Gastrointestinal complications after coronary artery bypass grafting: a national study of morbidity and mortality predictors

Feasibility and Safety of Concomitant Laparoscopic Cholecystectomy With Open-Heart Surgery: A Systematic Review and Our Early Clinical Experience

Significant valvular or coronary artery disease may co-exist in patients presenting with symptomatic cholelithiasis. Isolated laparoscopic cholecystectomy in these cases is often associated with cardiac complications. Addressing the cardiac condition first may result in flaring up of cholecystitis during postoperative recovery and is associated with adverse outcomes. Open-heart surgery followed by laparoscopic cholecystectomy during a single operative setting is an option in these situations. The aim of our study is to review the published articles for this strategy and to share our initial experience with two such patients. PubMed, OVID Medline, and Cochrane library database were used, and we searched these databases using Medical Subject Headings (MeSH) terms and keywords from the inception date until August 1, 2023, and did not restrict our search to any language, study type, sample size, or publication date. All the publications reporting concomitant laparoscopic cholecystectomy and open-heart surgery were identified and a systematic review was carried out. Our first case underwent coronary artery bypass grafting and laparoscopic cholecystectomy. The second patient underwent a double valve replacement and laparoscopic cholecystectomy. Both the patients made an uneventful recovery, and are alive and doing well. Concomitant open-heart surgery and laparoscopic cholecystectomy in certain situations may be necessary and can be performed safely.

Giant Pancreatic Pseudocyst after Coronary Artery Bypass Graft in a Hemodialysis Patient: A Case Report

End-stage renal disease (ESRD) patients have a high prevalence of coronary artery disease, and coronary artery bypass graft (CABG) is one of the essential treatments. ESRD patients undergoing CABG surgery have an increased risk of postoperative complications, including acute pancreatitis. Here, we present the unique case of an exceptionally large pancreatic pseudocyst caused by pancreatitis in an ESRD patient after CABG surgery. A 45-year-old male with ESRD under maintenance hemodialysis received CABG surgery for significant coronary artery disease. Two weeks later, he experienced worsening abdominal pain and a palpable mass was noticed in the epigastric region. Computer tomography revealed an unusually large pseudocyst measuring 21 × 17 cm in the retroperitoneum due to necrotizing pancreatitis. The patient underwent percutaneous cystic drainage, and the symptoms were significantly improved without surgical intervention. Factors such as prolonged cardiopulmonary bypass time, postoperative hypotension, and intradialytic hypotension appeared to have contributed to the development of severe pancreatitis in this case. This report highlights the rarity of a giant pancreatic pseudocyst in an ESRD patient after CABG surgery and emphasizes the importance of vigilant postoperative care.

A National Evaluation of Emergency General Surgery Outcomes Among Hospitalized Cardiac Patients

INTRODUCTION

Emergency general surgery among cardiac surgery patients is increasingly common and consequential. We sought to characterize the true burden of emergency general surgery among hospitalized complex cardiac patients.

METHODS

We performed a retrospective analysis of the 2016-2017 National Inpatient Sample. We included adult patients with a primary diagnosis of complex cardiac disease. We then compared patients who underwent emergency general surgery (GS-OR) with those who did not (non-GS-OR). The primary outcome was mortality; secondary outcomes included length of stay and hospitalization costs.

RESULTS

We identified 10.2 million patients with a primary diagnosis of complex cardiac disease, of which 148,309 (1.4%) underwent GS-OR. Mortality rates were significantly higher in the GS-OR group (11.0% versus 5.0%, P < 0.001). Among all cardiac patients, GS-OR was associated with 2.2 times increased odds of death (aOR: 2.2, P < 0.001). GS-OR patients also had longer length of stays (14.1 versus 5.8 d, P < 0.001). Among all cardiac patients, GS-OR was associated with an 8.1-day longer length of stay (P < 0.001). GS-OR patients were less often routinely discharged home (31.7% versus 45.3%, P < 0.001) and incurred higher inpatient costs ($46,136 versus $16,303, P < 0.001). Among all cardiac patients, GS-OR patients incurred $30,102 higher hospitalization costs (P < 0.001).

CONCLUSIONS

Emergency general surgery among cardiac surgery patients is associated with a greater than two-fold increase in mortality, longer length of stays, higher rates of nonroutine discharge, and higher hospitalization costs. Emergency general surgery complications account for 4.0% of total inpatient costs of cardiac surgery patients and merit further study.

