Pneumothorax as a sequalae of vaping is a relatively recent complication being described in the literature. Smoking has classically been associated with increased risk of pneumothorax, and emerging evidence is showing that electronic cigarettes (e-cigarettes) likely carry some of the same risks. Since electronic cigarettes increased in popularity, especially among the adolescent population, there has been reported increased incidence of lung injury, including pneumothorax. We present a case of a 15-year-old female with a history of e-cigarette use admitted for recurrent pneumothorax with failure to re-expand requiring surgical intervention.

Asthma 17q21 Polymorphism Associates with COVID-19 in Children

Introduction: Lower socioeconomic status is associated with significantly poorer outcomes in weight, lung function, and pulmonary exacerbation rates in People with CF (PwCF). Global aim: We aim to reduce health disparities and inequities faced by PwCF by screening for and addressing unmet social needs. Specific aims: We aimed to increase routine Social Determinants of Health (SDoH) screening of eligible PwCF from 0% to 95% and follow-up within two weeks for those PwCF who screened positive and requested assistance from 0% to 95% by December 31, 2021. Methods: The Model for Improvement methodology was employed. A process map and a simplified failure mode effects analysis chart were created for the screening and SDoH follow-up process. Those who screened positive for SDoH and requested assistance, a follow-up contact was made to offer intervention. Intervention: Adult PwCF who had at least one UVA Clinic encounter in 2021 were screened for SDoH. The SDoH screening tool included eight domains: housing, food, transportation, utilities, health-care access, medication access, income/employment and education. Follow-up was completed with all PwCF who screened positive for SDoH. Results: A total of 132 of 142, (93.0%) PwCF eligible for screening completed the SDoH screening. Of the PwCF who completed screening, 56 (42.4%) screened positive for SDoH. A follow-up rate of 100% was achieved in June 2021 and maintained through December 2021. Conclusion: Implementing screening for SDOH and follow-up to mitigate social difficulties in adult PwCF at UVA was successful and could be reproduced at other CF care center.

An eight-year-old girl with cystic fibrosis (CF) developed a left upper lobe collapse failing to resolve with initial conventional antibiotic treatment, mucolytics and intensified physiotherapy. Mycobacterium abscessus was isolated from her sputum. Bronchoscopy revealed thick viscous mucus plugging of the left upper lobe bronchus with complete obliteration. Three bronchoscopies with saline lavage and Dornase alfa, a rhDNase, at the end of each procedure resulted in removal of this mucus plug and the re-inflation of the affected lobe, with clinical and radiological resolution. The use of flexible bronchoscopy as a ‘secondary’ treatment with 0.9% saline lavage and instillation of rhDNase is described sparsely in the literature. This is the first reported successful therapeutic resolution of a lung collapse in a CF patient with Mycobacterium abscessus, with sequential therapeutic bronchoscopies with instillation of Dornase alfa. This should be considered for lobar collapse in CF not responding to the standard therapeutic regime.

Rationale The lung clearance index (LCI) is increasingly being used in the clinical surveillance of patients with cystic fibrosis (CF). However, there are limited data on long-term variability and clinically relevant changes in LCI during routine clinical surveillance. Objectives To evaluate long-term variability of LCI and propose a threshold for a clinically relevant change. Methods Children with CF aged 4-18 years performed LCI measurements every three months as part of routine clinical surveillance during 2011-2020 in two centers. The variability of LCI during periods of clinical stability was assessed using mixed-effects models and was used to identify thresholds for clinically relevant changes. Results Repeated LCI measurements of acceptable quality (N= 858) were available in 100 patients with CF. Variability of repeated LCI measurements over time expressed as coefficient of variation (CV%) was 7.4%. The upper limit of normal (ULN) for relative changes in LCI between visits was 19%. Conclusion We report the variability of LCI in children and adolescents with CF during routine clinical surveillance. According to our data, a change in LCI beyond 19% may be considered clinically relevant. These findings will help guide clinical decisions according to LCI changes.

