Ventilator-associated pneumonia in neonates: the role of point of care lung ultrasound

The spectrum of pneumonia among intubated neonates in the neonatal intensive care unit

We review the pathophysiology, epidemiology, diagnosis, treatment, and prevention of ventilator-associated pneumonia (VAP) in neonates. VAP has been studied primarily in adult ICU patients, although there has been more focus on pediatric and neonatal VAP (neo-VAP) in the last decade. The definition as well as diagnosis of VAP in neonates remains a challenge to date. The neonatal intensivist needs to be familiar with the current diagnostic tools and prevention strategies available to treat and reduce VAP to reduce neonatal morbidity and the emergence of antibiotic resistance. This review also highlights preventive strategies and old and emerging treatments available.

Lung Ultrasound and Ultrasound Score: A Useful Tool in Neonatal Intensive Care Units for the Diagnosis and Therapeutic Management of Newborns With Respiratory Pathology

Pulmonary ultrasound has become a fundamental tool for the early detection and management of major neonatal lung diseases in neonatal intensive care units (NICUs). The advantages of this imaging investigation include its rapid execution and information acquisition, non-invasive nature, early diagnosis establishment, dynamic monitoring, and usefulness in therapeutic management. Regarding therapeutic management, the lung ultrasound (LUS) score is used as a basic tool for indicating surfactant administration. Performing and interpreting pulmonary ultrasounds requires an experienced clinician capable of recognizing anatomical structures, understanding the limitations of the technique, and correlating the obtained data with the patient's clinical picture. A series of diagnostic characteristics of pulmonary ultrasonography for neonatal lung pathologies have been described, making pulmonary ultrasound a useful tool in establishing differential diagnoses. This study evaluates the effectiveness of ultrasonography in determining the severity of lung pathologies in newborns and its impact on therapeutic decision-making, including surfactant administration and continuous positive airway pressure (CPAP) support. Newborns admitted to the NICU with various respiratory conditions underwent LUS scoring. The study analyzed the relationship between LUS scoring and the severity of conditions such as pneumonia, respiratory distress syndrome, meconium aspiration syndrome, transient tachypnea of the newborn, and pneumothorax. The correlation between LUS scoring, surfactant administration, and CPAP requirements was also examined.

Variations and National Perspectives on Evaluation and Management of Ventilator-Associated Pneumonia in Neonatal Intensive Care Units: An In-Depth Survey Analysis

Introduction Infants in the neonatal intensive care unit (NICU) are vulnerable to ventilator-associated pneumonia (VAP), which increases their morbidity and mortality. There is a significant overlap of clinical features of neonatal VAP with other pulmonary pathologies, particularly in preterm infants, which can make the definitive diagnosis and management of VAP challenging. Objective Our study surveyed NICU providers across the United States to understand the perspectives and variations in neonatal VAP diagnostic and management practices. Methods The REDCap survey was distributed to the actively practicing members of the Section on Neonatal-Perinatal Medicine (SoNPM) of the American Academy of Pediatrics (AAP). We used descriptive statistics to analyze the data from the respondents. Results Of 254 respondents, the majority (86.6%, 220) were neonatologists and had a relatively even geographical distribution. Most (75.9%, 193) stated that they would perform a gram stain and respiratory culture as part of a sepsis workup irrespective of the patient's duration on invasive mechanical ventilation (IMV); 224 (88.2%) of providers preferred the endotracheal aspiration (ETA) technique to collect specimens. In cases where a positive respiratory culture was present, VAP (52.4%, 133) was the predominantly assigned diagnosis, followed by pneumonia (27.2%, 69) and ventilator-associated tracheitis (VAT) (9.8%, 25). Respondents reported a prescription of intravenous gentamicin (70%, 178) and vancomycin (41%, 105) as the initial empiric antibiotic drugs, pending final respiratory culture results. Most respondents (55.5%, 141) opted for seven days of antibiotics duration to treat VAP. The reported intra-departmental variation among colleagues in acquiring respiratory cultures and prescribing antibiotics for VAP was 48.8% (124) and 37.4% (95), respectively, with slightly more than half (53.5%, 136) of providers reporting having VAP prevention guidelines in their units. Conclusion The survey study revealed inconsistencies in the investigation, diagnostic nomenclature, choice of antibiotic, and treatment duration for neonatal VAP. Consequently, there is a pressing need for further research to establish a clear definition and evidence-based criteria for VAP.

