Lung ultrasonography of pulmonary complications in preterm infants with respiratory distress syndrome

Long-term pulmonary outcomes of young adults born prematurely: a Polish prospective cohort study PREMATURITAS 20

BACKGROUND

The long-term consequences of prematurity are often not sufficiently recognized. To address this gap, a prospective cohort study, which is a continuation of the multicenter Polish study PREMATURITAS, was conducted, utilizing unique clinical data from 20 years ago.

OBJECTIVE

The main goal was to evaluate lung function, detect any structural abnormalities using lung ultrasound, and assess psychological well-being in young adults born between 24 and 34 weeks of gestational age (GA). Additionally, the study aimed to investigate potential associations between perinatal risk factors and abnormalities observed in pulmonary function tests (PFTs) during adulthood.

METHODS

The young survivors underwent a comprehensive set of PFTs, a lung ultrasound, along with the quality of life assessment. Information regarding the neonatal period and respiratory complications was obtained from the baseline data collected in the PREMATURITAS study.

RESULTS

A total of 52 young adults, with a mean age of 21.6 years, underwent PFTs. They were divided into two groups based on GA: 24-28 weeks (n = 12) and 29-34 weeks (n = 40). The subgroup born more prematurely had significantly higher lung clearance index (LCI), compared to the other subgroup (p = 0.013). LCI ≥ 6.99 was more frequently observed in the more premature group (50% vs. 12.5%, p = 0.005), those who did not receive prenatal steroids (p = 0.020), with a diagnosis of Respiratory Distress Syndrome (p = 0.034), those who received surfactant (p = 0.026), and mechanically ventilated ≥ 7 days (p = 0.005). Additionally, elevated LCI was associated with the diagnosis of asthma (p = 0.010).

CONCLUSIONS

The findings suggest pulmonary effects due to prematurity persist into adulthood and their insult on small airway function. Regular follow-up evaluations of young survivors born preterm should include assessments of PFTs. Specifically, the use of LCI can provide valuable insights into long-term pulmonary impairment.

Ultrasound diagnosis and grading criteria of neonatal respiratory distress syndrome

Background: Respiratory distress syndrome (RDS) is a common critical lung disease in newborn infants, especially those in premature infants with higher mortality rate. Early and correct diagnosis is the key to improve its prognosis. Previously, the diagnosis of RDS mainly relied on chest X-ray (CXR) findings, and it has been graded into four stages based on the progression and severity of CXR changes. This traditional diagnosing and grading method may lead to high misdiagnosis rate or delayed diagnosis. Recently, using ultrasound to diagnose neonatal lung diseases and RDS is becoming increasingly popular, and the technology is gaining higher sensitivity and higher specificity. The management of RDS under lung ultrasound (LUS) monitoring has achieved significant results, reducing the misdiagnosis rate of RDS, thereby reducing the probability of mechanical ventilation and the use of exogenous pulmonary surfactant, and making the success rate of treatment of RDS up to 100%.Objective: The purpose of the article was to introduce the ultrasound grading methods and criteria of RDS, in order to promote the application of LUS in the diagnosis and treatment of RDS.Methods: Literature (in English and Chinese) on the use of ultrasound in the diagnosis of neonatal RDS between 2008 and 2022 was selected for inclusion in this study.Results: From the collected literature, the use of ultrasound in the diagnosis of RDS is increasing, and people's understanding of the ultrasound imaging findings of RDS is also changing. Among them, the research on ultrasound grading of RDS is the latest progress.Conclusion: Ultrasound is accurate and reliable in the diagnosis and differential diagnosis of RDS. It is of great clinical value to master the ultrasound diagnosis and grading criteria of RDS.

Comparison between lung ultrasonography and chest X-ray in the evaluation of neonatal respiratory distress syndrome

PURPOSE

Respiratory distress syndrome (RDS), also known as hyaline membrane disease, is the most common clinical syndrome encountered among preterm infants, and the complications of the disease account for substantial mortality. Diagnosis of RDS is based on the clinical status of patients in correlation with laboratory parameters and chest X-ray. Lung ultrasound despite its wide use still is not incorporated into diagnostic algorithms. The aim of the study was to evaluate the diagnostic ability of lung ultrasound in diagnosing respiratory distress syndrome as well as in the monitoring of the response to treatment. A secondary aim was to propose a modified ultrasound grading scale.

METHODS

The prospective study included 150 neonates with clinical and radiographic signs of neonatal respiratory distress syndrome within the first 24 h of life, with different gestational age (≤ 35 weeks). Lung ultrasound was performed by two radiologists and correlated with a chest X-ray. Two gradation scales (ultrasound and X-ray) were compared and each scale was correlated with the patient's clinical data.

RESULTS

In comparison between ultrasound findings and X-ray results showed a statistically significant difference in a favor of ultrasound. Based on the presence of subpleural consolidations, further differentiation of ultrasound profiles were made into subgroups and new ultrasound classification have been proposed.

CONCLUSION

Our study showed that lung ultrasound enables the diagnosing of respiratory distress syndrome in premature neonates and also shows a significant correlation with chest X-ray, which is considered as a radiological method of choice for the diagnosis of RDS.

Neonatal cardiorespiratory imaging-a multimodality state-of-the-art review

Advanced cardiorespiratory imaging of the chest with ultrasound (US), computed tomography (CT) and magnetic resonance imaging (MRI) plays an important role in diagnosing respiratory and cardiac conditions in neonates when radiography and echocardiography alone are not sufficient. This pictorial essay highlights the particularities, clinical indications and technical aspects of applying chest US, cardiac CT and cardiorespiratory MRI techniques specifically to neonates, summarising the first session of the European Society of Paediatric Radiology's cardiothoracic task force.

