Small bowel obstruction-who needs an operation? A multivariate prediction model

Modified frailty index predicts postoperative morbidity in adhesive small bowel obstruction: analyzing the National Inpatient Sample 2015-2019

BACKGROUND

There are limited data identifying predictors of postoperative outcomes in adhesive small bowel obstruction (ASBO). This study used the National Inpatient Sample (NIS) to assess the efficacy of the modified frailty index (mFI) to predict postoperative morbidity among patients undergoing an operation for ASBO.

METHODS

A retrospective analysis of the NIS between September 1, 2015, and December 31, 2019, was performed to identify adult patients who underwent nonelective operative intervention for ASBO. The mFI was used to stratify patients as either frail (mFI value ≥ 0.27) or robust (mFI value < 0.27). The primary outcomes were overall in-hospital postoperative morbidity and mortality. The secondary outcomes were system-specific morbidity, length of stay (LOS), total in-hospital healthcare cost, and discharge disposition. Univariable and multivariable regressions were used.

RESULTS

Overall, 23251 robust patients and 6122 frail patients were included. Adjusted analyses demonstrated that frail patients had increased in-hospital mortality (adjusted odds ratio [aOR], 2.16; 95% CI, 1.80-2.60), postoperative morbidity (aOR, 1.63; 95% CI, 1.52-1.74), postoperative LOS (adjusted mean difference [aMD], 0.97 days; 95% CI, 0.73-1.21), and total in-hospital healthcare costs (aMD, $18,921; 95% CI, $14,608-$23,235) and were less likely to be discharged home (aOR, 0.59; 95% CI, 0.55-0.63). The findings were unchanged on subgroup analysis of patients undergoing open operation and those older than 65 years of age.

CONCLUSION

The mFI may predict postoperative outcomes for ASBO. Stratifying patients based on frailty may assist clinicians and patients in making informed decisions, setting realistic expectations, and proactively planning postoperative disposition.

Laparoscopy-Assisted Restorative Proctocolectomy with Ileal Pouch-Anal Anastomosis in Middle Colic Artery Ligation Immediately before Specimen Removal

Introduction

Restorative proctocolectomy with ileal pouch-anal anastomosis (IPAA) is the surgical procedure for ulcerative colitis (UC). Intestinal ischemia may occur if the main blood vessels are ligated at an early stage of this surgery. Considering that the blood flow in the large intestine can be maintained by preserving the middle colic artery, we have used a new IPAA method: ligating the middle colic artery immediately before removal of the specimens ("M-method"). Here, we evaluated the M-method's clinical outcomes.

Methods

Between April 2009 and December 2021, 13 patients underwent a laparoscopy-assisted IPAA procedure at our institution. The conventional method was used for 6 patients, and the M-method was used for the other 7 patients. We retrospectively analyzed the cases' clinical notes.

Results

The M-method's rate of postoperative complications (Clavien-Dindo classification grade II or more) was significantly lower than that of the conventional method (14.2% vs. 83.3%). The M-method group's postoperative stay period was also significantly shorter (average 16.4 days vs. 55.5). There were significant differences in the albumin value and the ratio of the modified GPS score 1 or 2 on the 7th postoperative day between the M- and conventional methods (average 3.15 vs. 2.5, average 4/7 vs. 6/6). However, it is necessary to consider the small number of cases and the uncontrolled historical comparison.

Conclusion

Late ligation of the middle colic artery may be beneficial for patients' post-surgery recovery and can be recommended for IPAAs in UC patients.

Laparoscopic management of intestinal obstruction in a young adult with a virgin abdomen: Unusual presentation of combined vitellointestinal duct remnants: A clinical case report

Key Clinical Message

In an 18-year-old, Meckel's diverticulum and a rare vitellointestinal fibrous band caused bowel obstruction. Clinicians should be vigilant for such anomalies, especially in young adults with virgin abdomens, as potential sources of intestinal obstruction.

Abstract

In this case report, we highlight the rarity of vitellointestinal or omphalomesenteric duct anomalies causing intestinal obstruction in the adult population. The patient, an 18-year-old male, presented to the emergency department with a two-day history of abdominal pain and vomiting. Physical examination revealed mild distension of his virgin abdomen with generalized tenderness. Abdominal X-ray displayed dilated small bowel loops, and a computed tomography scan indicated features consistent with closed-loop bowel obstruction. Diagnostic laparoscopy confirmed a vitellointestinal duct remnant as the cause of the small intestinal obstruction, involving a combined Meckel's diverticulum and vitellointestinal fibrous band. In early fetal development, the vitellointestinal duct communicates between the midgut and the yolk sac, expected to disappear during fetal growth. Failure to obliterate can lead to issues such as intestinal blockage, primarily observed in children, making occurrences in adults, as in this case, infrequent with only a few documented instances. Despite its uncommon occurrence in young adults, healthcare providers should consider the vitellointestinal duct anomalous remnant as a potential source of intestinal obstruction, particularly in individuals with a virgin abdomen. Early detection of intestinal obstruction is imperative for patient survival, facilitating prompt management and minimizing the risk of serious morbidities, ultimately contributing to a better patient outcome.

Small Bowel Obstruction in Virgin Abdomen: Predictors of Surgical Intervention Need in Resource-Limited Setting

Background

Limited evidence is available regarding the management of small bowel obstruction in the virgin abdomen (SBO-VA), with most studies excluding this entity. This study aims to assess the available data on the treatment outcomes and predictors of surgical intervention in SBO-VA.

Methods

A retrospective cross-sectional study was conducted between 2015 and 2021, including all diagnosed and managed cases of SBO-VA at Al-Nasar Hospital. Patients were divided according to the treatment approach into surgical or conservative groups. Preoperative laboratory and radiologic data were gathered and compared between groups.

Results

During the study period, 67 cases, primarily males (58.2%), with an average age of 52.2±14.4 years were assessed. Common comorbidities included diabetes (20.9%) and hypertension (16.4%). Key symptoms were rebound tenderness (82.1%) and abdominal tenderness (70.1%). The predominant etiology was adhesions (23.9%). About 46.2% received conservative treatment, 53.8% underwent urgent surgery. Conservative treatment failed in 9.4% of cases, and complications arose in 23.9%, with most being fever (17.9%). Factors necessitating surgical management included older age (58.8 ±11.7 vs 44.9 ±13.8 years, p<0.001), previous hospital admission (p<0.001), presence of abdominal tenderness (p=0.030), longer abdominal pain duration (4.0 ±0.9 vs 2.1 ±0.6 days, p<0.001), higher C- reactive protein (p= 0.033), higher white blood cell (p= 0.006), longer time to hospital presentation (75.3 ±17.2 vs 39.0 ±22.8 days, p= <0.001), small bowel thickness ≥3 cm (p=0.009), and reduced bowel enhancement (p <0.001) on computed tomography imaging. In surgical group, the need for ICU admission was higher and hospital stays were shorter than in conservative group and were statistically significant (p<0.05).

Conclusion

The main etiology of SBO-VA in our study was adhesions. Older age, previous hospital admission, longer abdominal pain duration, abdominal tenderness, increased inflammatory markers, and alarm signs on CT scans are the main factors for determining the need for urgent surgical exploration in patients with SBO-VA. To achieve prompt identification and intervention, it is crucial to maintain a high level of vigilance and awareness, even in individuals with no prior surgical history.

A nomogram for predicting the recurrence of small bowel obstruction after gastrectomy in patients with gastric cancer

BACKGROUND

This study aimed to create a nomogram for predicting the recurrence of small bowel obstruction (SBO) after gastrectomy in patients with gastric cancer (GC) in order to provide better guidance for its diagnosis and treatment.

METHODS

A total of 173 patients undergone gastrectomy and developed SBO from January 2015 to October 2022 were admitted into this case-control study. The risk factors of postoperative recurrent SBO were analyzed by univariate and multivariate regression, and a nomogram for predicting the recurrent SBO after gastrectomy was developed using R Studio.

RESULTS

Thirty-nine cases of postoperative recurrent SBO occurred among the 173 GC patients who underwent radical gastrectomy, and the percentage of recurrent SBO was 22.54% (39/173). Age [odds ratio (OR) = 0.938, p = 0.026], WBC count (OR = 1.547, p < 0.001), tumor size (OR = 1.383, p = 0.024), postoperative metastasis (OR = 11.792, p = 0.030), and the interval from gastrectomy to first SBO (OR = 1.057, p < 0.001) were all identified as independent risk factors for postoperative recurrent SBO by logistic regression analysis. The receiver operating characteristic curve, the calibration curve, the model consistency index, and the decision curve analysis showed that the nomogram had good predictive performance.

CONCLUSION

Based on these factors, we created a nomogram to predict the occurrence of postoperative recurrent SBO. This novel nomogram could serve as a crucial early warning indicator that would guide doctors to make informed decisions while managing patients with gastric cancer.

Prognostic factors to identify resolution of small bowel obstruction without need for operative management: systematic review

OBJECTIVES

To identify imaging, clinical, and laboratory variables potentially prognostic for surgical management of small bowel obstruction.