Short-Term Outcomes and Risk Factors of In-Hospital Mortality in Patients Suffering Acute Mesenteric Ischemia after Cardiac Surgery: Role of Opioids and Lactic Acid

Acute mesenteric ischemia (AMI) is associated with poor clinical results after cardiac surgery. The aim of this study was to analyse the influence of AMI on short-term outcomes and all relevant risk factors of in-hospital mortality after cardiac surgery. Moreover, we aimed to investigate the role of opioids and lactic acid in the detection and prevention of AMI. Between August 2011 and September 2015, 176 consecutive patients with gastrointestinal complications after undergoing open-heart surgery were identified and included in this study. All patients were divided into two groups: AMI group (n = 39) and non-AMI group (n = 137). In terms of comorbidities, the groups were fairly equal and showed no significant differences. Dialysis was significantly higher (p < 0.001) in patients that suffered from AMI. Moreover, gastro-intestinal symptoms such as muscular defense (p = 0.004) and the laparotomy rate (p < 0.001) were significantly higher in the AMI group. Likewise, in-hospital mortality (p < 0.001) was significantly higher in patients with detected AMI. Univariate (p < 0.001) and multivariate analysis (p = 0.025) of both groups revealed that lactic acid value >2 mmol/L and present treatment with opioids are independent combined predictors of mesenteric ischemia in patients after undergoing cardiac surgery. Moreover, multivariate analysis showed peripheral vascular disease (p = 0.004), dialysis (p = 0.010), and septic shock (p = 0.003) as relevant predictors of in-hospital mortality. Prolonged analgetic treatment with opioids and sudden increase of lactic acid levels are independent combined predictors of mesenteric ischemia in patients after undergoing cardiac surgery. Furthermore, peripheral vascular disease, dialysis, and septic shock are relevant predictors for in-hospital mortality.

Organ damage evaluation in a temperature-controlled circulatory arrest rat model

BACKGROUND

Deep hypothermic circulatory arrest (DHCA) is commonly used in adult aortic surgery and pediatric complex congenital heart disease, and is associated with pathophysiological changes and postoperative complications. Here, a temperature-controlled circulatory arrest model in rats was established to study the suitable temperature of circulatory arrest by investigating the damage to body organs under different temperatures.

METHODS

Thirty Sprague‒Dawley rats were randomly divided into 5 equal groups for DHCA experiments: I (15-20 °C), II (20-25 °C), III (25-30 °C), IV (normothermic cardiopulmonary bypass), and V (sham operation group). Blood gas analysis, homodynamic parameters, and intervals of cardiac recovery were measured at different time points in all groups. Morphological changes in intestinal tissue were observed under light and electron microscopes. Oxidative stress was measured by MPO activity, MDA, and SOD content. Tissue damage was confirmed by serum detection of ALT, AST, BUN, Cr, and LDH. To examine the inflammatory response, cytokines, including IL-1, IL-4, IL-10, IFN-γ, and TNF-α, were detected.

RESULTS

The extracorporeal circulation technique caused damage to the body; the degree of the damage caused by the circulatory arrest technique may be related to circulating temperature, with the least amount of damage occurring at 20-25 °C compared to 15-20 °C and 25-30 °C. Ischemia and hypoxia can cause intestinal tissue damage, which manifests primarily as a loss of the intestinal mucosal barrier. Ischemic intestinal damage caused by DHCA was not associated with inflammation.

CONCLUSION

The study provides new insights into the pathophysiologic mechanisms of DHCA.

Risk factors for ischemic gastrointestinal complications in patients undergoing open cardiac surgical procedures: A single-center retrospective experience

BACKGROUND

Ischemic gastrointestinal complications (IGIC) following cardiac surgery are associated with high morbidity and mortality and remain difficult to predict. We evaluated perioperative risk factors for IGIC in patients undergoing open cardiac surgery.

METHODS

All patients that underwent an open cardiac surgical procedure at a tertiary academic center between 2011 and 2017 were included. The primary outcome was IGIC, defined as acute mesenteric ischemia necessitating a surgical intervention or postoperative gastrointestinal bleeding that was proven to be of ischemic etiology and necessitated blood product transfusion. A backward stepwise regression model was constructed to identify perioperative predictors of IGIC.

RESULTS

Of 6862 patients who underwent cardiac surgery during the study period, 52(0.8%) developed IGIC. The highest incidence of IGIC (1.9%) was noted in patients undergoing concomitant coronary artery, valvular, and aortic procedures. The multivariable regression identified hypertension (odds ratio [OR] = 5.74), preoperative renal failure requiring dialysis (OR = 3.62), immunocompromised status (OR = 2.64), chronic lung disease (OR = 2.61), and history of heart failure (OR = 2.03) as independent predictors for postoperative IGIC. Pre- or intraoperative utilization of intra-aortic balloon pump or catheter-based assist devices (OR = 4.54), intraoperative transfusion requirement of >4 RBC units(OR = 2.47), and cardiopulmonary bypass > 180 min (OR = 2.28) were also identified as independent predictors for the development of IGIC.

