Prediction Model for Irreversible Intestinal Ischemia in Strangulated Bowel Obstruction

Prediction Model for Irreversible Intestinal Ischemia in Strangulated Bowel Obstruction | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Prediction Model for Irreversible Intestinal Ischemia in Strangulated Bowel Obstruction Toshimichi Kobayashi, Naokazu Chiba, Itsuki Koganezawa, Masashi Nakagawa, and 8 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-1626055/v1 This work is licensed under a CC BY 4.0 License Status: Under Review Version 1 posted 8 You are reading this latest preprint version Abstract Background: Preoperatively diagnosing irreversible intestinal ischemia in patients with strangulated bowel obstruction is difficult. Therefore, this study aimed to establish a prediction model for irreversible intestinal ischemia in strangulated bowel obstruction. Methods: We included 83 patients who underwent emergency surgery for strangulated bowel obstruction between January 2014 and March 2022. The predictors of irreversible intestinal ischemia in strangulated bowel obstruction were identified using logistic regression analysis, and a prediction model for irreversible intestinal ischemia in strangulated bowel obstruction was established using the regression coefficients. Receiver operating characteristic analysis and 5-fold cross-validation was used to assess the model. Results: The prediction model (range, 0−4) was established using a white blood cell count of ≥ 12000/µL and the computed tomography value of peritoneal fluid that was ≥ 20 Hounsfield units. The areas of the receiver operating characteristic curve of the new prediction model were 0.814 and 0.807 after 5-fold cross-validation. A score of ≥ 2 was strongly suggestive of irreversible intestinal ischemia in strangulated bowel obstruction and necessitated bowel resection (odds ratio = 15.938). The bowel resection rates for the prediction scores of 0, 2, and 4 were 15.2%, 66.7%, and 85.0%, respectively. Conclusions: Our model may help predict irreversible intestinal ischemia that necessitates bowel resection for strangulated bowel obstruction cases and thus enable surgeons to recognize the severity of the situation and prepare for deterioration of patients with progression of intestinal ischemia. bowel strangulation intestinal ischemia prediction computed tomography surgical emergency preoperative diagnosis Figures Figure 1 Background Strangulated bowel obstruction (SBO) is defined as bowel obstruction with compromised intestinal blood flow and can be caused by a fibrous cord, torsion, internal hernia, or adhesions due to previous abdominal surgery [ 1 ]. SBO is a serious condition requiring early diagnosis and immediate surgery because intestinal ischemia (II) due to bowel strangulation can lead to bowel necrosis and even perforation, eventually causing septic shock. Particularly, as for SBO with irreversible II, a delayed intervention has a high risk of mortality, and the mortality rate for SBO is reportedly 16% in patients with irreversible II, compared to 3% in patients with reversible II [ 2 ]. Identifying patients with irreversible II is vital to understand the severity and manage the deteriorating condition, including perioperative intensive care. Computed tomography (CT) can detect SBO with a sensitivity ranging from 73–100% and a specificity ranging from 61–100% [ 3 ]. However, to distinguish between irreversible and reversible II in SBO preoperatively remains challenging. Regardless of experience or seniority of the surgeon, physical examination for the detection of strangulation has a success rate of only 48% [ 4 ]. Moreover, despite advances in imaging, patients requiring emergency surgery are usually poor candidates for such examinations. Particularly, reduced bowel wall enhancement on contrast-enhanced CT is reportedly a significant predictive factor [ 5 – 7 ]. However, contrast agents are contraindicated in some patients due to severe renal dysfunction or iodine allergy. Additionally, assessing the presence or absence of bowel wall enhancement highly depends on clinicians and has a poor objective value. Therefore, this study aimed to establish a prediction model for irreversible II in SBO using objective factors (other than contrast-enhanced CT findings). Methods Patients This retrospective study was approved by the Tokyo Medical University Hachioji Medical Center Ethics Committee (approval number TS2020-0358) and was conducted in accordance with the principles outlined in the 1964 Declaration of Helsinki and its later amendments. The need for informed consent was waived in view of the retrospective study design. We examined the data of 89 patients diagnosed with SBO by clinical symptoms and CT findings of closed-loop obstruction who underwent emergency operation between January 2014 and March 2021 at our department. Patients with large bowel obstruction, intraperitoneal malignancy, and a history of ascites were excluded. Finally, 83 patients were included, and all of these were confirmed for closed-loop obstruction due to mesenteric torsion or internal herniation at operation. Of these, 42 had irreversible II at laparotomy and required bowel resection (resection group; n = 42), whereas 41 had reversible II and required lysis of adhesions but not bowel resection (non-resection group; n = 41). We compared the clinical outcomes between the resection and non-resection groups. Perioperative clinical variables Preoperative clinical variables included gender, age, body mass index, previous history of laparotomy, vital signs (systolic blood pressure < 100 mmHg, body temperature ≥ 38℃), blood gas analysis (pH, base excess), and laboratory data, including white blood cell (WBC) count and C-reactive protein, hemoglobin, platelet, albumin, bilirubin, creatinine, and creatine kinase levels. Operative clinical variables included laparoscopic surgery, intraoperative presence of hemorrhagic peritoneal fluid, operation time, and blood loss. In addition, pathological findings of resection specimens included ischemia, mucosal hemorrhagic necrosis, and transluminal hemorrhagic necrosis. Radiographic variables Radiographic variables included presence of free peritoneal fluid around the strangulated intestine, emphysema, the mean CT value of the free peritoneal fluid on unenhanced CT, and reduced bowel wall enhancement on contrast-enhanced CT. The mean CT value of the free peritoneal fluid was expressed in Hounsfield units (HU) and calculated as the mean of the region-of-interest by outlining the free peritoneal fluid without adjacent structures and gases at the maximum area of free peritoneal fluid on the axial section of the CT image (shown in Fig. 1 a-b). Statistical analysis Statistical analyses were performed using the IBM SPSS Statistics, version 27.00 (IBM Corp., Armonk, NY, USA). In univariate analysis, the clinical and radiographic variables were compared between the resection and non-resection groups. The Mann–Whitney U test was used to examine the differences in continuous data. Fisher’s exact test or the χ 2 test was used to compare categorical data between groups. P < 0.05 was considered statistically significant. According to univariate analysis, preoperative clinical and radiographic variables (except for contrast-enhanced CT findings) with P < 0.05 were included in the multivariate analysis. Forward stepwise logistic regression analysis identified independent predictors of irreversible II necessitating bowel resection, and a final logistic regression model was obtained. Continuous variables were converted to binary variables at a cutoff value with the maximum Youden index, and a new prediction model was established. This model calculated the prediction score as the sum of the scores assigned to the binary variables from the independent predictors corresponding to the regression coefficient. To assess the discrimination and calibration of the prediction model, receiver operating characteristic (ROC) analysis and the Hosmer–Lemeshow test were used. To avoid overfitting, this model was evaluated using 5-fold cross-validation. The rate of bowel resection, sensitivity, specificity, and positive and negative likelihood ratios were estimated for each score. Finally, using logistic regression analysis, odds ratios (ORs) and 95% confidence intervals (CIs) were evaluated between groups categorized by the best cutoff score from the ROC analysis. The power of the two-tailed independent t-test at 5% alpha was estimated to compare the model score for the groups by using a post hoc power analysis. Results Univariate and multivariate analyses of the resection and non-resection groups The clinical and radiographic characteristics of the resection and non-resection groups are summarized in Table 1 . There were no significant differences in patient characteristics or vital signs between groups. In blood gas analysis, base excess was lower in the resection group than in the non-resection group (− 1.7 mEq/L vs. 0.35mEq/L; P = 0.006). Regarding laboratory data, only WBC counts were significantly higher in the resection group than in the non-resection group (12,550/µL