Lung Ultrasound to Monitor Extremely Preterm Infants and Predict Bronchopulmonary Dysplasia. A Multicenter Longitudinal Cohort Study

Lung ultrasound in early prediction of bronchopulmonary dysplasia in pre-term babies

PURPOSE

Bronchopulmonary dysplasia (BPD) is a respiratory morbidity related to prematurity. Early prediction of BPD allows the selection of patients who would benefit from new therapies. Lung ultrasound (LUS) is a non-invasive diagnostic tool that has proven to be reliable for many neonatal diseases recently. The study aimed to detect the role of LUS in predicting BPD at days 7 and 14 of life in preterm babies.

METHODS

This was a prospective cohort study that included 95 preterm babies ≤ 34 weeks. Lung ultrasounds were performed on days 7 and 14 of life.

RESULTS

The mean gestational age of the studied neonates was 30.25 ± 2.21 weeks. The mean birth weight was 1347.66 ± 432.14 gm. Patients who developed BPD had statistically significantly higher LUS scores on both days 7 and 14 of life. At first examination, a LUS score > 8 showed a sensitivity of 83.33% and a specificity of 60.87%, whereas at follow-up, a LUS score > 8 showed a sensitivity of 76.39% and a specificity of 82.61%. The multivariate logistic regression analysis shows that the most important factors associated with BPD were gestational age ≤ 30 weeks, LUS score at first examination > 8, platelets ≤ 245 × 109/L, segment neutrophils ≤ 42%, and CRP > 5 mg/l.

CONCLUSIONS

The LUS score predicts BPD at 7 and 14 days of life. LUS scores increased with increasing BPD severity. LUS score > 8 was an independent factor in the prediction of BPD.

Improving early diagnosis of bronchopulmonary dysplasia

INTRODUCTION

Bronchopulmonary disease (BPD) is associated with long-term neurodevelopmental and cardiorespiratory complications, often requiring significant use of resources. To reduce this healthcare burden, it is essential that those at high risk of BPD are identified early so that strategies are introduced to prevent disease progression. Our aim was to discuss potential methods for improving early diagnosis in the first week after birth.

AREAS COVERED

A narrative review was undertaken. The search strategy involved searching PubMed, Embase and Cochrane databases from 1967 to 2024. The results of potential biomarkers and imaging modes are discussed. Furthermore, the value of scoring systems is explored.

EXPERT OPINION

BPD occurs as a result of disruption to pulmonary vascular and alveolar development, thus abnormal levels of factors regulating those processes are promising avenues to explore with regard to early detection of high-risk infants. Data from twin studies suggests genetic factors can be attributed to 82% of the observed difference in moderate to severe BPD, but large genome-wide studies have yielded conflicting results. Comparative studies are required to determine which biomarker or imaging mode may most accurately diagnose early BPD development. Models which include the most predictive factors should be evaluated going forward.

Blinding Assessments in Neonatal Ventilation Meta-Analyses: A Systematic Meta-Epidemiological Review

INTRODUCTION

Randomization and blinding are generally important in randomized trials. In neonatology, blinding of ventilation strategies is unfeasible if not impossible and we hypothesized that its importance has been overestimated, while the peculiarities of the neonatal patient and the specific outcomes have not been considered.

METHODS

For this meta-epidemiological review, we searched PubMed and Scopus databases in November 2023. We included all meta-analyses focusing on ventilation, published in past 5 years, and reporting either mortality or bronchopulmonary dysplasia (BPD) as an outcome. We extracted the information about how the authors had analyzed risk of bias and evidence certainty.

RESULTS

We screened 494 abstracts and included 40 meta-analyses. Overall, 13 of the 40 reviews assessed blinding properly. Australian and European authors were most likely to perform correct assessment of the blinding (p = 0.03) and the use of RoB 2.0 tool was also associated with proper assessment (p < 0.001). In multivariate regression, the use of RoB 2.0 was the only factor associated with a proper assessment (Beta 0.57 [95% confidence interval: 0.29-0.99]). GRADE ratings were performed in 25 reviews, and the authors downgraded the evidence certainty due to risk of bias in 19 of these and none of these reviews performed the blinding assessment correctly.

CONCLUSION

In past neonatal evidence syntheses, the role of blinding has been mostly overestimated, which has led to downgrading of evidence certainty. Objective outcomes (such as mortality and BPD) do not need to be downgraded due to lack of blinding, as the knowledge of the received intervention does not influence the outcome assessment.

Prognostic Relevance of the Lung Ultrasound Score: A Multioutcome Study in Infants with Respiratory Distress Syndrome

OBJECTIVE

 There is growing evidence for the usefulness of the lung ultrasound score (LUS) in neonatal intensive care. We evaluated whether the LUS is predictive of outcomes in infants with respiratory distress syndrome (RDS).

STUDY DESIGN

 Neonates less than 34 weeks of gestational age were eligible for this prospective, multicenter cohort study. The outcomes of interest were the need for mechanical ventilation (MV) at <72 hours of life, the need for surfactant (SF), successful weaning from continuous positive airway pressure (CPAP), extubation readiness, and bronchopulmonary dysplasia. Lung scans were taken at 0 to 6 hours of life (Day 1), on Days 2, 3, and 7, and before CPAP withdrawal or extubation. Sonograms were scored (range 0-16) by a blinded expert sonographer. The area under the receiver operating characteristic curve (AUC) was used to estimate the prediction accuracy of the LUS.

RESULTS

 A total of 647 scans were obtained from 155 newborns with a median gestational age of 32 weeks. On Day 1, a cutoff LUS of 6 had a sensitivity (Se) of 88% and a specificity (Sp) of 79% to predict the need for SF (AUC = 0.86), while a cutoff LUS of 7 predicted the need for MV at <72 hours of life (Se = 89%, Sp = 65%, AUC = 0.80). LUS acquired prior to weaning off CPAP was an excellent predictor of successful CPAP withdrawal, with a cutoff level of 1 (Se = 67%, Sp = 100%, AUC = 0.86).

CONCLUSION

 The LUS has significant predictive ability for important outcomes in neonatal RDS.

KEY POINTS

· Lung ultrasound has significant prognostic abilities in neonatal RDS.. · Early sonograms (0-6 h of life) accurately predict the requirement for SF and ventilation.. · Weaning off CPAP is effective when the LUS (range 0-16) is less than or equal to 1..

Correlation between early postnatal body weight changes and lung ultrasound scores as predictors of bronchopulmonary dysplasia in preterm infants: A secondary analysis of a prospective study

Recent research links early weight changes (EWC) with bronchopulmonary dysplasia (BPD) in preterm neonates, while lung ultrasound score (LUS) has shown promise in predicting BPD. We aimed to explore the correlation between LUS and EWC as markers of extravascular lung edema and to investigate the correlation between LUS and EWC in preterm infants with respiratory distress syndrome regarding future BPD development. This secondary analysis of a prospective study involved infants ≤ 28 weeks gestation. Enrolled infants underwent lung ultrasound assessment on postnatal days 3, 7 and 14, measuring LUS. EWC was computed on the same time points. Infants were classified as either having BPD or not. Descriptive statistics, correlation coefficient, and area under the receiver operating characteristic (AUROC) curve analysis were utilized. Of 132 infants, 70 (53%) had BPD. Univariate analysis revealed statistically significant differences in LUS and EWC at days 3, 7, and 14 between BPD and no-BPD groups (p < 0.001). A statistically significant but weak positive correlation existed between LUS and EWC (r0.37, r0.29, r0.24, and p < 0.01) at postnatal days 3, 7, and 14, respectively. AUROC analysis indicated LUS having superior predictive capacity for the need for invasive mechanical ventilation at day 14 as well as the later BPD development compared to EWC (p < 0.0001).

CONCLUSION

In a cohort of extreme preterm infants, our study revealed a positive yet weak correlation between LUS and EWC, suggesting that EWC was not the major contributing to the evolving chronic lung disease.

WHAT IS KNOWN

• Recent evidence links Early Weight-Changes with bronchopulmonary dysplasia in preterm neonates. • Lung ultrasound score has shown promise in early prediction of the subsequent development of bronchopulmonary dysplasia in preterm infants. No studies have examined the correlation between Early Weight-Changes and Lung ultrasound score in preterm infants during first 2 weeks after birth.

WHAT IS NEW

• Our study demonstrated a positive and statistically significant correlation between early LUS and EWC, indicating their potential role as early predictors for the subsequent development of BPD in extreme preterm infants. • The weak correlation between the two parameters may stem from the possible restricted influence of EWC, given that it may not be the primary factor contributing to the evolving chronic lung disease.

Quantitative Lung Ultrasonography to Guide Surfactant Therapy in Neonates Born Late Preterm and Later

Importance

Surfactant administration may be needed in late preterm through full-term neonates, but the pathophysiology of their respiratory failure can be different from that of early preterm neonates. The lung ultrasonography score (LUS) is accurate to guide surfactant replacement in early preterm neonates, but to our knowledge, it has not yet been studied in the late preterm through full-term neonatal population.

Objective

To assess whether LUS is equally accurate to predict surfactant need in late preterm through full-term neonates as in early preterm neonates.

Design, Setting, and Participants

This prospective, international, multicenter diagnostic study was performed between December 2022 and November 2023 in tertiary academic neonatal intensive care units in France, Italy, Spain, and the US. Late preterm through full-term neonates (≥34 weeks' gestation) with respiratory failure early after birth were enrolled.

Exposure

Point-of-care lung ultrasonography to calculate the neonatal LUS (range, 0-18, with higher scores indicating worse aeration), which was registered in dedicated research databases and unavailable for clinical decision-making.

Main Outcomes and Measures

The main outcomes were the area under the curve (AUC) in receiver operating characteristic analysis and derived accuracy variables, considering LUS as a replacement for other tests (ie, highest global accuracy) and as a triage test (ie, highest sensitivity). Sample size was calculated to assess noninferiority of LUS to predict surfactant need in the study population compared with neonates born more prematurely. Correlations of LUS with the ratio of hemoglobin oxygen saturation as measured by pulse oximetry (SpO2) to fraction of inspired oxygen (FiO2) and with the oxygen saturation index (OSI) were assessed.