METHODS

Two researchers systematically reviewed indexed literature 2001-2021 inclusive for imaging, clinical, and laboratory variables potentially predictive of surgical management of small bowl obstruction and/or ischaemia at surgery, where performed. Risk of bias was assessed. Contingency tables for variables reported in at least 5 studies were extracted and meta-analysed to identify strong evidence of association with clinical outcomes, across studies.

RESULTS

Thirty-one studies were ultimately included, reporting 4638 patients (44 to 313 per study). 11 (35%) studies raised no risk of bias concerns. CT was the modality reported most (29 studies, 94%). Meta-analysis of 21 predictors identified 5 strongly associated with surgical intervention, 3 derived from CT (peritoneal free fluid, odds ratio [OR] 3.24, 95%CI 2.45 to 4.29; high grade obstruction, OR 3.58, 95%CI 2.46 to 5.20; mesenteric inflammation, OR 2.61, 95%CI 1.94 to 3.50; abdominal distension, OR 2.43, 95%CI 1.34 to 4.42; peritonism, OR 3.97, 95%CI 2.67 to 5.90) and one with conservative management (previous abdominopelvic surgery, OR 0.58, 95%CI 0.40 to 0.85). Meta-analysis of 10 predictors identified 3 strongly associated with ischaemia at surgery, 2 derived from CT (peritoneal free fluid, OR 3.49, 95%CI 2.28 to 5.35; bowel thickening, OR 3.26 95%CI 1.91 to 5.55; white cell count, OR 4.76, 95%CI 2.71 to 8.36).

CONCLUSIONS

Systematic review of patients with small bowel obstruction identified four imaging, three clinical, and one laboratory predictors associated strongly with surgical intervention and/or ischaemia at surgery.

CLINICAL RELEVANCE STATEMENT

Via systematic review and meta-analysis, we identified imaging, clinical, and laboratory predictors strongly associated with surgical management of small bowel obstruction and/or ischaemia. Multivariable model development to guide management should incorporate these since they display strong evidence of potential utility.

KEY POINTS

• While multivariable models incorporating clinical, laboratory, and imaging factors could predict surgical management of small bowel obstruction, none are used widely. • Via systematic review and meta-analysis we identified imaging, clinical, and laboratory variables strongly associated with surgical management and/or ischaemia at surgery. • Development of multivariable models to guide management should incorporate these predictors, notably CT scanning, since they display strong evidence of potential utility.

Predictive factors for operative intervention and ideal length of non-operative trial in adhesive small bowel obstruction

BACKGROUND

Small bowel obstruction (SBO) is responsible for 350,000 U.S. hospitalizations and costs ~ $2.3 billion annually. The current standard of care for SBO is to trial 3 to 5 days of non-operative management. This study evaluated the factors associated with operative management.

METHODS

This retrospective cohort study included adult patients admitted with adhesive SBO. Exclusions were for operative intervention within 24 h or death.

RESULTS

At baseline (N = 360), mean age was 65.9 years, 57.8% female, 72.3% white, mean BMI 26.1, 38.7% with history of SBO and 98.1% had history of abdominal surgery. Symptom onset prior to hospitalization was 1-2 days. 55.6% had successful non-operative management at discharge (median length of stay 3 days) vs. 44.4% operative conversion. In univariate analyses, BMI, SBO history, surgical history, days symptom onset, vitals, abdominal pain, obstipation, acute kidney injury, and lack of small bowel feces sign on CT scan were significantly associated with operative management. In a multivariable logistic regression, after controlling all other variables, a lack of small bowel feces sign (adjusted odds ratio, aOR = 2.25, 95% CI 1.06-4.77, p = 0.04) and history of exploratory laparotomy (aOR = 0.44, 95% CI 0.21-0.90, p = 0.03) were significantly associated with operative management. Time from admission to surgery averaged 3.89 days: small bowel resection (55/160) was 4.9 days (median = 4), compared to patients without resection (3.4 days, median = 2; p = 0.00; OR = 1.2, 95% CI 1.07-1.35).

CONCLUSIONS

A lack of small bowel feces sign can be a potential indicator for operative management and should be further explored. Since the median resolution of symptoms in the non-operative management group was ~ 2 days and a 20% higher odds for bowel resection each day surgery is delayed, the conservative trial period for adhesive SBO should not exceed 3 days.

Diagnostic accuracy of biomarkers to detect acute mesenteric ischaemia in adult patients: a systematic review and meta-analysis

BACKGROUND

Acute mesenteric ischaemia (AMI) is a disease with different pathophysiological mechanisms, leading to a life-threatening condition that is difficult to diagnose based solely on clinical signs. Despite widely acknowledged need for biomarkers in diagnosis of AMI, a broad systematic review on all studied biomarkers in different types of AMI is currently lacking. The aim of this study was to estimate the diagnostic accuracy of all potential biomarkers of AMI studied in humans.

METHODS

A systematic literature search in PubMed, The Cochrane Library, Web of Science and Scopus was conducted in December 2022. Studies assessing potential biomarkers of AMI in (at least 10) adult patients and reporting their diagnostic accuracy were included. Meta-analyses of biomarkers' sensitivity, specificity, and positive and negative likelihood ratios were conducted. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were followed, and the study quality was assessed with the QUADAS-2 tool.

RESULTS

Seventy-five studies including a total of 9914 patients assessed 18 different biomarkers in serum/plasma and one in urine (each reported in at least two studies), which were included in meta-analyses. None of the biomarkers reached a conclusive level for accurate prediction. The best predictive value overall (all studies with any type and stage of AMI pooled) was observed for Ischaemia-modified albumin (2 studies, sensitivity 94.7 and specificity 90.5), interleukin-6 (n = 4, 96.3 and 82.6), procalcitonin (n = 6, 80.1 and 86.7), and intestinal fatty acid-binding protein (I-FABP) measured in serum (n = 16, 73.9 and 90.5) or in urine (n = 4, 87.9 and 78.9). In assessment of transmural mesenteric ischaemia, urinary I-FABP (n = 2, 92.3 and 85.2) and D-dimer (n = 3, 87.6 and 83.6) showed moderate predictive value. Overall risk of bias was high, mainly because of selected study populations and unclear timings of the biomarker measurements after onset of symptoms. Combinations of biomarkers were rarely studied, not allowing meta-analyses.

CONCLUSIONS

None of the studied biomarkers had sufficient sensitivity and specificity to diagnose AMI, although some biomarkers showed moderate predictive accuracy. Future studies should focus on timing of measurements of biomarkers, distinguishing between early stage and transmural necrosis, and between different types of AMI. Additionally, studies on combinations of biomarkers are warranted. PROSPERO registration: CRD42022379341.

The Association of Polish Surgeons (APS) clinical guidelines for the use of laparoscopy in the management of abdominal emergencies. Part II

Introduction

Over the past three decades, almost every type of abdominal surgery has been performed and refined using the laparoscopic technique. Surgeons are applying it for more procedures, which not so long ago were performed only in the classical way. The position of laparoscopic surgery is therefore well established, and in many operations it is currently the recommended and dominant method.

Aim

The aim of the preparation of these guidelines was to concisely summarize the current knowledge on laparoscopy in acute abdominal diseases for the purposes of the continuous training of surgeons and to create a reference for opinions.

Material and methods

The development of these recommendations is based on a review of the available literature from the PubMed, Medline, EMBASE and Cochrane Library databases from 1985 to 2022, with particular emphasis on systematic reviews and clinical recommendations of recognized scientific societies. The recommendations were formulated in a directive form and evaluated by a group of experts using the Delphi method.

Results and conclusions

There are 63 recommendations divided into 12 sections: diagnostic laparoscopy, perforated ulcer, acute pancreatitis, incarcerated hernia, acute cholecystitis, acute appendicitis, acute mesenteric ischemia, abdominal trauma, bowel obstruction, diverticulitis, laparoscopy in pregnancy, and postoperative complications requiring emergency surgery. Each recommendation was supported by scientific evidence and supplemented with expert comments. The guidelines were created on the initiative of the Videosurgery Chapter of the Association of Polish Surgeons and are recommended by the national consultant in the field of general surgery. The second part of the guidelines covers sections 6 to12 and the following challenges for surgical practice: acute appendicitis, acute mesenteric ischemia, abdominal injuries, bowel obstruction, diverticulitis, laparoscopy in pregnancy and postoperative complications requiring a reoperation.

Predictors for success of non-operative management of adhesive small bowel obstruction

BACKGROUND

Majority of adhesive small bowel obstruction (SBO) cases can be managed non-operatively. However, a proportion of patients failed non-operative management.

AIM

To evaluate the predictors of successful non-operative management in adhesive SBO.

METHODS

A retrospective study was performed for all consecutive cases of adhesive SBO from November 2015 to May 2018. Data collated included basic demographics, clinical presentation, biochemistry and imaging results and management outcomes. The imaging studies were independently analyzed by a radiologist who was blinded to the clinical outcomes. The patients were divided into group A operative (including those that failed initial non-operative management) and group B non-operative for analysis.

