Routine application of lung ultrasonography in the neonatal intensive care unit

Point-of-care abdominal ultrasound in pediatric and neonatal intensive care units

A spectrum of critical abdominal pathological conditions that might occur in neonates and children warrants real-time point-of-care abdominal ultrasound (abdominal POCUS) assessment. Abdominal radiographs have limited value with low sensitivity and specificity in many cases and have no value in assessing abdominal organ perfusion and microcirculation (Rehan et al. in Clin Pediatr (Phila) 38(11):637-643, 1999). The advantages of abdominal POCUS include that it is non-invasive, easily available, can provide information in real-time, and can guide therapeutic intervention (such as paracentesis and urinary bladder catheterization), making it a crucial tool for use in pediatric and neonatal abdominal emergencies (Martínez Biarge et al. in J Perinat Med 32(2):190-194, 2004) and (Alexander et al. in Arch Dis Child Fetal Neonatal Ed 106(1):F96-103, 2021).  Conclusion: Abdominal POCUS is a dynamic assessment with many ultrasound markers of gut injury by two dimensions (2-D) and color Doppler (CD) compared to the abdominal X-ray; the current evidence supports the superiority of abdominal POCUS over an abdominal X-ray in emergency situations. However, it should still be considered an adjunct rather than replacing abdominal X-rays due to its limitations and operator constraints (Alexander et al. in Arch Dis Child Fetal Neonatal Ed 106(1):F96-103, 2021). What is Known: • Ultrasound is an important modality for the assessment of abdominal pathologies. What is New: • The evidence supports the superiority of abdominal POCUS over an abdominal X-ray in emergency abdominal situations in the neonatal and pediatric intensive care units.

The Impact of Respiratory Therapist Performed Point-of-Care Lung Ultrasound on the Respiratory Care in Neonates, Manitoba Experience, Canada

OBJECTIVE

 We aimed to evaluate the impact of the registered respiratory therapist (RRT) performed point-of-care lung ultrasound (POC-LUS) on patient management in the neonatal intensive care unit (NICU).

STUDY DESIGN

 This is a retrospective cohort study of neonates who had RRT performed POC-LUS in two level III NICUs in Winnipeg, Manitoba, Canada. The analysis aims mainly to describe the implementation process of the POC-LUS program. The primary outcome was the prediction of the change in clinical management.

RESULTS

 A total of 136 neonates underwent 171 POC-LUS studies during the study period. POC-LUS resulted in a change in clinical management following 113 POC-LUS studies (66%), while it supported continuing the same management in 58 studies (34%). The lung ultrasound severity score (LUSsc) was significantly higher in the group with worsening hypoxemic respiratory failure and on respiratory support than infants on respiratory support and stable or not on respiratory support, p < 0.0001. LUSsc was significantly higher in infants on either noninvasive or invasive than those not on respiratory support, p-value <0.0001.

CONCLUSION

 RRT performed POC-LUS service utilization in Manitoba improved and guided the clinical management of a significant proportion of patients who received the service.

Progress in the Application of Lung Ultrasound for the Evaluation of Neonates with Respiratory Distress Syndrome

Neonatal respiratory distress syndrome (NRDS) is a common critical disease in neonates. Early diagnosis and timely treatment are crucial. Historically, X-ray imaging was the primary method for diagnosing NRDS. However, this method carries radiation exposure risks, making it unsuitable for dynamic lung condition monitoring. In addition, neonates who are critically ill require bedside imaging, but diagnostic delays are often unavoidable due to equipment transportation and positioning limitations. These challenges have been resolved with the introduction of lung ultrasound (LUS) in neonatal intensive care. The diagnostic efficacy and specificity of LUS for NRDS is superior to that of X-ray. The non-invasive, dynamic, and real-time benefits of LUS also allow for real-time monitoring of lung changes throughout treatment for NRDS, yielding important insights for guiding therapy. In this paper, we examine the ultrasonographic characteristics of NRDS and the recent progress in the application of ultrasound in the diagnosis and treatment of NRDS while aiming to promote wider adoption of this method.

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.

Sonographic assessment of diaphragmatic thickness and excursion to predict CPAP failure in neonates below 34 weeks of gestation: A prospective cohort study

BACKGROUND

To evaluate the diagnostic accuracy of sonographic assessment of diaphragmatic dimensions and excursions in predicting Continuous Positive Airway Pressure (CPAP) failure in preterm neonates with respiratory distress.

METHODS

Prospective cohort study among preterm neonates less than 34 weeks of gestation who were hemodynamically stable and either admitted with respiratory distress or who developed respiratory distress shortly after admission to the NICU and having Silverman-Anderson Score (SAS) ≥ 3/10 were included. We performed sonographic assessment of diaphragmatic dimensions and excursions before and one hour ±30 minutes after application of CPAP. 'CPAP failure' was defined as combined outcome of the need of surfactant and/or upgradation of respiratory support within first 72 hours after a trial of CPAP. Clinical parameters and diaphragmatic measurements were compared between CPAP failure and success groups.

RESULTS

Of 62 participants, 20 (32%) failed CPAP. On binomial logistic regression (after adjustment for gestational age and birth weight), initial SAS, higher diaphragmatic excursion (both left and right, before and after CPAP application), lower left hemidiaphragm diaphragmatic thickness fraction (DTF) (before CPAP application) and lower right DTF (after CPAP application) were independent predictors of CPAP failure. However, the receiver-operating characteristics curves showed that excursions of right and left hemi-diaphragm both before and after CPAP application, had highest accuracies in predicting CPAP failure (AUC 0.84, 0.80 and 0.86, 0.78, respectively; p < .001).

CONCLUSION

Diaphragmatic excursion can be a useful parameter to predict the failure of CPAP in preterm neonates with respiratory distress.

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

OBJECTIVE

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

METHODS

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

RESULTS

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

CONCLUSION

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

Lung ultrasound description of a newborn with bronchial atresia: A case report

Introduction

Congenital pulmonary malformations are a heterogeneous group of embryological alterations at different stages of lung development, the most frequent being the congenital malformation of the airway. Lung ultrasound is a very useful tool in neonatal intensive care units, providing great value for differential diagnosis, as well as therapeutic response or early detection of complications.

Case Report

The case is a newborn of 38weeks' gestation who was followed by prenatal ultrasound control for suspected adenomatous cystic malformation type III in the left lung from week 22. She did not present complications during pregnancy. The study of Genetics and serological test were negative. She was born by urgent caesarean section due to breech presentation without requiring resuscitation, weighing 2.915 g. She was admitted to the Unit for study, remaining stable throughout her stay, with a normal physical examination. Atelectasis of the left upper lobe was appreciated by chest X-ray. Pulmonary ultrasound on the second day of life showed signs of consolidation in the left posterosuperior field with air bronchogram, without other alterations. In subsequent ultrasound controls, an interstitial infiltrate was observed in the left posterosuperior region, compatible with progressive aeration of the area, which was maintained until 1 month of life. The computed tomographic scan performed at 6months of age shows hyperlucency and increased volume in the left upper lobe with slight hypovascularization, accompanied by paramediastinal subsegmental atelectasis. There was a hypodense image at the hilar level. These findings were compatible with bronchial atresia, later confirmed by fiberoptic bronchoscopy. At 18months of age, surgical intervention was performed.

