Flowmetry and spectrophotometry for the assessment of intestinal viability in horses with naturally occurring strangulating small intestinal lesions.

BACKGROUND: Ancillary diagnostic methods to enhance the accuracy of viability assessment have not been established for use in clinical practice. OBJECTIVES: To assess intestinal microperfusion measured by Laser Doppler Flowmetry and Spectrophotometry (LDFS) in naturally occurring small intestinal strangulations of different origins and to compare this between viable and non-viable segments. STUDY DESIGN: Prospective clinical trial. METHODS: Forty horses undergoing colic surgery for naturally occurring small intestinal strangulations were included. Tissue oxygen saturation (tSO2), haemoglobin (tHB) and blood flow (tBF) were determined by LDFS before and after release of the strangulation. Intestinal biopsies were taken in cases that underwent intestinal resection or intraoperative euthanasia and assessed using a semi-quantitative mucosal injury score (MIS). The LDFS measurements were compared between the different categories of strangulation causes and histopathological injury using parametric and non-parametric tests (p < 0.05). RESULTS: Strangulations by pedunculated lipomas had lower tBF (13.9 ± 18 arbitrary units [AU]) than epiploic foramen entrapments (65.2 ± 61 AU; CI -1.697 to -0.2498; p = 0.005). Segments with MIS > 5 showed lower tBF during strangulation than segments with MIS < 4 (mean difference 61.1 AU; CI -1.119 to -0.07361; p = 0.03). This did not differ significantly following release of strangulation. Furthermore, there was a positive correlation between the inflammatory cell count and tBF during strangulation (r 0.34; CI 0.01 to 0.60; p = 0.04). The tSO2 and tHB did not differ between the different categories of lesions or injury. MAIN LIMITATIONS: No biopsies could be taken from the intestinal segments that did not undergo resection. The duration of strangulation could not reliably be ascertained. CONCLUSIONS: Blood flow measurements in naturally occurring strangulating lesions show a varying degree of ischaemia in different causes of strangulation. Intestinal blood flow measurements prior to release of the strangulation could potentially contribute to the identification of mucosal injury, yet a high individual variability and other contributing factors need to be considered.

Development of a core outcome set to use in the research and assessment of malignant bowel obstruction: protocol for the RAMBO study.

INTRODUCTION: Studies regarding the management of malignant bowel obstruction (MBO) report conflicting findings. This is partly due to different outcome measures being used to evaluate severity of MBO and the response to treatments. Furthermore, current outcome measures focus mainly on measurable physiological parameters which may not correlate strongly with patient-defined quality of life. The development of core outcome sets allows a consistent approach to evaluating clinical conditions taking into consideration patient, healthcare professional and researcher viewpoints. It follows an internationally recognised standard methodology. We present a protocol for the development of a core outcome set for Research and Assessment of MBO (RAMBO). METHODS: RAMBO is a multicentre study, comprising of four phases: a systematic review to examine current scope of outcome measures associated with MBO (phase I). Interviews with patients, companions and healthcare professionals will explore priorities and preferences for care and outcomes (phase II). An expert panel meeting will collate the findings into a set of outcomes (phase III), refined by consensus through a Delphi survey with key stakeholders (phase IV). The final set of outcomes will be ratified at a consensus meeting. Each step will actively include patient partners. Thematic analysis and descriptive statistics will be used to analyse qualitative and quantitative data, respectively. ETHICS AND DISSEMINATION: Ethical approval was obtained (Wales REC 5, REF: 19/LO/1876). Study participants and relevant stakeholders will be updated with newsletters and a lay summary at the end of the study. Abstracts will be submitted to national and international conferences, result papers will be submitted to peer-reviewed, open access journals. TRIAL AND PROSPERO REGISTRATION NUMBERS: Core Outcome Measures in Effectiveness Trials (1402); Systematic Literature Review (CRD42019150648); Rapid Review (CRD42020176393).

Experimental Models of Partial Intestinal Obstruction in Young Mice: Establishment, and Evaluation.

