscular atrophy type 1: ethical considerations in the French context

Spinal muscular atrophy (SMA) type 1 is a genetic neuromuscular disease in children that leads to degeneration of spinal cord motor neurons. This sometimes results in severe muscular paralysis requiring mechanical ventilation to sustain the child's life. The onset of SMA type 1, the most severe form of the disease, is during the first year of life. These children become severely paralysed, but retain their intellectual capacity. Ethical concerns arise when mechanical ventilation becomes necessary for survival. When professionals assess the resulting life for the child and family, they sometimes fear it will result in unreasonably excessive care. The aim of this article is to present an analysis of ethical arguments that could support or oppose the provision of invasive ventilation in this population. This examination is particularly relevant as France is one of the few countries performing tracheotomies and mechanical ventilation for this condition.     

Pulmonary hyperinflation and respiratory distress following solvent aspiration in a patient with asthma: expectoration of bronchial casts and clinical improvement with high-frequency chest wall oscillation

An 18-year-old student with a history of asthma accidentally inhaled organic solvent during a class, with immediate cough and dyspnea that worsened over several hours. He presented in severe respiratory distress, with hypoxemia and marked pulmonary hyperinflation. Administration of inhaled bronchodilator was ineffective because of agitation, and the patient could not be positioned for chest physiotherapy to treat presumed widespread mucus plugging. High-frequency chest wall oscillation (HFCWO) in the sitting position initially caused increased distress but was subsequently tolerated when noninvasive positive-pressure ventilation (NPPV) via nasal mask was initiated. Almost immediately, the patient began expectorating bronchial mucus casts, with concomitant clinical improvement. Endotracheal intubation was avoided, and with aggressive pharmacologic treatment for acute severe asthma and continuation of intermittent HFCWO-NPPV, the patient made a full recovery over the next several days. This case suggests that the combination of HFCWO and NPPV may be helpful in the presence of mucus plugging as a complication of acute inhalation injury or acute severe asthma.     

Musculoskeletal complications of neuromuscular disease in children

A wide variety of neuromuscular diseases affect children, including central nervous system disorders such as cerebral palsy and spinal cord injury; motor neuron disorders such as spinal muscular atrophy; peripheral nerve disorders such as Charcot-Marie-Tooth disease; neuromuscular junction disorders such as congenital myasthenia gravis; and muscle fiber disorders such as Duchenne's muscular dystrophy. Although the origins and clinical syndromes vary significantly, outcomes related to musculoskeletal complications are often shared. The most frequently encountered musculoskeletal complications of neuromuscular disorders in children are scoliosis, bony rotational deformities, and hip dysplasia. Management is often challenging to those who work with children who have neuromuscular disorders.     

Effect of thoracic bracing on lung function in children with neuromuscular disease]

Respiratory muscle weakness associated with scoliosis in neuromuscular disease leads to respiratory impairment. Children with scoliosis are usually treated with spinal bracing to delay the progress of disease. We studied the impact of spinal bracing on lung function in these children. METHODS: Retrospective study of patient data from January 1997 to January 2003. Spirometry and measurement of lung volume involved 32 observations, corresponding to 17 children with neuromuscular disease, including 14 with spinal muscular atrophy. Data for children with and without a brace were studied. RESULTS: A total of 72% of the children had severe scoliosis (Cobb score>30 degrees ); 40% wore a Garchois brace. Children without a brace showed a mean vital capacity of 65% of predicted value, with a restrictive syndrome in 44% of observations. Children with a brace showed significantly reduced vital capacity (-4.6%; P<0.001) and forced expiratory volume in 1 s (-4.6%; P=0.002). The reduced vital capacity was lower in children with the Garchois brace: -1% (P=0.02). Severity of scoliosis and measured volumes were not related. CONCLUSION: Spinal bracing in children with neuromusclar disease leads to significant respiratory impairment. Assessment of pulmonary function is necessary when a brace is indicated. The Garchois brace might lead to less impairment of respiratory function.     

Complications after cardiovascular surgery in a case of undiagnosed spinal-bulbar muscular atrophy (Kennedy disease)

Neurodegenerative diseases are often associated with life-threatening declines in respiratory and swallowing mechanisms. We report the case of a 70-year-old man who had postoperative dysphagia and respiratory failure that required reintubation after coronary artery bypass surgery. Impairment of the patient's speech, swallowing, and respiratory mechanisms identified during postoperative clinical and instrumental examinations was suggestive of a neurodegenerative disease. Genetic testing confirmed a diagnosis of spinal-bulbar muscular atrophy (Kennedy disease). This case report aims to highlight increased morbidity in patients with undiagnosed neuromuscular disorders in the critical care setting and the benefits of vigilant postoperative monitoring and multidisciplinary involvement throughout the care of complex patients.     

