Association between the severity of chronic spontaneous urticaria and sleep-disordered breathing

BACKGROUND

Chronic spontaneous urticaria (CSU) is a common mast cell-driven disease, presenting with wheals, angioedema, or both. Sleep-disordered breathing (SDB) is also a common condition and contributes to various diseases by causing chronic inflammation. Recent studies have suggested an association between CSU and SDB.

METHODS

To determine the association between the severity of SDB and that of CSU, we studied consecutive patients with CSU who visited the Sagamihara National Hospital allergy department or dermatology department between April 1 and October 31, 2018. The severity of CSU and SDB was evaluated based on the urticaria activity score 7 (UAS7) and peripheral arterial tone apnea-hypopnea index (pAHI) derived from out-of-center sleep testing (OCST) findings, respectively; their correlation was examined.

RESULTS

Of the 37 patients studied, 19 had symptom-free-to-mild CSU (UAS7 ≤15) and 18 had moderate-to-severe CSU (UAS7 ≥16). The pAHI in the latter group was significantly higher than that in the former group (18 vs. 4.2, p = 0.001). In multivariate logistic analysis, moderate-to-severe SDB (pAHI ≥15) was significantly associated with moderate-to-severe CSU even after adjusting for the BMI (adjusted odds ratio 22 [95% confidence interval, 1.7-285]).

CONCLUSIONS

The severity of SDB is correlated with that of CSU independently of the BMI. Physicians should consider comorbid SDB when treating patients with CSU.

Anesthetic care for the child with congenital central alveolar hypoventilation syndrome (Ondine's curse)

Idiopathic congenital central alveolar hypoventilation syndrome, otherwise known as Ondine's curse, is a rare neuropathologic syndrome characterized by an inadequate respiratory drive with hypoventilation and periods of prolonged apnea resulting in hypercarbia and hypoxemia. Although no definite pathologic abnormality has been identified to account for the disorder, it is thought to represent a primary defect related to altered function of central chemoreceptors resulting in defective control of minute ventilation. Associated problems related to neural crest cell migration, including neuroblastoma formation and Hirschsprung's disease, suggest that the primary defect is defective neural crest cell migration and function. Problems that may impact on perioperative care include the defective central control of ventilation and defective control of upper respiratory musculature, which may lead to upper airway obstruction. Although many patients will have previously undergone tracheostomy and chronic mechanical ventilation, problems in other organ systems can impact on perioperative care. Cardiovascular issues include the possible presence of cor pulmonale and autonomic nervous system dysfunction. Central nervous system issues include the frequent occurrence of seizures and mental retardation. The preoperative work-up, premedication, and the intraoperative/postoperative care and monitoring of these patients is reviewed.

Resolution of obstructive sleep apnea syndrome after adenoidectomy in congenital central hypoventilation syndrome

We report on a 2 1/2-year-old boy who is currently ventilated at home by positive pressure ventilation through a nasal mask during the night because of congenital central hypoventilation syndrome (CCHS). Up to age 2 he had developed normally. A reevaluation was performed because of symptoms suggestive of obstructive sleep apnea syndrome (OSAS), including snoring, nocturnal sweating, frequent nighttime awakenings, speech impairment, daytime fatigue, and failure to thrive. A sleep study indicated obstructive apnea episodes lasting up to 40 s and arterial desaturations below 50% during spontaneous sleep. During mechanical ventilation snoring persisted, and capillary PCO2 rose to 60 mm Hg. Partial upper airway obstruction, leaking around the mask, and arousal movements developed on passive flexion of the neck to 20 degrees. After adenoidectomy, symptoms of OSAS resolved. There were no more obstructive apneas during spontaneous sleep, but obstructive apneas could be provoked by neck flexion to 20 degrees. During ventilation, neck flexion of 20 degrees was tolerated, but a 40 degrees flexion led to partial obstruction. In CCHS patients, the problem of upper airway obstruction is rarely noted because most patients are ventilated through a permanent tracheostomy. Today, noninvasive ventilation strategies are becoming more common. Reduced activity of upper airway muscles and impaired reflex mechanisms could lead to upper airway obstruction during face mask positive pressure ventilation in children with CCHS. Enlarged adenoids worsened this problem in our patient, leading to insufficient ventilation and OSAS. Adenoidectomy resolved symptoms of OSAS and enabled successful nasal mask ventilation. Close follow-up of the patient avoided hypoxia and sequelae from OSAS such as pulmonary hypertension.

[From tracheostomy to non-invasive mask ventilation: a study in children with congenital central hypoventilation syndrome]

BACKGROUND

Children with congenital central hypoventilation syndrome (CCHS) have to be ventilated during sleep due to respiratory insensitivity to CO2. This long-term mechanical ventilation sometimes requires a tracheostomy during infancy, leading to increased risk of infections and of tracheal problems, and later on to stigmatization and restrictions in social life.

PATIENTS AND METHOD

We therefore evaluated non-invasive mask ventilation in 4 children between 6 and 15 years of age, who had been ventilated via tracheal canula since early infancy under polysomnographic control.

RESULTS

Best results were obtained with standard face masks in connection with pressure controlled timed ventilation. In 1 child we used a volume-controlled ventilator. The lack of dyspnea in these patients can worsen the acceptance of a face mask, which is more uncomfortable than a tracheal cannula. In 2 children we waited with the definite closure of the tracheostomy due to pavor-like symptoms and laryngeal closure during sleep and problems in acceptance of the mask, respectively. In the other 2 children we could demonstrate effective non-invasive mask ventilation during temporary tracheal closure for several nights. Therefore the tracheostomy was definitely closed. Long-term follow-up with home monitoring showed effectiveness of non-invasive ventilation in these cases.