We read with great interest recent research by Anderson et al.1 on how NICU respiratory support affects infant feeding, and by Behnke et al.2 on the potential interference of infant feeding with successful respiratory stabilization of the preterm infant. Since both preclinical and human studies have established that nutrition plays a key role in preterm lung growth and development, a crucial aspect of any research undertaken in the field of neonatal respiratory outcomes should be the breastfeeding history. It is now becoming well established that human milk feeding actively contributes in limiting lung injury among vulnerable neonates.

People with cystic fibrosis (CF) have an amazing outlook with the treatment availability of highly effective modulators. Unfortunately, not all PwCF are eligible for modulators leading to continued pulmonary exacerbations and advanced lung disease. Additionally, optimizing diagnosis and evaluation for CF in the newborn period continues to be an area of focus for research. This review article will work to cover articles published in 2021 with high clinical relevance related to the above topics, however due to the extensive body of research published, this review will not be comprehensive.

A Pneumothorax in the Setting of COVID-19 Associated Pneumatoceles in a Pediatric PatientEsther Blondeau-Lecomte, BA1, Nancy Joseph, MBBS11Department of Pediatrics, University of Florida, Gainesville, FL, USA

Introduction: Infants and children diagnosed with BPD have a higher likelihood of recurrent hospitalizations and asthma-like symptoms. Socio-environmental factors that influence frequency and severity of pulmonary symptoms in these children during the pre-school age are poorly under-stood. In this study, we used the Area Deprivation Index (ADI) to evaluate the relationship between the socio-environmental exposures in children with BPD and respiratory outcomes during the first few years of life. Methods: A registry of subjects recruited from outpatient BPD clinics at Johns Hopkins University (n=909) and the Children’s Hospital of Philadelphia (n=125) between January 2008 and October 2021 was used. Subjects were separated into tertiles by ADI scores aggregated to ZIP codes. Care-giver questionnaires were used to assess the frequency of respiratory morbidities and acute care usage for respiratory symptoms. Results: The mean gestational age of subjects was 26.8±2.6 weeks with a mean birthweight of 909±404 grams. The highest tertile (most deprived) of ADI was significantly associated with emer-gency department visits (aOR 1.72; p=0.009), hospital readmissions (aOR 1.66; p=0.030), and activi-ty limitations (aOR 1.55; p=0.048) compared to the lowest tertile. No association was seen with steroid, antibiotic or rescue medication use, trouble breathing, or nighttime symptoms. Conclusion: In this study, children with BPD who lived in neighborhoods of higher deprivation were more likely to be re-hospitalized and have ED visits for respiratory reasons. Identifying socio-environmental factors that contribute to adverse pulmonary outcomes in children with BPD may provide opportunities for earlier interventions to improve long-term pulmonary outcomes.

The diagnosis of primary ciliary dyskinesia (PCD) is made through a combination of clinical features supported by a panel of diagnostic tests. Our cases highlight the similarities in the clinical presentation of patients with the specific immunodeficiency activated phosphatidylinositol 3-kinase delta syndrome 1 (APDS1 or PIK3CD) and PCD. We highlight the importance of repeating nasal nitric oxide testing (nNO) when PCD has not been confirmed by genetic or ciliary electron micrograph (EM) analysis in the setting of an expanded suppurative lung disease differential that includes considerations for immunodeficiency as well as PCD.