Results

A total of 157 neonates (96 [61.1%] male) were enrolled and underwent lung ultrasonography at a median of 3 hours (IQR, 2-7 hours) of life; 32 (20.4%) needed surfactant administration (pretest probability, 20%). The AUC was 0.87 (95% CI, 0.81-0.92). The highest global accuracy and sensitivity were reached for LUS values higher than 8 or 4 or lower, respectively. Subgroup analysis gave similar diagnostic accuracy in neonates born late preterm (AUC, 0.89; 95% CI, 0.81-0.97; n = 111) and early term and later (AUC, 0.84; 95% CI, 0.73-0.96; n = 46). After adjusting for gestational age, LUS was significantly correlated with SpO2:FiO2 (adjusted β, -10.4; 95% CI, -14.0 to -6.7; P < .001) and OSI (adjusted β, 0.2; 95% CI, 0.1-0.3; P < .001).

Conclusions and Relevance

In this diagnostic study of late preterm through full-term neonates with respiratory failure early after birth, LUS accuracy to predict surfactant need was not inferior to that observed in earlier preterm neonates. An LUS higher than 8 was associated with highest global accuracy (replacement test), suggesting that it can be used to guide surfactant administration. An LUS value of 4 or lower was associated with the highest sensitivity (triage test), suggesting it is unlikely for this population to need surfactant.

Lung ultrasound score in the decision of patent ductus arteriosus closure in neonates

PURPOSE

We aimed to investigate the role of lung ultrasound (LUS) score in the closure of hemodynamically insignificant patent ductus arteriosus (PDA) and the clinical findings of the patients before and after closure.

METHODS

The study groups (107 preterm neonates under 34 gestational weeks) were classified as hemodynamically significant PDA (group 1), hemodynamically insignificant PDA with closure therapy (group 2), hemodynamically insignificant PDA without closure therapy (group 3), and no PDA group (group 4) based on the echocardiography. 6- and 10-region LUS scores were compared for each group.

RESULTS

There was a significant difference between groups 1 and 3 on first, third, and seventh days. In contrast, groups 1 and 2 had similar LUS scores on the first, third, and seventh days. There was a negative correlation between LUS scores on the first and third days and gestational age, birth weight, the first- and fifth-minute APGAR scores, and there was a positive correlation between aortic root to left atrium ratio, and PDA diameter/weight ratio.

CONCLUSION

We observed that LUS scores in patients with hemodynamically insignificant PDA treated with closure therapy were similar to in patients with hemodynamically significant PDA. Thus, LUS score can have role in PDA closure in preterm neonates. However, more comprehensive studies are needed.

Combining lung ultrasound and oscillatory mechanics for assessing lung disease in very preterm infants

BACKGROUND

We investigated whether combining lung ultrasound scores (LUSs) and respiratory system reactance (Xrs) measured by respiratory oscillometry explains the severity of lung disease better than individual parameters alone.

METHODS

We performed a prospective observational study in very preterm infants. Forced oscillations (10 Hz) were applied using a neonatal mechanical ventilator (Fabian HFOi, Vyaire). We used the simultaneous respiratory severity score (RSS = mean airway pressure × FIO2) as a primary outcome. We built linear mixed-effect models to assess the relationship between Xrs z-score, LUS and RSS and compared nested models using the likelihood ratio test (LRT).

RESULTS

We enrolled 61 infants (median (Q1, Q3) gestational age = 30.00 (26.86, 31.00) weeks) and performed 243 measurements at a postnatal age of 26 (13, 41) days and postmenstrual age of 33.14 (30.46, 35.86) weeks. Xrs z-score and LUS were independently associated with simultaneous RSS (p < 0.001 for both). The model including Xrs and LUS explained the RSS significantly better than Xrs (p value LRT < 0.001) or LUS alone (p value LRT < 0.001).

CONCLUSIONS

Combining LUS and Xrs z-score explains the severity of lung disease better than each parameter alone and has the potential to improve the understanding of the underlying pathophysiology.

IMPACT

Combining respiratory system reactance by oscillometry and lung ultrasound score explains the respiratory support requirement (e.g., proxy of the severity of lung disease) significantly better than each parameter alone. We assessed the relationship between lung ultrasound and respiratory system reactance in very preterm infants for the first time. Combining respiratory oscillometry and lung ultrasound has the potential to improve the understanding of respiratory pathophysiology.

Lung ultrasound-guided fluid resuscitation in neonatal septic shock: A randomized controlled trial

This randomized controlled trial aimed to determine whether lung ultrasound-guided fluid resuscitation improves the clinical outcomes of neonates with septic shock. Seventy-two patients were randomly assigned to undergo treatment with lung ultrasound-guided fluid resuscitation (LUGFR), or with usual fluid resuscitation (Control) in the first 6 h since the start of the sepsis treatment. The primary study outcome was 14-day mortality after randomization. Fourteen-day mortalities in the two groups were not significantly different (LUGFR group, 13.89%; control group, 16.67%; p = 0.76; hazard ratio 0.81 [95% CI 0.27-2.50]). The LUGFR group experienced shorter length of neonatal intensive care unit (NICU) stays (21 vs. 26 days, p = 0.04) and hospital stays (32 vs. 39 days, p = 0.01), and less fluid was used in the first 6 h (77 vs. 106 mL/kg, p = 0.02). Further, our study found that ultrasound-guided fluid resuscitation can significantly reduce the incidence of acute kidney injury (25% vs. 47.2%, p = 0.05) and intracranial hemorrhage (grades I-II) within 72 h (13.9% vs. 36.1%, p = 0.03). However, no significant difference was found in the resolution of shock within 1 h or 6 h, use of mechanical ventilation or vasopressor support, time to achieve lactate level < 2 mmol/L, and the number of participants developing hepatomegaly in the first 6 h.

CONCLUSION

Lung ultrasound is a noninvasive and convenient tool for predicting fluid overload in neonatal septic shock. Fluid resuscitation guided by lung ultrasound can shorten the length of hospital and NICU stays, reduce the amount of fluid used in the first 6 h, and reduce the risk of acute kidney injury and intracranial hemorrhage.

TRIAL REGISTRATION

Registered in Guangdong Second Provincial General Hospital: 2021-IIT-156-EK, date of registration: November 13, 2021. And ClinicalTrials.gov: NCT06144463 (retrospectively registered).

WHAT IS KNOWN

• Excessive fluid resuscitation in neonates with septic shock had worse outcomes.

WHAT IS NEW

• Lung ultrasound should be routinely used to guide fluid resuscitation in neonatal septic shock.

Lung ultrasound for the sick child: less harm and more information than a radiograph

In the realm of emergency medicine, the swift adoption of lung ultrasound (LU) has extended from the adult population to encompass pediatric and neonatal intensivists. LU stands out as a bedside, replicable, and cost-effective modality, distinct in its avoidance of ionizing radiations, a departure from conventional chest radiography. Recent years have witnessed a seamless adaptation of experiences gained in the adult setting to the neonatal and pediatric contexts, underscoring the versatility of bedside Point of care ultrasound (POCUS). This adaptability has proven reliable in diagnosing common pathologies and executing therapeutic interventions, including chest drainage, and central and peripheral vascular cannulation. The surge in POCUS utilization among neonatologists and pediatric intensivists is notable, spanning economically advanced Western nations with sophisticated, high-cost intensive care facilities and extending to low-income countries. Within the neonatal and pediatric population, POCUS has become integral for diagnosing and monitoring respiratory infections and chronic and acute lung pathologies. This, in turn, contributes to a reduction in radiation exposure during critical periods of growth, thereby mitigating oncological risks. Collaboration among various national and international societies has led to the formulation of guidelines addressing both the clinical application and regulatory aspects of operator training. Nevertheless, unified guidelines specific to the pediatric and neonatal population remain lacking, in contrast to the well-established protocols for adults. The initial application of POCUS in neonatal and pediatric settings centered on goal-directed echocardiography. Pivotal developments include expert statements in 2011, the UK consensus statement on echocardiography by neonatologists, and European training recommendations. The Australian Clinician Performed Ultrasound (CPU) program has played a crucial role, providing a robust academic curriculum tailored for training neonatologists in cerebral and cardiac assessment. Notably, the European Society for Paediatric and Neonatal Intensive Care (ESPNIC) recently disseminated evidence-based guidelines through an international panel, delineating the use and applications of POCUS in the pediatric setting. These guidelines are pertinent to any professional tending to critically ill children in routine or emergency scenarios. In light of the burgeoning literature, this paper will succinctly elucidate the methodology of performing an LU scan and underscore its primary indications in the neonatal and pediatric patient cohort. The focal points of this review comprise as follows: (1) methodology for conducting a lung ultrasound scan, (2) key ultrasonographic features characterizing a healthy lung, and (3) the functional approach: Lung Ultrasound Score in the child and the neonate.  Conclusion: the aim of this review is to discuss the following key points: 1. How to perform a lung ultrasound scan 2. Main ultrasonographic features of the healthy lung 3. The functional approach: Lung Ultrasound Score in the child and the neonate What is Known: • Lung Ultrasound (LUS) is applied in pediatric and neonatal age for the diagnosis of pneumothorax, consolidation, and pleural effusion. • Recently, LUS has been introduced into clinical practice as a bedside diagnostic method for monitoring surfactant use in NARDS and lung recruitment in PARDS. What is New: • Lung Ultrasound (LUS) has proven to be useful in confirming diagnoses of pneumothorax, consolidation, and pleural effusion. • Furthermore, it has demonstrated effectiveness in monitoring the response to surfactant therapy in neonates, in staging the severity of bronchiolitis, and in PARDS.

The value of lung ultrasound score in neonatal respiratory distress syndrome: a prospective diagnostic cohort study

Rationale

The accurate diagnosis of critically ill patients with respiratory failure can be achieved through lung ultrasound (LUS) score. Considering its characteristics, it is speculated that this technique might also be useful for patients with neonatal respiratory distress syndrome (NRDS). Thus, there is a need for precise imaging tools to monitor such patients.