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).

Neonatal POCUS: Embracing our modern day "stethoscope"

The dramatic technologic advancements seen in ultrasound have accelerated the growth of point-of-care ultrasound (POCUS) in medicine. Neonatology has lagged behind other pediatric and adult specialties in incorporating POCUS into clinical practice despite there being numerous applications in cardiac and non-cardiac arenas. Widely available training programs are aiding in improving this situation but significantly more structure and orchestration for neonatal POCUS dissemination will be needed to fully actualize the potential for POCUS to augment its widespread clinical application.

Pediatric lung ultrasonography: current perspectives

Ultrasonography (US) is the workhorse of pediatric imaging; however, lung US is only a recently developed application. US of the lung is based predominantly on the imaging of chest wall-air-fluid interfaces. In this review, we summarize the available literature on applications of lung US in neonatal as well as pediatric care. We describe the imaging appearance of various commonly encountered pathologies including pneumonia and respiratory distress syndrome, among others, and provide illustrative images. Finally, we describe the limitations of the technique that are essential knowledge for radiologists, critical care physicians, sonographers and technologists attempting to use lung US effectively for diagnosis and management.

Lung Ultrasound for Predicting the Respiratory Outcome in Patients with Bronchopulmonary Dysplasia

OBJECTIVE

This study aimed to investigate the utility of lung ultrasound (LUS) with whole chest scanning for predicting respiratory outcomes in patients with bronchopulmonary dysplasia (BPD).

STUDY DESIGN

We performed a prospective observational study. Preterm infants of less than 32 weeks' gestational age requiring oxygen therapy at 28 days of life were included. LUS was performed on day 28, at 36 weeks' postmenstrual age, and at the time of discharge. Each lung was divided into three regions by the anterior and posterior axillary lines and received an LUS score of 0 to 3 points; the total score was obtained by adding the six regional scores. The classification of BPD was determined based on the National Institute of Child and Human Development. The outcomes of this study were the development of moderate-to-severe BPD and the need for home oxygen therapy (HOT).

RESULTS

We enrolled 87 patients; 39, 33, and 15 infants had mild, moderate, and severe BPD, respectively. The LUS score correlated with BPD severity and exhibited an improvement trend with time toward the point of discharge. LUS at 28 days of life predicted moderate-to-severe BPD with an area under the curve of 0.95 (95% confidence interval: 0.91-0.99) and HOT with an area under the curve of 0.95 (95% confidence interval: 0.81-1.0).

CONCLUSION

LUS with whole chest scanning is useful for predicting respiratory outcomes in patients with BPD, as well as for understanding BPD severity or clinical improvement trends.

KEY POINTS

· LUS predicts respiratory outcomes in patients with BPD.. · LUS indicates BPD severity.. · LUS can show clinical improvement with time..

Evaluation of double lung point sign as a marker for transient tachypnoea of the newborn in preterm

Purpose

The study was conducted to diagnose transient tachypnoea of the newborn (TTN) in the early stage using ultrasonography and to estimate the sensitivity and specificity of double lung point (DLP) sign in diagnosing TTN.

Material and methods

The study population included premature neonates with respiratory distress, admitted in the neonatal intensive care unit from December 2017 to June 2019, who fulfilled the inclusion criteria. A total of 100 patients were included in the study, and they underwent lung ultrasonography within 6 hours of birth. Inclusion criteria were as follows: preterm babies born < 37 weeks of gestation presenting with respiratory distress within 6 hours, clinically diagnosed with TTN and other causes like respiratory distress syndrome and pneumonia. Term neonates and neonates with congenital malformations and trauma were excluded from the study. Preterms with respiratory distress were enrolled in the study. Based on the clinical findings and laboratory investigations, clinical diagnosis was made by the paediatrician. After obtaining informed consent, ultrasonography of bilateral chest was performed using a Philips HD7 XE and a Sonoscape S2 portable ultrasound machine with a linear transducer (6-12 MHz) within 6 hours of birth.

Results

The mean gestational age was 33.0 ± 1.9 weeks. Double lung point sign was present in 55 preterm neonates in our study. It was most common in bilateral posterior lung fields. The sensitivity and specificity of DLP in diagnosing TTN was 85% and 100%, respectively.

Conclusions

It was found in our study that double lung point sign is the primary ultrasonographic characteristic of TTN, and ultrasonography can almost accurately diagnose TTN in early stages.

Role of lung ultrasound in diagnosing and differentiating transient tachypnea of the newborn and respiratory distress syndrome in preterm neonates

Aim

To evaluate the accuracy of lung ultrasound in diagnosing and differentiating transient tachypnea of the newborn and respiratory distress syndrome in preterm neonates.

Material and methods

This was a single-center study. From January 2020 to June 2021. A total of 100 preterm neonates, admitted to the neonatal intensive care unit with symptoms of respiratory distress within six hours of birth, including 50 diagnosed with transient tachypnea of the newborn and 50 with respiratory distress syndrome on the basis of clinical examination, laboratory testing, chest X-rays, were recruited in the study. Lung ultrasound was performed in each neonate by a senior radiologist who was blinded to the clinical diagnosis. Lung ultrasound findings in both conditions were analyzed and compared.

Results

Pulmonary edema manifesting as alveolar-interstitial syndrome, double lung point sign and less commonly as white out lungs in the absence of consolidation has 100% sensitivity and specificity in diagnosing transient tachypnea of the newborn. A combination of three signs of consolidation with air or fluid bronchograms, white out lungs and absent spared areas has 100% sensitivity and specificity for diagnosing respiratory distress syndrome. Double lung point sign was seen only in infants suffering from transient tachypnea of the newborn and consolidation with air or fluid bronchograms only in cases of respiratory distress syndrome.

