Point-of-care ultrasound evaluation of suspected necrotizing enterocolitis in the ED.

Necrotizing enterocolitis (NEC) is a rare but life-threatening diagnosis in infants presenting with bilious emesis, abdominal distension, or bloody stools. Ultrasonography has been advocated as an alternative initial imaging modality to abdominal radiography, and may be superior in the evaluation of NEC. We describe the use of point-of-care ultrasound (PoCUS) in the evaluation of suspected NEC in the emergency department (ED) when the ability to obtain immediate abdominal x-ray (AXR) was delayed due to pandemic conditions. A pre-term infant with history of bowel resection presented with non-bilious emesis, bloody stools, and slight abdominal distension. Evaluation with PoCUS identified pneumatosis intestinalis and pneumoperitoneum, which were confirmed on subsequent AXR. Pneumatosis intestinalis in a neonate is highly suggestive of NEC, but seen by itself, can be associated with milk protein allergy and Food Protein Induced Enterocolitis syndrome (FPIES). Pneumoperitoneum is considered an indication for operative intervention for NEC. The infant was re-admitted to the NICU for suspected NEC. NEC is a rare, but potentially surgical diagnosis in infants as can be FPIES, but not milk protein allergy. NEC can be identifiable using PoCUS to search for a constellation of findings that include pneumatosis intestinalis, pneumoperitoneum, free peritoneal fluid, and portal venous gas. These findings have been previously described in the PoCUS literature for other diseases, but not for a case of suspected NEC presenting to the ED.

Posthemorrhagic hydrocephalus management in patients with necrotizing enterocolitis: a monocentric experience.

PURPOSE: Posthemorrhagic hydrocephalus (PHH) and necrotizing enterocolitis (NEC) are two comorbidities associated with prematurity. The management of patients with both conditions is complex and it is necessary to intercept them to avoid meningitis and multilocular hydrocephalus. METHODS: In a single-center retrospective study, we analyzed 19 patients with NEC and PHH admitted from 2012 to 2022. We evaluated perinatal, imaging, and NEC-related data. We documented shunt obstruction and infection and deaths within 12 months of shunt insertion. RESULTS: We evaluated 19 patients with NEC and PHH. Six cases (31.58%) were male, the median birth weight was 880 g (650-3150), and the median gestational age was 26 weeks (23-38). Transfontanellar ultrasound was performed on 18 patients (94.74%) and Levine classification system was used: 3 cases (15.79%) had a mild Levine index, 11 cases (57.89%) had moderate, and 5 cases (26.32%) were graded as severe. Magnetic resonance showed intraventricular hemorrhage in 14 cases (73.68%) and ventricular dilatation in 15 cases (78.95%). The median age at shunt insertion was 24 days (9-122) and the median length of hospital stay was 120 days (11-316). Sepsis was present in 15 cases (78.95%). NEC-related infection involved the peritoneal shunt in 4 patients and 3 of them had subclinical NEC. At the last follow-up, 6 (31.58%) patients presented with psychomotor delay. No deaths were reported. CONCLUSIONS: Although recognition of subclinical NEC is challenging, the insertion of a ventriculoperitoneal shunt is not recommended in these cases and alternative treatments should be considered to reduce the risk of meningitis and shunt malfunction.

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.

A Novel Integrated Clinical-Biochemical-Radiological and Sonographic Classification of Necrotizing Enterocolitis.

