Point-of-care lung ultrasound in neonatology: classification into descriptive and functional applications

Unnecessary radiation exposure during diagnostic radiography in infants in a neonatal intensive care unit: a retrospective cohort study

Unnecessary radiation exposure (URE) during radiographic examination is an issue among infants in neonatal intensive care units (NICUs). The causes of URE have not been fully explored. This study investigated the incidence and identified the causes of URE in infants during diagnostic radiography in a NICU. This was a retrospective cohort study. We retrieved and analysed requests and radiographs taken at a tertiary NICU between September and November 2018. URE was defined as the rate of discordance between requests and images taken (DisBRI) and unnecessary radiation exposure in irrelevant regions (UREIR) during radiography. We compared the rates of URE between very low-birth-weight (VLBW, birth weight < 1500 g) infants and non-VLBW infants. A total of 306 radiographs from 88 infants were taken. The means ± standard deviations (SDs) of gestational age and birth weight were 35.7 ± 3.6 weeks and 2471 ± 816 g, respectively. Each infant underwent an average of 3.5 radiographs. The DisBRI rate was 1.3% and was mostly related to poor adherence to requests. The UREIR rates in thoraco-abdominal babygrams were 89.6% for the head, 14.8% for the elbows and 18.4% for the knee and were mainly related to improper positioning of and collimation in infants while performing radiography. The UREIR rates for the head, knee and ankle were higher in VLBW infants than in non-VLBW infants (94.6% vs. 85.6%, 27.0% vs. 11.5% and 5.4% vs. 0.7%, respectively, p < 0.05).

CONCLUSIONS

URE during diagnostic radiography is common in sick infants and is mainly related to improper positioning and collimation during examinations. Adherence to protocols when performing radiographic examination or using ultrasonography may be a solution to reduce URE in infants in NICUs.

WHAT IS KNOWN

• The risk of unnecessary radiation exposure (URE) during radiography has been a common and important issue in sick infants in neonatal intensive care units (NICUs). • The new point-of-care ultrasound (POCUS) technique decreases the need for chest films and prevents radiation exposure in neonates.

WHAT IS NEW

• In the NICU, URE is still a common issue in critically ill infants during radiographic examinations. The causes of URE during diagnostic radiography are mainly due to improper positioning and collimation during examinations. • The incidence of URE in irrelevant regions is higher in very low-birth-weight (VLBW) infants than in non-VLBW infants.

Evolution of Ultrasound-Assessed Lung Aeration and Gas Exchange in Respiratory Distress Syndrome and Transient Tachypnea of the Neonate

OBJECTIVE

To use clinical, lung ultrasound, and gas exchange data to clarify the evolution of lung aeration and function in neonates with respiratory distress syndrome (RDS) and transient tachypnea of the neonate (TTN), the most common types of neonatal respiratory failure.

STUDY DESIGN

In this prospective observational cohort study, lung aeration and function were measured with a semiquantitative lung ultrasound score (LUS) and transcutaneous blood gas measurement performed at 1 hour (time point 0), 6 hours (time point 1), 12 hours (time point 2), 24 hours (time point 3) and 72 hours (time point 4) of life. Endogenous surfactant was estimated using lamellar body count (LBC). LUS, oxygenation index (OI), oxygen saturation index (OSI), and transcutaneous pressure of carbon dioxide (PtcCO₂) were the primary outcomes. All results were adjusted for gestational age.

RESULTS

Sixty-nine neonates were enrolled in the RDS cohort, and 58 neonates were enrolled in the TTN cohort. LUS improved over time (within-subjects, P < .001) but was worse for the RDS cohort than for the TTN cohort at all time points (between-subjects, P < .001). Oxygenation improved over time (within-subjects, P = .011 for OI, P < .001 for OSI) but was worse for the RDS cohort than for the TTN cohort at all time points (between-subjects, P < .001 for OI and OSI). PtcCO₂ improved over time (within-subjects, P < .001) and was similar in the RDS and TTN cohorts at all time points. Results were unchanged after adjustment for gestational age. LBC was associated with RDS (β = -0.2 [95% CI, -0.004 to -0.0001]; P = .037) and LUS (β = -3 [95% CI, -5.5 to -0.5]; P = .019).

CONCLUSIONS

For the first 72 hours of life, the RDS cohort had worse lung aeration and oxygenation compared with the TTN cohort at all time points. CO₂ clearance did not differ between the cohorts, whereas both lung aeration and function improved in the first 72 hours of life.

The Essentials about Neonatal Severe Acute Respiratory Syndrome Coronavirus 2 Infection and Coronavirus Disease: A Narrative Review

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection can occur in neonates as the virus can be transmitted both horizontally (from the environment) and vertically (during the pregnancy or at the delivery). Compared to the adult outbreak, neonatal infections do not represent a public health problem. Nonetheless, severe and life-threatening cases may rarely occur and both obstetricians and neonatologists should have a good knowledge of perinatal SARS-CoV-2 infection and related consequences. A high suspicion index must be applied and ruling out neonatal SARS-CoV-2 infection must become a part of the routine clinical workout. Moreover, neonates may be affected by the multisystem inflammatory syndrome, due to a dysregulated host response in the absence of any SARS-CoV-2 infection. We performed a narrative review to summarize here the available literature describing the essentials that should be known by every neonatologist and obstetrician, starting from what has been discovered in 2020 and adding what has been learned in the following years. The paper describes the mechanisms of transmission, clinical features, diagnostic tools, and criteria, as well as possible treatment and prevention strategies. The goal is to provide the practical points to be remembered at the bedside while caring for a pregnant woman or a neonate with suspected or proven coronavirus disease 2019 or multisystem inflammatory syndrome. KEY POINTS: · SARS-CoV-2 neonatal infections occur both vertically (30%) and horizontally (70%).. · Approximately, half of patients do not have clinical manifestations; clinical and laboratory signs are similar to those of adults but usually milder.. · Remdesivir and steroids can be used as a 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.

Use of Point-of-Care Ultrasonography in the NICU for Diagnostic and Procedural Purposes

Point-of-care ultrasonography (POCUS) refers to the use of portable imaging performed by the provider clinician at the bedside for diagnostic, therapeutic, and procedural purposes. POCUS could be considered an extension of the physical examination but not a substitute for diagnostic imaging. Use of POCUS in emergency situations can be lifesaving in the NICU if performed in a timely fashion for cardiac tamponade, pleural effusions, pneumothorax, etc, with potential for enhancing quality of care and improving outcomes.

In the past 2 decades, POCUS has gained significant acceptance in clinical medicine in many parts of the world and in many subspecialties. Formal accredited training and certification programs are available for neonatology trainees as well as for many other subspecialties in Canada, Australia, and New Zealand. Although no formal training program or certification is available to neonatologists in Europe, POCUS is widely available to providers in NICUs. A formal institutional POCUS fellowship is now available in Canada. In the United States, many clinicians have the skills to perform POCUS and have incorporated it in their daily clinical practice. However, appropriate equipment remains limited, and many barriers exist to POCUS program implementation.

Recently, the first international evidence-based POCUS guidelines for use in neonatology and pediatric critical care were published. Considering the potential benefits, a recent national survey of neonatologists confirmed that the majority of clinicians were inclined to adopt POCUS in their clinical practice if the barriers could be resolved.

This technical report describes many potential POCUS applications in the NICU for diagnostic and procedural purposes.

Lung ultrasound to evaluate lung recruitment in neonates with respiratory distress (RELUS study)

BACKGROUND

Lung ultrasound (LUS) is a bedside tool useful to diagnose neonatal respiratory disease and to guide surfactant therapy. LUS scores have emerged as useful tool for newborn respiratory distress but is unknown if respiratory support settings may influence it. The aim of the study was to evaluate the feasibility of LUS scores evaluating lung recruitment in term newborns with respiratory distress when noninvasive respiratory it is increased.