Conclusion

Lung ultrasound can accurately diagnose and reliably differentiate transient tachypnea of the newborn and respiratory distress syndrome in preterm neonates. It has advantages that cannot be replicated by chest radiography. Lung ultrasound may be used as an initial screening tool.

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.

Gravity-induced loss of aeration and atelectasis development in the preterm lung: a serial sonographic assessment

OBJECTIVE

To assess the impact of gravity and time on the changes in the distribution patterns of loss of aeration and atelectasis development in very preterm infants.

STUDY DESIGN

Preterm infants less than 32 weeks gestation were included in this prospective, observational study. Infants were assessed via serial lung ultrasound (LUS) score in four lung zones, performed on days 7, 14, 21, and 28 after birth.

RESULT

Eighty-eight patients were enrolled. There was a significant main effect of gravity (P < 0.001) and time (P = 0.01) on the LUS score between gravity-dependent lungs and non-dependent lungs. Moreover, there was a significant main effect of gravity (P = 0.003) on atelectasis development between the lungs.

CONCLUSION

Gravity and time have an impact on the changes in the distribution patterns of gravity-induced lung injuries in preterm infants.

The Role of Lung Ultrasound as an Early Diagnostic Tool for Need of Surfactant Therapy in Preterm Infants with Respiratory Distress Syndrome

OBJECTIVE

This study aimed to determine the accuracy of neonatal lung ultrasound (LUS) in predicting the need for surfactant therapy compared with chest X-ray (CXR) in preterm infants.

STUDY DESIGN

A prospective double-blind study was conducted in infants with a gestational age <34 weeks with respiratory distress syndrome (RDS) by evaluation with LUS and CXR on admission.

RESULTS

Among 45 preterm infants, the median (interquartile range [IQR]) LUS score was 4 (2-8) in the mild RDS group, whereas it was 10 (IQR: 9-12) in the severe RDS group (p < 0.01). The LUS score showed a significant correlation with the need for total surfactant doses (ρ = 0.855; 95% confidence interval [CI]: 0.801-0.902; p < 0.001). A cut-off LUS score of four predicted the need for surfactant with 96% sensitivity and 100% specificity (area under the curve [AUC]: 1.00; 95% CI: 0.97-1.00; p < 0.01). LUS scores predicted continuous positive airway pressure (CPAP) failure accurately (AUC: 0.804; 95% CI: 0.673-0.935; p = 0.001). A significant correlation was observed between LUS scores and positive end-expiratory pressure levels (ρ = 0.782; p < 0.001). During the study period, the CXR number per infant with RDS decreased significantly when compared with preceding months (p < 0.001). The LUS score in the first day of life did not predict the development of bronchopulmonary dysplasia (AUC: 0.274; 95% CI: 0.053-0.495; p = 0.065).

CONCLUSION

The LUS score in preterm infants accurately predicts the severity of RDS, the need for surfactant and CPAP failure. The routine use of LUS can decrease the frequency of CXRs in the neonatal intensive care units.

KEY POINTS

· LUS is a nonhazardous bedside technique.. · LUS predicts the need for surfactant in preterm infants.. · LUS predicts the severity of RDS better than CXR..

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.

Using pulmonary artery acceleration time to evaluate pulmonary hemodynamic changes on preterm infants with respiratory distress syndrome

BACKGROUND

Pulmonary artery acceleration time (PAAT) is a reliable and non-invasive method for assessing pulmonary hemodynamics. To date, few studies have used PAAT to assess preterm infants, especially those with respiratory distress syndrome (RDS). This study aimed to assess changes in PAAT among preterm infants with RDS undergoing pulmonary surfactant (PS) therapy or not, and determine its potential effects on the pulmonary vascular disease (PVD) outcomes of preterm infants with RDS in the late postnatal period.

METHODS

The risk of RDS was reviewed in 62 preterm infants with a gestational age of 26-31 weeks. The infants receiving PS therapy were allocated to the PS group, and the others were allocated to the control group. PAAT, right ventricular ejection time (RVET), and other ultrasonic parameters at 3 different time points after birth were studied and compared.

RESULTS

Infants in the PS group had a significantly lower PAAT (52.7±5.9 vs. 59.6±8.7; P=0.001) and PAAT/RVET (0.30±0.03 vs. 0.33±0.03; P=0.001) than those in the control group at 36 weeks postmenstrual age (PMA). No significant increases in PAAT/RVET were detected at 3 different times for the PS group (P=0.117), but both PAAT and PAAT/RVET increased significantly with time after birth in the control group (P<0.001).

CONCLUSIONS

Preterm infants with RDS might still have PVD in the late postnatal period and thus require long-term follow-up observation. PAAT appears to be a reliable non-invasive screening measure for evaluating pulmonary hemodynamics in preterm infants with RDS and late PVD.

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.

Lung Ultrasound for the Diagnosis of Neonatal Respiratory Distress Syndrome: A Meta-analysis

Supplemental digital content is available in the text.