vs. 9,100/µL; P < 0.001). Table 1 Comparison Between the Resection and Non-resection Groups Resection group Non-resection group P -value (n = 42) (n = 41) Patient characteristics Age 75.5 (21—94) 72 (26—96) 0.433 Male sex 15 (35.7%) 22 (53.7%) 0.1 Body mass index (kg/m 2 ) 19.9 (15.0—27.1) 20.4 (13.5—27.5) 0.909 Previous history of laparotomy 32 (76.2%) 31 (75.6%) 0.951 Vital signs Systolic blood pressure 38℃ 3 (7.1%) 3 (7.3%) 0.651 Blood gas analysis pH 7.429 (7.219—7.575) 7.438 (7.23—7.542) 0.31 Base excess (mEq/L) −1.7 (− 14.7 to 6.3) 0.35 (− 17.8 to 8.5) 0.006 Laboratory data WBC (/µL) 12,550 (4,850—34,000) 9,100 (3,060—20,600) < 0.001 CRP (mg/dL) 0.73 (0.02—28.84) 0.27 (0.02—33.16) 0.36 Hb (g/dL) 13.2 (7.4—20.6) 13.8 (8.3—22.1) 0.689 Plt (×10 4 /µL) 25.7 (8.2—74.5) 22.6 (7.6—48.2) 0.515 Alb (g/dL) 3.5 (2.1—5.0) 3.7 (1.7—4.5) 0.45 Bil (mg/dL) 0.85 (0.2—1.7) 0.8 (0.3—7.0) 0.416 Cre (mg/dL) 0.735 (0.30—5.31) 0.75 (0.31—2.84) 0.743 CK (IU/L) 75 (20—1048) 81 (10—1156) 0.996 CT findings Presence of peritoneal fluid 42 (100%) 30 (73.2%) < 0.001 Presence of emphysema 1 (2.4%) 0 (0%) 0.506 Poor or no contrast bowel wall enhancement ★ 22 (56.4%) 6 (17.1%) < 0.001 CT value of peritoneal fluid (HU) 21.4 (10.2—77.0) 15.1 (6.7—32.5) < 0.001 Operative factors Laparoscopic surgery 7 (16.7%) 15 (36.6%) 0.04 Presence of hemorrhagic peritoneal fluid 37 (88.1%) 14 (34.1%) < 0.001 Operation time (min) 104 (53–291) 74 (36–143) 0.002 Blood loss (ml) 100 (10–2425) 10 (10–1570) < 0.001 Pathological findings Ischemia 3 (7.1%) - Mucosal hemorrhagic necrosis 9 (21.4%) - Transluminal hemorrhagic necrosis 30 (71.4%) - Categorical data are expressed as percentages, and continuous data are expressed as median (min-max). ★ Contrast-enhanced CT scan was not performed in three patients in the resection group and six patients in the non-resection group. WBC, white blood cell; CRP, C-reactive protein; Hb, hemoglobin; Plt, platelet; Alb, albumin; Bil, bilirubin; Cre, creatinine; CK, creatine kinase; CT, computed tomography; HU, Hounsfield unit Unenhanced CT scans were obtained in all 83 patients, while contrast-enhanced CT scans were obtained in 74 patients, as 6 patients with severe renal function impairment and 3 with a history of allergy to iodinated contrast agents were excluded. The presence of free peritoneal fluid was the most common CT finding, present in 100% of the resection group and 73.2% of the non-resection group ( P < 0.001). Reduced bowel wall enhancement was found in 56.4% of the resection group and 17.1% of the non-resection group ( P < 0.001). The free peritoneal fluid CT value on unenhanced CT scans was significantly higher in the resection group than in the non-resection group (21.4 vs. 15.1 HU; P < 0.001). Regarding operative variables, laparoscopic surgery was performed in 16.7% and 36.6% in the resection and non-resection groups, respectively, ( P = 0.04), and hemorrhagic peritoneal fluid at operation was found in 88.l% and 34.1% of patients in the resection and non-resection groups, respectively ( P < 0.001). Operation time was significantly longer in the resection group than in the non-resection group (104 vs. 74 min; P = 0.002), and blood loss was significantly higher in the resection group than in the non-resection group (100 vs. 10 ml; P < 0.001) In addition, pathological analysis revealed findings of hemorrhagic necrosis in 92.8% of the resection specimens (transluminal hemorrhagic necrosis in 71.4% and mucosal hemorrhagic necrosis in 21.4%). Base excess, WBC count, presence of free peritoneal fluid, and peritoneal fluid CT value on unenhanced CT scans, which are significant preoperative variables on univariate analysis, were included in multivariate analysis. The forward stepwise logistic regression analysis results showed that WBC count and the peritoneal fluid CT value on unenhanced CT were significant predictors of irreversible II, necessitating bowel resection. The areas under the ROC curve (AUC) were 0.741 (95% CI: 0.633–0.849) for WBC count and 0.750 (95% CI: 0.639–0.862) for free peritoneal fluid CT value. Prediction model The prediction model was based on the final logistic regression model. WBC count and free peritoneal fluid CT value were identified as independent predictors and were converted into binary variables at the cutoff values of 12000/µL and 20 HU based on the maximum Youden’s index from the ROC curve, respectively. Patients without free peritoneal fluid were considered as having a free peritoneal fluid CT value of < 20 HU. The regression coefficients for the two binary variables in logistic regression analyses were 1.658 and 2.104, respectively. For convenience, the regression coefficient was rounded off to the nearest integer to generate scores for the two independent predictors; thus, 2 points were assigned to each variable (Table 2 ). The prediction score was calculated as the sum of the points for each of the two independent predictors and ranged from 0–4 (Table 3 ). Table 2 Predictors of Irreversible Intestinal Ischemia Necessitating Bowel Resection Variables Regression coefficient OR (95% CI) P -value Score WBC (/µl) ≥ 12000 (/µL) 1.658 5.249 (1.812—15.209) 0.002 2 CT value of free peritoneal fluid (HU) ≥ 20 (HU) 2.104 8.201 (2.633—25.537) < 0.001 2 WBC, white blood cell; CT, computed tomography; HU, Hounsfield unit; OR, odds ratio; CI, confidence interval Table 3 Prediction Model for Irreversible Intestinal Ischemia Necessitating Bowel Resection Variables Score 0 2 WBC (/µl) < 12000 ≥ 12000 CT value of free peritoneal fluid (HU) < 20 ≥ 20 The prediction score 0–4 WBC, white blood cell; CT, computed tomography; HU, Hounsfield unit The AUC for the new prediction model was 0.814 (95% CI: 0.720–0.908) and 0.807 (95% CI: 0.622–0.993) after 5-fold cross-validation, which indicated good discrimination. The Hosmer–Lemeshow test indicated adequate goodness of fit ( P = 0.391). The post hoc power analysis showed a power of 100% based on 83 patients at a 5% alpha level. The bowel resection rate and the model’s diagnostic performance are shown in Table 4 . A score of 1 was set as the optimal cutoff score based on the ROC curve, and logistic regression analysis showed that a score of 2 or higher was strongly associated with irreversible II, necessitating bowel resection (OR = 15.938, 95% CI: 5.086–49.95, P < 0.001). Table 4 The Rate of Bowel Resection and Diagnostic Performance of Each Score in Scoring Model Score Number of patients The rate of bowel resection (%) Sensitivity (%) Specificity (%) LR+ LR− 0 33 15.2 100 0 1 - 2 30 66.7 88.1 68.3 2.78 0.17 4 20 85 40.5 92.7 5.53 0.64 LR+, positive likelihood ratio; LR−, negative likelihood Discussion In this study, we established a prediction model for irreversible II necessitating bowel resection in cases of SBO. Our model is based on two independent objective predictors: the WBC count and the value of free peritoneal fluid on unenhanced CT. Systemic inflammatory response syndrome is reportedly associated with SBO [ 6 , 8 – 12 ]. Particularly, only high WBC counts have been associated with irreversible II, reflecting the severity of inflammation due to the irreversible ischemic changes found in SBO [ 10 ]. Consistent with previous studies, the WBC count was significantly higher in the resection than in the non-resection group in the present study, and the AUC was 0.741, indicating a relatively accurate prediction of irreversible II. Various CT findings, such as reduced bowel wall enhancement, increased unenhanced bowel wall attenuation, and the presence of mesenteric fluid, have been associated with irreversible II in cases of SBO [ 5 – 7 , 13 – 15 ]. In our study, the value of the free peritoneal fluid on unenhanced CT was a significant predictor of irreversible II. SBO is caused by venous occlusion due to compression of the mesentery, causing transmural hemorrhage following congestion, edema, and mucosal hemorrhage. Thus, hemorrhagic peritoneal fluid is often observed in SBO. Kobayashi et al. reported that the presence of red blood cells in the free peritoneal fluid in SBO increases according to the degree of strangulation, and the count was higher in patients with bowel resection than in those without [ 16 ]. In our study, hemorrhagic peritoneal fluid during surgery was observed more frequently in the resection than in the non-resection group, which may reflect the transmural hemorrhage due to strangulation. Previous studies have reported CT values ​​of the exudative body fluids 10 HU in cases of SBO indicate the need for bowel resection [ 19 ]. It has been suggested that the greater the hemorrhage associated with the progression of II due to strangulation, the higher the CT values of free peritoneal fluid. In our study, the AUC was 0.750, indicating a relatively accurate prediction of irreversible II. The two indicators in our prediction model are objective indicators, allowing for objective and reproducible prediction of irreversible II in SBO. Additionally, these indicators are readily available at most hospitals. Furthermore, the CT value of free peritoneal fluid can be quickly evaluated using only unenhanced CT scans. Reduced bowel wall enhancement