Objectives

This double-blind randomized cohort study aims to investigate the impact of LUS and related scores on the severity of NRDS patients.

Methods

This study was conducted as a prospective double-blind randomized study. Bivariate correlation analysis was conducted to investigate the relationship between LUS score and Oxygenation Index (OI), Respiratory Index (RI), and Sequential Organ Failure Assessment (SOFA) score. Spearman's correlation coefficient was used to generate correlation heat maps, elucidating the associations between LUS and respective parameters in different cohorts. Receiver Operating Characteristic (ROC) curves were employed to calculate the predictive values, sensitivity, and specificity of different scores in determining the severity of NRDS.

Results

This study ultimately included 134 patients admitted to the intensive care unit (ICU) between December 2020 and June 2022. Among these patients, 72 were included in the NRDS cohort, while 62 were included in the Non-NRDS (N-NRDS) cohort. There were significant differences in the mean LUS scores between NRDS and N-NRDS patients (p < 0.01). The LUS score was significantly negatively correlated with the OI (p < 0.01), while it was significantly positively correlated with the RI and SOFA scores (p < 0.01). The correlation heatmap revealed the highest positive correlation coefficient between LUS and RI (0.82), while the highest negative correlation coefficient was observed between LUS and OI (-0.8). ROC curves for different scores demonstrated that LUS score had the highest area under the curve (0.91, 95% CI: 0.84-0.98) in predicting the severity of patients' conditions. The combination of LUS and other scores can more accurately predict the severity of NRDS patients, with the highest AUC value of 0.93, significantly higher than using a single indicator alone (p < 0.01).

Conclusion

Our double-blind randomized cohort study demonstrates that LUS, RI, OI, and SOFA scores can effectively monitor the lung ventilation and function in NRDS. Moreover, these parameters and their combination have significant predictive value in evaluating the severity and prognosis of NRDS patients. Therefore, these results provide crucial insights for future research endeavors.

Lung ultrasound score as a tool to predict severity of bronchopulmonary dysplasia in neonates born ≤25 weeks of gestational age

OBJECTIVE

The primary aim was to evaluate whether the addition of the posterior lung aided in diagnostic accuracy of predicting bronchopulmonary dysplasia (BPD) vs moderate-severe BPD (msBPD); the secondary aim was to explore the diagnostic accuracy of two protocols for BPD vs msBPD.

STUDY DESIGN

This was a single-center prospective observational study. Preterm infants with a gestational age ≤ 25 weeks were included. Two LUS score protocols were evaluated on the 14th day of life (DOL): (A) evaluating the anterolateral (LUS score-al) lung and (B) the anterolateral combined with posterior (LUS score-alp) lung. The LUS score range for the two protocols was 0-32 and 0-48, respectively.

RESULTS

A total of eighty-nine infants were enrolled. Both the LUS score-al and LUS score-alp were higher in neonates developing BPD and msBPD than in the rest of the cohort (LUS score-al 24 (23,26) vs 22 (20,23); LUS score-alp 36 (34,39) vs 28 (25,32)) (LUS score-al 25 (24,26) vs 23 (21,24); LUS score-alp 40 (39,40) vs 34 (28,36)). The LUS score-al on the 14th DOL showed a moderate diagnostic accuracy to predict BPD and msBPD (AUC 95% CI: 0.797 [0.697-0.896]; 0.811[0.713-0.909]), while the LUS score-alp significantly improved diagnostic accuracy of BPD and msBPD (AUC 95% CI: 0.902 [0.834-0.970]; 0.922 [0.848-0.996]). A cutoff of 25 points in the LUS score-al provided a sensitivity, specificity, positive likelihood ratio, and negative likelihood ratio of 76.9%, 79.4%, 3.7, and 0.3 respectively to predict msBPD. Meanwhile, that of 39 points in the LUS score-alp provided a sensitivity, specificity, positive likelihood ratio, and negative likelihood ratio of 81%, 98.4%, 50.5 and 0.19 to predict msBPD, respectively.

CONCLUSIONS

The LUS score on the 14th DOL can predict BPD and msBPD with moderate diagnostic accuracy. Apart from that, scanning posterior enhanced diagnostic accuracy.

Assessing the diagnostic accuracy of lung ultrasound in determining invasive ventilation needs in neonates on non-invasive ventilation: An observational study from a tertiary NICU in India

Effective management of neonatal respiratory distress requires timely recognition of when to transition from non-invasive to invasive ventilation. Although the lung ultrasound score (LUS) is useful in evaluating disease severity and predicting the need for surfactants, its efficacy in identifying neonates requiring invasive ventilation has only been explored in a few studies. This study aims to assess the accuracy of LUS in determining the need for invasive ventilation in neonates on non-invasive ventilation (NIV) support. From July 2021 to June 2023, we conducted a prospective study on 192 consecutively admitted neonates with respiratory distress needing NIV within 24 h of birth at our NICU in Hyderabad, India. The primary objective was the diagnostic accuracy of LUS in determining the need for invasive ventilation within 72 h of initiating NIV. We calculated LUS using the scoring system of Brat et al. (JAMA Pediatr 169:e151797, [10]). Treating physicians' assessments of the need for invasive ventilation served as the reference standard for evaluating LUS effectiveness. Out of 192 studied neonates, 31 (16.1%) required invasive ventilation. The median LUS was 5 (IQR: 2-8) for those on NIV and 10 (IQR: 7-12) for those needing invasive ventilation. The LUS had a strong discriminative ability for invasive ventilation with an AUC (area under the curve) of 0.825 (CI: 0.75-0.86, p = 0.0001). An LUS > 7 had 77.4% sensitivity (95% CI: 58.9-90.8%), 75.1% specificity (95% CI: 67.8-81.7%), 37.5% positive predictive value (PPV) (95% CI: 30.15-45.5%), 94.5% negative predictive value (NPV) (95% CI: 89.9-97.1%), 3.1 positive likelihood ratio (PLR) (95% CI: 2.2-4.3), 0.3 negative likelihood ratio (NLR) (95% CI: 0.15-0.58), and 75.5% overall accuracy (95% CI: 68.8-81.4%) for identifying invasive ventilation needs. In contrast, SAS, with a cutoff point greater than 5, has an AUC of 0.67. It demonstrates 62.5% sensitivity, 61.9% specificity, 24.7% PPV, 89.2% NPV, and an overall diagnostic accuracy of 61.9%. The DeLong test confirms the significance of this difference (AUC difference: 0.142, p = 0.04), underscoring LUS's greater reliability for NIV failure.  Conclusion: This study underscores the diagnostic accuracy of the LUS cutoff of > 7 in determining invasive ventilation needs during the initial 72 h of NIV. Importantly, while lower LUS values typically rule out the need for ventilation, higher values, though indicative, are not definitive. What is known? • The effectiveness of lung ultrasound in evaluating disease severity and the need for surfactants in neonates with respiratory distress is well established. However, traditional indicators for transitioning from non-invasive to invasive ventilation, like respiratory distress and oxygen levels, have limitations, underscoring the need for reliable, non-invasive assessment tools. What is new? • This study reveals that a LUS over 7 accurately discriminates between neonates requiring invasive ventilation and those who do not. Furthermore, the lung ultrasound score outperformed the Silverman Andersen score for NIV failure in our population.

Lung ultrasound detects regional aeration inhomogeneity in ventilated preterm lambs

BACKGROUND

Inhomogeneous lung aeration is a significant contributor to preterm lung injury. EIT detects inhomogeneous aeration in the research setting. Whether LUS detects inhomogeneous aeration is unknown. The aim was to determine whether LUS detects regional inhomogeneity identified by EIT in preterm lambs.

METHODS

LUS and EIT were simultaneously performed on mechanically ventilated preterm lambs. LUS images from non-dependent and dependent regions were acquired and reported using a validated scoring system and computer-assisted quantitative LUS greyscale analysis (Q-LUSMGV). Regional inhomogeneity was calculated by observed over predicted aeration ratio from the EIT reconstructive model. LUS scores and Q-LUSMGV were compared with EIT aeration ratios using one-way ANOVA.

RESULTS

LUS was performed in 32 lambs (~125d gestation, 128 images). LUS scores were greater in upper anterior (non-dependent) compared to lower lateral (dependent) regions of the left (3.4 vs 2.9, p = 0.1) and right (3.4 vs 2.7, p < 0.0087). The left and right upper regions also had greater LUS scores compared to right lower (3.4 vs 2.7, p < 0.0087) and left lower (3.7 vs 2.9, p = 0.1). Q-LUSMGV yielded similar results. All LUS findings corresponded with EIT regional differences.

CONCLUSION

LUS may have potential in measuring regional aeration, which should be further explored in human studies.

IMPACT

Inhomogeneous lung aeration is an important contributor to preterm lung injury, however, tools detecting inhomogeneous aeration at the bedside are limited. Currently, the only tool clinically available to detect this is electrical impedance tomography (EIT), however, its use is largely limited to research. Lung ultrasound (LUS) may play a role in monitoring lung aeration in preterm infants, however, whether it detects inhomogeneous lung aeration is unknown. Visual LUS scores and mean greyscale image analysis using computer assisted quantitative LUS (Q-LUSMGV) detects regional lung aeration differences when compared to EIT. This suggests LUS reliably detects aeration inhomogeneity warranting further investigation in human trials.

