|
 
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| REVIEW ARTICLE |
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| Year : 2017 | Volume
: 1
| Issue : 3 | Page : 54-58 |
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A review of treatment options in paediatric sleep-disordered breathing
Yu-Shu Huang1, Christian Guilleminault2
1 Division of Child Psychiatry and Sleep Center, College of Medicine, Chang Gung Memorial Hospital, Taoyuan, Taiwan, Republic of China; Division of Sleep Medicine, Stanford University, Redwood City, CA, USA
2 Division of Sleep Medicine, Stanford University, Redwood City, CA, USA
| Date of Web Publication | 11-Oct-2017 |
Correspondence Address:
Christian Guilleminault
Division of Sleep Medicine, Stanford University, 450 Broadway Street, MC 5704, Redwood City, CA 94063
USA
 Source of Support: None, Conflict of Interest: None  | Check |
DOI: 10.4103/prcm.prcm_5_17
The clinical presentation of paediatric obstructive sleep apnoea (OSA) is different from that reported in adults. Children with paediatric OSA have more disturbed nocturnal sleep than excessive daytime sleepiness and present with more behavioural problems such as hyperactivity. They have sleep-related issues such as nocturnal enuresis and sleep-terrors and psychiatric problems such as depression and insomnia. Adenotonsillectomy has been the recommended treatment for paediatric OSA, but this practice as the initial treatment for all children has been questioned. The orthodontic approaches have been studied in children. Preliminary studies have suggested that rapid maxillary expansion and mandibular advancement with functional appliances may be effective even in children. Mandibular advancement devices, however, are not recommended for pre-pubertal children. These devices have been used in children in the late-teens, but long-term follow-up data are still lacking. Another non-invasive treatment is myofunctional therapy that has not been widely investigated. In syndromic children and where hypoventilation during sleep is present, positive airway pressure ventilation can be given. Nasal allergies are common in children. Increased nasal resistance impacts on breathing during sleep. Therefore, the treatment of nasal allergies with anti-inflammatory agents is an integral part of the management of paediatric OSA. Another important aspect of paediatric OSA is the presence of a short lingual frenulum and less frequently, a short nasal frenulum. They have been shown to cause abnormal growth of oral-facial region leading to OSA. Gastroesophageal reflux is both a cause and consequence of OSA and should be treated if present. The recent advance in the understanding of the pathogenesis of paediatric OSA lends hope that early recognition and management of factors that lead to the development of OSA may reduce the frequency of this disease and its sequelae. However, these factors are mostly unknown or ignored by specialists and general paediatricians during the early childhood orofacial development. Keywords: Adenotonsillectomy, lingual frenulum, myofunctional therapy, paediatric obstructive sleep apnoea
How to cite this article:
Huang YS, Guilleminault C. A review of treatment options in paediatric sleep-disordered breathing. Pediatr Respirol Crit Care Med 2017;1:54-8 |
How to cite this URL:
Huang YS, Guilleminault C. A review of treatment options in paediatric sleep-disordered breathing. Pediatr Respirol Crit Care Med [serial online] 2017 [cited 2023 May 31];1:54-8. Available from: https://www.prccm.org/text.asp?2017/1/3/54/216542 |
| Introduction | |  |
Paediatric obstructive sleep apnoea (OSA) was initially described in 1976.[1] In 1981, Guilleminault et al. published a review of fifty paediatric patients[2] which demonstrated that the clinical features of paediatric OSA were different from adults. The authors emphasised that these children had more disturbed nocturnal sleep than excessive daytime sleepiness, presented with more behavioural problems, especially school-related problems with attention deficit and hyperactivity (attention deficit hyperactivity syndrome) resulting in poor school performance. They can also present with nocturnal enuresis, sleep-terrors, sleep-walking and confusional arousals which are classified as non-rapid eye movement parasomnias. Hypersomnias, depression, insomnia and psychiatric problems are also noted. In Asia, Huang et al. reported that the common symptoms of paediatric OSA were similar with poor attention span, loud snoring, difficulty awakening and mouth breathing being the most commonly observed.[3]
The underlying causes of paediatric OSA are complex. Adenotonsillar hypertrophy, obesity, anatomical and neuromuscular factors are involved. In 1978, adenotonsillectomy (T&A) was suggested as a treatment of OSA. This was based on the concept that the presence of soft-tissue such as enlarged adenoids and tonsils could cause narrowing of the upper-airway, increased the risk of collapse of hypopharyngeal tissue during inspiration. This is still often considered as the treatment of choice in children. Following T&A, some patients still have features of OSA and others have reported an increased weight gain. There is currently no consensus as to the best mode of treatment for paediatric OSA probably because the best treatment should be tailored to the cause(s) of the OSA in each individual child.
