Heated humidified high flow nasal cannula therapy in children with obstructive sleep apnea: A randomized cross-over trial.

OBJECTIVE/BACKGROUND: Moderate-to-severe obstructive sleep apnea (OSA) is highly prevalent in children with obesity and/or underlying medical complexity. The first line of therapy, adenotonsillectomy (AT), does not cure OSA in more than 50% of these children. Consequently, continuous positive airway pressure (CPAP) is the main therapeutic option but adherence is often poor. A potential alternative which may be associated with greater adherence is heated high-flow nasal cannula (HFNC) therapy; however, its efficacy in children with OSA has not been systematically investigated. The study aimed to compare the efficacy of HFNC with CPAP to treat moderate-to-severe OSA with the primary outcome measuring the change from baseline in the mean obstructive apnea/hypopnea index (OAHI). PARTICIPANTS/METHODS: This was a single-blinded randomized, two period crossover trial conducted from March 2019 to December 2021 at a Canadian pediatric quaternary care hospital. Children aged 2-18 years with obesity and medical complexity diagnosed with moderate-to-severe OSA via overnight polysomnography and recommended CPAP therapy were included in the study. Following diagnostic polysomnography, each participant completed two further sleep studies; a HFNC titration study and a CPAP titration study (9 received HFNC first, and 9 received CPAP first) in a random 1:1 allocation order. RESULTS: Eighteen participants with a mean ± SD age of 11.9 ± 3.8 years and OAHI 23.1 ± 21.7 events/hour completed the study. The mean [95% CI] reductions in OAHI (-19.8[-29.2, -10.5] vs. -18.8 [-28.2, -9.4] events/hour, p = 0.9), nadir oxygen saturation (7.1[2.2, 11.9] vs. 8.4[3.5, 13.2], p = 0.8), oxygen desaturation index (-11.6[-21.0, -2.3] vs. -16.0[-25.3, -6.6], p = 0.5) and sleep efficiency (3.5[-4.8, 11.8] vs. 9.2[0.9, 15.5], p = 0.2) with HFNC and CPAP therapy were comparable between conditions. CONCLUSION: HFNC and CPAP therapy yield similar reductions in polysomnography quantified measures of OSA severity among children with obesity and medical complexities. TRIAL REGISTRATION: NCT05354401 ClinicalTrials.gov.

Chewing gum: alternative therapy to oxygen intolerance.

Rapid-onset obesity with hypothalamic dysregulation, hypoventilation, and autonomic dysregulation (ROHHAD) syndrome is a rare complex disorder associated with alterations in the endocrine system, autonomic nervous system, and respiratory system. Previously published case reports and studies have noted sleep-disordered breathing in patients with ROHHAD syndrome. Nocturnal respiratory manifestations, which if untreated early by respiratory support, may cause cardiorespiratory arrest and a life-threatening condition. More recently, it has been recognized that children with ROHHAD syndrome have central pauses during wakefulness associated with intermittent oxygen desaturations. We report novel findings of a child with ROHHAD syndrome displaying an irregular breathing pattern and significant central pauses associated with oxygen desaturations during wakefulness, whose respiratory status improved while chewing gum. This was used as an alternative to supplemental oxygen therapy. CITATION: Sunkonkit K, Selvadurai S, Yeh EA, Hamilton J, Narang I. Chewing gum: alternative therapy to oxygen intolerance. J Clin Sleep Med. 2022;18(6):1723-1726.

Incidence / predictors of pediatric obstructive sleep apnea with normal oximetry.

