Summary. Rationale: With increasing use of infant pulmonary function tests (IPFTs) in both clinical and research studies, appropriate interpretation of results is essential. Objectives: To investigate the potential bias associated with ''normalising'' IPF by expressing results as a ratio of body size and to develop reference ranges for tidal breathing parameters, passive respiratory mechanics (compliance [C rs ] and resistance [R rs ]) and plethysmographic functional residual capacity (FRC p ) for white infants during the first 2 years of life. Methods: IPFTs were measured using the Jaeger BabyBody system and standardized protocols. Reference equations, adjusted for body size, age, and sex where appropriate, were created using multilevel modeling. Results: The ratio of lung function to body length changes markedly with growth, thereby precluding its use for any outcome. While the ratio of tidal volume and C rs to body weight remained relatively constant with growth, this was not the case for FRC p . Even in healthy infants, a strong inverse relationship was observed between lung function/body weight and weight z-score which could distort interpretation of results in growth-restricted infants with lung disease, such as cystic fibrosis. Reference equations were derived from 153 healthy white infants on 232 test occasions (median age 35.5 weeks [range: 2.6-104.7]). Crown-heel length was the strongest predictor of IPF. Conclusions: When reporting IPF, use of size-corrected ratios should be discouraged, with interpretation instead based on appropriate reference equations. The current equations are applicable to white infants and young children up to 2 years of age, studied using the same commercially available equipment. The extent to which these equations are applicable to infants and young children of other ethnic backgrounds or who are tested with different equipment needs to be established.

Background: Information regarding recruitment of infants to research studies following the diagnosis of cystic fibrosis (CF) via newborn screening (NBS) is not currently available. This study aimed to assess parental attitudes and the feasibility of recruiting and retaining both NBS infants with CF and healthy control infants to a longitudinal, observational study. Methods: All infants underwent pulmonary function tests (PFTs) at~3 and~12 months of age. Infants with CF had additional combined chest high resolution computed tomography (HRCT), bronchoscopy and broncho-alveolar lavage (BAL) at~12 months of age. Parental attitude questionnaires (PAQs) were administered to all parents following the~3 month PFTs and to parents of infants with CF after completion of all tests at~12 months. Results: 86% (92/107) of families whose infant had CF consented to participate, of whom 92% had PFTs at~3 months of age with 99% of these having PFTs at~12 months of age. Recruitment of healthy controls was feasible but more challenging; 29% of those contacted agreed to participate; 73% of these had PFTs at~3 months of age; of whom 83% had repeated PFTs at~12 months of age. Completed PAQs were received from 71% of parents, (both of CF and healthy infants) at~3 months and from 58% parents of infants with CF at~12 months. Responses from the PAQs were generally positive, 95% of parents indicated they would recommend participation in such studies to other families. Discrepancies between responses at 3 and 12 months suggested that parental understanding of what the research entailed developed during the course of the study. Conclusions: The high recruitment and retention rates for newly diagnosed CF NBS infants to this observational study are encouraging. These findings will help inform future study design both in the field of CF and other conditions diagnosed by NBS.

BackgroundImpaired cough results in airway secretion retention, atelectasis and pneumonia in individuals with Duchenne muscular dystrophy (DMD). Lung volume recruitment (LVR) stacks breaths to inflate the lungs to greater volumes than spontaneous effort. LVR is recommended in DMD clinical care guidelines but is not well studied. We aimed to determine whether twice-daily LVR, compared with standard of care alone, attenuates the decline in FVC at 2 years in boys with DMD.MethodsIn this multicentre, assessor-blinded, randomised controlled trial, boys with DMD, aged 6–16 years with FVC >30% predicted, were randomised to receive conventional treatment or conventional treatment plus manual LVR twice daily for 2 years. The primary outcome was FVC % predicted at 2 years, adjusted for baseline FVC % predicted, age and ambulatory status. Secondary outcomes included change in chest wall distensibility (maximal insufflation capacity minus FVC) and peak cough flow.ResultsSixty-six boys (36 in LVR group, 30 in control) were evaluated (median age (IQR): 11.5 years (9.5–13.5), median baseline FVC (IQR): 85% predicted (73–96)). Adjusted mean difference in FVC between groups at 2 years was 1.9% predicted (95% CI −6.9% to 10.7%; p=0.68) in the direction of treatment benefit. We found no differences in secondary outcomes.ConclusionThere was no difference in decline in FVC % predicted with use of twice-daily LVR for boys with DMD and relatively normal lung function. The burden associated with routine LVR may outweigh the benefit. Benefits of LVR to maintain lung health in boys with worse baseline lung function still need to be clarified.Trial registration numberNCT01999075.

Objectives: To describe the current clinical practice patterns of Canadian pediatric respirologists at pediatric tertiary care institutions regarding chronic tracheostomy tube care and management of home invasive ventilation. Methods: A pediatric respirologist/pediatrician with expertise in tracheostomy tube care and home ventilation was identified at each Canadian pediatric tertiary care center to complete a 59-item survey of multiple choice and short answer questions. Domains assessed included tracheostomy tube care, caregiver competency and home monitoring, speaking valves, medical management of tracheostomy complications, decannulation, and long-term follow-up. Results: The response rate was 100% (17/17) with all Canadian tertiary care pediatric centers represented and heterogeneity of practice was observed in all domains assessed. For example, though most centers employ Bivona™ (17/17) and Shiley™ (15/17) tracheostomy tubes, variability was observed around tube change, re-use, and cleaning practices. Most centers require two trained caregivers (14/17) and recommend 24/7 eyes on care and oxygen saturation monitoring. Discharge with an emergency tracheostomy kit was universal (17/17). Considerable heterogeneity was observed in the timing and use of speaking valves and speech-language assessment. Inhaled anti-pseudomonal antibiotics are employed by most centers (16/17) though the indication, agent, and protocol varied by center. Though decannulation practices varied considerably, the requirement of upper airway patency was universally required to proceed with decannulation (17/17) independent of ongoing ventilatory support requirements. Conclusion: Considerable variability in pediatric tracheostomy tube care practice exists across Canada. These results will serve as a starting point to standardize and evaluate tracheostomy tube care nationally.

As functional respiratory impairment following COVID‐19 infection (COVID‐19) is increasingly reported in adult, data regarding children especially with pre‐existing chronic respiratory disease (PCRD) remain scarce. We retrospectively assessed clinical presentation, duration of symptoms related to COVID‐19 from paediatric patients with PCRD and compared their pre/post COVID‐19‐I spirometry values. Data from 12 patients were analysed. Timing between COVID‐19 diagnosis and subsequent functional evaluation ranged from 26 to 209 days (mean 77). The PCRD in these patients included asthma, cystic fibrosis, bronchiolitis obliterans and bronchomalacia. During COVID‐19, all clinical presentations were mild. One patient displayed persistent post‐COVID‐19 symptoms for 8 weeks after infection. Two patients presented significant deterioration of post‐COVID‐19 spirometric values with a return to pre‐COVID‐19 values in subsequent measures. We concluded that children with PCRD are not at increased risk for severe COVID disease and that most of them have no or only transient pulmonary functional impairment 1 to 7 months after COVID‐19.