on contrast-enhanced CT has been reported as being helpful in predicting irreversible II in SBO, with a sensitivity of 75–81% and specificity of 19–74% [ 5 , 7 , 14 ]. However, contrast-enhanced CT may be contraindicated in patients with severe renal dysfunction or iodine allergy. In contrast, our model is useful even when contrast agents are contraindicated. In our model, higher scores were associated with a higher probability of bowel resection. At a score of 0 (with a probability of 15.2%), immediate surgery may avoid a bowel resection for many patients with SBO. Moreover, it may be sufficient to release the strangulation, allowing to choose laparoscopic surgery. In this study, laparoscopic surgery was performed significantly more often in the non-resection group than in the resection group. Conversely, at a score of 4 (with a probability of 85%), open surgery may be preferable considering the need for emergency resection of the ischemic bowel. In addition, respiratory and circulatory management may be considered as a precaution against further deterioration in patients with progressive intestinal ischemia. Furthermore, higher scores were also associated with higher rates of necrosis in the resection specimens. All 17 specimens at a score of 4 in the resection group showed pathological hemorrhagic necrosis, and of them, 14 (82.4%) specimens showed transluminal hemorrhagic necrosis (data not shown). Our study has several limitations. This was a single-center retrospective study with a small sample size. Multi-center prospective studies with large sample sizes are required to support the findings. To reduce overfitting, 5-fold cross-validation was used to assess the internal validation of our prediction model. However, additional external validation is necessary to verify its application. Conclusions In conclusion, we established a prediction model for irreversible II in cases of SBO based on objective variables, namely the WBC count and the CT value of free peritoneal fluid on unenhanced CT scans. Our model can be made readily available in most hospitals and may enable surgeons to recognize the severity of the situation and prepare for the deterioration of patients with progression of intestinal ischemia. Abbreviations AUC, area under the receiver operating characteristic curve CI, confidence interval CT, computed tomography HU, Hounsfield units II, intestinal ischemia OR, odds ratio ROC, receiver operating characteristic SBO, strangulated bowel obstruction WBC, white blood cell Declarations Ethics approval and consent to participate: This retrospective study was approved by the Tokyo Medical University Hachioji Medical Center Ethics Committee (approval number TS2020-0358) and was conducted in accordance with the principles outlined in the 1964 Declaration of Helsinki and its later amendments. The need for informed consent was waived in view of the retrospective study design. Consent for publication: Not applicable. Availability of data and materials All data generated or analyzed during this study are included in this article. Further inquiries can be directed to the corresponding author. Competing Interests: The authors declare that they have no competing interests. Funding The author(s) received no specific funding for this work. Author Contributions Study conception and design: TK, NC, and SK Acquisition of data: TK Operation procedures: All authors Analysis and interpretation of data: TK Drafting of manuscript: TK Critical revision of manuscript: All authors Acknowledgements Not applicable. References Hashimoto D, Hirota M, Matsukawa T, Yagi Y, Baba H. Clinical features of strangulated small bowel obstruction. Surg Today. 2012;42:1061-5. Fevang BT, Fevang J, Stangeland L, Søreide O, Svanes K, Viste A. Complications and death after surgical treatment of small bowel obstruction: a 35-year institutional experience. Ann Surg. 2000;231:529-37. Millet I, Taourel P, Ruyer A, Molinari N. Value of CT findings to predict surgical ischemia in small bowel obstruction: a systematic review and meta-analysis. Eur Radiol. 2015;25:1823-35. Ten Broek RPG, Krielen P, Di Saverio S, Coccolini F, Biffl WL, Ansaloni L, et al. 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Matsushima K, Inaba K, Dollbaum R, Cheng V, Khan M, Herr K, et al. High-density free fluid on computed tomography: a predictor of surgical intervention in patients with adhesive small bowel obstruction. J Gastrointest Surg. 2016;20:1861-6. Additional Declarations No competing interests reported. Cite Share Download PDF Status: Under Review Version 1 posted Editorial decision: Major revision 22 Jul, 2022 Reviews received at journal 20 May, 2022 Reviewers agreed at journal 11 May, 2022 Reviewers invited by journal 11 May, 2022 Editor assigned by journal 11 May, 2022 Editor invited by journal 07 May, 2022 Submission checks completed at journal 07 May, 2022 First submitted to journal 05 May, 2022 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. 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Yokozuka","email":"","orcid":"","institution":"Tokyo Medical University Hachioji Medical Center","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Kei","middleName":"","lastName":"Yokozuka","suffix":""},{"id":104269323,"identity":"7ea4d940-751e-4270-b9dd-eb3769a5eaa7","order_by":5,"name":"Shigeto Ochiai","email":"","orcid":"","institution":"Tokyo Medical University Hachioji Medical Center","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Shigeto","middleName":"","lastName":"Ochiai","suffix":""},{"id":104269324,"identity":"64e77fdf-15d1-468a-841f-b922a89ddc5c","order_by":6,"name":"Takahiro Gunji","email":"","orcid":"","institution":"Tokyo Medical University Hachioji Medical Center","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Takahiro","middleName":"","lastName":"Gunji","suffix":""},{"id":104269327,"identity":"31c75353-9149-4780-890f-a90441513022","order_by":7,"name":"Toru Sano","email":"","orcid":"","institution":"Tokyo Medical University Hachioji Medical Center","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Toru","middleName":"","lastName":"Sano","suffix":""},{"id":104269328,"identity":"194a7ff5-18b2-47a6-8a5d-7c6b132611ad","order_by":8,"name":"Koichi Tomita","email":"","orcid":"","institution":"Tokyo Medical University Hachioji Medical Center","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Koichi","middleName":"","lastName":"Tomita","suffix":""},{"id":104269331,"identity":"c8f4e6d2-3376-4fd5-b6e2-194f39ac0fb3","order_by":9,"name":"Satoshi Tabuchi","email":"","orcid":"","institution":"Tokyo Medical University Hachioji Medical Center","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Satoshi","middleName":"","lastName":"Tabuchi","suffix":""},{"id":104269332,"identity":"0e838df6-8099-4931-b3f4-5ddc0a3f81df","order_by":10,"name":"Eiji Hidaka","email":"","orcid":"","institution":"Tokyo Medical University Hachioji Medical Center","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Eiji","middleName":"","lastName":"Hidaka","suffix":""},{"id":104269333,"identity":"cec8a0ff-979e-433f-aedf-54c1852638fa","order_by":11,"name":"Shigeyuki Kawachi","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAABBUlEQVRIiWNgGAWjYDACHjB5gIefgYEZKpQAItgIa5FsI1ULg8ExVC24gXzP4WcSP2ruyBjfbz5szFPBEM3PnsD44QcDXx4uLQZn28wke4494zE7xpaczHOGIXdmzwNmyR4GtmKcWvgZzG7wNhwGauExPszb9j93w40EBmmgXxIbcDmsn/3bzb9ALcZtYC0MuftvJDD/xqeF4WyP2W2QLQZsPMbJIC0bJBLY8NpicOZM+W+ZY4d5JI6lJRvOAfplxpmHbZY9Brj9It+TvtnwTc1he/7mw4cl3lQw5Pa3Jx++8aPiGM4QQwFMkEhiBDrJ4FgCUVoYfyDYNcRpGQWjYBSMgpEAAJCcViVdxqiYAAAAAElFTkSuQmCC","orcid":"","institution":"Tokyo Medical University Hachioji Medical Center","correspondingAuthor":true,"submittingAuthor":false,"prefix":"","firstName":"Shigeyuki","middleName":"","lastName":"Kawachi","suffix":""}],"badges":[],"createdAt":"2022-05-05 12:44:17","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-1626055/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-1626055/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":21356536,"identity":"6f18f792-2251-4ce3-a209-3cbfea85007a","added_by":"auto","created_at":"2022-05-11 17:26:49","extension":"jpeg","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":61532,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eCT values of peritoneal fluid. \u003c/strong\u003eFree peritoneal fluid in the rectovesical pouch (\u003cstrong\u003ea\u003c/strong\u003e) and below the right diaphragm (\u003cstrong\u003eb\u003c/strong\u003e) on non-enhanced computed tomography (CT) with mean CT values of 9.6 Hounsfield units (HU) and 38.6 HU, respectively, using a region-of-interest analysis.\u003c/p\u003e","description":"","filename":"floatimage1.jpeg","url":"https://assets-eu.researchsquare.com/files/rs-1626055/v1/452088240950335ee5dec73e.jpeg"},{"id":21356537,"identity":"1922aa09-5308-48f2-bced-fd52645cecff","added_by":"auto","created_at":"2022-05-11 17:26:52","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":465163,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-1626055/v1/577467f8-139c-4041-aafd-bfa4a2758027.