Progress of central sleep apnea in children / 国际儿科学杂志

Central sleep apnea(CSA)is a kind of sleep related breathing disorders, characterized by recurrent episodes of reduction or cessation of airflow caused by a temporary decrease or loss of respiratory effort during sleep.Central apnea events occur occasionally during sleep in children, but not enough to diagnose CSA.The prevalence of CSA is much lower than that of obstructive sleep apnea.This review mainly discusses the diagnosis and mechanism of CSA in children and the characteristics of central apnea events in the specific pediatric population.

Apnea central del sueño y respiración periódica / Central Sleep Apnea and Periodic Breathing

La apnea central del sueño es causada por una falla temporal del centro ponto-medular que es el responsable de generar una respiración rítmica. Puede ser un hallazgo fisiológico durante la transición vigilia-sueño o estar presente por múltiples causas. La enfermedad cardiovascular o cerebro-vascular, el síndrome de apneas e hipopneas obstructivas durante el sueño, el uso de opioides y el tratamiento con CPAP son las más frecuentes en la práctica clínica, mientras que en sujetos sanos las apneas centrales se relacionan con la altura durante la exposición recreacional. Este trabajo revisa la fisiopatología de las apneas centrales, su clasificación, las normas para su identificación en los estudios de sueño y un enfoque práctico sobre las opciones terapéuticas disponibles.

Central sleep apnea is caused by a temporary failure of the ponto-medullary center that is responsible for generating rhythmic breathing. It can be a physiological finding during the sleep-wake transition or be present for multiple causes. Cardiovascular or cerebrovascular disease, obstructive sleep apnea/hypopnea syndrome, use of opioids and treatment with CPAP (Continuous Positive Airway Pressure) are the most frequent in clinical practice, while in healthy subjects central apneas are related to high altitude during recreational exposure. This study reviews the physiopathology of central apneas, their classification, the current rules for their identification in sleep studies and a practical approach to the therapeutic options available.

Central Sleep Apnea without Cheyne-Stokes Breathing Following an Acute Cerebral Infarction

Central sleep apnea (CSA) is attributed to medical or neurological conditions including stroke. The association of lesion location and CSA in patients with ischemic stroke has not been well elucidated. A 69-year-old man with a history of hypertension and diabetes mellitus was admitted due to stroke. The brain magnetic resonance imaging showed an acute ischemic stroke in the right ventral thalamus and adjacent hypothalamus. During hospitalization, polysomnography (PSG) was performed because repetitive cessation of respiration during sleep was observed by chance. PSG showed severe CSA; the apnea-hypopnea index (AHI) was 73.5 with a minimum oxygen saturation of 89% and central apnea index (CAI) was 63.0. Two years later, follow-up PSG showed that AHI was 7.2 with a minimum oxygen saturation of 91% and CAI was 1.0. We report the patient with CSA after ischemic stroke with right thalamus and adjacent hypothalamus, which resolved spontaneously with time.

A Case of Continuous Positive Airway Pressure Therapy in a Patient with Central Sleep Apnea and Heart Failure / 수면정신생리

Central sleep apnea (CSA) is a highly prevalent comorbidity in patients with heart failure and may present in 25 to 40 percent of heart failure patients. Continuous positive airway pressure (CPAP) is the primary therapeutic option and effective in treatment of obstructive sleep apnea (OSA). In heart failure patients with CSA, several trials of CPAP showed a number of positive effects in heart failure treatment. A 58-year-old male visited the hospital because of dyspnea and he was diagnosed as heart failure with ischemic heart disease. He underwent coronary angiography and received percutaneous coronary intervention due to stenosis at the middle of left anterior descending coronary artery. However, dyspnea was not completely improved after treatment with percutaneous coronary intervention. The patient also experienced snoring and sleep apnea which worsened with symptom of dyspnea in the recent year. We suspected CSA and the patient underwent polysomnography to confirm whether sleep apnea was present. During the polysomnography, CSA with Cheyne-Stokes respiration (CSR) was observed and apnea-hypopnea index was 45.9/hr. The patient was treated with CPAP. After CPAP treatment, hypoxemia and CSA were resolved and dyspnea was improved with reducing NYHA class. We report a case successfully treated with clinical improvement by presuming CSA in a patient with heart failure.

