Obstructive sleep apnea in infants

Supraglottoplasty for sleep endoscopy diagnosed sleep dependent laryngomalacia

OBJECTIVES

To evaluate the polysomnographic outcomes of supraglottoplasty (SGP) performed for sleep endoscopy diagnosed sleep dependent laryngomalacia as treatment for obstructive sleep apnea syndrome (OSAS).

METHODS

Nine subjects aged 6-55 months underwent supraglottoplasty for sleep dependent laryngomalacia. All subjects underwent both pre- and post-procedural polysomnograms.

RESULTS

Supraglottoplasty for sleep dependent laryngomalacia resulted in improvement of OSAS as measured by collective improvements in 8 different primary polysomnogram parameters: apnea-hypopnea index (AHI), minimum (nadir) and mean oxygen saturation, mean and maximum carbon dioxide, total sleep time, sleep efficiency, arousal index, as well as improvement in weight for length percentiles. Subjects had a significant 80% decrease in percentage change in AHI (p<0.005), with decrease in mean AHI from 23.4 to 4.8 following supraglottoplasty. Seven of 9 subjects demonstrated improvement in nadir saturations, 6 of 9 subjects had improvement in sleep efficiency, and 7 of 8 subjects under 4 years of age had improvement in weight for length percentile.

CONCLUSIONS

Supraglottoplasty for sleep dependent laryngomalacia is an effective treatment of OSAS, and can be readily diagnosed using sleep endoscopy. Further investigation is warranted to increase awareness and outcomes related to sleep dependent laryngomalacia.

Pierre Robin sequence: review of diagnostic and treatment challenges

Pierre Robin sequence is not a rare condition and paediatric specialists caring for respiratory related issues are likely to encounter cases in their practice. There have been a few recent reviews on the topic, mostly focusing on the surgical interventions performed for cases with severe airway obstruction. In the present review, we will highlight the different challenges that remain today in the global evaluation of infants afflicted with this condition through a thorough review of the medical literature, giving the clinician a full scope of the disease and of the various management options. The need for an improved objective evaluation of airway obstruction and for a better classification will be emphasized. We are therefore proposing a novel classification scheme that will better account for respiratory and feeding difficulties in these infants. Finally, many knowledge gaps persist regarding this condition, underlining the necessity for further research both in the genetic field and regarding the outcome of therapy.

Infants with viral bronchiolitis demonstrate two distinct patterns of nocturnal oxyhaemoglobin desaturation

AIM

This study aimed to demonstrate that viral bronchiolitis is associated with intermittent oxygen saturation of haemoglobin (SpO2 ) drops (≥3%) and low basal SpO2 between episodes of haemoglobin desaturation.

METHODS

Infants with bronchiolitis underwent pulse oximetry during the first night following hospital admission and a subgroup of them underwent repeat oximetry before hospital discharge. Oximetry was also performed in infants with partial upper airway obstruction (UAO) and without lung disease and in control participants without UAO or lung disease.

RESULTS

We enrolled 53 infants: 21 with bronchiolitis, 11 with UAO and 21 healthy controls. Participants with bronchiolitis had lower basal SpO2 (median 93.7% [10th-90th percentiles: 91.1-96.8]) than the subjects with UAO (96.9% [95.3-98.1]; p < 0.01) or the controls (98.7% [96.9-99.3]; p < 0.01). The bronchiolitis group was not different from the UAO group regarding the desaturation index (23.3 episodes/hour [10.3-46.6] and 15.5 episodes/hour [5.4-36.4], respectively; p = 0.08), but differed significantly from the controls (3.1 episodes/hour [0.3-5.5]; p < 0.01). The basal SpO2 and desaturation index improved in 10 subjects with bronchiolitis who had follow-up oximetry before discharge, but these indices remained abnormal when compared to values in the control group.

CONCLUSION

Bronchiolitis was characterised by low nocturnal basal SpO2 and intermittent SpO2 drops.

Statistical and nonlinear analysis of oximetry from respiratory polygraphy to assist in the diagnosis of Sleep Apnea in children

Obstructive Sleep Apnea-Hypopnea Syndrome (OSAHS) is a sleep related breathing disorder that has important consequences in the health and development of infants and young children. To enhance the early detection of OSAHS, we propose a methodology based on automated analysis of nocturnal blood oxygen saturation (SpO(2)) from respiratory polygraphy (RP) at home. A database composed of 50 SpO(2) recordings was analyzed. Three signal processing stages were carried out: (i) feature extraction, where statistical features and nonlinear measures were computed and combined with conventional oximetric indexes, (ii) feature selection using genetic algorithms (GAs), and (iii) feature classification through logistic regression (LR). Leave-one-out cross-validation (loo-cv) was applied to assess diagnostic performance. The proposed method reached 80.8% sensitivity, 79.2% specificity, 80.0% accuracy and 0.93 area under the ROC curve (AROC), which improved the performance of single conventional indexes. Our results suggest that automated analysis of SpO(2) recordings from at-home RP provides essential and complementary information to assist in OSAHS diagnosis in children.

