Australasian Sleep Association clinical practice guidelines for performing sleep studies in children

Can postural changes in spirometry in children with Duchenne muscular dystrophy predict sleep hypoventilation?

AIM

To explore the relationship between postural changes in lung function and polysomnography (PSG) in children with Duchenne muscular dystrophy (DMD).

METHODS

In this prospective cross-sectional study, children with DMD performed spirometry in sitting and supine positions. A control group of age and gender matched healthy children also underwent postural lung function testing. PSG was performed within six months of spirometry.

RESULTS

Seventeen children with DMD, aged 12.3 ± 3 years performed sitting spirometry. 14 (84%) performed acceptable spirometry in the supine position. Mean FEV1sit and FVCsit were 77% (SD ± 22) and 74% (SD ± 20.4) respectively, with mean% ΔFVC(sit-sup) 9% (SD ± 11) (range 2% to 20%), and was significantly greater than healthy controls 4% (n = 30, SD ± 3, P < 0.001). PSG data on the 14 DMD children with acceptable supine spirometry showed total AHI 6.9 ± 5.9/hour (0.3 to 29), obstructive AHI 5.2 ± 4.0/hour (0.2 to 10), and REM AHI 14.1 ± -5.3/hour (0.1 to 34.7). ΔFVC(sit-sup) had poor correlation with hypoventilation on polysomnography.

CONCLUSION

Children with DMD and mild restrictive lung disease showed greater postural changes in spirometry than healthy controls but lower supine spirometry was not predictive of sleep hypoventilation.

Demonstration of Accuracy and Feasibility of Remotely Delivered Oximetry: A Blinded, Controlled, Real-World Study of Regional/Rural Children with Obstructive Sleep Apnoea

Objectives: Evaluate diagnostic accuracy and feasibility of a mail-out home oximetry kit. Design: Patients were referred for both the tertiary/quaternary-centre hospital-delivered oximetry (HDO) and for the mail-out remotely-delivered oximetry (RDO). Quantitative and qualitative data were collected. The COVID-19 pandemic began during this study; therefore, necessary methodological adjustments were implemented. Setting: Patients were first evaluated in Swan Hill, Victoria. RDO kits were sent to home addresses. For the HDO, patients travelled to the Melbourne city area, received the kit, stayed overnight, and returned the kit the following morning. Participants: All consecutive paediatric patients (aged 2−18), diagnosed by a specialist in Swan Hill with obstructive sleep apnoea (OSA) on history/examination, and booked for tonsillectomy +/− adenoidectomy, were recruited. Main outcome measures: Diagnostic accuracy (i.e., comparison of RDO to HDO results) and test delivery time (i.e., days from consent signature to oximetry delivery) were recorded. Patient travel distances for HDO collection were calculated using home/delivery address postcodes and Google® Maps data. Qualitative data were collected with two digital follow-up surveys. Results: All 32 patients that had both the HDO and RDO had identical oximetry results. The HDO mean delivery time was 87.7 days, while the RDO mean delivery time was 23.6 days (p value: <0.001). Qualitatively, 3/28 preferred the HDO, while 25/28 preferred the RDO (n = 28). Conclusions: The remote option is as accurate as the hospital option, strongly preferred by patients, more rapidly completed, and also an ideal investigation delivery method during certain emergencies, such as the COVID-19 pandemic.

Comparison of polysomnographic characteristics between low birthweight and normal birthweight children in the Northern Territory of Australia: A case-control study

OBJECTIVES

To describe the sleep architecture of pediatric patients according to whether they were born low birthweight (birthweight <2500 g, LBW) or normal birthweight (birthweight >2500 g).

DESIGN

Case control study.

SETTING

Pediatric sleep laboratory in the Northern Territory of Australia during a 5-year study period (2015- 2020).

PARTICIPANTS

Pediatric patients (aged <18 years) referred to the specialist sleep service for assessment of clinically suspected sleep disorders.