Discussion and Conclusion

We present the first case of bronchial atresia diagnosed by LUS, thus adding new images to the very scarce literature currently available.

Translating Guidelines into Practical Practice: Point-of-Care Ultrasound for Pediatric Critical Care Clinicians

Point-of-care ultrasound (POCUS) is now transitioning from an emerging technology to a standard of care for critically ill children. POCUS can provide immediate answers to clinical questions impacting management and outcomes within this fragile population. Recently published international guidelines specific to POCUS use in neonatal and pediatric critical care populations now complement previous Society of Critical Care Medicine guidelines. The authors review consensus statements within guidelines, identify important limitations to statements, and provide considerations for the successful implementation of POCUS in the pediatric critical care setting.

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

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

Lung Ultrasound in the Early Diagnosis and Management of the Mild Form of Meconium Aspiration Syndrome: A Case Report

MAS is a common cause of neonatal respiratory distress in term and post-term neonates. Meconium staining of the amniotic fluid occurs in about 10-13% of normal pregnancies, and about 4% of these infants develop respiratory distress. In the past, MAS was diagnosed mainly on the basis of history, clinical symptoms, and chest radiography. Several authors have addressed the ultrasonographic assessment of the most common respiratory patterns in neonates. In particular, MAS is characterised by a heterogeneous alveolointerstitial syndrome, subpleural abnormalities with multiple lung consolidations, characterised by a hepatisation aspect. We present six cases of infants with a clinical history of meconium-stained fluid who presented with respiratory distress at birth. Lung ultrasound allowed the diagnosis of MAS in all the studied cases, despite the mild clinical picture. All children had the same ultrasound pattern with diffuse and coalescing B-lines, pleural line anomalies, air bronchograms, and subpleural consolidations with irregular shapes. These patterns were distributed in different areas of the lungs. These signs are specific enough to distinguish between MAS and other causes of neonatal respiratory distress, allowing the clinician to optimise therapeutic management.

Cardiopulmonary Ultrasound Patterns of Transient Acute Respiratory Distress of the Newborn: A Retrospective Pilot Study

Acute transient respiratory distress in the first hours of life is usually defined as transient tachypnea of the newborn (TTN). TTN is a respiratory self-limiting disorder consequent to delayed lung fluid clearance at birth. While TTN is the most common etiology of respiratory distress near term, its pathogenesis and diagnostic criteria are not well-defined. Lung ultrasound and targeted neonatal echocardiography are increasingly being used to assess critically ill infants, although their combined use to improve diagnostic precision in neonatal intensive care units has not yet been described. This retrospective pilot analysis aimed to identify possible cardiopulmonary ultrasound (CPUS) patterns in term and late preterm infants suffering from transient respiratory distress and requiring non-invasive respiratory support. After retrospectively revising CPUS images, we found seven potential sonographic phenotypes of acute neonatal respiratory distress. Up to 50% of the patients presented with signs of increased pulmonary vascular resistance, suggesting that those patients may be diagnosed with mild forms of persistent pulmonary hypertension of the newborn. Approximately 80% of the infants with a history of meconium-stained amniotic fluid displayed irregular atelectasis, indicating that they may have suffered from mild meconium aspiration syndrome. CPUS evaluation may improve accuracy in the approach to the infants presenting with transient acute respiratory distress, supporting communication with the parents and carrying important epidemiological consequences.

Pulmonary Sonography - Neonatal Diagnosis Part 1

Diseases of the respiratory system are among the main problems of premature patients in the neonatal intensive care unit. Radiography of the thorax is the gold standard of imaging. This results in high cumulative radiation exposure with potential negative long-term consequences. Ultrasound examination of thoracic structures represents a promising radiation-free and ubiquitously available alternative.A healthy, ventilated lung can only be imaged via artifacts, since total reflection of the sound waves occurs due to the high impedance difference between tissue and air-filled lung. Pathologies of pleura and subpleural lung tissue lead to changes in the acoustic properties of the tissue and thus to variations in the artifacts that can be imaged. The main sonographic characteristics of pulmonary pathology are: pleural line abnormalities, increased B-lines and comet-tail artifacts, lung consolidations, a visible pulmonary pulse, pleural sliding abnormalities, and visualization of effusions. Deviations from normal sonographic findings can be assigned to specific underlying pathophysiologies, so that conclusions about the disease can be drawn in conjunction with the clinical symptoms.

Lung Ultrasound Role in Diagnosis of Neonatal Respiratory Disorders: A Prospective Cross-Sectional Study

Lung ultrasound (LUS) has become one of the most exciting applications in neonatal point-of-care ultrasound (POCUS), yet still lacks routine clinical use. This study assesses the utility of LUS for neonatal respiratory disorders (NRDs) diagnosis and follow-up compared to chest X-ray (CXR). A prospective cross-sectional study was conducted on 100 neonates having NRDs with a gestational age ≥28 weeks, excluding those having multiple congenital anomalies, chromosomal aberrations, hydrops fetalis and/or heart failure. CXR and LUS were done on admission for diagnosis and were repeated after 7 days, or if needed earlier within the 7 days. The diagnosis of NRDs by CXR and LUS on admission and after 7 days was comparable (p > 0.05). LUS diagnosis sensitivity and specificity for respiratory distress syndrome, pneumonia, meconium aspiration syndrome, pneumothorax and pulmonary atelectasis were 94.7/100%, 97.5/95%, 92.3/100%, 90.9/98.9% and 100/97.8%, respectively. The total agreement between LUS and CXR was 98.5% with 95% CI (0.88 to 0.92). LUS and CXR had considerable agreement in the diagnosis of NRDs. Being a reliable bedside modality of diagnosis and safer than CXR, LUS may be considered an alternative method for the diagnosis of neonates with NRDs.

The specific signs of lung ultrasound to diagnose pulmonary hemorrhage of the newborns: Evidence from a multicenter retrospective case-control study

OBJECTIVES

Pulmonary hemorrhage (PH) is one kind of critical lung diseases in newborn infants, which is the most difficult one to be diagnosed by ultrasound. This study was to investigate the specific ultrasonic signs of PH in order to better diagnose neonatal PH by using lung ultrasound (LUS).

METHODS

A total 168 newborn infants were enrolled in this study, which included PH, pneumonia, meconium aspiration syndrome, and newborns without lung diseases, there were 42 cases in each group. In a quiet state, infants were placed in the supine, lateral or prone position for the examination. Each lung was divided into the anterior, lateral and posterior regions, then each region of both lungs was scanned with the probe perpendicular to the ribs or parallel to the Intercostal spaces.

RESULTS

The major results showed that: (1) the common LUS manifestation of PH includes lung consolidation, air bronchograms, fluid bronchograms, pleural effusion, shred signs, pleural line abnormality and B-lines, while fibrin deposition sign is a rare sign of PH. (2) Co-existing of lung consolidation with fluid bronchograms and pleural effusion is the specific sign of PH with a sensitivity of 81.0%, specificity of 98.4% and the positive predictive value (PPV) was 94.4%. (3) Fibrin deposition sign is an uncommon specific LUS sign of PH with a sensitivity 28.6%, specificity of 100% and the PPV was 100%. (4) Nine patients (21.4%) were diagnosed with PH based on ultrasound findings before oronasal bleeding. (5) The survival rate of infants with PH was 100% in this study.