Incidence, Risk Factors, Short-term Outcomes, and Microbiome of Ventilator-associated Pneumonia in Very-low-birth-weight Infants: Experience at a Single Level III Neonatal Intensive Care Unit

BACKGROUND

Ventilator-associated pneumonia (VAP) is a common hospital-acquired infection in neonates on invasive mechanical ventilation, resulting in high morbidity and mortality. The objective of this study is to determine the incidence, risk factors, short-term outcomes and microbiome associated with VAP in very-low-birth-weight (VLBW) infants born at <32 weeks of gestational age (GA).

METHODS

Retrospective study of intubated VLBW infants born at <32 weeks of GA admitted to the Los Angeles General Medical Center neonatal intensive care unit from July 2015 to July 2021 who had routine tracheal aspirate cultures obtained. Neonates were retrospectively classified into 3 groups, confirmed VAP, suspected VAP and no VAP, for comparison of risk factors, outcomes and airway microbial colonization.

RESULTS

Eighty-seven infants met inclusion criteria with a mean GA of 26.1 ± 1 weeks and mean birth weight of 812 ± 281 g. The incidence of VAP was 7.8 per 1000 ventilator days, and the most common causative organisms were Gram-positive organisms (39%), predominantly coagulase-negative Staphylococcus. Duration of postnatal dexamethasone exposure predicted VAP compared to no VAP (coefficient, 0.31; 95% CI 0.03-0.59; P = 0.03) after adjusting for duration of intubation, surfactant use and antenatal steroid exposure. Infants with VAP had higher rate of grade 2/3 bronchopulmonary dysplasia (P = 0.03) and longer hospital stay (P = 0.04).

CONCLUSIONS

VAP occurs at a high rate in VLBW infants who are exposed to prolonged dexamethasone use. It is predominantly caused by Gram-positive organisms.

Diagnostic Accuracy of Lung Ultrasound in Neonatal Diseases: A Systematized Review

Background: Respiratory problems are frequent in newborns, and are mainly studied with chest X-rays, whereas CT scans are usually needed for the evaluation of rare malformations and diseases. Lung ultrasound (LUS] has been proposed as an alternative method of diagnosing a variety of respiratory conditions. In recent years, there has been a rapid increase in LUS studies, thanks to the ability of LUS to rapidly exclude complications and significantly reduce radiation exposure in this fragile population. We aimed to summarize the current knowledge about LUS. Methods: A literature search was conducted on the Medline and Cochrane databases using appropriate terms. The inclusion criteria were: English language and human species. Exclusion criteria were: non-English language, animal species, case reports, case series, non-systematic reviews, and editorials. Results: The search returned 360 results. No Cochrane reviews were found. Titles and abstracts were screened, and 37 were finally considered. Studies concerning the use of lung ultrasound for the following conditions were presented: neonatal respiratory distress syndrome, transient tachypnea of the newborn, pneumothorax, pulmonary hemorrhage, pneumonia, bronchopulmonary dysplasia, and prediction of extubation success. Conclusions: We discussed the utility of LUS for the diagnosis and treatment of neonatal diseases according to the most recent literature.

Neonatal point-of-care lung ultrasound: what should be known and done out of the NICU?

Lung ultrasound is rapidly becoming a useful tool in the care of neonates: its ease of use, reproducibility, low cost, and negligible side effects make it a very suitable tool for the respiratory care of all neonates. This technique has been extensively studied by different approaches in neonatal intensive care unit (NICU), both for diagnostic and prognostic aims and to guide respiratory treatments. However, many neonates are being born in level I/II hospitals without NICU facilities so all pediatricians, not just neonatal intensivists, should be aware of its potential. This is made possible by the increasing access to ultrasound machines in a modern hospital setting. In this review, we describe the ultrasonographic characteristics of the normal neonatal lung. We also discuss the ultrasound features of main neonatal respiratory diseases: transient tachypnea of the neonate (TTN), respiratory distress syndrome (RDS), meconium aspiration syndrome (MAS), pneumothorax (PNX), pleural effusion (PE), or pneumonia. Finally, we mention two functional approaches to lung ultrasound: 1. The use of lung ultrasound in level I delivery centers as a mean to assess the severity of neonatal respiratory distress and request a transport to a higher degree structure in a timely fashion. 2. The prognostic accuracy of lung ultrasound for early and targeted surfactant replacement.

CONCLUSION

 LU is still a useful tool in level I/II neonatal units, both for diagnostic and functional issues.

WHAT IS KNOWN

• Neonatal lung ultrasound has been recently introduced in the usual care in many Neonatal Intensive Care Units.

WHAT IS NEW

• It also has many advantages in level I/II neonatal units, both for neonatologist or even pediatricians that treat neonates in those sites.

