Lung ultrasonography and pediatric cardiac surgery: first experience with a new tool for postoperative lung complications

Lung Ultrasound Findings in Healthy Children and in Those Who Had Recent, Not Severe COVID-19 Infection

Background: Lung ultrasound (LUS) is gaining consensus as a non-invasive diagnostic imaging method for the evaluation of pulmonary disease in children. Aim: To clarify what type of artifacts (e.g., B-lines, pleural irregularity) can be defined normal LUS findings in children and to evaluate the differences in children who did not experience COVID-19 and in those with recent, not severe, previous COVID-19. Methods: LUS was performed according to standardized protocols. Different patterns of normality were defined: pattern 1: no plural irregularity and no B-lines; pattern 2: only mild basal posterior plural irregularity and no B-lines; pattern 3: mild posterior basal/para-spine/apical pleural irregularity and no B-lines; pattern 4: like pattern 3 plus rare B-lines; pattern 5: mild, diffuse short subpleural vertical artifacts and rare B-lines; pattern 6: mild, diffuse short subpleural vertical artifacts and limited B-lines; pattern 7: like pattern 6 plus minimal subpleural atelectasis. Coalescent B-lines, consolidations, or effusion were considered pathological. Results: Overall, 459 healthy children were prospectively recruited (mean age 10.564 ± 3.839 years). Children were divided into two groups: group 1 (n = 336), those who had not had COVID-19 infection, and group 2 (n = 123), those who experienced COVID-19 infection. Children with previous COVID-19 had higher values of LUS score than those who had not (p = 0.0002). Children with asymptomatic COVID-19 had similar LUS score as those who did not have infections (p > 0.05), while those who had symptoms showed higher LUS score than those who had not shown symptoms (p = 0.0228). Conclusions: We report the pattern of normality for LUS examination in children. We also showed that otherwise healthy children who recovered from COVID-19 and even those who were mildly symptomatic had more “physiological” artifacts at LUS examinations.

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.

Chest sonography versus chest radiograph in children admitted to paediatric intensive care - A prospective study

There is a paucity of studies on the correlation between chest radiograph and ultrasound (US) in children. Our objective was to study the correlation between bedside chest radiograph and ultrasound findings in 413 children with 1002 episodes of chest radiograph and US enrolled for a prospective, double-blinded observational study in a multidisciplinary paediatric intensive care unit. Weighted κ statistic for agreement was different for right and left lungs and varied from 50% for left pleural effusion to 98% for right pneumothorax. Pulmonary oedema, pneumothorax and pleural effusion were diagnosed by ultrasound alone in a significantly higher number of patients as compared to chest radiograph (P = 0.001). Chest ultrasound is therefore deemed more sensitive than chest radiograph in detection of pleural effusion, pulmonary oedema and pneumothorax.

Lung Ultrasound: Its Findings and New Applications in Neonatology and Pediatric Diseases

Lung ultrasound has become increasingly used in both adult and pediatric populations, allowing the rapid evaluation of many lung and pleura diseases. This popularity is due to several advantages of the method such as the low cost, rapidity, lack of ionizing radiation, availability of bedside and repeatability of the method. These features are even more important after the outbreak of the SARS-CoV-2 pandemic, given the possibility of recognizing through ultrasound the signs of interstitial lung syndrome typical of pneumonia caused by the virus. The purpose of this paper is to review the available evidence of lung ultrasound (LUS) in children and its main applications in pediatric diseases.

Extracardiac Complications in Intensive Care Units after Surgical Repair for Congenital Heart Disease: Imaging Review with a Focus on Ultrasound and Radiography

Pediatric patients show various extracardiac complications after cardiovascular surgery, and radiography and ultrasound are routinely performed in the intensive care unit to detect and evaluate these complications. This review presents images of these complications, sonographic approach, and timing of occurrence that are categorized based on their extracardiac locations and include complications pertaining to the central nervous system, mediastinum, thorax and lung parenchyma, diaphragm, liver and biliary system, and kidney along with pleural effusion and iatrogenic complications. This pictorial review will make it easier for medical doctors in intensive care units to identify and manage various extracardiac complications in pediatric patients after cardiovascular surgery.