OBJECTIVE: To evaluate the sensitivity and specificity of clinical, laboratory, and radiological markers and the neonatologist-performed intestinal ultrasound (NP-IUS) for treatment interventions in preterm neonates who developed necrotizing enterocolitis (NEC). STUDY DESIGN: This was a case-control study of preterm neonates < 35 weeks with a diagnostic workup for NEC. The diagnostic workup included NP-IUS performed by trained neonatologists using a standard protocol, abdominal roentgenogram (AXR), and laboratory investigations. Intestinal ultrasound (IUS) performed by two neonatologists was standardized to detect 11 injury markers. AXRs were read independently by experienced pediatric radiologists. The investigators who retrospectively interpreted the IUS were blinded to the clinical and treatment outcomes. RESULTS: A total of 111 neonates were assessed. Fifty-four did not require intervention and formed the control group. Twenty cases were treated medically, 21 cases were treated with late surgery for stricture or adhesions, and 16 were treated with early surgery. The integrated model of cumulative severity of ultrasound markers, respiratory and hemodynamic instability, abdominal wall cellulitis, and C- reactive protein > 16 mg/L had an area under the curve (AUC) of 0.89 (95% confidence interval [CI]: 0.83-0.94%, p < 0.0001) for diagnosing NEC requiring surgical intervention. We also investigated the utility of Bell's classification to diagnose either the need for surgery or death, and it had an AUC of 0.74 (95% CI: 0.65-0.83%, p < 0.0001). CONCLUSION: In this cohort, a combination of specific IUS markers and clinical signs of instability, abdominal wall cellulitis, plus laboratory markers were diagnostic of NEC requiring interventions. KEY POINTS: · The diagnosis of necrotizing enterocolitis requires a combination of markers.. · The combination of specific ultrasound markers, clinical signs, and laboratory markers were diagnostic of NEC requiring intervention.. · The intestinal ultrasound performed by a trained neonatologist was the most sensitive diagnostic marker of NEC requiring surgical intervention..

THE ROLE OF RADIODIAGNOSIS OF NECROTIZING ENTEROCOLITIS IN PREMATURE INFANTS.

Necrotizing enterocolitis (NEC) is the most often encountered pathology of newborns and always requires an emerging surgery in cases of perforation. An active study of more important diagnostic factors at early stages of a disease is one of the first aims of neonatologists and pediatric surgeons. This study was therefore designed to examine the state of diagnostic problems in patients presenting with Necrotizing enterocolitis, identification of possible ways of the improvement of a patient's diagnosis suffering from Necrotizing enterocolitis and patients with perforated enterocolitis, definition of the possibilities of roentgenologic methods for the determination of a disease stage of Necrotizing enterocolitis. 69 infants aged one day to 1.5 months admitted at surgical department of K.Y. Farajeva Research Institute of Pediatrics between 2016 and 2021 inclusive were treated and evaluated. The capabilities of plain radiography and using radiocontrast methods of study to reveal NEC stages have been evaluated. The use of CSM has advantages: simplicity and accessibility in use, high diagnostic informativeness, identification of objective signs of NEC in 2-3 hours of research, allows assessing the severity of the patient's condition at an early date and timely correct treatment.

Association of new sonographic features with outcome in neonates with necrotizing enterocolitis.

BACKGROUND: We have recently noted some sonographic features in necrotizing enterocolitis that have received little or no attention in the current literature. These include thickening of the mesentery, hyperechogenicity of intraluminal intestinal contents, abnormalities of the abdominal wall, and poor definition of the intestinal wall. It has been our impression that the above four sonographic findings are generally seen in neonates with more severe necrotizing enterocolitis and may be useful in predicting outcome. OBJECTIVES: The aim of this study is, firstly, to review a large series of neonates, known to have clinical NEC, to document how frequently the above four sonographic features occur in neonates with necrotizing enterocolitis and, secondly, to determine whether they are predictive of outcome. MATERIALS AND METHODS: We retrospectively analyzed the clinical, radiographic, sonographic, and surgical findings in neonates with necrotizing enterocolitis between 2018 and 2021. The neonates were categorized into two groups based on outcome. Group A included neonates with a favorable outcome defined as successful medical treatment with no surgical intervention. Group B included neonates with an unfavorable outcome defined as failed medical treatment requiring surgery (for acute complications or late strictures) or death because of necrotizing enterocolitis. The sonographic examinations were reviewed with attention to the features of mesenteric thickening, hyperechogenicity of intraluminal intestinal contents, abnormalities of the abdominal wall, and poor definition of the intestinal wall. We then determined the association of these four findings with the two groups. RESULTS: We included 102 neonates with clinical necrotizing enterocolitis: 45 in group A and 57 in group B. Neonates in group B were born at a significantly earlier gestational age (median 25 weeks, range 22-38 weeks) and had a significantly lower birth weight (median 715.5 g, range 404-3120 g) than those in group A (median age 32 weeks, range 22-39 weeks, p = 0.003; median weight 1190 g, range 480-4500 g, p = 0.002). The four sonographic features were present in both study groups but with different frequency. More importantly, all four were statistically significantly more frequently present in neonates in group B compared to group A: (i) mesenteric thickening, A = 31 (69%), B = 52 (91%), p = 0.007; (ii) hyperechogenicity of intestinal contents, A = 16 (36%), B = 41 (72%), p = 0.0005; (iii) abnormalities of the abdominal wall, A = 11 (24%), B = 35 (61%), p = 0.0004; and (iv) poor definition of the intestinal wall, A = 7 (16%), B = 25 (44%), p = 0.005. Furthermore, the proportion of neonates with more than two signs was greater in group B compared to group A (Z test, p < 0.0001, 95% CI = 0.22-0.61). CONCLUSION: The four new sonographic features described were found to occur statistically significantly more frequently in those neonates with an unfavorable outcome (group B) than in those with a favorable outcome (group A). The presence or absence of these signs should be included in the sonographic report to convey the radiologists concern regarding the severity of the disease in every neonate, suspected or known to have necrotizing enterocolitis, as the findings may impact further medical or surgical management.

