Leila Azevedo de Almeida

Cephalometric evaluation of facial pattern and hyoid bone position in children with obstructive sleep apnea syndrome.

OBJECTIVES To assess the development of face and hyoid bone in children with obstructive sleep apnea syndrome (OSAS) through lateral cephalometries. MATERIALS AND METHODS Children aged 7-10 years with mixed dentition and with no previous otorhinolaryngologic, orthodontic or speech therapy treatments were studied. Twenty nasal breathers were compared to 20 mouth breathing children diagnosed as OSAS patients. All children underwent otorhinolaryngologic evaluation and cephalometries; children with OSAS also underwent nocturnal polysomnography in a sleep laboratory. RESULTS Children with OSAS presented increase in total and lower anterior heights of the face when compared to nasal breathers. In addition, children with OSAS presented a significantly more anterior and inferior position of the hyoid bone than nasal breathers. No significant differences in upper, anterior or posterior heights of the face were observed between groups. CONCLUSION The results suggest that there are evident and early changes in facial growth and development among children with OSAS, characterized by increased total and inferior anterior heights of the face, as well as more anterior and inferior position of the hyoid bone.

Adherence of obstructive sleep apnea syndrome patients to continuous positive airway pressure in a public service

INTRODUCTION The standard therapy for obstructive sleep apnea syndrome (OSAS) is continuous positive airway pressure (CPAP), but its correct and frequent use is essential to control the disease. PURPOSE To analyze adherence to CPAP among patients with OSAS treated in a multidisciplinary outpatient clinic of a public tertiary hospital. METHODS This was a retrospective study evaluating 156 patients with OSAS who underwent polysomnography for CPAP titration from 2008 to 2011. The patients were divided into two groups, those with good adherence to CPAP (a mean use of four or more hours per night) and those with poor adherence. The groups were compared regarding the following data: gender, age, body mass index, associated diseases, AHI at diagnostic polysomnography, and pressure (cmH2O) suggested by titration polysomnography. RESULTS 125 patients were analyzed, and it was observed that 82 of the patients (65%) had good adherence, whereas 43 (35%) showed poor adherence. Comparison between groups revealed that patients with a higher apnea-hypopnea index (AHI) were those who better adhered to treatment with CPAP. CONCLUSIONS the rate of adherence to CPAP among OSAS patients undergoing clinical monitoring at a public service was 65%. Patients with a higher AHI were those who adhered better to treatment with CPAP.

OSAS in children: where are we?

