Ischemic Colitis after Cardiac Surgery: Can We Foresee the Threat?

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Predicting outcomes of mesenteric ischemia postcardiac surgery: A systematic review

OBJECTIVE

This systematic review aims to identify predictors of outcomes of mesenteric ischemia in patients following cardiac surgery.

METHODS

A comprehensive literature search was done on EMBASE, PubMed, Ovid MEDLINE, and SCOPUS using keywords relating to bowel ischemia and cardiac surgery. Database search results were screened by at least two authors and 32 articles were selected for inclusion in this review.

RESULTS

Data on 1907 patients were analyzed. The mean age was 70.0 ± 2.99 years and the prevalence of bowel ischemia was 1.74%. Advanced age was a significant risk factor. 63.16% of patients reported were men, and 58.4% of patients died in hospital. There was heterogeneity in the reported significance of the following preoperative risk factors: hypertension, smoking status, type 2 diabetes mellitus, end-stage renal disease, preoperative left ventricular ejection fraction <35%. Cardiopulmonary bypass (CPB) time, preoperative/operative intra-aortic balloon pump (IABP) support, and inotrope usage were significantly associated with the development of mesenteric ischemia; however, other intraoperative factors including the type of cardiac surgery and duration of aortic cross-clamping had varying levels of reported significance. There were discrepancies in the reported significance of leukocytosis and metabolic acidosis (pH <7.3) as postoperative markers. Postoperative vasopressor use, prolonged ventilation time, and elevation in lactate, transaminases, creatinine, and intestinal fatty acid-binding protein (IFABP) levels were found to be strongly associated with bowel ischemia.

CONCLUSION

This systematic review found the strongest associations of mesenteric ischemia postcardiac surgery to be advanced age, CPB time, rise in lactate, transaminases, creatinine, and IFABP. IABP support, vasopressor, and inotrope use as well as prolonged ventilation were strongly linked too.

Factors influencing hospital stay duration for patients with mild ischemic colitis: a retrospective study

Background

Ischemic colitis is the most prevalent ischemic injury of the gastrointestinal tract. The majority of patients with mild ischemic colitis usually achieve complete clinical recovery shortly. However, the predictors of longer hospital stay duration are unclear. This study aimed to evaluate the predictors of hospital stay duration for patients with mild ischemic colitis.

Methods

We retrospectively evaluated 100 patients with mild ischemic colitis between January 2010 and December 2020 at Xiangya Hospital (a tertiary care center). The clinical characteristics and therapeutic drugs of patients who were hospitalized for ≤ 8 days and ≥ 12 days were compared.

Results

Of the 100 patients included, 63 (63%) were hospitalized for ≤ 8 days and 37 (37%) were hospitalized for ≥ 12 days. Patients with cerebrovascular disease (29.7% vs. 11.1%, p = 0.019) and abdominal surgical history (29.7% vs. 7.9%, p = 0.004) were more likely to be hospitalized for ≥ 12 days than for ≤ 8 days. The d-dimer levels [0.78 (0.41–1.82) vs. 0.28 (0.16–0.73), p = 0.001] and positive fecal occult blood test results (86.5% vs. 60.3%, p = 0.006) were higher in patients who were hospitalized for ≥ 12 days than in those who were hospitalized for ≤ 8 days. Probiotic use was greater in patients hospitalized for ≤ 8 days (76.2% vs. 54.1%, p = 0.022). Multivariate analysis indicated that cerebrovascular disease (odds ratio [OR] = 4.585; 95% confidence interval [CI] 1.129–18.624; p = 0.033), abdominal surgical history (OR = 4.551; 95% CI 1.060–19.546; p = 0.042), higher d-dimer levels (OR = 1.928; 95% CI 1.024–3.632; p = 0.042), and higher positive fecal occult blood test results (OR = 7.211; 95% CI 1.929–26.953; p = 0.003) were associated with longer hospital stays.

Conclusion

Cerebrovascular disease, abdominal surgical history, higher d-dimer levels, and higher positive fecal occult blood test results are independent and significant factors that influence longer hospital stays for patients with mild ischemic colitis. Probiotics helped reduce hospital stay in these patients.

