Sleep-related breathing disorders in infants with spina bifida repaired prenatally and postnatally.

STUDY OBJECTIVES: Advances in prenatal repair of myelomeningocele (MMC) have improved outcomes involving different organ systems. There is limited data on respiratory outcomes following prenatal surgical repair. We hypothesize there is no difference in respiratory outcomes between spina bifida (SB) patients who have undergone prenatal versus postnatal repair. METHODS: We performed a retrospective study of 46 infants <1 year with SB seen at Children's Hospital Los Angeles from 2004-2022. Demographic data, timing of closure, neonatal course, Chiari II malformation (CIIM), ventriculoperitoneal shunt (VPS), polysomnography (PSG) results, and need for supplemental oxygen were collected. Unpaired t-test and Chi-square Test were used to analyze results. RESULTS: 31/46 had prenatal repair of MMC; average age at repair was 27 weeks post-conception (PCA). Average age at postnatal repair was 37 PCA. There was no difference in age at PSG. There was no difference in CIIM presence (p=0.61). 60% of patients with postnatal repair and 23% in the prenatal group underwent VPS placement (p=0.01).There was no difference in PSG findings between the two groups: CAI (p=0.11), OAHI (p=0.64), average SpO2 baseline (p=0.91), average SpO2 nadir (p=0.17), average PETCO2 baseline (p=0.87), and average PETCO2 maximum (p=0.54). There were no significant differences in the proportion of patients on supplemental O2 (p=0.25), CSA or OSA between groups. CONCLUSIONS: Patients with SB who've undergone closure of neural tube defect have persistent central apneas, obstructive apneas, and significant hypoxemia. There were no differences in the frequency or severity of sleep-disordered breathing in those with prenatal repair versus postnatal repair.

Prevalence of pulmonary hypertension on echocardiogram in children with severe obstructive sleep apnea.

STUDY OBJECTIVES: Pulmonary hypertension (PH) is a rare yet serious complication of obstructive sleep apnea (OSA). Echocardiographic screening for PH is recommended in children with severe OSA, but the health care burden of universal screening is high. We sought to determine the prevalence of PH on echocardiogram among children with severe OSA and identify variables associated with a positive PH screen. METHODS: Retrospective study of 318 children with severe OSA (obstructive apnea-hypopnea index ≥ 10 events/h) and echocardiogram within 1 year of polysomnogram. PH-positive echocardiogram was defined by peak tricuspid regurgitation velocity ≥ 2.5 m/s and/or 2 or more right-heart abnormalities suggestive of elevated pulmonary artery pressure. Patient characteristics and polysomnogram data were compared to identify factors associated with PH. RESULTS: Twenty-six children (8.2%; 95% confidence interval [CI] 5.4-11.8%) had echocardiographic evidence of PH. There was no difference in age, sex, body mass index, obstructive apnea-hypopnea index, or oxygenation indices between patients with and without PH. Sleep-related hypoventilation (end-tidal CO2 > 50 mmHg for > 25% of total sleep time) was present in 25% of children with PH compared with 6.3% of children without PH (adjusted prevalence ratio = 2.73; 95% CI 1.18-6.35). Forty-six percent of children (12/26) with PH had Down syndrome vs 14% (41/292) without PH (adjusted prevalence ratio = 3.11; 95% CI 1.46-6.65). CONCLUSIONS: There was a relatively high prevalence of PH on echocardiogram in our cohort of children with severe OSA. The findings of increased PH prevalence among children with sleep-related hypoventilation or Down syndrome may help inform the development of targeted screening recommendations for specific pediatric OSA populations. CITATION: Maloney MA, Davidson Ward SL, Su JA, et al. Prevalence of pulmonary hypertension on echocardiogram in children with severe obstructive sleep apnea. J Clin Sleep Med. 2022;18(6):1629-1637.

Children with Congenital Central Hypoventilation Syndrome Do Not Wake up to Ventilator Alarms.

