Evaluation of lung function on impulse oscillometry in preschool children born late preterm

Pulmonary function using impulse oscillometry system and clinical outcomes at age 4 years in children born extremely preterm with or without bronchopulmonary dysplasia

This study aimed to describe the early assessment of lung function and respiratory morbidity in children born extremely preterm with or without bronchopulmonary dysplasia (BPD).

METHODS

This was a prospective study including all the children born at gestational age ≤28 weeks who received treatment in the NICU of the Centre Intercommunal de Créteil in France, from January 2006 to March 2012. Lung function, using the impulse oscillometry system, respiratory morbidity and growth were assessed at age 4 years. Lung function and clinical course of children were compared in children with and without BPD.

RESULTS

We included 136 extremely premature children; 26 (19 %) had BPD. Children with and without BPD did not significantly differ in resistance measurements at 5 Hz (R5) and 20 Hz (R20) and reactance (X5) measurements at age 4 years. A total of 104 (76 %) pre-term children had respiratory resistance R5 above the 95th percentile for the reference population (z-score >1.64), regardless of BPD status. The mean (SD) R5 z-score for all children was 2.1 (±0.7), whereas the mean (SD) R20 was in the normal range (z-score = 1.1 [±0.3]). After treatment with bronchodilators, all children showed no significant change in resistance. The prevalence of asthma symptoms at age 4 years was common and estimated at 30 % regardless of BPD status.

CONCLUSION

Early assessment of lung function by the impulse oscillometry system revealed that most preschool children who were born extremely preterm had abnormal total airway resistance regardless of BPD status. The system is an essential tool for the early assessment of children born prematurely.

Lung mechanics and respiratory morbidities in school-age children born moderate-to-late preterm

BACKGROUND

Late and moderate prematurity may have an impact on pulmonary function during childhood. The present study aimed to investigate lung mechanics in school-age children born moderate-to-late preterm (MLPT).

METHODS

Children aged 5-10 years were enrolled in this case-control study. Lung function and bronchodilator response were assessed by impulse oscillometry (IOS) at two hospital-based specialized clinics. A structured questionnaire was employed to assess respiratory morbidities.

RESULTS

A total of 123 children was divided into two groups: case (MLPT) n = 52 and control (children born at term) n = 71. The results showed no difference between groups in mean baseline IOS variables: R5 0.80 ± 0.20 vs 0.82 ± 0.22 kPa/L/s, p = 0.594, R20 0.54 ± 0.13 vs 0.55 ± 0.13 kPa/L/s, p = 0.732, R5-R20 0.26 ± 0.12 vs 0.27 ± 0.15 kPa/L/s, p = 0.615, X5 -0.29 ± 0.01 vs -0.29 ± 0.1 kPa/L/s, p = 0.990, Fres 21.1 ± 3.3 vs 21.7 ± 3.1 L/s, p = 0.380, and AX 2.7 ± 3.36 vs 2.5 ± 1.31 kPa/L/s, p = 0.626. Bronchodilator response and the occurrence of respiratory morbidities after birth were also similar between groups.

CONCLUSIONS

This study found lung mechanics parameters to be similar in school-age children born MLPT and those born at term, suggesting that pulmonary plasticity continues to occur in children up to school age.

IMPACT

Late and moderate prematurity is associated with an increased risk of reduced pulmonary function during childhood. Follow-up reports in adolescents and adults born MLPT are scarce but have indicated pulmonary plasticity with normalization of airway function. Our results show that the lung function in school-age children born MLPT is similar to that of children born at term.

Intra-breath oscillometry for the evaluation of lung function in children and adolescents with a history of preterm birth

Objective:

To assess respiratory system impedance (Z_rs) and spirometric parameters in children and adolescents with and without a history of preterm birth.

Methods:

We evaluated a sample of 51 subjects between 11 and 14 years of age: 35 who had a history of preterm birth (preterm group) and 16 who had been born at term (full-term group). Lung function was measured by spirometry, spectral oscillometry, and intra-breath oscillometry.

Results:

Neither spirometry nor spectral oscillometry revealed any statistically significant differences between the preterm and full-term groups. However, intra-breath oscillometry demonstrated significant differences between the two groups in terms of the change in resistance, reactance at end-inspiration, and the change in reactance (p < 0.05 for all).

Conclusions:

Our findings suggest that abnormalities in Z_rs persist in children and adolescents with a history of preterm birth and that intra-breath oscillometry is more sensitive than is spectral oscillometry. Larger studies are needed in order to validate these findings and to explore the impact that birth weight and gestational age at birth have on Z_rs later in life.

Shotgun Proteomics of Isolated Urinary Extracellular Vesicles for Investigating Respiratory Impedance in Healthy Preschoolers

Urine proteomic applications in children suggested their potential in discriminating between healthy subjects from those with respiratory diseases. The aim of the current study was to combine protein fractionation, by urinary extracellular vesicle isolation, and proteomics analysis in order to establish whether different patterns of respiratory impedance in healthy preschoolers can be characterized from a protein fingerprint. Twenty-one 3-5-yr-old healthy children, representative of 66 recruited subjects, were selected: 12 late preterm (LP) and 9 full-term (T) born. Children underwent measurement of respiratory impedance through Forced Oscillation Technique (FOT) and no significant differences between LP and T were found. Unbiased clustering, based on proteomic signatures, stratified three groups of children (A, B, C) with significantly different patterns of respiratory impedance, which was slightly worse in group A than in groups B and C. Six proteins (Tripeptidyl peptidase I (TPP1), Cubilin (CUBN), SerpinA4, SerpinF1, Thy-1 membrane glycoprotein (THY1) and Angiopoietin-related protein 2 (ANGPTL2)) were identified in order to type the membership of subjects to the three groups. The differential levels of the six proteins in groups A, B and C suggest that proteomic-based profiles of urinary fractionated exosomes could represent a link between respiratory impedance and underlying biological profiles in healthy preschool children.

