The role of ultrasound in necrotizing enterocolitis

The role of an abbreviated ultrasound in the evaluation of necrotizing enterocolitis

BACKGROUND

Bowel ultrasound is a useful diagnostic tool in the diagnosis and management of necrotizing enterocolitis (NEC) but can be time-consuming and requires technical expertise, particularly for assessing pneumatosis. Previous literature on sonographic evaluation of NEC has focused on a full bowel ultrasound protocol, but the utility of an abbreviated protocol primarily aimed at identifying high-risk sonographic findings without focused bowel assessment has not been well studied.

OBJECTIVE

This study aims to describe the diagnostic accuracy of an abbreviated ultrasound protocol for identifying high-risk NEC findings.

MATERIALS AND METHODS

This is a retrospective, institutional review board-approved study. We identified all abbreviated NEC ultrasounds performed between January 2014 and August 2022 at our institution. Exams were reviewed for the presence of high-risk findings including pneumoperitoneum, fluid collections, and complex free fluid. Clinical outcome was categorized as poor or good depending on if emergent surgical intervention or death related to NEC occurred. The frequency of follow-up NEC ultrasounds was reviewed to determine if new findings affected outcome. Sensitivity, specificity, and positive and negative predictive values were generated to assess the performance of the abbreviated ultrasounds to identify high-risk findings.

RESULTS

A total of 84 abbreviated abdominal ultrasounds were performed on 73 children. Median age at the time of ultrasound was 41 days (interquartile range (IQR) 53 days) and median gestational age was 35 weeks and 3 days (IQR 80 days), and 44/73 (60%) were male. Thirteen ultrasounds had at least one high-risk finding with nine (69%) resulting in a poor outcome, including seven surgical interventions and four deaths. Two patients had surgical intervention and died as a result of necrotizing enterocolitis. Ultrasounds without high-risk findings were not associated with poor clinical outcomes. Sensitivity, specificity, positive predictive value, and negative predictive value of the abbreviated NEC ultrasound were 100% (95% CI 60-100%), 95% (95% CI 86-98%), 69% (95% CI 39-90%), and 100% (95% CI 94-100%), respectively. Twelve abbreviated ultrasounds were followed by a second NEC ultrasound within 5 days. Five follow-up ultrasounds demonstrated new high- or low-risk findings, but the new findings did not correlate with a change in outcome as predicted by the initial ultrasound.

CONCLUSION

An abbreviated NEC ultrasound can be of clinical utility in predicting poor outcomes, particularly during non-business hours when resources are limited.

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.

Comparison of simultaneous auscultation and ultrasound for clinical assessment of bowel peristalsis in neonates

Introduction

Assessment of bowel health in ill preterm infants is essential to prevent and diagnose early potentially life-threatening intestinal conditions such as necrotizing enterocolitis. Auscultation of bowel sounds helps assess peristalsis and is an essential component of this assessment.

Aim

We aim to compare conventional bowel sound auscultation using acoustic recordings from an electronic stethoscope to real-time bowel motility visualized on point-of-care bowel ultrasound (US) in neonates with no known bowel disease.

Methods

This is a prospective observational cohort study in neonates on full enteral feeds with no known bowel disease. A 3M™ Littmann® Model 3200 electronic stethoscope was used to obtain a continuous 60-s recording of bowel sounds at a set region over the abdomen, with a concurrent recording of US using a 12l high-frequency Linear probe. The bowel sounds heard by the first investigator using the stethoscope were contemporaneously transferred for a computerized assessment of their electronic waveforms. The second investigator, blinded to the auscultation findings, obtained bowel US images using a 12l Linear US probe. All recordings were analyzed for bowel peristalsis (duration in seconds) by each of the two methods.

Results

We recruited 30 neonates (gestational age range 27-43 weeks) on full enteral feeds with no known bowel disease. The detection of bowel peristalsis (duration in seconds) by both methods (acoustic and US) was reported as a percentage of the total recording time for each participant. Comparing the time segments of bowel sound detection by digital stethoscope recording to that of the visual detection of bowel movements in US revealed a median time of peristalsis with US of 58%, compared to 88.3% with acoustic assessment (p < 0.002). The median regression difference was 26.7% [95% confidence interval (CI) 5%-48%], demonstrating no correlation between the two methods.

Conclusion

Our study demonstrates disconcordance between the detection of bowel sounds by auscultation and the detection of bowel motility in real time using US in neonates on full enteral feeds and with no known bowel disease. Better innovative methods using artificial intelligence to characterize bowel sounds, integrating acoustic mapping with sonographic detection of bowel peristalsis, will allow us to develop continuous neonatal bowel sound monitoring devices.

Current Practices, Challenges, and Recommendations in Enteral Nutrition After Necrotizing Enterocolitis

Necrotizing enterocolitis (NEC) is a neonatal disease with high mortality and morbidity. There is a lack of evidence-based recommendations on nutritional rehabilitation following NEC, and much of the current practice is guided by institutional policies and expert opinions. After a diagnosis of NEC, infants are exposed to an extended period of bowel rest and a prolonged course of antibiotics. Recognizing the patient characteristics that predict nutritional tolerance, early initiation of enteral nutrition, minimizing periods of bowel rest and antibiotic exposure, and standardization of dietary practices are the mainstay of post-NEC nutrition.

Application of abdominal ultrasonography in surgical necrotizing enterocolitis: a retrospective study

Background

Necrotizing enterocolitis (NEC) is a severe inflammatory bowel disease that may lead to perforation, causing high morbidity and mortality in preterm infants. Abdominal ultrasound (AUS) has been shown to provide benefits in diagnosing and managing NEC in recent years.