Furosemide: Would it help to improve the lungs as evaluated by sonography and compliance during aortic coarctation surgery

Background

We evaluated furosemide on attenuating lung injury and/or edema during coarctation repair surgery. We evaluated dynamic lung compliance. We measured the degree of lung edema by means of lung ultrasound (LUS). We recorded the (PaO₂/FiO₂ratio) as an indicator for oxygenation.

Materials and Methods

A study was conducted on 56 patients. Patients were divided into two groups: control group (Group C) which did not receive furosemide and furosemide group (Group F) at a dose of 1 mg/kg at induction of anesthesia. Dynamic lung compliance was calculated at induction (Cdyn 1) and at the end of the surgery (Cdyn 2). The (PaO₂/FiO₂ratio) was calculated at start and end of surgery as (PF 1) and (PF 2), respectively. LUS was performed after induction (LUS 1) and at the end of the surgery. LUS 2 using the 12 regions method plotting the results on scale from 0 to 36. Mechanical ventilation days were recorded.

Results

Administering furosemide attenuated the lung injury/edema and other pulmonary complications. Furosemide administration improved the dynamic lung compliance in the F Group compared to the C Group. Furthermore, it increased the (PaO₂/FiO₂ratio) in the F Group compared to the C Group. LUS scale values were lower in the F Group compared to the C Group. There was also less postoperative mechanical ventilation days.

Conclusions

The use of furosemide was accompanied by improved lung injury/edema profile as indicated by a much less drop in dynamic lung compliance, better oxygenation, a more favorable LUS scale with less parenchymal lung affection.

Moving Beyond the Stethoscope: Diagnostic Point-of-Care Ultrasound in Pediatric Practice

Diagnostic point-of-care ultrasound (POCUS) is a growing field across all disciplines of pediatric practice. Machine accessibility and portability will only continue to grow, thus increasing exposure to this technology for both providers and patients. Individuals seeking training in POCUS should first identify their scope of practice to determine appropriate applications within their clinical setting, a few of which are discussed within this article. Efforts to build standardized POCUS infrastructure within specialties and institutions are ongoing with the goal of improving patient care and outcomes.

Getting to know a familiar face: Current and emerging focused ultrasound applications for the perioperative setting

Ultrasound technology is available in many pediatric perioperative settings. There is an increasing number of ultrasound applications for anesthesiologists which may enhance clinical performance, procedural safety, and patient outcomes. This review highlights the literature and experience supporting focused ultrasound applications in the pediatric perioperative setting across varied disciplines including anesthesiology. The review also suggests strategies for building educational and infrastructural systems to translate this technology into clinical practice.

Lung ultrasound reclassification of chest X-ray data after pediatric cardiac surgery

INTRODUCTION

Lung ultrasound is gaining consensus for the diagnosis of some pulmonary conditions. Pulmonary complications are common in pediatric cardiac surgery. However, its use remains limited in this setting. Our aim was to test the feasibility of lung ultrasound following pediatric cardiac surgery and to compare lung ultrasound and chest X-ray findings, assessing whether lung ultrasound may provide additional information.

METHODS

One hundred and thirty-eight lung ultrasound examinations were performed in 79 children (median age 9.3 months) at different time points after surgery. For each hemithorax, 3 areas (anterior/lateral/posterior) have been evaluated in the upper and lower halves of the chest (for a total of 6 scanning sites per side). Pleural effusion, atelectasis, and the number of B-lines were investigated.