Comparison among three lung ultrasound scores used to predict the need for surfactant replacement therapy: a retrospective diagnostic accuracy study in a cohort of preterm infants

Lung ultrasound (LU) has emerged as the imaging technique of choice for the assessment of neonates with respiratory distress syndrome (RDS) at the bedside. Scoring systems were developed to quantify RDS severity and to predict the need for surfactant administration. There is no data on the comparison of the three main LU scores (LUS) proposed by Brat, Raimondi and Rodriguez-Fanjul. Moreover, there is not enough evidence to recommend which score and which cut-off has the best ability to predict surfactant need. The three LUS were compared in terms of ability to predict the need for surfactant and reproducibility in a cohort of very preterm infants. This was an observational, retrospective, multicenter study. Neonates below 32 weeks of gestational age with RDS, on non-invasive ventilation with a LU performed prior to surfactant administration (1-3 h of life) were included. Brat, Raimondi, and Rodriguez-Fanjul's scores were calculated for each patient. Receiver-operating characteristic (ROC) curve analysis was used to assess the ability to predict surfactant administration. K-Cohen test, Bland-Altman, and intraclass correlation coefficients were used to assess the intra and interobserver variability. Fifty-four preterm infants were enrolled. Brat, Raimondi, and Rodriguez-Fanjul scores showed a strong ability to predict the need for surfactant: the AUCs were 0.85 (95% CI 0.74-0.96), 0.85 (95% CI 0.75-0.96), and 0.79 (95% CI 0.67-0.92), respectively. No significant differences have been found between the AUCs using the DeLong test. Brat and Raimondi's scores had an optimal cut-off value > 8, while the Rodriguez-Fanjul's score > 10. The k-Cohen values of intraobserver agreement for Brat, Raimondi, and Rodriguez-Fanjul's scores were 0.896 (0.698-1.000), 1.000 (1.000-1.000), and 0.922 (0.767-1.000), respectively. The k-Cohen values of interobserver agreement were 0.896 (0.698-1.000), 0.911 (0.741-1.000), and 0.833 (0.612-1.000), respectively.Conclusions: The three LUS had an excellent ability to predict the need for surfactant and an optimal intra and interobserver agreement. The differences found between the three scores are minimal with negligible clinical implications. Since the optimal cut-off value differed, the same score should be used consistently within the same center. What is Known: • Lung ultrasound is a useful bedside imaging tool that should be used in the assessment of neonates with RDS • Scoring systems or lung ultrasound scores allow to quantify the severity of the pulmonary disease and to predict the need for surfactant replacement therapy What is New: • The three lung ultrasound scores by Brat, Raimondi and Rodriguez-Fanjul have an excellent ability to predict the need for surfactant replacement therapy, although with different cut-off values • All three lung ultrasound scores had an excellent intra and interobserver reproducibility.

Oscillatory mechanics trajectory in very preterm infants: a cohort study

BACKGROUND

The aim of this study was to describe the trajectory of oscillatory mechanics from the first week of life to term equivalent and evaluate whether oscillatory mechanics are associated with simultaneous lung disease in infants ≤32 weeks gestation.

METHODS

In this observational, longitudinal study, we enrolled 66 infants. Forced oscillations were applied using a neonatal mechanical ventilator (Fabian HFOi) that superimposed oscillations (10 Hz, amplitude 2.5 cmH2O) on a positive end-expiratory pressure (PEEP). Measurements were performed at 5-7-9 cmH2O of PEEP or the clinical pressure ±2 cmH2O; they were repeated at 7, 14, 28 post-natal days, and 36 and 40 weeks post-menstrual age (PMA).

RESULTS

The mean (range) gestational age of study participants was 29.2 (22.9-31.9) weeks. Nineteen infants (29%) developed bronchopulmonary dysplasia (BPD). Respiratory system reactance was significantly lower (lower compliance), and respiratory system resistance was significantly higher in infants with developing BPD from 7 post-natal days to 36 weeks PMA. All oscillatory mechanics parameters were significantly associated with the simultaneous respiratory severity score (p < 0.001 for all).

CONCLUSIONS

Serial measurements of oscillatory mechanics allow differentiating lung function trajectory in infants with and without evolving BPD. Oscillatory mechanics significantly correlate with the severity of simultaneous lung disease.

IMPACT

The results of the present study suggest that respiratory system reactance, as assessed by respiratory oscillometry, allows the longitudinal monitoring of the progression of lung disease in very premature infants. This paper describes for the first time the trajectory of oscillatory mechanics in very preterm infants with and without evolving bronchopulmonary dysplasia from the first week of life to term equivalent. Serial respiratory oscillometry measurements allow the identification of early markers of evolving bronchopulmonary dysplasia and may help personalizing the respiratory management strategy.

Lung UltrasouNd Guided surfactant therapy in preterm infants: an international multicenter randomized control trial (LUNG study)

BACKGROUND

The management of respiratory distress syndrome (RDS) in premature newborns is based on different types of non-invasive respiratory support and on surfactant replacement therapy (SRT) to avoid mechanical ventilation as it may eventually result in lung damage. European guidelines currently recommend SRT only when the fraction of inspired oxygen (FiO2) exceeds 0.30. The literature describes that early SRT decreases the risk of bronchopulmonary dysplasia (BPD) and mortality. Lung ultrasound score (LUS) in preterm infants affected by RDS has proven to be able to predict the need for SRT and different single-center studies have shown that LUS may increase the proportion of infants that received early SRT. Therefore, the aim of this study is to determine if the use of LUS as a decision tool for SRT in preterm infants affected by RDS allows for the reduction of the incidence of BPD or death in the study group.

METHODS/DESIGN

In this study, 668 spontaneously-breathing preterm infants, born at 25+0 to 29+6 weeks' gestation, in nasal continuous positive airway pressure (nCPAP) will be randomized to receive SRT only when the FiO2 cut-off exceeds 0.3 (control group) or if the LUS score is higher than 8 or the FiO2 requirements exceed 0.3 (study group) (334 infants per arm). The primary outcome will be the difference in proportion of infants with BPD or death in the study group managed compared to the control group.

DISCUSSION

Based on previous published studies, it seems that LUS may decrease the time to administer surfactant therapy. It is known that early surfactant administration decreases BPD and mortality. Therefore, there is rationale for hypothesizing a reduction in BPD or death in the group of patients in which the decision to administer exogenous surfactant is based on lung ultrasound scores.

TRIAL REGISTRATION

ClinicalTrials.gov identifier NCT05198375 . Registered on 20 January 2022.

Noninvasive Monitoring Strategies for Bronchopulmonary Dysplasia or Post-Prematurity Respiratory Disease: Current Challenges and Future Prospects

Definitions of bronchopulmonary dysplasia (BPD) or post-prematurity respiratory disease (PPRD) aim to stratify the risk of mortality and morbidity, with an emphasis on long-term respiratory outcomes. There is no univocal classification of BPD due to its complex multifactorial nature and the substantial heterogeneity of clinical presentation. Currently, there is no definitive treatment available for extremely premature very-low-birth-weight infants with BPD, and challenges in finding targeted preventive therapies persist. However, innovative stem cell-based postnatal therapies targeting BPD-free survival are emerging, which are likely to be offered in the first few days of life to high-risk premature infants. Hence, we need easy-to-use noninvasive tools for a standardized, precise, and reliable BPD assessment at a very early stage, to support clinical decision-making and to predict the response to treatment. In this non-systematic review, we present an overview of strategies for monitoring preterm infants with early and evolving BPD-PPRD, and we make some remarks on future prospects, with a focus on near-infrared spectroscopy (NIRS).

The value of hematocrit for predicting bronchopulmonary dysplasia in very low birth weight preterm infants

To determine hematocrit (HCT) and to identify independent risk factors for predicting bronchopulmonary dysplasia (BPD) in preterm infants with very low birth weight (VLBW) infants. This retrospective study included 296 premature infants with VLBW in the neonatal intensive care unit of the First Affiliated Hospital of the University of Science and Technology of China between January 2015 and December 2019. Maternal pregnant information and clinical information as well as hematological parameters of preterm babies were collected and compared. Then the maximum area under the curve of receiver operating characteristic curve was developed to estimate the predictive indicator in the blood. Finally, differential variables together with the predictive index were screened for multiple logistic regression analysis to determine independent prognostic factors for BPD. Infants were divided into a BPD group (134 cases) and a non-BPD group (162 cases). The area under the curve of HCT at postnatal 1 week was 0.737 with the sensitivity of 52.30 % and the specificity of 86.00%. Birth weight (BW) <1.12 kg, gestational age <28.4 weeks, newborn respiratory distress syndrome, mechanical ventilation ≥ 7 days, ventilation associated pneumonia, patent arterial duct, PaO2/FiO2 <300 mm Hg and HCT <0.455 at postnatal 1 week were risk factors for BPD of VLBW infants. HCT levels below 0.455 at 1 week after birth serve as a valuable indicator for the potential development of BPD.

Diagnostic Value of Pulmonary Ultrasound and Arterial Blood Gas Analysis in Acute Patients with Severe Injuries Complicated by Respiratory Failure-A Retrospective Study

Background

To investigate the early application of pulmonary ultrasonography and arterial blood gas analysis in critical patients with severe multiple injuries exacerbated by respiratory failure.

Patients and Methods

The retrospective selection was performed on 81 patients admitted to our critical care unit between January 2020 and January 2021 with severe multiple injuries rendered worse by respiratory failure. Based on the different examination procedures, the patients were categorised into three groups (n=27): group A; diagnosed with pulmonary ultrasonography, group B; diagnosed with arterial blood gas; and group C; diagnosed with both pulmonary ultrasonography and arterial blood gas analyses. Patients were subsequently divided into a survival group (n = 65) and a death group (n = 16). On an annual basis, patients' prognoses were examined in relation to the predictive value of pulmonary ultrasound.

Results

Initial diagnosis, diagnosis, and initial correct treatment times were significantly shorter in groups B and C than group A (P<0.05). In contrast, initial diagnosis time, diagnosis time, and initial correct treatment times were potentially shorter in group C than in group B (P<0.05). Compared to groups B and C, group A had a considerably lower diagnosis rate for the examination methods (P<0.05). The right diaphragm displacement and left diaphragm displacement in the survival group were potentially higher than the LUS score (P < 0.05). In contrast, the survival group's lung ultrasound score (LUS) was considerably lower than the death group's. Statistical analysis showed that the predictive values of right diaphragm displacement, left diaphragm displacement, and mean diaphragm displacement were significant compared with the LUS score. The findings of the receiver operating characteristic curve demonstrated that the right, left, and average diaphragm displacements had high predictive values.

Conclusion

In the early evaluation of patients with severe multiple injuries complicated by respiratory failure, pulmonary ultrasonography combined with arterial blood gas analysis is crucial for the rapid diagnosis and prognosis prediction of patients.

