Congenital Lung Malformations: Pulmonary Function Assessment Before and After Surgery.

BACKGROUND: The management of asymptomatic congenital lung malformations (CLM) is debated, and pulmonary function of patients with CLM is seldom discussed. Short-term respiratory outcome in patients operated for CLM was assessed in order to better define surgical impact. METHODS: A retrospective study on patients operated for CLM between 2012 and 2021 was performed. Respiratory function was assessed with tidal breath analysis (TBA) in spontaneous sleep within 2 years of life. Patients with comorbidities affecting pulmonary function were excluded. Three variables were studied: tPTEF/tE (time to peak tidal expiratory flow/total expiratory time), tV (tidal volume), RR (respiratory rate). Results were assessed as z-score (normal ±1.64) and expressed as median (range). Pre- and post-operative results were compared, as well as post-operative results of disease and surgery type subgroups. RESULTS: Thirty-nine patients were included. Median pre- and post-operative tPTEF/tE were normal (pre: -0.32 (-2.12; +1.56); post: -0.18 (-1.62; +2.43)). Patients with extralobar sequestration had pre-operative high median RR, which improved after sequestrectomy (pre: +1.99 (-2.49; +7.43); post -0.22 (-3.01; +1.18)). All groups had reduced pre-operative median tV, which restored after surgery (pre: -2.15 (-9.75; +0.91); post: -0.35 (-6.65; +3.14)). Patients undergoing lobectomy and patients with intralobar sequestration showed greater improvement. Median post-operative TBA results were normal for all sub-groups except for reduced tV in patients operated with thoracotomy (-2.27 (-6.12; +5.26)). CONCLUSIONS: Patients with clinically asymptomatic CLM can have pathologic pulmonary function tests, which improve after surgery. These results add to the elements in favor of an interventional approach. LEVEL OF EVIDENCE: III, Treatment study.

Dose-dependent impact of human milk feeding on tidal breathing flow-volume loop parameters across the first 2 years of life in extremely low-birth-weight infants: a cohort study.

The purpose of this study is to test the hypothesis that higher consumption of human milk (HM) in preterm infants with birth weight (BW) <1000 g is associated with improved lung function in a dose-dependent manner over the first 2 years of corrected age (CA). This retrospective study at an academic medical center included infants with BW <1000g. They had lung function assessment by the tidal breathing flow-volume loop (TBFVL) follow-up visits at 0-3-, 3-6-, 6-12-, 12-18-, and 18-24-month CA. One hundred eighty infants were included in the study with a mean (SD) gestational age 26.5 (1.90) weeks and BW 772.4 (147.0) g, 50% were female, and 60% developed BPD. 62.8% of infants received HM during the NICU stay. According to a general linear model (including GA, being small for GA (SGA), sex, human milk percentage, sepsis, and BPD), on average, each week of GA resulted in a higher tPTEF/tE of 1.24 (p = 0.039) and being SGA in a lower tPTEF/tE of 5.75 (p = 0.013) at 0-3-month CA. A higher percentage of human milk out of the total enteral intake was associated with better tPTEF/tE z-scores at 0-3 months (p = 0.004) and 18-24 months of CA (p = 0.041). BPD diagnosis was associated with a relevantly worse tPTEF/tE z-score at 6-12 months of CA (p = 0.003). CONCLUSION: Preterm infants with higher consumption of HM had significantly less airway obstruction across the first 2 years, suggesting that human milk may contribute in a dose-dependent manner to improve lung function in early childhood in former preterm infants born ELBW. WHAT IS KNOWN: • Human milk feeding reduces the risk of prematurity-related morbidities, including necrotizing enterocolitis, sepsis, lower respiratory tract infections, and BPD. Both exclusive and partial human milk feeding appear to be associated with a lower risk of BPD in preterm infants. WHAT IS NEW: • This cohort study of 180 preterm infants with birth weight < 1000 g found that exposure to human milk during hospitalization improves airway obstruction markers tPTEF/tE z-score over the first 2 years of corrected age in a dose-dependent manner.

Effect of human milk and other neonatal variables on lung function at three months corrected age.

OBJECTIVE: To evaluate the impact of human milk and different neonatal variables on tidal breathing flow-volume loop (TBFVL) parameters within three months' corrected age (CA) in infants born ≤32 wks or weighing <1500 g. METHODS: We retrospectively studied 121 infants with gestational age (GA) ≤ 32 weeks or birth weight (BW) <1500 gr who had lung function assessment within three months' CA by TBFVL analysis between June 2009 and April 2018. We investigated the impact of GA, gender, being Small for GA (SGA), sepsis, days of mechanical ventilation (MV) and human milk feeding (HMF) on later respiratory function, both in the entire group and according to BW ( ≤1000 g and >1000 g). RESULTS: The mean(SD) z-score for tidal volume (Vt) and time to peak expiratory flow to expiratory time (tPTEF/tE) were respectively -4.3 (2.5) and -0.8 (2.0) for the overall population with no significant differences between infants <1000 g or ≥1000 g. The mean(SD) Vt standardized for body weight was 6.2(2.0) ml/kg. Being female was associated with better Vt/Kg, whereas longer MV or being born SGA were associated with worst tPTEF/tE. For infants with BW < 1000 gr, tPTEF/tE was positively associated with HMF. CONCLUSION: An early TBFVL assessment within three months' CA already reveals lung function alteration in preterm infants. Being female is associated with better Vt/Kg, while longer duration of MV or being born SGA negatively affect tPTEF/tE. The positive association between HMF and better tPTEF/tE in infants with BW <1000 g has emerged, which deserves further investigation.