Chronic obstructive pulmonary disease is associated with worse outcomes in ischemic colitis: a nationwide retrospective study

BACKGROUND

Ischemic colitis (IC) occurs when the blood supply of the large intestine becomes compromised. Several cardiovascular conditions, such as coronary artery disease, congestive heart failure, and atrial fibrillation, are well-established risk factors for the development of IC. The effects of pulmonary conditions, namely chronic obstructive pulmonary disease (COPD), on IC have not been well studied.

AIMS

Our aim was to elucidate if the presence of COPD worsened outcomes in patients with IC.

METHODS

Retrospective analysis of patients hospitalized with IC in 2016 was evaluated using the National Inpatient Sample database. Baseline demographic data, length of hospital stay (LOS), total hospital cost/charge, rates of colectomy, and in-hospital mortality were extracted from the database. Categorical variables were compared using the chi-square test and continuous variables were compared using the t-test.

RESULTS

A total of 25,035 patients with IC were identified while 4482 of these patients also had COPD. We found that IC patients with COPD had a longer LOS (5.8 days vs 4.4 days; P<0.01), higher total hospital charge ($56,682 vs $42,365; P<0.01), higher total hospital cost ($13,603 vs $10,238; P<0.01), higher mortality rate (6.5% vs 3.1%; P<0.01), and higher colectomy rate (5.1% vs 3.7%; P<0.01).

CONCLUSIONS

The presence of COPD portends poor outcomes in patients with IC. This was evidenced by increased risk of death and increased risk of undergoing colectomy. Given these findings, patients with COPD warrant closer observation. We advocate that COPD be considered as part of the risk assessment of patients with acute IC who need surgical intervention.

Maintaining oxygen delivery is crucial to prevent intestinal ischemia in critical ill patients

Background

Intestinal ischemia is a common complication with obscure pathophysiology in critically ill patients. Since insufficient delivery of oxygen is discussed, we investigated the influence of oxygen delivery, hemoglobin, arterial oxygen saturation, cardiac index and the systemic vascular resistance index on the development of intestinal ischemia. Furthermore, we evaluated the predictive power of elevated lactate levels for the diagnosis of intestinal ischemia.

Methods

In a retrospective case-control study data (mean oxygen delivery, minimum oxygen delivery, systemic vascular resistance index) of critical ill patients from 02/2009–07/2017 were analyzed using a proportional hazard model. General model fit and linearity were tested by likelihood ratio tests. The components of oxygen delivery (hemoglobin, arterial oxygen saturation and cardiac index) were individually tested in models.

Results

59 out of 874 patients developed intestinal ischemia. A mean oxygen delivery less than 250ml/min/m² (LRT vs. null model: p = 0.018; LRT for non-linearity: p = 0.012) as well as a minimum oxygen delivery less than 400ml/min/m² (LRT vs null model: p = 0.016; LRT for linearity: p = 0.019) were associated with increased risk of the development of intestinal ischemia. We found no significant influence of hemoglobin, arterial oxygen saturation, cardiac index or systemic vascular resistance index. Receiver operating characteristics analysis for elevated lactate levels, pH, CO₂ and central venous saturation was poor with an area under the receiver operating characteristic of 0.5324, 0.52, 0.6017 and 0.6786.

Conclusion

There was a significant correlation for mean and minimum oxygen delivery with the incidence of intestinal ischemia for values below 250ml/min/m² respectively 400ml/min/m². Neither hemoglobin, arterial oxygen saturation, cardiac index, systemic vascular resistance index nor elevated lactate levels could be identified as individual risk factors.

Diagnostic methods and drug therapies in patients with ischemic colitis

PURPOSE

Ischemic colitis (IC) is the most prevalent ischemic injury of thegastrointestinal tract. Clinical features of IC such as acute abdominal pain, hematochezia,and diarrhea are similar to those of acute mesenteric ischemia, inflammatorybowel disease, or infectious bowel disease, and their relative ambiguity candelay diagnosis and treatment. To comprehensively detail the current state ofdiagnostic methods and available drug therapies for detecting and treating IC,this review aims to provide a concise and practical summary of thecorresponding literature.