RESULTS

Of 252 patients were included in the final analysis; group A (n = 90) (35.7%) and group B (n = 162) (64.3%). There were no differences in the clinical features between both groups. Laboratory tests of inflammatory markers and lactate levels were similar in both groups. From the imaging findings, the presence of a definitive transition point [odds ratio (OR) = 2.67, 95% confidence interval (CI): 0.98-7.32, P = 0.048], presence of free fluid (OR = 2.11, 95%CI: 1.15-3.89, P = 0.015) and absence of small bowel faecal signs (OR = 1.70, 95%CI: 1.01-2.88, P = 0.047) were predictive of the need of surgical intervention. In patients that received water soluble contrast medium, the evidence of contrast in colon was 3.83 times predictive of successful non-operative management (95%CI: 1.79-8.21, P = 0.001).

CONCLUSION

The computed tomography findings can assist clinicians in deciding early surgical intervention in adhesive SBO cases that are unlikely to be successful with non-operative management to prevent associated morbidity and mortality.

Unenhanced CT-based predictive model to identify small bowel necrosis in patients with mechanical small bowel obstruction

OBJECTIVES

To investigate the diagnostic value of unenhanced CT in mechanical small bowel obstruction (SBO) with small bowel necrosis, and to establish a predictive model.

METHODS

From May 2017 to December 2021, the patients with mechanical SBO admitted to our hospital were retrospectively collected. Taking pathology-confirmed small bowel necrosis as the gold standard, the experimental group was composed of patients with small bowel necrosis confirmed by pathology, and the control group was composed of patients with no intestinal necrosis confirmed by surgery or successful conservative treatment with no recurrence of intestinal obstruction during 1-month followed-up.

RESULTS

A total of 182 patients were enrolled in this study, 157 patients underwent surgery, of which 35 patients were accompanied with small bowel necrosis and 122 patients were not (33 patients with ischemic findings at surgery without necrosis). Finally, there were 35 patients in the experimental group and 147 patients in the control group. Multivariable logistic regression showed that increased attenuation of small bowel wall (P = 0.002), diffuse mesenteric haziness (P = 0.010), difference of CT value between mesenteric vessel and aorta (P = 0.025) and U-/C-shaped small bowel loop (P = 0.010) were independent risk factors for the diagnosis of mechanical SBO with small bowel necrosis. Through internal verification, the area under curve (AUC) of the predictive model reached 0.886 (95%CI: 0.824-0.947), and the calibration result was moderate.

CONCLUSION

Multiple features (increased attenuation of small bowel wall; difference of CT values between mesenteric vessel and aorta; diffuse mesenteric haziness; and U-/C-shaped small bowel loop) of unenhanced CT have clinical value in the diagnosis of mechanical SBO with small bowel necrosis. The predictive model based on these four features could achieve satisfactory efficiency.

Closed loop obstruction of small bowel: CT signs predicting successful non-surgical treatment

PURPOSE

To clarify the computed tomography (CT) findings related to successful conservative treatments in patients with closed-loop small bowel obstruction (CL-SBO) without evidence of bowel strangulation.

METHODS

Sixty-four patients (71 CT scans) diagnosed with CL-SBO by CT and received initial conservative treatments from May 2010 to August 2020 were retrospectively included. Two blinded radiologists reviewed the CT findings, including the transition zone (number, distance, and location), maximum bowel diameter, mesenteric haziness, mesenteric fluid, increased unenhanced bowel wall attenuation, decreased bowel wall enhancement, small bowel feces sign, whirl sign, bowel wall thickening, ascites, and degree of obstruction. The findings of the success and failure groups of conservative treatment were compared. Interobserver agreement was assessed for all findings.

RESULTS

Among the 71 cases, conservative treatments were successful in 42 cases (59 %) but failed in 29 cases (41 %). In multivariable analyses, the distance between the transition zones (>1 cm) and low-degree obstruction were independently associated with successful conservative treatments, with odds ratios of 6.23 and 3.52, respectively. The combination of these two CT findings exhibited a specificity of 89.7 % with a positive likelihood ratio of 3.01. Interobserver agreement of the degree of obstruction and the distance between the transition zones was almost perfect (ĸ = 0.814 and 0.914, respectively).

CONCLUSIONS

The distance between the transition zones (>1 cm) and low-grade obstruction are independent CT predictors of successful conservative treatments in CL-SBO patients. Initial conservative treatments are recommended for patients with both CT findings.

Comprehensively evaluate the short outcome of small bowel obstruction: A novel medical-economic score system

BACKGROUND

Small bowel obstruction (SBO) still imposes a substantial burden on the health care system. Traditional evaluation systems for SBO outcomes only focus on a single element. The comprehensive evaluation of outcomes for patients with SBO remains poorly studied. Early intensive clinical care would effectively improve the short-term outcomes for SBO, however, the full spectrum of the potential risk status regarding the high complication-cost burden is undetermined.

AIM

We aim to construct a novel system for the evaluation of SBO outcomes and the identification of potential risk status.

METHODS

Patients who were diagnosed with SBO were enrolled and stratified into the simple SBO (SiBO) group and the strangulated SBO (StBO) group. A principal component (PC) analysis was applied for data simplification and the extraction of patient characteristics, followed by separation of the high PC score group and the low PC score group. We identified independent risk status on admission via a binary logistic regression and then constructed predictive models for worsened management outcomes. Receiver operating characteristic curves were drawn, and the areas under the curve (AUCs) were calculated to assess the effectiveness of the predictive models.

RESULTS

Of the 281 patients, 45 patients (16.0%) were found to have StBO, whereas 236 patients (84.0%) had SiBO. Regarding standardized length of stay (LOS), total hospital cost and the presence of severe adverse events (SAEs), a novel principal component was extracted (PC score = 0.429 × LOS + 0.444 × total hospital cost + 0.291 × SAE). In the multivariate analysis, risk statuses related to poor results for SiBO patients, including a low lymphocyte to monocyte ratio (OR = 0.656), radiological features of a lack of small bowel feces signs (OR = 0.316) and mural thickening (OR = 1.338), were identified as risk factors. For the StBO group, higher BUN levels (OR = 1.478) and lower lymphocytes levels (OR = 0.071) were observed. The AUCs of the predictive models for poor outcomes were 0.715 (95%CI: 0.635-0.795) and 0.874 (95%CI: 0.762-0.986) for SiBO and StBO stratification, respectively.

CONCLUSION

The novel PC indicator provided a comprehensive scoring system for evaluating SBO outcomes on the foundation of complication-cost burden. According to the relative risk factors, early tailored intervention would improve the short-term outcomes.

Economic Consequences of Surgery for Adhesive Small Bowel Obstruction: A Population-Based Study

Background and Aims

Most patients develop adhesions after abdominal surgery, some will be hospitalized with small bowel obstruction (SBO), and some also require surgery. The operations and follow-up are expensive, but recent data of costs are scarce. The aim of this study was to describe the direct costs of SBO-surgery and follow-up, in a population-based setting. The association between cost of SBO and peri- and postoperative data was also studied.

Methods

In a retrospective cohort study, all patients (n = 402) operated for adhesive SBO in Gävleborg and Uppsala counties (2007-2012) were studied. The median follow-up was 8 years. Costs were calculated according to the pricelist of Uppsala University Hospital, Uppsala, Sweden.

Results

Overall total costs were €16.267 million, corresponding to a mean total cost per patient of €40,467 during the studied period. Diffuse adhesions and postoperative complications were associated with increased costs for SBO in a multivariable analysis (P < 0.001). Most costs, about €14 million (85%), arouse in conjunction with the SBO-index surgery period. In-hospital stay was the dominating cost, accounting for 70% of the total costs.

Conclusion

Surgery for SBO generates substantial economic burden for healthcare systems. Measures that reduce the incidence of SBO, the frequency of postoperative complication, or the length of stay have the potential to reduce this economic burden. The cost estimates from this study may be valuable for future cost-benefit analyses in intervention studies.

Diagnostic nomogram for closed-loop small bowel obstruction requiring emergency surgery

PURPOSE

This study aimed to build a diagnostic model of closed-loop small bowel obstruction (CL-SBO) using clinical information, blood test results, and computed tomography (CT) findings.

METHODS

All patients who were diagnosed with small bowel obstruction (SBO) and underwent surgery between January 1, 2018, and October 31, 2021, in the affiliated hospital of Qingdao university were reviewed, and their relevant preoperative information was collected. All variables were selected using univariate analysis and backward stepwise regression to build a diagnostic nomogram model. K-fold cross-validation and bootstrap resampling techniques were used for internal validation, and data from Qingdao Central Hospital were used for external validation. We also evaluated the diagnostic performance of each CT finding and performed subgroup analysis according to bowel ischemia in the closed-loop small bowel obstruction (CL-SBO) group.

RESULTS

A total of 219 patients (95 in the CL-SBO group and 124 in the open-loop small bowel obstruction [OL-SBO] group) were included in our research. D-dimers (median 1085 vs. 690, P = 0.019), tenderness (77.9% vs. 59.7%, P = 0.004), more than one beak sign (65.3% vs. 30.6%, P < 0.001), radial distribution (18.9% vs. 6.5%, P = 0.005), whirl sign (35.8% vs. 8.9%, P < 0.001), and ascites (71.6% vs. 53.2%, P = 0.006) were selected as the predictive variables of the nomogram. This model's Harrell's C statistic was 0.786 (95% confidence interval (CI), 0.724-0.848), and the Brier score was 0.182. The Harrell's C statistic of external validation was 0.784 (95%CI, 0.664-0.905); the Brier score was 0.190. Regarding the CT findings, radial distribution, U/C-shaped loop, and whirl sign had high specificity (93.5%, 96.0%, and 91.1%, respectively), but low sensitivity (18.9%, 8.4%, and 35.8%, respectively). D-dimer levels and tenderness were also associated with bowel ischemia.