CONCLUSION

LUS is helpful for the early diagnosis of neonatal PH and may therefore improve the prognosis. The lung consolidation with fluid bronchograms and pleural effusion as well as fibrin deposition sign are specific to diagnose PH by using LUS.

Lung Ultrasound Induction of Pulmonary Capillary Hemorrhage in Neonatal Swine

This study investigated induction of pulmonary capillary hemorrhage (PCH) in neonatal pigs (piglets) using three different machines: a GE Venue R1 point-of-care system with C1-5 and L4-12t probes, a GE Vivid 7 Dimension with a 7L probe and a SuperSonic Imagine machine with an SL15-4 probe and shear wave elastography (SWE). Female piglets were anesthetized, and each was mounted vertically in a warm bath for scanning at two or three intercostal spaces. After aiming at an innocuous output, the power was raised for a test exposure. Hydrophone measurements were used to calculate in situ values of mechanical index (MIIS). Inflated lungs were removed and scored for PCH area. For the C1-5 probe at 50% and 100% acoustical output (AO), a PCH threshold of 0.53 MIIS was obtained by linear regression (r2 = 0.42). The L4-12t probe did not induce PCH, but the 7L probe induced zones of PCH in the scan planes. The Venue R1 automated B-line tool applied with the C1-5 probe did not detect PCH induced by the C1-5 probe as B-line counts. However, when PCH induced by C1-5 and 7L exposures were subsequently scanned with the L4-12t probe using the automated tool, B-lines were counted in association with the PCH. The SWE induced PCH at push-pulse positions for 3, 30 and 300 s of SWE with PCH accumulating at 0.33 mm2/s and an exponential rise to a maximum of 18.4 mm2 (r2 = 0.61). This study demonstrated the induction of PCH by LUS of piglets, and supports the safety recommendation for use of MIs <0.4 in neonatal LUS.

Point of care lung ultrasound service in neonatal intensive care: Five years of experience in Manitoba, Canada

OBJECTIVE

To evaluate the utility of a point of care lung ultrasound (POC-LUS) on patient management in the Neonatal Intensive Care Unit (NICU).

STUDY DESIGN

A retrospective cohort study of neonates who had POC-LUS from 2016 to 2020 in two-level III NICUs in Winnipeg, Manitoba, Canada. The primary outcome was the change in clinical management. The analysis aims mainly to describe the implementation process of the POC-LUS program.

RESULTS

A total of 956 neonates underwent 4076 POC-LUS studies during the study period. The number of POC-LUS studies increased significantly every year, from 316 (in 2016) to 1257 (in 2020) (p < 0.001). POC-LUS resulted in a change in clinical management following 2528 POC-LUS studies (62%), while it supported continuing the same management in 1548 studies (38%).

CONCLUSION

POC-LUS in Manitoba increased since its inception and led to an alteration in the clinical management in a significant proportion of patients who received the service.

Lung ultrasound to quantitatively evaluate extravascular lung water content and its clinical significance

BACKGROUND

As we all know, pulmonary edema can be diagnosed by lung ultrasound (LUS), but how to accurately and quantitatively evaluate lung water content by ultrasound is a difficult problem that needs to be solved urgently. B-line assessment with LUS has recently been proposed as a reliable, noninvasive semiquantitative tool for evaluating extravascular lung water (EVLW). To date, however, there has been no easy quantitative method to evaluate EVLW by LUS.

OBJECTIVE

(1) To explore the feasibility of establishing a rabbit model with increased EVLW by injecting warm normal saline (NS) into the lungs via the endotracheal tube. (2) To establish a simple, accurate and clinically operable method for quantitative assessment of EVLW using LUS. (3) To develop LUS into a resource for guiding the clinical treatment of patients with increased EVLW.

METHODS

Forty-five New Zealand rabbits were randomized into nine groups (n = 5). After anesthesia, each group of rabbits was injected with different amounts of warm sterile NS (0 ml/kg, 2 ml/kg, 4 ml/kg, 6 ml/kg, 8 ml/kg, 10 ml/kg, 15 ml/kg, 20 ml/kg, 30 ml/kg) via the endotracheal tube. Each rabbit was examined by LUS before and after NS injection. At the same time, the spontaneous respiratory rate (RR, breaths per minute), heart rate (HR, bpm) and arterial blood gas (ABG) of the rabbits were recorded. Then, both lungs were dissected to obtain the wet and dry weight and conduct a complete histological examination.

RESULTS

Injecting NS into the lungs through a tracheal tube can successfully establish a rabbit model with increased EVLW. The extent of EVLW increase is related to the volume of NS injected into the lungs. As the EVLW increases, three different types of B-lines can be seen in the LUS. When the NS injection volume is 2-6 ml/kg, comet-tail artifacts and B-lines are the main patterns found on LUS; as additional NS is injected into the lungs, the rabbits' RR gradually increases, while their HR gradually decreases, ABG remains normal or shows mild metabolic acidosis (MA). Confluent B-lines grow gradually but significantly, reaching a dominant position when the NS injection volume reaches 6-8 ml/kg and predominating almost entirely when the NS injection volume is 8-15 ml/kg; at that time, rabbits' RRs and HRs decrease sharply, and the ABG indicated type I respiratory failure (RF).Compact B-lines occur and predominate almost entirely when the NS injection volume reaches 10 ml/kg and 15-20 ml/kg, respectively. At that time, rabbits begin to enter cardiac and respiratory arrest, and ABG shows type II RF and MA.

CONCLUSION

In this study, the establishment of an animal model with increased EVLW confirmed that different lung water content had corresponding manifestations in ultrasound and was associated with different degrees of clinical symptoms, and the study results can be used to guide clinical practice.

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.

Accuracy and Reliability of Lung Ultrasound to Diagnose Transient Tachypnoea of the Newborn: Evidence from a Meta-analysis and Systematic Review

OBJECTIVE

Transient tachypnoea of the newborn (TTN) is one of the most common causes of neonatal respiratory distress (RD) during the newborn period. Chest radiography (CXR) is commonly used to rule out the diagnosis, but TTN is often misdiagnosed as neonatal respiratory distress syndrome (NRDS) on the basis of CXR alone. Increasing evidence suggests that lung ultrasound (LUS) may be a reliable diagnostic tool for transient tachypnoea of the newborn. However, studies of the diagnostic efficiency of LUS are still lacking. This study was aimed to evaluate the accuracy and reliability of LUS for diagnosing TTN by conducting a systematic review and meta-analysis.

STUDY DESIGN

We searched for articles in the Embase, PubMed, and Cochrane Library databases from inception until May 31, 2020. The selected studies were diagnostic accuracy studies that reported the utility of LUS in the diagnosis of TTN. Two researchers independently extracted data and assessed quality using the Quality Assessment of Diagnostic Accuracy Studies-2 (QUADAS-2) tool. Then, we created a bivariate model of mixed effects to calculate the sensitivity and specificity of LUS in diagnosing TTN. A summary receiver operator characteristic (SROC) curve was constructed to summarize the performance characteristics of LUS.