CONCLUSIONS

We identified preoperative and intraoperative risk factors that independently increase the risk of developing postoperative IGIC after cardiac surgery. A high index of suspicion must be maintained and any deviation from the expected recovery course in patients with the above-identified risk factors should trigger an immediate evaluation with the involvement of the acute care surgical team.

Developing and verifying a multivariate model to predict the survival probability after coronary artery bypass grafting in patients with coronary atherosclerosis based on the MIMIC-III database

BACKGROUND

Coronary atherosclerosis is one of the main cardiovascular diseases affecting the global population. Coronary artery bypass grafting (CABG) is commonly used to improve the survival probability of patients with coronary atherosclerosis. However, the prognosis of patients after CABG remains unclear.

OBJECTIVES

We aimed to construct a novel nomogram comprising readily available indicators to predict the 1-, 2-, and 3-year survival rates after CABG in patients with coronary atherosclerosis.

METHODS

We utilized the Medical Information Mart for Intensive Care III (MIMIC-III) database for the study. The calibration plot, concordance index (C-index), net reclassification index (NRI), integrated discrimination improvement (IDI), and area under the receiver operating characteristic curve (AUROC) were used to evaluate the performance of the model, and to compare the nomogram with the Sequential Organ Failure Assessment (SOFA) score and Simplified Acute Physiology Score II (SAPS II) in order to illustrate the clinical effectiveness of the model.

RESULTS

The multivariate Cox regression model showed that age, marital status, body mass index, creatinine, platelet count, red cell distribution width, heart rate, intensive-care unit stay time, and Elixhauser Comorbidity Index were risk factors. The C-indexes of the nomogram exceeded 0.75, and its NRI and IDI were both higher than 0. The AUROCs were larger for the nomogram than for the SAPS II and SOFA score.

CONCLUSION

Our new nomogram is a personalized tool that helps clinicians choose treatment options and predict the long-term prognosis of patients.

Prophylactic use of proton pump inhibitors post-cardiac surgery

AIMS/BACKGROUND

Gastrointestinal bleeding significantly increases morbidity and mortality rates postoperatively in patients undergoing cardiac surgery. The prophylactic prescribing of proton pump inhibitors post-cardiac surgery is currently a class IIa recommendation of the European Association of Cardio-Thoracic Surgery.

METHOD

A retrospective review of patients who underwent cardiac surgery between July and December 2019 in the authors' hospital was carried out, using discharge summaries. New treatment charts were introduced with a pre-printed proton pump inhibitor included in the 'regular medication' section of the treatment chart and two reaudits were performed using the same methodology.

RESULTS

Before the intervention, 47% were prescribed omeprazole postoperatively, compared to 74% (P<0.001) and 66% (P=0.008) in the first and second reaudits respectively. Gastrointestinal bleeding was more common pre-intervention (4% vs 1% respectively; P=0.10).

CONCLUSIONS

This intervention resulted in a statistically significant improvement in the prescription of postoperative omeprazole and a decrease in gastrointestinal bleeds. However, other risk factors such as diabetes mellitus, arteriosclerosis and procedure urgency may have contributed to the absence of statistical significance in the latter.

Risk Factors Associated with In-Hospital Mortality for Patients with Acute Abdomen After Cardiac Surgery

OBJECTIVES

Management of acute abdomen (AA) differs due to the heterogeneity of underlying pathophysiology. Complications of AA and its overall outcome after cardiac surgery are known to be associated with poor results. The aim of this retrospective analysis was to evaluate risk factors for AA in patients undergoing cardiac surgery.

METHODS

Between December 2011 and December 2014, a total of 131 patients with AA after cardiac surgery were identified and retrospectively analyzed using our institutional database. Statistical analysis of risk factors concerning in-hospital mortality of mentioned patient cohort was performed using IBM SPSS Statistics.

RESULTS

Overall in-hospital mortality was 54.2% (71/131). Analyzing in-hospital non-survivors (NS) versus in-hospital survivors (S) peripheral artery disease (28.2% vs. 11.7%; p = 0.03), the need for assist device therapy (33.8% vs. 16.7%; p = 0.03) and the requirement of hemodialysis (67.6% vs. 23.3%; p < 0.01) were significantly higher in NS. Furthermore, lactic acid values at onset of symptoms were shown to be significantly higher in NS (5.7 ± 5.7 mmol/L vs. 2.8 ± 2.9 mmol/L; p < 0.01). Assured diagnosis of mesenterial ischemia was strongly associated with worse outcome (odds ratio 10.800, 95% confidence interval 2.003-58.224; p = 0.006).

