Preoperative Risk Factors for 90-day Postoperative Mortality Outcome in Patients With Non-occlusive Mesenteric Ischemia

Preoperative Risk Factors for 90-day Postoperative Mortality Outcome in Patients With Non-occlusive Mesenteric Ischemia | 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 Preoperative Risk Factors for 90-day Postoperative Mortality Outcome in Patients With Non-occlusive Mesenteric Ischemia Makoto Uchino, Daichi Kitaguchi, Kinji Furuya, Yohei Owada, Koichi Ogawa, and 5 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-3812957/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 Purpose The mortality rate of non-occlusive mesenteric ischemia remains despite surviving the acute postoperative period with tremendous treatment efforts, including emergency surgery, which is challenging. This study explored the preoperative risk factors for 90-day postoperative mortality in patients with non-occlusive mesenteric ischemia. Methods This was a single-center retrospective cohort study. Patients diagnosed with non-occlusive mesenteric ischemia who underwent emergency surgery between August 2014 and January 2023 were included in this study. All patients were divided into survival-to-discharge and mortality outcome groups at the 90-day postoperative follow-up. Preoperative factors, including co-morbidities, preoperative status of vital signs and consciousness, blood gas analysis, blood test results, and computed tomography, were compared between the two groups. Results Twenty patients were eligible for this study, and 90-day mortality was observed in 10 patients (50%). The mortality outcome group had significantly lower HCO3- (20.9 vs. 14.6, p = 0.006 ) and higher lactate (4.4 vs. 9.4, p = 0.023 ) compared with the survival outcome group. The median postoperative time to death was 19 [2–69] days, and five patients (50%) died after postoperative day 30, mainly because hemodialysis was discontinued due to hemodynamic instability in patients requiring hemodialysis. Conclusion Low preoperative HCO3- and high lactate levels may be preoperative risk factors for 90-day postoperative mortality in patients with non-occlusive mesenteric ischemia. However, patients on hemodialysis die from discontinuing hemodialysis even after surviving the acute postoperative phase. Hence, indications for emergency surgery in patients with risk factors for postoperative mortality should be carefully determined. Figures Figure 1 Figure 2 Introduction Non-occlusive mesenteric ischemia (NOMI) was first described by Ende in 1958 as necrosis of the small intestine in patients with heart failure [ 1 ]. According to Heer et al., NOMI is defined as the absence of obstruction in the mesenteric arteriovenous system in the area of intestinal necrosis, discontinuity of necrotic and ischemic changes in the intestinal tract, and histopathological findings of bleeding and necrotic changes; however, there is a lack of fibrin thrombus in the small veins [ 2 ]. The incidence of this disease is high in elderly patients with cardiovascular disease, cerebrovascular disease, diabetes, and other underlying diseases, as well as patients with burns and those undergoing hemodialysis (HD) [ 3 , 4 ]; however, the cause of NOMI remains unclear. The mortality rate of patients with NOMI is extremely high, ranging from 56–79%, and the prognosis is poor [ 5 , 6 ]. With surgical intervention, the life-saving rate is approximately 53% [ 7 ]. Although there have been several reports on the risk factors for postoperative mortality in patients with NOMI, there is no consensus, and no clear risk factors have been identified to date. Furthermore, most previous reports have focused only on early postoperative mortality [ 8 ], with only a few reports on mid- to long-term follow-up after survival through the acute postoperative phase. Knowledge of the possibility of mortality not only during the perioperative period but also after survival through the acute postoperative phase is important for making subsequent treatment decisions for both healthcare providers and patients. Therefore, the aim of this study was to conduct a medium-term review of patients with NOMI who underwent surgery, with comparisons between those who were discharged alive and those with mortality outcomes. Additionally, we explored the risk factors for 90-day postoperative mortality in patients with NOMI. Material and Methods Study Design This single-center retrospective cohort study used a prospectively collected clinical database. Informed consent was obtained from all participants by providing them with an opt-out option following the Good Clinical Practice Guidelines of the Ministry of Health and Welfare of Japan [ 9 ]. The study protocol was approved by the ethics committee of the University of Tsukuba Hospital, Ibaraki, Japan (registration number: R04-206). The study conformed to the provisions of the Declaration of Helsinki of 1964 (revised in Brazil in 2013). Patient Selection Patients diagnosed with NOMI based on preoperative computed tomography (CT) who underwent emergency surgery between August 2014 and January 2023 were included in the study. The CT findings used for diagnosis were segmental ischemia or necrosis in the absence of obvious major vessel occlusion, according to the definition reported by Suzuki et al. [ 7 ]. The study involved a medium-term follow-up period, with patients followed for 90 days after the perioperative management period, even if they were transferred from the department of surgery to other departments. All eligible patients were divided into the survival-to-discharge and mortality outcome groups. The survival-to-discharge group included patients with home or nursing facility discharge or transfer from the hospital (excluding death within 90 days after surgery at the transfer site). In contrast, the mortality outcome group included patients who died during hospitalization and those who died within 90 days after surgery at the transfer site. Data Collection The following clinical information was collected from medical records as prognostic factors for the risk of postoperative mortality. Patient information: sex, age, body mass index (BMI), and co-morbidities Preoperative status: mean blood pressure (BP), body temperature, heart rate (HR), respiratory rate (RR), syncope status, and consciousness level Blood gas analysis data: pH, PaCO 2 , PaO 2 , HCO3-, lactate, alveolar arterial oxygen difference (AaDo2), and base excess Blood test data: white blood cell (WBC), hematocrit (Ht), platelets (Plt), creatine kinase (CK), and C-reactive protein (CRP) CT findings: portal vein gas, distribution of necrotic bowel In this study, the mean BP was calculated at the time of preoperative NOMI diagnosis using the following formula: $$Mean BP=\frac{\left(2\times