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.

A systematic review and meta-analysis of the role of Doppler ultrasonography of the superior mesenteric artery in detecting neonates at risk of necrotizing enterocolitis.

The role of postnatal Doppler measurements of the superior mesenteric artery (SMA) in detecting neonates at risk of necrotizing enterocolitis (NEC) remains uncertain; therefore, we systematically reviewed and meta-analyzed the existing evidence regarding the usefulness of SMA Doppler measurements in detecting neonates at risk for NEC. We used the Preferred Reporting Items for Systematic reviews and Meta-Analyses guidelines, and we included studies which reported the following Doppler ultrasonography indices: peak systolic velocity, end-diastolic velocity, time average mean velocity, differential velocity, pulsatility index (PI) and resistive index. Eight studies were eligible for inclusion in the meta-analysis. Evidence suggested that, during the first postnatal day, neonates who developed NEC had a significantly higher peak systolic velocity (mean difference of 2.65 cm/s (95% confidence interval [CI] 1.23, 4.06, overall effect Z=3.66, P<0.001)), higher PI (mean difference of 1.52 (95% CI 0.00, 3.04, Z=1.96, P=0.05)) and higher resistive index (mean difference of 1.09 (95% CI 0.59, 1.60, Z=4.24, P<0.001)), compared to neonates who did not develop NEC. However, our findings do not support a strong association between the Doppler ultrasound indices and development of NEC at the time of disease onset. This meta-analysis suggests that first postnatal day SMA Doppler parameters, namely peak systolic velocity, PI and resistive index, are higher in neonates who develop NEC. On the other hand, the aforementioned indices are of uncertain significance once the diagnosis of NEC has been established.

In vivo phenotyping of the microvasculature in necrotizing enterocolitis with multicontrast optical imaging.

OBJECTIVE: Necrotizing enterocolitis (NEC) is the most prevalent gastrointestinal emergency in premature infants and is characterized by a dysfunctional gut microcirculation. Therefore, there is a dire need for in vivo methods to characterize NEC-induced changes in the structure and function of the gut microcirculation, that is, its vascular phenotype. Since in vivo gut imaging methods are often slow and employ a single-contrast mechanism, we developed a rapid multicontrast imaging technique and a novel analyses pipeline for phenotyping the gut microcirculation. METHODS: Using an experimental NEC model, we acquired in vivo images of the gut microvasculature and blood flow over a 5000 × 7000 µm2 field of view at 5 µm resolution via the following two endogenous contrast mechanisms: intrinsic optical signals and laser speckles. Next, we transformed intestinal images into rectilinear "flat maps," and delineated 1A/V gut microvessels and their perfusion territories as "intestinal vascular units" (IVUs). Employing IVUs, we quantified and visualized NEC-induced changes to the gut vascular phenotype. RESULTS: In vivo imaging required 60-100 s per animal. Relative to the healthy gut, NEC intestines showed a significant overall decrease (i.e. 64-72%) in perfusion, accompanied by vasoconstriction (i.e. 9-12%) and a reduction in perfusion entropy (19%)within sections of the vascular bed. CONCLUSIONS: Multicontrast imaging coupled with IVU-based in vivo vascular phenotyping is a powerful new tool for elucidating NEC pathogenesis.