Síndrome de Ondina, hipoventilación central congénita idiopática / Ondine´s curse or idiopathic congenital central hyperventilation syndrome

El síndrome de hipoventilación central congénito idiopático, también conocido como síndrome de Ondina, es una enfermedad poco común, caracterizada por la ausencia congénita del control central de la respiración y disfunción del sistema nervioso autónomo. Su incidencia se estima en aproximadamente 1 de cada 200 000 nacimientos al año. Es una enfermedad de transmisión autosómica dominante, derivada de una mutación heterocigótica del gen PHOX2B, presente en 90 % de los pacientes, pero su causa fisiopatológica aún no está claramente dilucidada. Presenta una elevada tasa de mortalidad, y una dependencia a la ventilación mecánica durante el sueño de por vida; sin embargo, gracias a una atención multidisciplinar y coordinada, con estrecha vigilancia y apoyo, podría esperarse que los pacientes con ella puedan llevar una vida relativamente normal. Se realiza el reporte de un caso diagnosticado en el departamento de Antioquia (Colombia), lugar con importantes barreras socioeconómicas que limitan el estudio complejo de este tipo de enfermedades de baja prevalencia global.

Idiopathic congenital central hypoventilation syndrome, also known as Ondine´s curse, is a rare disease characterized by congenital absence of the central control of breathing and autonomic nervous system dysfunction. Its incidence is estimated to be one per 200,000 births a year. It is an autosomal dominant disease derived from a heterozygous PHOX2B gene mutation, present in 90 % of patients, but its pathophysiological cause has not been elucidated yet. It has a high mortality rate and a lifelong dependency on a life-support device during sleep. However, it could be expected that a coordinated multidisciplinary care, with close monitoring and support, could help this kind of patients to have a relatively normal life. This is the report of a case diagnosed with this disease in Antioquia, Colombia, a place with significant socio-economic limitations that hinder a complete study of this type of low overall prevalence disease.

Same Heart and Different Sleep : A Brief Review of the Association between Sleep Apnea Syndrome and Heart Failure Based on Two Clinical Cases.

The research in the field of sleep medicine has increased during the whole twentieth century, principally for the involvement of sleep-related disordered breathing (SDB) in cardiovascular disease. If sleep encompasses about a third of one’s life, the reasons are mostly linked to its effects on the cardiovascular and respiratory systems. Sleep is a physiological phenomenon characterized by changes in the human body leading to a state of quiescence of the cardiovascular, respiratory and metabolic systems [1]. The importance of these events becomes more evident if we consider what happens in their absence, that is, during SDB syndromes. These syndromes include habitual snoring, sleep apnea, Cheyne-Stokes breathing syndrome and sleep hypoventilation syndrome [2]. Sleep apnea syndromes are characterized by several apneic events during the night, which consist in absence of the airflow or its reduction by more than 90% lasting more than 10 seconds, with consequent oxyhemoglobin desaturation and arousal [2]. These events provoke microawakening and sleep fragmentation that represent, along with hypoxemia, important harmful triggers on the cardiovascular system. In fact, SDB presents as a highly prevalent comorbidity in patients with heart failure (HF); both diseases are related to each other in a bidirectional way through multiple mechanisms: apneic events raise cardiac afterload, and at the same time impaired cardiac function itself may contribute to the development of sleep apnea. HF is a clinical syndrome characterized by signs or symptoms due to the inability of the heart to provide a normal tissue perfusion: the failing cardiac pump is not able to maintain an adequate output for this task. Typical features of HF are represented by shortness of breath, resting or exertion dyspnea, fatigue, fluid retention leading to pulmonary congestion or ankle swelling, and objective evidence of a structurally or functionally abnormal heart at rest [1,3].

Sleep disordered breathing: OSA, CSA, Pathophysiology and Diagnosis.