CONCLUSION

The nomogram accurately predicted CL-SBO in patients with SBO, and surgery should be considered when patients have a high risk for developing CL-SBO.

The value of MSCT in evaluating the passability of bezoar by conservative treatment for bezoars-induced small bowel obstruction

PURPOSE

To explore the multi-slice spiral computed tomography (MSCT) imaging characteristics of patients with bezoars-induced small bowel obstruction (BI-SBO) to evaluate the risk of conservative treatment.

MATERIALS AND METHODS

This retrospective study included 72 patients with BI-SBO who underwent whole-abdominal MSCT scan within 1 day before treatment. The patients were classified as the non-pass group and pass group depending on whether bezoar can pass after conservative treatment. The CT images were observed and measured by two radiologists. Statistical analysis was performed by using Student's t test, Pearson's chi-squared test, Fisher's exact test, Logistic linear regression, and receiver operating characteristic curve (ROC).

RESULTS

The study population consisted of 72 patients with a mean age of 52.2 ± 16.2 years (32 men and 40 women with an age range of 13-81 years). There were statistical differences between the two groups in the bezoar appearance, maximum HU of bezoar, thickness of intestinal wall, mesenteric haziness, mesenteric fluid, and peritoneal fluid (P = 0.002, 0.024, 0.017, 0.006, 0.021, and 0.030). The appearance of bezoar and mesenteric haziness is independent risk factors affecting whether bezoar can be passed by the conservative treatment. Sensitivity (41.7%) was decreased, NPV (76.3%) was not significantly changed, specificity (93.8%) and PPV (76.9%) were improved when both parameters were met to assess failure of conservative treatment.

CONCLUSION

The observation of important signs by MSCT and its reconstruction technology is of great clinical value in evaluating the passability of bezoar by conservative treatment, and which can provide radiographic basis for clinical treatment selection.

Diagnosis and surgical management strategy for pediatric small bowel obstruction: Experience from a single medical center

Identifying Bowel strangulation and the approach and timing of surgical intervention for pediatric SBO are still uncertain. In this study, 75 consecutive pediatric patients with surgically confirmed SBO were retrospectively reviewed. The patients were divided into group 1 (n = 48) and group 2 (n = 27) according to the presence of reversible or irreversible bowel ischemia, which was analyzed based on the degree of ischemia at the time of operation. The results demonstrated that the proportion of patients with no prior abdominopelvic surgery was higher, the serum albumin level was lower, and the proportion of patients in which ascites were detected by ultrasonography was higher in group 2 than that in group 1. The serum albumin level was negatively correlated with ultrasonographic findings of the fluid sonolucent area in group 2. There were significant differences in the choice of surgical approach between group 1 and group 2. A symptom duration of >48 h was associated with an increased bowel resection rate. The mean length of hospital stay was shorter in group 1 than that in group 2. In conclusion, immediate surgical intervention should be considered in patients with a symptom duration of >48 h or the presence of free ascites between dilated small bowel loops on ultrasonography. Laparoscopic exploration is recommended as first-line treatment in patients with stable status.

Small Bowel Obstruction in Patients without Prior Abdominal Surgery: To Operate or Not?

INTRODUCTION

Surgical exploration is still considered mandatory in the setting of small bowel obstruction (SBO) in patients without prior intra-abdominal surgery. However, recent studies have challenged this 'classic' approach describing success with conservative non-surgical treatment. The aim of this study is to identify clinical, radiological and biochemical variables that may be associated with the absence of intra-abdominal pathology in patients with SBO who have not undergone previous surgery.

METHODS

This is a retrospective cohort study of prospectively recorded data. Patients with SBO without prior abdominal surgery who presented to a single tertiary referral medical center between 2009 and 2019 were included.

RESULTS

Eighty-seven patients were included of whom 61(70.0%) were allocated to the 'therapeutic exploration' group and 26 (30.0%) to the 'non-therapeutic exploration' group. Forty-eight patients (55.0%) had adhesions, 17.2% had closed-loop obstruction, 10.0% had an internal hernia, 27.6% had bowel ischemia and 5.7% had bowel necrosis. Although multiple clinical, laboratory, radiological and preoperative factors were examined, none were significantly associated with pathological findings during surgical exploration. There was no statistically significant difference in the incidence of complications when comparing between those groups.

CONCLUSIONS

In this series, no variables were associated with intra-abdominal pathology in patients who underwent surgery for SBO with no history of prior abdominal surgery. However, the fact that 27.0% had ischemic bowel upon surgical exploration suggests that this approach is still mandatory for this specific group of patients. Furthermore, clinicians and patients should be aware that negative exploration may be expected in up to 30.0%.

Prediction factors for ischemia of closed-loop small intestinal obstruction

A closed-loop type of intestinal obstruction leads to ischemic necrosis. There have been indicators that may predict ischemia and its severity, such as biomarkers and computed tomography scans. In addition to the usual inflammation markers, such as white blood count-neutrophil count and c-reactive protein (CRP), the most accurate predictors that have been proposed are the CRP-to-albumin ratio, the neutrophil/lymphocyte ratio and the platelet/lymphocyte ratio. Endothelin 1 is another promising biomarker of ischemia that must be assessed in daily clinical practice. Advanced age and frailty status were assessed as predictors of mortality. A timely operative procedure without any delay ensures a better outcome.

Current Management of Adhesive Small Bowel Obstructions in Children

Adhesive small bowel obstructions are a common cause of morbidity in children who underwent prior abdominal surgery. The concept of partial versus complete bowel obstruction is outdated and lacks precision to be clinically useful. Identifying patients with indications for immediate operative intervention is critical and must be recognized to limit morbidity. Clinical protocols and contrast challenge algorithms have attempted to identify patients that will resolve their bowel obstruction nonoperatively; there has been slow uptake in the pediatric patient population versus adults until recently. Incorporating predictive models and standardized contrast challenge protocols will help reduce interpractitioner variability and improve clinical outcomes.

Predicting the outcome of closed-loop small bowel obstruction by preoperative characteristics

BACKGROUND

Closed-loop small bowel obstruction (CL-SBO) can threaten the viability of the intestine by obstructing a bowel segment at two adjacent points. Prompt recognition and surgery are crucial.

AIM

To analyze the outcomes of patients who underwent surgery for CL-SBO and to evaluate clinical predictors.

METHODS

Patients who underwent surgery for suspected CL-BSO on computed tomography (CT) at a single center between 2013 and 2019 were evaluated retrospectively. Patients were divided into three groups by perioperative outcome, including viable bowel, reversible ischemia, and irreversible ischemia. Clinical and laboratorial variables at presentation were compared and postoperative outcomes were analyzed.

RESULTS

Of 148 patients with CL-SBO, 28 (19%) had a perioperative viable small bowel, 86 (58%) had reversible ischemia, and 34 (23%) had irreversible ischemia. Patients with a higher age had higher risk for perioperative irreversible ischemia [odds ratio (OR): 1.03, 95% confidence interval (CI): 0.99-1.06]. Patients with American Society of Anaesthesiologists (ASA) classification ≥ 3 had higher risk of perioperative irreversible ischemia compared to lower ASA classifications (OR: 3.76, 95%CI: 1.31-10.81). Eighty-six patients (58%) did not have elevated C-reactive protein (> 10 mg/L), and between-group differences were insignificant. Postoperative in-hospital stay was significantly longer for patients with irreversible ischemia (median 8 d, P = 0.001) than for those with reversible ischemia (median 6 d) or a viable bowel (median 5 d). Postoperative morbidity was significantly higher in patients with perioperative irreversible ischemia (45%, P = 0.043) compared with reversible ischemia (20%) and viable bowel (4%).

CONCLUSION

Older patients or those with higher ASA classification had an increased risk of irreversible ischemia in case of CL-SBO. After irreversible ischemia, postoperative morbidity was increased.

Prediction and management of strangulated bowel obstruction: a multi-dimensional model analysis

BACKGROUND

Distinguishing strangulated bowel obstruction (StBO) from simple bowel obstruction (SiBO) still poses a challenge for emergency surgeons. We aimed to construct a predictive model that could distinctly discriminate StBO from SiBO based on the degree of bowel ischemia.

METHODS

The patients diagnosed with intestinal obstruction were enrolled and divided into SiBO group and StBO group. Binary logistic regression was applied to identify independent risk factors, and then predictive models based on radiological and multi-dimensional models were constructed. Receiver operating characteristic (ROC) curves and the area under the curve (AUC) were calculated to assess the accuracy of the predicted models. Via stratification analysis, we validated the multi-dimensional model in the prediction of transmural necrosis both in the training set and validation set.