MATERIAL AND METHODS

Prospective study in a tertiary neonatal intensive care unit. Inclusion criteria were term neonates with respiratory distress requiring noninvasive respiratory support with nasal continuous positive airway pressure (nCPAP) within first 6 h of life with an LUS score higher than 8 were enrolled. LUS was performed three times. First LUS (LUS-1) was done in patients in nCPAP (Fabian Device) (Acutronic) (pressure of 6 cmH₂ O). Afterwards patients were placed in duo positive airway pressure (12/6 cmH₂ O), a second LUS (LUS-2) was performed immediately and a third (LUS-3) was done 2 h later on the same respiratory support. The primary outcome was to compare LUS scores in the different timelines. Second outcomes were to evaluate the level of respiratory distress and oxygenation were evaluated with SpO₂ /fraction of inspired oxygen (FiO₂ ) ratio (S/F ratio), FiO₂  ratio, respiratory rate, and blood gas analysis which were analyzed during the LUS-1 and the LUS-3. To evaluate newborn discomfort, patients were evaluated with Crying Requires oxygen Increased vital signs Expression Sleep (CRIES) scale.

RESULTS

Forty neonates were enrolled. Fifty percent were female (n = 20), median gestational age was 38 + 4 (interquartile range [IQR]: 37 + 5-39 + 4) with a median weight of 3155 g (IQR: 2637-3532). Duration of non invasive ventilation support was 72 h (IQR: 54-96). None of the patients required surfactant therapy or mechanical ventilation. LUS scores were no different between LUS-1 9 (IQR: 8.3-10) and LUS-2 9 (IQR: 8.3-10) (p = 0.675) but there were differences between LUS-1 and LUS-3 7 (IQR: 6.3-8.5) (p = 0.036). There was an improvement in the oxygen parameters, respiratory rate, and CO₂ between LUS-1 and LUS-3 (p < 0.001). There were no changes in the CRIES scale.

CONCLUSIONS

There is an improvement in clinical and laboratory parameters after the increasing of respiratory support in newborns with noninvasive ventilation. We observe a correlation with an improvement in the assessment of lung aeration were evaluated with LUS score.

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.

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.

Prediction of weaning readiness off nasal CPAP in preterm infants using point-of-care lung ultrasound

This study's primary aim was to assess whether end-expiratory lung ultrasound severity score (expLUSsc) at Day 3 of life, the second week of life, and before weaning off nasal continuous positive airway pressure (nCPAP) can predict the weaning readiness off nCPAP trial in preterm infants. The secondary aim was to evaluate the value of adding lung tidal recruitment (LTR) to expLUSsc (expLUSsc-plus-LTR) to improve predictability. We conducted a prospective study on premature infants <33 weeks of gestation. Point-of-care lung ultrasound (POC-LUS) was performed on Day 3, the second week of life, before and after the trial off nCPAP. expLUSsc, pleural thickness, and LTR were assessed. A receiver operator curve was constructed to evaluate the ability of POC-LUS to predict the weaning readiness off nCPAP. A total of 148 studies were performed on 39 infants, of them 12 weaned off nCPAP from the first trial and 27 infants failed attempts off nCPAP. An expLUSsc cut-off 8 before the first trial of weaning off nCPAP has a sensitivity and specificity of 88% and 90%, and positive and negative predictive values of 87% and 92%, respectively, with area under the curve (AUC) was 0.87 (CI: 0.8-0.93), p < .0001. If LTR is added to an expLUSsc cut-off 8 (expLUSsc-plus-LTR) before the first trial of weaning, then sensitivity and specificity of 95% and 90%, and positive and negative predictive values of 88% and 90%, respectively, with AUC was 0.95 (CI: 0.91-0.99), p < .0001. In conclusion, this study demonstrated the ability of POC-LUS to predict the weaning readiness off nCPAP in premature infants. The use of this simple bedside noninvasive test can potentially avoid the exposure of premature infants to multiple unsuccessful weaning cycles.

Early lung ultrasound score to predict noninvasive ventilation needing in neonates from 33 weeks of gestational age: A multicentric study

OBJECTIVE

To propose an early lung ultrasound (LUS) score for the prediction of the need for respiratory assistance in newborns of gestational age (GA) ≥ 33 weeks presenting respiratory distress.

STUDY DESIGN AND SETTING

Multicenter, prospective observational study in third-level neonatal intensive care units.

PATIENT SELECTION

Infants with GA ≥ 33 + 0 weeks with respiratory distress within 3 h of life.

METHODS

Three LUS for each patient were collected: within 3 h of life (T0), at 4-6 h of life (T1), and at the resolution of symptoms (T2). The primary aim was to assess the validity of the early LUS score in predicting the need for continuous positive airway pressure (CPAP). We also evaluated the validity of the score in predicting the need for surfactant, the scores' trend in our population, and any correlation with the duration of ventilation and oxygen therapy.

RESULTS

Sixty-two patients were enrolled in the study. The mean GA was 36 weeks. The receiver operating characteristic analysis for the LUS T0 and T1 yielded area under the curves of 0.91 and 0.82 in predicting the need for CPAP, respectively. LUS score cut off of 6 (sensitivity 84.8%, specificity 86.2%) and 5 (sensitivity 66.7%, specificity 100%) were calculated at T0 and T1, respectively. We found significant correlations between LUS score and respiratory assistance, surfactant administration, and SpO₂ /FiO₂ ratio.

CONCLUSION

An early LUS score is a good noninvasive predictor of the need for respiratory assistance with CPAP and surfactant administration in newborns with GA ≥ 33 weeks.

Semi-quantitative lung ultrasound score during ground transportation of outborn neonates with respiratory failure

Lung ultrasound score (LUS) is increasingly diffused in neonatal critical care but scanty data are available about its use during transfer of severely ill neonates. We aimed to clarify the effect of ground transportation on LUS evolution, conformity of interpretation, and relationships with oxygenation and clinical severity. This is a single-center, blinded, observational, cross-sectional study. Neonates of any gestational age with respiratory distress appearing within 24 h from birth were transferred by a mobile unit towards neonatal intensive care unit (NICU) of a tertiary referral center. Calculation of LUS prior to the transportation (T1), in the mobile unit (T2), at the end of transportation (T3), and finally upon NICU admission. LUS in the mobile unit and in the NICU was performed by different physicians blinded to each other's results. LUS did not change overtime (T1: 6.3 (3.5), T2: 6.1 (3.5), T3: 5.8 (3.4); p = 0.479; adjusted for gestational or postnatal age or transport duration: p = 0.951, p = 0.424, and 0.266, respectively) but reliably predicted surfactant need (AUC at T1: 0.833 (95%CI: 0.72-0.92); AUC at T2: 0.82 (95%CI: 0.70-0.91); AUC at T3: 0.82 (95%CI: 0.70-0.90); p always < 0.0001). There were significant agreement (ICC = 0.912 (95%CI: 0.83-0.95); p < 0.001) and correlation (r = 0.905, p < 0.001) between LUS calculated during transportation and in the NICU. LUS during transportation was also significantly correlated with oxygenation index (r = 0.321, p = 0.026; standardized B = 0.397 (95%CI: 0.03-0.76), p = 0.048) and TRIPS-II score (r = 0.302, p = 0.008; standardized B = 0.568 (95%CI: 0.04-1.1), p = 0.037).

CONCLUSION

LUS during ground transportation of neonates with respiratory failure is suitable and not influenced by the transportation itself. It has a high agreement with that calculated in the NICU and correlates with patients' oxygenation and severity.

WHAT IS KNOWN

• Lung ultrasound is a part of the point-of-care ultrasound, which is becoming an essential tool, to manage critically ill neonates and children in an accurate, non-invasive and quick way.

WHAT IS NEW

• Lung ultrasound score (LUS) is suitable during transportation of critically ill neonates with respiratory failure and is not influenced by the transportation itself. • LUS has a high agreement with that calculated in the NICU and correlates with patients' oxygenation and severity of respiratory failure.