Obstructive sleep apnea syndrome (OSAS) is a prevalent disorder that has been reported to occur in 2 to 4% of middle-aged adults. A similar prevalence of OSAS has been reported from India as well. However, this condition is frequently unrecognized and underdiagnosed. Important pathophysiological changes in patients with obstructive sleep apnea (OSA) is an alteration in human upper airway leading to a reduction in cross-sectional area of the upper airway contributing to the easy collapsibility of upper airway during sleep. Other pathophysiological changes in OSA are oxidative stress, systemic inflammation, sympathetic nerve activation, endothelial dysfunction, procoagulant activity, intrathoracic pressure changes and metabolic dysregulation. The gold standard for diagnosis of OSA is full polysomnography.

Respiración periódica y apneas del sueño centrales en pacientes con insuficiencia cardíaca: hallazgos clínicos y fisiológicos

Introducción: los trastornos respiratorios del sueño son frecuentes en la población general y en especial entre los pacientes con insuficiencia cardíaca severa. La ocurrencia de respiración periódica de Cheyne-Stokes con apneas centrales (RPCS-AC) durante el sueño, agrava el pronóstico y aumenta significativamente la mortalidad a corto plazo. El objetivo de este estudio fue determinar la prevalencia de este trastorno y las características clínico-fisiológicas de los pacientes en nuestro medio. Material y método: se estudiaron 35 pacientes con insuficiencia cardíaca, sin respiración periódica en vigilia, a los que se les realizó polisomnografía, ecocardiograma, espirometría, gasometría arterial y evaluación de los resultados funcionales del sueño. Resultados: se diagnosticó RPCS-AC en 13 pacientes (37%). Los pacientes con RPCS-AC tuvieron un sueño significativamente más fragmentado (ID/h = 32,9 ± 19,4 versus 15,8 ± 14,3, p <0,001); más tiempo en sueño superficial (S1-2 = 77,4 ± 20,1% versus 63,0 ± 16,7%, p = 0,029); menos tiempo en sueño paradojal (REM = 9,9 ± 6,3% versus 16,6 ± 9,8%, p = 0,035) y mayor tiempo en hipoxia severa durante el sueño (TA<90% = 28,4 ± 29,0% versus 2,4 ± 4,7%, p = 0,008). No existieron diferencias en la función cardíaca, el ECG, la espirometría, los gases en sangre en vigilia, ni en las repercusiones funcionales del sueño. Conclusiones: la RPCS-AC es un trastorno frecuente en la insuficiencia cardíaca avanzada que determina repercusiones adversas sobre la estructura del sueño y la oxigenación arterial.

Introduction: sleep breathing disorders are common in general population and particularly among patients with severe heart failure. The occurrence of Cheyne Stokes periodic breathing with central apneas (RPCS-AC) during sleep, worsens the prognosis and significantly increases short term mortality. The objective of this study was to determine the prevalence of this disorder and the clinic-physiological features of patients in our hospital. Methods: thirty-five consecutive patients with heart failure, without periodic respiration during wakefulness were studied with polisomnography, echocardiogram, spirometry, arterial blood gases and functional outcomes of sleep. Results: thirteen patients were diagnosed with RPCS-AC (37%). Patients with RPCS-AC had significantly more fragmented sleep (ID)/h = 32,9 ± 19,4 versus 15,8 ± 14,3, p<0,001); more time in superficial sleep (S1-2 = 77,4 ± 20,1% versus 63,0 ± 16,7%, p = 0,029); less time in paradoxical sleep (REM = 9,9 ± 6,3% versus 16,6 ± 9,8%, p = 0,035) and more time in severe hypoxia during sleep (TA<90% = 28,4 ± 29,0% versus 2,4 ± 4,7%, p = 0,008). There were no differences in cardiac function, EGG, spirometry, arterial blood gases during wakefulness, neither in sleep functional outcomes. Conclusions: RPCS-AC is a frequent disorder in advanced heart failure patients, that causes adverse consequences on sleep structure and arterial oxygenation.