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Prediction Model for Irreversible Intestinal Ischemia in Strangulated Bowel Obstruction","fulltext":[{"header":"Background","content":"\u003cp\u003eStrangulated bowel obstruction (SBO) is defined as bowel obstruction with compromised intestinal blood flow and can be caused by a fibrous cord, torsion, internal hernia, or adhesions due to previous abdominal surgery [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e]. SBO is a serious condition requiring early diagnosis and immediate surgery because intestinal ischemia (II) due to bowel strangulation can lead to bowel necrosis and even perforation, eventually causing septic shock. Particularly, as for SBO with irreversible II, a delayed intervention has a high risk of mortality, and the mortality rate for SBO is reportedly 16% in patients with irreversible II, compared to 3% in patients with reversible II [\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e]. Identifying patients with irreversible II is vital to understand the severity and manage the deteriorating condition, including perioperative intensive care.\u003c/p\u003e \u003cp\u003eComputed tomography (CT) can detect SBO with a sensitivity ranging from 73\u0026ndash;100% and a specificity ranging from 61\u0026ndash;100% [\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e]. However, to distinguish between irreversible and reversible II in SBO preoperatively remains challenging. Regardless of experience or seniority of the surgeon, physical examination for the detection of strangulation has a success rate of only 48% [\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e]. Moreover, despite advances in imaging, patients requiring emergency surgery are usually poor candidates for such examinations. Particularly, reduced bowel wall enhancement on contrast-enhanced CT is reportedly a significant predictive factor [\u003cspan additionalcitationids=\"CR6\" citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e]. However, contrast agents are contraindicated in some patients due to severe renal dysfunction or iodine allergy. Additionally, assessing the presence or absence of bowel wall enhancement highly depends on clinicians and has a poor objective value. Therefore, this study aimed to establish a prediction model for irreversible II in SBO using objective factors (other than contrast-enhanced CT findings).\u003c/p\u003e"},{"header":"Methods","content":"\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e \u003ch2\u003ePatients\u003c/h2\u003e \u003cp\u003e This retrospective study was approved by the Tokyo Medical University Hachioji Medical Center Ethics Committee (approval number TS2020-0358) and was conducted in accordance with the principles outlined in the 1964 Declaration of Helsinki and its later amendments. The need for informed consent was waived in view of the retrospective study design. We examined the data of 89 patients diagnosed with SBO by clinical symptoms and CT findings of closed-loop obstruction who underwent emergency operation between January 2014 and March 2021 at our department. Patients with large bowel obstruction, intraperitoneal malignancy, and a history of ascites were excluded. Finally, 83 patients were included, and all of these were confirmed for closed-loop obstruction due to mesenteric torsion or internal herniation at operation. Of these, 42 had irreversible II at laparotomy and required bowel resection (resection group; n\u0026thinsp;=\u0026thinsp;42), whereas 41 had reversible II and required lysis of adhesions but not bowel resection (non-resection group; n\u0026thinsp;=\u0026thinsp;41). We compared the clinical outcomes between the resection and non-resection groups.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec4\" class=\"Section2\"\u003e \u003ch2\u003ePerioperative clinical variables\u003c/h2\u003e \u003cp\u003ePreoperative clinical variables included gender, age, body mass index, previous history of laparotomy, vital signs (systolic blood pressure\u0026thinsp;\u0026lt;\u0026thinsp;100 mmHg, body temperature\u0026thinsp;\u0026ge;\u0026thinsp;38℃), blood gas analysis (pH, base excess), and laboratory data, including white blood cell (WBC) count and C-reactive protein, hemoglobin, platelet, albumin, bilirubin, creatinine, and creatine kinase levels. Operative clinical variables included laparoscopic surgery, intraoperative presence of hemorrhagic peritoneal fluid, operation time, and blood loss. In addition, pathological findings of resection specimens included ischemia, mucosal hemorrhagic necrosis, and transluminal hemorrhagic necrosis.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec5\" class=\"Section2\"\u003e \u003ch2\u003eRadiographic variables\u003c/h2\u003e \u003cp\u003eRadiographic variables included presence of free peritoneal fluid around the strangulated intestine, emphysema, the mean CT value of the free peritoneal fluid on unenhanced CT, and reduced bowel wall enhancement on contrast-enhanced CT. The mean CT value of the free peritoneal fluid was expressed in Hounsfield units (HU) and calculated as the mean of the region-of-interest by outlining the free peritoneal fluid without adjacent structures and gases at the maximum area of free peritoneal fluid on the axial section of the CT image (shown in Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003ea-b).\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec6\" class=\"Section2\"\u003e \u003ch2\u003eStatistical analysis\u003c/h2\u003e \u003cp\u003eStatistical analyses were performed using the IBM SPSS Statistics, version 27.00 (IBM Corp., Armonk, NY, USA). In univariate analysis, the clinical and radiographic variables were compared between the resection and non-resection groups. The Mann\u0026ndash;Whitney U test was used to examine the differences in continuous data. Fisher\u0026rsquo;s exact test or the χ\u003csup\u003e2\u003c/sup\u003e test was used to compare categorical data between groups. \u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.05 was considered statistically significant.\u003c/p\u003e \u003cp\u003eAccording to univariate analysis, preoperative clinical and radiographic variables (except for contrast-enhanced CT findings) with \u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.05 were included in the multivariate analysis. Forward stepwise logistic regression analysis identified independent predictors of irreversible II necessitating bowel resection, and a final logistic regression model was obtained. Continuous variables were converted to binary variables at a cutoff value with the maximum Youden index, and a new prediction model was established. This model calculated the prediction score as the sum of the scores assigned to the binary variables from the independent predictors corresponding to the regression coefficient. To assess the discrimination and calibration of the prediction model, receiver operating characteristic (ROC) analysis and the Hosmer\u0026ndash;Lemeshow test were used. To avoid overfitting, this model was evaluated using 5-fold cross-validation. The rate of bowel resection, sensitivity, specificity, and positive and negative likelihood ratios were estimated for each score. Finally, using logistic regression analysis, odds ratios (ORs) and 95% confidence intervals (CIs) were evaluated between groups categorized by the best cutoff score from the ROC analysis. The power of the two-tailed independent t-test at 5% alpha was estimated to compare the model score for the groups by using a post hoc power analysis.\u003c/p\u003e \u003c/div\u003e"},{"header":"Results","content":"\u003cdiv id=\"Sec8\" class=\"Section2\"\u003e \u003ch2\u003eUnivariate and multivariate analyses of the resection and non-resection groups\u003c/h2\u003e \u003cp\u003eThe clinical and radiographic characteristics of the resection and non-resection groups are summarized in Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e. There were no significant differences in patient characteristics or vital signs between groups. In blood gas analysis, base excess was lower in the resection group than in the non-resection group (\u0026minus;\u0026thinsp;1.7 mEq/L vs. 0.35mEq/L; \u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.006). Regarding laboratory data, only WBC counts were significantly higher in the resection group than in the non-resection group (12,550/\u0026micro;L vs. 9,100/\u0026micro;L; \u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.001).