LUCAS (lung ultrasonography in cardiac surgery) score to monitor pulmonary edema after congenital cardiac surgery in children

Lung ultrasound in neonates under cardiac surgery: feasible and predictive

PURPOSE

To determine whether pre- and postoperative follow-up based on lung ultrasound is associated with the respiratory and clinical evolution of patients undergoing cardiac surgery in the neonatal period.

METHODS

Prospective observational unicentric study from December 2020 to October 2023 in a neonatal intensive care unit, a referral center for congenital heart diseases (CHD). Neonates with CHD exposed to heart surgery or percutaneous catheterization in their first 28 days of life were included. LU follow-up was performed before surgery (LUSpre) and on days 1 (LUS_1), 3 (LUS_3), and 7 (LUS_7) afterwards by mean of a dedicated score (LUS) ranging from 0 to 3 points in 8 areas (total score 0-24).

RESULTS

Fifty-five neonates were included. Median gestational age was 39.1 weeks (37.8-40.1), birth weight 3088 g (IQR 2910-3400). Forty-nine received surgery and 6 only percutaneous catheterization. Median LUSpre score was associated with total respiratory support in the first 30 postoperative days (p = 0.034). Median postoperative LUS was significantly higher than LUSpre in the surgery cohort at all time points (p < 0.05). LUS_1 was associated with respiratory and several clinical outcomes: for each point increase in the ultrasound score, the days on invasive mechanical ventilation, the need for any respiratory support within the first 30 postoperative days, and the length of NICU stay increased significantly (p < 0.05). The presence of consolidations in any area in the postoperative lung ultrasounds was associated with worse respiratory outcomes: higher invasive mechanical ventilation duration (6.84 days), longer total respiratory support (6.07 days), and NICU admission (21.61 days). The presence of consolidations in LUS_7 was significantly associated with the occurrence of ipsilateral diaphragmatic paralysis (odds ratio of 10.25 (95% CI 2.05-51.26, p = 0.006).

CONCLUSION

Performance of lung ultrasound follow-up in CHD in the NICU is feasible and predictive of the respiratory evolution of the patient. LUS_1 presented the highest predictive values. The presence of consolidations is associated with a worse respiratory evolution and if they persist for a week after the procedure, it may raise suspicion of ipsilateral diaphragmatic paralysis.

Comparison of different types of ultrasound probes for lung ultrasound in neonates-A prospective randomized comparison study

OBJECTIVE

To determine the effect of different types of probes for lung ultrasound in neonates.

DESIGN

Prospective, blinded, randomized, comparative study between 2020 and 2022.

SETTING

Single-center study at a third level neonatal unit.

PATIENTS

Hemodynamically stable infants with either nasal continuous positive airway pressure, high flow nasal cannula or without respiratory support.

INTERVENTION

Lung ultrasound using either an echo or microconvex probe. As control, the linear probe was used.

MAIN OUTCOME MEASURES

Primary outcome measure was neonatologist performed lung ultrasound (NPLUS) score. Secondary outcome measures were number of B-Lines, thickness of the pleural line and subjective image quality. Furthermore, correlation between NPLUS results and clinical data was assessed.

RESULTS

A total of 1584 video loops from 66 patients, with a mean corrected gestational age of 33.8 weeks (SD 4.23) and weight of 1950g (SD 910), respectively, were analyzed. NPLUS score was estimated lower with the echo- and microconvex probe compared to the linear probe, with a coefficient of -2.95 (p < 0.001) and -1.09 (p = 0.19), respectively. Correlation between the pulse oximetric saturation/fraction of inspired oxygen ratio and NPLUS score was moderately strong and best using the microconvex probe (Spearman's rho = -0.63, p<0.001).

CONCLUSION

Our results not only confirm the current recommendations, but also demonstrate the extent of the varying results when different probes are used. The differences we discovered call for caution in interpreting scores, especially in the context of guiding therapies and communicating prognoses. Finally, the correlation between NPLUS score and clinical parameters contributes to validating the use of this diagnostic tool.

Thoracic Fluid Content in Neonates Presented with Respiratory Distress as a Predictive Tool for Transient Tachypnea of Newborn

INTRODUCTION

Respiratory conditions are the most common reason for admission of newborns to a neonatal care unit. The index of contractility (ICON) can be used to measure the thoracic fluid content (TFC) in neonates which is a significant parameter in cases presented with transient tachypnea of newborn (TTN).

OBJECTIVE

The objective was to compare TFC between newborn infants with TTN compared with other causes of respiratory distress (RD). We tested the hypothesis that TFC would be higher in infants with TTN.