Value of abdominal ultrasonography in predicting intestinal resection for premature infants with necrotizing enterocolitis.

BACKGROUND: Abdominal ultrasonography (AUS) has been suggested to be valuable in the early detection of necrotizing enterocolitis (NEC). OBJECTIVE: Here, we intended to assess the efficiency of abdominal ultrasound in terms of predicting bowel resection in infants with NEC. METHODS: From January 2018 to March 2021, 164 hospitalized children with NEC who underwent surgical management were enrolled. The enrolled infants were separated into two groups according to whether they underwent bowel resection. We reviewed the clinical data, as well as dynamic sonographic and abdominal radiographic (AR) parameters. The potential performance of AUS parameters was identified and compared with that of AR using a logistic regression analysis and receiver operating characteristic (ROC) curve analysis. RESULTS: Several parameters were detected to be statistically significant in predicting the occurrence of bowel resection, including thick to thin transformation [p < 0.001, odds ratios (OR), 4.38; 95% confidence interval (CI) 2.26-8.52], absence of peristalsis certain areas (p = 0.001, OR, 2.99; 95% CI 1.53-5.86), absence of bowel wall perfusion (p < 0.001, OR 10.56; 95% CI 5.09-21.90), and portal venous gas (p = 0.016, OR, 2.21; 95% CI 1.12-4.37). Furthermore, the ROC curve analysis showed significant differences (p = 0.0021) in the area under the receiver operating curve (AUROC) for the logistic models of AUS (AUROC: 0.755, 95% CI 0.660-0.849) and AR (AUROC: 0.693, 95% CI 0.597-0.789) for the prediction of intestinal resection. CONCLUSIONS: A dynamic AUS examination play an important role to indicate the potential for bowel loss during the surgery.

A new intestinal ultrasound integrated approach for the management of neonatal gut injury.

Clinical management of gut injury has been a challenge to the clinician since the first description of necrotizing enterocolitis (NEC) about 50 years ago, and it is still poorly defined. Most of the diagnostic markers are non-specific, and there is no consensus yet on a reliable gold standard for diagnosis. This report describes our approach to integrating point of care intestinal ultrasound (IUS) as the primary radiological assessment modality with other clinical and biochemical markers. CONCLUSIONS: This is the first clinical guideline integrating point of care IUS as a routine assessment of the gut injury. This integrated algorithm improves the quality of care of the gut injury, provides a more accurate diagnosis of NEC, and differentiates other categories of gut injury. WHAT IS KNOWN: • Necrotizing enterocolitis is a poorly defined disease, and the routine assessment relying on AXR does not differentiate NEC from other categories of gut injury. WHAT IS NEW: • Integrating point of care IUS with the routine clinical assessment of gut injury enables the gut injury to be classified according to the triggering factors and severity; this helps target the appropriate management.

Feasibility and acceptability of a diagnostic randomized clinical trial of bowel ultrasound in infants with suspected necrotizing enterocolitis.

We conducted a pilot diagnostic randomized clinical trial (RCT) to examine the feasibility, acceptability, and preliminary outcomes of adding bowel ultrasound (BUS) to the diagnostic evaluation for necrotizing enterocolitis (NEC). Infants ≤ 32 weeks' gestational age with NEC concern were randomized to undergo abdominal X-ray (AXR) or AXR + BUS. The primary outcome was study feasibility. Secondary outcomes included rates of NEC diagnosis and duration of treatment with bowel rest and antibiotics. A total of 56 infants were enrolled; 16 developed NEC concern and were randomized. Rates of recruitment (56/82 = 68%), retention (16/16 = 100%), and protocol compliance (126/127 = 99%) met pre-specified thresholds for feasibility. No significant differences in rates of NEC diagnosis were found between the two groups. Durations of bowel rest and antibiotic treatment were also similar.   Conclusion: Our study supports the feasibility of conducting a definitive diagnostic RCT to establish safety and efficacy of BUS for NEC.   Clinical trial registration: The study was registered at https://clinicaltrials.gov (NCT03963011). What is Known: • Bowel ultrasound (BUS) is increasingly being utilized as an adjunct to abdominal radiographs in evaluating for necrotizing enterocolitis (NEC). • The impact of BUS on patient outcomes is unknown. What is New: • A diagnostic randomized controlled trial study design to determine safety and effectiveness of adding BUS to NEC evaluation is feasible and acceptable.

