European Journal of Cardiovascular Medicine

Intestinal obstruction is a common cause of acute abdomen in children and can present from the neonatal period through late childhood. The etiological spectrum is broad, ranging from congenital anomalies and Hirschsprung-related obstruction in infants to intussusception, bands or adhesions, hernias, and volvulus in older children. Symptoms such as vomiting, abdominal distension, pain or irritability, and constipation are often nonspecific, and early clinical differentiation between simple obstruction and complicated obstruction is difficult.

Imaging therefore becomes central to triage. Plain abdominal radiography is widely available and rapidly identifies gross obstruction patterns, air-fluid levels, and pneumoperitoneum. Ultrasonography adds dynamic evaluation of peristalsis, bowel wall thickness, and free fluid, and it can show etiology-specific signs such as the target sign in intussusception and the whirlpool sign in midgut volvulus [13,14]. Contemporary surgical imaging guidance emphasizes a stepwise approach, using radiographs and ultrasound early and reserving CT for selected cases where complication assessment or localization is essential [1,2].

The main clinical concern is strangulation with compromised perfusion, which can progress to gangrene and perforation. Classic CT features linked to strangulation include a closed-loop configuration, mesenteric edema, ascites, and abnormal bowel wall enhancement [3,4]. Ultrasound-based criteria such as bowel wall edema, reduced peristalsis, and free fluid have also been associated with strangulation in small bowel obstruction, particularly when combined with clinical suspicion [5,6]. For suspected malrotation with volvulus, pooled evidence supports high diagnostic performance of ultrasound, and color Doppler whirlpool patterns are widely described as key signs [10-12].

Complicated obstruction carries tangible clinical consequences: bowel resection, stoma creation, sepsis, longer hospital stay, and mortality risk. Pediatric series have noted that strangulation and delayed intervention increase operative complexity and adverse outcomes [7,9]. Because children can deteriorate quickly, hospitals benefit from simple imaging-linked triggers that prompt escalation, senior review, and early operative readiness. Such triggers are especially valuable where advanced imaging is selectively used and surgical teams must prioritize multiple emergencies.

Although these imaging concepts are well described, their real-world utility depends on local case-mix, imaging pathways, and presentation delays. In many resource-constrained settings, CT is selectively used, and the decision to operate is often based on composite clinical and radiological cues rather than a single modality. Locally generated evidence that links everyday radiological findings to operative severity can strengthen early triage, prioritize operating room access, and improve preoperative counselling.

The objectives of this study were to describe radiological findings on abdominal radiograph, ultrasonography, and computed tomography in children undergoing surgery for intestinal obstruction; document intraoperative etiologies and adverse outcomes; and evaluate the diagnostic performance of predefined radiological high-risk features in predicting intraoperative strangulation or ischemia.

Study design and setting: This hospital-based observational study was conducted at Azeezia Institute of Medical Sciences and Research, Kollam, Kerala, India, over one year (September 2021 to August 2022). Children were managed through coordinated care involving the Departments of Pediatrics, Radiology, and General Surgery.

Participants: Consecutive children aged 0 to 12 years who underwent operative intervention for clinically suspected intestinal obstruction were included. Children managed entirely non-operatively, those with incomplete perioperative documentation, or those lacking a baseline abdominal radiograph were excluded.

Clinical assessment and perioperative care: Demographic details, time to presentation, presenting complaints, and clinical dehydration were recorded at admission. Resuscitation included nasogastric decompression, intravenous fluids, correction of electrolyte abnormalities, and antibiotics when contamination or sepsis was suspected.

Imaging protocol: Plain abdominal radiography (supine and erect, or left lateral decubitus when erect films were not feasible) was obtained in all cases as the first-line test. Ultrasonography was performed in clinically stable children to evaluate bowel dilatation, peristalsis, wall thickening or edema, free fluid, and etiology-specific signs, including the target sign for intussusception and whirlpool sign for volvulus [10-14]. Contrast-enhanced CT was reserved for older children and diagnostically uncertain presentations, aligning with stepwise imaging recommendations for obstruction evaluation [1,2].