\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab1\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eComparison Between the Resection and Non-resection Groups\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"4\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eResection group\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eNon-resection group\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003e\u003cem\u003eP\u003c/em\u003e-value\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u003cb\u003e(n\u0026thinsp;=\u0026thinsp;42)\u003c/b\u003e\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u003cb\u003e(n\u0026thinsp;=\u0026thinsp;41)\u003c/b\u003e\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003ePatient characteristics\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAge\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e75.5 (21\u0026mdash;94)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e72 (26\u0026mdash;96)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.433\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMale sex\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e15 (35.7%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e22 (53.7%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.1\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eBody mass index (kg/m\u003csup\u003e2\u003c/sup\u003e)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e19.9 (15.0\u0026mdash;27.1)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e20.4 (13.5\u0026mdash;27.5)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.909\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePrevious history of laparotomy\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e32 (76.2%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e31 (75.6%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.951\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eVital signs\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSystolic blood pressure\u0026thinsp;\u0026lt;\u0026thinsp;100mmHg\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e4 (9.5%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1 (2.4%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.187\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eBody temperature\u0026thinsp;\u0026gt;\u0026thinsp;38℃\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e3 (7.1%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e3 (7.3%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.651\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eBlood gas analysis\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003epH\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e7.429 (7.219\u0026mdash;7.575)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e7.438 (7.23\u0026mdash;7.542)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.31\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eBase excess (mEq/L)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u0026minus;1.7 (\u0026minus;\u0026thinsp;14.7 to 6.3)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.35 (\u0026minus;\u0026thinsp;17.8 to 8.5)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.006\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eLaboratory data\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eWBC (/\u0026micro;L)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e12,550 (4,850\u0026mdash;34,000)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e9,100 (3,060\u0026mdash;20,600)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCRP (mg/dL)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.73 (0.02\u0026mdash;28.84)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.27 (0.02\u0026mdash;33.16)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.36\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eHb (g/dL)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e13.2 (7.4\u0026mdash;20.6)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e13.8 (8.3\u0026mdash;22.1)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.689\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePlt (\u0026times;10\u003csup\u003e4\u003c/sup\u003e/\u0026micro;L)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e25.7 (8.2\u0026mdash;74.5)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e22.6 (7.6\u0026mdash;48.2)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.515\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAlb (g/dL)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e3.5 (2.1\u0026mdash;5.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e3.7 (1.7\u0026mdash;4.5)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.45\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eBil (mg/dL)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.85 (0.2\u0026mdash;1.7)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.8 (0.3\u0026mdash;7.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.416\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCre (mg/dL)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.735 (0.30\u0026mdash;5.31)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.75 (0.31\u0026mdash;2.84)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.743\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCK (IU/L)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e75 (20\u0026mdash;1048)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e81 (10\u0026mdash;1156)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.996\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eCT findings\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePresence of peritoneal fluid\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e42 (100%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e30 (73.2%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePresence of emphysema\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1 (2.4%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0 (0%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.506\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePoor or no contrast bowel wall enhancement\u003csup\u003e★\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e22 (56.4%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e6 (17.1%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCT value of peritoneal fluid (HU)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e21.4 (10.2\u0026mdash;77.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e15.1 (6.7\u0026mdash;32.5)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eOperative factors\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eLaparoscopic surgery\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e7 (16.7%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e15 (36.6%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.04\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePresence of hemorrhagic peritoneal fluid\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e37 (88.1%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e14 (34.1%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eOperation time (min)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e104 (53\u0026ndash;291)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e74 (36\u0026ndash;143)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.002\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eBlood loss (ml)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e100 (10\u0026ndash;2425)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e10 (10\u0026ndash;1570)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003ePathological findings\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eIschemia\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e3 (7.1%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMucosal hemorrhagic necrosis\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e9 (21.4%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eTransluminal hemorrhagic necrosis\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e30 (71.4%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"4\" nameend=\"c4\" namest=\"c1\"\u003e \u003cp\u003eCategorical data are expressed as percentages, and continuous data are expressed as median (min-max).\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"4\" nameend=\"c4\" namest=\"c1\"\u003e \u003cp\u003e\u003csup\u003e★\u003c/sup\u003eContrast-enhanced CT scan was not performed in three patients in the resection group and six patients in the non-resection group.\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"4\" nameend=\"c4\" namest=\"c1\"\u003e \u003cp\u003eWBC, white blood cell; CRP, C-reactive protein; Hb, hemoglobin; Plt, platelet; Alb, albumin; Bil, bilirubin; Cre, creatinine; CK, creatine kinase; CT, computed tomography; HU, Hounsfield unit\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003eUnenhanced CT scans were obtained in all 83 patients, while contrast-enhanced CT scans were obtained in 74 patients, as 6 patients with severe renal function impairment and 3 with a history of allergy to iodinated contrast agents were excluded. The presence of free peritoneal fluid was the most common CT finding, present in 100% of the resection group and 73.2% of the non-resection group (\u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.001). Reduced bowel wall enhancement was found in 56.4% of the resection group and 17.1% of the non-resection group (\u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.001). The free peritoneal fluid CT value on unenhanced CT scans was significantly higher in the resection group than in the non-resection group (21.4 vs. 15.1 HU; \u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.001).