[Sleep-phase-related home therapy in congenital central hypoventilation syndrome (CCHS)]

PATIENTS AND METHOD

Eight children with congenital central hypoventilation syndrome (CCHS) (aged 3 to 16 years) underwent repeated polysomnographic recordings (sleep-EEG, induction plethysmography, PtcO2, PtcCO2, PACO2, FO2, SaO2, ECG) during spontaneous breathing and during therapy. The result led to individual therapeutic plans.

RESULT

During NREM sleep a close relationship between increasing EEG-delta-activity and increasing PCO2 could be observed (PCO2 max. 107 mm Hg in NREM IV). A similar effect was seen during mechanical ventilation with decreasing spontaneous respiratory activity during increasing sleep depth (PCO2 max. 89 mm Hg in NREM IV). Associated with NREM I/II and REM sleep strong variations in spontaneous breathing with consecutive variations of blood gases were observed. Hyperventilation during REM sleep (PCO2 min. 20 mm Hg) could occur with continuous mechanical ventilation. A continuous blood gas monitoring improved home therapy since blood gas adapted control of mechanical ventilation was possible now. This caused a stabilization of blood gases in sleep.

CONCLUSION

Patients with CCHS show a vigilance-dependent, enlarged variability of blood gases which should be considered in the management of home therapy. Continuous monitoring and blood gas adapted mechanical ventilation obtain a stabilization of acid-base balance during sleep. Preliminary data suggest a positive effect on sleep-wake quality and mental performance.

Association of misoprostol, Moebius syndrome and congenital central alveolar hypoventilation. Case report

We report a case showing the association of Moebius syndrome, the use of misoprostol during pregnancy and the development of central congenital alveolar hypoventilation. Pathophysiological aspects of these three diseases are discussed and also the unfavorable prognosis of this association.

Respiratory sensations during heavy exercise in subjects without respiratory chemosensitivity

Breathlessness arises from increased medullary respiratory center activity projecting to the forebrain (respiratory corollary discharge hypothesis). Subjects with congenital central hypoventilation syndrome (CCHS) lack the normal hyperpnea and breathlessness during hypercapnia. The corollary discharge hypothesis predicts that if CCHS subjects have normal hyperpnea during exercise, they will experience normal breathlessness during exercise. To test this, we studied four CCHS subjects and six matched controls during an exhausting constant-load cycling test requiring substantial anaerobiosis. CCHS subjects rated significantly less breathlessness at the end of the test than controls, but ventilation (index of respiratory corollary discharge) was also somewhat lower in CCHS (not significant). In both groups, breathlessness increased disproportionately more than ventilation towards the end of exercise. These data failed to disprove the corollary discharge hypothesis of breathlessness, but do suggest that the relationship between ventilation and breathlessness is non-linear and/or that projections of chemoreceptor afferents to the forebrain (presumed lacking in CCHS) is one source of breathlessness in normals.

Congenital central hypoventilation syndrome: an update

Awareness of the existence of CCHS has led to increasingly frequent reports of such patients from all over the world. However, the exact pathophysiologic mechanisms underlying the clinical manifestations of this congenital disease entity remain unknown. For the respiratory physiologist, CCHS can be viewed as an experiment of nature that provides an important and unique window into central cardiorespiratory regulation. For the pediatrician, CCHS children represent an unique clinical challenge in coordinating the diagnostic and therapeutic procedures required to enhance the patients' quality of life.

[Home mechanical ventilation with nasal intermittent positive pressure ventilation for a boy with congenital central hypoventilation syndrome]

We report a 4-year-old boy with congenital central hypoventilation syndrome (CCHS) successfully treated with home mechanical ventilation with nasal intermittent positive pressure ventilation (NIPPV) during sleep hours. He had had frequent severe apneic attacks from the neonatal period. At 8 months, he was treated with positive pressure ventilation following a tracheostomy. At 4 year and 2 months, NIPPV was attempted because of recurrent respiratory tract infections and cor pulmonale. The tracheostomy was successfully abandoned 6 months later. Adequate ventilation has been maintained for more than 3 years without troubles. NIPPV is an effective and non-invasive treatment of CCHS that it significantly improves the quality of life during daytime.

[Obstructive sleep apnea in the child: an interdisciplinary treatment concept with special reference to craniofacial changes]

Diagnosis and therapy of obstructive sleep-related breathing disturbances SRBD in adults may not be applied without hesitation to children. SRBD in newborn and infants are often due to craniofacial disturbances (Pierre Robin syndrome, Goldenhars syndrome etc.), obesity is of minor importance. More than 30 infants with SRBD and craniofacial changes have been diagnosed and successfully treated over a 2-year period. Conservative therapy starts immediately after birth. The first step in newborn with Pierre Robin syndrome, for instance, is prone position for protrusion of tongue and mandible and mandibular growth stimulation. Intermediate nightly nasopharyngeal tubes are an alternative to nCPAP-/BiPAP treatment. Conventional orthopaedic/orthodontic treatment should not be neglected, even if it takes years to become effective. Surgical therapies are able to support, sometimes to replace or at least to shorten conservative methods. In rare cases when prone position in combination with palatal plates in cases of Robin syndrome, for instance, are not fully effective, mandibular extension is indicated. Aplasia or defects demand adequate surgical reconstruction, even if this does not necessarily mean abolishment of SRBD. In contrast to adults adenotonsillectomy is highly effective in infants and does not only reduce SRBD, but also improves nasal breathing and thus positively influences facial growth. A relatively new method is gradual mandibular distraction osteogenesis according to Ilizarov, which also enhances soft tissue growth. Maxillary and mandibular advancement osteotomies should not be considered before the termination of facial growth. Thanks to this refined treatment concept we were able to avoid tracheotomies in children during the past few years.

