The efficacy of helical CT in the diagnosis of small bowel obstruction

Imaging Signs for Determining Surgery Timing of Acute Intestinal Obstruction

We aimed to analyze the computed tomography (CT) imaging signs of bowel wall ischemia in patients with acute intestinal obstruction and construct an imaging prediction model to guide clinical treatment. The CT imaging signs of patients with acute intestinal obstruction diagnosed in our center in recent 6 years were collected for retrospective analysis. The etiology of intestinal obstruction and incidence rate of bowel wall ischemia were recorded, and the specific CT findings of bowel wall ischemia, including mesenteric edema, bowel wall thickening, and fish tooth sign, were analyzed. Among the 302 patients selected, 130 surgically treated patients were eligible for analysis. Bowel wall ischemia in acute intestinal obstruction showed an incidence rate of 14.90%, and the incidence rates of bowel wall ischemia in intra-abdominal hernia, intussusception, incarcerated external abdominal hernia, and volvulus were about 92.30%, 50%, 35.71%, 33.33%, and 12.59%, respectively. The incidence rate of bowel wall ischemia in simple adhesive intestinal obstruction was about 12.59%, and that in malignancy-induced intestinal obstruction was about 6.56%. Univariate analysis revealed 5 factors with statistical significance, including bowel wall thickening, mesenteric edema, bowel wall pneumatosis, ascites, and fish tooth sign. Multivariate logistic regression analysis indicated that fish tooth sign, bowel wall thickening, and mesenteric edema were able to predict bowel wall ischemia, and the corresponding partial regression coefficients were 2.164, 1.129, and 1.173, odds ratios (ORs) were 8.707, 3.093, and 3.232, sensitivity was 0.356, 0.400, and 0.844, and specificity was 0.859, 0.835, and 0.529, respectively. Imaging signs of bowel wall thickening, mesenteric edema, and fish tooth sign are valuable in predicting bowel wall ischemia, among which bowel wall thickening and mesenteric edema have relatively high specificity and fish tooth sign has a relatively high sensitivity. Furthermore, a fish tooth sign has the most favorable predictive value for bowel wall ischemia in acute intestinal obstruction, followed by bowel wall thickening and mesenteric edema.

Role of Gastrografin in Patients With Small Bowel Obstruction

Introduction

Gastrografin (GGF) is a radiopaque contrast medium commonly used for diagnostic examination of the gastrointestinal (GI) tract. Available evidence suggests it has therapeutic and predictive value in the management of adhesional small bowel obstruction (ASBO). Thus, we investigated the use of GGF amongst patients who had a small bowel obstruction and audited the practice in University Hospital, Ayr.

Methods

Initial retrospective data of patients who had gastrografin for small bowel obstruction were extracted from April 2015 to August 2019 and analysed. After our local presentation and on implementing a GGF protocol, we prospectively collected data from February to June 2020 to close our audit.

Results

GGF showed a comparable therapeutic effect on ASBO in both audit cycles (72.2%-66.7%). Approximately 50% of unresolved cases were operated within 24 hours of GGF administration in both cycles. GGF consistently demonstrated a therapeutic benefit in refractory faecal impaction (100% in both cycles) and postoperative ileus (≥ 80%). Early use of computed tomography (CT) (less than 24 hrs) did not confer any added advantage (82.5% v 61.5%), however, it helped in making an appropriate diagnosis and the subsequent early gastrografin usage (78.3% v 92.3%) in ASBO.

Conclusion

GGF serves a very good therapeutic purpose in resolving ASBO, refractory constipation, and in rare non-resolving cases of postoperative ileus. Early CT diagnosis of ASBO is advocated before the administration of gastrografin. Unsuccessful resolution after 24 hrs of GGF is an indication for operative intervention.

Diagnostic utility of CT for small bowel obstruction: Systematic review and meta-analysis

BACKGROUND

To perform a systematic review and meta-analysis evaluating the diagnostic performance of computed tomography (CT) for small bowel obstruction (SBO), including diagnostic accuracy, ischemia, predicting surgical intervention, etiology and transition point.

METHODS

PubMed/MEDLINE and related databases were searched for research articles published from their inception through August 2018. Findings were pooled using bivariate random-effects and summary receiver operating characteristic curve models. Meta-regression and subgroup analyses were performed to evaluate whether publication year, patient age, enhanced CT, slice thickness and pathogenesis affected classification accuracy.

RESULTS

In total, 45 studies with a total of 4004 patients were included in the analysis. The pooled sensitivity and specificity of CT for SBO were 91% (95% confidence interval [CI]: 84%, 95%) and 89% (95% CI: 81%, 94%), respectively, and there were no differences in the subgroup analyses of age, publication year, enhanced CT and slice thickness. For ischemia, the pooled sensitivity and specificity was 82% (95% CI: 67%, 91%) and 92% (95% CI: 86%, 95%), respectively. No difference was found between enhanced and unenhanced CT based on subgroup analysis; however, high sensitivity was found in adhesive SBO compared with routine causes (96% vs. 78%, P = 0.03). The pooled sensitivity and specificity for predicting surgical intervention were 87% and 73%, respectively. The accuracy for etiology of adhesions, hernia and tumor was 95%, 70% and 82%, respectively. In addition, the pooled sensitivity and specificity for transition point was 92% and 77%, respectively.