PURPOSE: Congenital Central Hypoventilation Syndrome (CCHS) requires lifelong ventilatory support during sleep. Subjects with CCHS are vulnerable to sleep disturbances associated with treatments, monitoring alarms, and care they receive. We hypothesized that sleep would be disrupted in patients  with CCHS due to ventilatory support and other treatments at night. METHODS: An anonymous survey of patients with CCHS, age up to 17 years was conducted through REDCAP. Subjects were recruited in person, by flyer, email, and social media. Data collected included demographics, PHOX2B genotype, ventilatory support, treatments, nursing, and sleep parameters. RESULTS: We received 23 responses (35% female, 8.1 years ± 5.6). PHOX2B genotypes were 20/24 PARM (2), 20/25 PARM (4), 20/26 PARM (2), 20/27 PARM (9), ≥ 20/28 PARM (2), and NPARM (2). Two subjects did not indicate the PHOX2B genotype. 13/23 were ventilated by PPV via tracheostomy, 7 by NIPPV, 2 by diaphragm pacing, and 1 did not indicate. Additional treatments received at night included suctioning (9), aerosol (1), G-tube feeding (2), and none (11). Only 9 received nursing at night. 13 used pulse oximetry for monitoring, and 9 used both pulse oximetry and end tidal CO2 monitor. 17/23 rarely woke up due to ventilator or monitor alarms. 11/23 usually or sometimes woke up at least once a night; only 2/11 woke up due to alarms. 5/17 who rarely woke up to the alarms had night nursing. CONCLUSION: Most subjects with CCHS did not awaken to ventilator or monitoring alarms and a majority of these patients did not have nighttime nursing. (Mathur et al. in Sleep 43(Supplement_1):A333, 2020).

Evaluation of Obstructive Sleep Apnea in Prone Versus Nonprone Body Positioning With Polysomnography in Infants With Robin Sequence.

OBJECTIVE: Management of obstructive sleep apnea in infants with Robin sequence (RS) includes prone positioning during sleep, which conflicts with safe infant sleep data. We examined changes in polysomnography (PSG) parameters for prone versus nonprone body positions in these infants. DESIGN: Pre-post interventional, nonblinded study. PARTICIPANTS: Infants with RS referred for PSG were recruited from craniofacial clinic and inpatient units at Children's Hospital Los Angeles, a tertiary pediatric center. Fourteen infants were recruited, and 12 studies were completed on both body positions; 11 studies were used in the analysis. INTERVENTIONS: The PSG was divided into nonprone and prone sleep, moving from their usual sleep position to the other position midway in the study. MAIN OUTCOME MEASURES: Data was collected in each position for obstructive apnea-hypopnea index (oAHI), central apnea index (CAI), sleep efficiency (SE), and arousal index (AI). Signed rank test was used to evaluate the change in body position. RESULTS: All infants were term except 1, age 7 to 218 days (mean: 55 days; standard deviation: 58 days), and 8 (57%) of 14 were female. From nonprone to prone sleep position, the median oAHI (16.0-14.0), CAI (2.9-1.0), and AI (28.0-19.9) decreased (P = .065); SE increased (67.4-85.2; P = .227). CONCLUSIONS: Prone positioning may benefit some infants with RS. However, even those with significant improvement in obstructive sleep apnea did not completely resolve their obstruction. The decision to use prone positioning as a therapy should be objectively evaluated in individual infants.

Rapid Response and Code Events in Hospitalized Children on Home Mechanical Ventilation.

BACKGROUND: There is limited knowledge of rapid-response (RR) events and code events for children receiving home mechanical ventilation (HMV) via a tracheostomy in a non-ICU respiratory care unit. The purpose of this study was to describe the demographic and clinical factors leading to deterioration among these children and to identify the incidence and outcomes following rapid-response and code events. METHODS: A retrospective review was conducted on hospitalized HMV children who had RR/code events in a non-ICU respiratory care unit. RESULTS: There were a total of 50 RR events, and the primary clinical problem was acute respiratory distress, with 27 subjects (54%) needing ventilator adjustments. Twenty (40%) RR events occurred among children who were awaiting initial home discharge. Of 18 total code events, 7 (39%) children needed a tracheostomy-related intervention. There were 10 (56%) codes among children on mechanical ventilation awaiting initial home discharge. Children on HMV had 8.73 RR events per 1,000 patient days, whereas all other hospitalized children had 4.61 RR events per 1,000 patient days. In addition, children on HMV had 3.14 codes per 1,000 patient days, whereas all other hospitalized children had 0.74 codes per 1,000 patient days. All children were discharged from the hospital, and no deaths were associated with RR/code events for the index hospitalization. CONCLUSIONS: The overall incidence of RR/code events in children on HMV was higher than among non-HMV hospitalized children. Children on HMV preparing for their initial hospital discharge had the greatest number of RR/code events. The most prevalent interventions among children with RR events were ventilator setting adjustments, and among children with codes the most frequent actions were tracheostomy-related interventions. Developing strategies to predict risk factors for RR/code events may help decrease harm among children on HMV.