BACKGROUND: Partial small bowel obstruction (SBO) is a common, potentially hazardous, surgical entity caused by numerous factors in humans. A number of techniques have been reported as efficient to simulate partial SBO in murine models. However, there is little data concerning their long-term survival. Our study presents a novel technique and evaluates its long-term efficiency compared with other commonly used techniques. MATERIALS AND METHODS: Sixty C57BL/6 mice aged 6 to 8 wk were randomly divided into five intervention groups: ligation, intestinal ring, partial ligation, microclips, and the novel triple suture technique. The ring groups were subdivided into narrow, medium, and wide ring and partial ligation groups were subdivided at 1/3, 1/2, and 2/3 of the lumen. Survival cutoff time was set at 4 wk. Animals were then euthanized and small bowel muscle layer thickness was histopathologically evaluated. RESULTS: None of the animals of the ligation and the ring groups reached the cutoff survival time. The mortality rate of the partial ligation and the microclips groups at the 4-week period were 33.3% and 0%, respectively. However, elimination of the performed intervention was revealed at the time of euthanasia and no alterations of the muscle layer were revealed at histopathology. The "triple suture" group had a survival rate of 90% until euthanasia and the sutures were apparent in all cases. Macroscopic evaluation showed small to mild proximal lumen dilatation in 6 of 10 animals. Histopathological evaluation of the specimens confirmed the partial obstruction. CONCLUSIONS: The "triple suture" technique is a new, robust, reliable, and inexpensive technique for experimental long-standing partial SBO, with very low mortality.

Optimizing the Care of Malignant Bowel Obstruction in Patients With Advanced Gynecologic Cancer.

PURPOSE: Malignant bowel obstruction (MBO) is a common and distressing complication in women with advanced gynecologic cancer. A pilot, interprofessional MBO program was launched in 2016 at a large Canadian tertiary cancer center to integrate these patients' complex care needs across multiple disciplines and support women with MBO. METHOD: Retrospective analysis to evaluate the outcomes of women with advanced gynecologic cancer who were admitted to hospital because of MBO, before (2014 to 2016: baseline group) and after (2016 to 2018) implementation of the MBO program. RESULTS: Of the 169 women evaluated, 106 and 63 were in the baseline group and MBO program group, respectively. Most had ovarian cancer (n = 124; 73%) and had small-bowel obstruction (n = 131; 78%). There was a significantly shorter cumulative hospital length of stay (LOSsum) within the first 60 days of MBO diagnosis in the MBO program group compared with the baseline group (13 v 22 days, respectively; adjusted P = .006). The median overall survival for women treated in the MBO program was also significantly longer compared with the baseline group (243 v 99 days, respectively; adjusted P = .002). Using the interprofessional MBO care platform, a greater proportion of patients received palliative chemotherapy (83% v 56%) and less surgery (11% v 21%) in the MBO program group than in the baseline group, respectively. A subgroup of women (n = 11) received total parenteral nutrition for longer than 6 months. CONCLUSION: Implementation of a comprehensive, interprofessional MBO program significantly affects patient care and may improve outcomes. Unique to this MBO program is an integrated outpatient model of care and education that empowers patients to recognize MBO symptoms for early intervention.

Assessment of Crohn's disease-associated small bowel strictures and fibrosis on cross-sectional imaging: a systematic review.

Patients with Crohn's disease commonly develop ileal and less commonly colonic strictures, containing various degrees of inflammation and fibrosis. While predominantly inflammatory strictures may benefit from a medical anti-inflammatory treatment, predominantly fibrotic strictures currently require endoscopic balloon dilation or surgery. Therefore, differentiation of the main components of a stricturing lesion is key for defining the therapeutic management. The role of endoscopy to diagnose the nature of strictures is limited by the superficial inspection of the intestinal mucosa, the lack of depth of mucosal biopsies and by the risk of sampling error due to a heterogeneous distribution of inflammation and fibrosis within a stricturing lesion. These limitations may be in part overcome by cross-sectional imaging techniques such as ultrasound, CT and MRI, allowing for a full thickness evaluation of the bowel wall and associated abnormalities. This systematic literature review provides a comprehensive summary of currently used radiologic definitions of strictures. It discusses, by assessing only manuscripts with histopathology as a gold standard, the accuracy for diagnosis of the respective modalities as well as their capability to characterise strictures in terms of inflammation and fibrosis. Definitions for strictures on cross-sectional imaging are heterogeneous; however, accuracy for stricture diagnosis is very high. Although conventional cross-sectional imaging techniques have been reported to distinguish inflammation from fibrosis and grade their severity, they are not sufficiently accurate for use in routine clinical practice. Finally, we present recent consensus recommendations and highlight experimental techniques that may overcome the limitations of current technologies.

