Functional Echocardiography in the Neonatal Intensive Care Unit

Narrative Review on Echocardiographic Evaluation of Patent Ductus Arteriosus in Preterm Infants

Persistent Patent Ductus Arteriosus (PDA) is prevalent among extremely preterm infants, with its occurrence inversely related to gestational age. A persistent PDA correlates with increased mortality and morbidities such as intraventricular hemorrhage, pulmonary hemorrhage, chronic lung disease, bronchopulmonary dysplasia, and necrotizing enterocolitis as observed clinically. Conversely, numerous randomized controlled trials have failed to demonstrate significant benefits from PDA treatment. One contributing factor to these conflicting findings is that PDA affects each individual differently depending on the cardiovascular decompensation and its hemodynamic impact. PDA management should be based on the hemodynamic significance, rather than just the presence or size of PDA. This comprehensive narrative review paper describes echocardiographic parameters that allow a better understanding of the hemodynamic impact of PDA. A newer modality, like lung ultrasound, is also described here as an adjunct to assess the PDA impact on the lungs from pulmonary overcirculation.

Targeted Neonatal Echocardiography Performed by Nurse Practitioners in the NICU: Attitudes and Perceptions of the Healthcare Team

BACKGROUND

Targeted neonatal echocardiography (TNE) and hemodynamic consultation have typically been performed by physicians. The Stollery Children's Hospital neonatal intensive care unit (NICU) expanded their TNE training program to include neonatal nurse practitioners (NNPs), the first in North America.

PURPOSE

This study examines the thoughts and perceptions of clinicians about the incorporation of NNPs providing TNE and hemodynamic consultation and investigates key facilitators and challenges for consideration when planning future training, expansion of service in Edmonton, or beyond.

METHODS

In this descriptive study using qualitative methodology, purposive sampling was used to invite NICU clinicians to participate. Using a semistructured topic guide, a focus group and 2 individual interviews were conducted.

RESULTS

Participants were supportive of NNPs. Advantages included increased access to service, acquisition and retention of skills, provision of patient-centered care, and leveraged interpersonal relationships in the decision-making process. Key aspects of program expansion included climate and culture of the NICU, presence of adequate patient volume, and resources to support training.

IMPLICATIONS FOR PRACTICE AND RESEARCH

Support across disciplines and the collaborative working nature of the NICU are key factors in the success of the program's development and implementation. Benefits of having NNPs on the TNE team were clearly expressed. Benefits to the health system included rapid access to hemodynamic information allowing for care based on specific pathophysiology and additional local capacity to perform TNE and reducing demand on other trained providers. Additional research could consider parental views of NNPs performing TNE and hemodynamic consultation as well as the accuracy of diagnosis between the NNPs and physician group.

Educational Impact of Targeted Neonatal Echocardiography and Hemodynamics Programs on Neonatal-Perinatal Medicine Fellows

OBJECTIVE

Targeted neonatal echocardiography (TNE) is a real-time cardiac imaging modality used by a hemodynamics program to aid in diagnosis, treatment, and monitoring of neonatal cardiovascular illness. This study aimed to describe trainees' perspectives on existing hemodynamics education and perceived impacts of TNE and hemodynamics services on their education.

STUDY DESIGN

This was a mixed quantitative and qualitative study that surveyed neonatal-perinatal medicine (NPM) fellow trainees in Canada and the United States, at programs both with and without a hemodynamics service.

RESULTS

Ninety-two fellows responded to the survey, of whom 24 (26%) were enrolled in a program with an active hemodynamics service, 64 (70%) were training at a program without a hemodynamics service, and 4 (4%) were unsure. Trainees at centers with a hemodynamics service were more satisfied with their cardiovascular physiology education (91 vs. 69%, p = 0.040). Twenty-five percent of all trainees felt they do not have sufficient hemodynamics training to prepare them for independent practice. Areas of knowledge gaps were identified. Bedside teaching combined with didactic teaching was identified as useful means of teaching.