diastolic BP\right)+systolic BP}{3}$$ Data were analyzed for each group to compare preoperative factors related to the outcome at discharge. A flowchart of patient enrollment is displayed in Fig. 1 . Statistical Analyses Numerical data are described as median (range) and were compared using the Mann–Whitney U test. Categorical data are presented as number (percentage) and were compared using Fisher’s exact test. All P-values were two-sided, and the level of significance was set at P < 0.05. All statistical analyses were performed using EZR [ 10 ], a graphical user interface for the R, version 4.2.1 (The R Foundation for Statistical Computing, Vienna, Austria). Results The patient characteristics in each group are presented in Table 1 . Twenty patients were eligible for this study, and each of the survival, discharge, and mortality outcome groups included 10 patients. In the entire cohort, preoperative comorbidities included cardiovascular disease, pulmonary disease, liver failure, renal failure, diabetes mellitus, and cancer in 11, three, one, seven, six, and five patients, respectively. Ten patients were in shock preoperatively, 13 had a preoperative consciousness disorder, seven were on HD, and four used steroids. There were more HD patients in the mortality outcome group than in the survival-to-discharge group (60% vs. 10%). Table 1 Patient characteristics Survival-to-discharge group (N = 10) Mortality outcome group (N = 10) Age (year) 81 [43–87]* 68 [52–85]* Sex Male Female 3 7 5 5 BMI (kg/m²) 21.9 [18.3–31.9]* 22.1 [18.0-38.9]* Comorbidities Cardiovascular disease Pulmonary disease Liver failure Renal failure Diabetes mellitus Cancer Total 5 (50%) 1 (10%) 0 2 (20%) 3 (30%) 0 6 (60%) 6 (60%) 2 (20%) 1 (10%) 6 (60%) 3 (30%) 5 (50%) 8 (80%) Pre-operative status Shock Consciousness disorder 3 (30%) 7 (70%) 7 (70%) 6 (60%) Hemodialysis 1 (10%) 6 (60%) Steroid use 3 (30%) 1 (10%) *Median [range] BMI: body mass index Table 2 indicates the findings of the physical examination, blood gas analysis, blood tests, and CT in each group. CT findings included portal gas and distribution of the necrotic intestinal tract before surgery. The mortality outcome group had significantly lower HCO3- (20.9 vs. 14.6, p = 0.006 ) and higher lactate (4.4 vs. 9.4, p = 0.023 ) than did the patients within the survival-to-discharge group. Table 2 Clinical findings at diagnosis Survival-to-discharge group (N = 10) Mortality outcome group (N = 10) p-value Preoperative status BT (℃) Mean BP (mmHg) HR (/min) RR (/min) 37.2 [35.1–38.0] 75.5 [38–128] 107.5 [58–144] 22.0 [15–36] 36.95 [35.4–40] 61.0 [45–108] 97.0 [70–128) 24.5 [16–32) 0.677 0.111 0.791 0.403 BGA pH PaCO2 (mmHg) PaO2 (mmHg) HCO3- (mmHg) Na (mEq/L) K (mEq/L) Lactate (mmol/L) Base excess AaDo2 7.410 [7.226–7.506] 32.85 [11.0-43.7] 83.3 [64.3–247.0] 20.9 [14.9–22.4] 141.5 [131–157] 4.585 [3.5–5.5] 4.35 [1.4–10.4] -4.75 [(-15.8)-(-0.4)] 80.9 [45.7-398.6] 7.325 [6.963–7.449] 36.1 [15.5–44.0] 133.0 [52.0-303.4] 14.6 [8.4–20.7] 137.5 [128–142] 4.11 [2.4-7.0] 9.4 [2.5–14.9] -9.90 [(-21.8)-(-3.5)] 85.8 [-2.6-478] 0.079 0.400 0.387 0.006 0.225 0.185 0.023 0.079 0.470 Blood tests WBC (/µL) Ht (%) Plt (10⁴/µL) CK (IU/L) CRP (mg/dL) 13200 [6900–37400] 30.7 [23.1–44.1] 21.2 [9.9–33.9] 87 [23-20348] 4.31 [0.03–42.9] 11750 [6000–23300] 30.9 [16.9–45.8] 14.4 [7.6–25.5] 169 [8-3673] 18.9 [6.64–19.2] 0.850 0.739 0.064 0.780 0.052 CT findings portal gas Small bowel necrosis 5 (50%) 7 (70%) 1 (10%) 8 (80%) 0.141 1.000 Median [range] BT: body temperature, BP: blood pressure, HR: heart rate, RR: respiration rate, BGA: blood gas analysis, AaDo2: alveolar arterial oxygen difference, CT: computed tomography, WBC: white blood cell, Ht: hematocrit, Plt: platelet, CK: creatine kinase, CRP: C-reactive protein The causes of mortality, listed in Table 3 , included multiorgan failure due to septic shock in six patients and inability to continue HD due to hemodynamic instability in four patients. The median time to death was 19 [2–69] days. Five patients survived the acute postoperative phase but had a fatal outcome > 30 days after surgery. Table 3 Characteristics of 10 patients with postoperative mortality outcomes Comorbidities Postoperative Survival (days) Cause of death Cardiovascular disease Pulmonary disease Cancer Renal failure Liver failure ● ● 2 Septic shock ● ● 3 Septic shock ● ● 4 Septic shock ● ● 11 Septic shock ● 18 Septic shock ● ● 19 Septic shock ● ● 37 Unable to continue HD ● ● 45 Unable to continue HD ● ● 47 Septic shock ● ● 69 Unable to continue HD Discussion This study summarized the short- and mid-term outcomes of 20 patients with NOMI who underwent emergency surgery; we found that 50% patients did not survive. Low HCO3- and high lactate levels may be preoperative risk factors for mortality. Six of these patients died in the early postoperative period within 30 days after surgery because of septic shock; however, the remaining four patients died because of septic shock or were unable to continue HD despite surviving the acute postoperative period. These results suggest that patients on HD, even if they avoid early postoperative death, have a high risk of postoperative mortality because they are unable to continue HD. The indications for surgery in patients with these risk factors should be carefully evaluated. The concept of NOMI includes acute mesenteric ischemia (AMI), occlusive mesenteric arterial ischemia (OMI), and mesenteric venous thrombosis (MVT) [ 11 ]; NOMI was found to occur in 20–30% AMI cases in previous reports [ 5 , 12 ]. According to previous reports, physiological findings of NOMI include elevations in aspartate aminotransferase (AST), alanine aminotransferase (ALT), creatine phosphorus kinase (CPK), and lactate dehydrogenase (LDH), as well as lactic acidosis and metabolic acidosis without an elevated inflammatory response [ 13 ]; however, these indicate a generalized poor general condition of the patient and lack of specific clinical physiological findings. Although the pathogenic mechanism of NOMI has not been elucidated, it is believed to be caused by endogenous vasopressin and angiotensin secreted to maintain the blood supply to vital organs when systemic perfusion is reduced due to heart failure, shock, or dehydration, resulting in decreased intestinal blood flow [ 14 – 16 ]. Several prognostic factors for NOMI have been reported. Kvarstein et al. reported a base excess decrease with increasing lactate and H⁺ in arterial blood gas analysis and discovered an increase in arteriovenous lactate in a major area of the gut and a decrease in arteriovenous lactate in skeletal muscle due to supply dependency [ 17 ]. In the present study, we observed a similar increase in lactate, reflecting intestinal ischemia, and a decrease in HCO3- due to associated metabolic