\u003c/p\u003e \u003cp\u003eRegarding operative variables, laparoscopic surgery was performed in 16.7% and 36.6% in the resection and non-resection groups, respectively, (\u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.04), and hemorrhagic peritoneal fluid at operation was found in 88.l% and 34.1% of patients in the resection and non-resection groups, respectively (\u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.001). Operation time was significantly longer in the resection group than in the non-resection group (104 vs. 74 min; \u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.002), and blood loss was significantly higher in the resection group than in the non-resection group (100 vs. 10 ml; \u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.001)\u003c/p\u003e \u003cp\u003eIn addition, pathological analysis revealed findings of hemorrhagic necrosis in 92.8% of the resection specimens (transluminal hemorrhagic necrosis in 71.4% and mucosal hemorrhagic necrosis in 21.4%).\u003c/p\u003e \u003cp\u003eBase excess, WBC count, presence of free peritoneal fluid, and peritoneal fluid CT value on unenhanced CT scans, which are significant preoperative variables on univariate analysis, were included in multivariate analysis. The forward stepwise logistic regression analysis results showed that WBC count and the peritoneal fluid CT value on unenhanced CT were significant predictors of irreversible II, necessitating bowel resection. The areas under the ROC curve (AUC) were 0.741 (95% CI: 0.633\u0026ndash;0.849) for WBC count and 0.750 (95% CI: 0.639\u0026ndash;0.862) for free peritoneal fluid CT value.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec9\" class=\"Section2\"\u003e \u003ch2\u003ePrediction model\u003c/h2\u003e \u003cp\u003eThe prediction model was based on the final logistic regression model. WBC count and free peritoneal fluid CT value were identified as independent predictors and were converted into binary variables at the cutoff values of 12000/\u0026micro;L and 20 HU based on the maximum Youden\u0026rsquo;s index from the ROC curve, respectively. Patients without free peritoneal fluid were considered as having a free peritoneal fluid CT value of \u0026lt;\u0026thinsp;20 HU. The regression coefficients for the two binary variables in logistic regression analyses were 1.658 and 2.104, respectively. For convenience, the regression coefficient was rounded off to the nearest integer to generate scores for the two independent predictors; thus, 2 points were assigned to each variable (Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e). The prediction score was calculated as the sum of the points for each of the two independent predictors and ranged from 0\u0026ndash;4 (Table\u0026nbsp;\u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e).\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab2\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 2\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003ePredictors of Irreversible Intestinal Ischemia Necessitating Bowel Resection\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"5\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eVariables\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eRegression coefficient\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eOR (95% CI)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u003cem\u003eP\u003c/em\u003e-value\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003eScore\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eWBC (/\u0026micro;l)\u0026thinsp;\u0026ge;\u0026thinsp;12000 (/\u0026micro;L)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1.658\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e5.249 (1.812\u0026mdash;15.209)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.002\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e2\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCT value of free peritoneal fluid (HU)\u0026thinsp;\u0026ge;\u0026thinsp;20 (HU)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e2.104\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e8.201 (2.633\u0026mdash;25.537)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.001\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e2\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"5\" nameend=\"c5\" namest=\"c1\"\u003e \u003cp\u003eWBC, white blood cell; CT, computed tomography; HU, Hounsfield unit; OR, odds ratio; CI, confidence interval\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab3\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 3\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003ePrediction Model for Irreversible Intestinal Ischemia Necessitating Bowel Resection\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"3\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eVariables\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"2\" nameend=\"c3\" namest=\"c2\"\u003e \u003cp\u003eScore\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003e2\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eWBC (/\u0026micro;l)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;12000\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u0026ge;\u0026thinsp;12000\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCT value of free peritoneal fluid (HU)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;20\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u0026ge;\u0026thinsp;20\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eThe prediction score\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c3\" namest=\"c2\"\u003e \u003cp\u003e0\u0026ndash;4\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"3\" nameend=\"c3\" namest=\"c1\"\u003e \u003cp\u003eWBC, white blood cell; CT, computed tomography; HU, Hounsfield unit\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003eThe AUC for the new prediction model was 0.814 (95% CI: 0.720\u0026ndash;0.908) and 0.807 (95% CI: 0.622\u0026ndash;0.993) after 5-fold cross-validation, which indicated good discrimination. The Hosmer\u0026ndash;Lemeshow test indicated adequate goodness of fit (\u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.391). The post hoc power analysis showed a power of 100% based on 83 patients at a 5% alpha level.\u003c/p\u003e \u003cp\u003eThe bowel resection rate and the model\u0026rsquo;s diagnostic performance are shown in Table\u0026nbsp;\u003cspan refid=\"Tab4\" class=\"InternalRef\"\u003e4\u003c/span\u003e. A score of 1 was set as the optimal cutoff score based on the ROC curve, and logistic regression analysis showed that a score of 2 or higher was strongly associated with irreversible II, necessitating bowel resection (OR\u0026thinsp;=\u0026thinsp;15.938, 95% CI: 5.086\u0026ndash;49.95, \u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.001).\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab4\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 4\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eThe Rate of Bowel Resection and Diagnostic Performance of Each Score in Scoring Model\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"7\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c7\" colnum=\"7\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eScore\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eNumber of patients\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eThe rate of bowel resection (%)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eSensitivity (%)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003eSpecificity (%)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c6\"\u003e \u003cp\u003eLR+\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c7\"\u003e \u003cp\u003eLR\u0026minus;\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e33\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e15.2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e100\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e30\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e66.7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e88.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e68.3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e2.78\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.17\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e20\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e85\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e40.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e92.7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e5.53\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.64\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"7\" nameend=\"c7\" namest=\"c1\"\u003e \u003cp\u003eLR+, positive likelihood ratio; LR\u0026minus;, negative likelihood\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003c/div\u003e"},{"header":"Discussion","content":"\u003cp\u003eIn this study, we established a prediction model for irreversible II necessitating bowel resection in cases of SBO. Our model is based on two independent objective predictors: the WBC count and the value of free peritoneal fluid on unenhanced CT.