Lung ultrasound score has better diagnostic ability than NT-proBNP to predict moderate-severe bronchopulmonary dysplasia

The N-terminal end of B-type natriuretic peptide (NT-proBNP) and lung ultrasound (LUS) score have been proven to be adequate early biomarkers of bronchopulmonary dysplasia (BPD) in preterm infants. Our aim was to study if the predictive capacity of each one is increased by analyzing them together. We included infants born before 32 weeks with NT-proBNP and LUS scores on the first day of life (DOL) and on the 3rd, 7th, and 14th DOL and compared the diagnostic ability for moderate-severe BPD (msBPD) of each biomarker and in combination. We also compared them with a multivariate model of msBPD using only clinical variables. The sample size was 133 patients, and twenty-seven (20%) developed msBPD. The LUS score on the 7th DOL had better performance than NT-proBNP at the same moment: area under the receiver operating characteristic curve (AUC) 0.83 (0.75-0.89) versus 0.66 (0.56-0.75), p = 0.003, without differences in the rest of the times studied. These values did not increase when using the combination of both. A multivariate regression model that included only clinical variables (birth weight and invasive mechanical ventilation (IMV) at the 7th DOL) predicted msBPD with the same AUC as after the addition of any of these biomarkers, neither together.

CONCLUSION

The LUS score is a better predictor of msBPD on the 7th DOL than NT-proBNP in preterm infants born before 32 weeks, although they have similar diagnostic accuracy on the 1st, 3rd, and 14th DOL. Neither of them, nor together, have a better AUC for msBPD than a clinical model with birthweight and the need for IMV at the 7th DOL.

WHAT IS KNOWN

• NT-proBNP and LUS score are early predictors of moderate-severe bronchopulmonary dysplasia (msBPD).

WHAT IS NEW

• The combination of both NT-proBNP and LUS score does not increase the predictive ability of each separately.

Prognostic Role of Lung Ultrasound in Children with Bronchiolitis: Multicentric Prospective Study

There is increasing recognition of the role of lung ultrasound (LUS) to assess bronchiolitis severity in children. However, available studies are limited to small, single-center cohorts. We aimed to assess a qualitative and quantitative LUS protocol to evaluate the course of bronchiolitis at diagnosis and during follow-up. This is a prospective, multicenter study. Children with bronchiolitis were stratified according to clinical severity and underwent four LUS evaluations at set intervals. LUS was classified according to four models: (1) positive/negative; (2) main LUS pattern (normal/interstitial/consolidative/mixed) (3) LUS score; (4) LUS score with cutoff. Two hundred and thirty-three children were enrolled. The baseline LUS was significantly associated with bronchiolitis severity, using both the qualitative (positive/negative LUS p < 0.001; consolidated/normal LUS pattern or mixed/normal LUS p < 0.001) and quantitative models (cutoff score > 9 p < 0.001; LUS mean score p < 0.001). During follow-up, all LUS results according to all LUS models improved (p < 0.001). Better cut off value was declared at a value of >9 points. Conclusions: Our study supports the role of a comprehensive qualitative and quantitative LUS protocol for the identification of severe cases of bronchiolitis and provides data on the evolution of lung aeration during follow-up.

Lung Ultrasound Scores Progress Differently in Extreme and Very Preterm Infants after Birth: A Multicentre Prospective Study

INTRODUCTION

The lung ultrasound score (LUS) has been suggested to predict moderate-severe bronchopulmonary dysplasia (msBPD) in preterm infants. We aimed to assess LUS evolution after birth in preterm infants and the effect of gestational age.

METHODS

This multicentre prospective observational study was performed with newborns born before 33 weeks of gestation. We created two groups: group 1 (23-27 weeks) and group 2 (28-32 weeks). We compared LUSs between the groups from birth until 36 weeks of postmenstrual age, and we estimated the LUS evolution in each group with a linear multilevel mixed-effects regression model. The effects of the need for surfactant or an msBPD diagnosis were also studied.

RESULTS

We included 339 patients: 122 (36%) in group 1 and 217 (64%) in group 2. The infants in group 1 showed a steady progression in the LUS from birth until 4 weeks of age and a subsequent decrease; the infants in group 2 showed a progressive decrease in the LUS throughout the study. This progression varied significantly in the first weeks of life in infants who required surfactant at birth and after the first week of life in the patients diagnosed with msBPD.

DISCUSSION/CONCLUSIONS

Extremely preterm infants showed persistently high LUSs during the first weeks of life, regardless of the progression to msBPD. In this group, the infants who did not require surfactant at birth exhibited an increase in their LUSs after the first week until their values were equal to the remaining infants in their group.

Diagnostic accuracy of lung ultrasound for transient tachypnea: a meta-analysis

OBJECTIVE

The objective of this meta-analysis was to study the diagnostic value of lung ultrasound (LUS) for transient tachypnea of the newborn (TTN).

METHODS

Embase, Cochrane Library, PubMed, Web of Science, and Google Scholar were searched, and the last search date was October 31, 2020. Studies on the diagnostic accuracy of pulmonary ultrasound for transient tachypnea were included. The quality assessment of the included study was assessed using the Diagnostic Accuracy Studies-2 tool. A meta-analysis was performed using Meta-Disc 1.4. A random-effects model was used and subgroup analysis was carried out to identify possible sources of heterogeneity.

RESULTS

A total of 378 articles were retrieved and nine studies with 3239 patients were included in the present meta-analysis. The overall quality of the included studies was moderate to high. The result of threshold analysis shows that there was no threshold effect. However, there was a significant heterogeneity caused by non-threshold effects in the included studies. A random-effects model was used. The pooled sensitivity, specificity, PLR and NLR were 0.55 (95% CI: 0.51-0.58), 0.98 (95% CI: 0.98-0.99), 58.30 (95% CI: 14.05-241.88) and 0.28 (95% CI: 0.18-0.43). The pooled DOR and AUC were 689.12 (95% CI: 68.71 to 6911.79) and 0.994. The results of subgroup analysis showed that the LUS diagnostic criteria and gold standard might be responsible for heterogeneity. Choosing "DLP combined with B line" as the diagnostic standard of LUS and choosing CXR as the gold standard could significantly improve the diagnostic performance of LUS.

CONCLUSION

LUS is a promising method to diagnose TTN. Only DLP is not enough to diagnose TTN, while DLP combined with B-line has good diagnostic performance.

The Assessment of COVID-19 Pneumonia in Neonates: Observed by Lung Ultrasound Technique and Correlated with Biomarkers and Symptoms

Newborns infected with SARS-CoV2 infection develop different symptoms in comparison with adults, but one thing is clear: some of the most common manifestations include cough and other respiratory symptoms that need to be evaluated. In these cases, lung ultrasound is a useful imaging technique that can evaluate the newborns’ lung damage caused by COVID-19 pneumonia and can be used for the surveillance of the patients as well, being non-irradiating and easy to use. Nineteen neonates who were confirmed as having SARS-CoV2 infection were investigated using this imaging tool, and the results were compared and correlated with their symptoms and biomarkers. The mean of LUSS was 12.21 ± 3.56 (S.D), while the 95% CI for the arithmetic mean was 10.49–13.93. The difference of an independent t-test between the LUSS for the patient who presented cough and the LUSS for the patient without cough was −4.48 with an associated p-value of p = 0.02. The Pearson’s correlation coefficient r = 0.89 (p = 0.03, 95% CI 0.0642 to 0.993) between the LUSS and IL-6 level showed a positive strong correlation. This reliable correlation between lung ultrasound score and inflammatory markers suggests that LUS could be used for monitoring inflammatory lung diseases in the future.