Pediatric Pulmonology , LetterElevated serum TARC/CCL17 levels are associated with childhood interstitial lung disease in patients with SFTPC gene mutationYuto Otsubo MD1; Yuji Fujita MD1; Yusuke Ando MD, PhD1; George Imataka MD, PhD1; Shigemi Yoshihara MD, PhD11Department of Pediatrics, Dokkyo Medical University, 880, Kitakobayashi, Mibu, Shimotsuga, Tochigi, 321-0207, JapanCorresponding author:Yuto OtsuboDepartment of Pediatrics, Dokkyo Medical University, 880, Kitakobayashi, Mibu, Shimotsuga, Tochigi, 321-0293, JapanTel: +81-0282-86-1111Fax: +81-0282-86-7152E-mail: [email protected]:Childhood interstitial lung disease; TARC/CCL17; SFTPCRunning head:Childhood ILD and increased TARC/CCL17 levelTo the Editor,Childhood interstitial lung disease (ILD) is a serious and often life-threatening disease that causes interstitial lung lesion formation during childhood. Several causative genes of childhood ILD, such asSFTPC , SFTPB , and ABCA3 , have been identified in some children. The pathogenesis of ILD caused by SFTPC mutations may include the accumulation of surfactant protein C (SP-C) in vesicles, inhibition of pulmonary surfactant reuptake, and decreased secretion of SP-C, but this remains to be confirmed.1Thymus and activation-regulated chemokine/C-C motif chemokine ligand 17 (TARC/CCL17) is a known disease marker of atopic dermatitis. Recently, an association between idiopathic pulmonary fibrosis, a representative disease with pulmonary interstitial lesions, and TARC/CCL17 has been reported,2 but none between childhood ILD and TARC/CCL17.Here we report our experience of a case of childhood ILD in which the patient had an SFTPC mutation and an elevated TARC/CCL17 level at disease onset that decreased as the patient improved with treatment. TARC/CCL17 may be involved in the pathogenesis of ILD in children withSFTPC mutation, which is different from the pathogenesis of atopic dermatitis.An otherwise healthy 15-month-old girl was admitted to our hospital with fever, difficulty breathing, and poor oral intake. Nine days prior to the visit, nasal discharge and cough appeared and gradually worsened; subsequently, poor oral intake appeared. No fine crackles were noted. The patient required supplemental oxygen and was admitted to the hospital. She had no history of respiratory impairment at birth, but she had a family history of ILD in her maternal grandmother. Informed consent was obtained from the patient’s guardians for the publication of this case report.Laboratory tests showed a white blood cell count of 941 × 109/L, neutrophil count of 58%, C-reactive protein level of 0.01 mg/dL, lactate dehydrogenase level of 929 IU/L, Krebs von den Lungen-6 (KL-6) level of 909 U/mL (normal range < 500 U/mL), surfactant protein A level of 2770 ng/mL (normal <43.8 ng/mL), and surfactant protein D level of 319 ng/mL (normal <43 ng/mL), which were suspicious findings for ILD (Table 1). ß-D-glucan level was 7.9 pg/mL (normal <20 pg/mL) and cytomegalovirus antibodies were negative for both IgG and IgM. Chest radiography showed bilateral frosted shadows (Fig. 1), and a chest computed tomography scan showed bilateral diffuse frosted shadows (Fig. 2), leading to ILD diagnosis.Although prednisolone was started on the 2nd day of admission, the patient’s respiratory status did not sufficiently improve, and oxygen supplementation was required. Therefore, methylprednisolone (30 mg/kg/day) was administered twice for 3 consecutive days on days 13-15 and 19-21; however, the respiratory status remained poor. Hydroxychloroquine (10 mg/kg/day) was then started on day 21, and azithromycin (10 mg/kg/day) three times a week was started on day 56, following which the respiratory status gradually improved. On drinking cold water, the patient often coughed and sometimes vomited. When the water was warmed from 4°C to approximately 20°C, coughing and cough-induced vomiting drastically decreased. On day 66 of hospitalization, the patient was discharged with home-based oxygen. Respiratory status, oxygenation, and laboratory data for ILD markers such as KL-6 gradually improved (Table 1).Genetic analysis of SFTPB , SFTPC , ABCA3 ,CSF2RA , and CSF2RB showed SFTPC mutation and p.I73T (c.218T>C), and the ILD was determined to be caused by theSFTPC mutation.Additional examination revealed elevated TARC/CCL17 level at 10,270 pg/mL (normal <998 pg/mL), but IgE (24.2 IU/mL; normal <173 IU/mL) and IL-4 (2.7 pg/mL; normal <6 pg/mL) levels were not elevated in the early stages of treatment. TARC/CCL17 level decreased to 2,122 pg/mL on day 131 after the admission. Granulocyte-macrophage colony-stimulating factor (GM-CSF) level was measured twice on days 11 and 83, and on both, the GM-CSF level was under 5 pg/mL without significant elevation. Anti-GM-CSF antibody (0.3 U/mL; normal <1.7 U/mL) was negative.It has been hypothesized that many of these effector cell populations are recruited by TARC/CCL17 and act profibrogenically, but the details remain largely unknown.3) SFTPC mutations increase the number of abnormal alveolar type 2 epithelial cells (AT2) due to impaired metabolism of SP-C. A knock-in mouse model capable of regulating the expression of an isoleucine-to-threonine substitution at codon 73 (p.I73T) in SFTPC, at the same site as in the present case, showed persistently elevated TARC/CCL17 level in the bronchoalveolar lavage fluid (BALF). Furthermore, the same study also reported that TARC/CCL17 is specifically released by AT2.3 In ILD caused by SFTPC mutations, its pathogenesis involves AT2 hyperplasia. The decrease in TARC/CCL17 level in our patient suggests that either AT2 itself or TARC/CCL17 production from AT2 itself decreased with treatment. In this case, we report, for the first time, elevated serum TARC/CCL17 level in a patient with SFTPC mutation, which decreased with treatment.Our patient showed no symptoms of atopic dermatitis, and she had no skin condition, and no elevation of IgE and IL-4 levels. In the SFTPC p.I73T mouse model mentioned above, no significant level of IL-4 or IL-13 was detected in BALF, and no involvement of the Th2 response was observed.This high TARC/CCL17 level was not considered to be a result of the GM-CSF cascade. TARC/CCL17 is released from macrophages as a product of the GM-CSF cascade.4) GM-CSF is also known to be produced by AT2.5) However, in this case, serum GM-CSF levels were normal and not elevated, both at the beginning of treatment and after improvement.The limitation of this case is that bronchoalveolar lavage was not performed; therefore, the evaluation was based on serum level rather than local lung findings.This case suggests that TARC/CCL17 is involved in ILD pathogenesis. Further elucidation of the chemokine and receptor signaling cascade may lead to the targeting of some stages for therapy, which may be an important issue for future medical treatment. Therefore, elucidation of this pathogenesis is desirable.References1) Beers MF, Mulugeta S. Surfactant protein C biosynthesis and its emerging role in conformational lung disease. Annu Rev Physiol 2005;67:663-696.2) Sivakumar P, Ammar R, Thompson JR, Luo Y, Streltsov D, Porteous M, McCoubrey C, Ill EC, Beers MF, Jarai G, et al. Integrated plasma proteomics and lung transcriptomics reveal novel biomarkers in idiopathic pulmonary fibrosis. Respir Res 2021;22;273:1-13.3) Nureki SI, Tomer Y, Venosa A, Katzen J, Russo SJ, Jamil S, Barrett M, Nguyen V, Kopp M, Mulugeta S, et al. Expression of mutant Sftpc in murine alveolar epithelia drives spontaneous lung fibrosis. J Clin Invest 2018;128:4008-4024.4) Hamilton JA. GM-CSF-dependent inflammatory pathways. Front Immunol 2019;10;2055:1-8.5) Woo YD, Jeong D, Chung DH. Development and functions of alveolar macrophages. Mol Cells 2021;44:292-300.Conflicts of interest:The authors disclose no conflicts.Contributors:YO cared for the patient, conceived the concept of the case report, and drafted the initial manuscript. YF, YA, GI, and SY critically reviewed the manuscript for intellectual content. All authors approved the final manuscript as submitted and agreed to be accountable for all aspects of the work. All authors have read and approved the final manuscript.Acknowledgment:We would like to thank Editage (www.editage.com) for English language editing.We thank Dr. Goro Koinuma, Division of Pulmonology, National Center for Child Health and Development, Tokyo, Japan, for his invaluable expert opinion regarding the diagnosis and treatment of the patients.Sources of funding:No funding was obtained for this study.