CONCLUSION

In conclusion, in critically ill patients after performed cardiac surgery peripheral vascular disease, need for supportive hemodynamic assist device systems and occurrence of renal failure are risk factors associated with worsen outcome. Additionally, rise of lactic acid could potentially be associated with onset of intestinal malperfusion and should be taken into account in therapeutic decisions preventing fatal mesenterial ischemia.

Retrograde Extrusion of Coronary Thrombus During Urgent Aortocoronary Bypass Surgery: A Case Report

A 73-year-old man underwent urgent coronary artery bypass grafting after an acute myocardial infarction. An angiogram had revealed multivessel disease with a circumflex artery lesion suspected as the primary culprit. On separation from cardiopulmonary bypass, transesophageal echocardiography revealed a new mobile mass in the aortic root. Cardiopulmonary bypass was reinstituted and a large thrombus emanating from the left coronary ostium was surgically removed. We hypothesize that the thrombus had originated from coronary retrograde extrusion during venous grafting. This case illustrates an unusual source of emboli during coronary artery bypass grafting and emphasizes the importance of perioperative transesophageal echocardiography for the prevention of potentially catastrophic outcomes.

Gastrointestinal Complications After Cardiac Surgery: A Nationwide Population-Based Analysis of Morbidity and Mortality Predictors

OBJECTIVE

The authors aimed to evaluate the incidence, risk factors, and outcomes of gastrointestinal (GI) complications in cardiac and aortic surgery using recent versions of the National (Nationwide) Inpatient Sample (NIS) to provide clinicians with a better understanding of these uncommon but potentially serious complications.

DESIGN

Population-based study.

SETTING

NIS database 2010-2012.

PARTICIPANTS

Patients undergoing cardiac and aortic aneurysm repair surgeries.

INTERVENTIONS

Not applicable.

MEASUREMENTS AND MAIN RESULTS

The most common GI complication was postoperative ileus, which also had the lowest mortality, followed by GI hemorrhage. Mesenteric ischemia demonstrated the highest mortality, followed by intestinal perforation. Mortality was highest in those with infective endocarditis (16.02%), followed by myocardial infarction (12.48%). GI complications were highest in patients undergoing repair of abdominal aortic aneurysm, followed by off-pump coronary artery bypass grafting.

CONCLUSION

In conclusion, this study demonstrated that GI complications after cardiac surgery occurred at a rate of 4.17%, which is similar to that reported in the NIS database from 1998 to 2002 in coronary artery bypass grafting patients, but higher than that previously described in single-center studies. GI complications after cardiac surgery increased inpatient mortality 3-fold and more than doubled length of stay. Improved recognition and understanding of the predisposing risk factors and complications elucidated in this study could serve to increase the necessity for timely diagnosis and treatment of patients at high risk for GI complications after cardiac surgery.

Synchronous Open Heart Surgery and Laparoscopic Cholecystectomy: An Observational Case Study with 28 Patients

Acute cholecystitis (AC) may be a severe problem and may increase the mortality rate and hospital stay in patients who undergo open heart surgery (OHS), due to its aggressive course; therefore, AC should be treated as soon as possible. We aimed to present data on our synchronous cardiac and laparoscopic cholecystectomy (LC) operations performed for AC complicating patients with cardiac disease and who were waiting to undergo OHS. Between January 2008 and September 2014, we performed 2773 OHSs in Medical Park Gaziantep Hospital. Among these, 28 (1%) patients underwent concomitant LC in the same session by the same experienced surgeon. The mean age of the patients was 61.4 ± 9.1 years, and the proportion of males was 71.4 per cent. Acalculous cholecystitis was found in 42.9 per cent of the patients. Patients stayed in the intensive care unit for 3.1 ± 1.4 days and were discharged from the hospital after 16.5 ± 6.3 days. Postoperative 2-year follow-up was completed in all patients with a mean follow-up period of 3.4 ± 2.0 years. The overall complication rate was 28.6 per cent. LC-related complications were seen in four patients. No inhospital mortality was observed. Only one patient who underwent mitral valve replacement and tricuspid valve repair died in the second year after the operation due to congestive heart failure. Three patients died due to noncardiac reasons in the follow-up period. By increasing the experiences of surgeons in laparoscopic surgery in critically ill patients, LC can be safely performed concurrently in patients scheduled for OHS.