RESULTS

Of the 281 patients with SBO, 45 (16.0%) were found to have StBO, while 236(84.0%) with SiBO. The AUC of the radiological model was 0.706 (95%CI, 0.617-0.795). In the multivariate analysis, seven risk factors including pain duration ≤ 3 days (OR = 3.775), rebound tenderness (OR = 5.201), low-to-absent bowel sounds (OR = 5.006), low levels of potassium (OR = 3.696) and sodium (OR = 3.753), high levels of BUN (OR = 4.349), high radiological score (OR = 11.264) were identified. The AUC of the multi-dimensional model was 0.857(95%CI, 0.793-0.920). In the stratification analysis, the proportion of patients with transmural necrosis was significantly greater in the high-risk group (24%) than in the medium-risk group (3%). No transmural necrosis was found in the low-risk group. The AUC of the validation set was 0.910 (95%CI, 0.843-0.976). None of patients in the low-risk and medium-risk score group suffered with StBO. However, all patients with bowel ischemia (12%) and necrosis (24%) were resorted into high-risk score group.

CONCLUSION

The novel multi-dimensional model offers a useful tool for predicting StBO. Clinical management could be performed according to the multivariate score.

Predicting the Need for Surgery in Uncomplicated Adhesive Small Bowel Obstruction: A Scoring Tool

INTRODUCTION

Nonoperative treatment can be attempted for uncomplicated adhesive small bowel obstruction (ASBO), but carries a risk of delayed surgery. Highlighting initial parameters predicting risk of failure of nonoperative management would be of great interest.

METHODS

Patients initially managed conservatively for uncomplicated ASBO were retrospectively analyzed. Univariate and multivariate analysis were performed to identify predictive failure's factors. Based on the risk factors, a score was created and then prospectively validated in a different patients' population.

RESULTS

Among 171 patients included, 98 (57.3%) were successfully managed conservatively. In a multivariate analysis, three independent nonoperative management failure's factors were identified: Charlson Index ≥4 (P = 0.016), distal obstruction (P = 0.009), and maximum small bowel diameter over vertical abdominal diameter ratio >0.34 (P = 0.023). A score of two or three was associated with a risk of surgery of 51.4% or 70.3% in the retrospective analysis and 62.2% or 75% in the validation cohort, respectively.

CONCLUSIONS

This clinical-radiological score may help guide surgical decision-making in uncomplicated ASBO. A high score (≥2) was predictive of failure of nonoperative management. This tool could assist surgeons to determine who would benefit from early surgery.

Comparison of Clinical Outcomes and Safety Between Open and Laparoscopic Surgery for Adhesive Small Bowel Obstruction: A Propensity-Matched Analysis of a National Inpatient Database

Background: The effectiveness of laparoscopic surgery for adhesive small bowel obstruction (ASBO) remains unclear. We aimed to compare the outcomes and safety of open and laparoscopic surgeries for ASBO. Methods: In this retrospective study, we analyzed an inpatient database of 42 national university hospitals in Japan. Patients who underwent surgery for the first episode of ASBO between April 2013 and March 2018 were identified. Using the propensity score method, patients who underwent laparoscopic surgery were matched one-to-one with those who underwent open surgery. We investigated postoperative clinical outcomes, including morbidity, mortality, length of hospital stay (LOS), and recurrence. Results: Overall, 306 and 96 patients underwent open and laparoscopic surgery, respectively (96 propensity score-matched pairs). The incidence rates of postoperative morbidity, mortality, and recurrence were comparable between the two groups. Cox regression analysis revealed a hazard ratio (HR) of 1.020 (P = .959) for readmission due to ASBO in the laparoscopic surgery group relative to the open surgery group. Postoperative hospital stay was longer for open surgery than for laparoscopic surgery (13.0 days versus 10.0 days, P < .001). Cox regression analysis revealed that laparoscopic surgery was associated with earlier postoperative discharge compared with open surgery (HR 1.641, P = .002). Conclusions: The postoperative LOS was shorter with laparoscopic surgery than with open surgery for ASBO, but there were no differences between the procedures in other clinical outcomes. Laparoscopic surgery is suitable to treat patients with ASBO.

Time limit to rescue intestine with viability at risk caused by blood flow disruption in patients presenting with acute abdomen

Purpose

Early management is crucial for acute intestinal blood flow disorders; however, no published study has identified criteria for the time limit for blood flow resumption. This study specifically examines the time factors for avoiding intestinal resection.

Methods

The subjects of this retrospective cohort study were 125 consecutive patients who underwent emergency surgery for a confirmed diagnosis of intestinal strangulation (n = 86), incarceration (n = 27), or volvulus (n = 12), between January 2015 and March 2021. Intestinal resection was performed when intestinal irreversible changes had occurred even after ischemia was relieved surgically. We analyzed the relationship between the time from computed tomography (CT) imaging to the start of surgery (C-S time) and intestinal resection using the Kaplan–Meier method and calculated the estimated intestinal rescue rate. Patient background factors affecting intestinal resection were also examined.

Results

The time limit for achieving 80% intestinal rescue rate was 200 min in C-S time, and when this exceeded 300 min, the intestinal rescue rate dropped to less than 50%. Multivariate analysis identified the APACHE II score as a significant influencing factor.

Conclusion

A rapid transition from early diagnosis to early surgery is critical for patients with acute abdomen originating from intestinal blood flow disorders. The times from presentation at the hospital to surgery should be reduced further, especially for severe cases.

Machine Learning Based Prediction Model for Closed-Loop Small Bowel Obstruction Using Computed Tomography and Clinical Findings

PURPOSE

The aim of the study was to develop a prediction model for closed-loop small bowel obstruction integrating computed tomography (CT) and clinical findings.

METHODS

The radiology database and surgical reports from 2 suburban teaching hospitals were retrospectively reviewed for patients undergoing surgery for suspected closed-loop small bowel obstruction (CLSBO). Two observers independently reviewed the CT scans for the presence of imaging features of CLSBO, blinded to the surgically confirmed diagnosis and clinical parameters. Random forest analysis was used to train and validate a prediction model for CLSBO, by combining CT and clinical findings, after randomly splitting the sample into 80% training and 20% test subsets.

RESULTS

Surgery confirmed CLSBO in 185 of 223 patients with clinically suspected CLSBO. Age greater than 52 years showed 2.82 (95% confidence interval = 1.13-4.77) times higher risk for CLSBO (P = 0.021). Sensitivity/specificity of CT findings included proximal dilatation (97/5%), distal collapse (96/2%), mesenteric edema (94/5%), pneumatosis (1/100%), free air (1/98%), and portal venous gas (0/100%). The random forest model combining imaging/clinical findings yielded an area under receiver operating curve of 0.73 (95% confidence interval = 0.58-0.94), sensitivity of 0.72 (0.55-0.85), specificity of 0.8 (0.28-0.99), and accuracy of 0.73 (0.57-0.85). Prior surgery, age, lactate, whirl sign, U/C-shaped bowel configuration, and fecalization were the most important variables in predicting CLSBO.

CONCLUSIONS

A random forest model found clinical factors including prior surgery, age, lactate, and imaging factors including whirl sign, fecalization, and U/C-shaped bowel configuration are helpful in improving the prediction of CLSBO. Individual CT findings in CLSBO had either high sensitivity or specificity, suggesting that accurate diagnosis requires systematic assessment of all CT signs.

Point-of-care ultrasound-first for the evaluation of small bowel obstruction: National cost savings, length of stay reduction, and preventable radiation exposure

OBJECTIVES

Computed tomography (CT) has long been the gold standard in diagnosing patients with suspected small bowel obstruction (SBO). Recently, point-of-care ultrasound (POCUS) has demonstrated comparable test characteristics to CT imaging for the diagnosis of SBO. Our primary objective was to estimate the annual national cost saving impact of a POCUS-first approach for the evaluation of SBO. Our secondary objectives were to estimate the reduction in radiation exposure and emergency department (ED) length of stay (LOS).

METHODS

We created and ran 1000 trials of a Monte Carlo simulation. The study population included all patients presenting to the ED with abdominal pain who were diagnosed with SBO. Using this simulation, we modeled the national annual cost savings in averted advanced imaging from a POCUS-first approach for SBO. The model assumes that all patients who require surgery or have non-diagnostic POCUS exams undergo CT imaging. The model also conservatively assumes that a subset of patients with diagnostic POCUS exams undergo additional confirmatory CT imaging. We used the same Monte Carlo model to estimate the reduction in radiation exposure and total ED bed hours saved.

RESULTS

A POCUS-first approach for diagnosing SBO was estimated to save a mean (±SD) of $30.1 million (±8.9 million) by avoiding 143,000 (±31,000) CT scans. This resulted in a national cumulative decrease of 507,000 bed hours (±268,000) in ED LOS. The reduction in radiation exposure to patients could potentially prevent 195 (±56) excess annual cancer cases and 98 (±28) excess annual cancer deaths.

CONCLUSIONS

If adopted widely and used consistently, a POCUS-first algorithm for SBO could yield substantial national cost savings by averting advanced imaging, decreasing ED LOS, and reducing unnecessary radiation exposure in patients. Clinical decision tools are needed to better identify which patients would most benefit from CT imaging for SBO in the ED.