MEASUREMENTS

Sleep onset latency, rapid eye movement (REM) sleep latency, wake time after sleep onset, total sleep time, sleep efficiency, non-rapid eye movement stages N1/N2/N3, and REM sleep duration, total/spontaneous/respiratory/limb related arousal indexes, total/non-rapid eye movement/REM obstructive apnea-hypopnea index and oxygen saturation.

RESULTS

One hundred and seventy-two pediatric patients had birthweight data available of whom 19 were LBW. LBW patients showed significantly greater sleep disruption and higher prevalence of poor sleepers (<80% efficiency). In multivariate regression models, increasing birthweight was associated with significantly greater sleep efficiency and total sleep time. After accounting for gestational age LBW was associated with increased odds of obstructive sleep apnea.

CONCLUSIONS

Among pediatric patients LBW is associated with increased sleep disruption and reduced sleep efficiency. This is attenuated by gestational age, though both gestational age and LBW significantly influence odds of obstructive sleep apnea. This sleep health deficit may contribute to development of chronic disease in this vulnerable population, and should be monitored to provide avenues for early intervention.

Daytime predictors of nocturnal hypercapnic hypoventilation in children with neuromuscular disorders

OBJECTIVES

To examine objective daytime predictors of nocturnal hypercapnic hypoventilation (NHH) and identify a forced vital capacity (FVC) z-score cut off that predicts NHH using the 2012 Global Lung Function Initiative (GLI) reference equations in pediatric neuromuscular patients.

DESIGN

Single-centre retrospective medical record review.

SETTING

Tertiary pediatric hospital in Australia.

PATIENTS

Children (<18 years old) with a neuromuscular disorder (NMD) who had a diagnostic sleep study over a 5-year period.

RESULTS

Fifty children were included, median age 11.9 years (interquartile range [IQR]: 4.5-14.3). The majority of children had a diagnosis of Duchenne Muscular Dystrophy (32%). NHH was diagnosed in 18 children (36%). Multivariate logistic regression analysis performed for the entire cohort confirmed a statistically significant association between NHH and scoliosis (odds ratio [OR]: 3.3, p = 0.03), but not age (OR: 1.01, p = 0.26), body mass index z-score (OR: 0.86, p = 0.26) or use of a wheelchair for mobility (OR: 1.25, p = 0.72). For the subset of 29 children who had spirometry testing (median age 12.9 years [IQR: 10.2-14.3]), FVC z-score was the only statistically significant predictor of NHH (OR: 0.45, p = 0.02). NHH was predicted by an FVC z-score <-3.24 (sensitivity 78%, specificity 73%), or FVC <60% predicted (sensitivity 78%, specificity 73%). There was a strong positive correlation between FVC and forced expiratory volume in 1 s z-scores (r_p  = 0.98, p = 0.00) and FVC and peak expiratory flow  z-scores (r_p  = 0.72, p = 0.00).

CONCLUSION

Children with a NMD and scoliosis or a lower FVC z-score have increased odds of having NHH.

Telehealth-supported level 2 pediatric home polysomnography

STUDY OBJECTIVES

The gold standard for diagnosis of pediatric obstructive sleep apnea is level 1 polysomnography (PSG). Some children are selected for unattended level 2 home sleep apnea testing (HSAT) with telehealth support, and we sought to review this home service.

METHODS

A retrospective audit was conducted from 2013 to 2020. All level 2 HSAT reports in children aged 5-18 years referred for suspected OSA were analyzed. American Academy of Sleep Medicine compliant portable PSG acquisition equipment with EEG was used. The primary outcome was the proportion of technically successful tests achieved, and of these the % with potential underestimation of diagnostic category. Secondary outcomes included sleep quality and parental acceptance by non-validated service-specific questionnaire. Data were analyzed using descriptive & inferential statistics. χ² tests were used for categorical variables.

RESULTS

There were 233 (139 male, 59.6%) patients studied between 2013 and 2020 (7 years). The mean age was 10.8 (SD 3.6) years. 67 patients (28.8%) had comorbidities. Technically successful studies were obtained in almost 90% (209/233) and failed studies occurred in just over 10% (24/233). One failed study still achieved a diagnosis. There was no significant difference between failed studies set up by HITH nurses compared with Sleep scientists (p=0.2). Overall, an accurate diagnosis was made in 80% (167/209) of patients, with potential for under-estimation in 20% (42/209). Six hours or more of sleep was obtained in 89.5%. Parental questionnaires revealed 89.3% perceived high-level care, 91% perceived increased convenience and 76% good/excellent telehealth support.