Chest radiography is the primary imaging modality used for the assessment of neonatal respiratory distress syndrome (NRDS) in newborns. However, excessively exposing a growing neonate to harmful ionizing radiation may have long-term consequences. Some studies have shown that lung ultrasound (LUS) is helpful in the diagnosis of NRDS. A comprehensive search was carried out using PubMed, Embase, and the Cochrane Library to identify studies in which newborns with clinically suspected NRDS were assessed by LUS. Two investigators independently screened the literature and extracted the data. Any discrepancies were resolved via discussion with the senior author. Study quality was assessed by the Quality Assessment of Diagnostic Accuracy Studies 2 tool, and pooled sensitivity and specificity of various LUS findings for diagnosing NRDS were determined. Summary receiver operating characteristic curve was used to assess the overall performance of LUS. Ten studies with a total of 887 neonates were included in this meta-analysis. There was significant heterogeneity across the included studies. The pooled sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, and diagnostic odds ratio for the diagnosis of NRDS using LUS were 0.92 (95% confidence interval [CI], 0.89–0.94), 0.95 (95% CI, 0.93–0.97), 20.23 (95% CI, 8.54–47.92), 0.07 (95% CI, 0.03–0.14), and 455.30 (95% CI, 153.01–1354.79), respectively. Furthermore, the summary receiver operating characteristic area under the curve was calculated to be 0.9888. The main LUS characteristics of NRDS include bilateral white lung, pleural line abnormalities, and lung consolidation. In summary, LUS is a highly valuable diagnostic technology that complements chest radiography in the diagnosis and follow-up monitoring of NRDS.

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.

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

Lung ultrasound (LUS) is the latest amongst imaging techniques: it is a radiation-free, inexpensive, point-of-care tool that the clinician can use at the bedside. This review summarises the rapidly growing scientific evidence on LUS in neonatology, dividing it into descriptive and functional applications. We report the description of the main ultrasound features of neonatal respiratory disorders and functional applications of LUS aiming to help a clinical decision (such as surfactant administration, chest drainage etc). Amongst the functional applications, we propose SAFE (Sonographic Algorithm for liFe threatening Emergencies) as a standardised protocol for emergency functional LUS in critical neonates. SAFE has been funded by a specific grant issued by the European Society for Paediatric Research. Future potential development of LUS in neonatology might be linked to its quantitative evaluation: we also discuss available data and research directions using computer-aided diagnostic techniques. Finally, tools and opportunities to teach LUS and expand the research network are briefly presented.

Pediatric lung ultrasound - pros and potentials

Lung ultrasound (US) cannot be considered a new diagnostic imaging technique anymore, with some articles dating back 50 years. The question that hovers over it recently is why it is still not widely accepted, like chest radiography. So, have we wasted a lot of time without using lung US, or are we wasting our time using lung US? The main goals of this article are to underline all the advantages, potentials and reasons to use lung US in everyday clinical practice, but also to address the main concerns linked to this imaging tool. From the standpoint of an experienced pediatric radiologist from a tertiary health care children's hospital who has been performing this examination for more than 10 years on a daily basis, this article also addresses the most common applications of lung US, such as detection of pneumonia and neonatal lung diseases.

Lung ultrasound in pediatric radiology - cons

In the 1990s, intensivists suggested a new type of sonography: lung ultrasound, based on artefacts that receive information even from physical acoustic phenomena not directly convertible into images of the human body. They compared the artefacts from the lung zones with no acoustic window with various computed tomography (CT) patterns. They used and still use US as a tool to evaluate patients bedside, i.e. monitoring of lung recruitment. They included Lung ultrasound in what was termed POCUS (Point-of-Care Ultrasound). Lung ultrasound has been progressively extended to paediatrics in general. The most appealing novelty has been the diagnosis of pneumothorax. Lung ultrasound was developed as a support tool for critical patients. Extrapolation with mass diffusion, in the absence of appropriate training, has led to misunderstandings and dangerous therapeutic diagnostic drifts.

The usefulness of respiratory ultrasound assessment for modifying the physiotherapeutic algorithm in children after congenital heart defect surgeries

Background

The aim of the study was to assess the effectiveness and the possible use of diagnostic transthoracic ultrasound of the respiratory tract to qualify patients for therapy and to monitor the effectiveness of physiotherapy in children after cardiac surgeries.

Materials and methods

A total of 103 patients aged between 1 and 12 months who underwent a series of congenital heart surgeries using cardiopulmonary bypass were qualified for the prospective analysis. Point-of-care respiratory ultrasound imaging was performed according to a tailored protocol during the patient’s stay in the intensive care unit. In order to evaluate the method, the obtained findings were subject to comparative analysis against the available radiographic findings with a division into sectors.

Results

The comparative analysis of ultrasonographic and radiographic findings with a division into sectors showed the highest concordance rate (89.6%) for S1L (the apex of the left lung) and the lowest concordance rate (57.0%) for S2L (pericardial region). The highest discordance rate, i.e. when a lesion was detected in radiography (X-ray = 1), but was not confirmed by ultrasound (US = 0), was reported for sectors S1P (right lung apex) – 26.1%, and S2L – 40.0%, whereas the lowest discordance rate was reported for S1L – 7.0%. The highest discordance rate, i.e. when a lesion was shown in ultrasound (US = 1), but was not confirmed by radiography (X-ray = 0) was reported for S3P (the base of the right lung) and S3L (base of the right lung) – 28.3% and 26.1%, respectively.

Conclusions

The author’s protocol for ultrasonographic assessment of the respiratory tract is an optimal tool for determining therapeutic goals, as well as for the assessment of the efficacy of pulmonary physiotherapy. The diagnostic value of ultrasonographic assessment of the respiratory tract and standard radiography in the study group depends on the location of the investigated lung segment.

Chest ultrasound for the diagnosis of paediatric pulmonary diseases: a systematic review and meta-analysis of diagnostic test accuracy

BACKGROUND

Chest ultrasound is an emerging imaging modality, for several paediatric pulmonary diseases.

SOURCES OF DATA

MEDLINE and EMBASE (1946-47 to 10 March 2017) were searched to collect evidence on the diagnostic accuracy of chest ultrasound, compared to other imaging modalities, for the diagnosis of paediatric pulmonary diseases.