Evaluating suspected small bowel obstruction with the water-soluble contrast challenge

With optimized technique, the water-soluble contrast challenge is effective at triaging patients for operative vs non-operative management of suspected small bowel obstruction. Standardized study structure and interpretation guidelines aid in clinical efficacy and ease of use. Many tips and tricks exist regarding technique and interpretation, and their understanding may assist the interpreting radiologist. In the future, a CT-based water-soluble contrast challenge, utilizing oral contrast given as part of the initial CT examination, might allow for a more streamlined algorithm and provide more rapid results.

[Preoperative diagnosis of intestinal ischemia in small bowel obstruction. Only computed tomography? A multiple-center observational study]

OBJECTIVE

To evaluate the accuracy of clinical, laboratory and instrumental methods for diagnosis of intestinal ischemia following small bowel obstruction in emergency hospitals.

MATERIAL AND METHODS

Multiple-center observational retrospective study enrolled 158 consecutive patients with benign small bowel obstruction (SBO) treated at four hospitals between May 2017 and December 2019. The role of clinical, laboratory and instrumental diagnostic methods for intestinal ischemia was analyzed. We assessed the impact of CT and contrast-enhanced X-ray examination on survival of patients.

RESULTS

Laboratory parameters as criteria of ischemia following SBO were similar (leukocytosis >14·10⁹/l (p=1.0), serum lactate >2.0 mmol/l (p=0.28), heart rate >90/min (p=0.71) and fever (p=0.74)). The only laboratory indicator with significant differences was serum sodium. Decrease in leukocytosis over time was less common in patients with ischemia (25% vs. 61.3%, p=0.012). Univariate Kaplan-Meier analysis did not establish the effect of CT on survival (7.8% [95% CI 7.6-8.0] vs. 6.5% [95% CI 6.3-6.6], p=0.786). Logistic regression revealed 6.4-fold higher chance of accurate diagnosis (ischemia/non-ischemia) in case of CT-based conclusion of ischemia (95% CI 0.025-0.85). Univariate analysis showed that the use of water-soluble contrast for adhesive SBO was associated with lower mortality (4.1% [95% CI 4.0-4.2] vs. 14.3% [95% CI 13.7-14.9], p=0.032) without assessing the comparability of groups.

CONCLUSION

Routine laboratory tests were not specific for intestinal ischemia. Therefore, they should not be considered as the only criteria for surgical tactics in intestinal obstruction. Only CT showed acceptable diagnostic accuracy, and, apparently, only this method has real prospects for improving the quality of diagnosis due to technical support, training of surgeons and specialists for diagnosis.

[Surgical approach for small bowel obstruction in the Russian Federation. National survey of surgeons]

OBJECTIVE

To study surgical approach for small bowel obstruction (SBO) regarding national and international guidelines.

MATERIAL AND METHODS

Considering literature data, national and international guidelines and clinical practice, we have formulated 15 questions regarding surgical approach for non-neoplastic SBO. Questions were sent by e-mail to the members of the Russian Society of Surgeons. Survey lasted 60 days. We used the program that provides the respondent with the possibility of visual control of survey results. Survey results were compared with national and international clinical guidelines, Russian- and English-language scientific publications. Restriction of the number of votes >1 and identification of respondents were not provided by the program. There was no reward for survey. A summary is provided on the main issues.

RESULTS

There were 557 respondents (3.0% of surgeons in the Russian Federation). We obtained 481-620 answers for each question.

CONCLUSION

This study is a valuable tool for primary assessment of current surgical practice for SBO in the Russian Federation. Study design did not imply conclusions on the optimal strategy based on opinions of majority of respondents. According to our survey, a significant number of respondents use the treatment strategy that differ from clinical guidelines. Their approach is based on their own clinical experience and local guidelines for the treatment of SBO. Less than half of the answers matched to national clinical guidelines, less than 10% - to the WSES guidelines. Despite the formal coincidence of some statements in national clinical guidelines and English-language recommendations, significant nonconformities require scientific discussion.

Small bowel obstruction managed without hospital admission: A safe way to reduce both cost and time in the hospital?

BACKGROUND

Small bowel obstruction management has evolved to incorporate the Gastrografin challenge. We expanded its use to the emergency department observation unit, potentially avoiding hospital admission for highly select small bowel obstruction patients. We hypothesized that the emergency department observation unit small bowel obstruction protocol would reduce admissions, costs, and the total time spent in the hospital without compromising outcomes.

METHODS

We reviewed patients who presented with small bowel obstruction from January 2015 to December 2018. Patients deemed to require urgent surgical intervention were admitted directly and excluded. The emergency department observation unit small bowel obstruction guidelines were introduced in November 2016. Patients were divided into pre and postintervention groups based on this date. The postintervention group was further subclassified to examine the emergency department observation unit patients. Cost analysis for each patient was performed looking at number of charges, direct costs, indirect cost, and total costs during their admission.

RESULTS

In total, 125 patients were included (mean age 69 ± 14.3 years). The preintervention group (n = 62) and postintervention group (n = 63) had no significant difference in demographics. The postintervention group had a 51% (36.7 hours, P < .001) reduction in median duration of stay and a total cost reduction of 49% (P < .001). The emergency department observation unit subgroup (n = 46) median length of stay was 23.6 hours. The readmission rate was 16% preintervention compared to 8% in the postintervention group (P = .18).

CONCLUSION

Management of highly selected small bowel obstruction patients with the emergency department observation unit small bowel obstruction protocol was associated with decreased length of stay and total cost, without an increase in complications, surgical intervention, or readmissions.

Correlation of CT findings with intra-operative outcome in closed-loop small bowel obstruction (CL-SBO)

PURPOSE

To correlate CT-findings in patients with closed-loop small bowel obstruction (CL-SBO) with perioperative findings, to identify patients who require immediate surgical intervention. Secondary purpose was to substantiate the role of radiologists in predicting perioperative outcome.

METHODS

Data were retrospectively obtained from patients with surgically confirmed CL-SBO, between September 2013 and September 2019. Three radiologists reviewed CTs to assess defined CT features and predict patient outcome for bowel wall ischemia and necrosis using a likelihood score. Univariate statistical analyses were performed and diagnostic performance parameters and interobserver agreement were assessed for each feature.

RESULTS

Of 148 included patients, 28 (19%) intraoperatively had viable bowel and 120 (81%) had bowel wall ischemia or necrosis. Most CT characteristics, as well as the likelihood of ischemia and necrosis, found fair or moderate multirater agreement. Increased attenuation of bowel wall and mesenteric vessels on non-contrast-enhanced CT had a specificity for bowel ischemia or necrosis of 100% (sensitivity respectively 48% (p < 0.001) and 21% (p = 0.09)). Mesenteric edema had high sensitivity for ischemia or necrosis (90%), but specificity of only 26% (p < 0.001). For mesenteric fluid, sensitivity was 60% and specificity 57% (p = 0.004). Decreased enhancement of bowel wall in both arterial and PV-phase showed significant correlation, respectively a sensitivity of 58% and 42%, and specificity of 88% and 79% (both p < 0.001). Likelihood of both ischemia and necrosis were significantly correlated with perioperative outcome (p < 0.001).

CONCLUSION

CT findings concerning mesenteric and bowel wall changes, as well as radiologists' judgement of likelihood of ischemia and necrosis are significantly correlated with perioperative outcome of bowel wall ischemia and necrosis in patients with CL-SBO.

Pneumatosis intestinalis and portal venous gas in mechanical small bowel obstruction: Is it worrisome?

PURPOSE

The purpose of this study was to evaluate the clinical significance of pneumatosis intestinalis (PI) and portal venous gas (PVG) in patients with mechanical small bowel obstruction (SBO), using surgical findings or clinical follow-up as standard of reference.

MATERIALS AND METHODS

Fourteen patients with mechanical SBO associated with PI and PVG were retrospectively included. There were 7 men and 7 women with a mean age of 59±19 (SD) (range: 25-93 years). CT examinations were reviewed by two radiologists to confirm the diagnosis of mechanical SBO and make a description of PI. Interobserver agreement was calculated. The reference standard was intraoperative appearance of the bowel wall (10/14; 71%) or the recovery of a normal bowel function in patients who were managed conservatively (4/14; 29%).

RESULTS

Among the 10 patients who underwent surgery, a normal appearance of the bowel in association with PI on CT was found intraoperatively in 8/10 (80%) patients and a reversible ischemia in the remaining 2/10 (20%) patients. The four patients who were managed conservatively recovered normal bowel function. Two patients died within two weeks following SBO.

CONCLUSION

PI and PVG are not specific signs of bowel necrosis in mechanical SBO.

[Timing of surgery, intestinal ischemia and other real factors of mortality in acute adhesive small bowel obstruction: a multiple-center study]

OBJECTIVE

To analyze the factors of mortality in patients with acute adhesive small bowel obstruction (AASBO).

MATERIAL AND METHODS

A retrospective multiple-center study included 143 (85.6%) patients with AASBO out of 167 consecutive patients with small bowel obstruction for the period 2017-2019. All patients were divided into 3 groups: early surgery group (within 12 hours after admission), late surgery (after 12 hours), non-surgical management group. The outcomes and Kaplan-Meier survival were compared in all groups.