Modified lung ultrasound score for bronchopulmonary dysplasia predicts late respiratory outcomes in preterm infants

OBJECTIVE

Lung ultrasound (LUS) is a useful and radiation-free diagnostic tool for predicting bronchopulmonary dysplasia, which is a risk factor for late respiratory disease. However, data on the relationship of LUS with late respiratory disease was scarce. This study aims to determine whether LUS is associated with late respiratory disease during early childhood.

METHODS

This prospective cohort study enrolled preterm infants born before 32 weeks of gestation. LUS was performed at 36 weeks' postmenstrual age. The predictive values of a modified lung ultrasound (mLUS) score based on eight standard sections were assessed to predict late respiratory disease, defined as a physician diagnosis of bronchopulmonary dysplasia deterioration, asthma, reactive airway disease, bronchiolitis, pneumonia, or respiratory-related hospitalization during the first 2 years of life.

RESULTS

A total of 94 infants completed follow-up, of whom 74.5% met the late respiratory disease criteria. The mLUS scores were significantly associated with late respiratory disease (adjusted odds ratio: 1.23, CI: 1.10-1.38, p < 0.001). The mLUS scores also well predicted late respiratory disease (AUC = 0.820, 95% CI: 0.733-0.907). These scores were superior to the classic lung ultrasound score (p = 0.02) and as accurate as the modified NICHD-defined bronchopulmonary dysplasia classification (p = 0.91). A mLUS score ≥14 was the optimal cutoff point for predicting late respiratory disease.

CONCLUSION

The modified lung ultrasound score correlates significantly with late respiratory disease and well predicts it in preterm infants during the first 2 years of life.

Defining and Promoting Pediatric Pulmonary Health: Assessing Lung Function and Structure

Lifelong respiratory health is rooted in the structural and functional development of the respiratory system in early life. Exposures and interventions antenatally through childhood can influence lung development into young adulthood, the life stage with the highest achievable lung function. Because early respiratory health sets the stage for adult lung function trajectories and risk of developing chronic obstructive pulmonary disease, understanding how to promote lung health in children will have far reaching personal and population benefits. To achieve this, it is critical to have accurate and precise measures of structural and functional lung development that track throughout life stages. From this foundation, evaluation of environmental, genetic, metabolic, and immune mechanisms involved in healthy lung development can be investigated. These goals require the involvement of general pediatricians, pediatric subspecialists, patients, and researchers to design and implement studies that are broadly generalizable and applicable to otherwise healthy and chronic disease populations. This National Institutes of Health workshop report details the key gaps and opportunities regarding lung function and structure.

Lung ultrasound score predicts patent ductus arteriosus ligation among neonates ≤25 weeks

BACKGROUND

This prospective study aimed to investigate whether lung ultrasound score (LUSs) can predict the patent ductus arteriosus (PDA) ligation.

METHODS

Preterm infants ≤25 weeks of gestational age (GA) were enrolled. A lung ultrasound was performed on the 14th day of life. Each lung zone was given a score between 0 and 4. A receiver-operating characteristic (ROC) curve was constructed to evaluate the ability of the LUSs for predicting ligation.

RESULTS

A total of 81 infants were eligible with a median GA and birth weight (BW) of 25 weeks (24.1-25.2) and 710 g (645-770), respectively. The median time from birth to ligation was 35 days (32-51). Those who underwent ligation had a longer time of mechanical ventilation (34 [26-39] vs. 19 [12-30], p < 0.001), shorter time of noninvasive respiratory support (39 [32-51] vs. 50 [41.5-57], p < 0.01), higher incidence of the bronchopulmonary dysplasia (BPD) (p < 0.01), and severe BPD (p < 0.001). The LUSs had an area under the ROC of 0.96 (95% confidence interval: 0.93-0.99) for the prediction of ligation. A LUSs cutoff of 36 has a sensitivity and specificity of 96% and 86% and positive and negative predictive values of 82% and 98%, respectively.

CONCLUSIONS

LUSs at an early stage of life can predict PDA ligation in extremely preterm infants. It would be helpful to reduce morbidity by reducing the duration and magnitude of respiratory support.

Monitoring of the Healthy Neonatal Transition Period with Serial Lung Ultrasound

Ultrasound has been used to observe lung aeration and fluid clearance during the neonatal transition period, but there is no consensus regarding the optimal timing of lung ultrasound. We aimed to monitor the trend of the serial lung ultrasound score (LUS) and extended LUS (eLUS) throughout the neonatal transition period (≤1, 2, 4, 8, 24, and 48 h after birth), assess any correlation to the clinical presentation (using the Silverman Andersen Respiratory Severity Score (RSS)), and determine the optimal time of the ultrasound. We found both LUS and eLUS decreased significantly after 2 h of life and had similar statistical differences among the serial time points. Although both scores had a positive, moderate correlation to the RSS overall (Pearson correlation 0.499 [p < 0.001] between LUS and RSS, 0.504 [p < 0.001] between eLUS and RSS), the correlation was poor within 1 h of life (Pearson correlation 0.15 [p = 0.389] between LUS and RSS, 0.099 [p = 0.573] between eLUS and RSS). For better clinical correlation, the first lung ultrasound for the neonate may be performed at 2 h of life. Further research is warranted to explore the clinical value and limitations of earlier (≤1 h of life) lung ultrasound examinations.

Cardiorespiratory Monitoring Data to Predict Respiratory Outcomes in Extremely Preterm Infants

Rationale: Immature control of breathing is associated with apnea, periodic breathing, intermittent hypoxemia, and bradycardia in extremely preterm infants. However, it is not clear if such events independently predict worse respiratory outcome. Objectives: To determine if analysis of cardiorespiratory monitoring data can predict unfavorable respiratory outcomes at 40 weeks postmenstrual age (PMA) and other outcomes, such as bronchopulmonary dysplasia at 36 weeks PMA. Methods: The Prematurity-related Ventilatory Control (Pre-Vent) study was an observational multicenter prospective cohort study including infants born at <29 weeks of gestation with continuous cardiorespiratory monitoring. The primary outcome was either "favorable" (alive and previously discharged or inpatient and off respiratory medications/O2/support at 40 wk PMA) or "unfavorable" (either deceased or inpatient/previously discharged on respiratory medications/O2/support at 40 wk PMA). Measurements and Main Results: A total of 717 infants were evaluated (median birth weight, 850 g; gestation, 26.4 wk), 53.7% of whom had a favorable outcome and 46.3% of whom had an unfavorable outcome. Physiologic data predicted unfavorable outcome, with accuracy improving with advancing age (area under the curve, 0.79 at Day 7, 0.85 at Day 28 and 32 wk PMA). The physiologic variable that contributed most to prediction was intermittent hypoxemia with oxygen saturation as measured by pulse oximetry <90%. Models with clinical data alone or combining physiologic and clinical data also had good accuracy, with areas under the curve of 0.84-0.85 at Days 7 and 14 and 0.86-0.88 at Day 28 and 32 weeks PMA. Intermittent hypoxemia with oxygen saturation as measured by pulse oximetry <80% was the major physiologic predictor of severe bronchopulmonary dysplasia and death or mechanical ventilation at 40 weeks PMA. Conclusions: Physiologic data are independently associated with unfavorable respiratory outcome in extremely preterm infants.

Lung Ultrasound Induction of Pulmonary Capillary Hemorrhage in Rats With Consideration of Exposimetric Relationships to Previous Similar Observations in Neonatal Swine

OBJECTIVE

Lung ultrasound (LUS) has become an essential clinical tool for pulmonary evaluation. LUS has been found to induce pulmonary capillary hemorrhage (PCH) in animal models, posing a safety issue. The induction of PCH was investigated in rats, and exposimetry parameters were compared with those of a previous neonatal swine study.

METHODS

Female rats were anesthetized and scanned in a warmed water bath with the 3Sc, C1-5 and L4-12t probes from a GE Venue R1 point-of-care ultrasound machine. Acoustic outputs (AOs) of sham, 10%, 25%, 50% or 100% were applied for 5-min exposures with the scan plane aligned with an intercostal space. Hydrophone measurements were used to estimate the in situ mechanical index (MIIS) at the lung surface. Lung samples were scored for PCH area, and PCH volumes were estimated.

RESULTS

At 100% AO, the PCH areas were 73 ± 19 mm2 for the 3.3 MHz 3Sc probe (4 cm lung depth), 49 ± 20 mm2 (3.5 cm lung depth) or 96 ± 14 mm2 (2 cm lung depth) for the 3.0 MHz C1-5 probe and 7.8 ± 2.9 mm2 for the 7 MHz L4-12t (1.2 cm lung depth). Estimated volumes ranged from 378 ± 97 mm3 for the C1-5 at 2 cm to 1.3 ± 1.5 mm3 for the L4-12t. MIIS thresholds for PCH were 0.62, 0.56 and 0.48 for the 3Sc, C1-5 and L4-12t, respectively.

CONCLUSION

Comparison between this study and previous similar research in neonatal swine revealed the importance of chest wall attenuation. Neonatal patients may be most susceptible to LUS PCH because of thin chest walls.

Pulmonary Sonography - Neonatal Diagnosis Part 2

A healthy, air-filled lung can only be visualized by its artifacts, and pathologies of the lung are revealed by changes in these artifacts. Because ultrasound artifacts are predominantly used in pulmonary sonography to assess pathologic processes, the variability of sonographically imageable phenomena is limited. For this reason, different pulmonary diseases may present very similarly in ultrasound. Therefore, a correct interpretation of the findings is only possible in the clinical context, taking into account the age-dependent differential diagnoses.The particular relevance of lung ultrasound in the treatment of neonatal patients results from a close correlation between the extent of sonographically-depictable pathologies and parameters of respiratory insufficiency. This suggests a direct correlation between ultrasound findings and the severity of lung injury. Lung ultrasound thus represents a unique, ubiquitously available, bedside, serial method for monitoring the pulmonary status.