Respirator use in progressive neuromuscular diseases

A survey was conducted to acquire information on the current pattern of respiratory device usage for patients with progressive neuromuscular diseases. Questionnaires were sent to 240 directors of Muscular Dystrophy Association (MDA) clinics. Of the 132 respondents, 32 (24%) physicians provide no respiratory support systems, 44 (33%) prescribe such systems routinely, and 56 (42%) provide the devices under specialized circumstances. A wide variety of negative and positive pressure ventilators are employed for patients having diseases such as amyotropic lateral sclerosis, Duchenne muscular dystrophy, spinal muscular atrophy. In the MDA clinics responding, 495 patients were found to be receiving some form of assisted ventilation. Of that number, 214 (43%) have permanent tracheostomies. We conclude that ventilators are being supplied to individuals with progressive neuromuscular disorders throughout the USA. However, there appear to be no standardized patient selection process or established protocol for respirator use in such cases.     

Pneumothorax associated with mechanical insufflation-exsufflation and related factors

Impaired cough that results in ineffective airway secretion clearance is an important contributor to pulmonary complications in patients with neuromuscular weakness including spinal cord injury. Mechanical insufflation-exsufflation (MI-E) is a respiratory aid used by patients with weak respiratory muscles to increase cough peak flows and improve cough effectiveness. Relative contraindications to MI-E are said to include susceptibility to pneumothorax, but the association of pneumothorax with MI-E use has never before been described. We report two cases of pneumothorax in patients with respiratory muscle weakness associated with daily use of MI-E: one was a 58-yr-old male with C4 ASIA C tetraplegia, and the other was a 26-yr-old male with Duchenne muscular dystrophy. Both patients also used positive-pressure ventilatory assistance. Although seemingly rare in this patient population, ventilator users also using MI-E who have increasing dyspnea or who require increasing positive inspiratory pressures when using noninvasive ventilation should be evaluated for pneumothorax.     

Respiratory failure in infants due to spinal muscular atrophy with respiratory distress type 1

Background Spinal muscular atrophy with respiratory distress type 1 (SMARD1) is a rare autosomal recessive neuromuscular disease of unknown prevalence characterized by degeneration of anterior horn α-motoneurons and manifesting in the first 6 months of life as life-threatening irreversible diaphragmatic paralysis associated with progressive symmetrical muscular weakness (distal lower limbs mainly involved), muscle atrophy, and peripheral sensory neuropathy.Setting Pediatric intensive care unit of tertiary care hospital.Patients We present two new cases of SMARD1 and report two new mutations in the gene IGHMBP2 which encodes immunoglobulin μ-binding protein 2 on chromosome 11q13.Conclusions SMARD1 is a poor-prognosis disease that should be considered when acute respiratory insufficiency, of suspected neuromuscular or unclear cause, develops during the first 6 months of life. Diaphragmatic paralysis, manifesting as dyspnea and paradoxical respiration, is the most prominent presenting sign and diaphragmatic motility should be investigated early by fluoroscopy or ultrasound. Electromyography and nerve conduction studies revealing peripheral motor and sensory neuropathy then suggest the diagnosis which should be confirmed by genetic analysis.This article is discussed in the editorial available at:     

Adult-onset nemaline myopathy presenting as respiratory failure

Nemaline myopathy is a rare congenital myopathy that generally presents in childhood. We report a case of a 44-year-old man who presented with severe hypoxic hypercapnic respiratory failure as the initial manifestation of nemaline myopathy. After starting noninvasive ventilation, his pulmonary function test results improved substantially, and over the 4 years since diagnosis his respiratory function remained stable. There are few reported cases of respiratory failure in patients with adult-onset nemaline myopathy, and the insidious onset in this case is even more unusual. This case highlights the varied presenting features of adult-onset nemaline myopathy and that noninvasive ventilation improves respiratory function.     