Lung ultrasound score parallels trends in systemic haemodynamics after PDA ligation: a case series

B-lines in lung ultrasound (LU) are non-specific but highly informative sign of interstitial pulmonary oedema (iPE). Sustained exposure to a high-volume left-to-right patent ductus arteriosus (PDA) shunt is associated with iPE. Cardiorespiratory deterioration, named post-ligation cardiac syndrome (PLCS), may follow surgical ligation between 6 and 12 h post-operatively. We conducted a pilot longitudinal evaluation of peri-procedural LU score change. Infants < 32-week gestational age or < 1500-g birthweight undergoing PDA ligation, where pre-, 1 h and 6-12 h LU were performed, were included. Two independent raters evaluated LU score (LUS). Neonatologist performed echocardiography (NPE) was performed concurrently to appraise changes in left ventricular output (LVO). Milrinone was initiated if LVO was < 200 mL/kg/min 1 h after surgery, to prevent PLCS. The primary outcome was peri-procedural LUS change. Secondary outcomes included PLCS. Five infants were included (birthweight 787(88) g; gestational age 25.6(0.7) weeks). Postnatal age and weight at the intervention were 41(14) days and 1175(295) g. All infants, but one, received milrinone prophylaxis. None of the patients developed PLCS or required rescue HFOV. Post-interventional LUS were lower compared to pre-operative LUS (p = 0.041 vs 1 h, p = 0.042 vs 6-12 h). A concurrent fall post-operative LVO was noted (p < 0.05 vs pre-operative).

CONCLUSION

A sustained fall in LUS after PDA ligation was identified, which most likely reflects reduction in pulmonary blood flow and interstitial edema. Changes in LUS paralleled changes in LVO, suggesting physiologic linkage. These data suggest that LU may be a useful tool to guide monitoring the biologic nature of pulmonary disease after PDA ligation.

WHAT IS KNOWN

• Sustained exposure to a high-volume left-to-right patent ductus arteriosus (PDA) shunt is associated with interstitial pulmonary oedema. • In the most immature patients, cardiorespiratory deterioration, named post-ligation cardiac syndrome, presents 6-12 h post-operatively.

WHAT IS NEW

• An early and sustained fall in lung ultrasound score (LUS) after PDA ligation most likely reflects reduction in pulmonary blood flow and interstitial oedema. LUS changes parallel changes in left ventricular output, suggesting linkage. • LU is a promising adjunctive tool in the post-operative management of PDA ligation.

Lung ultrasound scores in neonatal clinical practice: A narrative review of the literature

Lung ultrasound (LU) has in recent years increasingly been used as a point-of-care method. Initially, LU was used as a so-called descriptive diagnostic method for neonatal respiratory diseases. Instead, this review article focuses on the use of LU as a "functional" tool using classification of findings in patterns or using semiquantitative scores. We review and describe the evidence that led to the implementation of LU in predicting the need for surfactant replacement therapy in preterm infants and in the identification of newborns at risk of developing bronchopulmonary dysplasia. LU appears to be a very promising method for the future of clinical management of newborns in both acute and chronic phases of pulmonary pathologies related to prematurity. However, further studies are needed to define its role before full implementation.

Pharmaceutical Expenditure Is Unchanged with Ultrasound-Guided Surfactant Administration

OBJECTIVE

Semiquantitative lung ultrasound improves the timeliness of surfactant replacement, but its financial consequences are unknown. We aim to investigate if the ultrasound-guided surfactant administration influences the general costs of surfactant therapy for preterm neonates affected by respiratory distress syndrome.

STUDY DESIGN

This is a pharmacoeconomic, retrospective, and before-and-after study investigating the impact of ultrasound-guided surfactant replacement (echography-guided Surfactant THERapy [ESTHER]) on pharmaceutical expenditure within the ESTHER initiative. Data extracted from the institutional official database hosted by the hospital administration for financial management were used for the analysis. We analyzed the number of surfactant administrations in neonates of gestational age ≤32^6/7 weeks, and the number of surfactant vials used from January 1_, 2014 to June 30, 2014 (i.e., during the period of standard surfactant administration policy) and from July 1, 2016 to December 31, 2018 (that is during ESTHER policy).

RESULTS

ESTHER did not modify surfactant use, as proportion of treated neonates with RDS receiving at least one surfactant dose (Standard: 21.3% vs. ESTHER: 20.9%; p = 0.876) or as proportion of used vials over the total number of vials opened for neonates of any gestational age (Standard: 37% vs. ESTHER: 35%; p = 0.509).

CONCLUSION

Ultrasound-guided surfactant replacement using a semiquantitative lung ultrasound score in preterm infants with RDS does not change the global use of surfactant and the related expenditure.

KEY POINTS

· ESTHER is able to increase the timeliness of surfactant replacement.. · The ultrasound-guided surfactant administration does not increase the cost of surfactant therapy.. · The ultrasound-guided surfactant administration does not change the global surfactant utilization..

Neonatal pneumothoraces with atypical location: the role of lung ultrasound

Neonatal pneumothorax (NP) is a potentially life-threatening condition. Lung ultrasound (LUS) has shown higher sensitivity and specificity in diagnosis compared to x-rays, but evidence regarding its usefulness in complex NP is lacking. We report four neonates suffering from cardiac or esophageal malformations who developed lateral and/or posterior pneumothoraces, in which LUS helped, making NP diagnosis and management easier and faster.

CONCLUSION

LUS is an easy-to-use, fast, simple, and accurate tool when evaluating newborns with NP, also in atypical positions such as in surgical patients.

WHAT IS KNOWN

• Lung ultrasound (LUS) has higher sensitivity and specificity than x-rays in the diagnosis of pneumothorax in neonatal patients.

WHAT IS NEW

• This is the first report about neonatal pneumothorax in non-conventional areas (lateral/posterior) diagnosed by lung ultrasound and how obtaining this information is critical in order to optimize management.

Ultrasound of pneumothorax in neonates: Diagnostic value of the anterior transverse plane and of mirrored ribs

INTRODUCTION

Point-of-care lung ultrasound is increasingly used to diagnose pneumothorax efficiently and safely in neonates.

OBJECTIVES

This study aimed to evaluate the usefulness of the central and anterior transverse thoracic plane in the ultrasound diagnosis of pneumothorax, analyze the diagnostic value of the "mirrored ribs" sign, and evaluate the predictive value of the lung point location for the need of pleural drainage.

METHODS

Retrospective cohort study of all newborns admitted to the neonatal intensive care unit of the Basurto University Hospital (Bilbao, Spain) due to respiratory distress and with ultrasound, with or without pneumothorax, between January 2014 and December 2020.

RESULTS

The presence of A-lines behind the sternum in the anterior transverse plane in newborns with pneumothorax (N = 311) and controls (N = 195) was compared. A-lines were present in 98.9% of newborns with pneumothorax compared to none in the controls (p < .0001). Diagnosis of pneumothorax with the anterior transverse plane presented high interobserver reproducibility (κ = 0.92, 95% confidence interval: 0.84-1.00). In contrast, the "mirrored ribs" sign in the anterior longitudinal plane was observed in 35.6% of patients with pneumothorax and in 36.9% of controls (p = .1505). A significant association was observed between lung point location and the need for pleural drainage (p < .0001).

CONCLUSIONS

A-lines in the anterior transverse plane is a simple ultrasound sign which presents high sensitivity, specificity, and reproducibility for the diagnosis of pneumothorax. The mirrored ribs sign showed low diagnostic utility. Patients with severe pneumothorax in lung ultrasound are most likely to require thoracic drainage.

Pleuro-pulmonary ultrasound in the diagnosis and follow-up of lung infections in children with cancer: a pilot study

PURPOSE

Febrile neutropenia and lung infections are common and potential fatal complications of pediatric cancer patients during chemotherapy. Lung ultrasound (LUS) has a good accuracy in the diagnosis of pneumonia in childhood, but there is no data concerning its use in the diagnosis and follow-up of pulmonary infection in children with cancer. The goal of this pilot study is to verify the feasibility of lung ultrasonography for the diagnosis and follow up of pneumonia in children and adolescents with cancer.

MATERIAL AND METHODS

This is a prospective observational case-control monocentric study conducted in the Pediatric Hematology and Oncology Department of University Hospital of Catania in patients aged < 18 years with cancer. Attending Physician used ultrasonography to detect pneumonia in cancer children with fever. As control group, cancer patients with no infection suspicion were also tested. LUS results were compared to chest X-ray (CXR) and/or chest CT scan, when these imaging techniques were performed, according to clinical indication.