Early prediction of pulmonary outcomes in preterm infants using electrical impedance tomography

Introduction

Electrical impedance tomography (EIT) allows assessment of ventilation and aeration homogeneity which may be associated with respiratory outcomes in preterm infants.

Methods

This was a secondary analysis to a recent randomized controlled trial in very preterm infants in the delivery room (DR). The predictive value of various EIT parameters assessed 30 min after birth on important respiratory outcomes (early intubation <24 h after birth, oxygen dependency at 28 days after birth, and moderate/severe bronchopulmonary dysplasia; BPD) was assessed.

Results

Thirty-two infants were analyzed. A lower percentage of aerated lung volume [OR (95% CI) = 0.8 (0.66-0.98), p = 0.027] as well as a higher aeration homogeneity ratio (i.e., more aeration in the non-gravity-dependent lung) predicted the need for supplemental oxygen at 28 days after birth [9.58 (5.16-17.78), p = 0.0028]. Both variables together had a similar predictive value to a model using known clinical contributors. There was no association with intubation or BPD, where numbers were small.

Discussion

In very preterm infants, EIT markers of aeration at 30 min after birth accurately predicted the need for supplemental oxygen at 28 days after birth but not BPD. EIT-guided individualized optimization of respiratory support in the DR may be possible.

Prediction of respiratory distress severity and bronchopulmonary dysplasia by lung ultrasounds and transthoracic electrical bioimpedance

This study aims to evaluate whether the assessment of a lung ultrasound score (LUS) by lung ultrasonography and of thoracic fluid contents (TFC) by electrical cardiometry may predict RDS severity and the development of bronchopulmonary dysplasia (BPD) in preterm infants with respiratory distress (RDS). Infants ≤ 34 weeks' gestation admitted with RDS to two neonatal intensive care units were prospectively enrolled in this observational study. A simultaneous evaluation of LUS and TFC was performed during the first 72 h. The predictivity of LUS and TFC towards mechanical ventilation (MV) need after 24 h and BPD development was evaluated using receiver operating characteristic analysis. Sixty-four infants were included. The area under the curve (AUC) for the prediction of MV need was 0.851 (95%CI, 0.776-0.925, p < 0.001) for LUS and 0.793 (95%CI, 0.724-0.862, p < 0.001) for TFC, while an AUC of 0.876 (95%CI, 0.807-0.946, p < 0.001) was obtained for combined LUS and TFC evaluation. LUS and TFC AUC for BPD prediction were 0.769 (95%CI, 0.697-0.842, p < 0.001) and 0.836 (95%CI, 0.778-0.894, p < 0.001), respectively, whereas their combined assessment yielded an AUC of 0.867 (95%CI, 0.814-0.919, p < 0.001). LUS ≥ 11 and TFC ≥ 40 were identified as cut-off values for MV need prediction, whereas LUS ≥ 9 and TFC ≥ 41.4 best predicted BPD development.   Conclusion: A combined evaluation of LUS and TFC by lung ultrasonography and EC during the first 72 h may represent a useful predictive tool towards short- and medium-term pulmonary outcomes in preterm infants with RDS. What is Known: • Lung ultrasonography is largely used in neonatal intensive care and can contribute to RDS diagnosis in preterm infants. • Little is known on the diagnostic and predictive role of TFC, measured by transthoracic electrical bioimpedance, in neonatal RDS. What is New: • Combining lung ultrasonography and TFC evaluation during the first 72 h can improve the prediction of RDS severity and BPD development in preterm infants with RDS and may aid to establish tailored respiratory approaches to improve these outcomes.

Use of Cardio-Pulmonary Ultrasound in the Neonatal Intensive Care Unit

Cardiopulmonary ultrasound (CPUS), the combination of lung ultrasound (LUS) and targeted neonatal echocardiography (TnECHO)AA, may offer a more appropriate approach to the challenging neonatal cardiovascular and respiratory disorders. This paper reviews the possible use of CPUS in the neonatal intensive care unit (NICU).

Prematurity and BPD: what general pediatricians should know

More and more very low birth weight (VLBW) infants around the world survive nowadays, with consequently larger numbers of children developing prematurity-related morbidities, especially bronchopulmonary dysplasia (BPD). BPD is a multifactorial disease and its rising incidence in recent years means that general pediatricians are much more likely to encounter a child born extremely preterm, possibly with BPD, in their clinical practice. Short- and long-term sequelae in VLBW patients may affect not only pulmonary function (principally characterized by an obstructive pattern), but also other aspect including the neurological (neurodevelopmental and neuropsychiatric disorders), the sensorial (earing and visual impairment), the cardiological (systemic and pulmonary hypertension, reduced exercise tolerance and ischemic heart disease in adult age), nutritional (feeding difficulties and nutritional deficits), and auxological (extrauterine growth restriction). For the most premature infants at least, a multidisciplinary follow-up is warranted after discharge from the neonatal intensive care unit in order to optimize their respiratory and neurocognitive potential, and prevent respiratory infections, nutritional deficiencies or cardiovascular impairments.  Conclusion: The aim of this review is to summarize the main characteristics of preterm and BPD infants, providing the general pediatrician with practical information regarding these patients' multidisciplinary complex follow-up. We explore the current evidence on respiratory outcomes and their management that actually does not have a definitive available option. We also discuss the available investigations, treatments, and strategies for prevention and prophylaxis to improve the non-respiratory outcomes and the quality of life for these children and their families, a critical aspect not always considered. This comprehensive approach, added to the increased needs of a VLBW subjects, is obviously related to very high health-related costs that should be beared in mind. What is Known: • Every day, a general pediatrician is more likely to encounter a former very low birth weight infant. • Very low birth weight and prematurity are frequently related not only with worse respiratory outcomes, but also with neurological, sensorial, cardiovascular, renal, and nutritional issues. What is New: • This review provides to the general pediatrician a comprehensive approach for the follow-up of former premature very low birth weight children, with information to improve the quality of life of this special population.

Comparison of lung ultrasound scores with clinical models for predicting bronchopulmonary dysplasia

Lung ultrasound scores (LUSs) have been demonstrated to accurately predict moderate-to-severe bronchopulmonary dysplasia (msBPD). This study attempted to explore the additional value of LUSs for predicting msBPD compared to clinical multivariate models in different gestational age (GA) groups. The study prospectively recruited preterm infants with GA < 32 weeks. Lung ultrasound was performed on days 3, 7, 14, and 21 after birth. A linear mixed-effects regression model was used to evaluate LUS evolution in infants born before and after 28 weeks. The receiver operating characteristic (ROC) procedure was used to analyze the reliability of LUS and clinical multivariable models for predicting msBPD. The optimal time to predict msBPD in all infants was 7 days with a cut-off point of 5 (area under the ROC (AUROC) curve: 0.78, 95% confidence interval (CI): 0.71-0.84). In infants with GA ≥ 28 weeks, LUSs provided a moderate diagnostic accuracy for all four time points (AUROC curve: 0.74-0.78), and the AUROC curve for the clinical multivariable model on day 14 was 0.91 (95% CI: 0.84-0.96), which was significantly higher than that of LUSs (AUROC curve: 0.77, 95% CI: 0.68-0.85, P < 0.05). In infants born at 23-27 weeks, LUSs showed a low diagnostic accuracy with higher cut-off points to predict msBPD, and the AUROC curve for GA to predict msBPD was 0.75 (95% CI: 0.59-0.85), providing diagnostic accuracy similar to that of LUSs.  Conclusion: The contribution of LUSs to predict msBPD in infants with different GAs remains controversial and requires further investigation. What is Known: • Lung ultrasound scores (LUSs) have been demonstrated to accurately predict moderate-to-severe bronchopulmonary dysplasia in infants with gestational age (GA)＜32 weeks. What is New: • The LUSs evolution differed between extremely preterm infants born before 28 weeks and preterm infants born at 28-32 weeks of gestation. • LUSs provided similar moderate predictive performance as GA-adjusted LUS and clinical multivariate models in infants born after 28 weeks, while LUSs seem to be less helpful in infants born before 28 weeks.

Diaphragmatic Thickness and Excursion in Preterm Infants With Bronchopulmonary Dysplasia Compared With Term or Near Term Infants: A Prospective Observational Study

BACKGROUND

Diaphragmatic atrophy associated with mechanical ventilation is reported in pediatric and adult patients, but a similar association has not been described in preterm infants with bronchopulmonary dysplasia (BPD).

RESEARCH QUESTION

Does BPD impact the diaphragm thickness (DT) and diaphragm excursion (DE) in infants born before 32 weeks' gestation compared with healthy late preterm or term infants?

STUDY DESIGN AND METHODS

In this prospective observational case-control study, DT at end of expiration (DT_exp), DT at end of inspiration (DT_ins), DT fraction (DTF), and DE (DE) were assessed using bedside ultrasound. Two groups were compared: infants with BPD (patients) and healthy, postmenstrual age-matched infants (control participants). To account for variations in body size between groups, diaphragmatic measurements were expressed as a ratio of body surface area (BSA). Statistical analyses were conducted using SAS software version 9.4 (SAS Institute, Inc.).

RESULTS

We enrolled 111 infants, including 56 preterm infants with BPD (mean ± SD study age, 37.7 ± 1.7 weeks) and 55 healthy control participants (mean ± SD study age, 38.1 ± 1.5 weeks). DT_exp and DT_exp to BSA ratio were significantly lower in the BPD group compared with the healthy control group (mean ± SD, 1.3 ± 0.4 mm vs 1.5 ± 0.4 mm [P = .01] and 7.1 ± 1.4 mm/m² vs 7.8 ± 1.8 mm/m² [P = .03]). DTF and DE were significantly higher in the BPD group vs the healthy control group (mean ± SD, 61.8 ± 26.0 vs 43.3 ± 19.7 [P < .01] and 6.0 ± 1.7 mm vs 4.4 ± 1.6 mm [P < .01], respectively).

INTERPRETATION

In infants with BPD, DT_exp was significantly lower, whereas DTF and DE were significantly higher, compared with healthy, age-matched control participants. Future studies are required and should focus on describing the evolution of diaphragmatic dimensions in preterm infants with and without BPD.

