In-office Maximal Voluntary Ventilation Testing Demonstrates Pulmonary Improvement Following Posterior Spinal Fusion for Adolescent Idiopathic Scoliosis.

OBJECTIVE: Pulmonary function can be impaired in patients with adolescent idiopathic scoliosis (AIS). Maximal voluntary ventilation (MVV) has been shown to be more strongly correlated with major coronal curve, and a more easily obtained measurement of pulmonary function, than forced vital capacity (FVC). We evaluated changes in pulmonary function using these 2 measures in patients with AIS in relation to changes in major coronal curves over time. METHODS: Forty-seven patients with AIS with thoracic curves ≥10 degrees performed pulmonary function tests using the Carefusion MicroLoop Spirometer at enrollment and 1 year later. Major coronal curve worsening >5 degrees was considered curve progression. RESULTS: At enrollment, 47 patients had a mean major coronal curve of 38 degrees (range: 10 to 76 degrees). One year later, 17 patients had undergone posterior spinal fusion, 9 had curve progression >5 degrees, and 21 had no progression. MVV and major coronal curve were negatively correlated (r = -0.36, P = 0.01) at enrollment. After fusion, the major coronal curve improved by a mean of 41 degrees, and MVV improved by 23% (P < 0.01), but FVC did not improve significantly (6%, P = 0.29). In stable curves, MVV improved 12% (P = 0.01) and FVC improved 9% (P = 0.007). In patients without surgery whose curves progressed an average of 11 degrees, there was no significant change in MVV or FVC (P > 0.44). CONCLUSION: This is the first study using office-based spirometry in an orthopaedic clinic showing improved pulmonary function with posterior spinal fusion and growth in patients with AIS. It is notable that MVV improved after spinal fusion, but FVC did not, as MVV appears to be a more sensitive measurement for the assessment of pulmonary function in these patients. LEVEL OF EVIDENCE: Level II.

Elevated periodic limb movement index is associated with hypoxemia in children with early onset scoliosis.

PURPOSE: Patients with early onset scoliosis are at high risk of sleep disordered breathing, sleep disruption, and adverse consequences of poor sleep. In this study, we aim to assess the prevalence of periodic limb movements of sleep in a cohort of children with early onset scoliosis and identify factors that correlate with the presence of periodic limb movements. METHODS: This is a retrospective chart review of 40 patients with EOS (ages 1-17 years) who underwent a PSG from 2003 through 2019. Data collected included age, sex, and polysomnography parameters. Descriptive statistics were used: independent T test and Pearson correlation. RESULTS: The average age was 9.6 years (SD 5.2); 22 were female. Eleven patients (27.5%) had elevated periodic limb movement index (PLMI) (≥ 5). Those with PLMI ≥ 5 had arousal index of 15.4 (SD 7.2) and those with normal PLMI having an arousal index of 9.4 (SD 4.9); this reached statistical significance (p < 0.05). Those with elevated PLMI spent 4.9 (SD 8.3) minutes with saturations below 88%, while those with normal PLMI spent 1.0 (SD 1.8); this was statistically significant. There was a moderate positive correlation between arousal index, hypoxemia, and PLMI. CONCLUSION: The study suggests that children with early onset scoliosis have higher frequency of periodic limb movements during sleep, and these may be correlated with increased arousal and with hypoxemia.

Paediatric syndromic scoliosis: proceedings of the half-day course at the 57th annual meeting of the Scoliosis Research Society.

There are some syndromes that present with unique manifestations pertaining to the spinal column. A good working understanding of these common syndromes is useful for the spinal deformity surgeons and related healthcare providers. This review attempts to encompass these unique features and discuss them in three broad groups: hypermobility syndromes, muscle pathology-related syndromes, and syndromes related to poor bone quality. This review explores the features of these syndromes underpinning the aspects of surgical and medical management. This review represents the proceedings of the Paediatric Half-Day Course at the 57th Annual Meeting of the Scoliosis Research Society.

Obstructive Apnea and Hypopnea Length in Normal Children and Adolescents.