Pediatric hypoventilation syndromes

Hypoventilation syndromes are an uncommon but important group of respiratory control disorders in infants and children. Congenital central hypoventilation syndrome (CCHS) is the principal and most important example. No specific anatomical or biochemical mechanism has yet been identified. This article summarizes current knowledge regarding CCHS in infants and children, and emphasizes the most recent and most important publications. The most recent advances in CCHS pertain to its genetics, pathophysiology, diagnosis, and treatment and provide state-of-the-art information regarding advances in diaphragm pacing, responses to exercise, and long-term outcome. CCHS is now being recognized more frequently, treatment is more successful, and long-term outcomes are encouraging with timely diagnosis, state-of-the-art treatment, and comprehensive follow-up at an experienced pediatric referral center.

Peripheral chemoreceptors in congenital central hypoventilation syndrome

Congenital central hypoventilation syndrome (CCHS) is a rare disorder of unknown etiology, characterized by failure of the autonomic control of respiration. The primary defect is believed to involve central respiratory control; however, no specific lesion has been identified. We report two cases of CCHS (one female, 3 mo of age and one male 2 yr of age) in which there was detailed examination of the neural, muscular, and chemoreceptor components of respiratory control. Although no specific abnormalities were identified in the central nervous system (CNS) or muscles of respiration, striking changes were observed in arterial chemoreceptors, carotid bodies (CB), and airway chemoreceptors, neuroepithelial bodies (NEB). In both cases, CB were small (< 50% of control), with a marked decrease in the number of glomus cells identified by immunostaining for tyrosine hydroxylase and serotonin. Ultrastructural analysis of glomus cells in Case 1 showed a marked decrease in the frequency of dense core vesicles (< 20% of control), the storage site of amine and peptide neurotransmitters. Immunostaining for S100 protein, a marker of sustentacular or Type II cells, was increased up to twofold compared with controls. In the lung, the frequency and size of NEB immunostained for bombesin was increased twofold in both cases, suggesting compensatory hyperplasia of airway chemoreceptors. Since intact peripheral chemoreceptors are essential for respiratory control, especially the response to hypoxia, abnormalities in CB and NEB may contribute to the pathophysiology of CCHS and related conditions such as sudden infant death syndrome (SIDS).

Congenital central hypoventilation syndrome (Ondine's curse syndrome) in two siblings: delayed diagnosis and successful noninvasive treatment

Congenital central hypoventilation syndrome (CCHS, Ondine's curse syndrome) is a rare respiratory disorder; less than 100 cases have been reported. Familiality of the disease has been discussed, but only few familial cases have been reported so far. In this report we describe the occurrence of CCHS in two male siblings. Diagnosis was established only at the age of 4 years in the first case, although the patient had disease related symptoms since early infancy. The second patient was one of dizygotic twins, he was diagnosed with CCHS at the age of 8 months. Up to that age only moderate desaturations had been observed. The other twin was unaffected by the disease. Both patients were successfully treated by nocturnal positive-pressure ventilation via a specially adapted face mask. They show satisfactory physical and neurologic development.

CONCLUSION

Our cases support the assumption of familiality in CCHS although the mode of inheritance remains to be clarified. Polygraphic recordings including capnography should be performed in siblings of CCHS patients early in life in order to avoid secondary complications. Noninvasive treatment by ventilation via special face masks is feasible.

Congenital central hypoventilation syndrome: mutation analysis of the receptor tyrosine kinase RET

Congenital central hypoventilation syndrome (CCHS) usually occurs as an isolated phenotype. However, 16% of the index cases are also affected with Hirschsprung disease (HSCR). Complex segregation analysis suggests that CCHS is familial and has the same inheritance pattern with or without HSCR. We postulate that alteration of normal function of the receptor tyrosine kinase, RET, may contribute to CCHS based on RET's expression pattern and the identification of RET mutations in HSCR patients. To further explore the nature of the inheritance of CCHS, we have undertaken two main routes of investigation: cytogenetic analysis and mutation detection. Cytogenetic analysis of metaphase chromosomes showed normal karyotypes in 13 of the 14 evaluated index cases; one index case carried a familial pericentric inversion on chromosome 2. Mutation analysis showed no sequence changes unique to index cases, as compared to control individuals, and as studied by single strand conformational polymorphism (SSCP) analysis of the coding region of RET. We conclude that point mutations in the RET coding region cannot account for a substantial fraction of CCHS in this patient population, and that other candidate genes involved in neural crest cell differentiation and development must be considered.

Congenital central hypoventilation syndrome: ocular findings in 37 children

BACKGROUND

Congenital central hypoventilation syndrome (CCHS) is a rare cause of central sleep apnea. Although ophthalmic abnormalities have been reported, the ocular findings have not been discussed in detail.

METHODS

We examined or obtained the records of 37 children with CCHS.

RESULTS

Twenty-seven patients were found to have abnormal pupils, most of which were miotic and reacted poorly to light. In 18 cases, the anterior surface of the iris was unusually smooth. Ten of the children with abnormal pupils also demonstrated light-near dissociation. Twenty had strabismus of various types, and 18 showed evidence of convergence insufficiency.

CONCLUSIONS

The high incidence of strabismus, pupillary abnormalities, and convergence insufficiency may be a result of neurologic defects in the midbrain.