TRIAL REGISTRY

ClinicalTrials.gov; No.: NCT04941963; URL: www.

CLINICALTRIALS

gov.

Lung ultrasound in neonates - An underused tool

Point of care lung ultrasound (USG) can help in the diagnosis and management of critically sick neonates. It is based on seven simple principles that are comprehensive enough to diagnose all major lung pathologies. A compact small machine and a micro-convex or linear probe are the basic requirements to perform lung USG. In contrast to traditional USG principles, USG of the lung is based on artefacts. Some of the terminologies that are used to characterize normal lung include the pleural line, A-line, bat sign, lung sliding and seashore sign. Air/fluid mixture in varying ratios helps in diagnosis of normal lung, pneumothorax, interstitial syndrome (transient tachypnoea of newborn, respiratory distress syndrome, bronchopulmonary dysplasia), lung consolidation and pleural effusion.

Respiratory and haemodynamic effects of 6h-pronation in neonates recovering from respiratory distress syndrome, or affected by acute respiratory distress syndrome or evolving bronchopulmonary dysplasia: a prospective, physiological, crossover, controlled cohort study

BACKGROUND

Pronation ameliorates oxygenation in adults with acute respiratory distress syndrome (ARDS); the effect in neonates with ARDS or other types of respiratory failure is unknown. We aimed to verify if pronation has similar respiratory and haemodynamic effects in three common types of neonatal respiratory failure.

METHODS

Prospective, physiologic, crossover, quasi-randomised, controlled cohort study performed in a tertiary academic neonatal intensive care unit. We enrolled neonates with: 1) recovering respiratory distress syndrome (RDS, mild restrictive pattern); 2) neonatal ARDS (NARDS, severe restrictive pattern); or 3) evolving bronchopulmonary dysplasia (BPD), that is chronic pulmonary insufficiency of prematurity (mixed restrictive/obstructive pattern). Neonates with other lung disorders, malformations or haemodynamic impairment were excluded. Patients were started prone or supine and then shifted to the alternate position for 6h; measurements were performed after 30' of "wash out" from the positioning and at the end of 6h period. Primary outcomes were respiratory (PtcCO_2, modified ventilatory index, PtcO₂/FiO₂, SpO₂/FiO₂, oxygenation index, ultrasound-assessed lung aeration) and haemodynamic (perfusion index, heart rate, arterial pressure, cardiac output) parameters.

FINDINGS

Between May 1st, 2019, and May 31st, 2021, 161 participants were enrolled in this study, and included in the final analysis. Pronation improved gas exchange and lung aeration (p always <0.01) and these effects were overturned in the alternate position, except for lung aeration in NARDS where the improvement persisted. The effects were greater in patients recovering from RDS than in those with evolving BPD than in those with NARDS, in this order (p always <0.01). Pronation produced a net recruitment as lung ultrasound score decreased in patients shifted from supine (16.9 (standard deviation: 5.8)) to prone (14.1 (standard deviation: 3.3), p < 0.01) and this reduction correlated with oxygenation improvement. Haemodynamic parameters remained within normal ranges.

INTERPRETATION

6h-pronation can be used to improve gas exchange and lung aeration in neonates with recovering RDS, evolving BPD or NARDS without relevant haemodynamic effects.

FUNDING

None.

Ultrasonographic assessment of diaphragmatic function in preterm infants on non-invasive neurally adjusted ventilatory assist (NIV-NAVA) compared to nasal intermittent positive-pressure ventilation (NIPPV): a prospective observational study

NIV-NAVA mode for respiratory support in preterm infants is not well-studied. This study aimed to describe the diaphragmatic function, diaphragmatic excursion (DE), and thickness fraction (DTF), in preterm infants < 30 weeks' gestation supported by NIV-NAVA compared to NIPPV using bedside ultrasonography. In this consecutive prospective study, DE, diaphragmatic thickness at end of expiration (DT_exp), end of inspiration (DT_ins), and DTF were assessed using bedside ultrasound. Lung aeration evaluation using lung ultrasound score (LUS) was performed for the two groups. Diaphragmatic measurements and LUS were compared for the 2 groups (NIV-NAVA group versus NIPPV group). Statistical analyses were conducted using the SPSS software version 22. Out of 70 infants evaluated, 40 were enrolled. Twenty infants were on NIV-NAVA and 20 infants on NIPPV with a mean [SD] study age of 25.7 [0.9] weeks and 25.1 [1.4] weeks respectively (p = 0.15). Baseline characteristics and respiratory parameters at the time of the scan showed no significant difference between groups. DE was significantly higher in NIV-NAVA with a mean SD of 4.7 (1.5) mm versus 3.5 (0.9) mm in NIPPV, p = 0.007. Additionally, the mean (SD) of DTF for the NIV-NAVA group was 81.6 (30) % vs 78.2 (27) % for the NIPPV group [p = 0.71]. Both groups showed relatively high LUS but no significant difference between groups [12.8 (2.6) vs 12.6 (2.6), p = 0.8].  Conclusion: Preterm infants managed with NIV-NAVA showed significantly higher DE compared to those managed on NIPPV. This study raises the hypothesis that NIV-NAVA could potentially improve diaphragmatic function due to its synchronization with patients' own breathing. Longitudinal studies to assess diaphragmatic function over time are needed.  Trial registry: Clinicaltrials.gov (NCT05079412). Date of registration September 30, 2021. What is Known: • NIV-NAVA utilizes diaphragmatic electrical activity to provide synchronized breathing support. • Evidence for the effect of NIV-NAVA on diaphragmatic thickness fraction (DTF) and excursion (DE) is limited. What is New: • Ultrasonographic assessment of diaphragmatic function (DTF and DE) is feasible. • In preterm infants, DE was significantly higher in infants supported with NIV-NAVA compared to those supported with NIPPV.

A scoping review of echocardiographic and lung ultrasound biomarkers of bronchopulmonary dysplasia in preterm infants

Despite recent improvements in neonatal care, moderate to severe bronchopulmonary dysplasia (BPD) is still associated with high mortality and with an increased risk of developing pulmonary hypertension (PH). This scoping review provides an updated overview of echocardiographic and lung ultrasound biomarkers associated with BPD and PH, and the parameters that may prognosticate their development and severity, which could be clinically helpful to undertake preventive strategies. A literature search for published clinical studies was conducted in PubMed using MeSH terms, free-text words, and their combinations obtained through appropriate Boolean operators. It was found that the echocardiography biomarkers for BPD, and especially those assessing right ventricular function, are reflective of the high pulmonary vascular resistance and PH, indicating a strong interplay between heart and lung pathophysiology; however, early assessment (e.g., during the first 1-2 weeks of life) may not successfully predict later BPD development. Lung ultrasound indicating poor lung aeration at day 7 after birth has been reported to be highly predictive of later development of BPD at 36 weeks' postmenstrual age. Evidence of PH in BPD infants increases risk of mortality and long-term PH; hence, routine PH surveillance in all at risk preterm infants at 36 weeks, including an echocardiographic assessment, may provide useful information. Progress has been made in identifying the echocardiographic parameters on day 7 and 14 to predict later development of pulmonary hypertension. More studies on sonographic markers, and especially on echocardiographic parameters, are needed for the validation of the currently proposed parameters and the timing of assessment before recommendations can be made for the routine clinical practice.

Clinical practice guidelines: management of severe bronchiolitis in infants under 12 months old admitted to a pediatric critical care unit

PURPOSE

We present guidelines for the management of infants under 12 months of age with severe bronchiolitis with the aim of creating a series of pragmatic recommendations for a patient subgroup that is poorly individualized in national and international guidelines.

METHODS

Twenty-five French-speaking experts, all members of the Groupe Francophone de Réanimation et Urgence Pédiatriques (French-speaking group of paediatric intensive and emergency care; GFRUP) (Algeria, Belgium, Canada, France, Switzerland), collaborated from 2021 to 2022 through teleconferences and face-to-face meetings. The guidelines cover five areas: (1) criteria for admission to a pediatric critical care unit, (2) environment and monitoring, (3) feeding and hydration, (4) ventilatory support and (5) adjuvant therapies. The questions were written in the Patient-Intervention-Comparison-Outcome (PICO) format. An extensive Anglophone and Francophone literature search indexed in the MEDLINE database via PubMed, Web of Science, Cochrane and Embase was performed using pre-established keywords. The texts were analyzed and classified according to the Grading of Recommendations Assessment, Development and Evaluation (GRADE) methodology. When this method did not apply, an expert opinion was given. Each of these recommendations was voted on by all the experts according to the Delphi methodology.

RESULTS

This group proposes 40 recommendations. The GRADE methodology could be applied for 17 of them (3 strong, 14 conditional) and an expert opinion was given for the remaining 23. All received strong approval during the first round of voting.

CONCLUSION

These guidelines cover the different aspects in the management of severe bronchiolitis in infants admitted to pediatric critical care units. Compared to the different ways to manage patients with severe bronchiolitis described in the literature, our original work proposes an overall less invasive approach in terms of monitoring and treatment.

Lung ultrasound of the dependent lung detects real-time changes in lung volume in the preterm lamb

BACKGROUND

Effective lung protective ventilation requires reliable, real-time estimation of lung volume at the bedside. Neonatal clinicians lack a readily available imaging tool for this purpose.

OBJECTIVE

To determine the ability of lung ultrasound (LUS) of the dependent region to detect real-time changes in lung volume, identify opening and closing pressures of the lung, and detect pulmonary hysteresis.

METHODS

LUS was performed on preterm lambs (n=20) during in vivo mapping of the pressure-volume relationship of the respiratory system using the super-syringe method. Electrical impedance tomography was used to derive regional lung volumes. Images were blindly graded using an expanded scoring system. The scores were compared with total and regional lung volumes, and differences in LUS scores between pressure increments were calculated.