| Treatment Options for Paediatric Obstructive Sleep Apnoea Syndrome | | |
There are no universally accepted guidelines for treatment of paediatric obstructive sleep apnoea syndrome. Treatment options for paediatric sleep-disordered breathing (SDB) include:
- T&A: The most common treatment for paediatric OSA
- Treatment of nasal allergies and radiofrequency treatment of enlarged turbinates
- Continuous positive airway pressure (CPAP) and bi-level positive airway pressure (BiPAP); positive airway pressure (PAP) ventilation can be used in all age groups
- Weight reduction in overweight/obese children
- Medications: Nasal decongestants, nasal steroids, and leukotriene inhibitors (montelukast) may be a therapeutic option for children with mild or residual OSA
- Palatal expanders and oral appliances, while mandibular advancement devices (MADs) can be considered for adolescents
- Other surgical procedures, for example, epiglottoplasty, mandibular distraction osteogenesis and maxillomandibular advancement and tracheotomy, which may be indicated in selected cases despite the fact that some of the surgical procedures performed in adults such as uvulopalatopharyngoplasty have been strongly recommended to avoid in children by the American Academy of Sleep Medicine.
The decision for the type of treatment is based on a combination of the available knowledge about potential cardiovascular, metabolic and neurocognitive sequelae and the clinical judgement of individual health-care professionals.
| Adenotonsillectomy | | |
For years, T&A has been the recommended treatment for paediatric OSA. In recent years, this practice has been put into question. First, many studies showed that T&A in paediatric OSA patients had variable results in achieving an apnoea-hypopnoea index (AHI) of 1 or less, with such results been observed in about 50% of cases and as low as 32% in obese children.[4],[5],[6],[7],[8] Furthermore, a long-term polysomnography (PSG) follow-up study[9] performed in children with OSA aged 6–12-year-old who had undergone T&A with sleep PSG performed 6 months, 12 months, 24 months and 36 months after T&A. It showed progressive worsening of AHI with time in 68% of the cohort.
The Childhood Adenotonsillectomy Trial study looked at children with low but abnormal AHI who delayed having a T&A. A repeat PSG after the initial investigation without T&A showed a change from the baseline study, but clinical symptoms may still be present.
Another study showed that T&A alone did not lead to the elimination of mouth breathing during sleep.[10] This might be due to the fact that children who were mouth-breathers for a certain length of time had a 'dis-use' of their nose when breathing during sleep and removal of the adenoids and tonsils did not restore them to normal nasal breathing during sleep.[10]
Paediatric OSA may be related to other factors limiting the size of the upper airway during sleep such as abnormalities of oral-facial structures. These abnormalities need to be corrected to restore normal airway flow.
| Orthodontic Treatment | | |
Preliminary studies[11],[12],[13],[14] suggested that orthodontic treatments, such as rapid maxillary expansion (RME) or mandibular advancement with functional appliances, may be effective in handling paediatric snoring and OSA. The introduction of RME or bi-maxillary expansion[15],[16] has shown that some children may not need T&A. These preliminary results suggested that the correction of mild abnormalities of cranio-facial structures reduced snoring and OSA in children and young adolescents and may be sufficient to avoid T&A and bring back nasal breathing during sleep.[15],[16]
RME is aimed at increasing the width of the palate by its action on the cartilaginous intermaxillary suture, an active facial growth centre active till 13–16 years of age. Bi-maxillary expansion combines the treatment on the intermaxillary suture with the expansion of the mandibular teeth as the alveolo-dental growth centre is also active till the same age. Mandibular expansion has less impact than RME.[17],[18],[19]
Studies combining the use of T&A and RME have shown that combination approach often provides better results than the single approach: There is a continuous interaction between nasal breathing and facial growth. Enlarged adenoids and tonsils impair nasal breathing which impacts on oral-facial growth which further narrows the upper airway.
| Myofunctional Therapy | | |
The non-restoration of nasal breathing during sleep leads to the recurrence of SDB. This was shown by both retrospective and prospective studies involving T&A alone and T&A with orthodontic therapies.