(1) Background: Breathing is an essential function that requires both metabolic (or au-tomatic) and voluntary (behavioral) control during wakefulness but during sleep depends on metabolic control via peripheral and central chemoreceptors. Breathing during sleep disordered breathing also depends on the maturity of the neural centers and the strength of the respiratory muscles. We do not know if the response to apnea varies with age. (2) Methods: We measured the obstructive apneas and hypopneas during REM and NREM in polysomnography studies from children referred for snoring. Exclusion criteria: younger than 1 year of age, neuromuscular or syndrome comorbidity, oxygen or positive airway pressure, central apnea, and studies with loss of airflow sensors. (3) Results: Two-hundred-and-sixty-eight sleep studies were included. Mean age was 8.7 years (4.68 SD), range 1-18 years, 160 were male, and 108 were female. The 5th centile of apnea duration during NREM is above 8 s at all ages, with a tendency to increase in the oldest groups up to 10 s. During REM sleep, it shows a gradual increase from 6 s in the youngest children to 10 s in the oldest. (4) Conclusions: Apnea/hypopnea length increases with age in children and adolescents independently from sex or severity of OSA. Using adult criteria in teens seems to be accurate.

A Comparison of Maximal Voluntary Ventilation and Forced Vital Capacity in Adolescent Idiopathic Scoliosis Patients.

STUDY DESIGN: Prospective, single center. OBJECTIVE: To compare maximal voluntary ventilation (MVV) and forced vital capacity (FVC) testing in the outpatient scoliosis clinic to determine their relative feasibility and sensitivity in assessing pulmonary function in the AIS population. SUMMARY OF BACKGROUND DATA: Evidence of compromised pulmonary function in patients with severe AIS is well established. The American Thoracic Society (ATS) has established criteria for the reliability and accuracy of pulmonary function tests (PFTs), including MVV and FVC. METHODS: A total of 91 AIS patients with thoracic curves of 20° or greater were enrolled in the orthopedic clinic. Patients performed PFTs using the CareFusion MicroLoop Spirometer. MVV and FVC values were collected. Results were considered reliable or "passing" when ATS spirometer guidelines were met. RESULTS: Eighty-seven of the 91 patients (96%) met ATS criteria for the MVV test and 43 of the 91 patients (47%) met criteria for the FVC test. Both MVV (r = -0.41, p < .01) and FVC (r = -0.37, p = .01) were significantly correlated with thoracic Cobb angle. The percentile predicted (%predicted) MVV (r = -0.24, p = .03) and %predicted FVC (r = -0.32, p = .04) were also significantly correlated with thoracic Cobb angle. Of those who passed both tests (42/91 patients), 26% had abnormal MVV results with normal FVC results, and 5% had abnormal FVC results with normal MVV results. CONCLUSION: MVV and FVC correlated closely with Cobb angle. Twice as many AIS patients could perform an MVV test compared with an FVC test. MVV seems to be a more practical and sensitive PFT than FVC for assessing the pulmonary function of AIS patients in the orthopedic clinic setting. LEVEL OF EVIDENCE: Level II.

Complications in using the vertical expandable prosthetic titanium rib (VEPTR) in children.

PURPOSE: This report describes complications using the vertical expandable prosthetic titanium rib (VEPTR) for thoracic insufficiency syndrome (TIS) at a single center. METHODS: This is a prospective cohort evaluating 65 patients with rib-rib and rib-spine VEPTR devices for TIS placed between 10/2001 and 11/2014, for children with spinal or chest wall deformity. Patients were classified using the early onset scoliosis classification system (C-EOS). RESULTS: 65 patients are available for follow up. 23 congenital scoliosis, 12 neuromuscular, 14 syndromic, 2 idiopathic and 14 not classifiable by the C-EOS system including 11 chest wall reconstructions. Average age at implantation was 6.9years (range 1.3-24.8) with average follow up 6.9years (range 0.4-14.8). 22 patients had 37 complications. Those classifiable by C-EOS had complications in the normo- and hyperkyphotic groups. Implant erosion and infection were most common. The majority of complications required one additional unplanned surgery for resolution. Two complications required abandonment of a growth-friendly strategy. CONCLUSIONS: Use of VEPTR for TIS is associated with significant and frequent complications. C-EOS suggests that complications are more likely in those with normal or hyperkyphotic curves. Most complications are managed with one unplanned surgery. VEPTR is usually salvaged and abandonment of a growth-friendly strategy is unusual.