Tidal Breathing Measurements in Former Preterm Infants: A Retrospective Longitudinal Study.

OBJECTIVES: To investigate, in infants born preterm with or without bronchopulmonary dysplasia (BPD), the trajectory of tidal breathing flow-volume (TBFV) parameters in the first 2 years of life; the association between TBFV parameters and perinatal risk factors; and the predictive value of TBFV parameters for rehospitalizations due to respiratory infections and wheeze. STUDY DESIGN: We retrospectively analyzed TBFV measurements performed at 0-6, 6-12, and 12-24 months of corrected age in 97 infants <32 weeks of gestation and <1500 g. We assessed the association between TBFV parameters and perinatal risk-factors using linear regressions and the predictive capacity for subsequent respiratory morbidity using logistic regressions. We used the area under the curve and likelihood ratio test (LRT) to compare nested models. RESULTS: Time to peak tidal expiratory flow/expiratory time ratio (tPTEF/tE) was lower than normal for the first 2 years of corrected age. Longer duration of oxygen supplementation, intubation, and respiratory support were associated with reduced tPTEF/tE at all time points. For each z-score increase in tPTEF/tE, the OR for rehospitalizations decreased by 0.70. tPTEF/tE added significantly to BPD classifications alone in predicting rehospitalizations (area under the receiver operating characteristic curve = 0.81 vs 0.76, P value for LRT = .0012), and wheeze (area under the receiver operating characteristic curve = 0.76 vs 0.71, P value for LRT <.001). CONCLUSIONS: Infants born preterm, with and without BPD, display persistent airway obstruction during the first 2 years of life. tPTEF/tE may identify infants at greater risk of severe respiratory morbidity.

The NeoAPACHE Study Protocol I: Assessment of the Radiographic Pulmonary Area and Long-Term Respiratory Function in Newborns With Congenital Diaphragmatic Hernia.

In newborns with congenital diaphragmatic hernia (CDH), the radiographic lung area is correlated with functional residual capacity (FRC) and represents an alternative method to estimate lung hypoplasia. In a cohort of newborn CDH survivors, we retrospectively evaluated the relationship between radiographic lung area measured on the 1st day of life and long-term respiratory function. As a secondary analysis, we compared radiographic lung areas and respiratory function between patients undergoing fetal endoscopic tracheal occlusion (FETO) and patients managed expectantly (non-FETO). Total, ipsilateral, and contralateral radiographic areas were obtained by tracing lung perimeter as delineated by the diaphragm and rib cage, excluding mediastinal structures and herniated organs. Tidal volume (VT), respiratory rate (RR), and their Z-Scores when compared to the norm were collected from pulmonary function tests (PFTs) performed at 12 ± 6 months of age. Linear regression analyses using the absolute Z-Score values for each parameter were performed. In CDH survivors, an increase in total and ipsilateral lung area measured at birth was related to a reduction in the absolute Z-Score for VT in PFTs (p = 0.046 and p = 0.023, respectively), indicating a trend toward an improvement in pulmonary volumes and VT normalization. Radiographic lung areas were not significantly different between FETO and non-FETO patients, suggesting a volumetric lung increase due to prenatal intervention. However, the mean Z-Score value for RR was significantly higher in the FETO group (p < 0.001), probably due to impaired diaphragmatic motility in the most severe cases. Further analyses are necessary to better characterize the role of the radiographic pulmonary area in the prognostic evaluation of respiratory function in patients with CDH. Clinical Trial Registration: This trial was registered at ClinicalTrials.gov with the identifier NCT04396028.

Tracheal Diameter and Respiratory Outcome in Infants with Congenital Diaphragmatic Hernia Treated by Fetal Endoscopic Tracheal Occlusion.

AIM: To evaluate tracheal diameters and their clinical impact in patients with congenital diaphragmatic hernia (CDH) after fetal endoscopic tracheal occlusion (FETO). METHODS: Patients born with CDH between January 2012 and August 2016 were divided into two groups: noFETO and FETO. Tracheal diameters at three levels (T1, carina, and maximum tracheal dilation) on chest X-ray at 1, 3, 6, 12, 24, and 36 months of follow-up, requirements of invasive and noninvasive respiratory support, the incidence of respiratory infections, and results of pulmonary function tests (PFT) were compared. RESULTS: A total of 71 patients with CDH were born in the study period, and there were 34/41 survivors in the no-FETO group (82.9%) and 13/30 in the FETO group (43.3%). The maximum tracheal diameter was significantly greater in the FETO group at all ages. No differences were observed in the diameters at T1 and the carina, in the requirements of invasive and noninvasive respiratory support, and in the incidence respiratory infections. At the PFT (6-12 months), the FETO group presented higher respiratory rates (46.1 ± 6.2 vs. 36.5 ± 10.6, p = 0.02). No differences in PFT results were found between the groups after the 1st year of life. CONCLUSIONS: The FETO procedure leads to persistent tracheomegaly. However, the tracheomegaly does not seem to have a significant clinical impact.