RESULTS

Six studies involving 617 newborns were included in the review. LUS had a pooled sensitivity of 0.98 (confidence interval [CI]: 0.92-1.00) and a specificity of 0.99 (CI: 0.91-1.00). The area under the curve for LUS was 1.00 (0.98-1.0). Meta-regression revealed that LUS had a significant diagnostic accuracy for TTN.

CONCLUSION

The performance of ultrasound for the detection of TTN was excellent. Considering the various advantages of LUS compared with chest radiographs in diagnosing TTN, this study supports the routine use of LUS for the detection of TTN.

KEY POINTS

· Lung ultrasound is a highly accurate diagnostic tool, which may be a viable and superior alternative to CXR, in diagnosing TTN.. · Lung ultrasound can help differentiate TTN from other etiologies of respiratory distress in neonates.. · There are still some controversies on the ultrasound diagnostic criteria of TTN..

Overview of Lung Ultrasound in Pediatric Cardiology

Lung ultrasound (LUS) is increasing in its popularity for the diagnosis of pulmonary complications in acute pediatric care settings. Despite the high incidence of pulmonary complications for patients with pediatric cardiovascular and congenital heart disease, especially in children undergoing cardiac surgery, the use of LUS remains quite limited in these patients. The aim of this review is to provide a comprehensive overview and list of current potential applications for LUS in children with congenital heart disease, post-surgery. We herein describe protocols for LUS examinations in children, discuss diagnostic criteria, and introduce methods for the diagnosis and classification of pulmonary disease commonly encountered in pediatric cardiology (e.g., pleural effusion, atelectasis, interstitial edema, pneumothorax, pneumonia, and diaphragmatic motion analysis). Furthermore, applications of chest ultrasounds for the evaluation of the retrosternal area, and in particular, systematic search criteria for retrosternal clots, are illustrated. We also discussed the potential applications of LUS, including the guidance of interventional procedures, namely lung recruitment and drainage insertion. Lastly, we analyzed current gaps in knowledge, including the difficulty of the quantification of pleural effusion and atelectasis, and the need to differentiate different etiologies of B-lines. We concluded with future applications of LUS, including strain analysis and advanced analysis of diaphragmatic mechanics. In summary, US is an easy, accurate, fast, cheap, and radiation-free tool for the diagnosis and follow-up of major pulmonary complications in pediatric cardiac surgery, and we strongly encourage its use in routine practice.

Specification and guideline for technical aspects and scanning parameter settings of neonatal lung ultrasound examination

Lung ultrasound (LUS) is now widely used in the diagnosis and monitor of neonatal lung diseases. Nevertheless, in the published literatures, the LUS images may display a significant variation in technical execution, while scanning parameters may influence diagnostic accuracy. The inter- and intra-observer reliabilities of ultrasound exam have been extensively studied in general and in LUS. As expected, the reliability declines in the hands of novices when they perform the point-of-care ultrasound (POC US). Consequently, having appropriate guidelines regarding to technical aspects of neonatal LUS exam is very important especially because diagnosis is mainly based on interpretation of artifacts produced by the pleural line and the lungs. The present work aimed to create an instrument operation specification and parameter setting guidelines for neonatal LUS. Technical aspects and scanning parameter settings that allow for standardization in obtaining LUS images include (1) select a high-end equipment with high-frequency linear array transducer (12-14 MHz). (2) Choose preset suitable for lung examination or small organs. (3) Keep the probe perpendicular to the ribs or parallel to the intercostal space. (4) Set the scanning depth at 4-5 cm. (5) Set 1-2 focal zones and adjust them close to the pleural line. (6) Use fundamental frequency with speckle reduction 2-3 or similar techniques. (7) Turn off spatial compounding imaging. (8) Adjust the time-gain compensation to get uniform image from the near-to far-field.

A training plan to implement lung ultrasound for diagnosing pneumonia in children

BACKGROUND

Lung ultrasound (LUS) for critical patients requires trained operators to perform them, though little information exists on the level of training required for independent practice. The aims were to implement a training plan for diagnosing pneumonia using LUS and to analyze the inter-observer agreement between senior radiologists (SRs) and pediatric intensive care physicians (PICPs).

METHODS

Prospective longitudinal and interventional study conducted in the Pediatric Intensive Care Unit of a tertiary hospital. Following a theoretical and practical training plan regarding diagnosing pneumonia using LUS, the concordance between SRs and the PICPs on their LUS reports was analyzed.

RESULTS

Nine PICPs were trained and tested on both theoretical and practical LUS knowledge. The mean exam mark was 13.5/15. To evaluate inter-observer agreement, a total of 483 LUS were performed. For interstitial syndrome, the global Kappa coefficient (K) was 0.51 (95% CI 0.43-0.58). Regarding the presence of consolidation, K was 0.67 (95% CI 0.53-0.78), and for the consolidation pattern, K was 0.82 (95% CI 0.79-0.85), showing almost perfect agreement.

CONCLUSIONS

Our training plan allowed PICPs to independently perform LUS and might improve pneumonia diagnosis. We found a high inter-observer agreement between PICPs and SRs in detecting the presence and type of consolidation on LUS.

IMPACT

Lung ultrasound (LUS) has been proposed as an alternative to diagnose pneumonia in children. However, the adoption of LUS in clinical practice has been slow, and it is not yet included in general clinical guidelines. The results of this study show that the implementation of a LUS training program may improve pneumonia diagnosis in critically ill patients. The training program's design, implementation, and evaluation are described. The high inter-observer agreement between LUS reports from the physicians trained and expert radiologists encourage the use of LUS not only for pneumonia diagnosis, but also for discerning bacterial and viral patterns.

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.

The Role of Lung Ultrasound Before and During the COVID-19 Pandemic: A review article

Lung ultrasound [LUS] has evolved considerably over the last years. The aim of the current review is to conduct a systematic review reported from a number of studies to show the usefulness of [LUS] and point of care ultrasound for diagnosing COVID-19. A systematic search of electronic data was conducted including the national library of medicine, and the national institute of medicine, PubMed Central [PMC] to identify the articles depended on [LUS] to monitor COVID-19. This review highlights the ultrasound findings reported in articles before the pandemic [11], clinical articles before COVID-19 [14], review studies during the pandemic [27], clinical cases during the pandemic [5] and other varying aims articles. The reviewed studies revealed that ultrasound findings can be used to help in the detection and staging of the disease. The common patterns observed included irregular and thickened A-lines, multiple B-lines ranging from focal to diffuse interstitial consolidation, and pleural effusion. Sub-plural consolidation is found to be associated with the progression of the disease and its complications. Pneumothorax was not recorded for COVID-19 patients. Further improvement in the diagnostic performance of [LUS] for COVID-19 patients can be achieved by using elastography, contrast-enhanced ultrasound, and power Doppler imaging.

Usefulness of Lung Ultrasound in Paediatric Respiratory Diseases

Respiratory infection diseases are among the major causes of morbidity and mortality in children. Diagnosis is focused on clinical presentation, yet signs and symptoms are not specific and there is a need for new non-radiating diagnostic tools. Among these, lung ultrasound (LUS) has recently been included in point-of-care protocols showing interesting results. In comparison to other imaging techniques, such as chest X-ray and computed tomography, ultrasonography does not use ionizing radiations. Therefore, it is particularly suitable for clinical follow-up of paediatric patients. LUS requires only 5-10 min and allows physicians to make quick decisions about the patient's management. Nowadays, LUS has become an early diagnostic tool to detect pneumonia during the COVID-19 pandemic. In this narrative review, we show the most recent scientific literature about advantages and limits of LUS performance in children. Furthermore, we discuss the major paediatric indications separately, with a paragraph fully dedicated to COVID-19. Finally, we mention potential future perspectives about LUS application in paediatric respiratory diseases.