Ventilatory responses to passive leg motion in children with congenital central hypoventilation syndrome

During exercise, children with congenital central hypoventilation syndrome (CCHS) demonstrate coupling of VE to exercise load, despite the absence of a VE response to changes in FICO2. To assess the effect of movement on VE, we studied six CCHS patients and six matched controls during passive motion in a motor-driven ergocycle at pedaling frequencies (PF) of 6 to 60 rpm. VE, VO2, VCO2, VT, heart rate, respiratory rate, SPO2, and PETCO2 were measured. During steady-state conditions, VE was constant at PF of 0 to 30 rpm, but increased at PF > or = 40 rpm in both controls and CCHS patients (p < 0.005). The increase in respiratory rate in CCHS patients was greater than in controls (p < 0.05) whereas VT increased similarly in both groups. At 60 rpm, VO2 increased in both groups, but VE/VO2 and VE/VCO2 increased in the CCHS patients and remained constant in the controls (P < 0.03; p < 0.04). From PF of 0 to 60, PETCO2 decreased from 47 +/- 7 to 41 +/- 6 mm Hg in the CCHS patients (p < 0.001) but remained unchanged in the controls (38 +/- 3 mm Hg; p = NS). An analysis of on-transient responses at 60 rpm revealed that VE increased immediately with the first breath after onset of motion in both groups, and that comparable differences in ventilatory patterns persisted in the two groups. We conclude that passive leg motion at PF > or = 40 increases VE in both CCHS patients and controls. In controls, VE was tightly coupled to VO2 and VCO2. However, in CCHS patients, passive leg motion elicited normalization of PETCO2.

[Continuous ambulatory monitoring in quality control of home therapy of congenital central hypoventilation syndrome (CCHS)]

4 children with congenital central hypoventilation syndrome (CCHS) now aged 6 to 9 years were studied for 1 to 8 years. In all patients CO2-response is missing, hypoxic drive is maintained. All patients required mechanical ventilation after birth. 1 patient is supported by controlled oxygen therapy during sleep since 9 months of age. 2 patients are IPPV-ventilated during sleep. 1 patient is pressure control ventilated with an oro-nasal mask since 6 years of age. All children showed phases of hypo- and hyperventilation (max. pCO2 107 mm Hg) depending on vigilance with respiratory acidosis in awake state and during sleep. These findings required ambulatory monitoring of home-therapy by a professional guard and continuous recording of pCO2 and pulseoximetry. These longtime data (max. pCO2 72 mm Hg) show that ambulatory monitoring and control of therapy is able to avoid extreme variation of blood gases and to stabilize acid-base regulation during sleeptime in patients with CCHS.

The complete spectrum of neurocristopathy in an infant with congenital hypoventilation, Hirschsprung's disease, and neuroblastoma

Neuroblastoma, Hirschsprung's disease, and central hypoventilation (Ondine's curse) are considered aberrations of neural crest cell growth, migration, or differentiation, and as such are considered to be under the general heading of neurocristopathy. Their combined occurrence in a newborn infant presenting with total colonic aganglionosis, central hypoventilation, and multifocal neuroblastoma had not been reported previously. A 2.3-kg white full-term girl required endotracheal intubation because of persistent apnea in the first hours of life. She had progressive abdominal distension and failure to pass meconium; a barium enema was performed, which showed microcolon with meconium pellets at the distal ileum. During laparotomy the distal ileum was found to be obstructed with inspissated meconium; an ileostomy and appendectomy were performed. The resected specimens were aganglionic. An additional 20 cm of aganglionic ileum was removed, and a normally innervated ileostomy was constructed. Numerous attempts at extubation failed because of apnea. The results of an extensive apnea workup, including electroencephalogram, magnetic resonance imaging (MRI), bronchoscopy, and pH probe study, were normal. Sleep studies showed congenital central hypoventilation syndrome, and the patient underwent a tracheostomy. At 3 months, an abdominal ultrasound examination performed within a septic workup showed a right suprarenal mass extending across the midline. Thoracic and abdominal MRI scans showed large bilateral adrenal and posterior mediastinal masses. The serum catecholamines and ferritin level were markedly elevated, suggestive of neuroblastoma. In light of the child's multiple problems, the family chose to forgo further workup (including a tissue biopsy) and therapy. In the following 2 months her tumor load rapidly progressed, and she died of respiratory insufficiency.(ABSTRACT TRUNCATED AT 250 WORDS)

Congenital central hypoventilation syndrome: cardiorespiratory responses to moderate exercise, simulating daily activity

Children with congenital central hypoventilation syndrome (CCHS) lack normal awake ventilatory responses to hypoxia and hypercarbia, yet engage in daily activities typical of similarly aged children. Our patients with CCHS are assessed annually with a walking treadmill protocol to assess physiologic responses to different levels of simulated daily activity. We hypothesized that children with CCHS (compared with age- and sex-matched healthy controls) would 1) exercise for shorter durations and reach lower peak speed and incline on the treadmill; 2) become more hypoxemic, more hypercarbic, and develop less tachycardia during activity; and 3) take longer to return to baseline oxygenation, ventilation, and heart rate than normal children. Seven children with CCHS [mean age, 6.9 +/- 3.0 (SD) years] who required 24 h/day ventilatory support (diaphragm pacers while awake and mechanical ventilation asleep) and 7 controls performed a walking protocol on a treadmill with progressive increments in speed and incline. Hemoglobin saturations (SaO2), end-tidal carbon dioxide concentrations (ETCO2), and heart rates (HR) were recorded at baseline conditions, during activity and during recovery. There were no significant differences between children with CCHS and controls in baseline values, duration of activity, peak speed, and incline achieved during walking and recovery time to baseline once the treadmill had stopped. However, children with CCHS became significantly more hypoxemic and hypercarbic during activity (P < 0.05), and they had a lower percent increase in HR during treadmill walking than controls (P < 0.05). These results offer the clinician an opportunity to adjust clinical management in children with CCHS by providing specific recommendations to parents about appropriate levels of activity for their children with CCHS.(ABSTRACT TRUNCATED AT 250 WORDS)

[Congenital central hypoventilation--treated with nocturnal biphasic intermittent respiration via nasal mask]

A case of congenital central hypoventilation syndrome (CCHS) was undiagnosed until the girl in question was eight years old. Her development was normal, although with symptoms and signs of nocturnal hypoventilation. At the age of eight, with an interval of eight months, she suffered two attacks of acute respiratory insufficiency necessitating intubation and respiratory treatment. The episodes were considered to be pneumonia/septicaemia, but were in retrospect proven to be lung congestion as a consequence of hypercapnia and hypoxaemia. After the last episode CCHS was confirmed. The difficulties in diagnosing CCHS are discussed. After extubation she has been successfully treated with nocturnal nasal intermittent positive pressure ventilation (NIPPV) with BiPAP (Respironic), and she has in this way avoided tracheostomy.