Brazilian Journal of otorhinolaryngology 77 (3) Maio/Junho 2011 http://www.bjorl.org.br / e-mail: revista@aborlccf.org.br In recent years, thanks to obvious developments in Sleep Medicine, we have had a better definition of the pathophysiological, clinical and therapeutical aspects associated with high prevalence disorders, such as the Obstructive Sleep Apnea Syndrome (OSAS). While the parameters are well defined and the outcomes have been better studied in the adult population; as far as children are concerned, medical literature is scarce in this context, which nonetheless has not prevented the development of new paradigms associated with Sleep Apnea in Children. It is widely known than OSAS cause facial morphometric changes, behavioral and cognitive disorders, as well as hyperactivity and attention deficit. Nonetheless, more recently it has been reported that it is also associated with metabolic and cardiovascular disorders, as well as an increase in insulin resistance and high blood pressure, amongst others, and it also causes the development of OSAS in adulthood. Having these new repercussions, childhood OSAS must be diagnosed and dealt with aggressively. In the Second Edition of the International Classification of Sleep Disorders, from 2005, childhood OSAS is defined based on clinical and polysomnographic criteria: complaint of snoring and difficult breathing during sleep, associated with other OSAS signs and symptoms, and polysomnography tests showing high rates of apnea +hypopnea ≥ 1/hour, hypoxemia, hyperscapnia, sleep fragmentation, and indirect evidence of increased airway resistance. With hypopnea episodes being part of the diagnostic criteria not only the apnea episodes, cases interpreted as “primary snoring” are currently considered “mild OSAS”. Since the hypopnea events are more subtle, the polysomnographic diagnosis of OSAS has been frequent in children, although parents do not report any important obstructive respiratory event during the night. In pre-surgical assessment, the role of diagnostic polysomnography becomes increasing more important do define borderline cases from the clinical standpoint, especially because the clinical predictors, such as tonsil size, have contradictory results: it is common to have children with severe OSAS and non-obstructive tonsils, and vice-versa. If, on the one hand polysomnography tests become increasingly relevant, on the other hand it must not be used as the sole tool used to classify disease severity. Children with the same apnea + hypopnea indices may have different clinical involvements, and a child with a higher index may be clinically better than another with a lower index. In general, cases with 1/h ≤HAI ≤ 5/h have mild involvement, and cases of HAI >5/h have moderate to severe involvement, depending on a more global evaluation of the polysomnography and, mainly, the clinical picture presented by the child. From the treatment standpoint, we have also gone through some rethinking. Adenotonsillectomy, traditionally curative for most of the cases, shows, based on new residual OSAS criteria, very disappointing cure rates of 25-60%. Results also vary according to methodological differences in the definition of residual OSAS; the strictest IAH ≤ 1/h, was associated to the resolution of only 27% of the cases in a recent multicentric study, with the caveat that approximately 50% of the sample was made up of obese patients. The most mentioned predictors of residual disease are obesity and severe disease at the time of the diagnosis. It is still unclear how much the medical interview during post-surgical evaluation is able to tell cured cases from residual cases. Without doubts, it must include not only questions about the presence of snoring and respiratory pauses during sleep, but also about restless sleep. Cognitive and behavioral improvements may or may not happen. Both from the diagnostic as well as the treatment standpoint we are seeing an ideal medicine, supported by complementary tests, and a possible medicine, as it is for so many other clinical entities. Having said that, when should one order a polysomnographic test? Such theme must lead to new standardizations. For now, it seems reasonable to order a polysomnographic study before tonsillectomy at least for: children with comorbidities; obese children; when suspecting a child has severe OSAS; and in order to define controversial cases. Polysomnography must be indicated after surgery in cases in which symptoms persist and in children with severe OSAS before the procedure. Paradoxically, new concepts put us face-to-face with old beliefs: anamneses must be careful in the pre and postoperative evaluations; each child must be assessed in a more holistic way; and, when the complementary test is available, it may not be able to establish clinical severity, and each should be assessed in an individual basis. And finally, we may be far from a cake recipe or a consensus, but we are, certainly, closer to the truth.

Central apnea after adenotonsillectomy in childhood: case report

Obstructive sleep apnea syndrome (OSAS) during childhood has a prevalence of 2–4%, and its main underlying cause is hypertrophy of the upper airway lymphoid tissues [1–3]. In children, central apnea (CA) may be part of OSAS or may occur as a physiological event of wake–sleep transition or REM sleep. However, although CA is considered to be common in healthy children, several authors have detected CA indices generally <1/h even when different criteria are used for the definition of the events [4–7]. The preponderance of CA in the context of OSAS should suggest secondary causes. CA presenting as a periodic breathing pattern is observed at a certain frequency only in premature babies or among children at high altitude. In older children, unless it occurs as a brief phenomenon at the beginning of sleep, a more expressive periodic breathing pattern may be associated with anomalies of the central nervous system [8]. Children with OSAS appear to have a higher central apnea index (CAI) than healthy children. A proposed underlying mechanism is a possible inhibitory action of mechanoceptors of the upper airways on the respiratory center causing CA in the presence of a pharyngeal collapse and obstruction [9]. Another possible mechanism regarding post-movement CA is that these events could be favored by a larger number of arousals induced by obstructive respiratory events [10]. More recently, a new entity called complex apnea syndrome (CAS) was described in adult patients with OSAS after treatment with a positive airway pressure (PAP) device, as the resolution of obstructive apneas is followed by the emergence of central ones [11–17]. CAS can represent a polysomnographic pattern that occurs due to different underlying mechanisms. These mechanisms are believed to involve PAP-dependent aspects like the lung stretch reflex and reduction of the anatomical dead space. Also, PAPindependent mechanisms, such as a possible increment of ventilation due to increased chemosensitivity that could develop over time of recurrent exposure to apnea and hypoxia, might also take part in these events. With increased ventilatory gain, small oscillations of CO2 could generate an over-compensatory response, leading to CA events. Sleep may uncover a high latent chemosensitivity as ventilation becomes more dependent on gas variations and is less modulated by the wakefulness ventilatory drive. Microarousals, while leading to a decreased CO2 tension, could be a trigger for CA. Although this mechanism is present under physiological conditions, only non-repetitive CA events are considered normal. A large number of CA can occur during L. A. de Almeida :A. L. Eckeli :H. H. Sander : R. M. F. Fernandes Department of Neuroscience and Behavioral Sciences— Neurology Division, Ribeirao Preto School of Medicine, University of Sao Paulo, Ribeirao Preto, SP, Brazil

