The management of very mild and mild asthma in preschoolers, children, and adolescents.

This practice point summarizes recommendations from the Canadian Thoracic Society's 2021 "Guideline update: Diagnosis and management of asthma in preschoolers, children, and adults." New recommendations include: a decrease in the frequency of daytime symptoms and reliever use to ≤2 per week in the asthma control criteria; assessing for risk of asthma exacerbation; not using as-needed short-acting beta-agonists alone in patients at higher risk for exacerbation; and the option of as-needed budesonide/formoterol (bud/form) in those ≥12 years old if they are unable to take daily inhaled corticosteroids despite extensive asthma education and support. The preference for daily inhaled corticosteroids to manage mild asthma in children, and the recommendation against intermittent short courses of inhaled corticosteroids, are unchanged.

La prise en charge de l'asthme léger et très léger chez les enfants d'âge préscolaire, les enfants et les adolescents.

Le présent point de pratique résume la mise à jour des lignes directrices de la Société canadienne de thoracologie publiée en 2021 sur le diagnostic et la prise en charge de l'asthme chez les enfants d'âge préscolaire, les enfants et les adultes. Ces nouvelles recommandations incluent, parmi les critères de contrôle de l'asthme, une diminution de la fréquence des symptômes diurnes et de l'utilisation de médicaments pour soulager l'asthme à un maximum de deux fois par semaine. Elles comprennent également l'évaluation du risque d'exacerbation de l'asthme, la non-utilisation de bêta-agonistes à courte durée d'action seuls au besoin chez les patients à plus fort risque d'exacerbation et la possibilité d'administrer du budésonide-formotérol au besoin aux jeunes de 12 ans ou plus qui sont incapables de prendre des corticostéroïdes inhalés au quotidien malgré une éducation sur l'asthme et un soutien importants. La préférence pour la prise quotidienne de corticostéroïdes inhalés afin de traiter l'asthme léger chez les enfants et la recommandation d'éviter les courts traitements intermittents de corticostéroïdes inhalés ne changent pas.

Infant Body Mass Index or Weight-for-Length and Risk of Undernutrition in Childhood Among Children with Cystic Fibrosis.

OBJECTIVES: To compare performance of weight-for-length and body mass index as estimators of undernutrition in children with cystic fibrosis (CF). STUDY DESIGN: We analyzed pediatric anthropometric data from the Cystic Fibrosis Foundation Patient Registry. Undernutrition was defined by weight-for-length z score (WFLZ) or body mass index z score (BMIZ) ≤-1 (15th-percentile). Group 1, reference group, consisted of subjects with both BMIZ and WFLZ >-1; group 2: BMIZ ≤-1 and WFLZ >-1; group 3: BMIZ >-1 and WFLZ ≤-1; and group 4: BMIZ and WFLZ ≤-1. Group differences in length-for-age-Z across ages 2-24 months were tested using generalized estimating equations. The association of group at age 2 months with BMIZ <-1 at age 6 years was tested using logistic regression adjusted for demographic and disease characteristics. RESULTS: Overall, 163 482 anthropometric measurements were available from 12 640 individuals, of whom 16.8% were discordant for undernutrition status at age 2 months. Discordance (1.5%-10%) was less common with increasing age. Length-for-age-Z was lower in group 2 than group 1 and group 3 between birth and 24 months (P < .05). Odds of WFLZ-defined undernourished at 2 months were lower for shorter individuals (OR 1.5, CI 1.4-1.6, P < .001). Undernutrition risk at age 6 years was greater for group 2 vs group 3 (OR 1.9 vs 1.0, P < .001). CONCLUSIONS: Infants with cystic fibrosis classified as undernourished by BMIZ, but not WFLZ, had greater risk of undernourished status later in childhood. Infants with low BMIZ but normal WFLZ tended to be shorter, suggesting BMIZ may better capture undernourished status than WFLZ in shorter infants.

Respiratory prehabilitation in pediatric anesthesia in children with muscular and neurologic disease.