Lung Ultrasonography to Diagnose Bronchopulmonary Dysplasia of Premature Infants

Background: Bronchopulmonary dysplasia (BPD) is a common severe respiratory problem in premature infants, and imaging information has important reference value for its diagnosis. Recently, lung ultrasonography (LUS) has been successfully used for the diagnosis and differential diagnosis of neonatal lung diseases (NLDs), but the study of the diagnosis of BPD is still rare. Objectives: The purpose of this study was to investigate the ultrasonographic characteristics of BPD and its value for the diagnosis and differential diagnosis of premature infants’ BPD. Methods: From January 2015 to December 2019, 25 premature infants diagnosed with early-stage BPD and 32 infants diagnosed with late-stage BPD according to their medical history, clinical manifestation, and chest X-ray were included in this study. The LUS examinations were performed on each infant. The LUS findings were recorded and compared with those of 40 premature infants without lung diseases. Results: The gestational age of 25 early-stage BPD infants was 26+1 – 31+6 weeks, and their birth weight was between 730 and 1,810 g. The gestational age of 32 late-stage BPD infants was 26 - 32 weeks, and their birth weight was 750 - 1,760 g. The gestational age of 40 control infants was 25+6 - 32+1 weeks, and their birth weight was 810 - 2,050 g. There was no difference in the proportion of primary lung diseases (including RDS, TTN, pneumonia, etc.) between the three groups. The proportions of infants receiving invasive and/or non-invasive respiratory support at admission in the three groups of early BPD, late BPD, and normal control were 20/25 (80.0%), 26/32 (81.2%), and 33/40 (77.5%), respectively, with no significant difference (P > 0.05). The mechanical ventilation duration over one week in three groups was 15/20 (75%), 21/26 (80.7%), and 24/33 (72.7%), respectively, with no significant difference (P > 0.05). Nonspecific pleural line abnormalities were seen in all early and late BPD patients (100%), alveolar-interstitial syndrome (AIS) in 16 cases (64%) of early BPD and 32 cases of late BPD infants (100%), pleural insect erosion-like change (PIE-like change) in two cases of early-stage BPD infants (8.0%) and 20 cases (62.5%) of late-stage BPD infants, and air vesicle signs (AVS) only in 17 cases of late-stage BPD infants. The sensitivity and specificity of PIE-like change for the diagnosis of late-stage BPD were 62.5% and 92.0%, respectively, and the sensitivity and specificity of AVS for the diagnosis of late-stage BPD were 53.1 and 100%, respectively. Conclusions: Lung ultrasonography is not specific for the diagnosis of early-stage BPD, but has a high reference value and specificity for the diagnosis of late-stage BPD when combined with obvious pulmonary fibrosis and pulmonary vesicle formation, which is mainly manifested by AIS, PIE-like change, and AVS.

The Influence of Xylazine and Clonidine on Lung Ultrasound-Induced Pulmonary Capillary Hemorrhage in Spontaneously Hypertensive Rats

Induction of pulmonary capillary hemorrhage (PCH) by lung ultrasound (LUS) depends not only on physical exposure parameters but also on physiologic conditions and drug treatment. We studied the influence of xylazine and clonidine on LUS-induced PCH in spontaneously hypertensive and normotensive rats using diagnostic B-mode ultrasound at 7.3 MHz. Using ketamine anesthesia, rats receiving saline, xylazine, or clonidine treatment were tested with different pulse peak rarefactional pressure amplitudes in 5 min exposures. Results with xylazine or clonidine in spontaneously hypertensive rats were not significantly different at the three exposure pulse peak rarefactional pressure amplitudes, and thresholds were lower (2.2 MPa) than with saline (2.6 MPa). Variations in LUS PCH were not correlated with mean systemic blood pressure. Similar to previous findings for dexmedetomidine, the clinical drug clonidine tended to increase susceptibility to LUS PCH.

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.

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.

Bedside cardiopulmonary ultrasonography evaluates lung water content in very low-weight preterm neonates with patent ductus arteriosus

BACKGROUND

Patent ductus arteriosus (PDA) is a common congenital heart abnormality in preterm neonates with a high incidence in neonates with very low birth weights. When PDA persists, interstitial lung water content increases, which could lead to abnormal circulation hemodynamics and pulmonary edema. It is important to perform early and reliable assessment of lung water content in very low-weight preterm neonates with persistent PDA.

AIM

To evaluate the role of bedside cardiopulmonary ultrasonography in the lung water content assessment in very low-weight preterm neonates with persistent PDA.

METHODS

From January 2018 to March 2020, 69 very low-weight preterm neonates with echocardiography-confirmed PDA were selected as the PDA group. At the same time, 89 very low-weight preterm neonates without PDA were randomly selected as the control group. All neonates underwent echocardiography and 6-segment lung ultrasonography on the fourth day after birth. The clinical characteristics and main ultrasonography results were compared between the two groups. Pearson’s analysis was used to analyze the correlation between lung ultrasonography score (LUS) and other related clinical and ultrasonography results in all neonates. In the PDA group, PDA diameters were recorded, and the correlation with LUS and left atrium to aortic (LA/AO) dimension ratio were also analyzed. LA/AO ratio is one of the ultrasonic diagnostic criteria for hemodynamically significant PDA. When the ratio is ≥ 1.5, it suggests the possibility of hemodynamic changes in persistent PDA. A receiver operating characteristic curve was established using the sensitivity of LUS to predict the hemodynamic changes in neonates with PDA as the ordinate and 1-specificity as the abscissa.

RESULTS

A total of 158 neonates were enrolled in this study, including 69 in the PDA group and 89 in the control group. There were no statistical differences in sex, gestational age, birth weight, ventilator dependence, hospitalization length and left ventricular ejection fraction between the two groups (P > 0.05). The LUS and LA/AO ratio in the PDA group were higher than those in the control group (P < 0.05), but there was no difference of LUS in neonates with or without use of the ventilator (t = 0.58, P = 0.16). In all cases, LUS was negatively correlated with gestational age (r = -0.28, P < 0.01) and birth weight (r = -0.36, P < 0.01), while positively correlated with the LA/AO ratio (r = 0.27, P < 0.01). In the PDA group, PDA diameter was positively correlated with the LA/AO ratio (r = 0.39, P < 0.01) and LUS (r = 0.31, P < 0.01). Receiver operating characteristic results showed that LUS had the moderate accuracy for predicting hemodynamic changes in PDA (area under the curve = 0.741; sensitivity = 93.75%; specificity = 50.94%).

CONCLUSION

Bedside cardiopulmonary ultrasonography can evaluate lung content in neonates with PDA and predict the possibility of hemodynamic changes in persistent PDA.

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.

Prone versus Supine Position for Lung Ultrasound in Neonates with Respiratory Distress

OBJECTIVE

To study the feasibility of lung ultrasound (LUS) in prone position and to compare it with supine position in neonates with respiratory distress.