EditorialOSAS in children: Where are we?

Brazilian Journal of otorhinolaryngology 77 (3) Maio/Junho 2011 http://www.bjorl.org.br / e-mail: revista@aborlccf.org.br In recent years, thanks to obvious developments in Sleep Medicine, we have had a better definition of the pathophysiological, clinical and therapeutical aspects associated with high prevalence disorders, such as the Obstructive Sleep Apnea Syndrome (OSAS). While the parameters are well defined and the outcomes have been better studied in the adult population; as far as children are concerned, medical literature is scarce in this context, which nonetheless has not prevented the development of new paradigms associated with Sleep Apnea in Children. It is widely known than OSAS cause facial morphometric changes, behavioral and cognitive disorders, as well as hyperactivity and attention deficit. Nonetheless, more recently it has been reported that it is also associated with metabolic and cardiovascular disorders, as well as an increase in insulin resistance and high blood pressure, amongst others, and it also causes the development of OSAS in adulthood. Having these new repercussions, childhood OSAS must be diagnosed and dealt with aggressively. In the Second Edition of the International Classification of Sleep Disorders, from 2005, childhood OSAS is defined based on clinical and polysomnographic criteria: complaint of snoring and difficult breathing during sleep, associated with other OSAS signs and symptoms, and polysomnography tests showing high rates of apnea +hypopnea ≥ 1/hour, hypoxemia, hyperscapnia, sleep fragmentation, and indirect evidence of increased airway resistance. With hypopnea episodes being part of the diagnostic criteria not only the apnea episodes, cases interpreted as “primary snoring” are currently considered “mild OSAS”. Since the hypopnea events are more subtle, the polysomnographic diagnosis of OSAS has been frequent in children, although parents do not report any important obstructive respiratory event during the night. In pre-surgical assessment, the role of diagnostic polysomnography becomes increasing more important do define borderline cases from the clinical standpoint, especially because the clinical predictors, such as tonsil size, have contradictory results: it is common to have children with severe OSAS and non-obstructive tonsils, and vice-versa. If, on the one hand polysomnography tests become increasingly relevant, on the other hand it must not be used as the sole tool used to classify disease severity. Children with the same apnea + hypopnea indices may have different clinical involvements, and a child with a higher index may be clinically better than another with a lower index. In general, cases with 1/h ≤HAI ≤ 5/h have mild involvement, and cases of HAI >5/h have moderate to severe involvement, depending on a more global evaluation of the polysomnography and, mainly, the clinical picture presented by the child. From the treatment standpoint, we have also gone through some rethinking. Adenotonsillectomy, traditionally curative for most of the cases, shows, based on new residual OSAS criteria, very disappointing cure rates of 25-60%. Results also vary according to methodological differences in the definition of residual OSAS; the strictest IAH ≤ 1/h, was associated to the resolution of only 27% of the cases in a recent multicentric study, with the caveat that approximately 50% of the sample was made up of obese patients. The most mentioned predictors of residual disease are obesity and severe disease at the time of the diagnosis. It is still unclear how much the medical interview during post-surgical evaluation is able to tell cured cases from residual cases. Without doubts, it must include not only questions about the presence of snoring and respiratory pauses during sleep, but also about restless sleep. Cognitive and behavioral improvements may or may not happen. Both from the diagnostic as well as the treatment standpoint we are seeing an ideal medicine, supported by complementary tests, and a possible medicine, as it is for so many other clinical entities. Having said that, when should one order a polysomnographic test? Such theme must lead to new standardizations. For now, it seems reasonable to order a polysomnographic study before tonsillectomy at least for: children with comorbidities; obese children; when suspecting a child has severe OSAS; and in order to define controversial cases. Polysomnography must be indicated after surgery in cases in which symptoms persist and in children with severe OSAS before the procedure. Paradoxically, new concepts put us face-to-face with old beliefs: anamneses must be careful in the pre and postoperative evaluations; each child must be assessed in a more holistic way; and, when the complementary test is available, it may not be able to establish clinical severity, and each should be assessed in an individual basis. And finally, we may be far from a cake recipe or a consensus, but we are, certainly, closer to the truth.