Assessment of Strangulation in Adhesive Small Bowel Obstruction on the Basis of Combined CT Findings: Implications for Clinical Care.

Purpose To determine which computed tomography (CT) findings or combinations of findings can help to accurately identify strangulation in adhesive small bowel obstruction (SBO). Materials and Methods Contrast agent-enhanced CT findings in a cohort of 256 patients consecutively admitted for adhesive SBO, with a delay of less than 24 hours between CT and surgery for the operated patients, were reviewed independently by two radiologists, with consensus by a third, to assess CT findings commonly associated with strangulation. The reference standard for strangulation was surgery. Univariate and multivariate analyses were performed to identify predictors of strangulation in the entire cohort and to identify predictors of the need for surgical resection in the subgroup of patients with strangulation. A CT score was obtained and diagnostic performances of different combined CT findings were calculated. Results In this study, 105 patients (41.0%; 105 of 256) underwent a surgical procedure, 62 of whom were found to have strangulation (59.0%; 62 of 105), whereas 151 patients (59.0%; 151 of 256) improved with medical care. Three CT findings were significantly associated with strangulation in the multivariate analysis: reduced bowel wall enhancement (odds ratio, 7.8; 95% confidence interval [CI]: 2.6, 23.5), diffuse mesenteric haziness (odds ratio, 6.1; 95% CI: 2.5, 15.2), and a closed-loop mechanism (odds ratio, 6.5; 95% CI: 2.8, 15.5). The model combining these three features had an area under the curve of 0.91 (95% CI: 0.86, 0.96) and a high negative predictive value (97%; 95% CI: 93%, 99%). Positive likelihood ratios were high when two or three of these CT findings were combined (positive likelihood ratios, 14.7 [95% CI: 7.1, 30.4] and 43.8 (95% CI: 14.2, 135.2], respectively). Among the strangulated cases, reduced bowel wall enhancement (odds ratio, 3.9; 95% CI: 1.3, 12) and mesenteric fluid (odds ratio, 3.6; 95% CI: 1.0, 12.8) were predictive of resection. Conclusion A score that combines three CT findings (reduced bowel wall enhancement, a closed-loop mechanism, and diffuse mesenteric haziness) can accurately predict strangulation in adhesive SBO. © RSNA, 2017 Online supplemental material is available for this article.

Value in palliative cancer surgery: A critical assessment.

Emergency operations are associated with increased morbidity, mortality, and cost compared to elective operations. Palliative and emergent surgery for patients with advanced malignancies is associated with additional risk and remains controversial. Emergent or palliative interventions can be broadly categorized according to indication. Tumor related complications (bleeding, obstruction, or perforation) merit specific consideration, as do specific presentations such as pneumoperitoneum, pneumatosis intestinalis, or peritonitis from other causes that may arise during active therapy for malignancies. Although nonoperative, endoscopic, and interventional treatment modalities are frequently available, surgery remains the only effective therapy in selected situations such as small intestinal obstruction and tumor perforation. Selection of patients for surgery requires consideration of factors including overall prognosis, performance status, and patients' priorities. Selection and risk assessment tools underscore the limited capacity of patients' with higher risk features for durable recovery but do not supplant nuanced clinical judgment. J. Surg. Oncol. 2016;114:311-315. © 2016 Wiley Periodicals, Inc.

Techniques and principles of endoscopic treatment of benign gastrointestinal strictures.