METHODS

PubMed and Cochrane Library were searched toretrieve all published studies reporting the diagnostic methods and drugtherapies in patients with ischemic colitis. The search strategy of drugtherapy includes human and animal data.

RESULTS

Colonoscopy combined with histopathologicalbiopsy is the standard of diagnosis for the IC. Most patients respond well tothe conservative treatment, and surgical consultation is needed when conservativetreatment is ineffective. Studies of potential drug therapy have beendeveloped, including phosphodiesterase type 5 inhibitors, pentoxifylline,rebamipide, prostaglandin E1, and polydeoxyribonucleotide.

CONCLUSION

Accurate diagnoses and effective treatmentshave helped reduce the mortality rate and improve prognoses for patientsafflicted with IC, and corresponding drug therapies have been constantlyupdated as new research has emerged.

The correlation between bowel complications and cardiac surgery

Although advances in knowledge and technology have improved outcomes in surgical cardiac patients over the last decade, complications following cardiac operations still remain to be potentially fatal. Gastrointestinal complications, in particular, tend to have high rates of reintervention and mortality following cardiac surgery, with ischemia and hemorrhage being two of the commonest underlying causes. The intention of this review is to identify which risk factors play important roles in predisposing patients to such complications and to gain better insight into the pathogenesis of the sequelae. Furthermore, strategies for prevention have been discussed to educate and increase awareness of how adverse cardiac surgical outcomes can be minimized.

[Comparison of quality of life and long-term outcomes following mitral valve replacement through robotically assisted versus median sternotomy approach]

OBJECTIVE

To compare the mid- and long-term outcomes of patients receiving mitral valve replacement through robotically assisted and conventional median sternotomy approach.

METHODS

The data of 47 patients who underwent da Vinci robotic mitral valve replacement in our hospital between January, 2007 and December, 2015 were collected retrospectively (robotic group). From a total of 286 patients undergoing mitral valve replacement through the median thoracotomy approach between March, 2002 and June, 2014, 47 patients were selected as the median sternotomy group for matching with the robotic group at a 1:1 ratio. The perioperative data and follow-up data of the patients were collected, and the quality of life (QOL) of the patients at 30 days and 6 months was evaluated using the Quality of Life Short Form Survey (SF-12). The time of returning to work postoperatively and the patients' satisfaction with the surgical incision were compared between the two groups.

RESULTS

All the patients in both groups completed mitral valve replacement successfully, and no death occurred during the operation. In the robotic group, only one patient experienced postoperative complication (pleural effusion); in median sternotomy group, one patient received a secondary thoracotomy for management of bleeding resulting from excessive postoperative drainage, and one patient died of septic shock after the operation. The volume of postoperative drainage, postoperative monitoring time, ventilation time, and postoperative hospital stay were significantly smaller or shorter in the robotic group than in the thoracotomy group (P < 0.05). There was no significant difference in the incidence of postoperative complications between the two groups. Assessment of the patients at 30 days after the operation showed a better quality of life in the robotic group, but the difference between the two groups tended to diminish at 6 months. The patients in the robotic group reported significantly better satisfaction with the incision than those in the thoracotomy group (P < 0.001). At 6 months after the operation, the patients in the robotic group showed significantly faster recovery of work and daily activities than those in the thoracotomy group.

CONCLUSIONS

Robotically assisted mitral valve replacement is safe and reliable. Compared with the median sternotomy approach, the robotic approach is less invasive and promotes faster postoperative recovery of the patients, who have better satisfaction with the quality of life and wound recovery.

Predictors of mortality following emergency open colectomy for ischemic colitis: a single-center experience

Background

Ischemic colitis (IC) is a severe emergency in gastrointestinal surgery. The aim of the present study was to identify the predictors of postoperative mortality after emergent open colectomy for IC treatment. Additionally, we compared postoperative outcomes of patients undergoing emergent colectomy due to aortic surgery-related IC (AS-IC group) vs. other IC etiologies (Other-IC group).

Methods

We analyzed records of consecutive patients who underwent emergency open colectomy for IC between 2008 and 2019. Logistic regression analysis was performed to identify clinical and operative parameters associated with postoperative mortality. The AS-IC and Other-IC groups were compared for mortality, morbidity, ICU stay, hospital stay, and survival.