Children with neuromuscular, chronic neurologic, and chest wall diseases are at increased risk of postoperative respiratory complications including atelectasis, pneumonia, and respiratory failure with the possible need for reintubation or even tracheostomy. These complications negatively impact patient outcomes, including increased healthcare resource utilization and increased surgical mortality. In these children, the existing respiratory reserve is often inadequate to withstand the stresses brought on during anesthesia and surgery. A thorough clinical assessment and objective evaluation of pulmonary function and gas exchange can help identify which children are at particular risk for poor postoperative outcomes and thus merit preoperative interventions. These may include initiation and optimization of non-invasive ventilation and mechanical insufflation-exsufflation. Furthermore, such an evaluation will help identify children who may require a postoperative extubation plan tailored to neuromuscular diseases. Such strategies may include avoidance of pre-extubation lung decruitment by precluding continuous positive airway pressure trials, aggressively weaning to room air and directly extubating to non-invasive ventilation with a high inspiratory to expiratory pressure differential of at least 10 cm H20. Children with cerebral palsy and other neurodegenerative or neurodevelopmental disorders are a more heterogeneous group of children who may share some operative risk factors with children with neuromuscular disease; they may also be at risk of sleep-disordered breathing, may also require non-invasive ventilation or mechanical insufflation-exsufflation, and may have associated chronic lung disease from aspirations that may require perioperative treatment.

Genetic potential and height velocity during childhood and adolescence do not fully account for shorter stature in cystic fibrosis.

BACKGROUND: Despite improved health, shorter stature is common in cystic fibrosis (CF). We aimed to describe height velocity (HV) and contribution of height-related genetic variants to height (HT) in CF. METHODS: HV cohort: standard deviation scores (-Z) for HT, mid-parental height-adjusted HT (MPAH), and HV were generated using our Pediatric Center's CF Foundation registry data. HV-Z was compared with population means at each age (5-17 y), the relationship of HV-Z with HT-Z assessed, and HT-Z compared with MPAH-Z. GRS cohort: HT genetic risk-Z (HT-GRS-Z) were determined for pancreatic exocrine sufficient (PS) and insufficient (PI) youth and adults from our CF center and their relationships with HT-Z assessed. RESULTS: HV cohort: average HV-Z was normal across ages in our cohort but was 1.5× lower (p < 0.01) for each SD decrease in HT-Z. MPAH-Z was lower than HT-Z (p < 0.001). GRS cohort: HT-GRS-Z more strongly correlated with HT-Z and better explained height variance in PS (rho = 0.42; R2= 0.25) vs. PI (rho = 0.27; R2 = 0.11). CONCLUSIONS: Despite shorter stature compared with peers and mid-parental height, youth with CF generally have normal linear growth in mid- and late childhood. PI tempered the heritability of height. These results suggest that, in CF, final height is determined early in life in CF and genetic potential is attenuated by other factors. IMPACT: Children with CF remain shorter than their healthy peers despite advances in care. Our study demonstrates that children with CF have persistent shorter stature from an early age and fail to reach their genetic potential despite height velocities comparable to those of average maturing healthy peers and similar enrichment in known height increasing single-nucleotide polymorphisms (SNPs). Genetic risk scores better explained variability in pancreatic sufficient than in pancreatic insufficient individuals, suggesting that other modifying factors are in play for pancreatic insufficient individuals with CF. Given the CF Foundation's recommendation to target not only normal body mass index, but normal height percentiles as well, this study adds valuable insight to this discussion.

Nasal Nitric Oxide in Primary Immunodeficiency and Primary Ciliary Dyskinesia: Helping to Distinguish Between Clinically Similar Diseases.