STUDY DESIGN

Neonates ≥ 29 weeks of gestational age with respiratory distress requiring respiratory support within first 12 hours of life were enrolled prospectively. First LUS (fLUS) was done in the position infant was nursed (supine or prone), infant's position changed, a second LUS (sLUS) was performed immediately and a third LUS (tLUS) was done 1 to 2 hours later. Primary outcome was the comparison of LUS scores (LUSsc) between fLUS and sLUS.

RESULTS

Sixty-four neonates were enrolled. Common respiratory diagnoses were transient tachypnea of newborn (TTN; 53%) and respiratory distress syndrome (RDS; 41%). LUSsc was different between fLUS and sLUS (fLUSsc 6 [interquatile range: 4, 7] vs. sLUSsc 7 [4, 10], p < 0.001), while there was no difference between the fLUS and tLUS (fLUSsc 6 [4, 7] vs. tLUSsc 5 [3, 7], p = 0.43). Subgroup analysis confirmed similar findings in neonates with TTN, while in babies with RDS, all the three LUSsc were similar.

CONCLUSION

LUS is feasible in prone position in neonates. LUS scores were higher immediately after a change in position but were similar to baseline 1 hour after the change in position.

The new application of point-of-care lung ultrasound in guiding or assisting neonatal severe lung disease treatment based on a case series

Objective: Lung ultrasound (LUS) has been successfully used for neonatal lung disease diagnosis, as a non-invasive, free of radiation tool, the application of point-of-care LUS (POC-LUS) to diagnose lung disease has become a new trend worldwide. This paper was to introduce the new application of LUS to guide or assist the neonatal lung diseases treatment.Methods: Based on case series of our daily routine clinical work, in combining with the latest literatures, we introducing the new using field of POC-LUS in guiding the treatment of uninflated lung disease by bronchoalveolar lavage (BAL), guiding the treatment of severe pleural effusion and pneumothorax, guide the use of and weaning from mechanical ventilation, and in assessing the efficacy of exogenous pulmonary surfactant (PS) therapy.Results: The results of this study showed that the using rate of invasive ventilation and PS were decreased significantly, the duration of invasive ventilation was shortened significantly, the recovery of pleural effusion and pneumothorax were more quickly and safety, and finally a significantly shortened length of hospitalizations was obtained.Conclusions: LUS monitoring had significant effects in guiding the management of neonatal severe lung diseases, which with the worthy of extensive clinical application.

Italian inter-society expert panel position on radiological exposure in Neonatal Intensive Care Units

BACKGROUND

In the recent years, clinical progress and better medical assistance for pregnant women, together with the introduction of new complex technologies, has improved the survival of preterm infants. However, this result requires frequent radiological investigations mostly represented by thoracic and abdominal radiographs in incubators. This document was elaborated by an expert panel Italian inter-society working group (Radiologists, Paediatricians, Medical Physicists) with the aim to assist healthcare practitioners in taking choices involving radiation exposures of new-born infants and to provide practical recommendations about justification and optimization in Neonatal Intensive Care Units. The adherence to these practice recommendations could ensure a high quality and patient safety. More complex and less common radiological practice, such as CT scan or fluoroscopy have been excluded.

METHODS

The consensus was reached starting from current good practice evidence shared by four scientific societies panel: AIFM (Italian Association of Physics in Medicine), SIN (Italian Neonatology Society), SIP (Italian Paediatric Society), SIRM (Italian Medical Radiology Society) in order to guarantee good standard practices for every professional involved in Neonatal Intensive Care Units (NICU). The report is divided into clinical and physical-dosimetric sections: clinical Indications, good practice in radiological exposures, devices, exposure parameters and modalities, patient positioning and immobilization, Reference Diagnostic Levels, operators and patient's radiation protection. Another important topic was the evaluation of the different incubators in order to understand if the consequences of the technological evolution have had an impact on the increase of the dose to the small patients, and how to choose the best device in terms of radiation protection. At the end the working group faced the problem of setting up the correct communication between clinicians and parents following the most recent indications of the international paediatric societies.

RESULTS

Taking into account the experience and expertise of 10 Italian Centres, the guideline sets out the criteria to ensure a high standard of neonatal care in NICU about procedures, facilities, recommended equipment, quality assurance, radiation protection measures for children and staff members and communication on radiation risk.

CONCLUSIONS

This document will allow a standardization of the approach to the exposures in NICU, although oriented to a flexible methodology.

Application of lung ultrasonography in critically ill patients with COVID-19

PURPOSE

Lung ultrasonography (LU) is useful to assess lung lesions and variations at bedside. To investigate the results of LU in severe and critical patients with coronavirus disease 2019 (COVID-19), we performed a single-institution study to evaluate the related lung lesions and variations, and prophylactic strategies, in a large referral and treatment center.

METHODS

We included 91 adult patients with severe and critical COVID-19, namely 62 males and 29 females, with an average age of 59 ± 11 years, who underwent LU. We collected the following patient information: sex, age, days in hospital, and days in ICU. In the ultrasound examinations, we recorded the presence of discrete B lines, confluent B lines, consolidation, pleural thickening, pleural effusion, and pneumothorax (PTX).

RESULTS

Among the 91 severe and critical patients, 59 cases had scattered B lines, 56 cases had confluent B lines, 58 cases had alveolar-interstitial syndrome (AIS), 48 cases had lung consolidation, six cases had pleural thickening, 39 cases had pleural effusion (average depth of the pleural effusion: 1.0 ± 1.5 cm), and 20 patients developed PTX. In the Cox multivariate analysis, there were significant differences in age, hospitalization days, ICU days, and lung consolidation.

CONCLUSION

Lung ultrasonography performed at the bedside can detect lung diseases, such as B lines, PTX, pulmonary edema, lung consolidation, pleural effusion, and variations of these findings. Our findings support the use of LU and measurements for estimating factors, and monitoring response to therapy in severe and critical COVID-19 patients.

Pleural line thickness reference values for preterm and term newborns

BACKGROUND

In lung ultrasound (LUS), the pleural line is an artifact whose thickness depends on the underlying lung pathology. To date there are no published studies on normal values of pleural line thickness (PLT) in newborns.

OBJECTIVE

The aim of our study is to describe normal PLT values in term newborn (TN) and preterm newborn (PTN).

METHODS

We recruited eupneic TN and PTN, under 34 weeks of gestation, on their first 24 hours of life. Newborns presenting any respiratory distress since birth were excluded. LUS was performed in four areas: upper anterior, lower anterior, lateral and posterior. At each location, we measured PLT and values where compared. Intraobserver and interobserver agreement were assessed using the intraclass correlation coefficient (ICC), and the kappa coefficient.

RESULTS

We included 23 TN with a median birth weight of 3365 g (interquartile range [IQR] 3100-3575 g) and a median gestational age of 39 weeks (IQR, 38-40 weeks). In the PTN group, 23 patients were included with a median birth weight of 1350 g (IQR, 1150-1590 g) and a median gestational age of 31 weeks (IQR, 30-32 weeks). Median PLT values were less than 1 mm, and there were no significant differences between groups at any locations, with the exception of the left lower anterior field (0.79 mm [IQR, 0.72-0.89 mm] vs 0.68 mm [IQR, 0.62-0.72 mm]). Intraobserver agreement was high: consistency ICC 0.77 (95% confidence interval [CI], 0.32-0.92) and absolute ICC 0.78 (95% CI, 0.34-0.93). Interobserver agreement was high for the definition of thin pleural line as less than 1 mm.