Objective

This study focused on the utility of AUS in the diagnosis and evaluation of surgical NEC.

Patients and methods

In this retrospective study, available data of the patients diagnosed from January 2019 to June 2022 were reviewed. The sensitivity and specificity of AUS in diagnosing a perforation were analyzed. Typical cases for the application of AUS in monitoring and evaluating the progression, complications, and sequela of NEC were described.

Results

There were 69 neonates diagnosed with NEC and examined by AUS, of whom eight patients developed a perforation. AUS was used for diagnosing a perforation in eight patients with key features of pneumoperitoneum and/or complex ascites, allowing us to find four locations of perforation, with a sensitivity and specificity of 100%.

Conclusion

AUS plays an important role in diagnosing and evaluating surgical NEC in newborn infants, with good sensitivity and specificity.

Abdominal Surgical Emergencies in Neonates

Abdominal surgical emergencies are relatively common in neonates. Some of them are related to congenital diseases such as intestinal atresia and intestinal malrotation, whereas some are entirely postnatal conditions such as necrotizing enterocolitis and gastric perforation. While there is a wide range of clinical severity for these conditions, outcomes are most favorable with prompt identification and expeditious treatment. In this review, we describe the most common neonatal abdominal surgical emergencies, highlight the signs that can help with early detection, and explain the approach to diagnosis and management.

Updates and recommendations on the surgical management of NEC

Necrotizing enterocolitis is a severe gastrointestinal disease of the infant. It most commonly targets those that are born prematurely. NEC has been associated with initiation of feeds and in most cases, it can be managed with antibiotics and bowel rest. However, in up to half of the cases, intestinal perforation, peritonitis, and failure of medical treatment will require surgical intervention. The following review will discuss the surgical approach to managing NEC, based on an updated review of practice patterns and recently published literature.

US for Evaluation of Acute Abdominal Conditions in Neonates

US is the imaging modality of choice for evaluation of a variety of abdominal conditions, and in recent years it has also become useful and promising as a bedside technique for assessment of acute abdominal conditions in neonates. Bedside US can help, complement, and sometimes replace radiographic or contrast-enhanced studies in critically ill and labile neonates who are difficult to transport to the fluoroscopy suite. Some of the features of bedside US can be applied as point-of-care US (POCUS) of the sick neonate. Some of the abdominal conditions in neonates that can be assessed and monitored with bedside US are necrotizing enterocolitis and its complications, malrotation with a midgut volvulus, segmental volvulus, meconium peritonitis, and complicated inguinal hernia. High-resolution US with the use of 15-MHz and higher-frequency probes allows characterization of the bowel anatomy and features of intestinal abnormalities in neonates in fine detail. Color Doppler US and microvascular imaging improve accuracy in the detection and characterization of bowel vascularity, which is important in the treatment and follow-up of patients with intestinal conditions. ^© RSNA, 2023 Quiz questions for this article are available through the Online Learning Center. The slide presentation from the RSNA Annual Meeting is available for this article.

Predicting clinical outcomes using artificial intelligence and machine learning in neonatal intensive care units: a systematic review

BACKGROUND

Advances in technology, data availability, and analytics have helped improve quality of care in the neonatal intensive care unit.

OBJECTIVE

To provide an in-depth review of artificial intelligence (AI) and machine learning techniques being utilized to predict neonatal outcomes.

METHODS

The PRISMA protocol was followed that considered articles from established digital repositories. Included articles were categorized based on predictions of: (a) major neonatal morbidities such as sepsis, bronchopulmonary dysplasia, intraventricular hemorrhage, necrotizing enterocolitis, and retinopathy of prematurity; (b) mortality; and (c) length of stay.

RESULTS

A total of 366 studies were considered; 68 studies were eligible for inclusion in the review. The current set of predictor models are primarily built on supervised learning and mostly used regression models built on retrospective data.

CONCLUSION

With the availability of EMR data and data-sharing of NICU outcomes across neonatal research networks, machine learning algorithms have shown breakthrough performance in predicting neonatal disease.

Ultrasound for necrotizing enterocolitis: how can we optimize imaging and what are the most critical findings?

Necrotizing enterocolitis (NEC) is a common condition in the neonatal intensive care unit that continues to present challenges in terms of diagnosis and management. Traditionally NEC has been diagnosed and managed by clinical and radiographic findings, but US has shown promise in characterizing and prognosticating NEC. In this manuscript we review the abdominal US technique for NEC, the clinical significance of individual sonographic findings of NEC, and how US can be integrated in the clinical decision process for diagnosing and managing NEC. We also discuss the potential value-added role of a limited abdominal US protocol that focuses on the sonographic findings most indicative of a poor prognosis to include pneumoperitoneum, complex free fluid and focal fluid collections.

Neonatal Gastrointestinal Emergencies: A Radiological Review

BACKGROUND

Abdominal emergencies in neonates require surgical management in almost all cases and complications may include bowel perforation, sepsis, shock, and even death. Radiological imaging has become a very important aid in the clinical setting as it shortens time to diagnosis.

OBJECTIVE

The objective of this review is to discuss the more prevalent neonatal gastrointestinal emergencies, review appropriate imaging options, and illustrate common radiological presentations of these entities.

CONCLUSION

Despite advancements in imaging techniques, it is important to keep in mind that neonates have a higher susceptibility to the adverse effects of ionizing radiation, and therefore radiography and ultrasonography remain the main diagnostic modalities for ruling out the diseases with the worst prognosis. Other modalities (fluoroscopy, computed tomography, and magnetic resonance imaging) may have limited use in very specific conditions. All providers in an emergency department should be familiar with the basic radiological findings that may indicate a gastrointestinal emergency, especially in health institutions that do not have 24-h radiologist coverage.