acidosis. The mortality rate increased with the lactate level; this reflects extensive or irreversible ischemia of the intestinal tract and systemic ischemia involving other organs, which may be a high-risk factor for postoperative mortality. Recently, Suzuki et al. stated that the mean BP (< 68.2 mmHg) and base excess ( < − 4.95 mmol/dL) were poor prognostic factors [ 7 ]. In this study, a low mean BP was not found to be a significant risk factor for postoperative mortality because of the small sample size; however, a trend was observed. Furthermore, we noted that patients with HD had postoperative mortality outcomes, especially after the acute postoperative phase. We divided the HD and non-HD patients and examined mortality based on whether the necrotic intestine was confined to the colon or colonized in the small bowel in HD patients and lactate levels in non-HD patients (Fig. 2 ). All five patients on HD who showed necrosis of the small intestine with or without the colon, rather than necrosis of the colon alone, had a fatal outcome, suggesting that the distribution of the necrotic intestine (i.e., when the necrosis extends into the small intestine) is a prognostic factor in patients on HD. In non-HD patients, when 6.5 mmol/L was used as the cut-off for lactate, four and nine patients showed lactate levels of > 6.5 mmol/L and 6.5 mmol/L had a mortality outcome, while all those with lactate < 6.5 mmol/L were discharged alive. This study has several limitations. First, it was a single-center retrospective study with a small number of cases. Therefore, a few biases and confounding factors could not be eliminated, and the statistical power was insufficient. Second, only surgical cases were collected; thus, cases where surgery was not performed after diagnosis were not included, resulting in underestimation of mortality. Third, patients treated with drugs such as intravenous papaverine hydrochloride without any surgery were not analyzed. Conclusions In summary, 50% patients with NOMI died despite undergoing emergent surgery. Low preoperative HCO3- and high lactate levels may be used as preoperative predictors of mortality in these patients. Moreover, patients on HD showed a tendency for nonsurvival because they were unable to continue HD within 90 days after surgery, even if they survived for the first 30 days after surgery. Therefore, patients with suggested preoperative risk factors for postoperative mortality should be carefully evaluated for emergent surgery. Declarations Conflict of Interest The authors declare that they have no conflict of interest. Funding This study was supported in part by JSPS KAKENHI (grant number: JP23K17185). Ethics Approval This retrospective chart review study involving human participants was in accordance with the ethical standards of the institutional and national research committee and with the 1964 Helsinki Declaration and its later amendments or comparable ethical standards. The study protocol was approved by the Ethics Committee of the University of Tsukuba Hospital, Ibaraki, Japan (registration number: R04-206). Consent to Participate Informed consent was obtained from all participants by providing them with an opt-out option following the Good Clinical Practice Guidelines of the Ministry of Health and Welfare of Japan. Consent to Publish Not applicable. Data Availability Statement The datasets used and/or analyzed in the present study are available from the corresponding author on reasonable request. The corresponding author had full access to all the data in the study and takes responsibility for the integrity of the data and the accuracy of the data analysis. References Ende N (1958) Infarction of the bowel in cardiac failure. N Engl J Med 258:879–881. https://doi.org/10.1056/NEJM195805012581804 Heer FW, Silen W, French SW (2002) Intestinal gangrene without apparent vascular occlusion. Am J Surg 110:231–238. https://doi.org/10.1016/0002-9610(65)90017-6 Trompeter M, Brazda T, Remy CT, Vestring T, Reimer P (2002) Non-occlusive mesenteric ischemia: etiology, diagnosis, and interventional therapy. Eur Radiol 12:1179–1187. https://doi.org/10.1007/s00330-001-1220-2 Stöckmann H, Roblick UJ, Kluge N, et al (2000) Diagnosis and therapy of non-occlusive mesenteric ischemia (NOMI). Zentralbl Chir 125:144–151. 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AJR Am J Roentgenol 192:408–416. https://doi.org/10.2214/AJR.08.1138 Lundgren O, Haglund U (1978) The pathophysiology of the intestinal countercurrent exchanger. Life Sci 23:1411–1422. https://doi.org/10.1016/0024-3205(78)90122-4 Kvarstein G, Mirtaheri P, Tønnessen TI (2033) Detection of organ ischemia during hemorrhagic shock. Acta Anaesthesiol Scand 47:675–686. https://doi.org/10.1034/j.1399-6576.2003.00134.x Additional Declarations No competing interests reported. Cite Share Download PDF Status: Under Review Version 1 posted Editorial decision: Revision requested 02 Feb, 2024 Reviews received at journal 09 Jan, 2024 Reviewers agreed at journal 08 Jan, 2024 Reviewers agreed at journal 08 Jan, 2024 Reviewers invited by journal 08 Jan, 2024 Editor assigned by journal 04 Jan, 2024 Submission checks completed at journal 03 Jan, 2024 First submitted to journal 27 Dec, 2023 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. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-3812957","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":265249533,"identity":"9e207c39-bf3f-4b41-b3b9-3d346f8ce78e","order_by":0,"name":"Makoto Uchino","email":"","orcid":"","institution":"University of Tsukuba Hospital","correspondingAuthor":false,"prefix":"","firstName":"Makoto","middleName":"","lastName":"Uchino","suffix":""},{"id":265249535,"identity":"747bc575-0d5c-488d-862c-d431db1dace1","order_by":1,"name":"Daichi 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enrollment\u003c/p\u003e\n\u003cp\u003eNOMI, non-occlusive mesenteric ischemia\u003c/p\u003e\n\u003cp\u003eCT, computed tomography\u003c/p\u003e\n\u003cp\u003eBT, body temperature\u003c/p\u003e\n\u003cp\u003eBP, blood pressure\u003c/p\u003e\n\u003cp\u003eHR, heart rate\u003c/p\u003e\n\u003cp\u003eRR, respiration rate\u003c/p\u003e\n\u003cp\u003eBGA, blood gas analysis\u003c/p\u003e\n\u003cp\u003eAaDo2, alveolar arterial oxygen difference\u003c/p\u003e\n\u003cp\u003eWBC, white blood cells\u003c/p\u003e\n\u003cp\u003eHt, hematocrit\u003c/p\u003e\n\u003cp\u003ePlt, platelets\u003c/p\u003e\n\u003cp\u003eCK, creatin kinase\u003c/p\u003e\n\u003cp\u003eCRP, c-reactive protein\u003c/p\u003e","description":"","filename":"1.png","url":"https://assets-eu.researchsquare.com/files/rs-3812957/v1/3291ba15fbbb9c9ed1578b5e.png"},{"id":49239143,"identity":"8b7a0e04-e007-41de-a4b5-9c9f22a35184","added_by":"auto","created_at":"2024-01-05 18:14:54","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":120768,"visible":true,"origin":"","legend":"\u003cp\u003ePreoperative risk calculator for postoperative mortality in patients with NOMI\u003c/p\u003e\n\u003cp\u003eNOMI, non-occlusive mesenteric ischemia\u003c/p\u003e","description":"","filename":"2.png","url":"https://assets-eu.researchsquare.com/files/rs-3812957/v1/3569fbcb8b4d327a72c302d0.png"},{"id":49240786,"identity":"a661d25e-4dad-4630-8e01-d1ca4af3e4ad","added_by":"auto","created_at":"2024-01-05 18:22:55","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":558897,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-3812957/v1/046084b7-6c78-4bf5-a6f9-1910b0ee7f94.