CONCLUSION

Most trainees believed that TNE and a hemodynamics service are valuable educational assets. Thoughtful curriculum design for real-time and consolidation learning, with specific emphasis on content gaps, should be considered.

KEY POINTS

· NPM Fellows perceive TNE & Neonatal Hemodynamics service as a valuable educational opportunity.. · Incorporation of TNE/Hemodynamics teaching into NPM curriculum can enrich trainee experience.. · Combining bedside and classroom teaching is key to successful cardiovascular training..

Trends in Procedures in the Neonatal Intensive Care Unit

OBJECTIVE

The aim of the study is to identify the rates and trends of various procedures performed on newborns.

STUDY DESIGN

The Healthcare Cost and Utilization Project (HCUP) database for the years 2002 to 2015 was queried for the number of livebirths, and various procedures using International Classification of Diseases, Ninth Revision (ICD-9) codes. These were adjusted to the rate of livebirths in each particular year. A hypothetical high-volume hospital based on data from the last 5 years was used to estimate the frequency of each procedure.

RESULTS

Over the study period, there was a decline in the rates of exchange transfusions and placement of arterial catheters. There was an increase in the rates of thoracentesis, abdominal paracentesis, placement of umbilical venous catheter (UVC) lines, and central lines with ultrasound or fluoroscopic guidance. No change was observed in the rates of unguided central lines, pericardiocentesis, bladder aspiration, intubations, and LP. Intubations were the most performed procedures. Placement of UVC, central venous lines (including PICCs), arterial catheters, and LP were relatively common, whereas others were rare such as pericardiocentesis and paracentesis.

CONCLUSION

Some potentially lifesaving procedures are extremely rare or decreasing in incidence. There has also been an increase in utilization of fluoroscopic/ultrasound guidance for the placement of central venous catheters.

KEY POINTS

· Advances in neonatal care have impacted the number of procedures performed in the NICU.. · It is unclear whether invasive procedures occur at rates sufficient for adequate training and maintenance of skills.. · Understanding the NICU procedural trends is important in designing simulation and competency-based medical education programs..

Impact of Targeted Neonatal Echocardiography on Patent Ductus Arteriosus Management in a Canadian Tertiary Care Neonatal Unit: A Retrospective Cohort Study

OBJECTIVE

Comprehensive assessment of hemodynamic significance of a patent ductus arteriosus (PDA) is a common indication to perform targeted neonatal echocardiography (TNE). Impact of implementation of such an assessment on PDA management decisions remains to be reported. The objective of this study is to compare PDA-related hemodynamic information and PDA treatment decisions before and after introduction of TNE service.

STUDY DESIGN

This was a retrospective cohort study at a tertiary level neonatal intensive care unit in Southwestern Ontario. We investigated two time periods: Epoch-1 (non-TNE 2013-2016) versus Epoch-2 (TNE 2018-2021). We included neonates < 32 weeks with PDA. Data on baseline clinical characteristics, PDA-related echocardiographic parameters, PDA treatment details, and relevant long-term outcomes were collected. Primary outcome was defined as PDA treatment rates and need for multiple courses. Secondary outcomes included availability of PDA hemodynamic data and neonatal mortality/morbidity (PDA-related) RESULTS:  A total of 275 neonates were included. A total of 162 were assessed by conventional echocardiography in Epoch-1, whereas 113 were assessed by TNE in Epoch-2. Baseline clinical characteristics were similar. Epoch-2 had more echocardiographic assessments per patient of 2.7 (±1.8) versus 1.9 (± 1.3), p < 0.001 in Epoch1. The mean postnatal age at first echocardiographic assessment was higher in Epoch-2 (12.7 days [ ± 14.6]) than in Epoch-1 (7.9 days [ ± 10.4]), p < 0.001. Comprehensive hemodynamic assessment of PDA-related echocardiographic parameters such as PDA size, shunt pattern, effect on systemic circulation, and pulmonary circulation were higher in Epoch-2. Overall, PDA treatment rates were comparable in the two time periods. The use of multiple courses of treatment was higher in Epoch-1 than in Epoch-2 (47.8 vs. 31.7%, p = 0.047). In Epoch-1, neonates received PDA treatment earlier than in Epoch-2.