CONCLUSIONS

CT has considerable accuracy in diagnosis of SBO, ischemia, predicting surgical intervention, etiology and transition point.

Resolution of adhesive small bowel obstruction with a protocol based on Gastrografin administration

The use of Gastrografin may have a therapeutic effect on resolving adhesive small bowel obstruction.

Adhesive Small Bowel obstruction (ASBO) accounts for the majority of patients with small bowel obstruction. Most patients are managed conservatively; frequent admissions create a considerable burden. We sought to examine the adherence to the Bologna guidelines for the management of ASBO in a high volume tertiary center and whether or not Gastrografin had a therapeutic effect.

A comparison was made between an initial retrospective audit looking at ASBO and a prospective re-audit after applying standards derived from the Bologna guidelines. During re-audit it was found that more patients underwent conservative management and fewer patients had surgery as first line management. In the re-audit, those who had to undergo surgery within/after a period of 72h of conservative management were also fewer. Whether they were managed surgically primarily or after a period of conservative management, the average length of stay was also shorter. In comparison to the preliminary audit, there appeared to be no change in the way that medical history and physical examination was documented during the re-audit. However, there was a marked difference in the use of appropriate blood tests and CT scans.

Changes were made successfully following the initial audit results and have been implemented, thus closing the audit loop. This study shows that the use of Gastrografin has decreased the need for surgical intervention in a group of patients with small bowel obstruction.

Colostomy on CT and fluoroscopy: What the radiologist needs to know

Colostomies are commonly created in conjunction with colorectal surgery performed for both malignant and benign indications. Familiarity with the different types of colostomies and their normal imaging appearance will improve radiologic detection and characterization of colostomy complications. The radiologist plays a large role in assessment of colostomy patients either via fluoroscopic technique or multidetector computed tomography (CT) in order to help identify ostomy complications or to aid the surgeon prior to colostomy reversal. In this article, we will review: (1) the types of colostomies and indications for their creation; (2) the proper radiographic technique of ostomy evaluation; and (3) the potential complications of colostomies and their imaging manifestations.

Emergency Medicine Evaluation and Management of Small Bowel Obstruction: Evidence-Based Recommendations

BACKGROUND

Small bowel obstruction (SBO) is a commonly diagnosed disease in the emergency department (ED). Recent literature has evaluated the ED investigation and management of SBO.

OBJECTIVE

This review evaluates the ED investigation and management of adult SBO based on the current literature.

DISCUSSION

SBO is most commonly due to occlusion of the small intestine, resulting in fluid and gas accumulation. This may progress to mucosal ischemia, necrosis, and perforation. A variety of etiologies are present, but in adults, adhesions are the most common cause. Several classification systems are present. However, the most important distinction is complete vs. partial and complicated vs. simple obstruction, as complete complicated SBO more commonly requires surgical intervention. History and physical examination can vary, but the most reliable findings include prior abdominal surgery, history of constipation, abdominal distension, and abnormal bowel sounds. Signs of strangulation include fever, hypotension, diffuse abdominal pain, peritonitis, and several others. Diagnosis typically requires imaging, and though plain radiographs are often ordered, they cannot exclude the diagnosis. Computed tomography and ultrasound are reliable diagnostic methods. Management includes intravenous fluid resuscitation, analgesia, and determining need for operative vs. nonoperative therapy. Nasogastric tube is useful for patients with significant distension and vomiting by removing contents proximal to the site of obstruction. Surgery is needed for strangulation and those that fail nonoperative therapy. Surgical service evaluation and admission are recommended.

CONCLUSION

SBO is a common reason for admission from the ED. Knowledge of recent literature can optimize diagnosis and management.

Current management of adhesive small bowel obstruction

Small bowel obstruction is a common and significant surgical presentation. Approximately 30% of presentations will require surgery during admission. The great challenge of adhesive small bowel obstruction (ASBO) management is the early detection of silent intestinal ischaemia in patients initially deemed suitable for conservative therapy. Recent literature emphasizes the effectiveness of computed tomography enterography and water-soluble contrast studies in the management of ASBO. Low-volume undiluted water-soluble contrast has been shown to have both triage and therapeutic value in the management of ASBO. Their use has been demonstrated to reduce the need for surgery to below 20%. There has also been growing interest in clinicoradiological algorithms which aim to predict ischaemia early in the course of presentation. The aim of this review is to summarize the latest evidence and clarify previous uncertainties, specifically regarding the duration of conservative treatment, timing of contrast studies and the reliability of predictive algorithms. Based on this latest evidence, we have formulated a management protocol which aims to integrate these latest developments and formalize a strategy for best management in ASBO.

Laparoscopy in small bowel obstruction - current status - review

Introduction

Acute small bowel obstruction (SBO) is an urgent medical condition. Its diagnosis is based mainly on a clinical examination followed by confirmatory simple routine radiological examinations such as plain X-ray of the abdominal cavity or computed tomography (CT). However, a real surgical challenge is not a decision whether to perform a surgery, but a decision when and how to perform it.

Aim

To determine the place of laparoscopy in contemporary management of acute SBO based on the current literature.