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Preoperative Risk Factors for 90-day Postoperative Mortality Outcome in Patients With Non-occlusive Mesenteric Ischemia","fulltext":[{"header":"Introduction","content":"\u003cp\u003eNon-occlusive mesenteric ischemia (NOMI) was first described by Ende in 1958 as necrosis of the small intestine in patients with heart failure [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e]. According to Heer et al., NOMI is defined as the absence of obstruction in the mesenteric arteriovenous system in the area of intestinal necrosis, discontinuity of necrotic and ischemic changes in the intestinal tract, and histopathological findings of bleeding and necrotic changes; however, there is a lack of fibrin thrombus in the small veins [\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e]. The incidence of this disease is high in elderly patients with cardiovascular disease, cerebrovascular disease, diabetes, and other underlying diseases, as well as patients with burns and those undergoing hemodialysis (HD) [\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e, \u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e]; however, the cause of NOMI remains unclear.\u003c/p\u003e \u003cp\u003eThe mortality rate of patients with NOMI is extremely high, ranging from 56\u0026ndash;79%, and the prognosis is poor [\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e, \u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e]. With surgical intervention, the life-saving rate is approximately 53% [\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e]. Although there have been several reports on the risk factors for postoperative mortality in patients with NOMI, there is no consensus, and no clear risk factors have been identified to date. Furthermore, most previous reports have focused only on early postoperative mortality [\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e], with only a few reports on mid- to long-term follow-up after survival through the acute postoperative phase.\u003c/p\u003e \u003cp\u003eKnowledge of the possibility of mortality not only during the perioperative period but also after survival through the acute postoperative phase is important for making subsequent treatment decisions for both healthcare providers and patients. Therefore, the aim of this study was to conduct a medium-term review of patients with NOMI who underwent surgery, with comparisons between those who were discharged alive and those with mortality outcomes. Additionally, we explored the risk factors for 90-day postoperative mortality in patients with NOMI.\u003c/p\u003e"},{"header":"Material and Methods","content":"\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e \u003ch2\u003eStudy Design\u003c/h2\u003e \u003cp\u003eThis single-center retrospective cohort study used a prospectively collected clinical database. Informed consent was obtained from all participants by providing them with an opt-out option following the Good Clinical Practice Guidelines of the Ministry of Health and Welfare of Japan [\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e]. The study protocol was approved by the ethics committee of the University of Tsukuba Hospital, Ibaraki, Japan (registration number: R04-206). The study conformed to the provisions of the Declaration of Helsinki of 1964 (revised in Brazil in 2013).\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec4\" class=\"Section2\"\u003e \u003ch2\u003ePatient Selection\u003c/h2\u003e \u003cp\u003ePatients diagnosed with NOMI based on preoperative computed tomography (CT) who underwent emergency surgery between August 2014 and January 2023 were included in the study. The CT findings used for diagnosis were segmental ischemia or necrosis in the absence of obvious major vessel occlusion, according to the definition reported by Suzuki et al. [\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e]. The study involved a medium-term follow-up period, with patients followed for 90 days after the perioperative management period, even if they were transferred from the department of surgery to other departments. All eligible patients were divided into the survival-to-discharge and mortality outcome groups. The survival-to-discharge group included patients with home or nursing facility discharge or transfer from the hospital (excluding death within 90 days after surgery at the transfer site). In contrast, the mortality outcome group included patients who died during hospitalization and those who died within 90 days after surgery at the transfer site.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec5\" class=\"Section2\"\u003e \u003ch2\u003eData Collection\u003c/h2\u003e \u003cp\u003eThe following clinical information was collected from medical records as prognostic factors for the risk of postoperative mortality.\u003c/p\u003e \u003cp\u003e \u003cul\u003e \u003cli\u003e \u003cp\u003ePatient information: sex, age, body mass index (BMI), and co-morbidities\u003c/p\u003e \u003c/li\u003e \u003cli\u003e \u003cp\u003ePreoperative status: mean blood pressure (BP), body temperature, heart rate (HR), respiratory rate (RR), syncope status, and consciousness level\u003c/p\u003e \u003c/li\u003e \u003cli\u003e \u003cp\u003eBlood gas analysis data: pH, PaCO\u003csub\u003e2\u003c/sub\u003e, PaO\u003csub\u003e2\u003c/sub\u003e, HCO3-, lactate, alveolar arterial oxygen difference (AaDo2), and base excess\u003c/p\u003e \u003c/li\u003e \u003cli\u003e \u003cp\u003eBlood test data: white blood cell (WBC), hematocrit (Ht), platelets (Plt), creatine kinase (CK), and C-reactive protein (CRP)\u003c/p\u003e \u003c/li\u003e \u003cli\u003e \u003cp\u003eCT findings: portal vein gas, distribution of necrotic bowel\u003c/p\u003e \u003c/li\u003e \u003c/ul\u003e \u003c/p\u003e \u003cp\u003eIn this study, the mean BP was calculated at the time of preoperative NOMI diagnosis using the following formula:\u003cdiv id=\"Equa\" class=\"Equation\"\u003e\u003cdiv format=\"TEX\" class=\"mathdisplay\" id=\"FileID_Equa\" name=\"EquationSource\"\u003e\n$$Mean BP=\\frac{\\left(2\\times diastolic BP\\right)+systolic BP}{3}$$\u003c/div\u003e\u003c/div\u003e\u003c/p\u003e \u003cp\u003eData were analyzed for each group to compare preoperative factors related to the outcome at discharge. A flowchart of patient enrollment is displayed in Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec6\" class=\"Section2\"\u003e \u003ch2\u003eStatistical Analyses\u003c/h2\u003e \u003cp\u003eNumerical data are described as median (range) and were compared using the Mann\u0026ndash;Whitney \u003cem\u003eU\u003c/em\u003e test. Categorical data are presented as number (percentage) and were compared using Fisher\u0026rsquo;s exact test. All P-values were two-sided, and the level of significance was set at \u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.05. All statistical analyses were performed using EZR [\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e], a graphical user interface for the R, version 4.2.1 (The R Foundation for Statistical Computing, Vienna, Austria).