Point-of-care lung ultrasound in detecting pneumonia: A systematic review

Purpose

Limited evidence exists to assess the sensitivity, specificity, and accuracy of point-of-care lung ultrasound (LUS) across all age groups. This review aimed to investigate the benefits of point-of-care LUS for the early diagnosis of pneumonia compared to traditional chest X-rays (CXR) in a subgroup analysis including pediatric, adult, and geriatric populations.

Material and Methods

This systematic review examined systematic reviews, meta-analyses, and original research from 2017 to 2021, comparing point-of-care LUS and CXR in diagnosing pneumonia among adults, pediatrics and geriatrics. Studies lacking direct comparison or exploring diseases other than pneumonia, case reports, and those examining pneumonia secondary to COVID-19 variants were excluded. The search utilized PubMed, Google Scholar, and Cochrane databases with specific search strings. The study selection, conducted by two independent investigators, demonstrated an agreement by the Kappa index, ensuring reliable article selection. The QUADAS-2 tool assessed the selected studies for quality, highlighting risk of bias and applicability concerns across key domains. Statistical analysis using Stata Version 16 determined pooled sensitivity and specificity via a bivariate model, emphasizing LUS and CXR diagnostic capabilities. Additionally, RevMan 5.4.1 facilitated the calculation of sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV), offering insights into diagnostic accuracy.

Results

The search, conducted across PubMed, Google Scholar, and Cochrane Library databases by two independent investigators, initially identified 1045 articles. Following screening processes, 12 studies comprised a sample size of 2897. LUS demonstrated a likelihood ratio of 5.09, a specificity of 81.91%, and a sensitivity of 92.13% in detecting pneumonia in pediatric, adult, and geriatric patients, with a p-value of 0.0002 and a 95% confidence interval, indicating diagnostic accuracy ranging from 84.07% to 96.29% when compared directly to CXR.

Conclusion

Our review supports that LUS can play a valuable role in detecting pneumonia early with high sensitivity, specificity, and diagnostic accuracy across diverse patient demographics, including pediatric, adult, and geriatric populations. Since it overcomes most of the limitations of CXR and other diagnostic modalities, it can be utilized as a diagnostic tool for pneumonia for all age groups as it is a safe, readily available, and cost-effective modality that can be utilized in an emergency department, intensive care units, wards, and clinics by trained respiratory care professionals.

No Critical Ultrasound, No Life: The Value of Point-of Care Critical Ultrasound in the Rescue of Critically Ill Infants

Point-of-care critical ultrasound (POC-CUS) screening plays an increasingly important role in the treatment of critically ill infants. Without POC-CUS, the lives of many infants would not be saved in time and correctly. A premature infant with systemic multiple organ system dysfunction caused by fungal sepsis was treated and nursed under the guidance of POC-CUS monitoring, and the infant was ultimately cured. This premature infant had systemic multiple organ system dysfunction and disseminated intravascular coagulation (DIC) caused by fungal sepsis. In the hypercoagulable state of early-stage DIC, cardiac thrombosis could be found using ultrasound screening. For this case, right renal artery thrombosis was found via renal artery Doppler ultrasound examination. Due to the severity of this disease, ultrasound-guided peripherally inserted central catheter (PICC) insertion and ultrasound checks of the PICC tip's position were performed, which ensured the success of this one-time catheterization and shortened the catheterization time. Lung ultrasound is used for the diagnosis and differential diagnosis of pulmonary diseases, and to guide the application of mechanical ventilation. Because the abdominal circumference of the patient's markedly enlarged abdominal circumference, bloody stool, and absence of bowel sounds, abdominal ultrasonography was performed, which revealed a markedly enlarged liver, significant peritoneal effusion, and necrotizing enterocolitis. Guided by POC-CUS monitoring, we had the opportunity to implement timely and effective treatment that ultimately saved this critically ill patient's life. The successful treatment of this newborn infant fully reflects the importance of carrying out POC-CUS screening.