Material and methods

A review of the literature based on the Medline database and including mainly the period of 2013–2017 was performed.

Conclusions

With regard to SBO, laparoscopy is a technique showing its advantages resulting from a minimally invasive approach. However, SBO is still a condition where the use of laparoscopy is limited mainly to selected cases such as SBO caused by single adhesions or foreign bodies. A basic limitation of using this technique is advanced and complicated SBO and lack of sufficient technical skills of the surgeon.

Accuracy of Plain Abdominal Radiography in the Differentiation between Small Bowel Obstruction and Small Bowel Ileus in Acute Abdomen Presenting to Emergency Department

Introduction

Our purpose was to evaluate whether plain abdominal radiography (PAR) could accurately differentiate between small bowel obstruction (SBO) and small bowel ileus (SBI) in an emergency setting. We also evaluated the value of known classic signs on the PAR for differentiating between SBO and SBI.

Methods

This retrospective study included 216 emergency room patients who had small bowel distension (maximal small bowel diameter ≥2.5 cm) on the PAR and who underwent successive abdominal computed tomography. One radiologist and one emergency physician retrospectively reviewed PAR in consensus, unaware of the patients' clinical data; they divided the patients into an SBO group and an SBI group according to the radiographic findings. Presence or numeric values of 10 radiographic signs were also recorded. Final diagnoses of SBO and SBI were established by a combined analysis of medical charts, surgical records, radiographic findings on abdominal computed tomography, and small bowel studies. The differential diagnoses based on PAR and the final diagnoses were compared, and the sensitivity and specificity of PAR were calculated. We also evaluated the differences among 10 radiographic signs between the final SBO and SBI groups.

Results

Sensitivity and specificity of PAR for SBO were 82.0% and 92.4%, respectively. Among the 10 radiographic signs, all except maximal colon diameter were statistically significant predictors on the final diagnosis.

Conclusions

PAR is an accurate and effective initial imaging modality for differentiating between SBO and SBI in an emergency setting, and most of the classic radiographic signs have a diagnostic value.

Early laparoscopic adhesiolysis for small bowel obstruction: retrospective study of main advantages

BACKGROUND

The problem of managing adhesional small bowel obstruction (ASBO) is still unsolved. A conservative medical attitude is privileged even if it is associated to a high rate of recurrences, while surgery is applied to cases showing no improvement after 48-72 h. Adhesiolysis via laparotomy has been the standard surgical management, but it causes other adhesions in a vicious circle. The aim of the study is to evaluate the advantages of early laparoscopic adhesiolysis as an alternative approach.

METHODS

From January 2010 to April 2017, 107 patients were admitted with a diagnosis of ASBO. Patients underwent medical treatment, early surgery, emergency surgery or delayed surgery after failure of medical treatment. A retrospective review and explorative statistical analysis were performed using graphical diagnostic plots, Mann-Whitney (MW) test, Kolmogorov-Smirnov (KS) test, exact binomial test, and χ ² test.

RESULTS

Medical treatment led to resolution in the 77.3% of cases, but patients exhibit much more recurrences than those in the surgical group (χ ² p < .001). They also show a longer fasting time (MW p = .027; KS p = .102), a doubled number of radiological exams (MW p < .001; KS p < .001), and more major complications than those in the early surgery group. Early surgery group is associated to shorter fasting time (MW p < .001; KS p < .001), much shorter hospital stay (MW p < .001; KS p = .002) and a smaller number of radiological exams (MW p = .005; KS p = .002) compared with delayed surgery group. The laparoscopic group shows significantly earlier regain of intestinal transit (MW p < .001; KS p = .002), shorter fasting time (MW p = .002; KS p = .008), reduced number of radiological exams (MW p = .003; KS p = .014), reduced hospital stay (MW p < .001; KS p = .005), and no more complications than the open surgery group.

CONCLUSIONS

Early laparoscopic surgery can be proposed as an effective alternative treatment for ASBO.

High-Density Free Fluid on Computed Tomography: a Predictor of Surgical Intervention in Patients with Adhesive Small Bowel Obstruction

BACKGROUND

Patients with adhesive small bowel obstruction (ASBO) often develop intraabdominal free fluid (IFF). While IFF is a finding on abdominopelvic computed tomography (CT) associated with the need for surgical intervention, many patients with IFF can be still managed non-operatively. A previous study suggested that a higher red blood cell count of IFF is highly predictive of strangulated ASBO. We hypothesized that radiodensity in IFF (Hounsfield unit (HU)) on CT would predict the need for surgical intervention.

STUDY DESIGN

Patients with clinicoradiological evidence of ASBO between January 2009 and December 2013 were identified. In patients with IFF > 3 cm² identified on CT, the HU was measured in the largest pocket of IFF. A sensitivity analysis was performed to determine a high-density HU threshold. The HU of patients who underwent therapeutic laparotomy was compared with those successfully discharged with non-operative management.

RESULTS

A total of 318 patients with ASBO (median age 52 years, 56.0 % male) were identified. Of 111 patients who had IFF on CT, 55.9 % underwent therapeutic laparotomy and 15.3 % required bowel resection. Radiodensity of IFF in the operative group was significantly higher than that in the non-operative group (18.2 vs. 7.0 HU, p < 0.01). Sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of high-density IFF (>10 HU) to predict the need for surgical intervention were 83.9, 65.3, 75.4, 76.2, and 75.6 %, respectively.

