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.

Abdominal ultrasound findings contribute to a multivariable predictive risk score for surgical necrotizing enterocolitis: A pilot study.

BACKGROUND: Abdominal ultrasound (AUS) is a promising adjunct to abdominal x-ray (AXR) for evaluating necrotizing enterocolitis (NEC). We developed a multivariable risk score incorporating AUS to predict surgical NEC. METHODS: 83 patients were evaluated by AXR and AUS for suspected NEC. A subset had surgical NEC. Multivariate logistic regression determined predictors of surgical NEC, which were incorporated into a risk score. RESULTS: 14/83 patients (16.9%) had surgical NEC. 10/83 (12.0%) patients required acute intervention, while 4/83 (4.8%) patients only required delayed surgery. Four predictors of surgical NEC were identified: abdominal wall erythema (OR: 8.2, p = 0.048), portal venous gas on AXR (OR: 29.8, p = 0.014), and echogenic free fluid (OR: 17.2, p = 0.027) and bowel wall thickening (OR: 12.5, p = 0.030) on AUS. A multivariable risk score incorporating these predictors had excellent area-under-the-curve of 0.937 (95% CI: 0.879-0.994). CONCLUSIONS: AUS, as an adjunct to physical exam and AXR, has utility for predicting surgical NEC.

Is Abdominal Sonography a Useful Adjunct to Abdominal Radiography in Evaluating Neonates with Suspected Necrotizing Enterocolitis?

BACKGROUND: Abdominal sonography (AUS) is emerging as a potentially valuable adjunct to conventional abdominal radiography (AXR) in the setting of suspected necrotizing enterocolitis (NEC). We sought to evaluate concordance between AUS and AXR for signs of NEC to better understand the potential advantages and disadvantages of AUS. As a secondary aim, we characterized AUS-specific findings and evaluated the association of imaging results with clinical outcomes. STUDY DESIGN: Hospitalized infants with clinical concern for NEC from 2009 to 2018 were included in this multicenter retrospective review. All infant patients had at least 1 paired AXR followed by an AUS within 24 hours. Findings were abstracted from written radiology reports. Cohen's κ, nonparametric Mann-Whitney U test, and quantile regression were used to evaluate chance-corrected levels of agreement for concordance analyses and associations with clinical outcomes. RESULTS: In total, 66 patients and 96 paired studies were evaluated. Agreement between the 2 imaging modalities was 61 of 96 (63.5%) for pneumatosis (κ = 0.29; 95% CI, 0.10 to 0.48), 79 of 96 (82.3%) for portal venous gas (κ = 0.07; 95% CI, 0.00 to 0.47), and 91 of 96 (94.8%) for pneumoperitoneum (κ = 0.52; 95% CI, 0.11 to 0.93). Each finding was present more frequently on AUS than AXR. On AUS, pneumatosis and focal fluid collection were independently associated with a longer antibiotic course (4.1 days longer; p = 0.03 and 21.3 days longer; p < 0.001, respectively). CONCLUSIONS: AUS holds promise as a useful adjunct to radiography for neonates with possible NEC. It might be more sensitive for the presence or absence of bowel ischemia and can reveal findings not detectable by radiography, which can aid provider decision-making.