Obstructive lung disease in children with idiopathic scoliosis.

OBJECTIVE: To measure the prevalence of obstructive lung disease (OLD) among patients undergoing preoperative pulmonary assessment for idiopathic scoliosis. STUDY DESIGN: This was a retrospective, descriptive review from clinical data in a tertiary care pediatric hospital in the US. Patients (n = 176) with idiopathic scoliosis with Cobb angles of ≥ 40 degrees who performed acceptable and repeatable preoperative pulmonary function testing were included. The primary outcome measure was the forced expiratory volume in the first second (FEV1)/forced vital capacity (FVC) ratio. RESULTS: The prevalence of OLD (low FEV1/FVC ratio) was 39% (68/176 patients). In multivariate modeling, radiographic measures were poor predictors of pulmonary function outcomes of FVC (r(2) 0.06), FEV1 (r(2) 0.05), FEV1/FVC ratio (r(2) 0.08), and total lung capacity (r(2) 0.06). CONCLUSIONS: OLD is common in patients with idiopathic scoliosis. We recommend preoperative pulmonary function testing for patients with idiopathic scoliosis under consideration for spinal fusion surgery.

Obstructive lung disease is common in children with syndromic and congenital scoliosis: a preliminary study.

BACKGROUND: It is well known that restrictive lung disease (RLD) is associated with scoliosis. This study identifies that obstructive lung disease (OLD) is associated with syndromic scoliosis and congenital scoliosis. METHODS: We searched a local database for patients with scoliosis who underwent a pulmonary function testing (PFT) from 2004 to 2009. All patients with congenital scoliosis or syndromic thoracolumbar scoliosis with a Cobb angle of ≥40 degrees and acceptable and repeatable PFT testing were included in the study. OLD was defined as an forced expiratory volume in the first second/forced vital capacity ratio below 95% confidence interval. Bronchoscopy videos and computed tomography scans or magnetic resonance images were reviewed to identify anatomic causes of lower airway disease. RESULTS: A total of 18 patients met the criteria for inclusion. The median age at diagnosis was 11.3 years. The median primary Cobb angle was 60 degrees. The prevalence of OLD was 33% and RLD was 57%. The 6 children with OLD underwent preoperative bronchoscopy and chest computed tomography or magnetic resonance imaging to identify anatomic causes of lower airway obstruction. The 4 children with OLD and right-sided major thoracic curves had compression of the right mainstem bronchus between the spine (posterior) and the right pulmonary artery (anterior). The 2 children with OLD and left-sided major thoracic curves had compression of the left mainstem bronchus between the spine (posterior) and the descending aorta (anterior) or the left atrium (anterior). CONCLUSIONS: In our study, the prevalence of OLD in children with congenital scoliosis or syndromic scoliosis was 33%, which was elevated when compared with the population prevalence of 2% to 5%. Mainstem airway compression from spine rotation was discovered to be the potential mechanism of disease. LEVEL OF EVIDENCE: Level IV, prognostic study investigating the effect of a patient characteristic on the outcome of disease.

Longitudinal nasopharyngeal carriage and antibiotic resistance of respiratory bacteria in indigenous Australian and Alaska native children with bronchiectasis.