CONCLUSIONS

High-density IFF on CT was significantly associated with the need for surgical intervention in patients with ASBO. Prospective study to validate the predictive value of high-density IFF on CT will be warranted.

Review of small-bowel obstruction: the diagnosis and when to worry

This is a review of small-bowel obstruction written primarily for residents. The review focuses on radiography and computed tomography (CT) for diagnosing small-bowel obstruction and CT for determining complications. (©) RSNA, 2015.

Value of CT findings to predict surgical ischemia in small bowel obstruction: A systematic review and meta-analysis

PURPOSE

Our aim was to assess the diagnostic performance in determining strangulation in small bowel obstruction (SBO) for five CT findings commonly considered in published small bowel obstruction (SBO) management guidelines.

MATERIALS AND METHODS

Medical databases were searched for "bowel obstruction", "computed tomography", "strangulation", and related terms. Two reviewers independently selected articles for CT findings investigated with surgical or histological reference standards for strangulation. Bivariate random-effects meta-analytical methods were used.

RESULTS

A total of 768 patients, including 205 with strangulation from nine studies, were evaluated. The reduced bowel wall enhancement CT sign had the highest specificity (95 %, CI 75-99), with a positive LR of 11.07 (2.27-53.88) and DOR of 22.86 (4.99-104.61). The mesenteric fluid sign had the highest sensitivity (89 %, CI 75-96) with a negative LR of 0.16 (0.07-0.39) and a DOR of 13.9 (5.73-33.75). The bowel wall thickness had a sensitivity of 48 % (CI 41-54), a specificity of 83 % (CI 74-89), a positive LR of 2.84 (1.83-4.41) and a negative LR of 0.62 (0.53-0.72). The other CT findings had lower diagnostic performance.

CONCLUSION

Two CT findings should be used in clinical practice: reduced enhanced bowel wall is highly predictive of ischemia, and absence of mesenteric fluid is a reliable finding to rule out strangulation.

KEY POINTS

• Reduced bowel wall enhancement on CT increases the probability of strangulation 11-fold. • Absence of mesenteric fluid on CT decreases the probability of strangulation 6-fold. • The clinical reliability of other CT signs is doubtful for predicting strangulation.

A protocol for the management of adhesive small bowel obstruction

BACKGROUND

Differentiating between partial adhesive small bowel obstruction (aSBO) likely to resolve with medical management and complete obstruction requiring operative intervention remains elusive. We implemented a standardized protocol for the management of aSBO and reviewed our experience retrospectively.

METHODS

Patients with symptoms of aSBO were admitted for intravenous fluid resuscitation, bowel rest, nasogastric tube decompression, and abdominal examinations every 4 hours. Laboratory values and a computed tomography scan of the abdomen and pelvis with intravenous contrast were obtained. Patients with peritonitis or computed tomography scan findings suggesting bowel compromise were taken to the operating room for exploration following resuscitation. All other patients received 80 mL of Gastroview (GV) and 40 mL of sterile water via nasogastric tube. Abdominal plain films were obtained at 4, 8, 12, and 24 hours. If contrast did not reach the colon within 24 hours, then operative intervention was performed.

RESULTS

Over 1 year, 91 patients were admitted with aSBO. Sixty-three patients received GV, of whom 51% underwent surgery. Twenty-four patients went directly to the operating room because of clinical or imaging findings suggesting bowel ischemia. Average time to surgery was within 1 day for the no-GV group and 2 days for the GV group. Patients passing GV to the colon within 5 hours of administration had a 90% rate of resolution of obstruction. There was a direct relationship between the duration of time before passing GV to the colon and hospital length of stay (HLOS) (r = 0.459). Patients who received GV and did not require surgery had lower HLOS (3 days vs. 11 days, p < 0.0001).

CONCLUSION

The GV protocol facilitated early recognition of complete obstruction. Administration of GV had diagnostic and therapeutic value and did not increase HLOS, morbidity, or mortality.

LEVEL OF EVIDENCE

Therapeutic study, level V. Epidemiologic study, level V.

Bologna guidelines for diagnosis and management of adhesive small bowel obstruction (ASBO): 2013 update of the evidence-based guidelines from the world society of emergency surgery ASBO working group

Background

In 2013 Guidelines on diagnosis and management of ASBO have been revised and updated by the WSES Working Group on ASBO to develop current evidence-based algorithms and focus indications and safety of conservative treatment, timing of surgery and indications for laparoscopy.

Recommendations

In absence of signs of strangulation and history of persistent vomiting or combined CT-scan signs (free fluid, mesenteric edema, small-bowel feces sign, devascularization) patients with partial ASBO can be managed safely with NOM and tube decompression should be attempted. These patients are good candidates for Water-Soluble-Contrast-Medium (WSCM) with both diagnostic and therapeutic purposes. The radiologic appearance of WSCM in the colon within 24 hours from administration predicts resolution. WSCM maybe administered either orally or via NGT both immediately at admission or after failed conservative treatment for 48 hours. The use of WSCM is safe and reduces need for surgery, time to resolution and hospital stay.