CONCLUSIONS

TN and asymptomatic PTN have similar PLT values. Overall, PLT in healthy newborns should be less than 1 mm.

Variation of Diagnostic Ultrasound-Induced Pulmonary Capillary Hemorrhage with Fraction of Inspired Oxygen

Pulmonary capillary hemorrhage induction by diagnostic ultrasound (DUS-PCH) was investigated with respect to the influence of the fraction of inspired oxygen (FiO₂). Sprague-Dawley rats were anesthetized with Telazol only (TO) or Telazol plus xylazine (TX), which can enhance DUS-PCH. A linear array probe (10 L, GE Vivid 7 Dimension) was used in B-mode at 7.5 MHz to expose the right lung. FiO₂ at 10%, 20%, 60% and 100% was delivered through a nose cone. On the ultrasound images, the PCH effect was observed as growing comet tail (B-line) artifacts and as subpleural consolidated segments at higher FiO₂. PCH for TO with 20% and 60% FiO₂ were significantly greater (p < 0.05) than for the 10% FiO₂. PCHs with TX at 10% and 20% FiO₂ were significantly greater (p < 0.02) than those for TO anesthesia. Added xylazine and high percentages of FiO₂ reduced PCH thresholds, but xylazine and high percentages of FiO₂ together did not lower the PCH threshold further. The lowest threshold observed, 1.4 MPa, corresponded to an in situ mechanical index of 0.5.

Lung Ultrasound Score Predicts the Extravascular Lung Water Content in Low-Birth-Weight Neonates with Patent Ductus Arteriosus

BACKGROUND Patent ductus arteriosus (PDA) is a common congenital cardiac abnormality in premature infants. In low-birth-weight infants weighing less than 2500 g, if the PDA continues to open, abnormal circulation hemodynamics and pulmonary edema may occur. This study aimed to investigate the role of lung ultrasound score in the assessment of pulmonary edema in low-weight neonates with PDA. MATERIAL AND METHODS Two hundred and twenty-one neonates with low birth weight were selected as the subjects, children with PDA as the observation group, and children with closed ductus arteriosus as the control group. On the fourth postnatal day, lung ultrasound examination and 6-segment lung ultrasound scoring were performed. RESULTS All 221 infants (94 in the observation group, 127 controls) underwent ultrasound examinations of the lungs. Intergroup differences in gestational age, birth weight, length of hospital stay, and left ventricular ejection fraction were not statistically significant. There was a significant difference in lung ultrasound score (t=0.005, P=0.000) and aortic root ratio to left atrial (t=0.085, P=0.000), which was negatively correlated with gestational age (r=-0.235, P=0.000) and positively correlated with PDA diameter (r=0.261, P=0.011). CONCLUSIONS Low-birth-weight children often have PDA. Its continued opening changes the circulation hemodynamics in children. Lung ultrasound score can semi-quantitatively evaluate the extravascular lung water content, identifying the need to intervene and follow up the hemodynamic significance of PDA over time.

Diagnostic Ultrasound Safety Review for Point-of-Care Ultrasound Practitioners

Potential ultrasound exposure safety issues are reviewed, with guidance for prudent use of point-of-care ultrasound (POCUS). Safety assurance begins with the training of POCUS practitioners in the generation and interpretation of diagnostically valid and clinically relevant images. Sonographers themselves should minimize patient exposure in accordance with the as-low-as-reasonably-achievable principle, particularly for the safety of the eye, lung, and fetus. This practice entails the reduction of output indices or the exposure duration, consistent with the acquisition of diagnostically definitive images. Informed adoption of POCUS worldwide promises a reduction of ionizing radiation risks, enhanced cost-effectiveness, and prompt diagnoses for optimal patient care.

Point-of-care ultrasound in the neonatal ICU

PURPOSE OF REVIEW

Point-of-care ultrasound (POCUS) is an emerging clinical tool in the neonatal intensive care unit (NICU). Recent literature describing the use of POCUS for various applications in the NICU has garnered increased interest among neonatologists.

RECENT FINDINGS

Diagnostic applications for POCUS in the NICU include the evaluation and serial monitoring of common pulmonary diseases, hemodynamic instability, patent ductus arteriosus (PDA), persistent pulmonary hypertension of the newborn (PPHN), necrotizing enterocolitis (NEC), and intraventricular hemorrhage (IVH), among others. Procedural applications include vascular access, endotracheal intubation, lumbar puncture, and fluid drainage.

SUMMARY

Experience with POCUS in the NICU is growing. Current evidence supports the use of POCUS for a number of diagnostic and procedural applications. As use of this tool increases, there is an urgent need to develop formal training requirements specific to neonatology, as well as evidence-based guidelines to standardize use across centers.

Tools to assess lung aeration in neonates with respiratory distress syndrome

AIM

Respiratory distress syndrome is a common condition among preterm neonates, and assessing lung aeration assists in diagnosing the disease and helping to guide and monitor treatment. We aimed to identify and analyse the tools available to assess lung aeration in neonates with respiratory distress syndrome.

METHODS

A systematic review and narrative synthesis of studies published between January 1, 2004, and August 26, 2019, were performed using the OVID Medline, PubMed, Embase and Scopus databases.

RESULTS

A total of 53 relevant papers were retrieved for the narrative synthesis. The main tools used to assess lung aeration were respiratory function monitoring, capnography, chest X-rays, lung ultrasound, electrical impedance tomography and respiratory inductive plethysmography. This paper discusses the evidence to support the use of these tools, including their advantages and disadvantages, and explores the future of lung aeration assessments within neonatal intensive care units.

CONCLUSION

There are currently several promising tools available to assess lung aeration in neonates with respiratory distress syndrome, but they all have their limitations. These tools need to be refined to facilitate convenient and accurate assessments of lung aeration in neonates with respiratory distress syndrome.

International evidence-based guidelines on Point of Care Ultrasound (POCUS) for critically ill neonates and children issued by the POCUS Working Group of the European Society of Paediatric and Neonatal Intensive Care (ESPNIC)

BACKGROUND

Point-of-care ultrasound (POCUS) is nowadays an essential tool in critical care. Its role seems more important in neonates and children where other monitoring techniques may be unavailable. POCUS Working Group of the European Society of Paediatric and Neonatal Intensive Care (ESPNIC) aimed to provide evidence-based clinical guidelines for the use of POCUS in critically ill neonates and children.

METHODS

Creation of an international Euro-American panel of paediatric and neonatal intensivists expert in POCUS and systematic review of relevant literature. A literature search was performed, and the level of evidence was assessed according to a GRADE method. Recommendations were developed through discussions managed following a Quaker-based consensus technique and evaluating appropriateness using a modified blind RAND/UCLA voting method. AGREE statement was followed to prepare this document.

RESULTS

Panellists agreed on 39 out of 41 recommendations for the use of cardiac, lung, vascular, cerebral and abdominal POCUS in critically ill neonates and children. Recommendations were mostly (28 out of 39) based on moderate quality of evidence (B and C).