PURPOSE OF REVIEW: The fundamental goal of treating any stenosis is luminal enlargement to ameliorate the underlying obstructive symptoms. Symptoms depend on the etiology and the site of the stricture and may include dysphagia, nausea and vomiting, abdominal pain, obstipation, or frank bowel obstruction. This article compares the various current technologies available for the treatment of gastrointestinal stenoses with regard to ease and site of application, patient tolerance, safety and efficacy data, and cost-benefit ratio. RECENT FINDINGS: Recent studies indicate that gastrointestinal dilation and stenting have evolved to a point at which in many if not most situations they can be the first line therapy and potentially the final therapy needed to treat the underlying condition. SUMMARY: Following techniques and principles in the management of gastrointestinal strictures would allow for the well tolerated and effective treatment of most patients with the tools currently available today.

Assessment of Obstructive Defecation by High-Resolution Anorectal Manometry Compared With Magnetic Resonance Defecography.

BACKGROUND & AIMS: Patients with obstructive defecation have abnormalities of anorectal function and/or structure. Conventional anorectal manometry (ARM) can identify abnormal function and behavior (dyssynergia); however, agreement between manometry and defecography is only fair. High-resolution (HR)-ARM may improve diagnostic agreement by differentiating pressure effects caused by dyssynergia and obstruction. We compared HR-ARM findings with magnetic resonance (MR) defecography in the clinical assessment of patients with symptoms of obstructive defecation defined by Rome III criteria. METHODS: HR-ARM (Manoscan AR 360; Given Imaging, Yoqeam, Israel) assessed anal sphincter function and pressure during simulated defecation. Abnormal manometric findings were classified according to the Rao system and compared with MR defecography as the reference standard. RESULTS: A total of 188 consecutive patients (155 women; age, 19-93 y) with obstructive defecation underwent a full investigation. Compared with patients with dyssynergia on MR imaging (n = 66), patients with structural pathology (n = 87) had lower resting (P < .003) and squeeze pressures (P < .011), but a higher rectoanal pressure gradient (P < .0001) on HR-ARM. High intrarectal pressure with a steep, positive pressure gradient consistent with outlet obstruction on HR-ARM was present in 24 patients with intra-anal intussusception on MR imaging. This pattern was not observed in other patients. Interobserver agreement was substantial for HR-ARM diagnoses (κ = 0.67; 95% confidence interval, 0.559-0.779). Diagnostic accuracy for dyssynergia was 82% compared with MR imaging (sensitivity, 77% [51 of 66]; specificity, 85% [104 of 122]). CONCLUSIONS: The diagnostic agreement between anorectal HR-ARM and MR defecography is high and pressure measurements accurately identify recto-anal dyssynergia and intra-anal outlet obstruction by structural pathology as causes of obstructive defecation.

[IMPROVEMENT AND CHOICE OF COLOSTOMY METHOD IN THE TREATMENT OF PATIENTS, SUFFERING AN ACUTE OBTURATIVE IMPASSABILITY OF LARGE BOWEL].

Colostomy was done in 49 patients, suffering an acute obturative impassability of large bowel (AOILB). In 28 patients (1st group) colostomy was conducted in accordance to standard method; in 21 (2nd group)--in accordance to the method, proposed by us. Application of the method proposed for surgical treatment of AOILB have guaranteed a reduction of postoperative paracolostomal complications rate in 6.8 times, of postoperative lethality--in 2.2 times, duration of the patient stationary treatment--in 1.4 times, the rate of dressings and the dressing material expanses--in 10 times.

Strain assessment in surgically resected inflammatory and neoplastic bowel lesions.