Cephalometric, muscular and swallowing changes in patients with OSAS

Obstructive Sleep Apnoea Syndrome (OSAS) is believed to be associated with craniofacial and neuromuscular changes, although the interplay among these variables still is poorly recognised. The objective of this study was to identify hyoid, muscular and swallowing changes associated with OSAS, and to correlate these alterations with OSAS severity. Cross-sectional study, in a tertiary referral centre. Seventy-two adult individuals participated in this study: 12 controls (without apnoea) and 60 patients with apnoea (mild, moderate and severe OSAS-20 individuals in each group). All participants were initially evaluated by otorhinolaryngologist and neurologist and underwent polysomnography for OSAS stratification. Cephalometric data, clinical myofunctional status and swallow videofluoroscopy exam were assessed. A hybrid effect model was used to analyse swallowing parameters; dependent variables were age, body mass index (BMI) and cephalometric measures. Individuals with OSAS presented lower hyoid position and narrower posterior airway distance when compared to controls. These parameters correlated to OSAS severity. Additionally, OSAS patients exhibited significantly lower myofunctional scores. Both velum and hyoid contraction times were significantly lower in the OSAS group at videofluoroscopy, regardless of its severity. Premature leakage into pharynx was more common in OSAS groups. Laryngeal penetration phenomenon occurred only in two patients (both from OSAS group). Our results suggest that hyoid bone position is associated with OSAS severity. Muscular pattern and swallowing are impaired in OSAS patients, irrespective of OSAS severity and facial profile. These findings indicate a higher predisposition of OSAS patients to present an inferior hyoid positioning, accompanied by myofunctional and swallowing disorders.

Cephalometric Evaluation of Facial Pattern and Hyoid Bone Position in Children with OSAS

Objective: The relation between craniofacial changes and OSAS in nonsyndromic children is not well established. The objective of the present study was to assess the development of face and hyoid bone in children with OSAS through lateral cephalometries. Method: Twenty nasal breathing children aged 7 to 10 years were compared with 20 matched in age children polysomnographically diagnosed as OSAS patients. All children underwent otorhinolaryngological evaluation and cephalometries. Results: Children with OSAS presented an increase in total and inferior anterior heights of the face when compared to nasal breathers. In addition, children with OSAS presented a significantly more anterior and inferior position of the hyoid bone than nasal breathers. No significant differences in superior anterior or posterior heights of the face were observed between groups. Conclusion: The results suggest that there are evident and early changes in facial growth and development among children with OSAS, characterized by increased total and inferior anterior heights of the face, as well as a more anterior and inferior position of the hyoid bone.