Introduction There is limited data available that describe the pattern of change in severity of airway obstruction and treatment requirements of infants with Robin sequence (RS). Methods We undertook retrospective review of 3 infants with RS and severe OSA who were treated with CPAP in early infancy. All were managed at the Children’s Hospital at Westmead. Interval CPAP pressure requirements, sleep screening studies and PSG data were reviewed and obstructive apnoea-hypopnea index (OAHI), oxygen desaturation index (ODI), along with percentage of time <90% oxygen saturation were obtained. Results: For two patients, an early increase in CPAP pressure was observed with peak pressure reached at 5 weeks and 7 weeks, respectively, followed by reduction of pressure requirements and cessation of therapy at age 39 weeks for Patient 1 & 74 weeks for Patient 2. By way of contrast, the clinical course of a 3rd patient included jaw distraction at 17 weeks age, time off CPAP, a requirement to recommence CPAP at 21 weeks, and trials of other therapy, but treatment was eventually ceased at 75 weeks. Apnoea indices on PSG did not reflect the CPAP pressure requirements for any of the infants. Conclusions: Our data suggests a trend toward early increases in CPAP pressure requirements in typical infants with RS, before a decrease and cessation later in infancy. The rate at which this occurs may reflect the underlying severity of obstruction. Further research could help confirm this pattern. KEYWORDS Robin sequence, OSA, CPAP, polysomnography, OAHI, ODI, jaw distraction

Aim To explore the relationship between postural changes in lung function and polysomnography (PSG) in the assessment of early sleep disordered breathing in children with neuromuscular disorders [NMD]. Methods In this prospective cross-sectional study, children with NMD performed spirometry in sitting (si) and supine (su) positions. A control group of age and gender matched healthy children also underwent postural lung function testing. PSG was performed within 6 months of spirometry. Spirometry was acceptable according to ATS standards and PSGs scored according to AASM guidelines. Results Forty-one children with NMD, aged 12.3 ±3 years (21 males) performed sitting spirometry. Thirty [73%] performed acceptable spirometry in the supine position. Underlying diagnoses were heterogeneous, with the majority having Duchenne Muscular Dystrophy (n=17). Mean FEV1sit and FVCsit were 78% (SD ±22) and 75% (SD±20.4) respectively, with mean% ΔFVC (sit – sup) 9±11% (range 2% to 20%), and was significantly greater than healthy controls (n=30 SD ±3) (p<0.001). PSG data on these 30 children showed total AHI 6.9 ±5.9/hr (0.3 to 29), obstructive AHI 5.2±4.0/hr (0.2 to 10), and REM AHI 14.1+/-5.3/hr (0.1 to 34.7). A moderate correlation was present between supine FVC% and AHI (r=0.62, p=0.001) in those not using non-invasive ventilation [NIV] in sleep [N=22] but not with the rise in CO2 from non-REM to REM sleep (6 ±1.9 mmHg, range 4 to 11). Conclusion Children with NMD and mild restrictive lung disease showed greater postural changes in spirometry than healthy controls, with changes being greatest in children who required nocturnal NIV.

Summary. Objectives: After corrective for scoliosis, postoperative pulmonary complications lead to increases in morbidity, length of hospital stay and mortality. This study aimed to identify associations with such respiratory complications. Methods: This retrospective cohort study included all children aged ≤17 years who underwent spinal surgery for scoliosis between January 2009 and January 2012 at a quaternary paediatric hospital. Factors associated with severely compromised pulmonary function (SCPF) were established and correlations with the occurrence of postoperative pulmonary complications and length of hospital stay (LOS) were identified. Rresults: Altogether, 133 children had corrective surgery for scoliosis, aged 12.7 (range 2-17) years at operation. Scoliosis causes were identified as: idiopathic (39.8%), neuromuscular disease (32.2%), syndrome (15.7%) and congenital (12%). Correlates with SCPF (FVC<40% predicted, n=10) included markers of sleep hypoventilation, including serum bicarbonate ≥29 mmol/L, morning pCO2 >50 mmHg (P=0.003), and overnight, episodic CO2 retention of >7 mmHg, thus an additional 8 children with SCPF were identified. Post-operative pulmonary complications were seen in 24 children (18%) and their occurrence correlated with higher Cobb angle (>90°), lower pulmonary function (FVC), higher serum bicarbonate and underlying neuromuscular disease. Amongst 18 children with SCPF, regular use of NIV pre-operatively was associated with reduced rate of post-operative pulmonary complications (P =0.02) and reduced LOS by 6.4 days (P =0.01). Conclusion: Nocturnal hypoventilation identifies children with SCPF. Use of NIV in children with SCPF was linked to fewer post-operative pulmonary complications and reduced duration of hospital stay. Keywords: Ventilation ; Pulmonary complications ; Scoliosis ; Polysomnography.