CONCLUSION

With the implementation of the TNE service, increased echocardiographic evaluations per patient were completed with availability of more comprehensive hemodynamic information about PDA. PDA treatment rates were similar in the two epochs, but need for multiple courses were less in TNE era.

KEY POINTS

· TNE allows comprehensive hemodynamic assessment of PDA.. · Implementation of dedicated TNE service led to increased use of echocardiography to assess PDA.. · Standardized hemodynamic assessment of PDA may allow improved individualization of treatment need..

Echocardiography in the neonatal unit: current status and future prospects

INTRODUCTION

Traditionally echocardiography was used by pediatric cardiologists to diagnose congenital heart defects in neonates. Formalized neonatal hemodynamic fellowships have been established where neonatologists acquire advanced echocardiographic skills to gain anatomical, physiological, and hemodynamic information in real time and utilize this information in making a timely and accurate physiology-based clinical decision.

AREA COVERED

Differences between a comprehensive formal structural echocardiography, neonatologist performed targeted echocardiography and limited assessment on point-of-care-ultrasonography for specific indications have been covered. This article is focused at providing a comprehensive review of the status of echocardiography in the neonatal units, recent advancements and its future prospects in the neonatal intensive care units.

EXPERT OPINION

Comprehensive guidelines providing the scope of practice, a framework for training, and robust clinical governance process for the neonatologist performed targeted echocardiography have been established. In the last decade, echocardiography has emerged as essential vital bedside diagnostic tool in providing high-quality care to the sick infants in the neonatal units, and it has proved to improve the outcomes in neonates. It is now being considered as a modern hemodynamic monitoring tool. Advances in technology, machine learning, and application of artificial intelligence in applications of echocardiography seem promising adjunct tools for rapid assessment in emergency situations.

Implementing a successful targeted neonatal echocardiography service and a training program: The ten stages of change

Implementing any new service or program in the health care system is not always straightforward; a multi-stage implementation process is required most of the time. With the advancements in neonatal care and increased survival rates, there has been an increased need for ongoing assessment of hemodynamic stability. At the Children's Hospital of Eastern Ontario and the Ottawa Hospital Neonatal Intensive Care Units (NICUs), University of Ottawa, Canada, Targeted Neonatal Echocardiography service (TnEcho) was successfully established and has led to improvement in the hemodynamic evaluation and decision making in neonatal intensive care. In this article, we describe our experience establishing this program and the process of ensuring its success. This review article highlights the ten steps taken by multiple stakeholders to achieve this goal; this may help other centres implement a similar program.

Essentials of Neonatal-Perinatal Medicine fellowship: part 2 - clinical education and experience

This is the second article in a seven-part series in the Journal of Perinatology that aims to critically examine the current state of Neonatal-Perinatal Medicine (NPM) fellowship training from the structure and administration of a program, to the clinical and scholarly requirements, and finally to the innovations and future careers awaiting successful graduates. This article focuses on the current clinical requirements; recent changes to the clinical environment and their effect on learning; and additional challenges and opportunities in clinical education.

Increased N-terminal Pro-B-Type Natriuretic Peptide during Extracorporeal Life Support Is Associated with Poor Outcome in Neonates with Congenital Diaphragmatic Hernia

OBJECTIVES

To evaluate the prognostic information derived from the daily measurements of N-terminal pro-B-type natriuretic peptide (proBNP) in neonates with congenital diaphragmatic hernia undergoing extracorporeal life support (ECLS).

STUDY DESIGN

Plasma proBNP was prospectively measured daily during the first week of ECLS using an electrochemiluminescence immunoassay. Patients (n = 63) were allocated according to outcome: survivors (group 1, n = 35); nonsurvivors with successful weaning (defined as survival for >12 hours after ECLS discontinuation) (group 2, n = 16); nonsurvivors with unsuccessful weaning (group 3, n = 12). ProBNP kinetics were compared using Kruskal-Wallis testing and correlated with pulmonary hypertension and cardiac dysfunction on echocardiography using the Spearman correlation coefficient.