Changing trends in abdominal surgical complications following cardiac surgery in an era of advanced procedures. A retrospective cohort study

BACKGROUND

Abdominal complications following cardiopulmonary bypass (CPB) procedures may have mortality rates as high as 25%. Advanced procedures such as ventricular assist devices, artificial hearts and cardiac transplantation are being increasingly employed, changing the complexity of interventions. This study was undertaken to examine the changing trends in complications and the impact of cardiac surgery on emergency general surgery (EGS) coverage.

METHODS

A retrospective review was conducted of all CPB procedures admitted to our ICU between Jan. 2007 and Mar. 2010. The procedures included coronary bypass (CABG), valve, combination (including adult congenital) and advanced heart failure (AHF) procedures. The records were reviewed to obtain demographics, need for EGS consult/procedure and outcomes.

RESULTS

Mean age of the patients was 66 ± 8.5 years, 71% were male. There were 945 CPB procedures performed on 914 patients during this study period. Over 39 months, 23 EGS consults were obtained, resulting in 10 operations and one hospital death (10% operative mortality). CABG and valve procedures had minimal impact on EGS workload while complex cardiac and AHF procedures accounted for significantly more EGS consultations (p < 0.005) and operations (p < 0.005). The majority of consultations were for small bowel obstruction/ileus (n = 4, 17%), cholecystitis (n = 3, 13%) and to rule out ischemia (n = 2, 9%)

CONCLUSIONS

In the era of modern critical care and cardiac surgery, advanced technology has increased the volume of complex CPB procedures increasing the EGS workload. Emergency general surgeons working in institutions that perform advanced procedures should be aware of the potential for general surgical complications perioperatively and the resultant nuances that are associated with operative management in this patient population.

Elevated endothelin-1 level is a risk factor for nonocclusive mesenteric ischemia

OBJECTIVE

Nonocclusive mesenteric ischemia may occur after cardiac surgery, commonly in conjunction with the use of cardiopulmonary bypass. Some evidence suggests that endothelin-1 serum levels are increased in patients with mesenteric ischemia, but the association of endothelin-1 and nonocclusive mesenteric ischemia has not been studied. The objective was to investigate whether elevated levels of endothelin-1 could be found in patients exhibiting nonocclusive mesenteric ischemia.

METHODS

In an observational cohort study, nonocclusive mesenteric ischemia developed in 78 of 865 patients undergoing elective cardiac surgery. Control patients were identified from the cohort through 1:1 propensity score matching. Preoperative and postoperative endothelin-1 serum levels were determined by means of enzyme-linked immunosorbent assay. Odds ratios (with 95% confidence interval) were calculated by logistic regression analyses to determine the risk of endothelin-1 for the development of nonocclusive mesenteric ischemia.

RESULTS

Patients with nonocclusive mesenteric ischemia had higher preoperative (11.3 vs 9.3 pg/mL; P = .001) and postoperative (15.7 vs 11.1 pg/mL, P < .001) levels of endothelin-1 than the controls. The probability of developing nonocclusive mesenteric ischemia increased with each picogram/milliliter endothelin-1 level preoperatively (odds ratio, 1.29; 95% confidence interval, 1.12-1.49) and each picogram/milliliter postoperatively (odds ratio, 2.04; 95% confidence interval, 1.54-2.72). Receiver operating characteristic analyses showed that elevated endothelin-1 serum levels had a high accuracy to predict nonocclusive mesenteric ischemia (optimal cutoff value of 14.5 pg/mL, area under the curve of 0.77, sensitivity 51%, and specificity 94%).

CONCLUSIONS

Endothelin-1 seems to predispose patients undergoing cardiac surgery to develop nonocclusive mesenteric ischemia. In addition, it may be a useful marker to identify patients at risk for nonocclusive mesenteric ischemia after cardiac surgery.

Vasopressin Aggravates Cardiopulmonary Bypass-Induced Gastric Mucosal Ischemia

Background/Aim: Upper gastrointestinal bleeding (UGIB) is one of the most frequent gastrointestinal complications after cardiac surgery with cardiopulmonary bypass (CPB). Endothelin expression and microcirculatory dysfunction have been shown to be involved in UGIB. The aim of this study was to analyze the effect of vasopressin during CPB on the gastric mucosal microcirculation and the involvement of the endothelin system. Methods: Eighteen pigs were randomized into three groups (n = 6 each): group I = sham, group II = CPB (1-hour CPB) and group III = CPB + vasopressin (1-hour CPB and vasopressin administration during CPB to maintain baseline arterial pressure). All animals were observed for a further 90 min after termination of CPB. Systemic hemodynamics as well as blood flow and oxygen saturation of the gastric mucosa were measured continuously. At the end of the experiment, the gastric mucosal expressions of endothelin-1 (ET-1) and its receptor subtypes A (ETA) and B (ETB) were determined by polymerase chain reaction. Gastric mucosal injury, apoptotic cell death and leukocytic infiltration were determined by histology and immunohistochemical analyses of cleaved caspase-3 and myeloperoxidase. Results: CPB decreased gastric microvascular perfusion, which was associated with an increased expression of ET-1 and ETA. Vasopressin aggravated the CPB-associated malperfusion, whereas it completely abrogated the upregulation of ET-1 and ETA. Interestingly, vasopressin did not induce gastric mucosal morphologic injury, leukocytic infiltration or apoptotic cell death. Conclusion: Vasopressin aggravates CPB-associated microvascular malperfusion of the gastric mucosa but does not induce gastric mucosal injury.