Successful management of severe respiratory failure combining heliox with noninvasive high-frequency percussive ventilation

Heliox has been shown to be beneficial in the management of different obstructive pulmonary disorders. High-frequency percussive ventilation has recently been advocated to treat lung injury in children with reduced lung compliance. We report our experience of combining heliox with noninvasive high-frequency percussive ventilation in a 5-yr-old boy with severe acute respiratory failure resulting from advanced cystic fibrosis lung disease. The dramatic improvement allowed stabilization and withholding of endotracheal intubation. We hypothesize that this approach improved gas exchange by enhancing molecular diffusion and by favoring laminar flow throughout the upper and lower airways. Further investigations should study the mechanisms of this noninvasive bimodal therapy.     

Alternatives to endotracheal intubation for patients with neuromuscular diseases

OBJECTIVE: To evaluate the usefulness of continuous noninvasive mechanical ventilation and mechanical coughing aids to avoid endotracheal intubation and tracheostomy during episodes of acute respiratory failure in patients with neuromuscular disease. DESIGN: We conducted a prospective cohort study at the respiratory medicine ward of a university hospital to study the success rate of the use of continuous noninvasive mechanical ventilation and manually and mechanically (CoughAssist) assisted coughing to avert endotracheal intubation in 24 consecutive episodes of acute respiratory failure for 17 patients with neuromuscular disease. The noninvasive mechanical ventilation and coughing aids were used to reverse decreases in oxyhemoglobin saturation and relieve respiratory distress that occurred despite oxygen therapy and appropriate medication. Noninvasive mechanical ventilation was delivered by volume ventilators (Breas PV 501) alternating nasal/oronasal and oral interfaces. RESULTS: Noninvasive management was successful in averting death and endotracheal intubation in 79.2% of the acute episodes. There were no significant differences in respiratory function between the successfully treated and unsuccessfully treated groups before the current episode. Bulbar dysfunction was the independent risk factor for failure of noninvasive treatment (P < 0.05; odds ratio, 35.99%; 95% confidence interval, 1.71-757.68). CONCLUSIONS: Intubation can be avoided for some patients with neuromuscular disease in acute respiratory failure by some combination of noninvasive mechanical ventilation and mechanically assisted coughing. Severe bulbar involvement can limit the effectiveness of noninvasive management.     

Management of airway clearance in neuromuscular disease

The clearance of airway secretions from the lungs is normally supported by the mucociliary escalator and by cough. These protective mechanisms provide an effective means of pulmonary-hygiene maintenance in healthy individuals. Patients with neuromuscular disease that affects the respiratory pump (the muscles of breathing) can experience mild to profound limitation in both ventilation and cough. Neuromuscular respiratory insufficiency, when left untreated, can substantially impact quality of life and life expectancy. In most cases of neuromuscular disease, respiratory failure and pneumonia are the primary causes of death. Invasive mechanical ventilation and tracheal suctioning have been successfully used when needed to support respiratory insufficiency in this population. These modalities, though supportive, have been associated with substantial morbidity when used in patients with neuromuscular disease. The advent of noninvasive ventilation as a means of supporting chronic neuromuscular respiratory insufficiency has spurred the development of noninvasive cough-augmentation therapy to support airway clearance. Unfortunately, the need to support cough clearance is not always addressed, and few guidelines for the management of cough insufficiency have existed until relatively recently. An understanding of neuromuscular respiratory pathophysiology and the modes of effective noninvasive cough support are key in the evaluation and management of neuromuscular diseases. This review is meant to provide a basic understanding of cough mechanics, and the pathophysiology and management of neuromuscular cough insufficiency.     

Duchenne muscular dystrophy: prolongation of life by noninvasive ventilation and mechanically assisted coughing

OBJECTIVE: To quantitate prolongation of survival for patients with Duchenne muscular dystrophy with the use of noninvasive intermittent positive-pressure ventilation (IPPV) with and without access to a protocol involving mechanically assisted coughing. DESIGN: In this retrospective review of all patients with Duchenne muscular dystrophy visiting a neuromuscular disease clinic, patients were trained to use mouth piece and nasal IPPV and mechanically assisted coughing to maintain oxyhemoglobin saturation >94% (protocol). Survival was considered prolonged when noninvasive IPPV was required full time. RESULTS: Ninety-one of 125 patients used noninvasive IPPV part time for 1.9 +/- 1.3 yr, and 51 went on to require it full time for 6.3 +/- 4.6 yr. Of the 31 noninvasive IPPV users who died without access to the protocol, 20 died from respiratory causes and seven died from cardiac causes. None of the 34 full-time noninvasive IPPV users with access to the protocol underwent tracheotomy or died from respiratory complications during a period of 5.4 +/- 4.0 yr, whereas three died from heart failure. Five patients with no breathing tolerance were extubated or decannulated to continuous noninvasive IPPV. CONCLUSIONS: Noninvasive respiratory aids can prolong survival and permit extubation or decannulation of patients with Duchenne muscular dystrophy with no breathing tolerance.     