CONCLUSIONS

Evidence-based guidelines for the use of POCUS in critically ill neonates and children are now available. They will be useful to optimise the use of POCUS, training programs and further research, which are urgently needed given the weak quality of evidence available.

Point-of-care lung ultrasound in three neonates with COVID-19

Since March 2020, the world is involved in the COVID-19 pandemic, a disease caused by a novel virus called SARS-CoV-2. Some authors have described the ultrasonographic findings of COVID-19 pneumonia in adults and children, but data on neonates are lacking. Our objective was to describe the ultrasonographic lung pattern on newborns with SARS-CoV-2 infection during the COVID-19 pandemic. Newborns who tested positive for SARS-CoV-2 PCR in respiratory samples and were evaluated with point-of-care lung ultrasound (LU) from March to April 2020 were included. LU was performed bedside by a single investigator at the time of diagnosis and every 48 h during the first week following diagnosis. Six areas were studied. Three neonates were included. Infants' comorbidities included meconium aspiration syndrome, bronchopulmonary dysplasia, and Hirschsprung's disease. One required mechanical ventilation. No deaths occurred. LU showed B-lines, consolidation, and spared areas. No pneumothorax or pleural effusion was observedConclusions: LU could be of value when managing COVID-19 neonates. We describe the findings of lung ultrasound monitoring during the first week following diagnosis in three neonates with SARS-CoV-2 infection. What is known: • Lung ultrasound (LU) is a useful tool in COVID-19 management in adults. To date, no report on LU and neonates with SARS-CoV-2 infection has been published. What is new: • This study adds evidence about LU findings in neonates with SARS-CoV-2 infection.

POC-LUS guiding pleural puncture drainage to treat neonatal pulmonary atelectasis caused by congenital massive effusion

Point of care lung ultrasound (POC-LUS) has played important roles in diagnosing neonatal lung diseases and assisting in their treatment. A newborn infant with severe respiratory distress diagnosed as pulmonary atelectasis caused by congenital massive pleural effusion, whose consolidated lung recruitment after pleural puncture drainage under POC-LUS guidance. Lung ultrasound can be performed easily and timely at bed-side with free of radiation exposure, thus it should be used extensively in the neonatal department.

Accuracy of Ultrasound in Diagnosis of Pneumothorax: A Comparison between Neonates and Adults-A Systematic Review and Meta-Analysis

Objective

The present systematic review and meta-analysis were conducted to investigate the accuracy of ultrasound in the diagnosis of pneumothorax in neonates and adults.

Method

The searches were conducted by two independent researchers (MS and HD) to find the relevant studies published from 01/01/2009 until the end of 01/01/2019. We searched for published literature in the English language in MEDLINE via PubMed, Embase™ via ovid, the Cochrane Library, and Trip database. For literature published in other languages, we searched national databases (Magiran and SID), KoreaMed, and LILACS, and we searched OpenGrey (http://www.opengrey.eu/) and the World Health Organization Clinical Trials Registry (http://who.int/ictrp) for unpublished literature and ongoing studies. The keywords used in the search strategy were pneumothorax or ultrasound or chest ultrasonography or neonate or adult or aerothorax or sensitivity or specificity or diagnostic accuracy. The list of previous study resources and systematic reviews was also searched for identifying the published studies (MS and HD). Analyses were performed using Meta-Disc 1.4.

Results

In total, 1,565 patients (255 neonates, 1212 adults, and 101 pediatrics suspected of pneumothorax) were investigated in 10 studies. The overall specificity of chest ultrasound in the diagnosis of pneumothorax in both populations of adults and neonates was 85.1% at the confidence interval of 95 percent (95% CI 81.1%–88.5%). At the confidence interval of 95 percent, the sensitivity was 98.6% (95% CI 97.7%–99.2%). The diagnostic odds ratio was 387.72 (95% CI 76.204–1972.7). For the diagnosis of pneumothorax in neonates, the ultrasound sensitivity was 96.7% at the confidence interval of 95 percent (95% CI 88.3%–99.6%). At the confidence interval of 95 percent, the specificity was 100% (95% CI 97.7%–100%). For the diagnosis of pneumothorax in adults, the ultrasound sensitivity was 82.9% at the confidence interval of 95 percent (95% CI 78.3–86.9%). At the confidence interval of 95 percent, the specificity was 98.2% (95% CI 97.0%–99.0%). The diagnostic odds ratio was 423.13 (95% CI 45.222–3959.1). Analyzing studies indicated that the sensitivity of “absence lung sliding” sign for the diagnosis of pneumothorax was 87.2% (95% CI 77.7–93.7), and specificity was 99.4% (95% CI 96.5%–100%). DOR was 556.74 (95% CI 100.03–3098.7). The sensitivity of “lung point” sign for the diagnosis of pneumothorax was 82.1% (95% CI 71.7%–89.8%), and the specificity was 100% (at the confidence interval of 95% CI 97.6%–100%). DOR was 298.0 (95% CI 58.893–1507.8).

Conclusion

The diagnosis of pneumothorax using ultrasound is accurate and reliable; additionally, it can result in timely diagnoses specifically in neonatal pneumothorax. Using this method facilitates the therapy process; lack of ionizing radiation and easy operation are benefits of this imaging technique.

A novel training simulator for portable ultrasound identification of incorrect newborn endotracheal tube placement - observational diagnostic accuracy study protocol

Background

Endotracheal tube (ETT) placement is a critical procedure for newborns that are unable to breathe. Inadvertent esophageal intubation can lead to oxygen deprivation and consequent permanent neurological impairment. Current standard-of-care methods to confirm ETT placement in neonates (auscultation, colorimetric capnography, and chest x-ray) are time consuming or unreliable, especially in the stressful resuscitation environment. Point-of-care ultrasound (POCUS) of the neck has recently emerged as a powerful tool for detecting esophageal ETTs. It is accurate and fast, and is also easy to learn and perform, especially on children.

Methods

This will be an observational diagnostic accuracy study consisting of two phases and conducted at the Aga Khan University Hospital in Karachi, Pakistan. In phase 1, neonatal health care providers that currently perform standard-of-care methods for ETT localization, regardless of experience in portable ultrasound, will undergo a two-hour training session. During this session, providers will learn to detect tracheal vs. esophageal ETTs using POCUS. The session will consist of a didactic component, hands-on training with a novel intubation ultrasound simulator, and practice with stable, ventilated newborns. At the end of the session, the providers will undergo an objective structured assessment of technical skills, as well as an evaluation of their ability to differentiate between tracheal and esophageal endotracheal tubes. In phase 2, newborns requiring intubation will be assessed for ETT location via POCUS, at the same time as standard-of-care methods. The initial 2 months of phase 2 will include a quality assurance component to ensure the POCUS accuracy of trained providers. The primary outcome of the study is to determine the accuracy of neck POCUS for ETT location when performed by neonatal providers with focused POCUS training, and the secondary outcome is to determine whether neck POCUS is faster than standard-of-care methods.

Discussion

This study represents the first large investigation of the benefits of POCUS for ETT confirmation in the sickest newborns undergoing intubations for respiratory support.

Trial registration

ClinicalTrials.gov Identifier: NCT03533218. Registered May 2018.