Bile Acids Pneumonia: A Respiratory Distress Syndrome in Early-Term Neonates

Intrahepatic cholestasis of pregnancy (ICP) complicates among 0.2-2% of pregnancies and has been associated with adverse perinatal outcomes, including sudden stillbirth, meconium strained fluid, preterm birth, perinatal asphyxia, and transient tachypnea of the newborn. The diagnosis of "bile acids pneumonia" was previously proposed and a causative role of bile acids (BA) was supposed with a possible mechanism of action including surfactant dysfunction, inflammation, and chemical pneumonia. In the last few years, the role of lung ultrasound (LUS) in the diagnosis and management of neonatal respiratory distress syndrome has grown, and LUS scores have been introduced in the literature, as an effective predictor of the need for surfactant treatment among neonates with respiratory distress syndrome. We present four cases of infants born from pregnancies complicated by ICP, who developed respiratory distress syndrome early after birth. Lung ultrasound showed the same pattern for all infants, corresponding to a homogeneous alveolar-interstitial syndrome characterized by a diffuse coalescing B-line pattern (white lung). All infants evaluated require non-invasive respiratory support and in three cases surfactant administration, despite the near-term gestational age, with rapid improvement of respiratory disease and a good clinical outcome.

Imaging of bronchopulmonary dysplasia

Bronchopulmonary dysplasia (BPD) is a multifactorial disease with many associated co-morbidities, responsible for most cases of chronic lung disease in childhood. The use of imaging exams is pivotal for the clinical care of BPD and the identification of candidates for experimental therapies and a closer follow-up. Imaging is also useful to improve communication with the family and objectively evaluate the clinical evolution of the patient's disease. BPD imaging has been classically performed using only chest X-rays, but several modern techniques are currently available, such as lung ultrasound, thoracic tomography, magnetic resonance imaging and electrical impedance tomography. These techniques are more accurate and provide clinically meaningful information. We reviewed the most recent evidence published in the last five years regarding these techniques and analyzed their advantages and disadvantages.

Pulmonary Sonography - Neonatal Diagnosis Part 2

A healthy, air-filled lung can only be visualized by its artifacts, and pathologies of the lung are revealed by changes in these artifacts. Because ultrasound artifacts are predominantly used in pulmonary sonography to assess pathologic processes, the variability of sonographically imageable phenomena is limited. For this reason, different pulmonary diseases may present very similarly in ultrasound. Therefore, a correct interpretation of the findings is only possible in the clinical context, taking into account the age-dependent differential diagnoses.The particular relevance of lung ultrasound in the treatment of neonatal patients results from a close correlation between the extent of sonographically-depictable pathologies and parameters of respiratory insufficiency. This suggests a direct correlation between ultrasound findings and the severity of lung injury. Lung ultrasound thus represents a unique, ubiquitously available, bedside, serial method for monitoring the pulmonary status.

Lung Ultrasound Monitoring of Legionella Ventilator-Associated Pneumonia in an Extremely Low-Birth-Weight Infant

Ventilator-associated pneumonia (VAP) is a common complication of different severe lung diseases that need to be treated with mechanical ventilation in newborn infants. However, VAP due to Legionella pneumophila infection is rarely reported in the literature, especially in extremely low-birth-weight (ELBW) infants. Lung ultrasound (LUS) has been used in the diagnosis of neonatal pneumonia, but there is no literature on the ultrasound characteristics of Legionella-VAP in ELBW infants. This paper introduced the typical LUS findings of Legionella-VAP in ELBW infants, which mainly includes severe and large-area lung consolidation and atelectasis in the bilateral lungs; whether there is blood supply in the consolidated area has an important reference value for predicting the prognosis. In addition, the treatment and management experience were also introduced together, thereby helping us to deepen the understanding of the disease and avoid missed diagnoses.

Lung Ultrasound to Diagnose Pneumonia in Neonates with Fungal Infection

With the improvement in survival rates of low-birthweight and very premature infants, neonatal fungal infection, especially fungal pneumonia, is becoming more and more common, but the diagnosis is always challenging. Recently, lung ultrasound (LUS) has been used to diagnose pneumonia in newborn infants, but not fungal pneumonia. This paper summarizes the ultrasonographic features of seven cases of neonatal fungal pneumonia, such as lung consolidation with air bronchograms, shred signs, lung pulse, pleural line abnormalities, and different kinds of B-lines. It was confirmed that LUS plays an important role in the diagnosis of fungal pneumonia in newborn infants.