RESULTS

Lung ultrasound was feasible in all cases in at least 1 of the 3 areas. Feasibility was different for the lateral, posterior, and anterior areas (100%, 90%, and 78%, respectively). The posterior areas were more sensitive than anterior and lateral ones in the diagnosis of effusion/atelectasis. In 81 cases, lung ultrasound allowed reclassification of chest X-ray findings, including 40 new diagnoses (diagnosis of effusion/atelectasis with negative chest X-ray reports) and 41 changes in diagnosis (effusions reclassified as atelectasis/severe congestion or vice versa). Although new diagnosis of small-to-moderate effusion/atelectasis was of limited clinical value, in 29 cases the new diagnosis changed the therapeutic approach.

CONCLUSION

Lung ultrasound is feasible and accurate for the diagnosis of common pulmonary conditions after pediatric cardiac surgery, allowing reclassification of chest X-ray findings in a significant number of patients.

Utility of Perioperative Lung Ultrasound in Pediatric Cardiac Surgery

Background

Pediatric cardiac patients are at risk for perioperative respiratory insufficiency. The objective of this study was to assess the utility of perioperative lung ultrasound examination in pediatric cardiac surgery.

Methods

In this randomized, controlled trial, children (5 yr old or younger) undergoing cardiac surgery were allocated into a control (n = 61) or intervention (n = 61) group. The control group received only lung ultrasound examinations at the end of surgery and 6 to 12 h after surgery. The intervention group received lung ultrasound examinations and an ultrasound-guided recruitment maneuver depending on ultrasound findings after inducing anesthesia, at the end of surgery, and 6 to 12 h after surgery. Primary outcomes were incidences of intra- and postoperative desaturation, and postoperative pulmonary complications. Multiple comparisons were corrected (P ≤ 0.017) in the primary outcome analysis.

Results

Of the 120 children included in the analysis, postoperative desaturation (64% vs. 27%; P < 0.001; odds ratio [OR], 0.210; 95% CI, 0.097 to 0.456) occurred more in the control group. The incidences of intraoperative desaturation (36% vs. 19%; P = 0.033; OR, 0.406; 95% CI, 0.176 to 0.939) and postoperative pulmonary complications (12% vs. 3%; P = 0.093; OR, 0.271; 95% CI, 0.054 to 1.361) were similar between the groups. Lung ultrasound scores were better in the intervention group than in the control group. Duration of mechanical ventilation was longer in the control group than in the intervention group (38 ± 43 vs. 26 ± 25 h; 95% CI of mean difference, 0 to 25; P = 0.048).

Conclusions

Perioperative lung ultrasound examination followed by ultrasound-guided recruitment maneuver helped decrease postoperative desaturation events and shorten the duration of mechanical ventilation in pediatric cardiac patients.

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.

Assessment of extravascular lung water by ultrasound after congenital cardiac surgery

BACKGROUND

Lung ultrasounds show vertical artifacts known as B-lines in the presence of increased extravascular lung water (EVLW). We aimed to investigate whether lung ultrasound could estimate EVLW after congenital cardiac surgery.

METHODS

This prospective observational study comprised 61 children (age range 3 days to 7.4 years) undergoing congenital cardiac surgery. We compared postoperative B-line scores from lung ultrasounds, early postoperative ultrasound as our primary interest, with corresponding postoperative chest radiography (CXR) lung edema scores, with static lung compliance, and with short-term clinical outcome interpreted as time on mechanical ventilation and length of pediatric intensive care unit (PICU) stay.

RESULTS

Our findings showed lung ultrasound B-line scores and CXR lung edema scores as correlating 1-6 hr postoperatively (r²  = 0.41, P < 0.0001), on the first postoperative day (r²  = 0.15, P = 0.004) and on the fourth postoperative day (r²  = 0.28, P = 0.008). The B-line score or CXR lung edema score showed no correlation with lung compliance. We found that in multivariable analyses, with length of perfusion and presence of postoperative complications as covariates, both lung ultrasound (P ≤ 0.02) and CXR (P ≤ 0.002) 1-6 hr postoperatively predicted the length of mechanical ventilation and PICU stay. The interobserver variability was less for lung ultrasound B-line score than for CXR lung edema score (P = 0.001).