Gastrointestinal complications following cardiac surgery with cardiopulmonary bypass

Gastrointestinal complications following cardiac surgery with cardiopulmonary bypass include paralytic ileus, stress ulcer, acute ischemic colitis, gastrointestinal bleeding, acute cholecystitis, acute pancreatitis, acute hepatic failure and so on. Due to the lack of diagnostic tests with high specificity and sensitivity, the early diagnosis of these complications is difficult, which leads to a higher mortality rate. Therefore, accurately identifying the risk factors is important for early diagnosis and treatment. The purpose of this paper is to review the pathogenesis, risk factors, diagnosis and treatment of gastrointestinal complications after cardiac surgery with cardiopulmonary bypass.

Off-pump coronary artery bypass prevents visceral organ damage

OBJECTIVES

Visceral malperfusion after coronary artery bypass grafting (CABG) results in high morbidity and mortality. This study was designed to evaluate the effect of CABG performed by surgical techniques on visceral perfusion and function.

METHODS

Pigs (n = 28) were studied in four groups: I. Sham; II. Off-pump coronary artery bypass grafting (OPCAB): 1 h stabilizer with 40 min intracoronary shunt; III. Extracorporeal circulation (ECC): 1 h ECC with 40 min aortic cross-clamping and cardioplegic arrest; IV. Impella: 1 h left ventricular blood-pump support and stabilizer with 40 min intracoronary shunt. A left internal mammary to left anterior descending coronary artery bypass was performed in Groups II-IV. All animals were observed for a further 240 min. During the experiment haemodynamics, creatinine clearance, intestinal fatty acid binding protein (iFABP), pancreatic (lipase and amylase) and liver enzymes (α-glutathione s-transferase, glutamate-oxaloacetate transaminase (GOT), gamma-glutamyl transferase (GGT), glutamate dehydrogenase and glutamate-pyruvate transaminase (GPT)) were measured. Visceral perfusion (VP) was assessed in both kidneys, intestine, pancreas, liver and spleen with 15 µm fluorescent microspheres.

RESULTS

During OPCAB surgery, VP decreased slightly. Renal functional parameters, iFABP, pancreatic and liver enzymes remained unchanged. ECC and Impella led to significantly reduced renal, pancreatic and intestinal blood flow (P < 0.05). Creatinine clearance, pancreatic and liver (GPT, GGT) enzymes were significantly decreased only after ECC (P < 0.05). ECC and Impella resulted in a significantly increased iFABP level (P < 0.05). GOT was elevated significantly after surgery in Groups II, III and IV (P < 0.05).

CONCLUSIONS

CABG with ECC or Impella leads to impaired visceral blood flow and function. OPCAB minimizes these procedure associated alterations.

Is prophylactic intravenous administration of a proton pump inhibitor necessary for perioperative management of cardiac surgery?

BACKGROUND

Mortality from gastrointestinal (GI) hemorrhage caused by antiplatelet or anticoagulant therapy (or both) is quite high after cardiac surgery. We previously reported that proton pump inhibitor (PPI) therapy is indispensable in preventing postoperative GI complications. PPIs are usually administered intravenously immediately after surgery and subsequently by oral formulations. We conducted a prospective study to evaluate whether intravenous PPI followed by oral administration is more efficient as prophylaxis than oral-only administration.

METHODS AND RESULTS

We enrolled 40 patients scheduled to undergo coronary artery bypass grafting with cardiopulmonary bypass and randomly assigned them to receive oral PPIs alone (group 1) or intravenous PPI followed by oral administration (group 2). Postoperative upper GI endoscopy evaluations showed no evidence of GI bleeding. Only gastritis, esophagitis, and hiatal hernia were observed at similar incidences in the groups. Mean hospital stays were also similar, but the cost of PPI treatment was significantly lower in group 1.

CONCLUSION

No additional benefits of intravenous PPIs over oral formulations were demonstrated. Oral PPIs alone were effective and economical as prophylaxis against GI complications. Intravenous PPIs might be unnecessary in selected patients after cardiac surgery.