The use of myofunctional therapy (MFT) alone when dealing with paediatric SDB has not been widely investigated. Results of studies done on children with orthodontic problems have shown that isolated extensive and well-controlled MFT can lead to return to normal orofacial anatomy.[20],[21] In adults, there is reported improvement of OSA and snoring, but the long-term effect on SDB is unknown. Treatments with T&A or orthodontics without concomitant MFT has been shown to lead to persistence or recurrence of paediatric SDB.
MFT and proper tongue positioning in the oral cavity have been described since 1918 as leading to improvement in mandibular growth, nasal breathing and facial appearance. MFT is comprised of isotonic and isometric exercises that target oral (lip, tongue) and oropharyngeal structures (soft palate, lateral pharyngeal wall). Breathing, particularly nasal breathing, swallowing, mastication and suction are some of the daily functions that help the oral cavity gain growth during early childhood and participates in the normal development of the oral-facial structures. Normal development of oral-facial structures is important for air exchange, particularly during sleep. During childhood sleep, the tongue will be positioned against the palate and help widen the palate (the adult palatal width is between 40 and 50 mm). The continuous interaction of the tongue with active inter-maxillary synchondrosis and the alveolo-dental growth region are factors in the normal development of oral-facial structures.[20],[21],[22],[23] MFT[20],[21],[22],[23] aims to obtain appropriate head posture and positioning of the tongue on the palate against the upper teeth, appropriate swallowing and mastication using both sides and posterior chewing, appropriate breathing through the nose while keeping the mouth closed, and appropriate speech and articulation. MFT requires active parental involvement to obtain good results. Specialised educators exist in many countries, but educational programs vary widely in depth. A meta-analysis[20],[21],[22],[23] showed that MFT in association with other therapeutic approaches may lead to complete remission of OSA in about 60% of children with whom it is used. The major problem is compliance with daily exercises and continuous parental involvement with the training exercises of the child. This treatment approach is called 'active MFT'.[20],[21],[22],[23]
A 'passive MFT'[24] was reported recently. It calls upon the use of mandibular devices that will lead to sensory stimulation of the tongue leading to increased tongue muscle activity, but more work is needed. It showed that 6 months of passive MFT using an oral appliance with a tongue bead during sleep led to a reduction in the AHI in 63.6% of children.[24]
| Dental Devices in Paediatric Obstructive Sleep Apnoea | | |
MADs are not usually recommended in paediatric OSA and in particular pre-pubertal individuals. It has been tried in teenagers, but there is no long-term outcome information. Functional jaw appliances such as the Herbst appliance and Frankel functional appliances have been tried in children in the hope of increasing mandibular growth, but studies have shown that no growth beyond age-related growth could be seen with such appliances. In Taiwan, we have placed some children on the Herbst appliance between 12 and 17 years of age. The results were similar to that described in adult studies with dental devices. There was an improvement in the AHI when the teenager was wearing the device, but the OSA recurred once the appliance was removed. All these children underwent maxilla-mandibular-advancement surgery at 18 years of age. A similar experience was obtained with 6 children wearing the Biobloc™ devices. There was no long-term benefit demonstrated in children put on mandibular advancement devices. The only prospective study of devices in paediatric OSA compared with a controlled group which showed a benefit is the study post-usage of the device used to perform in passive MFT, and this study involves a small number of children.[24]
| Positive Airway Pressure Ventilation | | |
PAP ventilation can be considered in children with hypoventilation during sleep or in syndromic children or when other treatments have failed. It can be applied to children of all ages.[25]
Continuous-positive airway-pressure (CPAP) is usually considered in children with isolated upper airway problems. However, children with other problems besides upper airway obstruction such as obesity, syndromic children, connective tissues disorders (e.g., Marfan's, Ehlers–Danlos syndrome) or neuromuscular disorders (e.g., myotonic dystrophy, Duchenne muscular dystrophy), BiPAP is commonly required.
Compliance to treatment is a problem and parents have to be supported by the medical team during the training. Behavioural therapy during the daytime may be needed before children accept wearing the mask during sleep. Regular follow-up is needed as facial growth is continuous and dynamic during childhood. Re-calibration of pressures will be needed over time.