RESULTS

Thirty-eight patients were studied. All underwent LUS, 16 underwent CXR, 3 chest CT. Statistical analysis showed LUS specificity of 93% (95% CI 84-100%), and sensitivity of 100%; CXR, instead, showed a specificity of 83% (95% CI 62-100%) and a sensitivity of 50% (95% CI 1-99%).

CONCLUSION

This study shows for the first time that LUS allows physicians to diagnose pneumonia in children and young adults with cancer, with high specificity and sensitivity.

Lung ultrasonography decreases radiation exposure in newborns with respiratory distress: a retrospective cohort study

Chest X-ray (CXR) is commonly used as a first-line imaging method to determine the cause of respiratory distress in NICUs. The aim of the study was to retrospectively assess the decrease in the number of CXRs performed due to the use of lung ultrasonography on the first day of life for newborns with respiratory distress. Infants who were admitted to the NICU on the first day of life due to respiratory distress were enrolled in this study (ClinicalTrials.gov identifier NCT04722016) and divided into two groups: the study group (n = 104) included patients born between January 2019 and June 2020, and the historical control group (n = 73) included patients born between June 2017 and December 2018. As a first-line technique for lung imaging, only CXR had been used in the historical control group, whereas ultrasound had been preferred in the study group. The radiation dose to the newborns and the number of CXRs performed in the first day of life were compared between the two groups. Significant reductions in the number of CXRs performed and radiation exposure were observed in the study group. The radiation dose decreased from 5.54 to 4.47 µGy per baby when LUS was routinely used. The proportion of patients who underwent CXR decreased from 100 to 71.2%.Conclusion: We observed that using lung ultrasonography as a first-line evaluation method in neonates with respiratory distress decreased both the number of CXRs performed and radiation exposure. What is Known: • Chest X-ray is commonly used as a first line imaging method to diagnose the reason of respiratory distress in NICUs. • Lung ultrasound is a new diagnostic tool for lung imaging. What is New: • With the use of lung ultrasonography, radiation exposure of both newborns and healthcare workers can be reduced. • This retrospective study revealed that most of the babies with respiratory distress were treated without CXR.

Chest ultrasound in neonates: What neonatologists should know

For many years, ultrasound was thought to have no indications in pulmonary imaging because lungs are filled with air, creating no acoustic mismatch, as encountered by ultrasound wave beam. Lung ultrasound (LUS) was started in adult critical care settings to detect pleural effusion and acquired more indications over time. In the neonatal intensive care unit (NICU), the use of chest ultrasound has gained more attention during the last two decades. Being a radiation-free, bedside, rapid, and handy tool, LUS started to replace chest X-rays in NICU. Using LUS depends upon understanding the nature of normal lungs and the changes induced by different diseases. With the help of LUS, an experienced neonatologist can detect many of the respiratory problems so fast that interventional therapy can be introduced as early as possible. LUS can diagnose pleural effusion, pneumothorax, pneumonia, transient tachypnoea of the newborn, respiratory distress syndrome, pulmonary atelectasis, meconium aspiration syndrome, bronchopulmonary dysplasia, and some other disorders with very high accuracy. LUS will be helpful in initial diagnosis, follow-up, and predicting the need for further procedures such as mechanical ventilation, diuretic therapy, surfactant therapy, etc. There are some limitations to using LUS in some respiratory disorders such as bullae, interstitial emphysema, and other conditions. This review will highlight the importance of LUS, its uses, and limitations.

Ten Years of Pediatric Lung Ultrasound: A Narrative Review

Lung diseases are the most common conditions in newborns, infants, and children and are also the primary cause of death in children younger than 5 years old. Traditionally, the lung was not thought to be a target for an ultrasound due to its inability to penetrate the gas-filled anatomical structures. With the deepening of knowledge on ultrasound in recent years, it is now known that the affected lung produces ultrasound artifacts resulting from the abnormal tissue/gas/tissue interface when ultrasound sound waves penetrate lung tissue. Over the years, the application of lung ultrasound (LUS) has changed and its main indications in the pediatric population have expanded. This review analyzed the studies on lung ultrasound in pediatrics, published from 2010 to 2020, with the aim of highlighting the usefulness of LUS in pediatrics. It also described the normal and abnormal appearances of the pediatric lung on ultrasound as well as the benefits, limitations, and possible future challenges of this modality.

Lung Ultrasound for the Diagnosis and Management of Neonatal Respiratory Distress Syndrome: A Minireview

Lung ultrasound (LUS) is useful for diagnosis of respiratory distress syndrome in neonates. Recently, it has been proved to play an important role in the management of neonatal respiratory distress syndrome (RDS). It is feasible to grade RDS and select therapeutic modalities accordingly by LUS. The treatment also should be adjusted with the change in ultrasound images. In conclusion, LUS is valuable for the diagnosis and management of neonatal respiratory distress syndrome.

Targeted management of evolving and established chronic lung disease of prematurity assisted by cardiopulmonary ultrasound: A case report of four patients

Bronchopulmonary dysplasia (BPD) is one of the most common complications of premature birth. The current definition of BPD is based on the duration of oxygen therapy and/or respiratory support. Among the pitfalls of all the diagnostic definitions, the lack of a proper pathophysiologic classification makes it difficult to choose an appropriate drug strategy for BPD. In this case report, we describe the clinical course of four premature infants, admitted to the neonatal intensive care unit, for whom the use of lung and cardiac ultrasound was an integral part of the diagnostic and therapeutic process. We describe, for the first time to our knowledge, four different cardiopulmonary ultrasound patterns of evolving and established chronic lung disease of prematurity and the consequent therapeutic choices. This approach, if confirmed in prospective studies, may guide the personalized management of infants suffering from evolving and established BPD, optimizing the chances of success of the therapies and at the same time reducing the risk of exposure to inadequate and potentially harmful drugs.

"Playing it SAFE in the NICU" SAFE-R: a targeted diagnostic ultrasound protocol for the suddenly decompensating infant in the NICU

Rapid diagnosis of sudden, unexpected, and potentially fatal complications in the neonatal intensive care unit (NICU) is essential for the initiation of prompt and life-saving management. Point-of-care ultrasound (POCUS) protocols are widely used in adult emergency situations to diagnose and guide treatment, but none has been specifically developed for the neonate. We propose a targeted diagnostic ultrasound protocol for the suddenly decompensating infant in the NICU for rapid screening for the most common life-threatening complications needing immediate attention. We integrated current knowledge on the use of POCUS for diagnosis of the most critical neonatal complications into the "SAFE-R protocol" (Sonographic Assessment of liFe-threatening Emergencies - Revised). The ultrasound algorithm was evaluated at the bedside for suitability and ease of use. Main features of SAFE-R are the use of standardized ultrasound points and a simple one-probe rule-in/rule-out approach. The flowchart is designed by order of urgency and priority is given to treatable causes. Hence, ruling out cardiac tamponade is the first step in the decision tree, followed by pneumothorax, pleural effusion, then acute critical aortic occlusion, acute abdominal complications, and severe intraventricular hemorrhage.Conclusion: SAFE-R is the first ultrasound algorithm specifically conceived for use in the NICU to screen for the most common urgent neonatal complications leading to sudden deterioration, thereby providing critical information within minutes. The simplified and rapid approach is designed for the neonatologist and is easy to learn and quick to perform. What is Known: • The fields of neonatal and pediatric critical care are undergoing a transformation with the adoption of POCUS and the recent publication of the first international guidelines on POCUS for critically ill children and neonates. • Targeted emergency ultrasound protocols are widely used in adult emergency and critical care medicine, but specific and adapted ultrasound algorithms are lacking for the pediatric and neonatal population. What is New: • We propose the first targeted ultrasound protocol specifically designed for the suddenly decompensating infant in the NICU for rapid screening of the most common life-threatening complications needing immediate attention. • The SAFE-R ultrasound algorithm integrates current knowledge on ultrasound diagnosis of the most critical neonatal complications into a simple and easy-to-perform emergency scanning protocol aimed to guide initial management and resuscitation efforts.

