Intraoperative transfusion management, antifibrinolytic therapy, coagulation monitoring and the impact on short-term outcomes after liver transplantation-A systematic review of the literature and expert panel recommendations.

BACKGROUND: Liver transplantation (LT) is frequently complicated by coagulopathy associated with end-stage liver disease (ESLD), that is, often multifactorial. OBJECTIVES: The objective of this systematic review was to identify evidence based intraoperative transfusion and coagulation management strategies that improve immediate and short-term outcomes after LT. METHODS: PRISMA-guidelines and GRADE-approach were followed. Three subquestions were formulated. (Q); Q1: transfusion management; Q2: antifibrinolytic therapy; and Q3: coagulation monitoring. RESULTS: Sixteen studies were included for Q1, six for Q2, and 10 for Q3. Q1: PRBC and platelet transfusions were associated with higher mortality. The use of prothrombin complex concentrate (PCC) and fibrinogen concentrate (FC) were not associated with reductions in intraoperative transfusion or increased thrombotic events. The use of cell salvage was not associated with hepatocellular carcinoma (HCC) recurrence or mortality. Cell salvage and transfusion education significantly decreased blood product transfusions. Q2: Epsilon-aminocaproic acid (EACA) and tranexamic acid (TXA) were not associated with decreased blood product transfusion, improvements in patient or graft survival, or increases in thrombotic events. Q3: Viscoelastic testing (VET) was associated with decreased allogeneic blood product transfusion compared to conventional coagulation tests (CCT) and is likely to be cost-effective. Coagulation management guided by VET may be associated with increases in FC and PCC use. CONCLUSION: Q1: A specific blood product transfusion practice is not recommended (QOE; low | Recommendation; weak). Cell salvage and educational interventions are recommended (QOE: low | Grade of Recommendation: moderate). Q2: The routine use of antifibrinolytics is not recommended (QOE; low | Recommendation; weak). Q3: The use of VET is recommended (QOE; low-moderate | Recommendation; strong).

A brief history of liver transplantation and transplant anesthesia.

In this review, we describe the major milestones in the development of organ transplantation with a specific focus on hepatic transplantation. For many years, the barriers preventing successful organ transplantation in humans seemed insurmountable. Although advances in surgical technique provided the technical ability to perform organ transplantation, limited understanding of immunology prevented successful organ transplantation. The breakthrough to success was the result of several significant discoveries between 1950 and 1980 involving improved surgical techniques, the development of effective preservative solutions, and the suppression of cellular immunity to prevent graft rejection. After that, technical innovations and laboratory and clinical research developed rapidly. However, these advances alone could not have led to improved transplant outcomes without parallel advances in anesthesia and critical care. With increasing organ demand, it proved necessary to expand the donor pool, which has been achieved with the use of living donors, split grafts, extended criteria organs, and organs obtained through donation after cardiac death. Given this increased access to organs and organ resources, the number of transplantations performed every year has increased dramatically. New regulatory organizations and transplant societies provide critical oversight to ensure equitable organ distribution and a high standard of care and also perform outcome analyses. Establishing dedicated transplant anesthesia teams results in improved organ transplantation outcomes and provides a foundation for developing new standards for other subspecialties in anesthesiology, critical care, and medicine overall. Through a century of discovery, the success we enjoy at the present time is the result of the work of well-organized multidisciplinary teams following standardized protocols and thereby saving thousands of lives worldwide each year. With continuing innovation, the future is bright.

Hyponatremia and Liver Transplantation: A Narrative Review.

Hyponatremia is a common electrolyte disorder in patients with end-stage liver disease (ESLD) and is associated with increased mortality on the liver transplantation (LT) waiting list. The impact of hyponatremia on outcomes after LT is unclear. Ninety-day and one-year mortality may be increased, but the data are conflicting. Hyponatremic patients have an increased rate of complications and longer hospital stays after transplant. Although rare, osmotic demyelination syndrome (ODS) is a feared complication after LT in the hyponatremic patient. The condition may occur when the serum sodium (sNa) concentration increases excessively during or after LT. This increase in sNa concentration correlates with the degree of preoperative hyponatremia, the amount of intraoperative blood loss, and the volume of intravenous fluid administration. The risk of developing ODS after LT can be mitigated by avoiding large perioperative increases in sNa concentration . This can be achieved through measures such as carefully increasing the sNa pretransplant, and by limiting the intravenous intra- and postoperative amounts of sodium infused. SNa concentrations should be monitored regularly throughout the entire perioperative period.