BACKGROUND: Indigenous children in Australia and Alaska have very high rates of chronic suppurative lung disease (CSLD)/bronchiectasis. Antibiotics, including frequent or long-term azithromycin in Australia and short-term beta-lactam therapy in both countries, are often prescribed to treat these patients. In the Bronchiectasis Observational Study we examined over several years the nasopharyngeal carriage and antibiotic resistance of respiratory bacteria in these two PCV7-vaccinated populations. METHODS: Indigenous children aged 0.5-8.9 years with CSLD/bronchiectasis from remote Australia (n = 79) and Alaska (n = 41) were enrolled in a prospective cohort study during 2004-8. At scheduled study visits until 2010 antibiotic use in the preceding 2-weeks was recorded and nasopharyngeal swabs collected for culture and antimicrobial susceptibility testing. Analysis of respiratory bacterial carriage and antibiotic resistance was by baseline and final swabs, and total swabs by year. RESULTS: Streptococcus pneumoniae carriage changed little over time. In contrast, carriage of Haemophilus influenzae declined and Staphylococcus aureus increased (from 0% in 2005-6 to 23% in 2010 in Alaskan children); these changes were associated with increasing age. Moraxella catarrhalis carriage declined significantly in Australian, but not Alaskan, children (from 64% in 2004-6 to 11% in 2010). While beta-lactam antibiotic use was similar in the two cohorts, Australian children received more azithromycin. Macrolide resistance was significantly higher in Australian compared to Alaskan children, while H. influenzae beta-lactam resistance was higher in Alaskan children. Azithromycin use coincided significantly with reduced carriage of S. pneumoniae, H. influenzae and M. catarrhalis, but increased carriage of S. aureus and macrolide-resistant strains of S. pneumoniae and S. aureus (proportion of carriers and all swabs), in a 'cumulative dose-response' relationship. CONCLUSIONS: Over time, similar (possibly age-related) changes in nasopharyngeal bacterial carriage were observed in Australian and Alaskan children with CSLD/bronchiectasis. However, there were also significant frequency-dependent differences in carriage and antibiotic resistance that coincided with azithromycin use.

Correlating Haller Index and cardiopulmonary disease in pectus excavatum.

BACKGROUND: The Haller Index (HI) has become standard for determining the severity of pectus excavatum. We compared patterns of cardiopulmonary dysfunction and their relationship with HI in patients with pectus excavatum. METHODS: We performed cardiopulmonary exercise testing and chest computed tomography scans on 90 patients with pectus excavatum deformities at a regional pediatric hospital. RESULTS: The median HI was 4.9 in patients with combined dysfunction, 4.4 in patients with isolated pulmonary dysfunction, 3.6 in patients with isolated cardiac dysfunction, and 3.4 in patients with normal function. HI varied significantly by disease group (P < .009). HI was significantly lower in patients with normal forced vital capacity than with abnormal forced vital capacity (P = .001). However, HI was similar in patients with normal and abnormal oxygen pulse (P = .24) or peak oxygen consumption (P = .37). CONCLUSIONS: Fifty-nine percent of patients had cardiac and/or pulmonary limitation. A HI greater than 3.6 is associated with pulmonary dysfunction, but not cardiac dysfunction.

Strategic plan for pediatric respiratory diseases research: an NHLBI working group report.

The Division of Lung Diseases of the National Heart, Lung, and Blood Institute (NHLBI) recently held a workshop to identify gaps in our understanding and treatment of childhood lung diseases and to define strategies to enhance translational research in this field. Leading experts with diverse experience in both laboratory and patient-oriented research reviewed selected areas of pediatric lung diseases, including perinatal programming and epigenetic influences; mechanisms of lung injury, repair, and regeneration; pulmonary vascular disease; sleep and control of breathing; and the application of novel translational methods to enhance personalized medicine. This report summarizes the proceedings of this workshop and provides recommendations for emphasis on targeted areas for future investigation. The priority areas identified for research in pediatric pulmonary diseases included: (1) epigenetic and environmental influences on lung development that program pediatric lung diseases; (2) injury, regeneration, and repair in the developing lung; (3) pulmonary vascular disease in children; (4) development and adaptation of ventilatory responses to postnatal life; (5) nonatopic wheezing: aberrant large airway development or injury?; (6) strategies to improve assessment, diagnosis, and treatment of pediatric respiratory diseases; and (7) predictive and personalized medicine for children.

Strategic plan for pediatric respiratory diseases research: an NHLBI working group report.