Anxiety and congenital central hypoventilation syndrome

OBJECTIVE

It has been hypothesized that individuals who cannot perceive elevations of CO2 will be less anxious than individuals with intact CO2 perception. To test this hypothesis, children with congenital central hypoventilation syndrome, who have a potentially lethal chronic illness associated with lack of CO2 perception and thus provide a natural experimental group, were studied.

METHOD

Rates of anxiety symptoms and disorders in children with congenital central hypoventilation syndrome (N = 13) were compared with rates in an age-matched, nonreferred group of community subjects (N = 292) that included subgroups of children with asthma (N = 15) and other chronic medical illnesses (N = 66). Anxiety symptoms were assessed with information obtained from structured interviews of the parents, which provided both total symptom scores and DSM-III-R diagnoses.

RESULTS

The children with congenital central hypoventilation syndrome exhibited significantly fewer anxiety symptoms than all other comparison subjects. Two of these children (15%) met criteria for anxiety disorders, a rate lower than that of the whole community group (24%) and of the chronically ill comparison subgroups (32%-47%). The largest difference in the prevalence of disorder emerged between the children with congenital central hypoventilation syndrome (15%) and those with asthma (47%). In the comparison of children with congenital central hypoventilation syndrome and children with other chronic illnesses, a priori analysis showed that the former had significantly lower rates of disorders that have been linked to panic in the literature.

CONCLUSIONS

This study supports theories of anxiety that implicate CO2 perception in the pathophysiology of panic and related anxiety states.

[Ondine syndrome: presentation of pediatric aspects based on a case report]

The congenital central alveolar hypoventilation syndrome (Undine's syndrome, or Ondine's curse) is a rare disorder of central ventilation. In recent years a successful therapy has been found consisting of pacing of the diaphragm. Early diagnosis is therefore significant for preoperative management. In our paper, we present the clinical course of a female newborn with Ondine's curse. Conclusions for the further management by the paediatric staff are demonstrated.

Daniel's story: congenital central hypoventilation syndrome

Central hypoventilation syndrome (CHS) is a disorder characterized by little or no ventilatory or arousal sensitivity to hypercapnia and variable reactivity to hypoxemia, with little or no hypoxic arousal responsiveness. CHS may be congenital or acquired and can be idiopathic or secondary to a known central nervous system abnormality. Infants often present with life-threatening apnea during quiet sleep and develop severe respiratory acidosis because of the inadequate response to hypercapnia and hypoxia. Long-term treatment usually involves use of mechanical ventilation during sleep.

Respiratory sensations in subjects who lack a ventilatory response to CO2

An urge to breath is perceived during breath hold and hypercapnia (termed 'air hunger') and during heavy exercise (often termed 'shortness of breath'). To better understand the neural mechanisms responsible for these sensations we studied five patients (8-17 years old) with congenital central hypoventilation syndrome (CCHS) who lack ventilatory response to CO2. CCHS patients reported no respiratory discomfort during CO2 inhalation or during maximal breath hold which was of much longer duration than age-matched controls. However, all 3 CCHS patients who exercised heavily reported some sensations akin to shortness of breath (they increased breathing nearly as much as controls). Our results are consistent with two possibilities. First, the air hunger of hypercapnia and breath hold is caused by projection to the forebrain of respiratory chemoreceptor afferents which bypass the respiratory centers, while exercise shortness of breath is caused by direct projections of limb afferents or locomotory center activity. Second, air hunger and shortness of breath share the same origin--projection of increased brain stem respiratory center motor activity (corollary discharge) to the forebrain.

Ondine-Hirschsprung syndrome (Haddad syndrome). Further delineation in two cases and review of the literature

Two unrelated children with congenital central hypoventilation syndrome (CCHS-Ondine syndrome) and long segment Hirschsprung disease are reported. Patient 1, a girl, is still alive at 3 years. Patient 2, a boy, died of viral pneumonia at 5.5 years. Continuous mechanical ventilation was necessary for months and those children could never be weaned from the respirator during sleep. Seventeen cases of this complex neurocristopathy are reviewed. Only six children (including our cases) survived beyond 2 years of age. Hypotonia, delay in developmental milestones or epilepsy were frequently observed. Ventilator dependency does not improve with time. Multifocal congenital neuroblastoma occurred in two children. Aetiology is unknown.

[Ondine's syndrome (alveolar hypoventilation)]

Ondine's syndrome is a rare condition characterised by alveolar hypoventilation during sleep on account of an abnormality in the automatic control of respiration. The respiration centre does not react adequately to the carbon dioxide tension in the blood required to maintain normal ventilation. We present a description of the course in an infant with congenital Ondine's syndrome because a therapeutic possibility is now available, viz, implantation of a phrenic nerve pacemaker. The infants showed respiratory insufficiency shortly after delivery. This disappeared on tactile stimulation. The infant had generalised hypotonia with absent patellar reflexes and weak sucking reflexes and, at the age of one week, seizures developed. The infant was treated with assisted ventilation but this could be reduced to use only during the period when the infant slept. The infant was in good health with normal psychomotor development until the age of two years. Plans had been made to implant a phrenic nerve pacemaker. Unfortunately, the infant developed Syncytial-virus pneumonia complicated by bacterial superinfection and developed severe anoxic brain damage which subsequently proved fatal.