NOM, in absence of signs of strangulation or peritonitis, can be prolonged up to 72 hours. After 72 hours of NOM without resolution, surgery is recommended.

Patients treated non-operatively have shorter hospital stay, but higher recurrence rate and shorter time to re-admission, although the risk of new surgically treated episodes of ASBO is unchanged. Risk factors for recurrences are age <40 years and matted adhesions. WSCM does not decrease recurrence rates or recurrences needing surgery.

Open surgery is often used for strangulating ASBO as well as after failed conservative management. In selected patients and with appropriate skills, laparoscopic approach is advisable using open access technique. Access in left upper quadrant or left flank is the safest and only completely obstructing adhesions should be identified and lysed with cold scissors. Laparoscopic adhesiolysis should be attempted preferably if first episode of SBO and/or anticipated single band. A low threshold for open conversion should be maintained.

Peritoneal adhesions should be prevented. Hyaluronic acid-carboxycellulose membrane and icodextrin decrease incidence of adhesions. Icodextrin may reduce the risk of re-obstruction. HA cannot reduce need of surgery.

Adhesions quantification and scoring maybe useful for achieving standardized assessment of adhesions severity and for further research in diagnosis and treatment of ASBO.

Adult small bowel obstruction

BACKGROUND

Small bowel obstruction (SBO) is a clinical condition that is often initially diagnosed and managed in the emergency department (ED). The high rates of potential complications that are associated with an SBO make it essential for the emergency physician (EP) to make a timely and accurate diagnosis.

OBJECTIVES

The primary objective was to perform a systematic review and meta-analysis of the history, physical examination, and imaging modalities associated with the diagnosis of SBO. The secondary objectives were to identify the prevalence of SBO in prospective ED-based studies of adult abdominal pain and to apply Pauker and Kassirer's threshold approach to clinical decision-making to the diagnosis and management of SBO.

METHODS

MEDLINE, EMBASE, major emergency medicine (EM) textbooks, and the bibliographies of selected articles were scanned for studies that assessed one or more components of the history, physical examination, or diagnostic imaging modalities used for the diagnosis of SBO. The selected articles underwent a quality assessment by two of the authors using the Quality Assessment of Diagnostic Accuracy Studies 2 (QUADAS-2) tool. Data used to compile sensitivities and specificities were obtained from these studies and a meta-analysis was performed on those that examined the same historical component, physical examination technique, or diagnostic test. Separate information on the prevalence and management of SBO was used in conjunction with the meta-analysis findings of computed tomography (CT) to determine the test and treatment threshold.

RESULTS

The prevalence of SBO in the ED was determined to be approximately 2% of all patients who present with abdominal pain. Having a previous history of abdominal surgery, constipation, abnormal bowel sounds, and/or abdominal distention on examination were the best history and physical examination predictors of SBO. X-ray was determined to be the least useful imaging modality for the diagnosis of SBO, with a pooled positive likelihood ratio (+LR) of 1.64 (95% confidence interval [CI] = 1.07 to 2.52). On the other hand, CT and magnetic resonance imaging (MRI) were both quite accurate in diagnosing SBO with +LRs of 3.6 (5- to 10-mm slices, 95% CI = 2.3 to 5.4) and 6.77 (95% CI = 2.13 to 21.55), respectively. Although limited to only a select number of studies, the use of ultrasound (US) was determined to be superior to all other imaging modalities, with a +LR of 14.1 (95% CI = 3.57 to 55.66) and a negative likelihood ratio (-LR) of 0.13 (95% CI = 0.08 to 0.20) for formal scans and a +LR of 9.55 (95% CI = 2.16 to 42.21) and a -LR of 0.04 (95% CI = 0.01 to 0.13) for beside scans. Using the CT results of the meta-analysis for the 5- to 10-mm slice subgroup as well as information on intravenous (IV) contrast reactions and nasogastric (NG) intubation management, the pretest probability threshold for further testing was determined to be 1.5%, and the pretest probability threshold for beginning treatment was determined to be 20.7%.

CONCLUSIONS

The potentially useful aspects of the history and physical examination were limited to a history of abdominal surgery, constipation, and the clinical examination findings of abnormal bowel sounds and abdominal distention. CT, MRI, and US are all adequate imaging modalities to make the diagnosis of SBO. Bedside US, which can be performed by EPs, had very good diagnostic accuracy and has the potential to play a larger role in the ED diagnosis of SBO. More ED-focused research into this area will be necessary to bring about this change.

Evaluation and management of small-bowel obstruction: an Eastern Association for the Surgery of Trauma practice management guideline

BACKGROUND

Small-bowel obstruction (SBO) represents as many as 16% of surgical admissions and more than 300,000 operations annually in the United States. The optimal strategies for the diagnosis and management of SBO continue to evolve secondary to advances in imaging techniques, critical care, and surgical techniques. This updated systematic literature review was developed by the Eastern Association for the Surgery of Trauma to provide up-to-date evidence-based recommendations for SBO.

METHODS

A search of the National Library of Medicine MEDLINE database was performed using PubMed interface for articles published from 2007 to 2011.