STUDY DESIGN

In total, 105 newborns were enrolled at the delivery room and were categorized into three groups: TTN, other causes of RD, and control, according to physical examination and Chest X-Ray. TFC was measured within the first 6 hours for all infants and at 24 and 48 hours for the first two groups.

RESULTS

Demographic data showed higher male participants and use of antenatal steroid therapy in RD groups. TFC within the first 6 hours was higher in RD groups. However, TFC at 24 hours of ≤24 mL/kg, and TFC drop rate at 24 hours of >12% are statistically significant discriminators of TTN from non-TTN, with sensitivity and specificity of 97.1 and 47.1%, and 60 and 82.4%, respectively (Fig 1 and 2).

CONCLUSION

ICON can be used in conjunction with clinical parameters and CXR as a tool for differentiation between TTN and other causes of RD within the first 24 hours of life by using the cutoff value of TFC at 24 hours and TFC drop rate. This will allow earlier and optimum management of different causes of RD.

KEY POINTS

· Thoracic fluid content. · Neonatal respiratory distress. · Newborn.

Lung ultrasound in the evaluation of pulmonary edema in newborns with critical congenital heart disease

BACKGROUND

Newborns with critical congenital heart disease (CCHD) with increased pulmonary blood flow (PBF) are at high risk for congestive heart failure. In this study, we aimed to evaluate the presence and degree of pulmonary edema in newborns with CCHD using lung ultrasound (LUS) during the perioperative period.

METHODS

Prospective clinical trial, 44 newborn patients with CCHD were evaluated in this prospective clinical trial. LUS was repeatedly performed to determine the course of pulmonary edema during the perioperative period. LUS was performed simultaneously with chest radiography (CXR), which was the main part of patient management. The primary outcome of this study was to identify whether a correlation existed between LUS and CXR findings. The secondary outcomes were to determine the relationship between LUS and the need for respiratory support, diuretic use, vasoactive inotropic score (VIS), and pro-B-type natriuretic peptide (pro-BNP) levels during the perioperative period.

RESULTS

The mean gestational age of the patients was 38.3 ± 1.7 weeks, with a mean birth weight of 3026 ± 432 g. In the preoperative period, both LUS and CXR images were consistent with clinical signs of pulmonary edema. On the first postoperative day, pulmonary edema increased compared to the preoperative period but gradually decreased by the 6th day of surgery (p < 0.05). Positive correlations were observed between the LUS and CXR findings at all study points (p < 0.05). The LUS findings exhibited trends parallel to those of VIS, serum pro-BNP levels, need for respiratory support, and diuretic requirements. As expected, these trends were more pronounced in CCHDs where PBF increased.

CONCLUSION

In CCHD, serial lung ultrasound (LUS) assessments, particularly in cases with increased PBF, can provide valuable guidance for managing patients during the perioperative period.

Point-of-Care-Ultrasound in Pediatrics: A Review and Update

Point-of-Care-Ultrasound (POCUS) has encountered a tremendous expansion in patient care. POCUS has taken a central role during invasive procedures. POCUS has expanded to most subspecialties from adult to pediatric and neonatal health care. POCUS in pediatrics has also become part of specific critical situations such as myocardial function assessment during cardiac arrest, extracorporeal membrane oxygenation deployment and neurological evaluation. In this review we will go over the most important historical aspects of POCUS. We will also review important aspects of POCUS in the intensive care unit, cardiologist evaluation and in the emergency department among others.

Lung ultrasound assessment of pulmonary edema in neonates with chronic lung disease before and after diuretic therapy

INTRODUCTION

Bronchopulmonary dysplasia (BPD) is characterized by lung injury with varying degrees of disrupted alveolarization, vascular remodeling, inflammatory cell proliferation, and pulmonary edema. Diuretics are often used to ameliorate the symptoms or progression of BPD. Our primary objective was to use lung ultrasound (LUS) to determine if diuretics decrease pulmonary edema in infants with BPD. The secondary objective was to assess changes in respiratory support during the first week after initiation of diuretics.

METHODS

Premature infants requiring noninvasive respiratory support and starting diuretic therapy for evolving BPD were compared with a similar group of infants not receiving diuretics (control). For the diuretic group, LUS exams were performed before and on Days 1, 3, and 6 after initiation of treatment. For the control group, LUS was performed at equivalent time points. A composite pulmonary edema severity (PES) score of 0-5 was calculated based on the total number of B-lines in six scanned areas. Respiratory support parameters (FiO₂ , nasal cannula flow, or CPAP) were also recorded.