PURPOSE: Primary ciliary dyskinesia (PCD) is a rare disorder of the mucociliary clearance leading to recurrent upper and lower respiratory tract infections. PCD is difficult to clinically distinguish from other entities leading to recurrent oto-sino-pulmonary infections, including primary immunodeficiency (PID). Nasal nitric oxide (nNO) is a sensitive and specific diagnostic test for PCD, but it has not been thoroughly examined in PID. Past publications have suggested an overlap in nNO levels among subjects with PCD and PID. We sought to determine if nNO measurements among patients diagnosed with PID would fall significantly above the established PCD diagnostic cutoff value of 77 nL/min. METHODS: Children > 5 years old and adults with definitive PID or PCD diagnoses were recruited from outpatient subspecialty clinics. Participants underwent nNO testing by standardized protocol using a chemiluminescence analyzer and completed a questionnaire concerning their chronic oto-sino-pulmonary symptoms, including key clinical criteria specific to diagnosed PCD (neonatal respiratory distress at term birth, year-round cough or nasal congestion starting before 6 months of age, any organ laterality defect). RESULTS: Participants included 32 patients with PID, 27 patients with PCD, and 19 healthy controls. Median nNO was 228.9.1 nL/min in the PID group, 19.7 nL/min in the PCD group, and 269.4 in the healthy controls (p < 0.0001). Subjects with PCD were significantly more likely to report key clinical criteria specific to PCD, but approximately 25% of PID subjects also reported at least 1 of these key clinical criteria (mainly year-round cough or nasal congestion). CONCLUSIONS: While key clinical criteria associated with PCD often overlap with the symptoms reported in PID, nNO measurement by chemiluminescence technology allows for effective discrimination between PID and PCD.

Whole Body Plethysmography: Practical Considerations.

Pediatric pulmonary plethysmography is an important tool used in the diagnosis of lung diseases. Understanding the physiology underlying the functioning of the test can aid the health care provider in its interpretation. The following article reviews the basic science behind whole body plethysmography, and provides an overview of the types of plethysmographs available. Finally, the limitations of the available normative values are discussed.

Bronchopulmonary dysplasia - trends over three decades.

OBJECTIVES: To describe the characteristics of bronchopulmonary dysplasia (BPD) and respiratory distress syndrome subjects, along with the trends in severity and mortality associated with BPD over the past three decades. METHODS: Retrospective study of BPD and respiratory distress syndrome subjects born between 1980 and 2008, and admitted to Montreal Children's Hospital (Montreal, Quebec). Data were abstracted from hospital records. RESULTS: Gestational age and birth weight were correlated with the occurrence of BPD with each additional week of gestation and 100 g in birth weight being associated with an OR of developing BPD of 0.77 and 0.89, respectively. BPD severity was associated with male sex, Apgar score and the occurrence of neonatal pneumonia. Significant trends were observed for lower mortality despite lower gestational age and birth weight, greater maternal age and multiple gestations. CONCLUSION: Mortality from BPD has improved over the past three decades despite significant trends toward more pronounced prematurity and lower birth weights.

OBJECTIF: Décrire les caractéristiques des sujets atteints de la dysplasie bronchopulmonaire (DBP) et du syndrome de détresse respiratoire, de même que les tendances quant à la gravité de la DBP et à la mortalité s'y rapportant depuis 30 ans. MÉTHODOLOGIE: Les chercheurs ont mené une étude rétrospective des sujets atteints de la DBP et du syndrome de détresse respiratoire nés entre 1980 et 2008 et hospitalisés à L'Hôpital de Montréal pour enfants, au Québec. Ils ont tiré les données des dossiers hospitaliers. RÉSULTATS: Les chercheurs ont corrélé l'âge gestationnel et le poids de naissance avec l'occurrence de DBP, chaque nouvelle semaine de grossesse et nouvelle tranche de 100 g de poids de naissance s'associant à un RRR de DBP de 0,77 et de 0,89, respectivement. La gravité de la DBP s'associait au sexe masculin, à l'indice d'Apgar et à l'occurrence d'une pneumonie néonatale. Les chercheurs ont observé des tendances importantes de diminution de la mortalité malgré un âge gestationnel et un poids de naissance moins élevés, l'âge plus avancé des mères et des gestations multiples. CONCLUSION: La mortalité liée à la DBP a diminué depuis 30 ans, malgré des tendances importantes vers une prématurité plus prononcée et un plus petit poids à la naissance.