Definition of radiological high-risk features: High-risk imaging features were predefined using established descriptors of complicated obstruction. These included pneumoperitoneum on radiograph; marked paucity of distal gas with severe distension; moderate free fluid; bowel wall thickening or edema; reduced peristalsis on ultrasound; whirlpool sign or closed-loop configuration; and poor enhancement or ischemia suspicion on CT [3,4,6,8,11].

Intraoperative outcomes: Operative records were reviewed for level of obstruction (small or large bowel), primary etiology, presence of strangulation or ischemia (dusky bowel or compromised perfusion), gangrene, perforation, degree of peritoneal contamination, and procedures performed (reduction, adhesiolysis or band release, resection with anastomosis, stoma formation, hernia repair, or Ladd's procedure).

Postoperative outcomes: Early postoperative complications (surgical site infection, prolonged ileus, sepsis, re-exploration), length of stay, and in-hospital mortality were recorded.

Statistical analysis: Data were analyzed using descriptive statistics and presented as mean with standard deviation or median with interquartile range, and as proportions for categorical variables. Associations between imaging risk category and intraoperative outcomes were tested using chi-square or Fisher's exact test. Diagnostic performance metrics (sensitivity, specificity, positive predictive value, and negative predictive value) were calculated using intraoperative findings as the reference standard. A p-value < 0.05 was considered statistically significant.

Ethical considerations: Institutional ethical approval was obtained, confidentiality was maintained, and patient identifiers were removed prior to analysis.

A total of 50 children who underwent surgery for clinically suspected intestinal obstruction were included. The mean age was 4.6 ± 3.2 years (range: 2 days to 12 years), with male predominance (32; 64.0%). Most children presented within 48 hours of symptom onset (31; 62.0%). Vomiting (82.0%) and abdominal distension (76.0%) were the leading symptoms, while clinical dehydration was noted in 44.0% of cases.

Baseline demographic characteristics and presenting features are summarized in Table 1.

Table 1. Baseline profile and clinical presentation (n = 50)

Plain abdominal radiograph was performed in all children. Ultrasonography was performed in 46 (92.0%) and contrast-enhanced CT in 18 (36.0%), mainly in older children and in diagnostically uncertain cases. On radiograph, multiple air-fluid levels (72.0%) and dilated small-bowel loops (68.0%) were common, while pneumoperitoneum was detected in 8.0%. On ultrasonography, dilated fluid-filled loops were frequent, and target sign supported the diagnosis of intussusception in 17.4% of scanned children. Among CT-assessed cases, transition point was identified in 83.3%, and one-third showed closed-loop features or poor enhancement suggestive of ischemia.

Detailed imaging findings are presented in Table 2.

Table 2. Radiological findings (n = 50)

Note: AXR: abdominal X-ray (plain radiograph); USG: ultrasonography; CECT: contrast-enhanced computed tomography.

Small-bowel obstruction constituted the dominant intraoperative diagnosis (38; 76.0%). Intussusception (20.0%) and adhesions or bands (18.0%) were the most frequent etiologies, followed by malrotation or volvulus (14.0%). Evidence of strangulation or ischemia was found in 15 (30.0%) children; bowel gangrene was present in 8 (16.0%), and perforation in 5 (10.0%). Bowel resection with anastomosis was required in 10 (20.0%).

Intraoperative findings and procedures are shown in Table 3.

Table 3. Intraoperative findings and procedures (n = 50)

Radiological high-risk features, as predefined in the Methods, were present in 18 (36.0%) children. High-risk imaging features showed strong association with intraoperative strangulation or ischemia (chi-square test, p < 0.001).

The cross-tabulation of imaging risk category against intraoperative strangulation or ischemia is presented in Table 4.

Table 4. Imaging high-risk features vs intraoperative strangulation/ischemia (n = 50)

Using intraoperative strangulation or ischemia as the reference standard, high-risk imaging features yielded a sensitivity of 80.0% (12/15), specificity of 82.9% (29/35), positive predictive value of 66.7% (12/18), and negative predictive value of 90.6% (29/32).

Pneumoperitoneum on radiograph (n = 4) correlated strongly with operative perforation (4/4; 100%, p < 0.001). Among CT-assessed cases with high-risk patterns (closed-loop and/or ischemia suspicion; n = 6), bowel resection was required in 5 (83.3%, p < 0.01). Children presenting after 48 hours had higher rates of strangulation or ischemia (10/19; 52.6%) compared with earlier presenters (5/31; 16.1%, p = 0.006).