RESULTS

The search identified 53 new articles that were then combined with the 131 studies previously reviewed by the 2007 guidelines. The updated guidelines were then presented at the 2012 annual EAST meeting.

CONCLUSION

Level I evidence now exists to recommend the use of computed tomographic scan, especially multidetector computed tomography with multiplanar reconstructions, in the evaluation of patients with SBO because it can provide incremental clinically relevant information over plains films that may lead to changes in management. Patients with evidence of generalized peritonitis, other evidence of clinical deterioration, such as fever, leukocytosis, tachycardia, metabolic acidosis, and continuous pain, or patients with evidence of ischemia on imaging should undergo timely exploration. The remainder of patients can safely undergo initial nonoperative management for both partial and complete SBO. Water-soluble contrast studies should be considered in patients who do not clinically resolve after 48 to 72 hours for both diagnostic and potential therapeutic purposes. Laparoscopic treatment of SBO has been demonstrated to be a viable alternative to laparotomy in selected cases.

Oral traditional Chinese medication for adhesive small bowel obstruction

BACKGROUND

Small bowel obstruction (SBO) is one of the most common emergent complications of general surgery. Intra-abdominal adhesions are the leading cause of SBO. Because surgery can induce new adhesions, non-operative management is preferred in the absence of signs of peritonitis or strangulation. Oral traditional Chinese herbal medicine has long been used as a non-operative therapy to treat adhesive SBO in China. Many controlled trials have been conducted to investigate its therapeutic value in resolving adhesive SBO.

OBJECTIVES

The aim of this review was to assess the efficacy and safety of oral traditional Chinese medicine (TCM) for adhesive small bowel obstruction.

SEARCH METHODS

We searched the following databases, without regard to language or publishing restrictions: the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE, Chinese Biomedical Database (CBM), China National Knowledge Infrastructure/Chinese Academic Journals full-text Database (CNKI), and VIP (a full-text database of Chinese journals). The searches were conducted in November 2011.

SELECTION CRITERIA

Randomised controlled trials and quasi-randomised controlled trials comparing Chinese medicines administered orally, via the gastric canal, or both with a placebo or conventional therapy in participants diagnosed with adhesive SBO were considered. We also considered trials of TCM (oral administration, gastric tube perfusion, or both) plus conventional therapy compared with conventional therapy alone for patients with adhesive SBO. Studies addressing the safety and efficacy of oral traditional Chinese medicinal agents in the treatment of adhesive SBO were also considered.

DATA COLLECTION AND ANALYSIS

Two authors collected the data independently. We assessed the risk of bias according to the following methodological criteria: random sequence generation, allocation concealment, blinding, incomplete outcome data, selective outcome reporting and other sources of bias. Dichotomous data are presented as risk ratios (OR) and 95% confidence intervals (CI); continuous outcomes are presented as mean differences (MD) and 95% CIs. The data analyses were carried out using Review Manager 5.1. For cases in which necessary information was not reported in the paper, we contacted the primary authors for additional information.

MAIN RESULTS

Five randomised trials involving 664 participants were analysed. Five different herbal medicines were tested in these trials, including Huo-Xue-Tong-Fu decoction, Xiao-Cheng-Qi-Tang decoction, a combination of Xiao-Cheng-Qi-Tang and Si-Jun-Zi-Tang decoctions, Chang-Nian-Lian-Song-Jie-Tang decoction, and Fufang-Da-Cheng-Qi-Tang decoction. There were variations in the tested herbal compositions and methods of medicine administration. The main outcomes reported in the trials were effects on abdominal pain, abdominal distension, constipation defection, time of first defecation after treatment, and reoperation rate during the course of the disease. Secondary outcomes selected for this review were not available, including complications such as small bowel perfusion (bowel resection, system complications, and other possible complications), length of hospital stay, cost of hospitalisation, and time from admission to surgical intervention. The results of five trials showed that patients receiving TCM combined with conventional therapy seemed to have improved outcomes compared with patients receiving conventional treatment alone (OR 4.24, 95% CI 2.83 to 6.36).However, we cannot conclusively determine the efficacy of TCM in this review due to inadequate reporting, low methodological quality, and the prevalence of various biases in the reviewed studies. Furthermore, because none of the reviewed trials discussed adverse events, we could not evaluate the safety of TCM for adhesive SBO patients. All trials were conducted and published in China.

AUTHORS' CONCLUSIONS

Although many studies have assessed the use of TCM products for adhesive SBO, most were excluded from this review due to their methodological limitations. This systematic review did not find sufficient evidence to support the objective efficacy and safety of TCM for patients with adhesive SBO. The positive evidence should be interpreted with caution given the insufficient number of studies with large sample sizes, the absence of well-designed, high-quality trials, and the lack of safety information. Therefore, further studies with larger sample sizes and high-quality, randomised, and controlled trials are necessary to produce more accurate and meaningful data on the efficacy of Chinese herbal medicines for adhesive SBO.