RESULTS

Changes in LUS scores correlated moderately with changes in total lung volume (r=0.56, 95% CI 0.47-0.64, p<0.0001) and fairly with right whole (r=0.41, CI 0.30-0.51, p<0.0001), ventral (r=0.39, CI 0.28-0.49, p<0.0001), central (r=0.41, CI 0.31-0.52, p<0.0001) and dorsal (r=0.38, CI 0.27-0.49, p<0.0001) regional lung volumes. The pressure-volume relationship of the lung exhibited hysteresis in all lambs. LUS was able to detect hysteresis in 17 (85%) lambs. The greatest changes in LUS scores occurred at the opening and closing pressures.

CONCLUSION

LUS was able to detect large changes in total and regional lung volume in real time and correctly identified opening and closing pressures but lacked the precision to detect small changes in lung volume. Further work is needed to improve precision prior to translation to clinical practice.

Intravitreal Bevacizumab Is Associated With Prolonged Ventilatory Support in Preterm Infants With Bronchopulmonary Dysplasia

BACKGROUND

Intravitreal bevacizumab (IVB), an anti-vascular endothelial growth factor (VEGF) antibody, is a widely adopted treatment for retinopathy of prematurity (ROP). Although animal studies have demonstrated that IVB inhibits alveologenesis in neonatal rat lung, the clinical influence of IVB on respiratory outcomes has not been studied.

RESEARCH QUESTION

Does IVB affect the respiratory outcome in preterm infants with bronchopulmonary dysplasia?

STUDY DESIGN AND METHODS

We retrospectively assessed very low birth weight (VLBW) preterm infants admitted to our neonatal ICU between January 2016 and June 2021. Furthermore, we evaluated the short-term respiratory outcomes after IVB therapy in VLBW preterm infants requiring ventilatory support at 36 weeks' postmenstrual age (PMA).

RESULTS

One hundred seventy-four VLBW preterm infants with bronchopulmonary dysplasia were recruited. Eighty-eight infants showed ROP onset before being ventilator free, and 78 infants received a diagnosis of the most severe ROP before being ventilator free. Among them, 32 received a diagnosis with type 1 ROP and received IVB treatment. After adjusting for gestational age, birth body weight, and baseline respiratory status, we discovered that IVB is associated significantly with prolonged ventilatory support and a lower likelihood of becoming ventilator free (hazard ratio, 0.53; P = .03).

INTERPRETATION

IVB may have a short-term respiratory adverse effect in patients requiring ventilatory support at 36 weeks' PMA. Therefore, long-term follow-up for respiratory outcomes may be considered in VLBW infants who receive IVB treatment.

Lung ultrasound score follows the chronic pulmonary insufficiency of prematurity trajectory in early infancy

Extremely preterm birth is associated with a high risk of chronic pulmonary insufficiency of prematurity (CPIP). Lung ultrasound score (LUS) proved capable to characterise CPIP progression beyond the acute setting, but still, post-discharge data remain lacking. We hypothesised a priori that LUS in both BPD and no-BPD infants declines with postnatal age from birth through early infancy. This observational retrospective cohort study included preterm infants < 32 gestational weeks, who underwent the follow-up for CPIP. LUS was assessed from birth to 8 months postnatal age, over antero-lateral (LUS) and posterior (pLUS) pulmonary areas, placing the transducer longitudinally over the midclavicular and midaxillary lines and medial to the scapular line respectively. Extended LUS (eLUS) including LUS and pLUS was calculated. The primary outcome was LUS time course. Secondary outcomes included the correlation between LUS and pLUS. Sixty-two infants were included: 22 (35.5%) in the BPD group and 40 (64.5%) in the no-BPD group. BPD group infants were smaller (weight 841 g (± 228) vs 1226 (± 328), p < 0.001) and younger (26.8 weeks (± 2.0) vs 28.9 (± 1.9), p < 0.001). LUS declined over time in the entire population (ß =  - 1.75, p < 0.001) and in both no-BPD and BPD groups (ß =  - 1.64, p < 0.001 and ß =  - 1.93, p < 0.001, respectively). eLUS declined correspondingly (p < 0.001). LUS and likewise eLUS were significantly different between BPD and no-BPD groups over time (p < 0.001).  Conclusion: LUS trajectory progressively decreased from birth to early infancy. BPD cohort tracked higher, implying a worse respiratory status. pLUS had a similar timepoint course, adding no further information to LUS. To the best of our knowledge, this is the first study that describes preterm LUS time course after discharge. LUS may help track the CPIP progression. What is Known: • Extremely preterm birth is associated with high risk of chronic pulmonary insufficiency of prematurity (CPIP). • Several studies investigated the ability of lung ultrasound score (LUS) to characterize CPIP progression beyond the acute setting, still post-discharge data remain lacking. What is New: • LUS trajectory progressively decreases from birth to early infancy; BPD cohort tracks higher, implying a worse respiratory status. pLUS has similar timepoint course, adding no further information to LUS. • The use of LUS may contribute to better characterising and monitoring CPIP in BPD and no-BPD infants.

Bronchopulmonary dysplasia: Can we provide a link between prenatal and postnatal lung ultrasound?

The role of lung ultrasound in the prediction of bronchopulmonary dysplasia.

Lung ultrasound findings in asymptomatic healthy children with asthma

BACKGROUND

Lung ultrasound (LUS) has been shown to be an effective tool to rapidly diagnose certain causes of pediatric respiratory distress. However, very little is known about LUS findings in pediatric asthma.

OBJECTIVES

The primary objective of this study was to characterize LUS findings in a cohort of pediatric patients with a definitive diagnosis of asthma, outside of an asthma exacerbation.

METHODS

Eligible patients, aged 6-17 years old and diagnosed with asthma, underwent LUS during an outpatient visit. LUS was conducted using a six-zone scanning protocol. Presence of a LUS artifact was defined by one or more of the following: ≥3 B-lines per intercostal space, pulmonary consolidation, and/or pleural abnormality. Images were interpreted by an expert sonographer blinded to patient clinical characteristics.

RESULTS

Fifty-two patients were included. 10/52 (19.2%) patients demonstrated the presence of LUS artifacts: 8 with ≥3 B-lines, 1 with consolidation >1 cm, and 7 with subpleural consolidations <1 cm, 1 with a pleural line abnormality. Artifacts were seen in the right anterior and lateral zones in 60% of participants and were limited to 1-2 intercostal space(s) within one lung zone in all participants. No association was found between presence of LUS artifacts and asthma control or severity.

CONCLUSION

To our knowledge, this is the first report of LUS findings in outpatient pediatric asthma. LUS artifacts in asthmatic children can be seen outside of acute exacerbations. Such baseline findings need to be taken into consideration when using LUS for the acute evaluation of a pediatric patient with asthma.

Quantitative lung ultrasound detects dynamic changes in lung recruitment in the preterm lamb

BACKGROUND

Lung ultrasound (LUS) may not detect small, dynamic changes in lung volume. Mean greyscale measurement using computer-assisted image analysis (Q-LUS_MGV) may improve the precision of these measurements.

METHODS

Preterm lambs (n = 40) underwent LUS of the dependent or non-dependent lung during static pressure-volume curve mapping. Total and regional lung volumes were determined using the super-syringe technique and electrical impedance tomography. Q-LUS_MGV and gold standard measurements of lung volume were compared in 520 images.

RESULTS

Dependent Q-LUS_MGV moderately correlated with total lung volume (rho = 0.60, 95% CI 0.51-0.67) and fairly with right whole (rho = 0.39, 0.27-0.49), central (rho = 0.38, 0.27-0.48), ventral (rho = 0.41, 0.31-0.51) and dorsal regional lung volumes (rho = 0.32, 0.21-0.43). Non-dependent Q-LUS_MGV moderately correlated with total lung volume (rho = 0.57, 0.48-0.65) and fairly with right whole (rho = 0.43, 0.32-0.52), central (rho = 0.46, 0.35-0.55), ventral (rho = 0.36, 0.25-0.47) and dorsal lung volumes (rho = 0.36, 0.25-0.47). All correlation coefficients were statistically significant. Distinct inflation and deflation limbs, and sonographic pulmonary hysteresis occurred in 95% of lambs. The greatest changes in Q-LUS_MGV occurred at the opening and closing pressures.

CONCLUSION

Q-LUS_MGV detected changes in total and regional lung volume and offers objective quantification of LUS images, and may improve bedside discrimination of real-time changes in lung volume.

IMPACT

Lung ultrasound (LUS) offers continuous, radiation-free imaging that may play a role in assessing lung recruitment but may not detect small changes in lung volume. Mean greyscale image analysis using computer-assisted quantitative LUS (Q-LUS_MGV) moderately correlated with changes in total and regional lung volume. Q-LUS_MGV identified opening and closing pressure and pulmonary hysteresis in 95% of lambs. Computer-assisted image analysis may enhance LUS estimation of lung recruitment at the bedside. Future research should focus on improving precision prior to clinical translation.

Lung ultrasound in Italian neonatal intensive care units: A national survey

INTRODUCTION

Lung ultrasound (LU) is a noninvasive, bedside imaging technique that is attracting growing interest in the evaluation of neonatal respiratory diseases. We conducted a nationwide survey of LU usage in Italian neonatal intensive care units (NICUs).

METHODS

A structured questionnaire was developed and sent online to 114 Italian NICUs from June to September 2021.

RESULTS

The response rate was 79%. In the past 4 years (range: 2-6), LU has been adopted in 82% of Italian NICUs. It is the first-choice diagnostic test in 23% of the centers surveyed. The main LU diagnostic applications reported were: pneumothorax (95%), respiratory distress syndrome (89%), transient tachypnea of the newborn (89%), plural effusion (88%), atelectasis (66%), pneumonia (64%), bronchopulmonary dysplasia (43%), congenital pulmonary airway malformation (41%), and congenital diaphragmatic hernia (34%). Thirty percent of participating centers calculated LU score routinely, but only seven units used it to predict the need for surfactant replacement. Sixty-six percent of respondents learned the LU technique via a self-training process, while 34% of them visited an expert in the field for one-to-one tuition.

CONCLUSIONS

LU has a widespread use in Italian NICUs. However, the use of LU is extremely heterogeneous among centers. There is an urgent need to ensure standardization of clinical practice guidelines and to design and implement a formalized and accredited training program.