\u003c/p\u003e \u003cp\u003eSystemic inflammatory response syndrome is reportedly associated with SBO [\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e, \u003cspan additionalcitationids=\"CR9 CR10 CR11\" citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e]. Particularly, only high WBC counts have been associated with irreversible II, reflecting the severity of inflammation due to the irreversible ischemic changes found in SBO [\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e]. Consistent with previous studies, the WBC count was significantly higher in the resection than in the non-resection group in the present study, and the AUC was 0.741, indicating a relatively accurate prediction of irreversible II.\u003c/p\u003e \u003cp\u003eVarious CT findings, such as reduced bowel wall enhancement, increased unenhanced bowel wall attenuation, and the presence of mesenteric fluid, have been associated with irreversible II in cases of SBO [\u003cspan additionalcitationids=\"CR6\" citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e, \u003cspan additionalcitationids=\"CR14\" citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e]. In our study, the value of the free peritoneal fluid on unenhanced CT was a significant predictor of irreversible II. SBO is caused by venous occlusion due to compression of the mesentery, causing transmural hemorrhage following congestion, edema, and mucosal hemorrhage. Thus, hemorrhagic peritoneal fluid is often observed in SBO. Kobayashi et al. reported that the presence of red blood cells in the free peritoneal fluid in SBO increases according to the degree of strangulation, and the count was higher in patients with bowel resection than in those without [\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e]. In our study, hemorrhagic peritoneal fluid during surgery was observed more frequently in the resection than in the non-resection group, which may reflect the transmural hemorrhage due to strangulation. Previous studies have reported CT values ​​of the exudative body fluids\u0026thinsp;\u0026lt;\u0026thinsp;10 HU [\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e], while those of hemorrhagic peritoneal fluid range from 15\u0026ndash;75 HU [\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e]. A recent study reported that CT values of peritoneal fluid\u0026thinsp;\u0026gt;\u0026thinsp;10 HU in cases of SBO indicate the need for bowel resection [\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e]. It has been suggested that the greater the hemorrhage associated with the progression of II due to strangulation, the higher the CT values of free peritoneal fluid. In our study, the AUC was 0.750, indicating a relatively accurate prediction of irreversible II.\u003c/p\u003e \u003cp\u003eThe two indicators in our prediction model are objective indicators, allowing for objective and reproducible prediction of irreversible II in SBO. Additionally, these indicators are readily available at most hospitals. Furthermore, the CT value of free peritoneal fluid can be quickly evaluated using only unenhanced CT scans. Reduced bowel wall enhancement on contrast-enhanced CT has been reported as being helpful in predicting irreversible II in SBO, with a sensitivity of 75\u0026ndash;81% and specificity of 19\u0026ndash;74% [\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e, \u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e, \u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e]. However, contrast-enhanced CT may be contraindicated in patients with severe renal dysfunction or iodine allergy. In contrast, our model is useful even when contrast agents are contraindicated.\u003c/p\u003e \u003cp\u003eIn our model, higher scores were associated with a higher probability of bowel resection. At a score of 0 (with a probability of 15.2%), immediate surgery may avoid a bowel resection for many patients with SBO. Moreover, it may be sufficient to release the strangulation, allowing to choose laparoscopic surgery. In this study, laparoscopic surgery was performed significantly more often in the non-resection group than in the resection group. Conversely, at a score of 4 (with a probability of 85%), open surgery may be preferable considering the need for emergency resection of the ischemic bowel. In addition, respiratory and circulatory management may be considered as a precaution against further deterioration in patients with progressive intestinal ischemia. Furthermore, higher scores were also associated with higher rates of necrosis in the resection specimens. All 17 specimens at a score of 4 in the resection group showed pathological hemorrhagic necrosis, and of them, 14 (82.4%) specimens showed transluminal hemorrhagic necrosis (data not shown).\u003c/p\u003e \u003cp\u003eOur study has several limitations. This was a single-center retrospective study with a small sample size. Multi-center prospective studies with large sample sizes are required to support the findings. To reduce overfitting, 5-fold cross-validation was used to assess the internal validation of our prediction model. However, additional external validation is necessary to verify its application.\u003c/p\u003e"},{"header":"Conclusions","content":"\u003cp\u003eIn conclusion, we established a prediction model for irreversible II in cases of SBO based on objective variables, namely the WBC count and the CT value of free peritoneal fluid on unenhanced CT scans. Our model can be made readily available in most hospitals and may enable surgeons to recognize the severity of the situation and prepare for the deterioration of patients with progression of intestinal ischemia.\u003c/p\u003e"},{"header":"Abbreviations","content":"\u003cp\u003eAUC, area under the receiver operating characteristic curve\u003c/p\u003e\n\u003cp\u003e\u003cspan lang=\"\"\u003eCI, confidence interval\u003c/span\u003e\u003c/p\u003e\n\u003cp\u003e\u003cspan lang=\"\"\u003eCT, computed tomography\u0026nbsp;\u003c/span\u003e\u003c/p\u003e\n\u003cp\u003e\u003cspan lang=\"\"\u003eHU, Hounsfield units\u0026nbsp;\u003c/span\u003e\u003c/p\u003e\n\u003cp\u003e\u003cspan lang=\"\"\u003eII, intestinal ischemia\u003c/span\u003e\u003c/p\u003e\n\u003cp\u003e\u003cspan lang=\"\"\u003eOR, odds ratio\u0026nbsp;\u003c/span\u003e\u003c/p\u003e\n\u003cp\u003e\u003cspan lang=\"\"\u003eROC, receiver operating characteristic\u0026nbsp;\u003c/span\u003e\u003c/p\u003e\n\u003cp\u003e\u003cspan lang=\"\"\u003eSBO, strangulated bowel obstruction\u003c/span\u003e\u003c/p\u003e\n\u003cp\u003e\u003cspan lang=\"\"\u003eWBC, white blood cell\u003c/span\u003e\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003e\u003cspan lang=\"\"\u003eEthics approval and consent to participate:\u003c/span\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cspan lang=\"\"\u003eThis retrospective study was approved by the Tokyo Medical University Hachioji Medical Center Ethics Committee (approval number TS2020-0358) and was conducted in accordance with the principles outlined in the 1964 Declaration of Helsinki and its later amendments.\u003c/span\u003e\u003cspan lang=\"\"\u003e\u0026nbsp;\u003c/span\u003e\u003cspan lang=\"\"\u003eThe need for informed consent was waived in view of the retrospective study design.\u003c/span\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cspan lang=\"\"\u003eConsent for publication:\u003c/span\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cspan lang=\"\"\u003eNot applicable.\u003c/span\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cspan lang=\"\"\u003eAvailability of data and materials\u003c/span\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cspan lang=\"\"\u003eAll data generated or analyzed during this study are included in this article. Further inquiries can be directed to the corresponding author.\u003c/span\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cspan lang=\"\"\u003eCompeting Interests:\u003c/span\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cspan lang=\"\"\u003eThe authors declare that they have no competing interests.\u003c/span\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cspan lang=\"\"\u003eFunding\u0026nbsp;\u003c/span\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cspan lang=\"\"\u003eThe author(s) received no specific funding for this work.\u003c/span\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cspan lang=\"\"\u003eAuthor Contributions\u003c/span\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cspan lang=\"\"\u003eStudy conception and design: TK, NC, and SK\u003c/span\u003e\u003c/p\u003e\n\u003cp\u003e\u003cspan lang=\"\"\u003eAcquisition of data: TK\u003c/span\u003e\u003c/p\u003e\n\u003cp\u003e\u003cspan lang=\"\"\u003eOperation procedures: All authors\u003c/span\u003e\u003c/p\u003e\n\u003cp\u003e\u003cspan lang=\"\"\u003eAnalysis and interpretation of data: TK\u003c/span\u003e\u003c/p\u003e\n\u003cp\u003e\u003cspan lang=\"\"\u003eDrafting of manuscript: TK\u003c/span\u003e\u003c/p\u003e\n\u003cp\u003e\u003cspan lang=\"\"\u003eCritical revision of manuscript: All authors\u003c/span\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cspan lang=\"\"\u003eAcknowledgements\u003c/span\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cspan lang=\"\"\u003eNot applicable.