Lung Ultrasound Characteristics in Neonates With Positive Real Time Polymerase Chain Reaction for SARS-CoV-2 on a Tertiary Level Referral Hospital in Mexico City

INTRODUCTION

Acute respiratory syndrome secondary to SARS-CoV-2 virus infection has been declared a pandemic since December 2019. On neonates, severe presentations are infrequent but possible. Lung ultrasound (LUS) has been shown to be useful in diagnosing lung involvement and following up patients, giving more information, and reducing exposure compared to traditional examination.

METHODS

LUS was performed after the diagnosis of SARS-CoV-2 infection with respiratory Real Time Polymerase Chain Reaction RT-PCR with portable equipment protected with a silicone sleeve. If hemodynamic or cardiology consultation was necessary, a prepared complete ultrasound machine was used. Ten regions were explored (anterior superior and inferior, lateral, and posterior superior and inferior, right and left), and a semiquantitative score (LUSS) was calculated. Disease severity was determined with a pediatric modified score.

RESULTS

Thirty-eight patients with positive RT-PCR were admitted, 32 (81%) of which underwent LUS. Included patients had heterogenous diagnosis and gestational ages as expected on a referral neonatal intensive care unit (NICU) (median, ICR: 36, 30-38). LUS abnormalities found were B-line interstitial pattern 90%, irregular/interrupted/thick pleural line 88%, compact B-lines 65%, small consolidations (≤5 mm) 34%, and extensive consolidations (≥5 mm) 37%. Consolidations showed posterior predominance (70%). LUSS showed a median difference between levels of disease severity and ventilatory support (Kruskal-Wallis, p = 0.001) and decreased with patient improvement (Wilcoxon signed-rank test p = 0.005). There was a positive correlation between LUSS and FiO₂ needed (Spearman r = 0.72, p = 0.01). The most common recommendation to the attending team was pronation (41%) and increase in positive end expiratory pressure (34%). Five patients with comorbidities died. A significant rank difference of LUSS and FiO₂ needed between survivors and non-survivors was found (Mann-Whitney U-test, p = 0.005).

CONCLUSION

LUS patterns found were like the ones described in other series (neonatal and pediatrics). Eighty-eight percent of the studies were performed with handheld affordable equipment. While there is no specific pattern, it varies according to gestational age and baseline diagnosis LUS, which were shown to be useful in assessing lung involvement that correlated with the degree of disease severity and respiratory support.

Application of ultrasonography in neonatal lung disease: An updated review

Lung disease is often life-threatening for both preterm and term newborns. Therefore, an accurate and rapid diagnosis of lung diseases in newborns is crucial, as management strategies differ with different etiologies. To reduce the risk of radiation exposure derived from the conventionally used chest x-ray as well as computed tomography scans, lung ultrasonography (LUS) has been introduced in clinical practice to identify and differentiate neonatal lung diseases because of its radiation-free characteristic, convenience, high accuracy, and low cost. In recent years, it has been proved that LUS exhibits high sensitivity and specificity for identifying various neonatal lung diseases. Here, we offer an updated review of the applications of LUS in neonatal lung diseases based on the reports published in recent years (2017 to present).

Is Lung Ultrasound Helpful in COVID-19 Neonates?-A Systematic Review

Background: The SARS-CoV-2 infection has occurred in neonates, but it is a fact that radiation exposure is not recommended given their age. The aim of this review is to assess the evidence on the utility of lung ultrasound (LUS) in neonates diagnosed with COVID-19. Methods: A systematic literature review was performed so as to find a number of published studies assessing the benefits of lung ultrasound for newborns diagnosed with COVID and, in the end, to make a comparison between LUS and the other two more conventional procedures of chest X-rays or CT exam. The key terms used in the search of several databases were: “lung ultrasound”, “sonography”, “newborn”, “neonate”, and “COVID-19′. Results: In total, 447 studies were eligible for this review, and after removing the duplicates, 123 studies referring to LU were further examined, but only 7 included cases of neonates. These studies were considered for the present research paper. Conclusions: As a non-invasive, easy-to-use, and reliable method for lung lesion detection in neonates with COVID-19, lung ultrasound can be used as a useful diagnosis tool for the evaluation of COVID-19-associated lung lesions. The benefits of this method in this pandemic period are likely to arouse interest in opening new research horizons, with immediate practical applicability.

Lung Ultrasound in the Neonatal Intensive Care Unit: Does It Impact Clinical Care?

A neonatal point-of-care ultrasound has multiple applications, but its use has been limited in neonatal intensive care units in the Unites States. An increasing body of evidence suggests that lung ultrasound performed by the neonatologist, at the bedside, is reliable and accurate in differentiating neonatal respiratory conditions, predicting morbidity, and guiding invasive interventions. Recent research has shown that a lung ultrasound can assist the clinician in accurately identifying and managing conditions such as respiratory distress syndrome, transient tachypnea of the newborn, and bronchopulmonary dysplasia. In this review, we discuss basic lung ultrasound terminology, evidence for applications of neonatal lung ultrasound, and its use as a diagnostic and predictive tool for common neonatal respiratory pathologies.

Meta-analysis of Lung Ultrasound Scores for Early Prediction of Bronchopulmonary Dysplasia

RATIONALE

Lung ultrasound scores (LUS) might be useful in monitoring neonates with chronic pulmonary insufficiency of prematurity and in predicting bronchopulmonary dysplasia (BPD). Given their ease of use, accuracy and lack of invasiveness, LUS have been the subject of several recent studies.

OBJECTIVE

We sought to clarify whether LUS provide an accurate and early (within the first two weeks of life) prediction of BPD in preterm infants of gestational age <32weeks.

METHODS

Systematic review and diagnostic accuracy meta-analysis following PRISMA-P, PRISMA and QUADAS guidelines. Studies designed to predict BPD in the first two weeks of life using LUS were selected. A classical LUS (calculated for 6 chest areas) and its extended version (eLUS, 10 chest areas) were tested.

RESULTS

Seven studies (1027 neonates) were meta-analyzed. LUS and eLUS showed good diagnostic accuracy in predicting BPD at 7 and 14 days of life (AUC 0.85-0.87, pooled sensitivity 70-80%, pooled specificity 80-87%). The diagnostic accuracy of LUS and eLUS did not differ at any timepoint (AUC difference always p >0.05). Repeating the analyses without outliers or with moderate-to-severe BPD as outcome yielded similar results. Meta-regressions showed that prenatal steroid prophylaxis and sex were not significant effect confounders.

CONCLUSIONS

LUS are accurate for early prediction of BPD and moderate-to-severe BPD, in an average population of preterm infants <32weeks' gestation. The diagnostic accuracy is similar for LUS and eLUS, so the use of the simpler score should be advocated. Registration. PROSPERO CRD42021233010.

Lung ultrasound predicts the development of bronchopulmonary dysplasia: a prospective observational diagnostic accuracy study

This study aimed to evaluate the predictive ability of lung ultrasound (LU) in the development of bronchopulmonary dysplasia (BPD) in very low birth weight (VLBW) infants. A total of 130 VLBW infants with gestational age < 32 weeks were included; LU was performed at days 1, 2, 3, 6, 9, 12, and 15 postnatally. We calculated the LU score by 12-region, 10-region, and 6-region protocols. The incidence of BPD according to the National Institutes of Health (NIH) 2001 definition and 2019 criteria was 38.5% and 64.6%, respectively. By 12-region and 10-region protocols, LU predicted BPD from the 9^th to 15^th days of life (DOLs) regardless of the criteria used, with an area under the curve (AUC) ranging from 0.826 (95% confidence interval (CI): 0.750-0.887) to 0.877 (95% CI: 0.807-0.928). According to the 2019 BPD definition, the LU score incorporated gestational age, and invasive mechanical ventilation >6 days predicted BPD on the 6^th DOL with an AUC of 0.862 (95% CI: 0.790-0.916). The 6-region protocol had significantly smaller AUC values on the 6^th and 9^th DOLs than the other two protocols.Conclusion: The 12-region and 10-region LU scoring protocols are superior to the 6-region protocol in the prediction of BPD. LU can predict the development of BPD from the 9^th to 15^th DOLs. With the addition of clinical variables, the earliest prediction time was the 6^th DOL. What is Known: • Bronchopulmonary dysplasia is the most common and adverse complication of prematurity. Recent four studies found that lung ultrasound score or findings predicted the development of bronchopulmonary dysplasia. What is New: • We present analysis by classical 6-region and the other two lung ultrasound score (10-region and 12-region) which include an assessment of the posterior lung to allow to understand what is the best score to be used. In addition, we explore whether LU-incorporated clinical variables could improve the predictive value for BPD.