Results

During the study period, 94 patients (mean age, 67.4 ± 13.7 years) underwent emergent open colectomy for IC. In the majority of cases, IC involved the entire colon (53.2%) and vasopressor agents were required preoperatively (63.8%) and/or intraoperatively (78.8%). Thirty-four patients underwent surgery due to AS-IC, whereas 60 due to Other-IC causes. In the AS-IC group, 9 patients had undergone endovascular aortic repair and 25 open aortic surgery; 61.8% of patients needed aortic surgery for ruptured abdominal aortic aneurism (AAA). Overall, 66 patients (70.2%) died within 90 days from surgery. The AS-IC and Other-IC groups showed similar operative outcomes and postoperative complication rates. However, the duration of the ICU stay (19 days vs. 11 days; p = 0.003) and of the total hospital stay (22 days vs. 16 days; p = 0.016) was significantly longer for the AS-IC group than for the Other-IC group. The rate of intestinal continuity restoration at 1 year after surgery was higher for the Other-IC group than for the AS-IC group (58.8% vs. 22.2%; p = 0.05). In the multivariate model, preoperative increased lactate levels, a delay between signs/symptoms’ onset and surgery > 12 h, and the occurrence of postoperative acute kidney injury were statistically associated with postoperative mortality. Neither IC etiology (aortic surgery vs. other etiology) nor ruptured AAA was associated with postoperative mortality.

Conclusion

Emergency open colectomy for IC is associated with high postoperative mortality, which appears to be unrelated to the IC etiology. Preoperative lactate levels, > 12-h delay to surgery, and postoperative acute kidney injury are independent predictors of postoperative mortality.

Review article: the pharmacological causes of colon ischaemia

BACKGROUND

Colon ischaemia is the most common ischaemic disorder of the gastrointestinal system, can affect any segment of the colon, and may present with a range of symptoms. Diagnosis can be challenging due to symptom overlap with other conditions, varied aetiology, and often rapid and self-resolving course.

AIM

To review comprehensively the literature regarding the pharmacological aetiologies of colonic ischaemia to enhance the understanding of the various mechanisms of disease, presentations, distribution, and outcomes.

METHODS

A PubMed search for "colon ischaemia" and "ischaemic colitis" alone as well as in combination with various known pharmacologic causes was performed. Only the highest quality and relevant literature was included in this review. The quality of the literature for each association was rated by the authors and a consensus was made when discrepancies were encountered. Only associations that were deemed "moderate" or "strong" were included.

RESULTS

The literature considering pharmacologically associated colonic ischaemia is diverse, lacks codification and is characterised by numerous case reports and case series. Constipation-inducing drugs, digoxin, hormonal therapies, illicit drugs, immunomodulators, laxatives, and NSAIDs were strongly associated with colonic ischaemia. Antimicrobials, appetite suppressants, chemotherapies, decongestants, diuretics, ergot alkaloids, serotonin agents, statins, and vasopressor agents were moderately associated.

CONCLUSIONS

Patients presenting with abdominal pain, diarrhoea, or bloody stool need to be evaluated for the possibility of this condition and treated accordingly. Timely diagnosis is necessary to improve patient outcomes. This review aims to increase awareness among clinicians regarding the presentation of pharmacologically induced colonic ischaemia.

Advents in the Diagnosis and Management of Ischemic Colitis

BACKGROUND

Ischemic colitis (IC) is a common type of ischemic insult, resulting from decreased arterial blood flow to the colon. This disease can be caused from either atherosclerotic occlusive vascular disease or non-occlusive disease. The aim of this study is to present the diagnostic methodology and management of this severe disease based on current literature.

METHODS

A literature search has been done including articles referring to modern diagnosis and management of IC.

RESULTS

IC is usually a transient disease, but it can also cause gangrene of the colon, requiring emergency surgical exploration. Diagnosis is troublesome and is based on imaging examinations, mainly computerized tomography, which in association with colonoscopy can delineate the distribution pattern and severity of disease.

CONCLUSION

The majority of patients with mild disease have usually complete clinical recovery within a short period. The severe forms of the disease carry high morbidity and mortality rates and prompt surgical intervention is the only way to improve the associated severe prognosis.