Comorbidities in infants with obstructive sleep apnea

STUDY OBJECTIVE

The clinical characteristics of obstructive sleep apnea (OSA) in infants have been insufficiently characterized. Our aim was to describe identifiable comorbidities in infants with obstructive sleep apnea, which may assist in recognizing these patients earlier in their disease course and help improve management.

METHODS

This was a single-center, retrospective study involving infants 0-17 months of age with a diagnosis of OSA on the basis of clinical features and nocturnal polysomnography (PSG) at the Mayo Clinic Center for Sleep Medicine between 2000 and 2011. Patients were excluded if they had central apnea accounting for greater than 50% of respiratory events. OSA severity was determined by the apnea-hypopnea index (AHI).

RESULTS

One hundred thirty-nine patients were included. Based upon the AHI, they were subdivided into mild (AHI <5; 30%), moderate (AHI 5-9; 30%), or severe (AHI >10; 40%) categories. Comorbidities included gastroesophageal reflux in 95/139 (68%), periodic limb movements in sleep in 59/139 (42%), craniofacial abnormalities in 52/139 (37%), neuromuscular abnormalities in 47/139 (34%), prematurity in 41/139 (29%), genetic syndromes in 41/139 (29%), laryngomalacia / tracheomalacia in 38/139 (27%), and epilepsy in 23/139 (17%) of subjects. Severity of OSA correlated with prematurity, having a genetic syndrome, or neuromuscular abnormality. Multispecialty evaluation was needed for 119/139 (86%).

CONCLUSION

Comorbidities in infants with OSA differ from those of older children. Based upon the comorbidities identified in our study population, it appears that appropriate management of infants with OSA requires a multidisciplinary approach involving genetics, gastroenterology, pulmonology, otolaryngology, neurology, and general pediatrics.

Public health implications of obstructive sleep apnea burden

OBJECTIVE

To assess the implications of obstructive sleep apnea (OSA) burden among Indian children.

METHODS

MonteCarlo simulations were performed in order to estimate the number of OSA related obesity cases among Indian children (1-14 y of age) and the number of cases of stroke, coronary heart disease (CHD) and type 2 diabetes, considered as main adverse outcomes of OSA related childhood obesity, according to untreated and treated [adenotonsillectomy (AT) alone and AT associated to continuous positive airway pressure (CPAP)] pediatric OSA. Data used to perform MonteCarlo simulations were derived from a review about current literature exploring OSA related obesity.

RESULTS

The analysis on the number of adverse outcomes according to treated and untreated obesity related to OSA showed that treatments reduce the number of obesity cases, resulting in a great reduction of the amount of stroke, CHD and type 2 diabetes cases. However, the cost for treating adverse outcome was higher in patients treated for obesity related to OSA compared to those not receiving any treatment.

CONCLUSIONS

The reduction in the number of adverse outcomes due to treatment of obesity related OSA implicates the urgent need for public health policies in providing screening for OSA among children population: an early detection and a consequently prompt reaction to pediatric OSA could improve the burden of OSA related obesity.

Obstructive sleep apnea in infancy: a 7-year experience at a pediatric sleep center

PURPOSE

To investigate the common indications for polysomnogram (PSG) associated co-morbid conditions, evaluation strategies, treatment options, and outcomes in a series of infants diagnosed with obstructive sleep apnea (OSA) by a PSG.

METHODS

Retrospective chart review of infants who underwent PSG over a 7-year period was done. Infants with PSG diagnosed OSA were included in this study.

RESULTS

A total of 97 infants (59 males, mean age 4.6 months, standard deviation 3.3 months) were diagnosed with OSA (AHI ≥ 1/hr) based on PSG. The most common indication for PSG in infants were excessive snoring (53%) followed by nocturnal desaturations (24%). Associated co-morbid conditions included gastro-esophageal reflux (30%), laryngomalacia (24%), and craniofacial abnormalities (16%). Genetic abnormalities were found in 53%, of which trisomy 21 was the most common. Surgical treatments were employed in 36% and oxygen therapy in 15%. Thirty-eight patients were followed up with a repeat sleep study after a median interval of 8 months (range 1-24 months), of whom 26/38 had resolution of symptoms. Twenty-seven patients (28%) were followed clinically after a mean interval of 5 months of intervention (range, 1-34.5 months), in whom the symptoms resolved in 23/27 patients. Seven patients were deceased at review. Causes of death included status epilepticus, respiratory failure, hepatic failure, kidney failure, or unknown causes.

CONCLUSION

The etiologies of OSA in infants are different when compared to older children. PSG is feasible and a valuable tool in the diagnosis of OSA in infants and may help determine timely and appropriate evaluation and interventions. Clinical improvement in symptoms and resolution of PSG parameters were noted following medical and/or surgical interventions. Prospective studies need to be done to ascertain the long-term outcome of infants diagnosed with OSA to assess the benefits of early intervention on their neurocognitive development.