Factors Predicting Need for and Delay in Surgery in Small Bowel Obstruction

Safe management of small bowel obstruction (SBO) depends on rapid diagnosis. The objective of this study was to determine factors predictive for operation and resulting in operative delay. A retrospective review was done of 1613 patients over 4 years (2003 to 2007) with International Classification of Diseases, 9th Revision codes for SBO. After excluding patients with incomplete clinical data, incorrectly coded, and age younger than 5 years, 872 patients were reviewed. Analysis was done for factors predictive for operation and factors associated with operative delay. Statistics was done using t test, Wilcoxon-rank-sum, and χ2. Four hundred ninety-four patients (56.6%) underwent surgery for SBO. Three hundred seventy-eight patients (43.4%) were managed nonoperatively. Of factors examined, younger patients ( P = 0.001), no previous operation ( P < 0.001), and absence of adhesive disease ( P < 0.001) were more likely to go to operation. Acquiring a computed tomographic scan ( P = 0.029) or radiograph ( P < 0.001) were the only factors that increased time to the operating room (OR). Increased time to the OR was associated with a higher incidence of bowel resection. With those with time to OR less than 24 hours, 39 of 325 patients(12%) had bowel resection versus time to OR greater than 24 hours, 23 of 80 patients (29%) required bowel resection. Identifying patients who may safely undergo nonoperative management remains difficult. Delay in operation for SBO places patients at higher risk for bowel resection.

Bowel obstruction and hernia

Bowel obstruction and abdominal hernia are commonly observed in patients seeking emergency care for abdominal pain. This article discusses bowel obstruction, adynamic ileus, acute colonic pseudo-obstruction, and abdominal hernias, with particular emphasis on the management of patients in the emergency department (ED). Although the diagnostic approach to bowel obstruction often requires imaging, abdominal hernia may be identified in most circumstances by history and physical examination alone. Urgent surgical consultation is indicated when there is a concern for bowel ischemia, strangulation, or complete obstruction. This article reviews an ED-based approach to the patient presenting with symptoms of bowel obstruction or hernia.

Strategies for diagnosis and treatment of small bowel obstruction

Small bowel obstruction, which is caused by a variety of etiological factors and mainly manifests as abdominal pain, vomiting and distension, is one of the most common acute abdomens. A rapid and accurate diagnosis of small bowel obstruction is needed to give reasonable and effective treatment to avoid its rapid deterioration. In this paper we discuss the strategies for diagnosis and treatment of small bowel obstruction through comparing different imaging methods for diagnosis of small bowel obstruction and reviewing the current situation of diagnosis and treatment of the disease in terms of pharmacotherapy, gastrointestinal decompression, and surgical intervention.

Bologna Guidelines for Diagnosis and Management of Adhesive Small Bowel Obstruction (ASBO): 2010 Evidence-Based Guidelines of the World Society of Emergency Surgery

Background

There is no consensus on diagnosis and management of ASBO. Initial conservative management is usually safe, however proper timing for discontinuing non operative treatment is still controversial. Open surgery or laparoscopy are used without standardized indications.

Methods

A panel of 13 international experts with interest and background in ASBO and peritoneal diseases, participated in a consensus conference during the 1^st International Congress of the World Society of Emergency Surgery and 9^th Peritoneum and Surgery Society meeting, in Bologna, July 1-3, 2010, for developing evidence-based recommendations for diagnosis and management of ASBO. Whenever was a lack of high-level evidence, the working group formulated guidelines by obtaining consensus.

Recommendations

In absence of signs of strangulation and history of persistent vomiting or combined CT scan signs (free fluid, mesenteric oedema, small bowel faeces sign, devascularized bowel) patients with partial ASBO can be managed safely with NOM and tube decompression (either with long or NG) should be attempted. These patients are good candidates for Water Soluble Contrast Medium (WSCM) with both diagnostic and therapeutic purposes. The appearance of water-soluble contrast in the colon on X-ray within 24 hours from administration predicts resolution. WSCM may be administered either orally or via NGT (50-150 ml) both immediately at admission or after an initial attempt of conservative treatment of 48 hours. The use of WSCM for ASBO is safe and reduces need for surgery, time to resolution and hospital stay.

NOM, in absence of signs of strangulation or peritonitis, can be prolonged up to 72 hours. After 72 hours of NOM without resolution surgery is recommended.

Patients treated non-operatively have shorter hospital stay, but higher recurrence rate and shorter time to re-admission, although the risk of new surgically treated episodes of ASBO is unchanged. Risk factors for recurrences are age <40 years and matted adhesions. WSCM does not affect recurrence rates or recurrences needing surgery when compared to traditional conservative treatment.

Open surgery is the preferred method for surgical treatment of strangulating ASBO as well as after failed conservative management. In selected patients and with appropriate skills, laparoscopic approach can be attempted using open access technique. Access in the left upper quadrant should be safe. Laparoscopic adhesiolysis should be attempted preferably in case of first episode of SBO and/or anticipated single band. A low threshold for open conversion should be maintained.

Peritoneal adhesions should be prevented. Hyaluronic acid-carboxycellulose membrane and icodextrin can reduce incidence of adhesions. Icodextrin may reduce the risk of re-obstruction. HA cannot reduce need of surgery.

Ischemia and infarction of the intestine related to obstruction

In the acute obstructive syndrome, beyond the evaluation of the morphologic findings of the intestine (e.g. dilation, air-fluid level, whirl sign, transition point), it is important to consider the pathophysiology of the bowel wall in order to better estimate the status of viability, the degree of the obstruction and the presence of the intestinal ischemic complications or infarction: the intestine is a dynamic system and the same pathological condition can appear in different forms, depending on the stage of disease. MDCT examination could be of help in differentiating various type and degree of disease of the intestinal ischemia correlated to obstruction.