\u003c/p\u003e \u003c/div\u003e"},{"header":"Results","content":"\u003cp\u003eThe patient characteristics in each group are presented in Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e. Twenty patients were eligible for this study, and each of the survival, discharge, and mortality outcome groups included 10 patients. In the entire cohort, preoperative comorbidities included cardiovascular disease, pulmonary disease, liver failure, renal failure, diabetes mellitus, and cancer in 11, three, one, seven, six, and five patients, respectively. Ten patients were in shock preoperatively, 13 had a preoperative consciousness disorder, seven were on HD, and four used steroids. There were more HD patients in the mortality outcome group than in the survival-to-discharge group (60% vs. 10%).\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\u003ePatient characteristics\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\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eSurvival-to-discharge group\u003c/p\u003e \u003cp\u003e(N\u0026thinsp;=\u0026thinsp;10)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eMortality outcome group\u003c/p\u003e \u003cp\u003e(N\u0026thinsp;=\u0026thinsp;10)\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAge (year)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e81 [43\u0026ndash;87]*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e68 [52\u0026ndash;85]*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSex\u003c/p\u003e \u003cp\u003eMale\u003c/p\u003e \u003cp\u003eFemale\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e3\u003c/p\u003e \u003cp\u003e7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e5\u003c/p\u003e \u003cp\u003e5\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eBMI (kg/m\u0026sup2;)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e21.9 [18.3\u0026ndash;31.9]*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e22.1 [18.0-38.9]*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eComorbidities\u003c/p\u003e \u003cp\u003eCardiovascular disease\u003c/p\u003e \u003cp\u003ePulmonary disease\u003c/p\u003e \u003cp\u003eLiver failure\u003c/p\u003e \u003cp\u003eRenal failure\u003c/p\u003e \u003cp\u003eDiabetes mellitus\u003c/p\u003e \u003cp\u003eCancer\u003c/p\u003e \u003cp\u003eTotal\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e5 (50%)\u003c/p\u003e \u003cp\u003e1 (10%)\u003c/p\u003e \u003cp\u003e0\u003c/p\u003e \u003cp\u003e2 (20%)\u003c/p\u003e \u003cp\u003e3 (30%)\u003c/p\u003e \u003cp\u003e0\u003c/p\u003e \u003cp\u003e6 (60%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e6 (60%)\u003c/p\u003e \u003cp\u003e2 (20%)\u003c/p\u003e \u003cp\u003e1 (10%)\u003c/p\u003e \u003cp\u003e6 (60%)\u003c/p\u003e \u003cp\u003e3 (30%)\u003c/p\u003e \u003cp\u003e5 (50%)\u003c/p\u003e \u003cp\u003e8 (80%)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePre-operative status\u003c/p\u003e \u003cp\u003eShock\u003c/p\u003e \u003cp\u003eConsciousness disorder\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e3 (30%)\u003c/p\u003e \u003cp\u003e7 (70%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e7 (70%)\u003c/p\u003e \u003cp\u003e6 (60%)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eHemodialysis\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1 (10%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e6 (60%)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSteroid use\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e3 (30%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1 (10%)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"3\"\u003e*Median [range]\u003c/td\u003e\u003c/tr\u003e \u003ctr\u003e\u003ctd colspan=\"3\"\u003eBMI: body mass index\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003eTable\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e indicates the findings of the physical examination, blood gas analysis, blood tests, and CT in each group. CT findings included portal gas and distribution of the necrotic intestinal tract before surgery. The mortality outcome group had significantly lower HCO3- (20.9 vs. 14.6, \u003cem\u003ep\u0026thinsp;=\u0026thinsp;0.006\u003c/em\u003e) and higher lactate (4.4 vs. 9.4, \u003cem\u003ep\u0026thinsp;=\u0026thinsp;0.023\u003c/em\u003e) than did the patients within the survival-to-discharge group.\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\u003eClinical findings at diagnosis\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\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eSurvival-to-discharge group\u003c/p\u003e \u003cp\u003e(N\u0026thinsp;=\u0026thinsp;10)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eMortality outcome group\u003c/p\u003e \u003cp\u003e(N\u0026thinsp;=\u0026thinsp;10)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u003cem\u003ep-value\u003c/em\u003e\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePreoperative status\u003c/p\u003e \u003cp\u003eBT (℃)\u003c/p\u003e \u003cp\u003eMean BP (mmHg)\u003c/p\u003e \u003cp\u003eHR (/min)\u003c/p\u003e \u003cp\u003eRR (/min)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e37.2 [35.1\u0026ndash;38.0]\u003c/p\u003e \u003cp\u003e75.5 [38\u0026ndash;128]\u003c/p\u003e \u003cp\u003e107.5 [58\u0026ndash;144]\u003c/p\u003e \u003cp\u003e22.0 [15\u0026ndash;36]\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e36.95 [35.4\u0026ndash;40]\u003c/p\u003e \u003cp\u003e61.0 [45\u0026ndash;108]\u003c/p\u003e \u003cp\u003e97.0 [70\u0026ndash;128)\u003c/p\u003e \u003cp\u003e24.5 [16\u0026ndash;32)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u003cem\u003e0.677\u003c/em\u003e\u003c/p\u003e \u003cp\u003e\u003cem\u003e0.111\u003c/em\u003e\u003c/p\u003e \u003cp\u003e\u003cem\u003e0.791\u003c/em\u003e\u003c/p\u003e \u003cp\u003e\u003cem\u003e0.403\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eBGA\u003c/p\u003e \u003cp\u003epH\u003c/p\u003e \u003cp\u003ePaCO2 (mmHg)\u003c/p\u003e \u003cp\u003ePaO2 (mmHg)\u003c/p\u003e \u003cp\u003eHCO3- (mmHg)\u003c/p\u003e \u003cp\u003eNa (mEq/L)\u003c/p\u003e \u003cp\u003eK (mEq/L)\u003c/p\u003e \u003cp\u003eLactate (mmol/L)\u003c/p\u003e \u003cp\u003eBase excess\u003c/p\u003e \u003cp\u003eAaDo2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e7.410 [7.226\u0026ndash;7.506]\u003c/p\u003e \u003cp\u003e32.85 [11.0-43.7]\u003c/p\u003e \u003cp\u003e83.3 [64.3\u0026ndash;247.0]\u003c/p\u003e \u003cp\u003e20.9 [14.9\u0026ndash;22.4]\u003c/p\u003e \u003cp\u003e141.5 [131\u0026ndash;157]\u003c/p\u003e \u003cp\u003e4.585 [3.5\u0026ndash;5.5]\u003c/p\u003e \u003cp\u003e4.35 [1.4\u0026ndash;10.4]\u003c/p\u003e \u003cp\u003e-4.75 [(-15.8)-(-0.4)]\u003c/p\u003e \u003cp\u003e80.9 [45.7-398.6]\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e7.325 [6.963\u0026ndash;7.449]\u003c/p\u003e \u003cp\u003e36.1 [15.5\u0026ndash;44.0]\u003c/p\u003e \u003cp\u003e133.0 [52.0-303.4]\u003c/p\u003e \u003cp\u003e14.6 [8.4\u0026ndash;20.7]\u003c/p\u003e \u003cp\u003e137.5 [128\u0026ndash;142]\u003c/p\u003e \u003cp\u003e4.11 [2.4-7.0]\u003c/p\u003e \u003cp\u003e9.4 [2.5\u0026ndash;14.9]\u003c/p\u003e \u003cp\u003e-9.90 [(-21.8)-(-3.5)]\u003c/p\u003e \u003cp\u003e85.8 [-2.6-478]\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u003cem\u003e0.079\u003c/em\u003e\u003c/p\u003e \u003cp\u003e\u003cem\u003e0.400\u003c/em\u003e\u003c/p\u003e \u003cp\u003e\u003cem\u003e0.387\u003c/em\u003e\u003c/p\u003e \u003cp\u003e\u003cem\u003e0.006\u003c/em\u003e\u003c/p\u003e \u003cp\u003e\u003cem\u003e0.225\u003c/em\u003e\u003c/p\u003e \u003cp\u003e\u003cem\u003e0.185\u003c/em\u003e\u003c/p\u003e \u003cp\u003e\u003cem\u003e0.023\u003c/em\u003e\u003c/p\u003e \u003cp\u003e\u003cem\u003e0.079\u003c/em\u003e\u003c/p\u003e \u003cp\u003e\u003cem\u003e0.470\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eBlood tests\u003c/p\u003e \u003cp\u003eWBC (/\u0026micro;L)\u003c/p\u003e \u003cp\u003eHt (%)\u003c/p\u003e \u003cp\u003ePlt (10⁴/\u0026micro;L)\u003c/p\u003e \u003cp\u003eCK (IU/L)\u003c/p\u003e \u003cp\u003eCRP (mg/dL)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e13200 [6900\u0026ndash;37400]\u003c/p\u003e \u003cp\u003e30.7 [23.1\u0026ndash;44.1]\u003c/p\u003e \u003cp\u003e21.2 [9.9\u0026ndash;33.9]\u003c/p\u003e \u003cp\u003e87 [23-20348]\u003c/p\u003e \u003cp\u003e4.31 [0.03\u0026ndash;42.9]\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e11750 [6000\u0026ndash;23300]\u003c/p\u003e \u003cp\u003e30.9 [16.9\u0026ndash;45.8]\u003c/p\u003e \u003cp\u003e14.4 [7.6\u0026ndash;25.5]\u003c/p\u003e \u003cp\u003e169 [8-3673]\u003c/p\u003e \u003cp\u003e18.9 [6.64\u0026ndash;19.2]\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u003cem\u003e0.850\u003c/em\u003e\u003c/p\u003e \u003cp\u003e\u003cem\u003e0.739\u003c/em\u003e\u003c/p\u003e \u003cp\u003e\u003cem\u003e0.064\u003c/em\u003e\u003c/p\u003e \u003cp\u003e\u003cem\u003e0.780\u003c/em\u003e\u003c/p\u003e \u003cp\u003e\u003cem\u003e0.052\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCT findings\u003c/p\u003e \u003cp\u003eportal gas\u003c/p\u003e \u003cp\u003eSmall bowel necrosis\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e5 (50%)\u003c/p\u003e \u003cp\u003e7 (70%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1 (10%)\u003c/p\u003e \u003cp\u003e8 (80%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u003cem\u003e0.141\u003c/em\u003e\u003c/p\u003e \u003cp\u003e\u003cem\u003e1.000\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"4\"\u003eMedian [range]\u003c/td\u003e\u003c/tr\u003e \u003ctr\u003e\u003ctd colspan=\"4\"\u003eBT: body temperature, BP: blood pressure, HR: heart rate, RR: respiration rate, BGA: blood gas analysis, AaDo2: alveolar arterial oxygen difference, CT: computed tomography, WBC: white blood cell, Ht: hematocrit, Plt: platelet, CK: creatine kinase, CRP: C-reactive protein\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003eThe causes of mortality, listed in Table\u0026nbsp;\u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e, included multiorgan failure due to septic shock in six patients and inability to continue HD due to hemodynamic instability in four patients. The median time to death was 19 [2\u0026ndash;69] days. Five patients survived the acute postoperative phase but had a fatal outcome\u0026thinsp;\u0026gt;\u0026thinsp;30 days after surgery.\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\u003eCharacteristics of 10 patients with postoperative mortality outcomes\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=\"char\" char=\".\" 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\" colspan=\"5\" nameend=\"c5\" namest=\"c1\"\u003e \u003cp\u003eComorbidities\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c6\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003ePostoperative Survival\u003c/p\u003e \u003cp\u003e(days)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c7\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eCause of death\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCardiovascular disease\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003ePulmonary disease\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eCancer\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eRenal failure\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003eLiver failure\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\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 \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e●\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eSeptic shock\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e●\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 \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eSeptic shock\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e●\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e●\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eSeptic shock\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\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 \u003cp\u003e●\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e11\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eSeptic shock\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\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 \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e18\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eSeptic shock\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\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 \u003cp\u003e●\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e19\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eSeptic