Heart rate variability in congenital central hypoventilation syndrome

Heart rate variability was assessed in 12 patients with congenital central hypoventilation syndrome (CCHS) and in age- and sex-matched controls using SD of time intervals between R waves (R-R intervals), R-R interval histograms, spectral analysis, and Poincaré plots of sequential R-R intervals over a 24-h period using ambulatory monitoring. Mean heart rates in patients with CCHS were 103.3 +/- 17.7 SD and in controls were 98.8 +/- 21.6 SD (p greater than 0.5, NS). SD analysis of R-R intervals showed similar results in both groups (CCHS 102.2 +/- 36.0 ms versus controls 126.1 +/- 43.3 ms; p greater than 0.1, NS). Spectral analysis revealed that, for similar epochs sampled during quiet sleep and wakefulness, the ratios of low-frequency band to high-frequency band spectral power were increased for 11 of 12 patients with CCHS during sleep, whereas a decrease in these ratios was consistently observed in all controls during comparable sleep states (chi 2 = 20.31; p less than 0.000007). During wakefulness, the ratios of low-frequency band to high-frequency band spectral power were similar in both patients with CCHS and controls. Poincaré plots displayed significantly reduced beat-to-beat changes at slower heart rates in the CCHS patients (chi 2 = 24.0; p less than 0.000001). The scatter of points in CCHS Poincaré plots was easily distinguished from controls. All CCHS patients showed disturbed variability with one or more measures. The changes in moment-to-moment heart rate variability suggest that, in addition to a loss of ventilatory control, CCHS patients exhibit a dysfunction in autonomic nervous system control of the heart.

Neuropsychologic abnormalities in children with congenital central hypoventilation syndrome

We hypothesized that intellectual, neurodevelopmental, and visual-motor tests would be able to characterize the scope and nature of central nervous system involvement in children with congenital central hypoventilation syndrome. Age-appropriate intellectual (Brazelton Neonatal Behavioral Assessment, Bayley Scales of Infant Development, Wechsler Preschool and Primary Scale of Intelligence-Revised and Wechsler Intelligence Scale for Children--Revised), neurodevelopmental (Halsted-Reitan neuropsychologic battery), and visual-motor (Beery visual-motor integration test) tests were given to 17 children with congenital central hypoventilation syndrome (age 0.1 to 14.3 years). We found a broad range in IQ and developmental quotient, from greater than the 85th percentile to less than the 5th percentile, with discrepancies noted between verbal and performance measures. Multiple asymmetries and deficiencies of motor performance, not consistently related to handedness, were also found. Significant eye-hand coordination deficits were uncommon, but general performance was well below average. Full, verbal, and performance IQs and developmental quotients greater than or equal to 70 and less than 70 were compared by chi-square analysis with other associated conditions, including hours of ventilatory support, duration of initial hospitalization, growth, pulmonary hypertension, seizures, brain atrophy, central and peripheral hearing deficits, and ophthalmologic abnormalities; no statistically significant associations were found. These results lend support to the hypothesis that congenital central hypoventilation syndrome is a diffuse central nervous system process. However, the effects of transient hypoxia and associated conditions on neurodevelopmental test results cannot be excluded with certainty.

Upper airway function in Ondine's curse

Congenital central alveolar hypoventilation (Ondine's curse) is a rare disorder with absence of automatic control of ventilation but preservation of voluntary breathing. Phrenic pacing, used to treat this condition, is usually not successful without a tracheotomy. We performed fiberoptic videoendoscopy on an affected infant airway. During wakefulness and ventilation by a negative pressure ventilator, the airway was normal, but with sleep onset, passive inspiration produced phasic epiglottic collapse. This case demonstrates the importance of central control in maintaining upper airway patency.

Medical and psychosocial outcome of children with congenital central hypoventilation syndrome

We report the long-term medical and psychosocial outcome of 13 children with congenital central hypoventilation syndrome. One child (8%) died before initial hospital discharge. Of the remaining 12 children, 11 (92%) have been successfully cared for in their natural or foster parents' homes. Home ventilatory support was provided with positive-pressure ventilation, negative-pressure ventilation, or diaphragm pacers. After an initial lengthy hospitalization, children spent little time in the hospital. Severe medical complications were uncommon but included cor pulmonale (one child), poor growth (two children), and seizure disorder (three children). Most children functioned in the slow-learner range of mental processing, with a composite score (Kaufman Assessment Battery for Children) of 78 +/- 20 (SD); two were mentally retarded, and one functioned above the normal range. The children's care givers were assessed as having low levels of psychologic distress (Symptom Checklist 90--Revised) and good coping resources (Coping Resources Inventory) but a high level of marital discord. The children were able to attend school and partake in normal childhood activities. We conclude that with modern techniques for home ventilation, children with CCHS can have a good long-term medical and psychosocial outcome. We speculate that early diagnosis and the prevention of intermittent hypoxia will improve their physical and mental outcome.

Hypercapneic arousal responses in children with congenital central hypoventilation syndrome

Congenital central hypoventilation syndrome (CCHS, Ondine's curse) is generally thought to be due to insensitivity of the central chemoreceptors to carbon dioxide. Children with CCHS have absent ventilatory responses to both hypercapnea and hypoxia, suggesting either abnormal central and peripheral chemoreceptor function or abnormal central integration of chemoreceptor input. Because ventilatory and arousal responses to respiratory stimuli are distinct from each other, if children with CCHS have complete chemoreceptor dysfunction, one would predict that both ventilatory and arousal responses to respiratory stimuli would be abnormal. However, if they have abnormal central integration of chemoreceptor input for ventilation, they may still arouse to respiratory stimuli despite the absence of a ventilatory response. Hypercapneic arousal responses were tested in eight children with CCHS, aged 5.8 +/- 1.2 (SEM) years, and seven healthy control subjects, aged 4.4 +/- 1.1 years. Children were studied during sleep while normal ventilation was maintained using their home ventilators. Hypercapneic challenges were performed by rapidly increasing the inspired carbon dioxide tension to 60 mm Hg and maintaining this level until the child aroused or for a maximum of 3 minutes. Of children with CCHS, 87.5% aroused to hypercapnea, compared with 100% of control children. There was no significant difference in arousal between children with CCHS and normal control subjects. It is concluded that most children with CCHS arouse to hypercapnea, indicating the presence of some central chemoreceptor function. It is speculated that because these children do respond to hypercapnea, the most probable mechanism for CCHS is a brainstem lesion in the area where input from both chemoreceptors is integrated.