CONCLUSIONS

Telehealth-supported pediatric HSAT achieves technical success in almost 90% of patients investigated for OSA, with 89.5% achieving ≥6 hours sleep duration, and excellent family acceptability.

Disruptive Therapy Using a Nonsurgical Orthodontic Airway Plate for the Management of Neonatal Robin Sequence: 1-Year Follow-up

We recently published the 3-month follow-up of 2 neonates with Robin sequence whose mandibular hypoplasia and restricted airway were successfully treated with an orthodontic airway plate (OAP) without surgical intervention. Both infants were successfully weaned off the OAP after several months of continuous use. We present the course of OAP treatment in these patients with a focus on breathing, feeding, and facial growth during their first year of life. Both infants demonstrated stable mandibular projection, resolution of obstructive sleep apnea, and normal development.

Home (Level 2) polysomnography is feasible in children with suspected sleep disorders

AIM

To audit the feasibility and patient experience of home polysomnography (sleep study) for the investigation of a sleep disorder in children.

METHODS

The signal quality and outcomes of a Level 2 (home) polysomnography in young people undergoing investigation between September 2020 and January 2021 in a single centre was reviewed. A successful home polysomnogram was defined as a study with ≥6 h of sleep and all channels (EEG, thoraco-abdominal bands, calculated airflow, and pulse oximetry) present for at least 90% of the study time. Feedback from the guardian and young person was collected following the study using a questionnaire.

RESULTS

Fifty-five patients, aged 4 months to 18 years, were included. A successful polysomnogram, on the first attempt, was achieved for 48/55 (87%) subjects. There were no differences in success when accounting for neurodevelopmental conditions, OSA severity or age. The majority (76%) of guardians felt that their child slept the same or better than normal and only 12% found having the study conducted at home difficult. Following the study, only 8% would have preferred a hospital sleep study in retrospect.

CONCLUSIONS

Home polysomnography produced a technically adequate study for the majority of subjects. Most families also found the experience of having a home sleep study to be positive. These data support the use of home sleep studies as an alternative to an in-patient sleep study, in appropriate circumstances, for young people undergoing investigation of a sleep disorder.

Objective measurements for upper airway obstruction in infants with Robin sequence: what are we measuring? A systematic review

STUDY OBJECTIVES

Identifying optimal treatment for infants with Robin sequence (RS) is challenging due to substantial variability in the presentation of upper airway obstruction (UAO) in this population. Objective assessments of UAO and treatments are not standardized. A systematic review of objective measures of UAO was conducted as step towards evidence based clinical decision making for RS.

METHODS

A literature search was performed in Pubmed and Embase databases (1990-2020) following PRISMA-guidelines. Articles reporting on RS and UAO-treatment were included if the following objective measures were studied: oximetry, polysomnography and blood gas. Quality was appraised by methodological index for non-randomized studies (MINORS, range:0-24).

RESULTS

A total of 91 articles met inclusion criteria. Mean MINORS-score was 7.1 (range:3-14). Polysomnography was most frequently used (76%) followed by oximetry (20%) and blood gas (11%). Sleep position of the infant was reported in 35% of studies, with supine position most frequently, and monitoring time in 42%, including overnight recordings in more than half. Of 71 studies that evaluated UAO-interventions, the majority used polysomnography (90%), of which 61% did not specify the polysomnography technique. Reported polysomnography metrics included oxygen saturation (61%), apnea-hypopnea index (52%), carbon dioxide levels (31%), obstructive-apnea-hypopnea index (27%), and oxygen-desaturation-index (16%). Only 42 studies reported indications for UAO-intervention, with oximetry and polysomnography thresholds used equally (both 40%). In total, 34 distinct indications for treatment were identified.

