Sleep-disordered Breathing in Neuromuscular Disease.

Sleep-disordered breathing in neuromuscular diseases is due to an exaggerated reduction in lung volumes during supine sleep, a compromised physiologic adaptation to sleep, and specific features of the diseases that may promote upper airway collapse or heart failure. The normal decrease in the rib cage contribution to the tidal volume during phasic REM sleep becomes a critical vulnerability, resulting in saw-tooth oxygen desaturation possibly representing the earliest manifestation of respiratory muscle weakness. Hypoventilation can occur in REM sleep and progress into non-REM sleep, with continuous desaturation and hypercarbia. Specific characteristics of neuromuscular disorders, such as pharyngeal neuropathy or weakness, macroglossia, bulbar manifestations, or low lung volumes, predispose patients to the development of obstructive events. Central sleep-disordered breathing can occur with associated cardiomyopathy (e.g., dystrophies) or from instability in the control of breathing due to diaphragm weakness. Mitigating factors such as recruitment of accessory respiratory muscles, reduction in REM sleep, and loss of normal REM atonia in some individuals may partially protect against sleep-disordered breathing. Noninvasive ventilation, a standard-of-care management option for sleep-disordered breathing, can itself trigger specific sleep-disordered breathing events including air leaks, patient-ventilator asynchrony, central sleep apnea, and glottic closure. These events increase arousals, reduce adherence, and impair sleep architecture. Polysomnography plays an important role in addressing pitfalls in the diagnosis of sleep-disordered breathing in neuromuscular diseases, identifying sleep-disordered breathing triggered by noninvasive ventilation, and optimizing noninvasive ventilation settings.

Case report of os odontoideum causing Ondine's curse.

Ondine's curse or central hypoventilation syndrome is most common congenital disorder which is diagnosed in infancy. In the majority of cases, no structural abnormality is identified. We describe the case of an 18-year-old patient who presented with Ondine's curse secondary to an os odontoideum.

Reversible Central Hypoventilation Syndrome in Basilar Invagination.

BACKGROUND: A noninvasive approach for basilar invagination (BI) and moreover, cervical traction to reduce odontoid invagination, has not been thoroughly described in the literature. We report a case of BI with Arnold-Chiari malformation in which preoperative reduction using Gardner well cervical traction was attempted and the patient developed central hypoventilation syndrome. CASE DESCRIPTION: A 15-year-old boy presented with a 6-month history of progressive cervical myelopathy signs and symptoms, modified Japanese orthopedic association score 12 of 18. Radiology showed type A BI with occipitalization of atlas and a posterior arch defect of axis. A preoperative closed cervical traction followed by occipitocervical fusion via a posterior-only approach was planned. The patient developed 3 episodes of apnea on sleeping when on traction. Labeled as central hypoventilation, he was operated by foramen magnum decompression and occipitocervical fusion. CONCLUSIONS: Cervical traction followed by posterior fixation is an effective way to manage basilar invagination with Arnold-Chiari malformation and assimilated C1. However, patients should be monitored closely for respiratory dysfunction.

[Central apnea developing during treatment with a mandibular advancement device]. / Apnées centrales induites sous traitement par orthèse d'avancée mandibulaire.

INTRODUCTION: Mandibular advancement (MA) has emerged over the last decade as an alternative solution to nasal continuous airway pressure (nCPAP) for the treatment of obstructive sleep apnea syndrome (OSAS). OBSERVATION: We report the case of a patient with history of chronic atrial fibrillation and moderate supine-dependent OSAS in whom central sleep apneas developed during treatment by a bi-bloc MA device. Central apneas increased with the level of MA and preferentially occurred in the supine position. We hypothesized that mouth opening under excessive mandibular advancement in supine position may have led to pharyngeal narrowing at the base of the tongue and potentially unstable ventilation. Sleep fragmentation that enhanced during progressive MA may also have compromised ventilatory control stability in our patient. Finally, chronic atrial fibrillation may have predisposed to central sleep apneas. CONCLUSION: Our case report highlights the importance of follow-up nocturnal recordings during progressive MA.

Mandibular Advancement Device-Emergent Central Sleep Apnea Can Resolve Spontaneously: A Case Report.