CCHS and home care

Caring for a child with CCHS at home can be a challenge to home care nurses. Family support and advocacy are imperative.

Hypercapnic and hypoxic ventilatory responses in parents and siblings of children with congenital central hypoventilation syndrome

Children with congenital central hypoventilation syndrome (CCHS) have abnormal ventilatory responses to metabolic stimuli. As there is a genetically determined component of chemoreceptor sensitivity, parents and siblings of children with CCHS may also have blunted ventilatory responses to hypercapnea and hypoxia. To test this, we studied hypercapnic ventilatory responses and hypoxic ventilatory responses in six mothers, four fathers, and five siblings (6 to 49 yr of age) of seven children with CCHS and compared them with 15 age- and sex-matched control subjects (5 to 47 yr of age). Pulmonary function tests were not different between relatives of children with CCHS and control subjects. To measure hypercapnic ventilatory responses, subjects rebreathed 5% CO2/95% O2 until PACO2 reached 60 to 70 mm Hg. To measure hypoxic ventilatory responses (L/min/% SaO2), subjects rebreathed 14% O2/7% CO2/balance N2 at mixed venous PCO2 until SaO2 fell to 75%. All tests were completed in less than 4 min. Instantaneous minute ventilation, mean inspiratory flow (tidal volume/inspiratory time), and respiratory timing (inspiratory timing/total respiratory cycle timing) were calculated on a breath-by-breath basis. Hypercapnic ventilatory responses were 1.97 +/- 0.32 L/min/mm Hg PACO2 in children with CCHS relatives and 2.23 +/- 0.23 L/min/mm Hg PACO2 in control subjects. Hypoxic ventilatory responses were -1.99 +/- 0.37 L/min/% SaO2 in the relatives and -1.54 +/- 0.25 L/min/% SaO2 in the control subjects.(ABSTRACT TRUNCATED AT 250 WORDS)

Congenital central alveolar hypoventilation syndrome (Ondine's Curse): effectiveness of early home ventilation for normal development

An 8 month old Caucasian girl, with congenital central alveolar hypoventilation syndrome (Ondine's Curse), was discharged with her home ventilation managed by her parents. Her subsequent neurophysical development assessed at 22 months of age was satisfactory.

Congenital difficulties with swallowing and breathing associated with maternal polyhydramnios: neurocristopathy or medullary infarction?

Two babies with congenital difficulties in swallowing and breathing are presented and contrasted. Both were associated with maternal polyhydramnios, but one was due to medullary infarction and the other to a malformation ("neurocristopathy"). In the former case, isolated tenth and twelfth cranial nerve palsies provided the clue as to the correct etiology, whereas the latter baby had dyscoordination of swallowing and breathing with sleep apnea ("Ondine's curse"). It is somewhat ironic that the case without a difficult delivery had the infarct, probably prenatal in onset, whereas the one with a difficult delivery had the congenital malformation. Neural crest cells are known to migrate widely and to develop greatly different functions, but the fact that their central associations of neural tube origin may also be affected has not previously been emphasized in the etiopathogenesis of the congenital malformation. A variety of syndromes with combinations of many defects may be seen in which too many or too few cells are formed, with more or less serious consequences especially for the respiratory and gastrointestinal systems.

Hypoxic and hypercapnic ventilatory responses in awake children with congenital central hypoventilation syndrome

Congenital central hypoventilation syndrome (CCHS) has been thought to be a disorder of central chemoreceptor responsiveness. Previous studies in CCHS have shown decreased or absent ventilatory responsiveness to both hypercarbia and hypoxia. However, hypoxic responsiveness during wakefulness has not been systematically studied. We studied hypoxic and hypercapnic ventilatory responses during wakefulness in five children with CCHS (6 to 11 yr of age). To measure the hypercapnic response, the children rebreathed a hyperoxic hypercapnic mixture until PaCO2 reached 56 to 69 mm Hg. For the hypoxic response, the children rebreathed a hypoxic gas mixture, at mixed venous PCO2, until SaO2 had fallen to less than 78%. We found that the ventilatory responses to hypercapnia and hypoxia were very variable (linear correlation coefficients ranging from -0.44 to +0.63 for hypercapnic responses and from -0.15 to +0.77 for hypoxic responses), with no significant change from baseline in response to either stimulus. There was no evidence of progressive ventilatory stimulation despite increasing stimulus. Additionally, these children had no subjective sensation of dyspnea or discomfort. This establishes that hypoxic and hypercapnic ventilatory control is absent during wakefulness. Chemoreceptor control (peripheral and central) is, therefore, defective in all states in children with CCHS. We speculate that the defect in CCHS lies in central integration of the central and peripheral chemoreceptor signals.

Congenital central hypoventilation syndrome associated with multiple ganglioneuromas

A five-year-old girl had congenital central hypoventilation syndrome and mediastinal and adrenal tumors. The mediastinal mass was though to be present, retrospectively, for at least four years prior to surgery. Pathology of the excised tumors revealed benign ganglioneuromas. This is the first case reported of an association between CCHS and multiple ganglioneuromas. This suggests that CCHS, like neural crest tumors, may result from maldevelopment of the embryonic neural crest.