Portal Vein Gas in Neonates: Predicting Clinical Treatment Outcomes From Ultrasound Findings.

OBJECTIVES: To identify sonographic findings that predict clinical outcomes in neonates with portal vein gas. METHODS: This retrospective study included neonates with portal vein gas detected using ultrasound (US). The US images were reviewed by a pediatric radiologist. US findings included the extent and amount of portal vein gas, mesenteric vein gas, intramural gas, bowel wall thickening or thinning, focal discontinuity of the bowel wall, ascites, free intra-abdominal gas, pseudocyst, gas in the other solid organs, and bowel distension. The imaging findings and demographic factors between survivors and non-survivors were statistically compared. RESULTS: The mortality rate was 26% (39 survivors, 14 non-survivors) when iatrogenic and idiopathic causes were excluded. The causes of portal vein gas were determined to be necrotizing enterocolitis (n = 33), bowel distension or obstruction (n = 12), fetal hydrops (n = 4), pneumothorax (n = 3), immediate postoperative state for bowel perforation (n = 1), and umbilical vein catheterization (n = 9) based on surgical findings (n = 20) and clinical information (n = 46). Gas within the mesenteric vein and the other solid organs, gestational age, and birth weight were significantly different between survivors and those who succumbed (P < .05). CONCLUSION: Gas within the mesenteric vein and other solid organs is a US finding that may predict poor outcomes in neonates with portal vein gas.

The role of ultrasound in necrotizing enterocolitis.

Ultrasound has proved to be a useful modality for enhancing the diagnostic accuracy of necrotizing enterocolitis and associated complications. The standard imaging algorithm for evaluating necrotizing enterocolitis includes radiographs and clinical symptoms, the combination of which constitutes the Bell criteria. Major limitations of using the Bell criteria for diagnosing and clinically managing necrotizing enterocolitis include low diagnostic accuracy of radiographs and nonspecific symptomatology of preterm infants. In this regard, US can offer additional insights into bowel health by helping to characterize bowel motility, echogenicity, thickness, pneumatosis and perfusion. Extramural findings such as portal venous gas, nature and extent of ascites, and pneumoperitoneum can also be assessed. Recently, contrast-enhanced US was explored in a case series of preterm bowel disease and its diagnostic utility warrants further investigation. This article reviews the US features of necrotizing enterocolitis and highlights the role of US as a complement to radiographs, as well as the emerging use of contrast-enhanced US in necrotizing enterocolitis.

A role for abdominal ultrasound in discriminating suspected necrotizing enterocolitis in congenital heart disease patients.

PURPOSE: We evaluated the diagnostic utility of abdominal ultrasound (AUS), an adjunct to abdominal X-ray (AXR), for necrotizing enterocolitis (NEC) in congenital heart disease (CHD) patients. METHODS: 86 patients with suspected NEC from 2009 to 2018 were classified as with CHD (n = 18) if they required cardiac intervention versus without CHD (n = 68). Clinical and radiological data were collected, including AXR and AUS concordance. Wilcoxon rank-sum test and Fisher's exact test were performed. RESULTS: CHD patients had higher birth weights (p < 0.001) and gestational ages (p < 0.001) than non-CHD patients. CHD patients presented more frequently with hypotension (p = 0.041) and less frequently with bilious emesis (p < 0.001). Overall, CHD patients were less likely to have AUS findings of pneumatosis (33.3 vs. 72.1%; p = 0.005) and decreased mural flow (0 vs. 20.6%; p = 0.035) compared to non-CHD patients. On concordance analysis, CHD patients had 3.9-fold more discordant studies with pneumatosis on AXR but not on AUS (33.3 vs. 8.8%; p = 0.016) compared to non-CHD patients. Urgent surgery was required in 5.6% of CHD patients versus 16.2% of non-CHD patients. CONCLUSION: CHD patients with suspected NEC represent a distinct clinical population. AUS has particular utility in assessing findings of bowel viability in the CHD NEC population, reflecting reduced rates of surgical NEC.

Diagnostic efficacy of high-frequency ultrasound and X-ray contrast enema in colonic strictures after necrotizing enterocolitis: a retrospective study.