Background: Children should be weaned from the ventilator once their clinical condition improves. Extubation failure is associated with poorer clinical outcomes in children. Predictive indicators of successful extubation are needed. This study aims to evaluate the predictive value of ultrasonographic diaphragm imaging could help predict weaning success. Methods: In this prospective, observational study conducted between March and December 2021, children between 1 month and 10 years of age who were mechanically ventilated for more than 48 hours were included. Diaphragm ultrasound (DUS) examinations were performed at the end of 2-hour extubation readiness test (ERT). The end-inspiratory thickness, end-expiratory thickness, diaphragmatic thickening fraction, diaphragmatic excursion, inspiratory slope and expiratory slope were evaluated. Results: Twenty-four (60%) patients were successfully extubated, while 16 (40%) required invasive or non-invasive mechanical ventilation support which were classified as failed extubation group. Three of the sixteen patients in the failed extubation group required re-intubation. Diaphragm thickening fraction was significantly greater in the successful weaning group (55,05 ± 23,75% vs. 30,9 ± 10,38%) (p<0,001). Diaphragm excursion was significantly greater in the SW group (14 ± 4,4 mm vs 11,05 ± 3,25 mm) (p<0,001). DTF and DE were found to have a sensitivity and specificity of 91.67 %, 87.50 %, and 83.33 %, 81.25 %, respectively. Conclusion: Diaphragm ultrasound is a feasible and promising tool to guide physicians during weaning from IMV. Among all DUS measurements, the DE and DTF indexes showed better performance in extubation failure than other diaphragmatic parameters.