RESULTS

Infants in group 3 presented significantly higher proBNP values from day 3 to day 6 compared with group 1 and 2. Overall mortality among patients with the highest proBNP values on day 1 was 30.6% compared with 63% in those patients with at least 1 higher value on day 2 to day 7. In patients with a late increase (day 4 to day 7) in proBNP the mortality was 70%, compared with 32.6% in those with proBNP below the value on day 1. Weaning failure was 35% in patients with a late increase and 11.6% in those without a late increase. ProBNP correlated significantly with pulmonary hypertension and cardiac dysfunction before and during ECLS.

CONCLUSIONS

Absolute proBNP values are associated with weaning failure but not overall mortality in neonates with congenital diaphragmatic hernia undergoing ECLS. Echocardiographic findings correlate well with proBNP values.

Predictive Tool for Closure of Ductus Arteriosus with Pharmacologic or Surgical Treatment in Preterm Infants

To construct a model with the indices obtained by echocardiography to predict whether patent ductus arteriosus (PDA) was required to be treated with pharmacologic treatment or surgical ligation, we performed a prospective observational study, including all neonates with gestational age ≤ 30 weeks and assessed the hemodynamics of PDA by serial daily echocardiography examination at postnatal age of 0-12 h, 24 h, 48 h, and 72 h, respectively. The infants were classified in two groups based on whether they were treated with non-steroidal anti-inflammatory drugs (NSAIDs) and/or surgical ligation to close the PDA from the second week after birth. We compared the echocardiographic indices between the two groups and utilized the indices to construct a model to predict which premature infants' PDA requires intervention. The results showed that a total of forty-two preterm infants were enrolled in the study. 15 (35.7%) preterms were in the intervention group and 27 (64.3%) preterms were in the non-intervention group. Compared with the non-intervention group, the intervention group had a higher proportion of left ventricular volume overload and systemic shunt effect. In addition, the combined indicators of PDA size/weight > 3.2 mm/kg and LA/Ao > 1.4 at postnatal age of 72 h had a highest value to predict whether PDA requires intervention. These findings denoted that serial daily echocardiographic assessment can be useful in predicting whether a PDA will be closed with NSAIDs and/or surgical ligation in preterm infants with gestational age ≤ 30 weeks.Trial registration Number: IRB No. 2018-IRB-073. Date: 2018/09/21, retrospectively registered.

Congenital heart disease diagnosed with echocardiogram in newborns with asymptomatic cardiac murmurs: a systematic review

BACKGROUND

More than 50% of newborns with congenital heart disease (CHD) are unrecognized at birth; however, the use of echocardiogram (Echo) for diagnosing CHD in newborns with asymptomatic, non-syndromic cardiac murmurs (ANCM), has not been systematically reviewed yet. We aimed to identify the incidence of CHD diagnosed with Echo and systematically review whether Echo should be recommended in this patient group.

METHODS

The methodology utilized in this systematic review adhered to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses framework. Using the MEDLINE, EMBASE, Web of Science, and Cochrane Library databases, we performed a systematic review of publications reporting CHD diagnosed with Echo in newborns with cardiac murmurs. The quality of the included studies was evaluated using the Study Quality Assessment Tools developed by the National Institutes of Health.

RESULTS

Of the 630 studies screened, six cohort studies, four cross-sectional studies, and two case reports were included in this review. The incidence of cardiac murmurs ranged from 0.6-8.6%. Among the 1928 newborns with ANCM, 719 (37.3%) were diagnosed with Echo as having CHD, and ventricular septal defect was the most common congenital malformation. More than 50% of the newborns showed moderate CHD necessitating outpatient cardiology follow-up, and 2.5% had severe CHD requiring immediate interventions, such as cardiac catheterization and heart surgery.

CONCLUSIONS

In this systematic review, a high incidence of CHD in newborns with ANCM was detected using Echo. This indicates that the use of Echo for diagnosing CHD in healthy newborns with cardiac murmurs could be helpful in earlier detection of CHD, thereby improving clinical outcomes for newborns with severe CHD.