ABSTRACT: The development of treatment emergent central sleep apnea (CSA) has been described after almost all obstructive sleep apnea (OSA) therapies. While the course of positive airway pressure (PAP) emergent CSA, is better established; little is known about the natural course of mandibular advancement device (MAD) emergent CSA. Previous reports failed to comment on its natural course or report treatment with advanced ventilator modes such as adaptive servoventilation. We describe spontaneous resolution of MAD emergent CSA in a patient with moderate OSA who refused PAP. We also highlight the need for follow up polysomnography (PSG) after maximal advancement with a MAD and the possible association between MAD emergent CSA and atrial fibrillation. The exact pathophysiology of this phenomenon remains unclear but may relate to high loop gain of the respiratory system resulting in ventilatory overshoot after treatment and atrial fibrillation associated increased susceptibility to periodic ventilation.

The emergence of central sleep apnea after surgical relief of nasal obstruction in obstructive sleep apnea.

By the current definition, complex sleep apnea (CompSA) refers to the emergence of central sleep apnea (CSA) during the treatment of obstructive sleep apnea (OSA) with continuous positive airway pressure (CPAP). However, new-onset CSA has been described with use of other treatments for OSA, including tracheostomy, maxillofacial surgery, and mandibular advancement device. We present a patient with CSA beginning after endoscopic sinus and nasal surgery for nasal obstruction in the setting of mild OSA. This case highlights the importance of non-PAP mechanisms in the pathogenesis of CompSA.

Development of central sleep apnea after maxillofacial surgery for obstructive sleep apnea.

Central sleep apnea is a rarely reported complication of surgery for obstructive sleep apnea (OSA). We report the case of a 38-year-old male who developed marked central sleep apnea 3 months after a maxillomandibular advancement for moderate OSA, which spontaneously resolved on his 6-month postoperative polysomnogram. Five prior cases of this postoperative complication have been reported in nonobese individuals after tracheostomy for OSA. Additionally, a recent study demonstrated that patients with atmospheric pharyngeal closing pressures are susceptible to unstable ventilation. We hypothesize that latent high loop gain from chronic OSA, coupled with atmospheric pharyngeal closing pressures, predisposed our patient to develop unstable ventilation after an abrupt postoperative change in his ventilatory load. Our case supports delaying postoperative polysomnography > or = 6 months in individuals at high risk for this complication.

Paroxysmal extreme pain disorder (previously familial rectal pain syndrome).

OBJECTIVE: To describe the clinical phenotype of paroxysmal extreme pain disorder (previously called familial rectal pain syndrome), an autosomal dominant condition recently shown to be a sodium channelopathy involving SCN9A. METHODS: An international consortium of clinicians, scientists, and affected families was formed. Clinical details of all accessible families worldwide were collected, including age at onset, features of attacks, problems between attacks, investigational results, treatments tried, and evolution over time. A validated pain questionnaire was completed by 14 affected individuals. RESULTS: Seventy-seven individuals from 15 families were identified. The onset of the disorder is in the neonatal period or infancy and persists throughout life. Autonomic manifestations predominate initially, with skin flushing in all and harlequin color change and tonic attacks in most. Dramatic syncopes with bradycardia and sometimes asystole are common. Later, the disorder is characterized by attacks of excruciating deep burning pain often in the rectal, ocular, or jaw areas, but also diffuse. Attacks are triggered by factors such as defecation, cold wind, eating, and emotion. Carbamazepine is effective in almost all who try it, but the response is often incomplete. CONCLUSIONS: Paroxysmal extreme pain disorder is a highly distinctive sodium channelopathy with incompletely carbamazepine-sensitive bouts of pain and sympathetic nervous system dysfunction. It is most likely to be misdiagnosed as epilepsy and, particularly in infancy, as hyperekplexia and reflex anoxic seizures.

Sleep disturbances in 22q11.2 deletion syndrome: a case with obstructive and central sleep apnea.

The 22q11.2 deletion syndrome is characterized by wide phenotypic variability, frequently involving characteristic craniofacial features, cardiac malformations, and learning difficulties. Skeletal anomalies are also common and include an obtuse angle of the cranial base, retrognathia, and cervical spine abnormalities. Despite these anomalies, sleep-disturbed breathing is not reported frequently in patients with 22q11.2 deletion syndrome. We describe a patient with an obstructive sleep disturbance that was successfully treated with a tonsillectomy followed by mandibular distraction osteogenesis. She also had central sleep apnea, initially attributed to spinal cord impingement from cervical instability. Posterior cervical fusion was associated with a decrease in the number of central apneic events.