Background Children with tracheostomies are at an increased risk of bacterial respiratory tract infections. Infections caused by multidrug-resistant organisms (MDROs) are more difficult to treat and can result in severe complications. We investigated the risk factors and sequelae of MDRO positivity in tracheostomy and chronic ventilator-dependent children. Methods We performed a retrospective chart review of 75 tracheostomy and chronic ventilator-dependent children at St. Louis Children’s Hospital. Data on demographics, respiratory cultures, hospitalizations, emergency department (ED) visits, and antibiotic usage were collected. We determined the frequency of MDRO positivity and compared the number of hospitalizations, number of ED visits, and antibiotic usage in patients with and without MDRO-positive cultures. Patient clinical variables were analyzed before and after MDRO acquisition. Results We found 75.7% (56/74) of our participants had an MDRO-positive culture, with methicillin-resistant Staphylococcus aureus (MRSA, n=36, 64%) and Pseudomonas aeruginosa (n=8, 14%) being the most commonly detected organisms. Patients with MDRO-positive cultures had a greater number of annual non-pulmonary admissions [OR=1.99, 95% CI (1.21-3.29), P= 0.008], inpatient antibiotic courses [OR=1.27, 95% CI (1.07-1.50), P=0.006], total antibiotic courses [OR=1.26, 95% CI (1.08-1.48), P= 0.004], and chronic antibiotic use [OR=2.31, 95% CI (1.12-4.74), P=0.03] compared to MDRO-negative participants. Patients that acquired MDROs during the study period subsequently required increased outpatient antibiotics [P= 0.006] but did not have increased pulmonary admissions or ED visits. Conclusion Frequent antibiotic usage and hospitalizations increase the risk of MDRO acquisition in children with tracheostomies and ventilator-dependence. Further antibiotic stewardship may help prevent resistant infections in technology-dependent children.