Aerobic Capacity of Preterm Children with Very Low Birth Weight at School Age and its Associated Factors

INTRODUCTION

Respiratory morbidities of preterm infants can cause significant ventilatory impairment thus compromising the aerobic capacity in childhood and adolescence. Therefore, the present study was conducted to evaluate the aerobic capacity in school age preterm children with VLBW and its associated factors.

METHODS

A cross-sectional study was conducted among preterm born with VLBW and term children, both aged 6-9 years. An individualized symptom-limited treadmill testing protocol performed aerobic capacity. Measured variables: oxygen pulse (PuO₂), percentage of maximum heart rate for age (%HR max), tidal volume/inspiratory capacity ratio (TV/IC), oxygen consumption (VO₂) peak, and the ratio of the anaerobic threshold of gas exchange to the predicted percentage of maximum VO₂ (VO₂@LA/%VO₂ max.pred.) were compared between groups. Univariate and multiple linear regression analyses were used to determine the factors associated with aerobic capacity.

RESULTS

Thirty-four preterm and 32 term children were included. Similar VO₂ peak and the other variables were observed. The development of bronchopulmonary dysplasia (BPD) and being obese/overweight was positively associated with %HR max. The Z-score for height/age and birth weight <1000g was positively associated with PuO₂ and peak VO₂, and negatively associated with overweight/obesity and female sex.

CONCLUSIONS

Aerobic capacity was similar in both groups. Sex, development of BPD, birth weight <1000g and factors related to body growth, such as Z-score for height/age and overweight/obesity, were associated with aerobic capacity in preterm children with VLBW.

Early childhood health and morbidity, including respiratory function in late preterm and early term births

Late preterm (LP) and early term (ET) infants have generally been considered in the same way as their healthy full term (FT) counterparts. It is only in the last decade that an increased risk of later poor health in children born LP has been recognised; evidence for health outcomes following ET birth is still emerging. However, reports are largely consistent in highlighting an increased risk, which lessens approaching FT but is measurable and persists into adolescence and beyond. The most thoroughly explored area to date is respiratory morbidity. This article reviews the body of available evidence for effects of LP birth on pulmonary function and ongoing morbidity, and other areas where an increased risk of health problems has been identified in this population. Implications for delivery of health care are considered and areas for further research are highlighted.

Does the sex of the preterm baby affect respiratory outcomes?

Being born very preterm is associated with later deficits in lung function and an increased rate of respiratory symptoms compared with term-born children. The rates of early respiratory infections are higher in very preterm-born subjects, which may independently lead to deficits in lung function in later life. As with very preterm-born children, deficits in lung function, increased respiratory symptoms and an increased risk of respiratory infections in early life are observed in late -preterm-born children. However, the rates of respiratory symptoms are lower compared with very preterm-born children. There is some evidence to suggest that respiratory outcomes may be improving over time, although not all the evidence suggests improvements. Male sex appears to increase the risk for later adverse respiratory illness. Although not all studies report that males have worse long-term respiratory outcomes than females. It is essential that preterm-born infants are followed up into childhood and beyond, and that appropriate treatment for any lung function deficits and respiratory symptoms is prescribed if necessary. If these very preterm-born infants progress to develop chronic obstructive airway disease in later life then the impact, not only on the individuals, but also the economic impact on healthcare services, is immense.

Educational aims

To report the effect of the sex of the preterm baby on respiratory outcomes.To explore the short- and long-term respiratory outcomes of preterm birth.

Evaluation of pulmonary functions in preschool children born late-preterm

AIM

The aim of this study was to evaluate the pulmonary functions of preschool children born late-preterm.

MATERIAL AND METHODS

Children aged between 3-7 years who were born at 340/7-366/7 weeks' gestation represented the target sample. Patients with a diagnosis of congenital cardiac, pulmonary and/or muscle diseases were excluded. Respiratory symptoms were evaluated using the modified asthma predictive index and International Study of Asthma and Allergies in Childhood criteria for children aged under and over 6 years, respectively. Skin prick tests were performed. Age-matched healthy controls were chosen according to the criteria proposed by the American Thoracic Society. Lung functions were evaluated using impulse oscillometry study in both groups. Data were recorded in the SPSS program.

RESULTS

A total of 139 late-preterms and 75 healthy controls participated in the study. The mean gestational week of the late-preterms was 35.3±0.9 weeks. The main admission diagnosis to neonatal intensive care unit was respiratory distress. In the postdischarge period, 54.1% were hospitalized for pulmonary infections at least once, and 57.8% were passive smoking currently. Aeroallergen sensitivity was detected as 25.8% in the late-preterm group; 34.5% and 15.1% were diagnosed as having asthma and non-asthmatic atopy, respectively. Impulse oscillometry study parameters of R5, R10, and Z5 were higher and X10 and X15 were lower in late-preterms than in controls (p<0.05). Late-preterms with and without respiratory distress in the postnatal period revealed no statistical differences for any parameters.

CONCLUSIONS

Our findings suggest that presence of increased peripheral airway resistance in late-preterms as compared to term-born controls.