Acute small bowel obstruction due to impacted bone: a case report

A 71-year-old man was admitted with features of intestinal obstruction. His past surgical history included an appendicectomy as a child and three laparotomies. A CT scan of the abdomen revealed a high attenuation foreign body impacted in the distal ileum, associated with small bowel obstruction. At laparotomy, a bone was removed from the terminal ileum.

Bowel obstruction: comparison between multidetector-row CT axial and coronal planes

Acute obstruction of bowel is a common reason for presentation to the emergency department. Causes of obstruction are multiple (tumorous, inflammatory, postoperative, or congenital), but the clinical presentation is usually not specific. The abdominal radiographs are sometimes inconclusive, and cause of obstruction is rarely detected. Computed tomography (CT) has been shown to be useful in revealing the site and the cause of obstruction. Although radiologists are skilled in the interpretation of CT scans in the axial plane, the development of multidetector-row CT coupled with fast reconstruction hardware and software has stimulated interest in viewing abdomen in coronal plane. In the evaluation of small bowel obstruction, coronal plane serves as a useful adjunct for the identification of the point of transition from dilated to decompressed bowel. On the other hand, in the evaluation of large bowel obstruction, coronal planes could replace axial images in the evaluation of the site and cause of obstruction, although the best values of confidence level in the diagnosis are reached when interpreting axial combined with coronal images.

CT of internal hernias

Computed tomography (CT) plays an important role in diagnosis of acute intestinal obstruction and planning of surgical treatment. Although internal hernias are uncommon, they may be included in the differential diagnosis in cases of intestinal obstruction, especially in the absence of a history of abdominal surgery or trauma. CT findings of internal hernias include evidence of small bowel obstruction (SBO); the most common manifestation of internal hernias is strangulating SBO, which occurs after closed-loop obstruction. Therefore, in patients suspected to have internal hernias, early surgical intervention may be indicated to reduce the high morbidity and mortality rates. In a study of 13 cases of internal hernias, nine different types of internal hernias were found and the surgical and radiologic findings were correlated. The following factors may be helpful in preoperative diagnosis of internal hernias with CT: (a) knowledge of the normal anatomy of the peritoneal cavity and the characteristic anatomic location of each type of internal hernia; (b) observation of a saclike mass or cluster of dilated small bowel loops at an abnormal anatomic location in the presence of SBO; and (c) observation of an engorged, stretched, and displaced mesenteric vascular pedicle and of converging vessels at the hernial orifice.

Imaging of small bowel-related complications following major abdominal surgery

To recognize and document the small bowel reactions following major abdominal surgery is an important key for a correct diagnosis. Usually, plain abdominal radiography is the initial imaging examination requested in the immediate postoperative period, whereas gastrointestinal contrast studies are used to look for specific complications. In some countries, especially in Europe, sonography is widely employed to evaluate any acute affection of the abdomen. CT is commonly used to assess postoperative abdominal complications; in our institution also CT enteroclysis is often performed, to provide additional important informations. Radiologist should be able to diagnose less common types of obstruction, such as afferent loop, closed loop, strangulating obstruction as well as internal hernia. This knowledge may assume a critical importance for surgeons to decide on therapy. In this article, we focus our attention on the imaging (particularly CT) in small bowel complications following abdominal surgery.

Post colon surgery complications: imaging findings

Several standardized types of colonic resections are available in the clinical practice. All of them may produce early and late complications. Diagnostic imaging plays a pivotal role in the recognition of post-operative colorectal complications and provides fundamental information for therapeutic planning. In this paper we review the imaging findings of early and late post-operative complications of colorectal surgery.

Computed tomography diagnosis of ischemia and complete obstruction in small bowel obstruction: a systematic review

This review was designed to describe the diagnostic performance of computed tomography (CT) in assessing bowel ischemia and complete obstruction in small bowel obstruction (SBO). A MEDLINE search (1966-2004) identified 15 studies dealing with the CT diagnosis of ischemia and complete obstruction in SBO. Ischemia was defined by operative findings, and complete obstruction was defined by enteroclysis or operative findings. Aggregated sensitivity, specificity, and positive and negative predictive values (PPV and NPV) were calculated. Eleven of 15 studies reported on the CT diagnosis of ischemia in SBO based on 743 patients. The aggregated performance characteristics of CT for ischemia in SBO were sensitivity of 83% (range, 63-100%), specificity of 92% (range, 61-100%), PPV of 79% (range, 69-100%), and NPV of 93% (range, 33.3-100%). Seven of 15 studies evaluated the CT classification of complete obstruction based on 408 patients. The aggregated performance characteristics of CT for complete obstruction were sensitivity of 92% (range, 81-100%), specificity of 93% (range, 68-100%), PPV of 91% (range, 84-100%), and NPV of 93% (range, 76-100%). This review demonstrates the high sensitivity of CT for ischemia in the setting of SBO and suggests that a CT scan finding of partial SBO is likely to reflect a clinical condition that will resolve without surgical intervention.