The Division of Lung Diseases of the National Heart, Lung and Blood Institute (NHLBI) recently held a workshop to identify gaps in our understanding and treatment of childhood lung diseases and to define strategies to enhance translational research in this field. Leading experts with diverse experience in both laboratory and patient-oriented research reviewed selected areas of pediatric lung diseases, including perinatal programming and epigenetic influences; mechanisms of lung injury, repair, and regeneration; pulmonary vascular disease (PVD); sleep and control of breathing; and the application of novel translational methods to enhance personalized medicine. This report summarizes the proceedings of this workshop and provides recommendations for emphasis on targeted areas for future investigation. The priority areas identified for research in pediatric pulmonary diseases included: (1) epigenetic and environmental influences on lung development that program pediatric lung diseases, (2) injury, regeneration, and repair in the developing lung, (3) PVD in children, (4) development and adaptation of ventilatory responses to postnatal life, (5) nonatopic wheezing: aberrant large airway development or injury? (6) strategies to improve assessment, diagnosis, and treatment of pediatric respiratory diseases, and (7) predictive and personalized medicine for children.

Interdisciplinary leadership training outcomes of Maternal and Child Health-funded pediatric pulmonary centers.

OBJECTIVES: To describe career paths, leadership accomplishments, and extent of incorporation of Maternal and Child Health Bureau (MCHB) values into professional activities of all previous long-term trainees. METHOD: In 1998 the Pediatric Pulmonary Centers (PPCs) completed a Leadership Training Outcomes Survey of all previous long-term trainees. The survey included 1) characteristics, 2) career paths, 3) current professional activities, 4) leadership roles and activities, and 5) career incorporation of MCHB values. RESULTS: There was a 63% response rate (N = 274) from 431 mailed surveys. Most respondents provided clinical care in varied health-related settings. Of the respondents, 44% (N = 120) served mothers, 87% (N = 239) served children, and 78% (N = 214) served children with special health care needs. Forty-seven percent of the mothers and children served were from racial or ethnic minority groups. Ninety-two percent (N = 252) of respondents had conducted training since graduation and 56% (N = 153) had provided technical assistance. Many provided leadership in the acquisition and dissemination of new knowledge through research publication (33%), advocacy (37%), and program administration/oversight (87%). Thirty percent of the respondents (N = 83) had received special recognition awards for professional activities. CONCLUSIONS: Most PPC graduates serve families and children as a central aspect of their career, providing or enhancing family-centered, community-based, culturally competent, comprehensive interdisciplinary care.

Sequelae of severe respiratory syncytial virus infection in infancy and early childhood among Alaska Native children.

OBJECTIVE: In 1993-1996, we conducted a nested case-control study to determine risk factors for hospitalization with respiratory syncytial virus (RSV) infection among Alaska Native infants and young children. In the current study, we returned to former RSV case-patients and their control subjects during 1999-2001 to determine whether children who are hospitalized with RSV at <2 years of age are more likely to develop chronic respiratory conditions. METHODS: For each former RSV case-patient and control subject from remote villages in southwest Alaska, we reviewed medical records, interviewed parents, performed physical examinations and spirometry, collected sera, and analyzed chest radiographs. Case-patients were identified through surveillance for RSV hospitalization, and matched control subjects without lower respiratory infection (LRI)-related hospitalization were identified. RESULTS: Hospitalization for RSV infection was associated with a significant increase in wheezing, LRIs, and asthma diagnosis during the first 4 years of life. The association decreased with age and was no longer significant by 5 years of age. However, hospitalization for RSV infection was associated with increased respiratory symptoms and increased chronic productive cough at 5 to 8 years of age. Children who were hospitalized with RSV were not more likely at follow-up to have allergies, eczema, or a positive family history of asthma. CONCLUSIONS: Severe RSV infection in infancy may produce airway injury, which is manifested in chronic productive cough with or without wheezing and recurrent LRIs. Although the association of RSV infection with wheezing seems to be transient, children remain at higher risk for chronic productive cough at 5 to 8 years of age. RSV prevention modalities may prevent sequelae that occur early and later in childhood.