Associations between adenotonsillar hypertrophy, age, and obesity in children with obstructive sleep apnea

OBJECTIVE

To investigate the contributions of adenoid and tonsil size to childhood obstructive sleep apnea (OSA) and the interactions between adenotonsillar hypertrophy, age, and obesity in children with OSA.

METHODS

In total, 495 symptomatic patients were recruited. The patients were assigned to four groups according to age: toddler (age 1-3, n=42), preschool (age 3-6, n=164), school (age 6-12, n=200), and adolescence (age 12-18, n=89). All subjects had tonsil size graded by otolaryngologists, adenoid size determined on lateral radiographs (Fujioka method), and a full-night polysomnography. The apnea-hypopnea index (AHI), adenoid size, and tonsil size were compared in obese and non-obese children in the four age groups. Adjusted odds ratios (ORs) and 95% confidence interval (CI) of adenotonsillar hypertrophy and OSA risk were estimated by multi-logistic regression.

RESULTS

The AHI was positively related to tonsil grade (r=0.33, p <0.001) and adenoid size (r=0.24, p <0.01) in all patients. Tonsil grade was positively related to AHI in all four age groups. Adenoid size was positively related to AHI in the toddler, preschool, school groups, but not in the adolescent group (r=0.11, p=0.37). Tonsil grade and adenoid size were both positively related to AHI in obese and non-obese children. In the regression model, obesity (OR=2.89; 95% CI 1.47-5.68), tonsillar hypertrophy (OR=3.15; 95% CI 2.04-4.88), and adenoidal hypertrophy (OR=1.89; 95% CI 1.19-3.00) significantly increased OSA risk.

CONCLUSIONS

Adenotonsillar hypertrophy and obesity are the major determinants of OSA in children. However, the influence of adenoid size decreases in adolescence.

Physiological effects of obstructive sleep apnea syndrome in childhood

Sleep disordered breathing in children refers to a group of respiratory disorders that occur or are exacerbated during sleep. Obstructive sleep apnea syndrome (OSAS) is one of the most significant disorders in this group. OSAS can present in all age groups from early infancy to adolescent years. The cardinal feature of OSAS is limitation of inspiratory flow and volume during sleep resulting in abnormal gas exchange and/or alteration of sleep patterns. When OSAS is a chronic condition it often results in adverse physiological effects that impact on health and development. The present review discusses genesis of OSAS in children and consequent end organ injury with special emphasis on behavior and cognition, cardiovascular function, autonomic regulation, inflammation, endothelial function and metabolic syndrome.

Obstructive sleep apnea syndrome (OSAS) in children with Class III malocclusion: involvement of the PHOX2B gene

PURPOSE

The aim of this study is to provide new molecular approaches to the children with obstructive sleep apnea syndrome by evaluating the possible involvement of the PHOX2B gene, notoriously associated to congenital central hypoventilation syndrome (CCHS), in Class III malocclusion.

METHODS

Fifty subjects with Class III malocclusion, aged from 8 to 14 years, and with history of sleep apneic episodes, and 20 age-matched controls were submitted to genomic DNA examination from oral cells to specifically analyze the PHOX2B genotype.

RESULTS

Point "silent" mutations affecting different nucleotides of the PHOX2B gene were observed in 32 % of patients with Class III malocclusion and never in controls (0 %).

CONCLUSION

The genetic data obtained in this study in children with Class III malocclusion and sleep-related breathing disorders provide new information useful to the genetic characterization of this pathology. The PHOX2B gene silent mutations can lead to structural and functional modification of their product providing to a group of children with Class III malocclusion similar features to those of CCHS (sleep apnea episodes and craniofacial malformations).

Making sense of oxidative stress in obstructive sleep apnea: mediator or distracter?

Obstructive sleep apnea is increasingly recognized as an important contributor to cognitive impairment, metabolic derangements, and cardiovascular disease and mortality. Identifying the mechanisms by which this prevalent disorder influences health outcomes is now of utmost importance. As the prevalence of this disorder steadily increases, therapies are needed to prevent or reverse sleep apnea morbidities now more than ever before. Oxidative stress is implicated in cardiovascular morbidities of sleep apnea. What role oxidative stress plays in neural injury and cognitive impairments has been difficult to understand without readily accessible tissue to biopsy in persons with and without sleep apnea. An improved understanding of the role oxidative stress plays in neural injury in sleep apnea may be developed by integrating information gained examining neural tissue in animal models of sleep apnea with key features of redox biochemistry and clinical sleep apnea studies where extra-neuronal oxidative stress characterizations have been performed. Collectively, this information sets the stage for developing and testing novel therapeutic approaches to treat and prevent, not only central nervous system injury and dysfunction in sleep apnea, but also the cardiovascular and potentially metabolic conditions associated with this prevalent, disabling disorder.