Lung Ultrasound in Pediatrics and Neonatology: An Update

The potential role of ultrasound for the diagnosis of pulmonary diseases is a recent field of research, because, traditionally, lungs have been considered unsuitable for ultrasonography for the high presence of air and thoracic cage that prevent a clear evaluation of the organ. The peculiar anatomy of the pediatric chest favors the use of lung ultrasound (LUS) for the diagnosis of respiratory conditions through the interpretation of artefacts generated at the pleural surface, correlating them to disease-specific patterns. Recent studies demonstrate that LUS can be a valid alternative to chest X-rays for the diagnosis of pulmonary diseases, especially in children to avoid excessive exposure to ionizing radiations. This review focuses on the description of normal and abnormal findings during LUS of the most common pediatric pathologies. Current literature demonstrates usefulness of LUS that may become a fundamental tool for the whole spectrum of lung pathologies to guide both diagnostic and therapeutic decisions.

Can lung ultrasound score accurately predict the need for surfactant replacement in preterm neonates? A systematic review and meta-analysis protocol

Respiratory distress syndrome (RDS) is a leading cause of morbidity and mortality in preterm infants due to primary surfactant deficiency. Surfactant replacement has greatly improved the short and long term prognosis of RDS but its administration criteria remain uncertain. Lung ultrasound has been recently shown as a non-invasive, repeatable, bedside tool to estimate parenchymal aeration using a semiquantitative score (LUS). The objective of this systematic review and meta-analysis is to evaluate the accuracy of LUS, assessed on the first day of life, to predict surfactant replacement. Methods will follow the Preferred Reporting Items for Systematic Review and Meta-Analysis Protocols (PRISMA-P) guidelines and the protocol has been registered in PROSPERO database (registration number: CRD42021247888). Primary outcome: in a population of preterm infants, LUS will be compared in neonates who received surfactant replacement versus those who did not. Secondary outcome will be the accuracy of lung ultrasound score to predict the need for ≥ 2 doses of surfactant.

The Role of Lung Ultrasound in the Management of the Critically Ill Neonate-A Narrative Review and Practical Guide

Lung ultrasound makes use of artifacts generated by the ratio of air and fluid in the lung. Recently, an enormous increase of research regarding lung ultrasound emerged, especially in intensive care units. The use of lung ultrasound on the neonatal intensive care unit enables the clinician to gain knowledge about the respiratory condition of the patients, make quick decisions, and reduces exposure to ionizing radiation. In this narrative review, the possibilities of lung ultrasound for the stabilization and resuscitation of the neonate using the ABCDE algorithm will be discussed.

Quantitative Lung Ultrasound: Technical Aspects and Clinical Applications

Lung ultrasound is increasingly used in emergency departments, medical wards, and critical care units-adult, pediatric, and neonatal. In vitro and in vivo studies show that the number and type of artifacts visualized change with lung density. This has led to the idea of a quantitative lung ultrasound approach, opening up new prospects for use not only as a diagnostic but also as a monitoring tool. Consequently, the multiple scoring systems proposed in the last few years have different technical approaches and specific clinical indications, adaptable for more or less time-dependent patients. However, multiple scoring systems may generate confusion among physicians aiming at introducing lung ultrasound in their clinical practice. This review describes the various lung ultrasound scoring systems and aims to clarify their use in different settings, focusing on technical aspects, validation with reference techniques, and clinical applications.

Lung ultrasound features and relationships with respiratory mechanics of evolving BPD in preterm rabbits and human neonates

Evolving broncho-pulmonary dysplasia (BPD) is a regionally heterogeneous disorder characterized by impaired alveolarization leading to lung aeration inhomogeneities. Hyperoxia-exposed preterm rabbits have been proposed to mimic evolving BPD and we aim to verify if this model has the same lung ultrasound and mechanical features of evolving BPD in human neonates. Twenty-five preterm rabbits and twenty-five neonates with evolving BPD were enrolled and subjected to semi-quantitative lung ultrasound and lung mechanics measurement. A modified rabbit lung ultrasound score (rLUS), the previously validated neonatal lung ultrasound score (LUS) and classical mechanics measurements were obtained. Lung ultrasound images were also recorded and evaluated by two independent observers with different expertise blinded to each other's evaluation. Lung ultrasound findings were equally heterogeneous both in rabbits as in human neonates: images were very similar and encompassed all the classical lung ultrasound semiology. The inter-rater absolute agreement for the evaluation of lung ultrasound images in rabbits was very high (ICC: 0.989 (95%CI: 0.975-0.995); p<0.0001) and there was no difference between the two observers. Lung mechanics parameters were similarly altered both in rabbits and human neonates. There were significant correlations between airway resistances and lung ultrasound scores both in rabbits (r=0.519; p=0.008) and in neonates (r=0.409; p=0.042). No significant correlation between rLUS, LUS and any other mechanics parameter. Lung ultrasound was easy to be performed and accurate even in these small animals and with a short training. In conclusion, the preterm rabbit model fairly reproduces the lung ultrasound and mechanical characteristics of preterm neonates with evolving BPD.

Lung ultrasound to predict pediatric intensive care admission in infants with bronchiolitis (LUSBRO study)

It is extremely difficult to stratify bronchiolitis and predict the need for admission to the pediatric intensive care unit (PICU). We aimed to evaluate the capacity of a new lung ultrasound score (LUSBRO) to predict the need for admission to the PICU compared to a clinical score. This was a prospective observational single-center study that includes infants < 6 month of age admitted to a hospital due to acute bronchiolitis. Both scores were calculated at admission. The main outcome was PICU admission. Second endpoints were the need for mechanical ventilation, respiratory support duration, and the length of stay in the hospital. Eighty patients were included, with a median age of 53 days (IQR 29-115). Forty-four patients (55%) required PICU admission. LUSBRO score showed a better AUC compared to the clinical score to predict PICU admission: 0.932 (95% CI 0.873-0.990) vs. 0.675 (95% CI 0.556-0.794) and a positive correlation with the hospital length of stay. The best cut-off point for predicting the need for PICU admission for LUSBRO score was 6, showing a sensitivity of 90.91% and a specificity of 88.89%.Conclusions: The LUSBRO score is a useful tool to predict the need for admission to the PICU. What is Known • It is extremely difficult to stratify which patients affected by bronchiolitis should be precociously transferred to a third level hospital and will require pediatric intensive care unit (PICU) admission. • Clinical scores have been created but neither of them is accurate. What is New • The LUSBRO score is a useful tool to predict the need for admission to the PICU of patients with bronchiolitis and, consequently, to predict the patients who should be transferred to a tertiary hospital to optimize respiratory support.

Neonatal lung diseases: lung ultrasound or chest x-ray

Chest X-ray (CXR) examination is a well-recognized imaging modality in the diagnosis of neonatal lung diseases. On the other hand, lung ultrasound (LUS) has been an emerging and increasingly studied modality. However, the role of LUS as well as its potential to replace CXRs in the detection of neonatal lung diseases has been debated. We combine the present research progress and our own clinical experience to elaborate on various aspects of the potential routine use of lung ultrasound in neonatal intensive care units. We conclude that both LUS and CXR have a number of advantages and disadvantages. They should serve as complementary diagnostic methods in providing accurate, timely, and reliable information.