BACKGROUND: The polysomnogram (PSG) is the "gold standard" for diagnosing obstructive sleep apnea (OSA). However, nocturnal oximetry is a practical screening tool for children with adenotonsillar hypertrophy (ATH). This study aimed to investigate the incidence of, and predictive factors for, OSA in children with ATH and normal / inconclusive overnight oximetry. METHODS: The prospective study enrolled children aged 3-15 years with ATH and normal / inconclusive overnight oximetry. All participants underwent full-night PSG. To evaluate the predictors of OSA, we used logistic regression analysis, including sex, history of allergic rhinitis, body mass index z-score, neck circumference-height ratio, and polysomnographic parameters (obstructive apnea-hypopnea index (OAHI), nadir oxygen saturation (SpO2), peak end-tidal CO2 , and arousal index). RESULTS: The participants were 189 children; 167 (88%) were diagnosed with OSA by PSG. A history of allergic rhinitis (P = 0.033), and the PSG findings for nadir SpO2 (P = 0.027) and arousal index (P = <0.001) predicted the diagnosis of OSA. We divided patients with OSA into two groups (mild versus moderate to severe OSA). Patients with OAHI ≥5/h were defined as having moderate-to-severe OSA. No clinical factors significantly predicted OAHI ≥5. Of the 189 participants, 58 children (31%) were diagnosed with severe OSA (OAHI ≥10). The only PSG factor that predicted severe OSA was the arousal index (P < 0.001). CONCLUSIONS: The observed incidence of OSA in children aged 3-15 years with ATH and normal/inconclusive overnight oximetry was very high. A history of allergic rhinitis may help to triage the patients. The arousal index was a predictor of pediatric OSA.

A Novel GNAS Mutation Causing Isolated Infantile Cushing's Syndrome.

Infantile Cushing's syndrome is potentially found as part of McCune-Albright syndrome (MAS) which is caused by postzygotic somatic mutations of the GNAS gene. MAS is typically characterized by a triad of polyostotic fibrous dysplasia, café-au-lait skin pigmentation, and precocious puberty or other endocrine hyperfunction. Here, we describe a 2-month-old female infant with features of Cushing's syndrome without café au lait spots, polyostotic fibrous dysplasia, and clinical evidence of other endocrine hyperfunction. Investigations demonstrated adrenocorticotropic hormone-independent Cushing's syndrome with bilateral adrenal gland enlargement. Whole-exome sequencing of leukocytes identified a de novo heterozygous novel missense mutation (c.521G>A, p.Cys174Tyr) in the GNAS gene. The patient experienced clinical improvement of Cushing's syndrome during ketoconazole treatment. Her clinical course was complicated by Pneumocystis jiroveci pneumonia. She also had shortened activated partial thromboplastin time indicating a hypercoagulable state and resulting in pulmonary embolism. She eventually manifested gonadotropin-independent precocious puberty at the age of 13 months after ketoco-nazole was discontinued. This patient demonstrated that Cushing syndrome can be the presenting sign of MAS in infancy. A high index of suspicion followed by genetic analysis is essential in order to establish a diagnosis.

Urinary cysteinyl leukotriene E4 level and therapeutic response to montelukast in children with mild obstructive sleep apnea.

BACKGROUND: Antileukotriene has been used for alleviating disease severity in children with adenotonsillar hypertrophy (ATH) and mild obstructive sleep apnea (OSA). Previous study showed the relationship between urinary cysteinyl leukotriene E4 (uLTE4) level and therapeutic response to montelukast in asthmatic adults. However, this relationship has never been investigated in pediatric OSA. OBJECTIVES: To determine the relationship between uLTE4 level and therapeutic response to montelukast in children with ATH and mild OSA. METHODS: Children aged 3-15 yrs who had ATH and mild OSA were enrolled. All had quality of life (assessed by Thai version OSA-18 QoL questionnaire) and uLTE4 levels measured prior to start a 6-week course of montelukast treatment. Overnight polysomnography (PSG) and QoL reassessment were performed after completing the treatment. Those who demonstrated a large improvement of mean total QoL score or ≥ 50% decrease of obstructive apnea-hypopnea index (OAHI) after the treatment were defined as responders. RESULTS: Twenty-six children were enrolled (mean age 7.5 ± 2.9 yrs, 38.5% male). After 6-week course of montelukast, nine (34.6%) children showed significant improvement. The mean uLTE4 level from the responders was higher comparing to the non-responders (2,952.56 ± 966.9 vs. 978.6 ± 460.8 pg/mg creatinine; p < 0.001). uLTE4 level of ≥ 1,457 pg/mg creatinine had 100% sensitivity and 88.2% specificity in identifying the responders. CONCLUSIONS: We found the association between ULTE4 and therapeutic response to monteleukast. The uLTE4 level of ≥ 1,457 pg/mg creatinine could predict the therapeutic response to montelukast in children who had ATH and mild OSA.