Management of Patients With Non-alcoholic Steatohepatitis Undergoing Liver Transplantation: Considerations for the Anesthesiologist.

Non-alcoholic fatty liver disease (NAFLD) currently affects more than 25% of the world population and is rising. NAFLD can progress to non-alcoholic steatohepatitis that is associated with hepatic inflammation and fibrosis and can result in cirrhosis with subsequent liver failure. Non-alcoholic steatohepatitis (NASH) has now emerged as one of the leading etiologies for a liver transplant among adults in the United States. Given the rising incidence of liver transplants in patients with NASH-related cirrhosis, it is essential for anesthesiologists to be familiar with this condition as well as with NASH-related comorbidities and perioperative complications. Not only is NASH linked to metabolic syndrome, but it also is independently associated with cardiovascular disease, renal and thyroid dysfunction, obstructive sleep apnea (OSA), and a hypercoagulable state. The association with these conditions can affect the perioperative outcome of these patients, particularly because of increased mortality from major adverse cardiovascular events and sepsis. In order to decrease the perioperative morbidity and mortality of patients with NASH undergoing a liver transplant, a multidisciplinary approach to their perioperative management is essential, along with careful preoperative evaluation and aggressive intraoperative and postoperative monitoring. The focus of this review article is to provide a comprehensive overview of challenges associated with liver transplants in patients with NASH and to provide suggestions for appropriate patient selection and perioperative management.

Decline in Functional Status While on the Waiting List Predicts Worse Survival After Lung Transplantation.

OBJECTIVES: To determine if decreases in the Karnofsky Performance Score (KPS) while on the waitlist predict decreased survival after lung transplantation (LTx). DESIGN: A retrospective evaluation of the United Network for Organ Sharing database. The KPS was evaluated at the time of listing for transplant and at the time of transplantation. Group I consisted of patients having a decrease in KPS during the time on the waiting list (from the time of listing to the time of transplant), and Group II consisted of patients whose KPS stayed the same or increased during the same period. The authors used propensity-score weighting for comparisons of these groups. SETTING: Retrospective observational database review. PARTICIPANTS: Adult patients undergoing lung transplantation. INTERVENTIONS: None. Patients were stratified according to a change in their KPS. MEASUREMENTS AND MAIN RESULTS: Patient and graft survival of patients with decreasing or not decreasing KPS were compared. Of the 27,558 subjects included in the analysis, 17,986 (65%) had worsening KPS, which was associated with worse graft (p = 0.0003) and patient (p = 0.0019) survival after LTx. Using multivariate regression, a decrease in KPS of ≥40 was associated with decreased survival, and an increase of ≥40 was associated with improved survival (HR = 1.245, 95% CI [1.181-1.312], p < 0.0001 and HR = 0.866, 95% CI [0.785, 0.955], respectively). Among patients with a KPS <40 at the time of transplant, those with a decrease in KPS of ≥40 had decreased graft and patient survival compared with those with a smaller decrease (p = 0.0002 and p = 0.0021, respectively). CONCLUSIONS: Deterioration of KPS on the waiting list for LTx is associated with significantly greater postoperative mortality in patients after LTx. These results should be taken into consideration when allocating organs. Strategies to increase or to prevent a decrease in KPS before LTx should be evaluated.

A decline in functional status while awaiting liver transplantation is predictive of increased post-transplantation mortality.