Prediction and prevention of upper gastrointestinal bleeding after cardiac surgery: a case control study

BACKGROUND

Gastrointestinal (GI) complications of cardiovascular surgery, particularly bleeding, occur frequently.

OBJECTIVE

To determine factors that predict upper GI bleeding (UGIB) after cardiac surgery to improve prognostication and, thus, outcomes.

METHODS

The present case-control study reviewed institutional records spanning 2002 to 2005 for consecutive patients who developed in-hospital UGIB following cardiovascular surgery. Each case was matched to two to three controls for age, sex and date of hospital admission. Demographics, pharmacotherapy (including use of in-hospital acid suppression), endoscopic findings and outcomes were recorded. After adjustment for possible confounders, including Parsonnet score and demographic parameters, conditional logistic regression analysis identified independent significant predictors of the subsequent development of UGIB.

RESULTS

The study population consisted of 131 cases (mean [± SD] age 68.8±10.2 years, 69.5% male, mean Parsonnet score 24.6±14.2) and 387 matched controls (mean age 68.8±10.8 years, 70.0% male, mean Parsonnet score 20.9±14.2). UGIB events occurred a mean of 10.3±7.7 days after cardiac surgery. Duration of mechanical ventilation (OR 3.01 [95% CI 1.44 to 6.28]), elevation of international normalized ratio (OR 1.91 [95% CI 1.31 to 2.78]) and occurrence of Clostridium difficile colitis before bleeding (OR 3.15 [95% CI 1.19 to 8.36]) were independent risk factors. Use of histamine type 2 receptor antagonists (H2RAs) (OR 0.65 [95% CI 0.38 to 1.12]) or proton pump inhibitors (PPIs) (OR 0.60 [95% CI 0.27 to 1.32]) demonstrated trends toward protecting against UGIB after cardiac surgery.

CONCLUSIONS

GI bleeding events occurred approximately 10 days after cardiac surgery in patients with a complicated postoperative course. Significant predictors of subsequent bleeding included increased duration of mechanical ventilation and elevation of international normalized ratio; routine acid suppression with PPIs should be considered in such patients. C difficile colitis also significantly predicted UGIB, and H2RAs should be considered for acid suppression. Neither H2RAs nor PPIs were effective in preventing UGIB, although the small number of patients limits definitive conclusions regarding the role of acid suppression.

Prevention and treatment of gastrointestinal complications following cardiac surgery with cardiopulmonary bypass

Acute gastrointestinal complications (GICs) following cardiac surgery with cardiopulmonary bypass (CPB) are rare but carry a high mortality rate. During CPB procedures, many factors cause a reduction of blood supply to the digestive system, tissue injury, and the release of many inflammatory mediators, which can lead to GICs such as gastrointestinal bleeding, peptic ulcers, ischemic enteritis, pancreatitis, cholecystitis, and liver failure. Close observation of clinical manifestations and early diagnosis will help timely manage these complications and improve prognosis. The purpose of this paper is to review the mechanism, risk factors, diagnosis and treatment of GICs after cardiac surgery with cardiopulmonary bypass..

Predictors of survival after gastrointestinal complications in bypass grafting

Between April 2001 and December 2005, data were collected prospectively from 2,320 consecutive patients who underwent first-time coronary artery bypass. Logistic multiple regression analyses were carried out to determine the independent predictors of gastrointestinal complications and death. There were 65 major gastrointestinal complications identified in 65 (2.8%) patients: paralytic ileus in 15, mesenteric ischemia in 12, upper gastrointestinal hemorrhage in 16, lower gastrointestinal hemorrhage in 8, small bowel obstruction in 5, pseudoobstruction in 5, and others in 4. The 30-day mortality was 21.5% (14 patients). Female sex, preoperative creatinine >200 μmol·L(-1), previous gastrointestinal pathology, low cardiac output, readmission to the intensive care unit, postoperative pulmonary complications, arrhythmias, hemofiltration, and reoperation were independent predictors of major gastrointestinal complications. Independent risk factors for death were readmission to the intensive care unit, the need for hemofiltration, reoperation, and ischemic bowel. Careful hemodynamic control and optimization of perioperative organ perfusion are important to minimize the mortality associated with major gastrointestinal complications after coronary artery bypass.

Risk factors for gastrointestinal complications in patients undergoing coronary artery bypass graft surgery

OBJECTIVE

To determine the risk factors for the development of gastrointestinal complications (GICs) after coronary artery bypass graft (CABG) surgery.

DESIGN

A single-center, retrospective study.

SETTING

A tertiary care hospital.