Dynamic 3-D MR Visualization and Detection of Upper Airway Obstruction During Sleep Using Region-Growing Segmentation.

GOAL: We demonstrate a novel and robust approach for visualization of upper airway dynamics and detection of obstructive events from dynamic 3-D magnetic resonance imaging (MRI) scans of the pharyngeal airway. METHODS: This approach uses 3-D region growing, where the operator selects a region of interest that includes the pharyngeal airway, places two seeds in the patent airway, and determines a threshold for the first frame. RESULTS: This approach required 5 s/frame of CPU time compared to 10 min/frame of operator time for manual segmentation. It compared well with manual segmentation, resulting in Dice Coefficients of 0.84 to 0.94, whereas the Dice Coefficients for two manual segmentations by the same observer were 0.89 to 0.97. It was also able to automatically detect 83% of collapse events. CONCLUSION: Use of this simple semiautomated segmentation approach improves the workflow of novel dynamic MRI studies of the pharyngeal airway and enables visualization and detection of obstructive events. SIGNIFICANCE: Obstructive sleep apnea (OSA) is a significant public health issue affecting 4-9% of adults and 2% of children. Recently, 3-D dynamic MRI of the upper airway has been demonstrated during natural sleep, with sufficient spatiotemporal resolution to noninvasively study patterns of airway obstruction in young adults with OSA. This study makes it practical to analyze these long scans and visualize important factors in an MRI sleep study, such as the time, site, and extent of airway collapse.

Real-time 3D magnetic resonance imaging of the pharyngeal airway in sleep apnea.

PURPOSE: To investigate the feasibility of real-time 3D magnetic resonance imaging (MRI) with simultaneous recording of physiological signals for identifying sites of airway obstruction during natural sleep in pediatric patients with sleep-disordered breathing. METHODS: Experiments were performed using a three-dimensional Fourier transformation (3DFT) gradient echo sequence with prospective undersampling based on golden-angle radial spokes, and L1-norm regularized iterative self-consistent parallel imaging (L1-SPIRiT) reconstruction. This technique was demonstrated in three healthy adult volunteers and five pediatric patients with sleep-disordered breathing. External airway occlusion was used to induce partial collapse of the upper airway on inspiration and test the effectiveness of the proposed imaging method. Apneic events were identified using information available from synchronized recording of mask pressure and respiratory effort. RESULTS: Acceptable image quality was obtained in seven of eight subjects. Temporary airway collapse induced via inspiratory loading was successfully imaged in all three volunteers, with average airway volume reductions of 63.3%, 52.5%, and 33.7%. Central apneic events and associated airway narrowing/closure were identified in two pediatric patients. During central apneic events, airway obstruction was observed in the retropalatal region in one pediatric patient. CONCLUSION: Real-time 3D MRI of the pharyngeal airway with synchronized recording of physiological signals is feasible and may provide valuable information about the sites and nature of airway narrowing/collapse during natural sleep.

Vallecular cyst as a cause of obstructive sleep apnea in an infant.

A 3-month-old baby was diagnosed with obstructive sleep apnea (OSA) on polysomnography (PSG) with a high apnea hypopnea index (AHI). On further investigations he was found to have a vallecular cyst that was successfully treated. We discuss the clinical presentation of vallecular cysts and the importance of polysomnography in identifying this rare condition.

Development and growth of a large multispecialty certification examination: sleep medicine certification--results of the first three examinations.