The Role of Lung Ultrasound Monitoring in Early Detection of Ventilator-Associated Pneumonia in COVID-19 Patients: A Retrospective Observational Study

Specific lung ultrasound signs combined with clinical parameters allow for early diagnosis of ventilator-associated pneumonia in the general ICU population. This retrospective cohort study aimed to determine the accuracy of lung ultrasound monitoring for ventilator-associated pneumonia diagnosis in COVID-19 patients. Clinical (i.e., clinical pulmonary infection score) and ultrasound (i.e., presence of consolidation and a dynamic linear−arborescent air bronchogram, lung ultrasound score, ventilator-associated lung ultrasound score) data were collected on the day of the microbiological sample (pneumonia-day) and 48 h before (baseline) on 55 bronchoalveolar lavages of 33 mechanically-ventilated COVID-19 patients who were monitored daily with lung ultrasounds. A total of 26 samples in 23 patients were positive for ventilator-associated pneumonia (pneumonia cases). The onset of a dynamic linear−arborescent air bronchogram was 100% specific for ventilator-associated pneumonia. The ventilator-associated lung ultrasound score was higher in pneumonia-cases (2.5 (IQR 1.0 to 4.0) vs. 1.0 (IQR 1.0 to 1.0); p < 0.001); the lung ultrasound score increased from baseline in pneumonia-cases only (3.5 (IQR 2.0 to 6.0) vs. −1.0 (IQR −2.0 to 1.0); p = 0.0001). The area under the curve for clinical parameters, ventilator-associated pneumonia lung ultrasound score, and lung ultrasound score variations were 0.472, 0.716, and 0.800, respectively. A newly appeared dynamic linear−arborescent air bronchogram is highly specific for ventilator-associated pneumonia in COVID-19 patients. A high ventilator-associated pneumonia lung ultrasound score (or an increase in the lung ultrasound score) orients to ventilator-associated pneumonia.

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).

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.

The association between clinical and biochemical characteristics of late-onset sepsis and bronchopulmonary dysplasia in preterm infants

Studies in preterm infants have shown an association between late-onset sepsis (LOS) and the development of bronchopulmonary dysplasia (BPD). It is unknown whether clinical or biochemical characteristics during sepsis modulate the risk for BPD. This single-center retrospective cohort study included all patients with a gestational age < 30 weeks, born between 2009 and 2015, in whom empiric antimicrobial treatment was initiated > 72 h after birth and continued for at least 5 days, independent on microbiological results. The association between clinical and biochemical characteristics of LOS and the development of BPD in survivors were assessed with multivariate logistic regression analysis adjusted for early-onset sepsis, small for gestational age, and gestational age. Of the 756 admitted infants, 256 infants (mean GA: 27.0 weeks; birthweight: 924 grams) had at least one LOS episode, of whom 79 (30.9%) developed BPD. Analyses showed that only the need for and duration of mechanical ventilation during LOS were independently associated with an increased risk for BPD (adjusted OR 2.62, 95% CI 1.38, 4.96, p value 0.003, and OR 1.004, 95% CI 1.00, 1.007, p value 0.045, respectively).Conclusion: During a LOS, the need for and duration of mechanical ventilation are independently associated with the risk of developing BPD in preterm infants. What is Known: • Premature infants diagnosed with a late-onset sepsis are at higher risk of developing bronchopulmonary dysplasia • This association is mainly shown in infants with a positive blood culture What is New: • This study investigates the clinical and biochemical characteristics of late-onset sepsis and the development of bronchopulmonary dysplasia • The need for mechanical ventilation and duration of mechanical ventilation during late-onset sepsis are associated with an increased risk of developing bronchopulmonary dysplasia.

Early surfactant replacement guided by lung ultrasound in preterm newborns with RDS: the ULTRASURF randomised controlled trial

This study aimed to investigate whether using lung ultrasound (LUS) scores in premature newborns with respiratory distress syndrome (RDS) allows for earlier surfactant therapy (within the first 3 h of life) than using FiO₂ criteria. This was a randomised, non-blinded clinical trial conducted in a neonatal intensive care unit. The inclusion criteria were newborns with a gestational age of ≤ 32 weeks and RDS. Patients meeting the inclusion criteria were randomly assigned to two groups: the ultrasound group, administered surfactant based on LUS score and/or FiO₂ threshold, and the control group, guided by FiO₂ only. Fifty-six patients were included. The ultrasound group received surfactant earlier (1 h of life vs. 6 h, p < 0.001), with lower FiO₂ (25% vs. 30%, p = 0.016) and lower CO₂ (48 vs. 54, p = 0.011). After surfactant treatment, newborns in the ultrasound group presented a greater SpO₂ (p = 0.001) and SpO₂/FiO₂ ratio (p = 0.012).Conclusions: LUS score allowed an earlier surfactant therapy, reduced oxygen exposure early in life and a better oxygenation after the treatment. This early surfactant replacement may lead to reduced oxygen exposure. What is Known: • Lung ultrasound scores predict the need for surfactant therapy in premature newborns. What is New: • This study shows that using lung ultrasound scores improves the timeliness of surfactant replacement compared with using FiO₂ alone.