PURPOSE: To investigate whether ultrasound-based strain imaging can discriminate between colorectal adenocarcinomas and stenotic Crohn's lesions in newly resected surgical specimens. MATERIALS AND METHODS: Resected surgical specimens from 27 patients electively operated for colorectal tumors or stenotic lesions from Crohn's disease were prospectively examined with ultrasonography using a Hitachi HV 900 US scanner with real-time elastography (RTE). Three different methods were applied to assess tissue strain: A four-level categorical visual classification, a continuous visual analog scale (VAS, 0 - 100) and a strain ratio (SR) measurement between the lesion and surrounding reference tissue. The imaged sections were marked and subsequently examined by a pathologist. Results from RTE were evaluated according to diagnosis, degree of fibrosis, inflammatory parameters, tumor stage and grade. RESULTS: 16 sections from Crohn's lesions, 18 sections from adenocarcinomas and 4 sections from adenomas were examined. Both adenocarcinomas and Crohn's lesions were found to be harder than the surrounding tissue, but they could not be discriminated from each other by any of the strain imaging evaluation methods. All adenocarcinomas had significantly higher strain ratios than adenomas. The categorical classification differentiated poorly between Crohn's lesions, adenocarcinomas and adenomas. Categorical evaluation and VAS score showed fair interobserver agreement. SR measurements provided semi-quantitative strain data and added improved information about elasticity properties, despite substantial intra-observer variation. CONCLUSION: Sonoelastography with SR measurements and visual evaluation of strain differences could not differentiate stenotic Crohn's lesions from adenocarcinomas in resected bowel specimens. A small number of adenomas were found to be significantly softer than adenocarcinomas using the same evaluation methods. The tumor stage or grade did not have a significant impact on the elastography results.

Prospective comparison of computed tomography enterography and magnetic resonance enterography for assessment of disease activity and complications in ileocolonic Crohn's disease.

BACKGROUND: Studies comparing magnetic resonance enterography (MRE) and computerized tomography enterography (CTE) for Crohn's disease (CD) are scarce. METHODS: The aim of this study was to prospectively compare the sensitivity, specificity, and accuracy of abdominal MRE and CTE to assess disease activity and complications (fistulas, strictures) in ileocolonic CD. A total of 44 patients (23 male; 21 female; mean age 44) with ileocolonic CD underwent both MR and CT in a short time interval (mean 5 days). A 16-slice CT with intravenous contrast and an MRI with oral and paramagnetic intravenous contrast were performed. Ileocolonoscopy was used as the reference standard. Sensitivity values of CT and MR for detection of extraenteric signs of disease were compared with the McNemar test, with results of imaging studies, surgery, and physical examination as reference standards. RESULTS: No significant differences in sensitivity, specificity, and accuracy were observed between MRE and CTE regarding the following parameters at the patient level: localization of CD (P = 1.0), bowel wall thickening (P = 1.0), bowel wall enhancement (P = 1.0), enteroenteric fistulas (P = 0.08), detection of abdominal nodes (P = 1.0), and perivisceral fat enhancement (P = 0.31). MR was significantly superior compared to CT in detecting strictures (P = 0.04). Per segment analysis showed that MRE was significantly superior to CTE in detecting ileal wall enhancement (P = 0.02). CONCLUSIONS: MR and CT are equally accurate to assess disease activity and bowel damage in CD. MR may be superior to CT in detecting intestinal strictures and ileal wall enhancement. MR may represent an alternative technique to CT in assessing ileocolonic CD.

A new rat model of prenatal bowel obstruction: development and early assessment.

PURPOSE: Although intestinal motility disorders often complicate the postoperative surgical management of newborns with congenital intestinal atresia, their pathogenesis remains unclear. Animal models of prenatal intestinal obstruction have been mainly developed in the lamb and the chicken. Despite new insights brought by these models, they have one or more limitations, such as high fetal mortality rates, high costs, long gestation periods, and an insufficient number of fetuses per litter. Moreover, some species are phylogenetically distant from mammals. METHODS: We developed a reproducible model of prenatal intestinal obstruction in the rat to study the histologic changes induced by the obstruction. We report, the technical devices and the first assessment of this atresia model in a didactic way to allow other researchers to easily reproduce the model. RESULTS: Prenatal intestinal obstructions in this study fulfilled all the macroscopic and histologic criteria usually listed by other models of prenatal intestinal obstruction that have been developed in other species. Furthermore with our model, we obtained a high success rate at a low cost. CONCLUSIONS: We presented in this study a reproducible model of prenatal intestinal obstruction in the rat with the macroscopical and histologic features of prenatal intestinal obstruction.

Stents and stentability: treatment for malignant bowel obstruction.

Colonic stents offer a palliative treatment for patients with malignant bowel obstruction otherwise requiring surgery and possible stoma, or as a bridge to surgery for potentially curative malignant disease. This article reviews the indications, risks and benefits of stent insertion.