Introduction: There is evidence for increased risk of eating disorders in individuals with diet-treated chronic illnesses, however, data in patients with Cystic Fibrosis (CF) is less clear. No studies have evaluated avoidant/restrictive food intake disorder (ARFID) in the CF population. We investigated the prevalence of disordered eating, including ARFID, in adolescents and young adults with CF. Methods: Patients with CF aged 14-35 years were recruited to complete three validated surveys: (1)Eating Disorder Examination Questionnaire (EDE-Q), (2)Nine-Item Avoidant/Restrictive Food Intake Disorder Scale (NIAS), and (3)Cystic Fibrosis Questionnaire-Revised (CFQ-R). Univariate linear regression analysis identified baseline risk factors associated with these survey scores. Variables with univariate p<0.20 were considered for inclusion in a multivariable linear regression model. Backwards stepwise linear regression was used to identify the final model. Results: A total of 52 patients enrolled. The prevalence of eating disorder measured on the EDE-Q was 9.6%, and on the NIAS was 13.5%. The CFQ-R eating and weight subscales were associated with scores on the EDE-Q, and CFQ-R eating subscale and being dF508 homozygous were correlated with the NIAS total score. Discussion: A clinically significant number of participants screened positive for disordered eating on the EDE-Q and NIAS. Scores on the eating and weight scales of the CFQ-R were associated with the scores on these surveys. Further work is needed to better understand the optimal way to use such tools to screen and treat for eating disorders in individuals with CF.

Background: Cystic fibrosis is a common cause of pancreatic exocrine insufficiency. Clinically pancreatic insufficiency is treated as a permanent problem. However, new cystic fibrosis transmembrane conductance regulator (CFTR) protein modulator therapies, like ivacaftor, can change pancreatic function in children. Also, children with residual CFTR function mutations may be pancreatic insufficient in infancy and spontaneously become pancreatic sufficient. Aims: To evaluate the benefit of reviewing pancreatic function, testing and diagnosis, of a cohort and repeat testing to patients with the potential to change function. Methods: all children with cystic fibrosis managed at Perth Children’s Hospital at the end of 2019 were reviewed for pancreatic function testing at diagnosis, genotype and current modulator and pancreatic enzyme replacement therapy use. Children with the potential to change pancreatic function were offered repeat testing. Results: 204 children were included. 11 children were prescribed ivacaftor and four of these became pancreatic sufficient. Five children with a residual CFTR function mutation were pancreatic insufficient at diagnosis. Four became pancreatic sufficient. Conclusion: there is benefit in re-evaluating pancreatic function in children with cystic fibrosis regularly, especially if on ivacaftor or pancreatic insufficient with a residual CFTR function mutation.

Background: Pediatric bronchoscopy is an important tool in pediatric pulmonology. However, the practices involved in the procedure are variable. Objective: To evaluate prevalent practice and variations in pediatric flexible bronchoscopy in India. Methods: An online survey conducted between September 2018 to March 2019 via Google forms. The survey was sent to members of the Respiratory Chapter of IAP, personal contacts, and members of Indian Chest Society. Physicians performing flexible bronchoscopy in children were asked to respond. Survey had 95 questions in seven domains including patient preparation, sedation, procedural aspects, monitoring, bronchoscope cleaning, and complications. Results: The survey received 24 (14 in private sector) complete responses from 14 cities. Pediatric bronchoscopy was mainly done for diagnostic purposes. Conscious sedation was used by most (19, 79%). Midazolam plus fentanyl 9 (37.5%) was the preferred sedation regimen. Routine atropine was used by 4 (16%). For topical anaesthesia- nebulized only, both nebulized and spray as go, and spray as go lignocaine only was used by 1 (4.2%), 6 (25%), and 17 (71%) centres, respectively. The methods of providing oxygen during bronchoscopy were free flow (9,37.5%), nasal prongs (8,33.3%), mask (6,25%), and LMA (1,4.2%). Therapeutic procedures included removal of mucus plugs (17, 71%), bronchoscopic intubation (11, 45%) and foreign body removal (10, 41%). The suction for BAL included wall mounted suction in maximum (15, 62.5%). The number of aliquots for BAL varied from 2-6 and volume for each aliquot also varied (1-2 ml/kg or 5-10 ml). The complications rate of less than 5 % was reported by almost all. Conclusion: There is large variation in pediatric flexible bronchoscopy practices across the country highlighting the need to develop a uniform guideline.