BACKGROUND: Functional status (FS) is dynamic and changes over time. We examined how changes in FS while awaiting liver transplantation influence post-transplant outcomes. METHODS: Data on adult liver transplants performed in the United States during the MELD era were obtained through September 2020. Patient and graft survival were compared between groups with no change or improved FS, and those with worsening FS. RESULTS: Of the 90,210 transplant recipients included in the analysis, 39,193 (43%) had worsening FS, which was associated with longer waiting-list time (187 vs. 329 days, p < 0.001) and worse patient survival after liver transplant (1858 vs. 1727 days, p < 0.001). A consistent and dose-dependent relationship was observed for each 10-point decrease in Karnofsky Performance Score and post-transplant survival. Multivariable regression analysis confirmed that a decline in FS was associated with worse patient survival (HR 1.15, p < 0.001). Similar findings were observed for graft survival. CONCLUSION: A decline in FS on the waiting-list is associated with significantly greater post-liver transplant mortality in recipients. These results should be taken into consideration when allocating organs and determining transplant candidacy. Strategies to optimize FS prior to transplantation should be prioritized as even subtle decreases in FS are associated with inferior post-transplantation outcomes.

Development of a Model to Predict Portal Vein Thrombosis in Liver Transplant Candidates: The Portal Vein Thrombosis Risk Index.

Portal vein thrombosis (PVT) is associated with inferior pretransplantation and posttransplantation outcomes. We aimed to create a predictive model to risk stratify transplant candidates for PVT. Data on adult transplants in the United States during the Model for End-Stage Liver Disease (MELD) era through September 2016 were reviewed. We constructed and validated a scoring system composed of routine, readily available clinical information to predict the development of incident PVT at 12 months from transplantation listing. A total of 66,568 liver transplant candidates were dichotomized into 2 groups to construct (n = 34,751) and validate (n = 31,817) a scoring system. In general, the derivation and validation cohorts were clinically similar. Although nonalcoholic steatohepatitis was a significant predictor of incident PVT (hazard ratio, 1.29; 95% confidence interval, 1.08-1.54; P < 0.001), age, MELD score, and moderate-to-severe ascites were also associated with increased risk. African American race was associated with decreased risk. A scoring system (PVT risk index [RI]) of these 5 variables had an area under the curve of 0.71 and 0.70 in both derivation and validation cohorts, respectively. By applying the low cutoff score of 2.6, incident PVT could be accurately excluded (negative predictive value 94%). Using the high cutoff score of 4.6 (positive predictive value 85%), PVT could be diagnosed with high accuracy. The PVT-RI predicts which candidates awaiting lifesaving liver transplantation will and will not develop future PVT. Although this scoring system will require prospective validation, it provides a powerful new tool for the clinician when risk stratifying cirrhosis patients prior to liver transplantation for future PVT development.

Assessment and management of coagulopathy in critically-ill patients with liver failure.

PURPOSE OF REVIEW: This review provides insight into our current understanding of the pathophysiology and treatment of coagulopathy associated with liver failure, and bleeding risk assessment. RECENT FINDINGS: Patients with end-stage liver disease (ESLD) have a rebalanced coagulation profile and are at risk for both excessive clotting and bleeding. Hypercoagulability is associated with profound endothelial dysfunction and an increased concentration of liver-independent coagulation factors. Because of this rebalanced coagulation profile, standard laboratory tests have been demonstrated to be ineffective in either predicting and/or guiding the management of coagulopathy. Viscoelastic testing, however, is able to provide a dynamic assessment of clot formation in whole blood and has been demonstrated to be invaluable in both monitoring and management of coagulation problems associated with liver failure. More recently, there is increasing interest in thrombin generation tests to monitor coagulation in patients with ESLD.Multiple institutional protocols for prophylaxis and treatment of ESLD-related thromboses have been developed. High-quality studies evaluating these approaches are lacking. SUMMARY: Patients with ESLD are at risk for excessive bleeding and clotting. Treatment of any significant coagulopathy should not be based solely on standard laboratory tests. Thrombosis prophylaxis has to be considered in susceptible populations.

The "Ice Age" in Cardiac Surgery: Evolution of the "Siberian" Method of Brain Protection During Deep Hypothermic Perfusionless Circulatory Arrest.