OBJECTIVE: To compare the efficacy of high-frequency ultrasound and X-ray contrast enema in the diagnosis of colonic strictures after necrotizing enterocolitis. METHODS: This study included pediatric patients who developed progressive abdominal distension or constipation after conservative treatment for necrotizing enterocolitis at our hospital between June 2012 and April 2020. All patients had high-frequency ultrasounds and X-ray contrast enema, and we used surgery, pathology, and telephone return visits as the reference standard. Patients with colonic strictures were confirmed by surgery and pathology. A patient was considered without colonic stricture if no stricture was reported or did not have related symptoms during telephone return visits. The areas under the Receiver operating characteristic (ROC) curves were used as evaluation indexes to compare the differential efficacy of high-frequency ultrasound and X-ray contrast enema. RESULTS: A total of 81 patients have been included in this study. Among them, 49 patients were diagnosed with colonic strictures after necrotizing enterocolitis. The AUCs for high-frequency ultrasound and X-ray contrast enema were 0.990 vs 0.938, respectively (p > 0.05). CONCLUSION: The diagnostic efficacy of high-frequency ultrasound was similar to that of X-ray contrast enema, furthermore this study also demonstrates the benefits of using high-frequency ultrasound to identify colonic strictures after necrotizing enterocolitis.

Near-infrared spectroscopy as a diagnostic tool for necrotizing enterocolitis in preterm infants.

BACKGROUND: We aimed to investigate whether splanchnic tissue oxygen saturation (rsSO2) measured by near-infrared spectroscopy (NIRS) could contribute to the early diagnosis of necrotizing enterocolitis (NEC). METHODS: We retrospectively included infants with suspected NEC, gestational age <32 weeks and/or birth weight <1200 g in the first 3 weeks after birth. We calculated mean rsSO2, cerebral tissue oxygen saturation (rcSO2), variability of rsSO2 (coefficients of variation [rsCoVAR] = SD/mean), and splanchnic-cerebral oxygenation ratio ([SCOR] = rsSO2/rcSO2) in the period around the abdominal radiograph to confirm or reject NEC. RESULTS: Of the 75 infants, 21 (28%) had NEC (Bell's stage ≥2). Characteristics of infants with and without NEC differed only on mechanical ventilation and nil-per-os status. RsSO2 tended to be higher and rcSO2 lower in infants with NEC. RsCoVAR (median [range]) was lower (0.11 [0.03-0.34]) vs. 0.20 [0.01-0.52], P = 0.002) and SCOR higher (0.64 [0.37-1.36]) vs. 0.47 [0.16-1.09], P = 0.004) in NEC infants. Adjusted for postnatal age, mechanical ventilation, and nil-per-os status, a 0.1 higher rsCoVAR decreased the likelihood of NEC diagnosis with likelihood ratio (LR) 0.38 (95% CI 0.18-0.78) and a 0.1 higher SCOR increased it with LR 1.28 (1.02-1.61). CONCLUSIONS: Using NIRS, high SCOR may confirm NEC and high variability of rsSO2 may rule out NEC, when suspicion arises. IMPACT: Near-infrared spectroscopy may contribute to the diagnosis of necrotizing enterocolitis. When clinical signs are present a high splanchnic-cerebral oxygenation may indicate necrotizing enterocolitis. A low splanchnic-cerebral oxygenation ratio and high variability of splanchnic tissue oxygen saturation may rule out necrotizing enterocolitis. Whether a bedside real-time availability of the splanchnic-cerebral oxygenation ratio and variability of splanchnic tissue oxygen saturation improves NEC diagnosis needs to be further investigated.

Gut transit time, using radiological contrast imaging, to predict early signs of necrotizing enterocolitis.