AREAS OF AGREEMENT

Eighteen pneumonia studies, comprising 2031 children, were included for meta-analysis; the summary estimate sensitivity was 95.0% (95%CI: 90.7-97.3%) and specificity was 96.1% (95%CI: 89.1-98.7%).

AREAS OF CONTROVERSY

Other pulmonary diseases also yielded high sensitivity and specificity, but a meta-analysis could not be conducted due to a limited number of studies includable, and their heterogeneity.

GROWING POINTS

Chest ultrasound should be considered as a first-line imaging modality for children with suspected pneumonia.

AREAS TIMELY FOR DEVELOPING RESEARCH

Further research should focus on the diagnostic accuracy of chest ultrasound for the diagnosis of paediatric pulmonary diseases, other than pneumonia, comparing against a valid gold standard.

Lung Ultrasound for the Differential Diagnosis of Respiratory Distress in Neonates

BACKGROUND

Respiratory distress (RD) is the most common neonatal illness. Lung ultrasound (LUS) is a technique previously tested in neonatal studies on RD, but literature regarding its routine clinical applicability is still lacking.

OBJECTIVE

To assess the concordance between LUS performed by neonatologists with different training levels and chest X-ray (CXR) for the diagnosis of RD in newborns during the first 24 h of life.

METHODS

We enrolled newborns with RD during the first 24 h of life. Patients underwent LUS and CXR. LUS and CXR diagnosis were compared to evaluate concordance. Twenty percent of patients received two LUS (one from an experienced and one from a novice sonographer) to calculate the interobserver agreement. The difference in time needed to reach a diagnosis with LUS and CXR, and from novice and expert operators, was measured.

RESULTS

We studied 124 patients; 134 diagnoses were reported. The concordance between LUS and CXR diagnosis was 91% (95% CI 86-96%) with a κ statistic of 0.88 (95% CI 0.81-0.94). The median time to diagnosis was shorter for LUS (9.5 min, IQR 5-15) than for CXR (50 min, IQR 33-64) (p < 0.0001). In 25/124 patients, LUS was performed by both novice and experienced sonographers with complete concordance. The median time to diagnosis was shorter for expert (9 min, IQR 5-15) than novice operators (15 min, IQR 10-20) (p < 0.0002).

CONCLUSION

LUS and CXR have a high concordance in the differential diagnosis of neonatal RD in the first 24 h of life. LUS has a shorter operation time than CXR.

Computer simulation analysis of source-detector position for percutaneously measured O2 -gas signal in a three-dimensional preterm infant lung

Further improvements in the clinical care of our most vulnerable patients-preterm infants-are needed. Novel diagnostic and surveillance tools facilitate such advances. The GASMAS technique has shown potential to become a tool to, noninvasively, monitor gas in the lungs of preterm infants, by placing a laser source and a detector on the chest wall skin. It is believed that this technology will become a valuable clinical diagnostic tool for monitoring the lung function of these patients. Today, the technology is, for this application, in an early stage and further investigations are needed. In the present study, a three-dimensional computer model of the thorax of an infant is constructed, from a set of CT images. Light transport simulations are performed to provide information about the position dependence of the laser- and detector probe on the thorax of the infant. The result of the simulations, based on the study method and the specified model used in this work, indicates that measurement geometries in front and on the side of the lung are favorable in order to obtain a good gas absorption signal.

Ultrasound in neonatal lung disease

Lung diseases in neonates can be life-threatening condition and may result in respiratory failure and death. Chest X-ray is a traditional diagnostic technique that results in radiation exposure to patients. Lung ultrasound is a user-friendly imaging technique that has been increasingly used in clinical practice in recent years and presents the advantages of real-time imaging and without radiation. Here we review the sonographic appearances of common neonatal lung diseases and present demonstration of typical cases.

The safety of pulmonary ultrasonography in the neonatal intensive care unit

OBJECTIVE

Introduction: Due to specific anatomy of children are more vulnerable to the carcinogenic effects of ionizing radiation from chest X-rays. Lung ultrasound (LUS) is a validated procedure which can easily be used in diagnosing pathologies of the neonatal lung. However, experimental studies have shown that low frequency ultrasound may induce pulmonary capillary hemorrhage (PCH). Aim of the study: To evaluate the potential relationship between lung ultrasound and pulmonary hemorrhage in very low birth weight infants.

PATIENTS AND METHODS

Patients and methods: We analysed the medical records of very low birth weight infants admitted to our neonatal tertiary centre between 2008 and 2011 (group 1), when CXR was the main procedure used to evaluate the respiratory system, and between 2013 and 2016 (group 2), when LUS became a routine procedure, replacing the chest X-ray.

RESULTS

Results: 297 infants were enrolled in the first group and 286 in the second group, respectively. There was no difference in the frequency of pulmonary hemorrhages between the two groups (p=1). In the first group there was only one episode of PCH and in the second group no PCH was seen. Statistically significant differences were seen in a number of patients with pulmonary hemorrhage risk factors: surfactant administration (p<0.001), mechanical ventilation (p=0.0003), and hemodynamically significant patent ductus arteriosus (p=0.025).

CONCLUSION

Conclusions: Routine lung ultrasound appears to be safe in very low birth weight infants; there were no episodes of pulmonary hemorrhage.