Background: In this pilot study, we investigated whether induced sputum (IS) could serve as a viable alternative to bronchoalveolar lavage (BAL) and yield robust inflammatory biomarkers in toddlers with cystic fibrosis (CF) featuring minimal structural lung disease. Methods: We collected IS, BAL (right middle lobe and lingula) and blood, and performed chest computed tomography (CT) scans from 2-year-olds with CF (N=11), all within a single visit. Inflammatory biomarkers included 20 soluble immune mediators and neutrophil elastase (NE), as well as frequency and phenotype of T cells, monocytes / macrophages and neutrophils. Results: At the molecular level, nine mediators showed similar levels in IS and BAL (CXCL1, CXCL8, IL-1, IL-1RA, IL-6, CCL2, CXCL10, M-CSF, VEGF-A), four were higher in IS than in BAL (CXCL5, IL-1, CXCL11, TNFSF10) and two were present in IS but undetectable in BAL (IL-10, IFN-). Meanwhile, soluble NE had lower activity in IS than in BAL. At the cellular level, T-cell frequency was lower in IS than in BAL. Monocytes / macrophages were dominant in IS and BAL with similar frequencies but differing expression of CD16 (lower in IS), CD115 and surface-associated NE (higher in IS). Neutrophil frequency and phenotype did not differ between IS and BAL. Conclusions: IS collected from 2-year-olds with CF yields biomarkers of early airway inflammation with good agreement with BAL notably with regards to molecular and cellular outcomes related to neutrophils and monocytes/macrophages.

Successful Extubation in Preterm InfantsTo the Editor,I read with great interest the article by O’Connor et al1 describing factors that lower the likelihood of successful extubation by day 14 in mechanically ventilated neonates with or at risk of developing bronchopulmonary dysplasia (BPD), born at <30week gestational age (GA). These factors were younger GA at birth, and at the time of commencing steroids had higher MAPs and had higher oxygen requirements. They studied 287 neonates and noted that each additional week of GA at birth led to a 1.53 increase in the odds of successful extubation. Higher average fraction of inspired oxygen (FiO2) requirements in the preceding 24 h resulted in a 0.94 decrease in the odds of successful extubation and higher mean airway pressure (MAP) resulted in 0.76 decrease in odds of successful extubation.I have been using the probability of successful extubation calculator (http://extubation.net/), which incorporates the same factors as described by Connor et al 1. The calculator was described earlier by Gupta et al 2. They incorporated GA, MAP and FiO2 in the calculation, same as Connor et al 1. The only difference was the inclusion of the respiratory severity score (RSS), which is nothing but a product of MAP and FiO2 [(RSS= mean airway pressure (cm H2O) x FiO2 (0.21-1.00)].Although, we have a probability score model for successful extubation among preterm infants, as described by Gupta et al 2, I do agree with Connor et al 1 that we need to develop prognostic scoring model for intubated preterm infants.References:O’Connor K, Hurst C, Llewellyn S, Davies M. Factors associated with successful extubation following the first course of systemic dexamethasone in ventilator-dependent preterm infants with or at risk of developing bronchopulmonary dysplasia [published online ahead of print, 2022 Jan 7]. Pediatr Pulmonol . 2022;10.1002/ppul.25821. doi:10.1002/ppul.25821Gupta D, Greenberg RG, Sharma A, et al. A predictive model for extubation readiness in extremely preterm infants. J Perinatol . 2019;39(12):1663-1669. doi:10.1038/s41372-019-0475-xAuthor:Shabih Manzar, MDLouisiana State University Health Sciences CenterDepartment of Pediatrics1501 Kings HighwayShreveport, LA 71103Phone: 318-626-1623Fax: 318-675-6059Email: [email protected] contribution: Dr. Manzar wrote the draft.Funding and financial support: NoneConflict of interest: None