CONCLUSIONS

This systematic review demonstrates a lack of standardization, interpretation and reporting of assessment and treatment indications for UAO in RS. An international, multidisciplinary consensus protocol is needed to guide clinicians on optimal UAO assessment in RS.

Paediatrics: how to manage obstructive sleep apnoea syndrome

Obstructive sleep apnoea syndrome (OSAS) is defined as the intermittent reduction or cessation of airflow due to partial or complete obstruction of the upper airway during sleep. Paediatric OSAS has specific contributing factors, presenting symptoms and management strategies in various age groups. Untreated OSAS can lead to detrimental effects on neurocognitive development and cardiovascular and metabolic functions of a growing child. In the past decade, practice guidelines have been developed to guide the evaluation and management of OSAS. This article provides a narrative review on the current diagnostic and treatment options for paediatric OSAS. Alternative diagnostic tools other than the standard polysomnography are discussed. Adenotonsillectomy is considered the first-line therapy yet it is not suitable for treatment of all OSAS cases. Nocturnal non-invasive positive airway pressure ventilation is effective and could be the priority treatment for patients with complex comorbidities, residual OSAS post-adenotonsillectomy or obesity. However, intolerance and non-adherence are major challenges of positive airway pressure therapy especially in young children. There is increasing evidence for watchful waiting and other gentler alternative treatment options in mild OSAS. The role of anti-inflammatory drugs as the primary or adjunctive treatment is discussed. Other treatment options, including weight reduction, orthodontic procedures and myofunctional therapy, are indicated for selected patients. Nevertheless, the successful management of paediatric OSAS often requires a multidisciplinary team approach.

Preoperative identification of children at high risk of obstructive sleep apnea

Obstructive sleep apnea is a common childhood disorder which can lead to serious health problems if left untreated. Enlarged adenoid and tonsils are the commonest causes, and adenotonsillectomy is the recommended first line of treatment. Obstructive sleep apnea poses as an anesthetic challenge, and it is a well-known risk factor for perioperative adverse events. The presence and severity of an obstructive sleep apnea diagnosis will influence anesthesia, pain management, and level of monitoring in recovery period. Preoperative obstructive sleep apnea assessment is necessary, and anesthetists are ideally placed to do so. Currently, there is no standardized approach to the best method of preoperative screening for obstructive sleep apnea. Focused history, clinical assessments, and knowledge regarding the strengths and limitations of available obstructive sleep apnea assessment tools will help recognize a child with obstructive sleep apnea in the preoperative setting.

Use of non-invasive ventilation in children with congenital tracheal stenosis

INTRODUCTION

Congenital tracheal stenosis (CTS) is a rare airway condition characterized by complete tracheal rings. Most patients undergo a slide tracheoplasty, which greatly reduces mortality but significant morbidity remains. The assessment of sleep disordered breathing (SDB) and use of non-invasive ventilation (NIV) in these children has not been described.

AIM

To describe the presence of SDB and use of NIV in children diagnosed with CTS over a 10-year period (2005-2015).

DESIGN

Retrospective case series at a tertiary children's hospital.

RESULTS

There were 16 patients identified with CTS with a median [range] age at diagnosis of 2.5 months (0-9 months). One child died in the immediate post-operative period following a slide tracheoplasty, leaving 15 survivors. There were no later deaths during follow-up while using NIV for up to 3 years after surgery. Slide tracheoplasty was undertaken in (12/15) with long-segment tracheal stenosis. 3/15 patients had a short-segment tracheal stenosis and were managed conservatively. The use of NIV occurred in 10/15 (66.67%) patients, all of whom had long-segment CTS. Pre-operative polysomnography (PSG) showed a median (±SD) obstructive apnoea/hypopnoea index (OAHI) of 14.6/hr (±6.2) which reduced to 7.2/hour (±4.2) on NIV prior to slide tracheoplasty. The median oxygen desaturation index (ODI) before NIV use was 15.3 (±19.4) episodes/hour, which reduced to 6.3 (±11) on NIV. The median period of NIV use was 5 [1-24 months] months.

CONCLUSION

Patients with CTS have obstructed sleep disordered breathing. Trials of NIV are well-tolerated and improve sleep disordered breathing.