Successful pregnancy in a patient with spinal muscular atrophy and severe kyphoscoliosis

Pregnancy imposes a load on the respiratory system that is usually easily assumed because of alterations in the thoracoabdominal architecture. It is presumed that the respiratory mechanical disadvantage of severe kyphoscoliosis and the muscle weakness of spinal muscular atrophy impede these adaptations sufficiently to preclude a successful gestation. We report the case of a successful pregnancy in a woman with spinal muscular atrophy, severe uncorrected scoliosis, and the lowest spirometric values reported in the literature without the use of ventilatory support. This patient demonstrates that women with severe kyphoscoliosis and a profound ventilatory limitation can carry a successful pregnancy well into the third trimester without requiring full ventilatory support.     

Intraoperative use of noninvasive ventilation during spinal anaesthesia in patients with severe chronic obstructive pulmonary disease undergoing orthopaedic surgery: A case report

Compared with invasive mechanical ventilation, noninvasive ventilation (NIV) improves patient comfort and neurocognitive function; and reduces the likelihood of nosocomial infections and the need for sedation. NIV can also be used perioperatively to prevent postoperative pulmonary complications. This current report describes a case of a 64-year-old female patient with chronic obstructive pulmonary disease and chronic respiratory failure that underwent spinal anaesthesia during surgery. She was sedated with propofol. She brought her home ventilator equipment to the operating room and it was used in biphasic-positive airway pressure mode for immediate treatment of respiratory depression.     

急诊应用BiPAP呼吸机治疗AECOPD合并Ⅱ型呼吸衰竭的临床分析

目的 探讨在急诊中应用双水平正压通气（BiPAP）呼吸机治疗慢性阻塞性肺疾病加重期（AECOPD）合并Ⅱ型呼吸衰竭患者的临床疗效.方法 52例AECOPD合并Ⅱ型呼吸衰竭的患者随机分成常规治疗组和常规治疗加BiPAP组.对照组（26例）给予常规抗感染,通畅气道,持续低流量吸氧及应用呼吸兴奋剂等治疗.试验组（26例）则在常规治疗基础上予BiPAP无创通气治疗.结果 经BiPAP呼吸机治疗组的临床症状改善和血气分析指标、肺功能恢复正常,与常规治疗的对照组比较差异有统计学意义（P〈0.05）.结论 急诊中应用BiPAP呼吸机治疗AECOPD合并Ⅱ型呼吸衰竭可以明显缓解临床症状,提高动脉血气分析及肺功能.试验组较对照组pH、PaO2、PaCO2、肺功能第一秒用力呼气容积（FEV1）、用力肺活量（FVC）、第一秒用力呼气容积/用力肺活量（FEV1/FVC）和第一秒用力呼气容积占预计值百分比（FEV1%）等明显改善,是一种有效手段.     

Symptoms, clinical and physiological findings motivating home mechanical ventilation in patients with neuromuscular diseases.

OBJECTIVE: To clarify the relationship between symptoms, clinical signs and physiological abnormalities that were motivating the initiation of home mechanical ventilation in patients suffering from neuromuscular diseases. METHODS: From The Swedish Home Mechanical Ventilation Register we identified 352 patients with neuromuscular diseases and we looked at circumstances (acute vs elective) and clinical motives for starting ventilatory support. RESULTS: Home mechanical ventilation was commenced electively in 268 patients (76%) and among these daytime sleepiness was the most common motive, being reported in 56% of the patients. In the 24 children with spinal muscular atrophy, however, 96% started ventilation electively and cough insufficiency was the most common motive. The patients were moderately hypercapnic (PaCO(2): 7.0 kPa, SD 1.3). None of the clinical motives were related to the PaCO(2) level. Average PaO(2) was above 8 kPa in all groups, but lowest in the patients with post-polio and dystrophia myotonica. Mean vital capacity was close to 40% of predicted, but significantly lower in the Duchenne patients (26% of predicted). CONCLUSION: Daytime sleepiness was the most common clinical symptom motivating home mechanical ventilation in this group of patients with chronic hypercapnic respiratory insufficiency secondary to neuro/myopathies. Respiratory function testing is therefore suggested to be included in the diagnostic work up of daytime sleepiness in these patients.     