shock\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e●\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e●\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e37\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eUnable to continue HD\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\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 \u003cp\u003e●\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e45\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eUnable to continue HD\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e●\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 \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e47\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eSeptic shock\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\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 \u003cp\u003e●\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e69\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eUnable to continue HD\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eThis study summarized the short- and mid-term outcomes of 20 patients with NOMI who underwent emergency surgery; we found that 50% patients did not survive. Low HCO3- and high lactate levels may be preoperative risk factors for mortality. Six of these patients died in the early postoperative period within 30 days after surgery because of septic shock; however, the remaining four patients died because of septic shock or were unable to continue HD despite surviving the acute postoperative period. These results suggest that patients on HD, even if they avoid early postoperative death, have a high risk of postoperative mortality because they are unable to continue HD. The indications for surgery in patients with these risk factors should be carefully evaluated.\u003c/p\u003e \u003cp\u003eThe concept of NOMI includes acute mesenteric ischemia (AMI), occlusive mesenteric arterial ischemia (OMI), and mesenteric venous thrombosis (MVT) [\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e]; NOMI was found to occur in 20\u0026ndash;30% AMI cases in previous reports [\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e, \u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e]. According to previous reports, physiological findings of NOMI include elevations in aspartate aminotransferase (AST), alanine aminotransferase (ALT), creatine phosphorus kinase (CPK), and lactate dehydrogenase (LDH), as well as lactic acidosis and metabolic acidosis without an elevated inflammatory response [\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e]; however, these indicate a generalized poor general condition of the patient and lack of specific clinical physiological findings. Although the pathogenic mechanism of NOMI has not been elucidated, it is believed to be caused by endogenous vasopressin and angiotensin secreted to maintain the blood supply to vital organs when systemic perfusion is reduced due to heart failure, shock, or dehydration, resulting in decreased intestinal blood flow [\u003cspan additionalcitationids=\"CR15\" citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eSeveral prognostic factors for NOMI have been reported. Kvarstein et al. reported a base excess decrease with increasing lactate and H⁺ in arterial blood gas analysis and discovered an increase in arteriovenous lactate in a major area of the gut and a decrease in arteriovenous lactate in skeletal muscle due to supply dependency [\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e]. In the present study, we observed a similar increase in lactate, reflecting intestinal ischemia, and a decrease in HCO3- due to associated metabolic acidosis. The mortality rate increased with the lactate level; this reflects extensive or irreversible ischemia of the intestinal tract and systemic ischemia involving other organs, which may be a high-risk factor for postoperative mortality. Recently, Suzuki et al. stated that the mean BP (\u0026lt;\u0026thinsp;68.2 mmHg) and base excess (\u0026thinsp;\u0026lt;\u0026thinsp;\u0026minus;\u0026thinsp;4.95 mmol/dL) were poor prognostic factors [\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e]. In this study, a low mean BP was not found to be a significant risk factor for postoperative mortality because of the small sample size; however, a trend was observed.\u003c/p\u003e \u003cp\u003eFurthermore, we noted that patients with HD had postoperative mortality outcomes, especially after the acute postoperative phase. We divided the HD and non-HD patients and examined mortality based on whether the necrotic intestine was confined to the colon or colonized in the small bowel in HD patients and lactate levels in non-HD patients (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e). All five patients on HD who showed necrosis of the small intestine with or without the colon, rather than necrosis of the colon alone, had a fatal outcome, suggesting that the distribution of the necrotic intestine (i.e., when the necrosis extends into the small intestine) is a prognostic factor in patients on HD. In non-HD patients, when 6.5 mmol/L was used as the cut-off for lactate, four and nine patients showed lactate levels of \u0026gt;\u0026thinsp;6.5 mmol/L and \u0026lt;\u0026thinsp;6.5 mmol/L, respectively. All patients with lactate\u0026thinsp;\u0026gt;\u0026thinsp;6.5 mmol/L had a mortality outcome, while all those with lactate\u0026thinsp;\u0026lt;\u0026thinsp;6.5 mmol/L were discharged alive.\u003c/p\u003e \u003cp\u003eThis study has several limitations. First, it was a single-center retrospective study with a small number of cases. Therefore, a few biases and confounding factors could not be eliminated, and the statistical power was insufficient. Second, only surgical cases were collected; thus, cases where surgery was not performed after diagnosis were not included, resulting in underestimation of mortality. Third, patients treated with drugs such as intravenous papaverine hydrochloride without any surgery were not analyzed.\u003c/p\u003e"},{"header":"Conclusions","content":"\u003cp\u003eIn summary, 50% patients with NOMI died despite undergoing emergent surgery. Low preoperative HCO3- and high lactate levels may be used as preoperative predictors of mortality in these patients. Moreover, patients on HD showed a tendency for nonsurvival because they were unable to continue HD within 90 days after surgery, even if they survived for the first 30 days after surgery. Therefore, patients with suggested preoperative risk factors for postoperative mortality should be carefully evaluated for emergent surgery.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003eConflict of Interest\u0026nbsp;\u003c/p\u003e\n\n\u003cp\u003eThe authors declare that they have no conflict of interest.\u003c/p\u003e\n\n\u003cp\u003eFunding\u003c/p\u003e\n\n\u003cp\u003eThis study was supported in part by JSPS KAKENHI (grant number: JP23K17185).