Development of a 3-dimensional tissue lung phantom of a preterm infant for optical measurements of oxygen-Laser-detector position considerations

There is a need to further improve the clinical care of our most vulnerable patients-preterm infants. Novel diagnostic and treatment tools facilitate such advances. Here, we evaluate a potential percutaneous optical monitoring tool to assess the oxygen and water vapor content in the lungs of preterm babies. The aim is to prepare for further clinical studies by gaining a detailed understanding of how the measured light intensity and gas absorption signal behave for different possible geometries of light delivery and receiver. Such an experimental evaluation is conducted for the first time utilizing a specially developed 3-dimensional-printed optical phantom based on a geometry model obtained from computer tomography images of the thorax (chest) of a 1700-g premature infant. The measurements yield reliable signals for source-detector distances up to about 50 mm, with stronger gas absorption signals at long separations and positions related to the lower part of the lung, consistent with a larger relative volume of this. The limitations of this study include the omission of scattering tissue within the lungs and that similar optical properties are used for the wavelengths employed for the 2 gases, yielding no indication on the optimal wavelength pair to use.

Neonatal Ventilator Associated Pneumonia: A Quality Improvement Initiative Focusing on Antimicrobial Stewardship

Background and Aims: Neonatal ventilator associated pneumonia (VAP) is a common nosocomial infection and a frequent reason for empirical antibiotic therapy in NICUs. Nonetheless, there is no international consensus regarding diagnostic criteria and management. In a first step, we analyzed the used diagnostic criteria, risk factors and therapeutic management of neonatal VAP by a literature review. In a second step, we aimed to compare suspected vs. confirmed neonatal VAP episodes in our unit according to different published criteria and to analyze interrater-reliability of chest x-rays. Additionally, we aimed to evaluate the development of VAP incidence and antibiotic use after implementation of multifaceted quality improvement changes regarding antimicrobial stewardship and infection control (VAP-prevention-bundle, early-extubation policy, antimicrobial stewardship rounds). Methods: Neonates until 44 weeks of gestation with suspected VAP, hospitalized at our level-III NICU in Lucerne from September 2014 to December 2017 were enrolled. VAP episodes were analyzed according to 4 diagnostic frameworks. Agreement regarding chest x-ray interpretation done by 10 senior physicians was assessed. Annual incidence of suspected and confirmed neonatal VAP episodes and antibiotic days were calculated and compared for the years 2015, 2016, and 2017. Results: 17 studies were identified in our literature review. Overall, CDC-guidelines or similar criteria, requesting radiographic changes as main criteria, are mostly used. Comparison of suspected vs. confirmed neonatal VAP episodes showed a great variance (20.4 vs. 4.5/1,000 ventilator-days). The interrater-reliability of x-ray interpretation was poor (intra-class correlation 0.25). Implemented changes resulted in a gradual decline in annual VAP incidence and antibiotic days from 2015 compared with 2017 (28.8 vs. 7.4 suspected episodes/1,000 ventilator-days, 5.5 vs. 0 confirmed episodes/1,000 ventilator-days and 211 vs. 34.7 antibiotic days/1,000 ventilation-days, respectively). Conclusion: The incidence of suspected VAP and concomitant antibiotic use is much higher than for confirmed VAP, therefore inclusion of suspected episodes should be considered for accurate evaluation. There is a high diagnostic inconsistency and a low reliability of interpretation of chest x-rays regarding VAP. Implementation of combined antimicrobial stewardship and infection control measures may lead to an effective decrease in VAP incidence and antibiotic use.

Neonatal lung ultrasound exam guidelines

Point-of-care ultrasound (POC-US) is increasingly used especially in emergency and critical-care medicine. It is focused, quick and does not expose patients to ionizing radiation. It encompasses all organ systems and has well-defined indications. Lung ultrasound (LUS) represents one of the most exciting applications in the field of POC-US. It is particularly important to emphasize the role of LUS in neonatology due to the specific pathology inherent in lung immaturity as well as in the particular sensitivity of neonates to repeated radiation exposure. One of the main barriers to the more extensive use of the ultrasound technology is a lack of efficient and attractive training solutions followed by the structured quality-check assurance. In an effort to help bridge this gap, based on the most current literature, we developed creative and intuitive neonatal LUS algorithms. We hope they can serve as a clinical imaging guidelines and a valuable complement to the history and physical exam.

Lung ultrasonography to diagnose pulmonary hemorrhage of the newborn

OBJECTIVES

This study was aimed to investigate the application of lung ultrasound for the diagnosis of pulmonary hemorrhage of the newborn (PHN).

METHODS

From July 2013 to June 2016, 157 neonates were enrolled in the study. They were divided into two groups: a study group of 57 neonates, who were diagnosed with PHN according to their medical history, clinical manifestations and chest X-ray findings, and a control group of 100 neonates with no lung disease. All subjects underwent bedside lung ultrasound in a quiet state in a supine, lateral or prone position, performed by a single expert physician. The ultrasound findings were compared between the two groups.

RESULTS

The lung ultrasound main findings associated with PHN included lung consolidation with air bronchograms with an incidence of 82.5%, a shred sign with an incidence of 91.2%, pleural effusion with an incidence of 84.2% (pleurocentesis confirmed the fluid was really bleeding), atelectasis with a incidence of 33.3%, pleural line abnormalities, as well as disappearing A-lines with an incidence of 100%, and 11.9% of these patients had the main manifestations of alveolar-interstitial syndrome (AIS). The shred sign exhibited a sensitivity of 91.2% and a specificity of 100% in diagnosing PHN.

CONCLUSIONS

Lung ultrasonography is useful and reliable for diagnosing PHN, which is suitable for routine application in the neonatal intensive care unit.