This paper summarizes the results of the first three examinations (2007, 2009, and 2011) of the Sleep Medicine Certification Examination, administered by its six sponsoring American Board of Medical Specialty Boards. There were 2,913 candidates who took the 2011 examination through one of three pathways-self-attested practice experience, previous certification by the American Board of Sleep Medicine, or formal Sleep Medicine fellowship training. The 2011 exam was the last administration in which candidates who had not previously been admitted could take it without completion of formal Sleep Medicine fellowship training. As expected, the number of candidates admitted to the 2011 examination through the practice experience pathway increased, and the overall scores of these candidates were on average lower than the other candidates. Consequently, the pass rate for all first takers of the 2011 examination (65%) was lower than that observed from the 2009 examination (78%) and the 2007 examination (73%). For each administration, candidates admitted through the fellowship training pathway scored the highest; over 90% of them passed the 2011 and 2009 examinations.

Hospital readmissions for newly discharged pediatric home mechanical ventilation patients.

BACKGROUND: Ventilator-dependent children have complex chronic conditions that put them at risk for acute illness and repeated hospitalizations. OBJECTIVES: To determine the 12-month incidence of and risk factors for non-elective readmission in children with chronic respiratory failure (CRF) after initiation on home mechanical ventilation (HMV) via tracheostomy. METHODS: A retrospective cohort study of 109 HMV patients initiated and followed at an university-affiliated children's hospital between 2003 and 2009. Patient characteristics are presented using descriptive statistics; generalized estimated equations are used to estimate adjusted odds ratios of select predictor variables for readmission. RESULTS: The 12-month incidence of non-elective readmission was 40%. Close to half of these readmissions occurred within the first 3 months post-index discharge. Pneumonia and tracheitis were the most common reasons for readmission; 64% were pulmonary- or tracheostomy-related. Most demographic and clinical patient characteristics were not statistically associated with non-elective readmissions. Although, a change in the child's management within 7 days before discharge was associated readmissions shortly after index discharge. CONCLUSION: Non-elective readmissions of newly initiated pediatric HMV patients were common and likely multifactorial. Many of these readmissions were airway-related, and some may have been potentially preventable.

Longitudinal assessment of hemoglobin oxygen saturation in preterm and term infants in the first six months of life.

OBJECTIVE: To report longitudinal home recordings of hemoglobin O(2) saturation by pulse oximetry (Spo(2)) during unperturbed sleep in preterm and term infants. STUDY DESIGN: We recorded continuous pulse oximetry during the first 3 minutes of each hour of monitor use (nonevent epochs) for 103 preterm infants born at <1750 g and ≤ 34 weeks postmenstrual age (PMA), and 99 healthy term infants. RESULTS: Median baseline Spo(2) was approximately 98% for both the preterm and term groups. Episodes of intermittent hypoxemia occurred in 74% of preterm and 62% of term infants. Among infants with intermittent hypoxemia, the number of seconds/hour of monitoring <90% Spo(2) was initially significantly greater in the preterm than the term group and declined with age at a similar rate in both groups. The 75(th) to 95(th) percentiles for seconds/hour of Spo(2) <90% in preterm infants were highest at 36 weeks PMA and progressively decreased until 44 weeks PMA, after which time they did not differ from term infants. CONCLUSIONS: Clinically inapparent intermittent hypoxemia occurs in epochs unperturbed by and temporally unrelated to apnea or bradycardia events, especially in preterm infants at 36 to 44 weeks PMA.

Congenital hypoventilation syndromes.

Although rare, congenital hypoventilation syndromes profoundly impact affected patients and families. In some diseases, such as congenital central hypoventilation syndrome (CCHS), hypoventilation is a key presenting feature. Ventilatory abnormalities may not be immediately evident in other disease states. The clinical aspects of several pediatric hypoventilation syndromes, including CCHS, Chiari type II malformation, Prader-Willi syndrome, familial dysautonomia, and rapid onset obesity with hypothalamic dysfunction, hypoventilation, and autonomic dysregulation are presented.

Development and results of the first ABMS subspecialty Certification Examination in Sleep Medicine.