Successful treatment of acute respiratory distress syndrome and severe pulmonary hypertension in a child with Bordetella pertussis infection

Infection with Bordetella pertussis can cause severe illness with neurological and pulmonary complications in children. Pulmonary hypertension is an early sign of potentially fatal disease and can cause failure of conventional respiratory therapy in severe acute respiratory distress syndrome (ARDS). We report a 4 1/2-year-old boy with B. pertussis infection who developed severe ARDS and pulmonary hypertension. Because of severe neurological signs the patient did not qualify for extracorporal membrane oxygenation (ECMO). After conventional ventilation, surfactant and high frequency oscillation ventilation (HFOV) failed, treatment with nitric oxide (NO) improved oxygenation, allowing recovery without the need for ECMO. The patient survived with few sequelae. Thus, this treatment may be an option in high-risk children who meet the criteria for ECMO but are excluded because of poor neurological status, as in our patient.     

Intrapulmonary percussive ventilation improves the outcome of patients with acute exacerbation of chronic obstructive pulmonary disease using a helmet

OBJECTIVE: To evaluate the effect of intrapulmonary percussive ventilation (IPV) by mouthpiece during noninvasive positive-pressure ventilation with helmet in patients with exacerbation of chronic obstructive pulmonary disease (COPD). DESIGN: Randomized clinical trial. SETTING: General intensive care unit, university hospital. PATIENTS: Forty patients with exacerbation of COPD ventilated with noninvasive positive-pressure ventilation by helmet were randomized to two different mucus clearance strategies: IPV (IPV group) vs. respiratory physiotherapy (Phys group). As historical control group, 40 patients receiving noninvasive positive pressure and ventilated by face mask treated with respiratory physiotherapy were studied. INTERVENTIONS: Two daily sessions of IPV (IPV group) or conventional respiratory physiotherapy (Phys group). MEASUREMENTS AND MAIN RESULTS: Physiologic variables were measured at entry in the intensive care unit, before and after the first session of IPV, and at discharge from the intensive care unit. Outcome variables (need for intubation, ventilatory assistance, length of intensive care unit stay, and complications) were also measured. All physiologic variables improved after IPV. At discharge from the intensive care unit, Paco2 was lower in the IPV group compared with the Phys and control groups (mean +/- sd, 58 +/- 5.4 vs. 64 +/- 5.2 mm Hg, 67.4 +/- 4.2 mm Hg, p < .01). Pao2/Fio2 was higher in IPV (274 +/- 15) than the other groups (Phys, 218 +/- 34; control, 237 +/- 20; p < .01). In the IPV group, time of noninvasive ventilation (hrs) (median, 25th-75th percentile: 61, 60-71) and length of stay in the intensive care unit (days) (7, 6-8) were lower than other groups (Phys, 89, 82-96; control, 87, 75-91; p < .01; and Phys, 9, 8-9; control, 10, 9-11; p < .01). CONCLUSIONS: IPV treatment was feasible for all patients. Noninvasive positive-pressure ventilation by helmet associated with IPV reduces the duration of ventilatory treatment and intensive care unit stay and improves gas exchange at discharge from intensive care unit in patients with severe exacerbation of COPD.     

Respiratory issues in the management of children with neuromuscular disease

Most children with neuromuscular disease eventually require assistance with airway clearance and with breathing, especially during sleep. Techniques and devices for airway clearance and noninvasive ventilation that are commonly used in adults have been successfully adapted for use in infants and young children. Both physiological differences and small size of young patients with neuromuscular disease, however, can limit the applicability of such interventions or require special consideration. Measurements to identify the appropriate time to begin airway clearance assistance are lacking for young children, and the role of early introduction of noninvasive ventilation to preserve or enhance lung growth and chest-wall mobility remains to be elucidated. The paucity of nasal interfaces and headgear commercially made for small patients can reduce patient tolerance of noninvasive ventilation and exacerbate patient-ventilator dyssynchrony. Despite these issues, a greater number of children with neuromuscular diseases are living well past their second decade. Strategies to transition these patients to appropriate adult-care providers, to secure cost-effective health care for them, and to help integrate them into adult society must be developed.