CONCLUSIONS

Our results show that lung ultrasound in assessment of postoperative EVLW predicted length of mechanical ventilation and stay in the PICU, and it had less interobserver variability than CXR. Accordingly, lung ultrasound may complement CXR in assessment of lung edema after surgery for congenital heart defect. Pediatr Pulmonol. 2017;52:345-352. © 2016 Wiley Periodicals, Inc.

Usefulness of Lung Ultrasound in Neonatal Congenital Heart Disease (LUSNEHDI): Lung Ultrasound to Assess Pulmonary Overflow in Neonatal Congenital Heart Disease

This study aimed to explore the pattern of lung ultrasound (LUS) in newborns with congenital heart disease (CHD) and to investigate the accuracy of LUS assessing pulmonary overflow (PO) during the first days of life. Lung ultrasound was performed in 51 newborns during the first days of life, and newborns were classified in two groups depending on the predisposition to develop POas evaluated by the abundance of B-lines. The results were compared to the physical examination (PE), chest X-ray, and echocardiography. In both groups there were no differences in abundance of B-lines during the first days of life, but those with a type of CHD with a trend to develop PO had a higher B-lines score after 72 h (p < 0.05) with a good correlation with echocardiography findings and with a better sensibility than PE and chest X-ray. We found that LUS is a reliable tool for the diagnosis of PO and may be useful to monitor and optimize therapy, which should be further validated in multicentre studies.

B-Lines in Assessment of Pulmonary Hypertension in Patients With Interstitial Lung Diseases: Feasibility of Transthoracic Lung Sonographic Signs

OBJECTIVES

This study was conducted to evaluate the value of sonographic B-lines (previously called "comet tail artifacts") in assessment of pulmonary hypertension in patients with interstitial lung diseases.

METHODS

One hundred thirty-four patients with clinically diagnosed interstitial lung diseases complicated by pulmonary hypertension underwent transthoracic lung sonography and Doppler echocardiography for assessment of the presence of B-lines, the distance between them, and the pulmonary artery (PA) systolic pressure. A correlation analysis and a receiver operating characteristic curve analysis were performed.

RESULTS

All patients had diffuse bilateral B-lines. The maximum number of B-lines seen in any positive zone (not a summation) was significantly correlated with the severity of PA systolic pressure (r= 0.812; P< .0001), and a linear regression equation could be demonstrated: that is, y = 6.06 x + 17.57, where x and y represent the number of B-lines and PA systolic pressure, respectively. A cutoff of more than 4 B-lines seen in any positive zone had 89.5% sensitivity, 85.0% specificity, and 87.2% accuracy in predicting elevated PA pressure (>30 mm Hg).

CONCLUSIONS

The number of B-lines is useful in assessment of pulmonary hypertension, especially when tricuspid regurgitation and pulmonary valve regurgitation do not exist or cannot be satisfactorily measured by Doppler echocardiography.

How I do it: lung ultrasound

In the last 15 years, a new imaging application of sonography has emerged in the clinical arena: lung ultrasound (LUS). From its traditional assessment of pleural effusions and masses, LUS has moved towards the revolutionary approach of imaging the pulmonary parenchyma, mainly as a point-of-care technique. Although limited by the presence of air, LUS has proved to be useful in the evaluation of many different acute and chronic conditions, from cardiogenic pulmonary edema to acute lung injury, from pneumothorax to pneumonia, from interstitial lung disease to pulmonary infarctions and contusions. It is especially valuable since it is a relatively easy-to-learn application of ultrasound, less technically demanding than other sonographic examinations. It is quick to perform, portable, repeatable, non-ionizing, independent from specific acoustic windows, and therefore suitable for a meaningful evaluation in many different settings, both inpatient and outpatient, in both acute and chronic conditions.In the next few years, point-of-care LUS is likely to become increasingly important in many different clinical settings, from the emergency department to the intensive care unit, from cardiology to pulmonology and nephrology wards.