In November 2007, the first Certification Examination in Sleep Medicine was administered to 1,882 candidates under the cosponsorship of five member boards of the American Board of Medical Specialties (ABMS)--the American Board of Internal Medicine, the American Board of Family Medicine, the American Board of Otolaryngology, the American Board of Pediatrics, and the American Board of Psychiatry and Neurology. The pass rate was 73%. This paper chronicles the history of a certification examination in Sleep Medicine and the development of this new ABMS examination.

The snoring child.

Snoring is a common manifestation of obstructive sleep apnea and represents one end of the spectrum of sleep-related breathing disorders. Children with primary snoring initially may develop OSAS later, so inquiring about symptoms of OSAS should be part of each visit. Obstructive sleep apnea can result in serious cardiovascular and metabolic consequences and neurocognitive deficits. Adenotonsillar hypertrophy remains the most common cause of OSA although the rising prevalence of obesity is of increasing importance. Polysomnography remains the gold standard in the diagnoses of OSAS and in assessing the risks associated with surgery. Most children with OSAS can be treated with adenotonsillectomy in the ambulatory surgery center. However, there are children at risk for severe OSAS and for postoperative complications, who will need PICU care. In addition to adenotonsillectomy, OSAS can be treated successfully in referral centers with other surgical approaches and by the use of positive airway pressure. Children with obesity-related OSAS often require CPAP or BPAP for control of OSAS.

Precursors of cardiorespiratory events in infants detected by home memory monitor.

In 1,079 infants monitored for >700,000 hr at home for apnea or bradycardia, we found an association between infants having multiple events exceeding conventional or a priori defined more extreme thresholds and less favorable developmental outcome at 1 year of age than infants with few or no events. If it is necessary to prevent such events to minimize risk for developmental morbidity, there is reason to determine whether there are disturbances in advance of the apnea or bradycardia that herald their onset. In the 85 infants with at least 1 extreme event and 1 conventional event, we hypothesized that apnea and bradycardia do not occur de novo but rather are preceded by cardiorespiratory and hemoglobin O2 saturation changes. We compared recorded time intervals preceding these events, and we analyzed three preceding time intervals for each conventional and extreme event, and each non-event recording: Time-2 hr: up to 2 hr before; Time-1 hr: up to 1 hr before; and Time-75 sec: the 75 sec immediately preceding each event. O2 saturation progressively decreased preceding both conventional and extreme events, and progressive increases occurred in heart and breathing rate variability. Duration of respiratory pauses and of periodic breathing progressively increased preceding conventional events, respiratory rate variability increased immediately preceding conventional events and at 1 hr preceding extreme events, and O2 saturation decreased immediately preceding both conventional and extreme events. Thus, conventional and extreme events do not occur de novo but rather are preceded by autonomic instability of the cardiorespiratory system.

Adherence to and effectiveness of positive airway pressure therapy in children with obstructive sleep apnea.

OBJECTIVES: Positive airway pressure therapy (PAP) is frequently used to treat children who have obstructive sleep apnea syndrome and do not respond to adenotonsillectomy. However, no studies have evaluated objectively adherence to PAP in children, and few studies have evaluated objectively the effectiveness of PAP. The objective of this study was to determine adherence and effectiveness of PAP (both continuous [CPAP] and bilevel [BPAP] pressure) in children with obstructive apnea. METHODS: A prospective, multicenter study was performed of children who were randomly assigned in a double-blind manner to 6 months of CPAP versus BPAP. Adherence was measured objectively using the equipment's computerized output. Effectiveness was evaluated using polysomnography. RESULTS: Twenty-nine children were studied. Approximately one third of children dropped out before 6 months. Of the 21 children for whom 6-month adherence data could be downloaded, the mean nightly use was 5.3 +/- 2.5 (SD) hours. Parental assessment of PAP use considerably overestimated actual use. PAP was highly effective, with a reduction in the apnea hypopnea index from 27 +/- 32 to 3 +/- 5/hour, and an improvement in arterial oxygen saturation nadir from 77 +/- 17% to 89 +/- 6%. Results were similar for children who received CPAP versus BPAP. Children also had a subjective improvement in daytime sleepiness. CONCLUSIONS: Both CPAP and BPAP are highly efficacious in pediatric obstructive apnea. However, treatment with PAP is associated with a high dropout rate, and even in the adherent children, nightly use is suboptimal considering the long sleep hours in children.