Diaphragm pacing in infants and children. A life-table analysis of implanted components

Since 1976, we have implanted bilateral phrenic nerve electrodes for diaphragm pacing in 33 infants and children. This population includes 23 patients with congenital central hypoventilation syndrome (CHS), two with late onset CHS and hypothalamic dysfunction, three with hypoventilation associated with Chiari II malformation and myelomeningocele, and five with quadriplegia. Our experience, totalling 192 system-years and 96 patient-years of pacing, has enabled us to document the nature and frequency of problems related to the implanted components of the Avery Laboratories (S-232-1) pacemaker system when used in a pediatric population. By life table analysis, the mean time to need for replacement of any implanted component was 56.3 months. A total of 26 failures requiring component replacement occurred and were classified into four types: (1) receiver failure (15 cases), (2) electrode wire or wire insulation breakage (six cases), (3) infection requiring diaphragm pacer system removal (three cases), and (4) mechanical nerve injury (two cases). We conclude that the present diaphragm pacing system is effective but not without risk of biomedical component failure. The present system might be substantially improved by (1) a modified receiver design with a hermetic seal to prevent fluid penetration, (2) stronger, better insulated electrode wires, and (3) modifications of surgical technique and electrode type to prevent phrenic nerve damage.

Hirschsprung's disease, Ondine's curse, and neuroblastoma--manifestations of neurocristopathy

The term neurocristopathy has been applied to the association of Hirschsprung's disease, Ondine's curse (Congenital Hypoventilation Syndrome) and congenital neuroblastoma. Eight newborns with Hirschsprung's disease and Ondine's curse are discussed. Five of these have been seen by the authors. The remaining three patients are reported in the literature. In six of the infants (5 of ours, 1 from the literature) total colonic aganglionosis was found. Congenital neuroblastoma was present in two of the infants. In infants presenting with Hirschsprung's disease (especially of the long segment type) and breathing difficulties, the presence of a neurocristopathy should be considered.

Long-term follow-up of children with congenital central hypoventilation syndrome

The long-term clinical course of six patients with congenital central hypoventilation syndrome is described. During the neonatal period, the patients had prolonged apneas and hypoventilation, in the absence of cardiac, pulmonary, or neuromuscular disease. After an initial period of respirator dependency, they became able to sustain normal gas exchange while awake. During sleep, however, profound hypoventilation developed, and tracheostomy and mechanical ventilation were required. Ventilatory responses to hypercapnia and hypoxia were depressed or absent and did not improve with time. One patient was able, at 2 years of age, to breathe spontaneously during sleep with only moderate hypoventilation. The others, now 4 to 14 years of age, still need ventilatory support during sleep. Complications, such as cardiac failure and hypoxic seizures, mostly occurred early in the course and resolved with correction of insufficient mechanical ventilation. Speech acquisition was possible with the use of a special stoma plug. All patients were managed at home, and with appropriate support, the parents were able to provide safe ventilatory care with low morbidity and no mortality.

Auditory brainstem response (ABR) in congenital central alveolar hypoventilation

Auditory brainstem responses (ABRs) were studied in a child with congenital central alveolar hypoventilation showing marked depression of respiratory drive during sleep. During wakefulness and normoventilation no ABR abnormalities were found, either at the age of 14 months or five years. ABR recordings during sleep at 14 months of age showed marked wave V latency and wave I to wave V interpeak latency prolongation of about 0.4 ms both for periods of hypoventilation and normoxic hypercapnia. ABR findings of this and other studies carried out in sleep apneas are discussed with respect to brainstem dysfunction associated with varied sleep apnea syndromes.

Ventilatory effects of almitrine bismesylate in congenital central hypoventilation syndrome

Patients with congenital central hypoventilation syndrome (CCHS) lack hypercapnic and hypoxic stimulation of ventilation but have demonstrated carotid body function in response to hyperoxia and to pharmacological stimulation with doxapram. This study investigated the ventilatory effects of almitrine bismesylate, a carotid body stimulant, in 12 patients with CCHS. Measurements of minute ventilation, tidal volume (VT), respiratory rate (RR) and transcutaneous PO2 (TCPO2) were taken before and after administration of 4.5 mg/kg and 6 mg/kg of almitrine. Twenty-four hour pharmacokinetic studies were performed in 7 patients who received 4.5 mg/kg and in 6 patients who received 6 mg/kg almitrine. There was no significant improvement in ventilatory and gas exchange parameters at either dose of almitrine despite appropriate peak serum concentration of the drug at the time of the studies. These results suggest that almitrine is not a useful ventilatory stimulant in children with CCHS.

[Regulation of respiration during sleep in congenital central sleep apnea]

We report on 2 children aged 13 and 14 months with congenital central alveolar sleep apnea which showed depression of respiratory drive during sleep resulting from dysfunction of central chemoreceptors. Hypoventilation was found to be more severe during NREM sleep (minimum of alveolar ventilation in stages 3/4) than during REM sleep. During NREM sleep arousal responses to hypoxia proved to be an important factor in influencing the level of alveolar ventilation and in preventing fatal asphyxia.

[Respiratory function during wakefulness and sleep in a 7-year-old child with congenital alveolar hypoventilation of central origin]

Pulmonary function tests were performed in a 7 year-old girl with central alveolar hypoventilation syndrome treated with mechanical ventilation during sleep. Results showed: 1. during wakefulness decrease in residual functional capacity, in dynamic lung compliance and in lung transfer factor for CO; 2. during sleep the characteristics of the syndrome as reported in the neonatal period i.e. central alveolar hypoventilation in stages 2 and 3-4 which justified maintenance of mechanical ventilation when asleep.