\u003c/span\u003e\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n \u003cli\u003eHashimoto D, Hirota M, Matsukawa T, Yagi Y, Baba H. Clinical features of strangulated small bowel obstruction. Surg Today. 2012;42:1061-5.\u0026nbsp;\u003c/li\u003e\n \u003cli\u003eFevang BT, Fevang J, Stangeland L, S\u0026oslash;reide O, Svanes K, Viste A. Complications and death after surgical treatment of small bowel obstruction: a 35-year institutional experience. Ann Surg. 2000;231:529-37.\u003c/li\u003e\n \u003cli\u003eMillet I, Taourel P, Ruyer A, Molinari N. Value of CT findings to predict surgical ischemia in small bowel obstruction: a systematic review and meta-analysis. Eur Radiol. 2015;25:1823-35.\u0026nbsp;\u003c/li\u003e\n \u003cli\u003eTen Broek RPG, Krielen P, Di Saverio S, Coccolini F, Biffl WL, Ansaloni L, et al. Bologna guidelines for diagnosis and management of adhesive small bowel obstruction (ASBO): 2017 update of the evidence-based guidelines from the world society of emergency surgery ASBO working group. World J Emerg Surg. 2018;13:24.\u0026nbsp;\u003c/li\u003e\n \u003cli\u003eMillet I, Boutot D, Faget C, Pages-Bouic E, Molinari N, Zins M, et al. Assessment of strangulation in adhesive small bowel obstruction on the basis of combined CT findings: implications for clinical care. Radiology. 2017;285:798-808.\u0026nbsp;\u003c/li\u003e\n \u003cli\u003eSchwenter F, Poletti PA, Platon A, Perneger T, Morel P, Gervaz P. Clinicoradiological score for predicting the risk of strangulated small bowel obstruction. Br J Surg. 2010;97:1119-25.\u0026nbsp;\u003c/li\u003e\n \u003cli\u003eNakashima K, Ishimaru H, Fujimoto T, Mizowaki T, Mitarai K, Nakashima K, et al. Diagnostic performance of CT findings for bowel ischemia and necrosis in closed-loop small-bowel obstruction. Abdom Imaging. 2015;40:1097-103.\u0026nbsp;\u003c/li\u003e\n \u003cli\u003eHuang X, Fang G, Lin J, Xu K, Shi H, Zhuang L. A prediction model for recognizing strangulated small bowel obstruction. Gastroenterol Res Pract. 2018;2018:7164648.\u0026nbsp;\u003c/li\u003e\n \u003cli\u003eMu JF, Wang Q, Wang SD, Wang C, Song JX, Jiang J, et al. Clinical factors associated with intestinal strangulating obstruction and recurrence in adhesive small bowel obstruction: a retrospective study of 288 cases. Medicine. 2018;97:e12011.\u0026nbsp;\u003c/li\u003e\n \u003cli\u003e Miyauchi T, Kuroda T, Nisioka M, Hashimoto T, Kasamatu T, Kuratate S, et al. Clinical study of strangulation obstruction of the small bowel. J Med Invest. 2001;48:66-72.\u003c/li\u003e\n \u003cli\u003e Tsumura H, Ichikawa T, Hiyama E, Murakami Y, Sueda T. Systemic inflammatory response syndrome (SIRS) as a predictor of strangulated small bowel obstruction. Hepatogastroenterology. 2004;51:1393-6.\u003c/li\u003e\n \u003cli\u003e Takeuchi K, Tsuzuki Y, Ando T, Sekihara M, Hara T, Yoshikawa M, et al. Clinical studies of strangulating small bowel obstruction. Am Surg. 2004;70:40-4.\u003c/li\u003e\n \u003cli\u003e Kohga A, Kawabe A, Yajima K, Okumura T, Yamashita K, Isogaki J, et al. CT value of the intestine is useful predictor for differentiate irreversible ischaemic changes in strangulated ileus. Abdom Radiol (NY). 2017;42:2816-21.\u0026nbsp;\u003c/li\u003e\n \u003cli\u003e Rondenet C, Millet I, Corno L, Boulay-Coletta I, Taourel P, Zins M. Increased unenhanced bowel-wall attenuation: a specific sign of bowel necrosis in closed-loop small-bowel obstruction. Eur Radiol. 2018;28:4225-33.\u0026nbsp;\u003c/li\u003e\n \u003cli\u003e Makita O, Ikushima I, Matsumoto N, Arikawa K, Yamashita Y, Takahashi M. CT differentiation between necrotic and nonnecrotic small bowel in closed loop and strangulating obstruction. Abdom Imaging. 1999;24:120-4.\u0026nbsp;\u003c/li\u003e\n \u003cli\u003e Kobayashi S, Matsuura K, Matsushima K, Okubo K, Henzan E, Maeshiro M. Effectiveness of diagnostic paracentesis and ascites analysis for suspected strangulation obstruction. J Gastrointest Surg. 2007;11:240-6.\u0026nbsp;\u003c/li\u003e\n \u003cli\u003e Abramowitz Y, Simanovsky N, Goldstein MS, Hiller N. Pleural effusion: characterization with CT attenuation values and CT appearance. AJR Am J Roentgenol. 2009;192:618-23.\u0026nbsp;\u003c/li\u003e\n \u003cli\u003e Federle MP, Jeffrey RB Jr. Hemoperitoneum studied by computed tomography. Radiology. 1983;148:187-92.\u0026nbsp;\u003c/li\u003e\n \u003cli\u003e Matsushima K, Inaba K, Dollbaum R, Cheng V, Khan M, Herr K, et al. High-density free fluid on computed tomography: a predictor of surgical intervention in patients with adhesive small bowel obstruction. J Gastrointest Surg. 2016;20:1861-6. \u003c/li\u003e\n\u003c/ol\u003e\n"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":true,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"bmc-surgery","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"bsur","sideBox":"Learn more about [BMC Surgery](http://bmcsurg.biomedcentral.com/)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/bsur/default.aspx","title":"BMC Surgery","twitterHandle":"@BMC_series","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"em","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"bowel strangulation, intestinal ischemia, prediction, computed tomography, surgical emergency, preoperative diagnosis","lastPublishedDoi":"10.21203/rs.3.rs-1626055/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-1626055/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e\u003cstrong\u003eBackground: \u003c/strong\u003ePreoperatively diagnosing irreversible intestinal ischemia in patients with strangulated bowel obstruction is difficult. Therefore, this study aimed to establish a prediction model for irreversible intestinal ischemia in strangulated bowel obstruction.\u003c/p\u003e\u003cp\u003e\u003cstrong\u003eMethods: \u003c/strong\u003eWe included 83 patients who underwent emergency surgery for strangulated bowel obstruction between January 2014 and March 2022. The predictors of irreversible intestinal ischemia in strangulated bowel obstruction were identified using logistic regression analysis, and a prediction model for irreversible intestinal ischemia in strangulated bowel obstruction was established using the regression coefficients. Receiver operating characteristic analysis and 5-fold cross-validation was used to assess the model.\u003c/p\u003e\u003cp\u003e\u003cstrong\u003eResults: \u003c/strong\u003eThe prediction model (range, 0−4) was established using a white blood cell count of ≥ 12000/µL and the computed tomography value of peritoneal fluid that was ≥ 20 Hounsfield units. The areas of the receiver operating characteristic curve of the new prediction model were 0.814 and 0.807 after 5-fold cross-validation. A score of ≥ 2 was strongly suggestive of irreversible intestinal ischemia in strangulated bowel obstruction and necessitated bowel resection (odds ratio = 15.938). The bowel resection rates for the prediction scores of 0, 2, and 4 were 15.2%, 66.7%, and 85.0%, respectively.\u003c/p\u003e\u003cp\u003e\u003cstrong\u003eConclusions: \u003c/strong\u003eOur model may help predict irreversible intestinal ischemia that necessitates bowel resection for strangulated bowel obstruction cases and thus enable surgeons to recognize the severity of the situation and prepare for deterioration of patients with progression of intestinal ischemia.\u003c/p\u003e","manuscriptTitle":"Prediction Model for Irreversible Intestinal Ischemia in Strangulated Bowel Obstruction","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2022-05-11 17:26:47","doi":"10.21203/rs.3.rs-1626055/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Major revision","date":"2022-07-22T07:49:10+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2022-05-20T18:34:58+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"f7507b92-841f-405a-9bab-29afa6e13e61","date":"2022-05-11T17:25:54+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2022-05-11T14:23:18+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2022-05-11T14:12:49+00:00","index":"","fulltext":""},{"type":"editorInvited","content":"","date":"2022-05-07T15:51:00+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2022-05-07T15:43:01+00:00","index":"","fulltext":""},{"type":"submitted","content":"BMC Surgery","date":"2022-05-05T12:39:45+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"bmc-surgery","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"bsur","sideBox":"Learn more about [BMC Surgery](http://bmcsurg.biomedcentral.com/)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/bsur/default.aspx","title":"BMC Surgery","twitterHandle":"@BMC_series","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"em","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"33b00348-2d02-4d0b-9a73-c71529c82805","owner":[],"postedDate":"May 11th, 2022","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"under-review","subjectAreas":[],"tags":[],"updatedAt":"2022-08-08T08:14:33+00:00","versionOfRecord":[],"versionCreatedAt":"2022-05-11 17:26:47","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-1626055","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-1626055","identity":"rs-1626055","version":["v1"]},"buildId":"7rjqhiLT3MXkJMwkYKINL","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}