PARTICIPANTS

Six thousand seven hundred ninety-four patients undergoing isolated CABG surgery between 2002 and 2006.

INTERVENTIONS

Clinical characteristics of the patients with GICs and control group patients were analyzed by stepwise logistic regression analysis. The control group consisted of a total of 95 patients randomly selected among the ones who had no gastrointestinal finding or symptoms (cohort: control, 1:5 ratio).

MEASUREMENTS AND MAIN RESULTS

Nineteen patients (0.3%) developed major surgical GICs after CABG surgery. Overall, the 30-day mortality was 42.1% among patients with GICs and 2.6% without GICs. Multivariate analysis identified 4 independent predictors for GICs: age greater than 70 years (p = 0.001; odds ratio [OR] = 5.6; 95% confidence interval [CI], 2.1-25.9), reoperation for bleeding (p = 0.005; OR = 7.7; 95% CI, 2.8-56.2), a prolonged cardiopulmonary bypass time (p = 0.007; OR = 3.7; 95% CI, 1.3-15.6), and an increased postoperative creatinine level (p = 0.036; OR = 2.3; 95% CI, 1.1-13.4).

CONCLUSION

A delayed diagnosis of complications is an important problem in the management of major surgical GICs. The present results suggest that surgeons and intensivists must be alert to patients older than 70 years, a cardiopulmonary bypass time longer than 60 minutes, reoperation for bleeding after CABG surgery, and postoperative creatinine level higher than 1.7 mg/dL.

The effect of postoperative gastrointestinal complications in patients undergoing coronary artery bypass surgery

BACKGROUND

Gastrointestinal (GI) complications after coronary artery bypass graft surgery (CABG) are uncommon but associated with a disproportionate share of mortality. We thus identified variables associated with GI complications and analyzed their effect on postoperative mortality in patients undergoing isolated CABG.

METHODS

Information from patients who underwent isolated CABG at our institution during a 12-year period was obtained from the Anesthesiology Institute patient registry. Patients who experienced one or more postoperative GI complication(s) during their initial intensive care unit stay were identified. Multivariable logistic regression with backward variable selection was used to determine variables associated with GI complications and to evaluate their effect on mortality.

RESULTS

Among 16,043 patients who underwent isolated CABG, 213 (1.43%) had one or more GI complication(s). The main patient variables associated with postoperative GI complications included preoperative (odds ratio, 2.43; 95% confidence interval [CI], 1.39 to 4.23; p < 0.001) and intraoperative (odds ratio, 5.07; 95% CI, 3.08 to 8.35; p < 0.001) intraaortic balloon pump insertion, patient age (odds ratio, 1.65; 95% CI, 1.41 to 1.94; p < 0.001), intraoperative fresh-frozen plasma transfusion (odds ratio, 3.38; 95% CI, 2.12 to 5.41; p < 0.001), and cardiogenic shock (odds ratio, 3.04; 95% CI, 1.12 to 8.24). No difference was detected in complication rates between off-pump and on-pump CABG procedures (1.50% versus 1.30%, respectively; p = 0.63). Postoperative GI complication(s) after CABG was associated with a 12.98 times increase in mortality (p < 0.001).

CONCLUSIONS

This single-center cohort study indicates that GI complications after isolated CABG remain rare with an incidence 1.43%. However, GI complications portend a significant mortality. The implications of intraoperative administration of fresh-frozen plasma and insertion of an intraaortic balloon pump deserve further investigation as they are associated with GI complications.

Gastrointestinal complications after cardiac surgery - improved risk stratification using a new scoring model

Gastrointestinal (GI) complications are serious consequences of cardiac surgery. The aim of this study was to develop, evaluate and validate a new risk score model for GI complications after cardiac surgery. The risk score model, named gastrointestinal complication score (GICS), was developed using prospectively collected data from 5593 patients who underwent 5636 cardiac surgical procedures between 1996 and 2001. The model was validated on 1031 cardiac surgery patients between 2005 and 2006. The scoring system's ability to predict GI complications was estimated by receiver operating characteristic (ROC)-curves and Hosmer-Lemeshow test. Fifty GI complications were identified in 47 patients (0.8%) in the developmental data set and eight (0.8%) in the validation data set. The ROC area in the developmental data set was 0.81 with a good calibration estimated by Hosmer-Lemeshow test (P=0.89). In the validation data set, the area under the curve was 0.83. The estimated probability for the patient to develop a GI complication after cardiac surgery at a GICS >or=15 is >20% and at a GICS <or=5 is <0.4%. Risk stratification according to GICS, specifically developed to predict GI complications after cardiac surgery, showed a good predictive ability.