Neonatal respiratory distress syndrome: Chest X-ray or lung ultrasound? A systematic review

BACKGROUND AND AIM

Neonatal respiratory distress syndrome is a leading cause of morbidity in preterm new-born babies (<37 weeks gestation age). The current diagnostic reference standard includes clinical testing and chest radiography with associated exposure to ionising radiation. The aim of this review was to compare the diagnostic accuracy of lung ultrasound against the reference standard in symptomatic neonates of ≤42 weeks gestation age.

METHODS

A systematic search of literature published between 1990 and 2016 identified 803 potentially relevant studies. Six studies met the review inclusion criteria and were retrieved for analysis. Quality assessment was performed before data extraction and meta-analysis.

RESULTS

Four prospective cohort studies and two case control studies included 480 neonates. All studies were of moderate methodological quality although heterogeneity was evident across the studies. The pooled sensitivity and specificity of lung ultrasound were 97% (95% confidence interval [CI] 94-99%) and 91% (CI: 86-95%) respectively. False positive diagnoses were made in 16 cases due to pneumonia (n = 8), transient tachypnoea (n = 3), pneumothorax (n = 1) and meconium aspiration syndrome (n = 1); the diagnoses of the remaining three false positive results were not specified. False negatives diagnoses occurred in nine cases, only two were specified as air-leak syndromes.

CONCLUSIONS

Lung ultrasound was highly sensitive for the detection of neonatal respiratory distress syndrome although there is potential to miss co-morbid air-leak syndromes. Further research into lung ultrasound diagnostic accuracy for neonatal air-leak syndrome and economic modelling for service integration is required before lung ultrasound can replace chest radiography as the imaging component of the reference standard.

Lung Ultrasound for Diagnosing Pneumothorax in the Critically Ill Neonate

OBJECTIVES

To evaluate the accuracy of lung ultrasound for the diagnosis of pneumothorax in the sudden decompensating patient.

STUDY DESIGN

In an international, prospective study, sudden decompensation was defined as a prolonged significant desaturation (oxygen saturation <65% for more than 40 seconds) and bradycardia or sudden increase of oxygen requirement by at least 50% in less than 10 minutes with a final fraction of inspired oxygen ≥0.7 to keep stable saturations. All eligible patients had an ultrasound scan before undergoing a chest radiograph, which was the reference standard.

RESULTS

Forty-two infants (birth weight = 1531 ± 812 g; gestational age = 31 ± 3.5 weeks) were enrolled in 6 centers; pneumothorax was detected in 26 (62%). Lung ultrasound accuracy in diagnosing pneumothorax was as follows: sensitivity 100%, specificity 100%, positive predictive value 100%, and negative predictive value 100%. Clinical evaluation of pneumothorax showed sensitivity 84%, specificity 56%, positive predictive value 76%, and negative predictive value 69%. After sudden decompensation, a lung ultrasound scan was performed in an average time of 5.3 ± 5.6 minutes vs 19 ± 11.7 minutes required for a chest radiography. Emergency drainage was performed after an ultrasound scan but before radiography in 9 cases.

CONCLUSIONS

Lung ultrasound shows high accuracy in detecting pneumothorax in the critical infant, outperforming clinical evaluation and reducing time to imaging diagnosis and drainage.

Diode laser spectroscopy for noninvasive monitoring of oxygen in the lungs of newborn infants

BACKGROUND

Newborn infants may have pulmonary disorders with abnormal gas distribution, e.g., respiratory distress syndrome. Pulmonary radiography is the clinical routine for diagnosis. Our aim was to investigate a novel noninvasive optical technique for rapid nonradiographic bedside detection of oxygen gas in the lungs of full-term newborn infants.

METHODS

Laser spectroscopy was used to measure contents of oxygen gas (at 760 nm) and of water vapor (at 937 nm) in the lungs of 29 healthy newborn full-term infants (birth weight 2,900-3,900 g). The skin above the lungs was illuminated using two low-power diode lasers and diffusely emerging light was detected with a photodiode.

RESULTS

Of the total 390 lung measurements performed, clear detection of oxygen gas was recorded in 60%, defined by a signal-to-noise ratio of >3. In all the 29 infants, oxygen was detected. Probe and detector positions for optimal pulmonary gas detection were determined. There were no differences in signal quality with respect to gender, body side or body weight.

CONCLUSION

The ability to measure pulmonary oxygen content in healthy full-term neonates with this technique suggests that with further development, the method might be implemented in clinical practice for lung monitoring in neonatal intensive care.

Application of Lung Ultrasonography in the Diagnosis of Childhood Lung Diseases

In this paper, we focus on the characteristics of LUS in diagnosing childhood pulmonary disease. LUS is convenient, noninvasive, and free of radiation. It helps in the differentiation of lung diseases. Therefore, LUS has the potential to become a reference instrument for bedside dynamic respiratory monitoring. We hope that this review will help clinicians become acquainted with LUS and will accelerate the extensive application of LUS in children.

Use of lung ultrasound in detection of complications of respiratory distress syndrome

Repeated chest radiography is required for the diagnosis and follow-up of neonates with respiratory distress syndrome (RDS) and carries the risk of radiation hazards. Lung ultrasound (LUS) is a non-invasive bedside diagnostic tool that has proven to be effective in the diagnosis of RDS. Our aim was to assess the role of LUS with respect to the standard chest X-ray (CXR) in the detection of complications of RDS in neonates. Ninety premature newborns of both genders with RDS (mean gestational age = 29.91 ± 1.33 wk) and 40 premature babies as a control group were involved in this study. All patients underwent initial clinical assessment as well as CXR and LUS. Those who presented with respiratory distress and/or exhibited deterioration of oxygenation parameters were followed by CXR and, within 4 h, by LUS. Alveolo-interstitial syndrome and pleural line abnormalities were detected in all cases (100%) in the initial assessment, patchy consolidation was detected in 34 cases and white lung was detected in 80 cases. Alveolo-interstitial syndrome was detected in 19 controls. In follow-up of the patients, LUS was superior to CXR in detection of consolidation and sub-pleural atelectasis, but not in detection of pneumothorax. We concluded that bedside LUS is a good non-hazardous alternative tool in the early detection and follow-up of RDS in the neonatal intensive care unit; it could be of value in reducing exposure to unnecessary radiation.