RESULTS

Infants in the diuretic (n = 28) and control (n = 23) groups were recruited at median corrected gestational ages of 34.2 (33.3-35.9) and 34.0 (33.4-36.3) weeks, respectively (p = 0.82). PES scores, FiO₂ , and respiratory flow support decreased significantly from Days 0 to 6 (p < 0.0001, p = 0.001, and p = 0.01, respectively) in the diuretic group, but not in the control group.

CONCLUSION

Diuretic use is associated with decreased pulmonary edema and improved oxygenation in infants with BPD during the first week of treatment.

Lung Ultrasound versus Chest X-Ray for the Detection of Fluid Overload in Critically Ill Children: A Systematic Review

Fluid overload is a common complication of critical illness, associated with increased morbidity and mortality. Pulmonary fluid status is difficult to evaluate clinically and many clinicians utilize chest X-ray (CXR) to identify fluid overload. Adult data have shown lung ultrasound (LUS) to be a more sensitive modality. Our objective was to determine the performance of LUS for detecting fluid overload, with comparison to CXR, in critically ill children. We conducted a systematic review using multiple electronic databases and included studies from inception to November 15, 2020. The sensitivity and specificity of each test were evaluated. Out of 1,209 studies screened, 4 met eligibility criteria. Overall, CXR is reported to have low sensitivity (44–58%) and moderate specificity (52–94%) to detect fluid overload, while LUS is reported to have high sensitivity (90–100%) and specificity (94–100%). Overall, the quality of evidence was moderate, and the gold standard was different in each study. Our systematic review suggests LUS is more sensitive and specific than CXR to identify pulmonary fluid overload in critically ill children. Considering the clinical burden of fluid overload and the relative ease of obtaining LUS, further evaluation of LUS to diagnose volume overload is warranted.

The Value of Lung Ultrasound Score in Neonatology

Point-of-care lung ultrasound (LUS) is increasingly applied in the neonatal intensive care unit (NICU). Diagnostic applications for LUS in the NICU contain the diagnosis of many common neonatal pulmonary diseases (such as Respiratory distress syndrome, Transient tachypnea of the newborn, Meconium aspiration syndrome, Pneumonia, Pneumothorax, and Pleural effusion) which have been validated. In addition to being employed as a diagnostic tool in the classical sense of the term, recent studies have shown that the number and type of artifacts are associated with lung aeration. Based on this theory, over the last few years, LUS has also been used as a semi-quantitative method or as a "functional" tool. Scores have been proposed to monitor the progress of neonatal lung diseases and to decide whether or not to perform a specific treatment. The semi-quantitative LUS scores (LUSs) have been developed to predict the demand for surfactant therapy, the need of respiratory support and the progress of bronchopulmonary dysplasia. Given their ease of use, accuracy and lack of invasiveness, the use of LUSs is increasing in clinical practice. Therefore, this manuscript will review the application of LUSs in neonatal lung diseases.

Lung Ultrasound in Pediatrics and Neonatology: An Update

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

Lung ultrasound score and diuretics in preterm infants born before 32 weeks: A pilot study

OBJECTIVE

To describe if weekly determined lung ultrasound (LU) scores in preterm infants born before 32 weeks (PTB32W) change with diuretic therapy.

DESIGN

We included infants who received diuretics and compared LU scores according to their evolution on respiratory support (RS) before and after diuretics.

RESULTS

We included 18 PTB32W divided into two groups. Both groups were similar in terms of median gestational age: 26 weeks (interquartile range [IQR]: 25-28) in the responders' group and 27 weeks (IQR: 24-28) in the other. They differed, however, in the median number of days on invasive mechanical ventilation: 27 (IQR: 11-43) versus 76 (IQR: 35-117), p = .03; in addition to the number of infants with moderate-severe bronchopulmonary dysplasia: 3 (33%) versus 8 (89%), p = .025. The responders' group showed lower LU scores 2 days after diuretics, with a median LU score of 6 (IQR: 3-12) versus 14 (IQR: 12-17) in the nonresponders group, p = .03; 1 week after (3 [IQR: 0-10] versus 12 [12-12], p = .04); and 3 weeks after (5 [IQR: 3-6] versus 12 [10-15], p = .01). RS also decreased at the same time: 7 out of 9 (78%) were extubated in the responders' group, and 1 out of 9 (11%) in the nonresponders group, p = .02, and these differences remained throughout the entire follow-up.

CONCLUSIONS

There is a group of PTB32W patients whose LU score improves after diuretics. This change appears only in those patients that can be weaned off from RS, and at the same period of time as the administration of diuretics.