Comparison of colonic stenting and open surgery for malignant large bowel obstruction.

BACKGROUND: Colonic stents potentially offer effective palliation for those with bowel obstruction attributable to incurable malignancy, and a "bridge to surgery" for those in whom emergency surgery would necessitate a stoma. The current study compared the outcomes of stents and open surgery in the management of malignant large bowel obstruction. METHODS: A literature search of the Medline, Ovid, Embase and Cochrane databases was performed to identify comparative studies reporting outcomes on colonic stenting and surgery for large bowel obstruction. Random effects meta-analytical techniques were applied to identify differences in outcomes between the two groups. Sensitivity analysis of high quality studies, those reporting on more than 35 patients, those solely concerning colorectal cancer and studies performing intention to treat analysis was undertaken to evaluate the study heterogeneity. RESULTS: A total of 10 studies satisfied the criteria for inclusion, with outcomes reported for 451 patients. Stent insertion was attempted for 244 patients (54.1%), and proved successful for 226 (92.6%). The length of hospital stay was shorter by 7.72 days in the stent group (p < 0.001), which also had lower mortality (p = 0.03) and fewer medical complications (p < 0.001). Stoma formation at any point during management was significantly lower than in the stent group (odds ratio, 0.02; p < 0.001), and "bridging to surgery" did not adversely influence survival. CONCLUSIONS: Colonic stenting offers effective palliation for malignant bowel obstruction, with short lengths of hospital stay and a low rate for stoma formation, but data on quality of life and economic evaluation are limited. There is no evidence of differences in long-term survival between those who have stents followed by subsequent resection and those undergoing emergency bowel resection.

Dynamic magnetic resonance imaging defecography: a diagnostic alternative in the assessment of pelvic floor disorders in proctology.

PURPOSE: Standard diagnostic proctologic procedures in the assessment of pelvic floor disorders include clinical evaluation and endoscopy. Particular aspects of combined pelvic floor disorders, especially those involving more than one pelvic compartment, may remain undetected without additional technical diagnostic procedures such as videoproctoscopy, cinedefecography, or colpocystodefecography. The aim of the study was to review the potentials of dynamic magnetic resonance imaging defecography to elucidate the underlying anatomic and pathophysiologic background of pelvic floor disorders in proctologic patients. PATIENTS AND METHODS: Dynamic magnetic resonance imaging defecography was performed in 20 Patients (13 females) with main diagnoses such as rectal prolapse or intussusception, rectocele, descending perineum, fecal incontinence, outlet obstruction, and dyskinetic puborectalis muscle after clinical evaluation. The investigation was performed on a 1.5 T-magnetic resonance imaging machine in supine position. The rectum was filled with Gd-DTPA enriched ultrasound gel. First a T1/T2 weighted investigation of the pelvis was performed, followed by defecography with evacuation of the rectum. Images were obtained in a sagittal plane in a frequency of 1 image/second (true FISP) at rest and during straining. The obtained magnetic resonance imaging video tapes were analyzed off-line with cinematographic evaluation of bladder base, uterus, and anal canal position in relation to the pubococcygeal line by a blinded radiologist. Investigation time was 20 minutes. RESULTS: In dynamic magnetic resonance imaging defecography of the pelvic floor, 12 patients with descending perineum, 10 rectoceles (10 females), 6 cystoceles (6 females), 4 enteroceles (4 females), 8 intussusceptions (5 females), and a dyskinetic puborectalis muscle in 3 males were detected. In 11 females and 3 males multifocal disorders were found, involving more than one compartment in females, whereas in males complex defects were restricted to the posterior compartment. Magnetic resonance imaging defecography revealed diagnoses consistent with clinical results in 77.3 percent and defects in addition to clinical diagnoses in combined pelvic floor disorders in 34 percent. CONCLUSIONS: In complex pelvic floor disorders, involving more than a single defect, dynamic magnetic resonance imaging represents a convenient diagnostic procedure in females and to a lesser extent in males, in particular in terms of dynamic imaging of pelvic floor organs during defecation. In addition to the clinical assessment, dynamic magnetic resonance imaging had clinical impact in proctologic and interdisciplinary treatment.