Neonatal functional echocardiography

PURPOSE OF REVIEW

The role of echocardiography has dramatically changed over the past decade and use of functional echocardiography has become increasingly popular among neonatologists and pediatric intensivists in making clinical decisions in sick infants and children. The purpose of this review is to outline the current capabilities and limitations of functional echocardiography, best practices for its clinical application, and evidence for its utility.

RECENT FINDINGS

Functional echocardiography can provide direct assessment of hemodynamics at bedside and can be used as a modern hemodynamic monitoring tool in the neonatal intensive care unit. It is now being regarded as a useful extension to the clinical examination and other monitoring tools in the critically ill infant. The anatomic, physiological, and hemodynamic information functional echocardiography provides can be used in targeting specific interventions and evaluating response to treatment.

SUMMARY

This review article is focused on an overview of the most common applications of functional neonatal echocardiography also called targeted neonatal echocardiography or neonatologist performed echocardiography. It will review assessment of hemodynamics and cardiac function in neonatal hypotension and shock, suspected patent ductus arteriosus, suspected persistent pulmonary hypertension of the newborn with evaluation of pulmonary artery pressure and assessment of pericardial effusion. It will also emphasize the specific requirements for the practice and training of functional neonatal echocardiography.

Echocardiographic Diagnosis and Hemodynamic Evaluation of Patent Ductus Arteriosus in Extremely Low Gestational Age Newborn (ELGAN) Infants

Persistent Patent ductus arteriosus (PDA) is a common finding in extremely low gestational age newborn infants and its prevalence is inversely proportional to the gestational age. The presence of a persistent PDA is associated with increased mortality and several significant morbidities including intraventricular hemorrhage, pulmonary hemorrhage, necrotizing enterocolitis, and chronic lung disease or bronchopulmonary dysplasia. However, treating PDA has not been demonstrated to have beneficial impact on the long term outcomes. Currently there is no consensus on whether to treat the PDA or not, and if treat, when to treat and how to treat. The echocardiography is the investigation of choice to diagnose PDA, estimating the magnitude of shunt volume and assessing its hemodynamic significance, and to exclude/diagnose any associated congenital heart defect before any intervention. Various echocardiographic parameters and staging/scoring systems have been described to help the clincians making the clinical decisions and some of theses scoring systems are quite complex to apply in a busy day to day clinical practice. This concised review paper is focused to help the clinicians in making a clinical decision based upon clincial and echocardiography parameters. Hence, only the parameters which are commonly used and helpful in making the clinical decisions in day to day clincial practice have been described in this paper.

Point of care ultrasound (POCUS) in Canadian neonatal intensive care units (NICUs): where are we?

OBJECTIVES

Despite increased evidence that point-of-care ultrasound (POCUS) has the potential to improve patient care in many clinical areas, the extent of use and training in POCUS in Canadian neonatal intensive care units (NICUs) has not been described in the literature. In this study, we aimed to explore the extent to which POCUS is being used and the need for a formal curriculum with defined POCUS competencies in the field of Neonatal-Perinatal Medicine (NPM).

METHODS

We sent a cross-sectional electronic survey to all NPM program directors and fellows in Canada. All 13 Canadian NPM programs were invited to participate. Data were analyzed using descriptive statistics and qualitative content analysis.

RESULTS

The response rate was 69% (n = 9) from program directors (PDs) and 29% (n = 25) from NPM fellows. Most respondents indicated regular use of POCUS in clinical practice and ready access to a portable ultrasound machine. The most common use for POCUS was targeted assessment of patent ductus arteriosus (PDA) and persistent pulmonary hypertension (PPHN). Only six PDs reported that POCUS skills are taught to trainees in their centers and only two PDs reported that a structured program existed. Barriers to POCUS structured training include a lack of trained personnel as well as insufficient time in the busy NPM curriculum.

CONCLUSION

POCUS is widely used in Canadian NICUs. However, a formal curriculum and assessment of competencies in this area of neonatal clinical care are lacking.