Postoperative complications occurred in 13 (26.0%) children, most commonly surgical site infection (6; 12.0%) and prolonged ileus (5; 10.0%). The median hospital stay was 7 days (IQR: 5-10) and was longer among those requiring resection (11 days, IQR: 9-14) than among non-resection cases (6 days, IQR: 5-8; p < 0.001). Two children (4.0%) died, both with gangrene and peritonitis.

This study evaluated how commonly available radiological signs relate to intraoperative severity in children who proceeded to surgery for intestinal obstruction. The principal finding is that a composite set of high-risk imaging features correlated strongly with operative strangulation or ischemia and demonstrated good discriminative performance. Clinically, the high negative predictive value observed in our cohort supports the use of imaging to identify children in whom ischemia is less likely at exploration, while still recognizing that operative decision-making remains multimodal.

Plain abdominal radiography retained value as an early screening test. In addition to demonstrating air-fluid levels and dilated loops, it identified pneumoperitoneum, which in our cohort aligned with operative perforation. Reviews on obstruction imaging emphasize that radiographs offer rapid recognition of free air and gross obstruction, while cross-sectional modalities refine localization and complication assessment [1,2]. These principles fit pediatric emergency pathways where rapid decisions are required.

Ultrasonography contributed both staging and etiological clarification. Free fluid, bowel wall edema, and reduced peristalsis were treated as high-risk markers in this study, consistent with criteria used to recognize strangulation in small bowel obstruction [6]. Earlier work comparing ultrasonography with conventional radiography has also highlighted improved recognition of strangulation when ultrasound is added to baseline films [5]. In children, ultrasound provides further advantage by identifying intussusception using the target sign and by supporting volvulus diagnosis through whirlpool patterns [11-14].

CT was selectively performed, but when CT suggested closed-loop obstruction or ischemia, bowel resection was common. Classic CT studies describe the relevance of closed-loop configuration, mesenteric edema, ascites, and enhancement abnormalities in complicated obstruction [3,4]. Although radiation concerns limit routine CT use in children, selective CT in diagnostically uncertain cases can sharpen operative planning and anticipate the likelihood of resection [1,2].

Time to presentation appeared to influence severity. Children presenting after 48 hours showed higher rates of ischemic findings, which aligns with pediatric series reporting that delayed presentation associates with strangulation and more invasive procedures [7,9]. These findings underline the need for early referral and for imaging-led risk stratification at first contact so that operative intervention is not deferred when high-risk features are present.

Taken together, the data support a practical approach for district and tertiary hospitals: pneumoperitoneum on radiograph should trigger urgent exploration; ultrasound markers of complicated obstruction and etiology-specific signs should expedite operative prioritization; and CT, when used, should be interpreted with established strangulation criteria to anticipate bowel viability [3,4,6,10-14]. Incorporating these triggers into institutional protocols can also improve preoperative counselling and preparedness for resection or stoma.

Limitations

This single-center study included only children who underwent surgery, so imaging performance in conservatively managed obstruction was not assessed. Computed tomography was performed in a subset, limiting modality-to-modality comparison. Imaging interpretation relied on routine clinical reports rather than blinded re-reading, and interobserver agreement was not measured. Follow-up ended at discharge, so late adhesive obstruction, stoma-related events, and long-term bowel function were not captured.

In this hospital-based cohort of children operated for intestinal obstruction, radiological findings correlated closely with intraoperative outcomes. A composite of predefined high-risk imaging features across radiograph, ultrasonography, and CT predicted strangulation or ischemia with good sensitivity and specificity, and it provided a high negative predictive value. Pneumoperitoneum accurately identified perforation, while high-risk CT patterns were frequently linked to bowel resection. Delayed presentation beyond 48 hours was associated with higher ischemic findings and longer hospitalization. Applying these imaging triggers at first contact can strengthen triage, support timely surgery, and improve perioperative preparedness in pediatric intestinal obstruction. Standardizing these criteria in emergency workflows can improve communication between clinicians and radiologists, and support clearer family counselling.

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