\u0026nbsp;\u003c/p\u003e\n\n\u003cp\u003eEthics Approval\u003c/p\u003e\n\n\u003cp\u003eThis retrospective chart review study involving human participants was in accordance with the ethical standards of the institutional and national research committee and with the 1964 Helsinki Declaration and its later amendments or comparable ethical standards. The study protocol was approved by the Ethics Committee of the University of Tsukuba Hospital, Ibaraki, Japan (registration number: R04-206).\u003c/p\u003e\n\n\u003cp\u003eConsent to Participate\u003c/p\u003e\n\n\u003cp\u003eInformed consent was obtained from all participants by providing them with an opt-out option following the Good Clinical Practice Guidelines of the Ministry of Health and Welfare of Japan.\u003c/p\u003e\n\n\u003cp\u003eConsent to Publish\u003c/p\u003e\n\n\u003cp\u003eNot applicable.\u003c/p\u003e\n\n\u003cp\u003eData Availability Statement\u0026nbsp;\u003c/p\u003e\n\n\u003cp\u003eThe datasets used and/or analyzed in the present study are available from the corresponding author on reasonable request. The corresponding author had full access to all the data in the study and takes responsibility for the integrity of the data and the accuracy of the data analysis.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eEnde N (1958) Infarction of the bowel in cardiac failure. N Engl J Med 258:879\u0026ndash;881. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1056/NEJM195805012581804\u003c/span\u003e\u003cspan address=\"10.1056/NEJM195805012581804\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eHeer FW, Silen W, French SW (2002) Intestinal gangrene without apparent vascular occlusion. 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Acta Anaesthesiol Scand 47:675\u0026ndash;686. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1034/j.1399-6576.2003.00134.x\u003c/span\u003e\u003cspan address=\"10.1034/j.1399-6576.2003.00134.x\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e\u003c/ol\u003e"}],"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":"langenbecks-archives-of-surgery","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"laos","sideBox":"Learn more about [Langenbeck's Archives of Surgery](http://link.springer.com/journal/423)","snPcode":"423","submissionUrl":"https://submission.nature.com/new-submission/423/3","title":"Langenbeck's Archives of Surgery","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false},"keywords":"","lastPublishedDoi":"10.21203/rs.3.rs-3812957/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-3812957/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003ch2\u003ePurpose\u003c/h2\u003e \u003cp\u003eThe mortality rate of non-occlusive mesenteric ischemia remains despite surviving the acute postoperative period with tremendous treatment efforts, including emergency surgery, which is challenging. This study explored the preoperative risk factors for 90-day postoperative mortality in patients with non-occlusive mesenteric ischemia.\u003c/p\u003e\u003ch2\u003eMethods\u003c/h2\u003e \u003cp\u003eThis was a single-center retrospective cohort study. Patients diagnosed with non-occlusive mesenteric ischemia who underwent emergency surgery between August 2014 and January 2023 were included in this study. All patients were divided into survival-to-discharge and mortality outcome groups at the 90-day postoperative follow-up. Preoperative factors, including co-morbidities, preoperative status of vital signs and consciousness, blood gas analysis, blood test results, and computed tomography, were compared between the two groups.\u003c/p\u003e\u003ch2\u003eResults\u003c/h2\u003e \u003cp\u003eTwenty patients were eligible for this study, and 90-day mortality was observed in 10 patients (50%). The mortality outcome group had significantly lower HCO3- (20.9 vs. 14.6, \u003cem\u003ep\u0026thinsp;=\u0026thinsp;0.006\u003c/em\u003e) and higher lactate (4.4 vs. 9.4, \u003cem\u003ep\u0026thinsp;=\u0026thinsp;0.023\u003c/em\u003e) compared with the survival outcome group. The median postoperative time to death was 19 [2\u0026ndash;69] days, and five patients (50%) died after postoperative day 30, mainly because hemodialysis was discontinued due to hemodynamic instability in patients requiring hemodialysis.\u003c/p\u003e\u003ch2\u003eConclusion\u003c/h2\u003e \u003cp\u003eLow preoperative HCO3- and high lactate levels may be preoperative risk factors for 90-day postoperative mortality in patients with non-occlusive mesenteric ischemia. However, patients on hemodialysis die from discontinuing hemodialysis even after surviving the acute postoperative phase. Hence, indications for emergency surgery in patients with risk factors for postoperative mortality should be carefully determined.\u003c/p\u003e","manuscriptTitle":"Preoperative Risk Factors for 90-day Postoperative Mortality Outcome in Patients With Non-occlusive Mesenteric Ischemia","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2024-01-05 18:14:50","doi":"10.21203/rs.3.rs-3812957/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2024-02-02T13:12:46+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2024-01-09T19:00:13+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"ee8e0f34-51ab-4515-b6a6-aeab40fd427a","date":"2024-01-08T13:14:02+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"985bb1f4-418d-4022-bba4-3d6cd32f4773","date":"2024-01-08T13:09:53+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2024-01-08T13:06:59+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2024-01-04T16:25:32+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2024-01-04T00:42:28+00:00","index":"","fulltext":""},{"type":"submitted","content":"Langenbeck's Archives of Surgery","date":"2023-12-27T15:50:38+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"langenbecks-archives-of-surgery","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"laos","sideBox":"Learn more about [Langenbeck's Archives of Surgery](http://link.springer.com/journal/423)","snPcode":"423","submissionUrl":"https://submission.nature.com/new-submission/423/3","title":"Langenbeck's Archives of Surgery","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false}}],"origin":"","ownerIdentity":"f4530222-1f76-4db1-bba0-fcce40121ecb","owner":[],"postedDate":"January 5th, 2024","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"under-review","subjectAreas":[],"tags":[],"updatedAt":"2024-06-17T03:47:15+00:00","versionOfRecord":[],"versionCreatedAt":"2024-01-05 18:14:50","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-3812957","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-3812957","identity":"rs-3812957","version":["v1"]},"buildId":"qtupq5eGEP_6zYnWcrvyt","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}