The irregular diaphragmatic pleural interface: a novel sonographic sign facilitating the diagnosis of pneumonia

Pneumonia, a disease that has been reported to be the sixth leading cause of death in the United States, has worsening mortality with delays in diagnosis. As the history and physical examination are excessively inaccurate in the diagnosis of pneumonia, we often rely on chest radiography to rule in or out disease. However, it is found to lack sufficient accuracy when computed tomography is used as the reference standard. Sonography has emerged as a viable alternative to chest radiography in the diagnosis of pneumonia. Here, we describe a novel sonographic sign that can be used to assist in the diagnosis of pneumonia.

Unilateral atelectasis in a preterm infant monitored with electrical impedance tomography: a case report

Electrical impedance tomography (EIT) is a non-invasive, radiation-free tool to monitor regional changes in ventilation. This report describes, for the first time, that unilateral atelectasis in an extremely low birth weight infant results in a loss of regional ventilation measured by EIT in the affected lung.

CONCLUSION

EIT is currently the most promising technique to monitor regional lung aeration continuously at the bedside in this vulnerable population.

Diagnosis of neonatal transient tachypnea and its differentiation from respiratory distress syndrome using lung ultrasound

Transient tachypnea of the newborn (TTN) is one of the most common causes of perinatal dyspnea and is traditionally diagnosed by chest x-ray. This study aimed to explore the diagnostic value of lung ultrasonography (LUS) for TTN as well as differentiate it from respiratory distress syndrome (RDS) by using LUS. From January 2013 to February 2014, 60 infants who were diagnosed with TTN based on medical history, clinical manifestations, arterial blood gas analysis, and chest radiography were recruited to the study group. During the same period, 40 hospitalized neonates with nonlung diseases and 20 patients with RDS were recruited to the control group. In a quiet state, infants were placed in the supine, lateral, or prone position for the examination. Each lung of every infant was divided into 3 regions: the anterior, lateral, and posterior regions as bordered by the anterior axillary and posterior axillary lines. The probe was placed perpendicular to the ribs. Each region of both the lungs was carefully scanned.The common ultrasonographic manifestations of TTN were double-lung point (DLP), interstitial syndromes or white lungs, pleural line abnormalities, and A-line disappearance. A small number of infants (20%) with TTN exhibited pleural effusions, whereas the main ultrasonographic manifestation of RDS was lung consolidation with air bronchograms, which does not occur in TTN. The sensitivity and specificity of DLP for the diagnosis of TTN were 76.7% and 100%, respectively. LUS can accurately and reliably diagnose TTN. The DLP and lung consolidation possess great value in the diagnosis and differential diagnosis of TTN with RDS. Thus, we believe that LUS can be widely used in neonatal intensive care units.

BPD, Not BPD, or iatrogenic BPD: findings of lung ultrasound examinations

Lung ultrasound has been extensively used to diagnose many types of lung disease. This study aimed to evaluate the pulmonary reasons for long-term oxygen dependence (LTOD) in premature infants using lung ultrasound.Lung ultrasound was routinely performed in 50 premature infants clinically diagnosed with bronchopulmonary dysplasia (BPD).Among the 50 patients studied, there were 9 cases of atelectasis, 4 cases of pneumonia, 2 cases of severe pulmonary edema, and 3 cases of pulmonary edema and consolidation that coexisted with BPD. The oxygen dependence of the babies either completely resolved or significantly decreased following appropriate treatments.More than one-third of the cases of LTOD in premature babies were caused by either BPD alone or diseases other than BPD. Lung ultrasound plays an important role in differentiating pulmonary causes of LTOD in patients with BPD, and the results of our study suggest that modifying the diagnostic criteria for BPD may be necessary.

Lung ultrasound accuracy in respiratory distress syndrome and transient tachypnea of the newborn

BACKGROUND

Lung ultrasound (LUS) is a promising technique for the diagnosis of neonatal respiratory diseases. Preliminary data has shown a good sensitivity and specificity of LUS in the diagnosis of respiratory distress syndrome (RDS) and transient tachypnea of the newborn (TTN).

OBJECTIVE

The aim of this study was to calculate the sensitivity, specificity, and negative (NPV) and positive predictive value (PPV) of LUS for RDS and TTN, using an external reader blinded to the clinical condition.

DESIGN AND METHODS

Neonates with respiratory distress had a LUS within 1 h of admission. Images were uploaded and sent to the external reader, who made the ultrasound diagnosis according to the appearance of the images. The final clinical diagnosis was made according to all the available data, except LUS data. Sensitivity, specificity, PPV, and NPV were calculated considering the final clinical diagnosis as the gold standard.

RESULTS

Fifty-nine neonates were studied (mean gestational age: 33 ± 4 weeks, mean birth weight: 2,145 ± 757 g). Twenty-three infants had a final diagnosis of RDS and 30 of TTN. LUS showed a sensitivity of 95.6% and specificity of 94.4%, with a PPV of 91.6% and a NPV of 97.1% for RDS, and a sensitivity of 93.3% and specificity of 96.5% with a PPV of 96.5% and a NPV of 93.4% for TTN.

CONCLUSIONS

LUS showed high sensitivity and specificity in diagnosing RDS and TTN.