RESULTS

AASBO was resolved without surgery in 77 (53.8%) patients 19.6±17.4 (M=14) hours. In the Early Surgery Group (n=36), 24 patients had strangulation, 12 ones had non-strangulated bowel obstruction. In the Late Surgery Group (n=30), 15 patients had strangulation and 15 ones had no strangulation. Mortality was similar in early and late surgery (p=0.287), early and late surgery in patients with strangulation (p=0.940), early and late surgery in patients without strangulation (p=0.76). Patients died (n=10) after surgery only. Thus, postoperative mortality was 15.2%, overall mortality - 7.0%. All patients who underwent surgery after 24 hours (n=14) survived. Surgery increased the mortality risk compared to non-surgical management (95% CI 0 - 15.9, p=0.001). There was no effect of surgery time (more or less than 12 hours) on mortality for strangulation (95% CI 13.0-16.7, p 0.788) and non-strangulated obstruction (95% CI 29.4-5.4, p=0.061), bowel resection (95% CI 33.3-14.0, p=0.187), presence of bowel ischemia (95% CI 14.3-17.9, p 0.613).

CONCLUSION

Delayed surgery may be advisable in patients with AASBO and no obvious signs of strangulation due to less mortality.

Pearls, Pitfalls, and Conditions that Mimic Mesenteric Ischemia at CT

Acute mesenteric ischemia (AMI) is a life-threatening condition with a high mortality rate. The diagnosis of AMI is challenging because patient symptoms and laboratory test results are often nonspecific. A high degree of clinical and radiologic suspicion is required for accurate and timely diagnosis. CT angiography of the abdomen and pelvis is the first-line imaging test for suspected AMI and should be expedited. A systematic "inside-out" approach to interpreting CT angiographic images, beginning with the bowel lumen and proceeding outward to the bowel wall, mesentery, vasculature, and extraintestinal viscera, provides radiologists with a practical framework to improve detection and synthesis of imaging findings. The subtypes of AMI are arterial and venoocclusive disease, nonocclusive ischemia, and strangulating bowel obstruction; each may demonstrate specific imaging findings. Chronic mesenteric ischemia is more insidious at onset and almost always secondary to atherosclerosis. Potential pitfalls in the diagnosis of AMI include mistaking pneumatosis as a sign that is specific for AMI and not an imaging finding, misinterpretation of adynamic ileus as a benign finding, and pseudopneumatosis. Several enterocolitides can mimic AMI at CT angiography, such as inflammatory bowel disease, infections, angioedema, and radiation-induced enterocolitis. Awareness of pitfalls, conditions that mimic AMI, and potential distinguishing clinical and imaging features can assist radiologists in making an early and accurate diagnosis of AMI. ^©RSNA, 2020.

Vascular assessment in small bowel obstruction: can CT predict requirement for surgical intervention?

PURPOSE

Small bowel obstruction (SBO) is a common cause of emergency presentations for abdominal pain and can be complicated by mesenteric ischemia. Computed tomography is currently central to diagnosis and management planning. Currently accepted signs identify secondary effects of the root physiological insult, which is vascular obstruction. We hypothesized that with advancements in CT technology and reconstruction algorithms, we can now more closely interrogate the mesenteric vasculature for obstruction and more accurately predict the need for surgical intervention.

METHODS

We retrospectively audited the charts of all patients presenting with a clinical diagnosis of SBO at a single institution in a 12-month period. Two blinded consultant radiologists were then asked to analyze 3D MIP reconstruction CT scans for vascular obstruction in addition to any currently accepted signs of ischemia. Comparison between vascular cutoff and accepted current signs in the need for surgical intervention and the presence of any signs of ischemia in theater were recorded.

RESULTS

Vascular cutoff had a comparable, with a trend towards superiority, sensitivity and specificity and inter-observer agreement to currently accepted signs of ischemia. The absence of a cut off sign has an excellent negative predictive value for ischemia with only 2 (3.7%) patients demonstrating ischemia at surgery where the vascular cutoff sign was not seen to be present.

CONCLUSION

Interrogating vascular obstruction using 3D MIP reconstructions in small bowel obstruction may be a more sensitive and specific sign for prediction of surgical intervention, possibly occurring earlier in the obstruction pathway.

Risk factors of geriatrics index of comorbidity and MDCT findings for predicting mortality in patients with acute mesenteric ischemia due to superior mesenteric artery thromboembolism

OBJECTIVES

To identify risk factors of geriatrics index of comorbidity (GIC) and multidetector CT (MDCT) findings for predicting mortality in patients with acute mesenteric ischemia (AMI) due to superior mesenteric artery (SMA) thromboembolism.

METHODS

33 patients with AMI due to SMA thromboembolism underwent abdominal MDCT and angiography. Patients' comorbidities and MDCT findings of ischemic bowel/mesenteric injuries, regions of SMA involved by thromboembolism, and degrees of SMA stenosis were retrospectively reviewed. The comorbidities were classified into 1-4 levels according to GIC. The association of MDCT signs and GIC classification with mortality were analyzed. Diagnostic performances of risk factors associated with mortality were evaluated by receiver operating characteristic (ROC) curve analyses.

RESULTS

Eighteen patients (54.5%) died during hospitalization or follow-up, including one patient with class 1, two patients with class 2, eight patients with class 3, and seven patients with class 4 according to GIC. Three risk factors significantly associated with mortality were identified, including pneumatosis and/or portomesenteric venous gas (PPMVG) (p = 0.017), four regions of SMA involved by thromboembolism (region I + II + III + IV) (p = 0.036), and class 3 + 4 of comorbidities (p = 0.001). The sensitivity and specificity of PPMVG, region I + II + III + IV, class 3 + 4 of comorbidities, and the three risk factors combined for diagnosing mortality were 33.3 and 100%, 27.8 and 100%, 83.3 and 73.3%, and 88.9 and 73.3%, respectively. The areas under the ROC curve (AUC) of the three risk factors combined (0.88) and class 3 + 4 of comorbidities (0.78) were larger than that of PPMVG (0.67) and region I + II + III + IV (0.64). The mortality rate rose from 15.4% in patients without risk factor to 66.7%, 100%, and 100% in patients with one, two, and three factors, respectively.

CONCLUSION

Three risk factors for mortality were identified in patients with AMI due to SMA thromboembolism, including PPMVG and four regions of SMA involved by thromboembolism on MDCT images, and class 3 + 4 of comorbidities. Close monitoring of these risk factors could possibly lower the mortality.

ADVANCES IN KNOWLEDGE

Risk factors based on GIC and MDCT findings may be used to predict mortality in patients with AMI. Close monitoring of these risk factors could possibly lower the mortality.

Non-strangulated adhesive small bowel obstruction: CT findings predicting outcome of conservative treatment

OBJECTIVES

To clarify CT findings that predict outcome of conservative treatment in patients with non-strangulated adhesive small bowel obstruction (SBO).

METHODS

Unenhanced and contrast-enhanced abdominopelvic CT studies in 189 patients with adhesive SBO who had initial conservative treatment were reviewed. The CT findings included transition zone, beak signs, maximum bowel diameter, bowel diameter ratio, decreased bowel wall enhancement, increased unenhanced bowel wall attenuation, anterior parietal adhesion, bowel wall thickening, closed-loop obstruction, small bowel feces sign, whirl sign, mesenteric haziness, mesenteric, peritoneal fluid, and submucosal edema. These findings were statistically compared according to the success or failure of treatment.

RESULTS

Conservative treatment succeeded in 144 patients (76.2%) and failed in 45 patients (23.8%). At multivariate analysis, the lack of small bowel feces sign, focal, diffuse mesenteric haziness, and moderate amount of mesenteric fluid were independent findings predicting failure of conservative treatment, with odds ratios of 5.23, 5.5, 13.55, and 4.89, respectively. The presence of all significant findings showed a high specificity of 97.2% with positive likelihood ratio of 8.8. If CT scans showed none of the three significant findings, the negative predictive value was 97.6% and negative likelihood ratio was 0.08.

CONCLUSIONS

The lack of small bowel feces sign, focal, diffuse mesenteric haziness, and moderate amount of mesenteric fluid are independent CT findings predicting the failure of conservative treatment in patients with non-strangulated adhesive SBO. The combination of all CT findings suggests the need for surgery; absence of two or all CT findings should suggest an attempt for conservative treatment.

KEY POINTS

• To minimize delayed operation, it is important to identify non-strangulated adhesive small bowel obstruction patients in whom initial conservative treatment is likely to fail. • The lack of small bowel feces sign, the presence of mesenteric haziness, and a moderate amount of mesenteric fluid are independent factors predicting the failure of conservative treatment in patients with non-strangulated adhesive small bowel obstruction. • The combination of all three CT findings suggests the need for surgery; absence of two or all three CT findings should suggest an attempt for conservative treatment.

Adhesive Small Bowel Obstruction: Predictive Radiology to Improve Patient Management

Adhesive small bowel obstruction (SBO) remains one of the leading causes of emergency room visits and is still associated with high morbidity and mortality rates. Because the management of adhesive SBO has shifted from immediate surgery to nonoperative treatment in the absence of ischemia, it is crucial to rapidly detect or predict strangulation, which requires emergent surgery. CT is now established as the best imaging technique for the initial assessment of patients suspected of having adhesive SBO. CT helps confirm the diagnosis of mechanical SBO, locate the site of obstruction, establish the cause, and detect complications. This article is a review of the role of imaging in answering specific questions to help predict the management needs of each individual patient. It includes (a) an update on the best CT signs for predicting ischemia and a need for bowel resection; (b) a discussion of the CT features that help differentiate open-loop from closed-loop obstruction and a single adhesive band from matted adhesions and how these differences can influence the management; and (c) a review of the main CT predictors of the success or failure of nonoperative management in adhesive SBO.