Sleep apnea and REM sleep behavior disorder in patients with Chiari malformations / Apnéia do sono e distúrbio do comportamento da fase do sono com REM em pacientes com malformações de Chiari

BACKGROUND: Chiari malformations (CM) may result in the appearance of REM sleep behavior disorder (RBD) and sleep apnea syndrome (SAS) that can be considered markers of brain stem dysfunction. PURPOSE: To evaluate the frequency of RBD and SAS in patients with CM type I and II. METHOD: Were evaluated 103 patients with CM by means of full night polysomnography. Were scoring different sleep stages, frequency of abnormal movements (through video monitoring) and abnormal respiratory events. RESULTS: Of the 103 patients, 36 showed CM type I and 67 CM type II. Episodes of RBD were observed in 23 patients. Abnormal apnea-hypopnea index (AHI) was observed in 65 patients. CONCLUSION: The high rate of RBD suggests that this parassomnia and the increased frequency of central sleep apnea episodes, may be considered as a marker of progressive brain stem dysfunction.

INTRODUÇÃO: Malformações de Chiari (MC) podem gerar o aparecimento de distúrbio comportamental da fase do sono com REM (DCR) e síndrome da apnéia do sono (SAS), sugerindo a ocorrência de disfunção do tronco cerebral. OBJETIVO: Avaliar a freqüência de DCR e SAS em pacientes com MC I ou II. MÉTODO: Utilizou-se a polissonografia de noite inteira para a avaliação de 103 pacientes. Classificaram-se as diferentes fases do sono e analisou-se a freqüência de movimentos anormais (monitorada por vídeo) e de eventos respiratórios anormais. RESULTADOS: Dos 103 pacientes analisados, 36 eram portadores de MC I e 67 de MC II. Episódios de DCR foram observados em 23 pacientes. O índice de apnéia/hipopnéia foi considerado anormal em 65 pacientes. CONCLUSÃO: A alta freqüência de DCR e o aumento da freqüência de episódios de apnéia central do sono podem ser considerados manifestação de disfunção progressiva do tronco cerebral.

Ondine's Curse in a Patient with Right Medullary and Bilateral Cerebellar Infarctions: A Case Report

Failure of automatic control of ventilation (Ondine's curse syndrome) is a rare syndrome that sometimes occurs following localized brainstem dysfunction. In this report, we present a case of a 52-year-old male who was admitted to the hospital with sudden-onset nausea. On examination, no lateralization signs were presented. After one hour, his consciousness was altered and he became apneic. After endotracheal intubation and mechanical ventilation, his mentality improved and he was able to ventilate spontaneously. Cranial magnetic resonance imaging demonstrated acute infarction in both cerebellar inferior aspects involving the right side of the medulla. Eleven hours later, the patient's consciousness altered again. Computed tomography demonstrated newly developed hydrocephalus and emergent craniotomy, and extraventricular drainage were performed. The patient improved in both consciousness and respiratory status but complained of mild ataxia and left arm weakness. We recommend cautious examination and early diagnosis and therapeutic decisions in cases of patients with atypical presentation of stroke.

Paradoxical Upper Airway Obstruction and Central Sleep Apnea Developed After Anterior Cervical Spine Fusion / 결핵및호흡기질환

We report a case of a 48-year-old man with a paradoxic upper airway obstruction and central sleep apnea that developed after an anterior cervical spinal fusion. Nine months before being admitted to this hospital, he was diagnosed with a herniated intervertebral disc between the 5th and 6th cervical spine, and the first operation was carried out. Two months later, a pseudoarthrosis has developed and a second operation, an anterior interbody fusion of the C5 and C6 using autogenous strut bone graft, was performed. After the second operation, he began to complain of snoring, excessive daytime sleepiness, insomnia, and a bizarre sound heard near the upper airway during breathing. Nasopharyngoscope and magnetic resonance imaging disclosed a paradoxical narrowing of the nasopharynx during expiration. On the overnight polysomnography, the apnea index was 8.7/h (central apnea, 7.0/h; obstructive apnea, 1.7/h). Nasal continuous positive airway pressure was applied, but he complained of pressure-intolerance, and laser-assisted uvulopalatoplasty was then performed. Two months after surgery, clinical symptoms as well as the apneas had improved markedly. We suggest that this paradoxic upper airway obstruction might be associated with the anterior cervical spinal surgery even though the mechanism is unclear. This case also emphasizes that an upper airway obstruction can contribute to the development of central sleep apnea.