Lung Ultrasound Score Progress in Neonatal Respiratory Distress Syndrome

BACKGROUND AND OBJECTIVES

The utility of a lung ultrasound score (LUS) has been described in the early phases of neonatal respiratory distress syndrome (RDS). We investigated lung ultrasound as a tool to monitor respiratory status in preterm neonates throughout the course of RDS.

METHODS

Preterm neonates, stratified in 3 gestational age cohorts (25-27, 28-30, and 31-33 weeks), underwent lung ultrasound at weekly intervals from birth. Clinical data, respiratory support variables, and major complications (sepsis, patent ductus arteriosus, pneumothorax, and persistent pulmonary hypertension of the neonate) were also recorded.

RESULTS

We enrolled 240 infants in total. The 3 gestational age intervals had significantly different LUS patterns. There was a significant correlation between LUS and the ratio of oxygen saturation to inspired oxygen throughout the admission, increasing with gestational age (b = -0.002 [P < .001] at 25-27 weeks; b = -0.006 [P < .001] at 28-30 weeks; b = -0.012 [P < .001] at 31-33 weeks). Infants with complications had a higher LUS already at birth (12 interquartile range 13-8 vs 8 interquartile range 12-4 control group; P = .001). In infants 25 to 30 weeks' gestation, the LUS at 7 days of life predicted bronchopulmonary dysplasia with an area under the curve of 0.82 (95% confidence interval 0.71 to 93).

CONCLUSIONS

In preterm neonates affected by RDS, the LUS trajectory is gestational age dependent, significantly correlates with the oxygenation status, and predicts bronchopulmonary dysplasia. In this population, LUS is a useful, bedside, noninvasive tool to monitor the respiratory status.

Modified lung ultrasound score predicts ventilation requirements in neonatal respiratory distress syndrome

Background

We propose a modified lung ultrasound (LUS) score in neonates with respiratory distress syndrome (RDS), which includes posterior instead of lateral lung fields, and a 5-grade rating scale instead of a 4-grade rating scale. The purpose of this study was to evaluate the reproducibility of the rating scale and its correlation with blood oxygenation and to assess the ability of early post-birth scans to predict the mode of respiratory support on day of life 3 (DOL 3). As a secondary objective, the weight of posterior scans in the overall LUS score was assessed.

Methods

We analyzed 619 serial lung scans performed in 70 preterm infants < 32 weeks gestation and birth weight < 1500 g. Assessments were performed within 24 h of birth (LUS₀) and on days 2, 3, 5, 7, 10, 14, 21 and 28. LUS scores were correlated with oxygen saturation over fraction of inspired oxygen (S/F) and mode of respiratory support. Interrater agreement was determined with the intraclass correlation coefficient (ICC) and Cronbach’s alpha. Probabilities of the need for various respiratory support modes on DOL 3 were assessed with ordinal logistic regression. Least square (ls) means of the posterior and anterior pulmonary field scores were compared.

Results

The LUS score correlated significantly with S/F (Spearman rho = −0.635; p < 0.0001) and had excellent interrater agreement (ICC = 0.94, 95% CI 0.93–0.95; Cronbach’s alpha = 0.99). Significant predictors of ventilation requirements on DOL 3 were LUS₀ (p < 0.016) and birth weight (BW) (p < 0.001). In the ROC analysis, LUS₀ had high reliability in prognosing invasive ventilation on DOL 3 (AUC = 0.845 (95% DeLong CI: 0.738–0.951; p < 0.001)). Invasive ventilation was the most likely mode of respiratory support for LUS₀ scores: ≥7 (in infants with BW 900 g), ≥ 10 (in infants with BW 1050 g) and ≥ 15 (in infants with BW 1280 g). Posterior fields exhibited significantly higher average scores than anterior fields. Respective ls means (confidence levels) were 4.0 (3.8–4.1) vs. 2.2 (2.0–2.4); p < 0.001.

Conclusions

Post-birth LUS predicts ventilation requirements on DOL 3. Scores of posterior pulmonary fields have a predominant weight in the overall LUS score.

Ultrasound for Endotracheal Tube Tip Position in Term and Preterm Infants

BACKGROUND AND OBJECTIVE

Placing an endotracheal tube (ETT) in neonates is challenging and currently requires timely radiographic confirmation of correct tip placement. The objective was to establish the reliability of ultrasound (US) for assessing ETT position in the neonatal intensive care unit (NICU), time needed to do so, and patients' tolerance.

METHODS

A prospective study on 71 newborns admitted to our NICU whose ETT placement was evaluated with US (ETT-echo) and confirmed on chest X-rays (CXR). Data were collected by 3 operators (2 neonatologists and a resident in pediatrics). The right pulmonary artery (RPA) was used as a landmark for US. The distance between the tip of the ETT and the upper margin of the RPA was measured using US and compared with the distance between the tube's tip and the carina on the CXR.

RESULTS

Seventy-one intubated newborns were included in the study (n = 34 < 1,000 g, n = 18 1,000-2,000 g, n = 19 > 2,000 g). Statistical analysis (Bland-Altman plot and Lin's concordance correlation coefficient) showed an excellent consistency between ETT positions identified on US and chest X-ray. The 2 measures (ETT-echo and CXR) were extremely concordant both in the whole sample and in the subgroups. Minimal changes in patients' vital signs were infrequently observed during US, confirming the tolerability of ETT-echo. The mean time to perform US was 3.2 min (range 1-13).

CONCLUSIONS

ETT-echo seems to be a rapid, tolerable, and highly reliable method worth further investigating for future routine use in neonatology with a view to reducing radiation exposure.

Lung ultrasound features predict admission to the neonatal intensive care unit in infants with transient neonatal tachypnoea or respiratory distress syndrome born by caesarean section

We aimed to evaluate the reliability of lung ultrasound (LU) to predict admission to the neonatal intensive care unit (NICU) for transient neonatal tachypnoea or respiratory distress syndrome in infants born by caesarean section (CS). A prospective, observational, single-centre study was performed in the delivery room and NICU of Sant'Orsola-Malpighi Hospital in Bologna, Italy. Term and late-preterm infants born by CS were included. LU was performed at 30' and 4 h after birth. LU appearance was graded according to a previously validated three-point scoring system (3P-LUS: type-1, white lung; type-2, black/white lung; type-3, normal lung). Full LUS was also calculated. One hundred infants were enrolled, and seven were admitted to the NICU. The 5 infants with bilateral type-1 lung at birth were all admitted to the NICU. Infants with type-2 and/or type-3 lung were unlikely to be admitted to the NICU. Mean full-LUS was 17 in infants admitted to the NICU, and 8 in infants not admitted. In two separate binary logistic regression models, both the 3P- and the full LUS proved to be independently associated with NICU admission (OR [95% CI] 0.001 [0.000-0.058], P = .001, and 2.890 [1.472-5.672], P = .002, respectively). The ROC analysis for the 3P-LUS yielded an AUC of 0.942 (95%CI, 0.876-0.979; P<.001), while ROC analysis for the full LUS yielded an AUC of 0.978 (95%CI, 0.926-0.997; P<.001). The AUCs for the two LU scores were not significantly different (p = .261).Conclusion: the 3P-LUS performed 30 min after birth proved to be a reliable tool to identify, among term and late preterm infants born to CS, those who will require NICU admission for transient neonatal tachypnoea or respiratory distress syndrome. What is known • Lung ultrasound (LU) has become an attractive diagnostic tool in neonatal settings, and guidelines on point-of-care LU in the neonatal intensive care unit (NICU) have been recently issued. • LU is currently used for diagnosing several neonatal respiratory morbidities and has been also proposed for predicting further intervention, such as NICU admission, need for surfactant treatment or mechanical ventilation in preterm infants. What is new • LU performed 30' after birth and evaluated through a simple three-point scoring system represents a reliable tool to identify, among term and late preterm infants born to caesarean section, those with transient neonatal tachypnoea or respiratory distress syndrome who will require NICU admission. • LU performed in the neonatal period confirms its potential role in ameliorating routine neonatal clinical management.