Therapeutic effect of gastrografin and predictors of operative intervention in patients with adhesive small bowel obstruction: A randomized controlled study

Objectives

The study aimed to investigate the therapeutic effect of gastrografin for the conservative treatment of patients with adhesive small bowel obstruction (ASBO) and to identify the predictors of failure of conservative treatment in these patients.

Material and Methods

A randomized controlled trial was conducted on 52 patients with the diagnosis of ASBO in 2016. 100 mL of Gastrografin and 100 mL of 0.9% saline solution were gavaged through the nasogastric tube in the case (n= 26) and control (n= 26) groups, respectively. Patients in the case group were subjected to plain abdominal X-Rays at 12, 24 and 48 hours after administration of gastrografin.

Results

Fifty-two patients with a mean age of 57.6 ± 11.4 years (range 37-81), including 34 (65.4%) males were enrolled into the study. The number of patients who were successfully conservatively treated in the case group was 21 (80.8%), which was significantly higher than 13 (50%) in the control group (p= 0.04). Among these patients, mean hospital stay in the case group was 37.2 ± 5.5 hours (range 28-46), which was significantly shorter than 45.8 ± 9.2 hours (range 36-61) in the control group (p= 0.004). In multivariate analysis, more than one previous laparotomy was the only predictor of failure of conservative treatment (p <0.001).

Conclusion

Gastrografin may be associated with improvement of patients with ASBO. Lower number of previous laparotomies may be a predictor of successful conservative treatment of these patients.

Letting the Sun Set on Small Bowel Obstruction: Can a Simple Risk Score Tell Us When Nonoperative Care is Inappropriate?

Controversy remains as to which patients with small bowel obstruction (SBO) need immediate surgery and which may be managed conservatively. This study evaluated the ability of clinical risk factors to predict the failure of nonoperative management of SBO. The electronic medical record was used to identify all patients with SBO over one year. Clinical, laboratory, and imaging data were recorded. Univariate and multivariable analyses were performed to identify risk factors predicting need for surgery. Cox proportional hazards regression was used to identify risk factors that influence need and timing for surgery. Two hundred nineteen consecutive patients were included. Most patients did not have a prior history of SBO (75%), radiation therapy (92%), or cancer (70%). The majority had undergone previous abdominal or pelvic surgery (82%). Thirty-five per cent of patients ultimately underwent laparotomy. Univariate analysis showed that persistent abdominal pain, abdominal distention, nausea and vomiting, guarding, obstipation, elevated white blood cell count, fever present 48 hours after hospitalization, and high-grade obstruction on computed tomography (CT) scan were significant predictors of the need for surgery. Multivariable analysis revealed that persistent abdominal pain or distention (hazard ratio [HR], 3.04; P = 0.013), both persistent abdominal pain and distention (HR, 4.96; P < 0.001), fever at 48 hours (HR, 3.66; P = 0.038), and CT-determined high-grade obstruction (HR, 3.45; P = 0.017) independently predicted the need for surgery. Eighty-five per cent of patients with none of these four significant risk factors were successfully managed nonoperatively. Conversely, 92 per cent of patients with three or more risk factors required laparotomy. This analysis revealed four readily evaluable clinical parameters that may be used to predict the need for surgery in patients presenting with SBO: persistent abdominal pain, abdominal distention, fever at 48 hours, and CT findings of high-grade obstruction. These factors were combined into a predictive model that may of use in predicting failure of nonoperative SBO management. Early operation in these patients should decrease length of stay and diagnostic costs.

ACR Appropriateness Criteria® Suspected Small-Bowel Obstruction

Small-bowel obstruction is a common cause of abdominal pain and accounts for a significant proportion of hospital admissions. Radiologic imaging plays the key role in the diagnosis and management of small-bowel obstruction as neither patient presentation, the clinical examination, nor laboratory testing are sufficiently sensitive or specific enough to diagnose or guide management. This document focuses on the imaging evaluation of the two most commonly encountered clinical scenarios related to small-bowel obstruction: the acute presentation and the more indolent, low-grade, or intermittent presentation. This document hopes to clarify the appropriate utilization of the many imaging procedures that are available and commonly employed in these clinical settings. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

Variations in use of "water soluble contrast challenge" for small bowel obstruction among academic radiologists: results of a national survey

OBJECTIVE

To assess the frequency and indications for use of oral water-soluble contrast challenge as a diagnostic test for small bowel obstruction in four regions of the USA.

MATERIALS AND METHODS

We distributed a 9-question web-based survey to the abdominal section heads of academic radiology departments throughout the USA (N = 97). The questions pertained to use of water-soluble contrast for management of small bowel obstruction. Descriptive statistics and Fisher's exact tests were used for data analysis.

RESULTS

The overall response rate was 46%. Eighty percent of the responding hospitals had more than 500 beds in operation. Water-soluble contrast challenge was considered standard of care for management of non-operative small bowel obstruction in 60% of the responding radiology departments. The majority of the responding departments (41%) performed 2-8 contrast challenge studies per month on average. The most frequent indication for the study was distinguishing partial vs complete bowel obstruction. Eighty percent of the responding radiologists believed that the contrast challenge is useful for management of small bowel obstruction. Overall, there was no statistically significant difference in frequency and indication for use of water-soluble contrast challenge based on geographic location.

CONCLUSION

The water-soluble contrast challenge was considered standard of care for non-operative management of small bowel obstruction in majority of the academic radiology departments represented in this survey. Surgeons were referring clinicians in every case. The most common clinical indication for the study was distinguishing partial versus complete small bowel obstruction.

3D Vessel Image Reconstruction by MDCT for Surgical Indication and Timing of Strangulating Small Bowel Obstructions

BACKGROUND

Patients with strangulating small bowel obstructions (SBOs) can rapidly deteriorate, in condition; therefore, immediate and appropriate diagnosis is required. However, some cases of SBO are difficult to diagnose using axial computed tomography (CT) images alone. The impact of 3D vessel imaging for the diagnosis, surgical indication, and timing of strangulating SBOs was investigated, prospectively.

METHODS

Clinical data were collected for 111 strangulating SBOs and 48 simple SBOs from patients receiving surgical interventions from January 2009 to March 2018. The accuracy of preoperative diagnoses for the type of SBO was evaluated. Among 159 patients, 27 underwent contrast-enhanced CT imaging as well as prospectively reconstructed 3D vessel imaging of the superior mesenteric artery, vein, and branches. The concordance rate of operative findings and preoperative diagnoses of the type of SBO were compared between axial CT imaging alone and combination of axial and 3D vessel imaging.

RESULTS

Overall concordance rate of diagnosis for the type of SBO by axial imaging was 93.1% and that of strangulating and simple SBOs was 92.8% and 93.8%, respectively. Combined axial and 3D vessel imaging resulted in 100% accuracy of preoperative diagnoses for both types of SBO. In addition, abnormalities could be classified from 3D vessel images as central twists or peripheral twists, and deteriorated vascular flow could also be detected.

CONCLUSIONS

The combination of axial imaging and 3D vessel imaging can be used to accurately diagnose SBOs, and this imaging technique may be useful for determining the surgical indication and suitable timing of strangulating SBOs.

Management of Pediatric Adhesive Small Bowel Obstruction: Do Timing of Surgery and Age Matter?

BACKGROUND

Adhesive small bowel obstruction (ASBO) in children is generally managed with initial observation. However, no clear guidelines exist regarding indications to operate. Our purpose was to compare outcomes of ASBO management to determine whether timing of surgery and patient age should affect management.

MATERIALS AND METHODS

A retrospective review of children admitted to a tertiary care children's hospital for ASBO between 2011 and 2015 was performed. Data included demographics, imaging, operative findings, and clinical management, which were analyzed using χ² test, Fischer's exact test, t-test, analysis of variance, or logistic regression when appropriate.

RESULTS

We identified 258 admissions for 202 patients. Urgent operation was performed in 12% and the rest had nonoperative management (NOM), which was successful in 54%. Patients younger than 1 y of age were more likely to require operation (odds ratio 3.71, 95% confidence interval [CI] 1.69-8.15; P < 0.01), and patients with prior ASBO were less likely to require operation (odds ratio 0.51, 95% CI 0.31-0.84; P < 0.01). At presentation, fever was most common in patients who had urgent operation (22.3% versus failure of NOM 7.6% versus successful NOM 6.6%; P = 0.02), but there were no differences in leukocytosis or abdominal pain. Excluding urgent operations, bowel resection was more common when operation was delayed more than 48 h (32.6% versus 15.3%; P = 0.04).

CONCLUSIONS

In children with adhesive small bowel obstruction, NOM can be successful, but when failure is suspected, early operation before 48 h should be considered to avoid bowel loss, especially in children younger than 1 y of age.