The major problem associated with PAP therapy in children is its effect on mid-facial growth due to the pressure of the masks on the developing facial bones.[26] Such changes occur as early as 12 months of starting therapy and are more obvious after 2 years of usage. The younger the child, the greater and more rapid is the impact. However, it can occur at any age.[27],[28] The use of chin-strap increases this negative effect. To reduce this effect, masks have been developed that apply pressure over the forehead instead of the midface structures. Regular orthodontic evaluation and daytime MFT have also been recommended to counteract this problem.
| Treatment of Nasal Obstruction | | |
Increased nasal resistance impacts on breathing during sleep. Nasal allergies are common in children and will lead to enlargement of the inferior and middle nasal turbinates leading to mouth breathing.[29] Allergies are associated with an increase in inflammatory mediators that play a role in enlarging the soft tissues located in the upper airway. The nasal passages should always be evaluated when OSA is suspected as the presence of enlarged nasal turbinates, a deviated nasal septum and enlarged adenoids and tonsils can contribute to upper airway obstruction.
The treatments for reducing nasal turbinate include the use of topical corticosteroid nasal spray especially in the presence of nasal allergies. These can be applied either intermittently or continuously for 3 months. In the case of intermittent use, the nasal sprays are applied for 4–6 weeks with a rest for 4 weeks before reapplying for a further 4–6 weeks. Leukotriene receptor antagonists such as montelukast can be given to reduce nasal congestion and for its anti-inflammatory properties. The treatment of nasal allergies also includes immunotherapy against a specific allergen identified on skin prick tests if indicated. Radiofrequency ablation therapy of the turbinates can be applied in children with severe nasal obstruction.
The management of a deviated nasal septum is not as clear. In the presence of complete obstruction of the nasal passage, surgery may be required. However, recurrences can occur if performed in a young child. If the deviated nasal septum is associated with a high and narrow palatal vault, orthodontic treatment with RME should be the first line treatment as widening the palatal vault will allow more space for spontaneous expansion of the nasal septum.
| Role of the Frenula | | |
A short lingual frenulum and less frequently, the nasal frenulum are known to cause abnormal growth of the oral-facial region leading to OSA.[30],[31] The presence of short frenula should be recognised at birth and surgical release should be done. It is controversial as to how early this clipping should be done. The current evidence suggest that surgical release should be performed within the 1st month of life for the best results. No long-term studies on its effect on tongue motility and oral-facial development is available. One important factor is the practice of 'stretching' the frenulum three to 4 weeks before and after the surgery, and this is done using daily MFT. Such a recommendation is crucial in treating a short frenulum.[32],[33],[34],[35]
| Role of Gastroesophageal Reflux | | |
Gastroesophageal reflux (GER) is both a cause and consequence of OSA and should be treated if present. It has also been associated with a short lingual frenulum. The abnormal inspiratory effort seen with obstructed breathing during sleep is associated not only with an increase in pleural pressure but also with an increase in abdominal pressure, leading to the development of GER. The presence of GER results in the presence of acid in the upper-airway that leads to inflammation and impairment of upper airway reflexes during sleep. This worsens any SDB even in the absence of aspiration. The aggressive treatment of GER must be initiated if present.
| Conclusion | | |
The progress has been made in our understanding of paediatric OSA, and we can now identify factors leading to its development or worsening.[22] However, a lot of general paediatricians are still unaware of these advances and of the treatment options available, particularly those addressing the risk-factors leading to increased risk of collapse of the upper-airway during sleep. The frequency of paediatric OSA can be significantly decreased if the basic functions such as nasal breathing, sucking, swallowing, masticating, and phonation were to be regularly investigated evaluated for appropriate development of upper-airway[23] and for early correction of abnormal development if present. Greater awareness by the paediatricians will lead to earlier diagnosis and treatment options for the parents.
Acknowledgements
The authors would like to thank Prof. Anne Goh and Dr. Daniel Kwok-Keung Ng for editing and polishing the manuscript. Some of researches were supported by Chang Gung Memorial Hospital Grant No: CRRPG5C0171, 172 and 173 to YS Huang.
Financial support and sponsorship
Nil.
Conflicts of interest
There are no conflicts of interest.
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