BACKGROUND: Immature gut motility in preterm neonates may be a risk factor for necrotizing enterocolitis (NEC). Using preterm pigs as a model for infants, we hypothesized that intestinal dysmotility precedes NEC development. METHODS: Eighty-five preterm pigs were fed increasing amounts of milk diets to induce NEC lesions, as detected at autopsy on day 5. Gut transit time was determined on day 4 by x-ray imaging after oral intake of contrast solution. RESULTS: No clinical or radiological signs of NEC were detected on day 4, but macroscopic NEC lesions were recorded in 59% of pigs (n = 50) on day 5. Relative to pigs without NEC (noNEC, n = 35), pigs with small intestinal lesions (siNEC, n = 18) showed delayed stomach emptying time (StEmpty) and time for contrast to reach cecum (ToCecum) already on day 4. Pigs with lesions only in colon (coNEC, n = 20) showed more diarrhea, shorter ToCecum time, but longer small intestinal emptying time (SiEmpty). ToCecum time predicted siNEC and coNEC lesions with a receiver-operator characteristic area under the curve of 78-81%. CONCLUSIONS: Region-dependent changes in gut transit time is associated with early NEC development in preterm pigs. How gut dysmotility is related to NEC in preterm infants requires further investigations. IMPACT: Using preterm pigs as a model for preterm infants, we show that gut transit time, using serial x-ray contrast imaging, was changed in individuals with NEC-like lesions before they showed the typical radiological signs of NEC. Thus prolonged transit time across the entire gut was recorded when NEC lesions appeared in the small intestine but not when lesions were detected only in the colon. Until now, recordings of food transit have mainly investigated changes in the upper gut. Using serial x-rays, this study describes food transit across the entire gut and documents a region-dependent effect of NEC lesions on gut transit changes in preterm individuals. The findings provide proof of concept for use of x-ray contrast imaging as a tool to monitor gut transit in preterm pigs as models for infants. Delayed passage across the entire gut may be an early sign of small intestinal NEC, at least in pigs. More studies are needed to confirm relations in infants. In the future, it might be possible to use x-ray contrast imaging in preterm infants to better understand gut motility in relation to early NEC progression and need for medical NEC treatment.

Abdominal Ultrasound Assists the Diagnosis and Management of Necrotizing Enterocolitis.

BACKGROUND: Abdominal x-ray (KUB) routinely aids in detecting necrotizing enterocolitis (NEC), one of the most serious neonatal intestinal diseases. However, a KUB may miss up to 50% of the early signs of NEC. Recent advances in abdominal ultrasound (AUS) can expedite this diagnosis and improve clinical management. PURPOSES: To illustrate AUS findings that suggest NEC through 3 case examples. To review current literature regarding advantages and limitations of AUS compared with KUB. RESULTS: The added visualization of intra-abdominal structures with AUS compared with KUB improves the diagnosis and management of NEC. Some AUS features are highly suggestive of impending bowel perforation, while others can confirm bowel perforation despite a negative radiograph. IMPLICATIONS FOR PRACTICE: AUS expedites time to diagnosis of NEC and helps to stratify patients who may fail medical management and require surgical intervention. IMPLICATIONS FOR RESEARCH: More quality improvement studies are needed to validate an AUS protocol for the management of NEC. Advances in technology, such as contrast-enhanced ultrasound, may improve NEC detection with AUS in the future.Video Abstract available athttps://journals.lww.com/advancesinneonatalcare/Pages/videogallery.aspx.

Dual energy CT in necrotizing enterocolitis; a novel diagnostic approach.

BACKGROUND: Necrotizing enterocolitis (NEC) is one of the most important causes of morbidity and mortality in premature infants. Although there are no specific diagnostic tools, the main factors affecting prognosis are clinical and laboratory findings, and early diagnosis and treatment. In this study, we demonstrate the importance of dual-energy computed tomography (DECT) in confirming intestinal ischemia in neonates with NEC. METHODS: Patients diagnosed with NEC in a neonatal intensive care unit were staged according to modified Bell's classification, and DECT was performed on patients with NEC stages 2-A, 2-B and 3-A. According to their DECT reports, these patients were then separated into two groups: those with intestinal ischemia and those without intestinal ischemia. The patients with intestinal ischemia were evaluated using surgical reports, and the other patients were evaluated using clinical findings. RESULTS: DECT was performed in 21 patients with NEC stages 2-A, 2-B and 3-A. Twelve patients (57.1%) without ischemia were followed up without surgery. Nine patients (42.9%) with ischemia on DECT were operated on, and resection and anastomosis or ileostomy and colostomy were performed. DISCUSSION: In patients with NEC, DECT significantly increases overall diagnostic confidence in assessing intestinal necrosis when compared with traditional diagnostic methods.