Deep hypothermic perfusionless circulatory arrest was the first practical neuroprotective technique used for open-heart surgery. It was refined at the Novosibirsk Medical Research Center in Siberia and was actively used from the mid-1950s until 2001.This review describes the development of this technique and its contribution to our understanding of the dynamic changes in human physiology during induced hypothermia for circulatory arrest without extracorporeal perfusion. Deep hypothermic perfusionless circulatory arrest was an important stepping stone in the development of modern approaches in neuroprotection and monitoring during cardiac surgery.

Perioperative thrombotic complications associated with pediatric liver transplantation: a UNOS database evaluation.

BACKGROUND: This retrospective UNOS database evaluation analyzes the prevalence of preoperative portal vein thromboses (PVT), and postoperative thromboses leading to graft failure in pediatric patients undergoing liver transplantation (LT). METHODS: The evaluation was performed in three age groups: I (0-5), II (6-11), III (12-18) years old. Factors predictive of pre- and postoperative thromboses were analyzed. RESULTS: Between 2000 and 2015, 8982 pediatric LT were performed in the US. Of those, 390 patients had preoperative PVT (4.3%), and 396 (4.4%) had postoperative thromboses. The prevalence of both types of thromboses was less in Group III than in the other two groups (3.20% vs 4.65%, p = 0.007 and 1.73% vs. 5.13%, p < 0.001, respectively). The prevalence of postoperative thromboses was significantly higher in Group I than in the other two groups (5.49% vs. 2.51%, p < 0.001). Preoperative PVT was independently associated with postoperative thromboses (OR = 1.7, p = 0.02). Children less than 5 years of age were more likely to develop postoperative thromboses leading to graft failure (OR = 2.9, p < 0.001). CONCLUSION: Younger children undergoing LT are prone to pre-and postoperative thrombotic complications. Preoperative PVT at the time of transplantation was independently associated with postoperative thromboses. Perioperative antithrombotic therapy should be considered in pediatric patients undergoing LT.

Acute heart failure after Orthotopic liver transplantation: a case series from one center.

BACKGROUND: Patients undergoing liver transplantation (LT) can develop acute heart failure (HF) in the postoperative period despite having had a normal cardiac evaluation prior to surgery. End-stage liver disease is often associated with underlying cardiac dysfunction which, while not identified during preoperative testing, manifests itself during or immediately after surgery. CASE PRESENTATION: We describe three cases of non-ischemic acute HF developing shortly after LT in patients who had a normal preoperative cardiac evaluation. The challenges associated with both diagnosis and management of acute HF in the setting of a newly implanted graft will be discussed. CONCLUSIONS: Diastolic dysfunction, QTc interval prolongation, and an increase in BNP may be predictive of postoperative HF. Current recommendations for preoperative cardiovascular evaluation of transplant candidates does not include studies examining these risk factors and should be revised. Further investigations are necessary to evaluate these findings.

Liver graft preservation using perfluorocarbon improves the outcomes of simulated donation after cardiac death liver transplantation in rats.

The outcomes of liver transplantation (LT) from donation after cardiac death (DCD) donors remain poor due to severe warm ischemia injury. Perfluorocarbon (PFC) is a novel compound with high oxygen carrying capacity. In the present study, a rat model simulating DCD LT was used, and the impact of improved graft oxygenation provided by PFC addition on liver ischemia/reperfusion injury (IRI) and survival after DCD LT was investigated. Orthotopic liver transplants were performed in male Lewis rats, using DCD liver grafts preserved with cold University of Wisconsin (UW) solution in the control group and preserved with cold oxygenated UW solution with addition of 20% PFC in the PFC group. For experiment I, in a 30-minute donor warm ischemia model, postoperative graft injury was analyzed at 3 and 6 hours after transplantation. For experiment II, in a 50-minute donor warm ischemia model, the postoperative survival was assessed. For experiment I, the levels of serum aspartate aminotransferase, alanine aminotransferase, hyaluronic acid, malondialdehyde, and several inflammatory cytokines were significantly lower in the PFC group. The hepatic expression levels of tumor necrosis factor α and interleukin 6 were significantly lower, and the expression level of heme oxygenase 1 was significantly higher in the PFC group. Histological analysis showed significantly less necrosis and apoptosis in the PFC group. Sinusoidal endothelial cells and microvilli of the bile canaliculi were well preserved in the PFC group. For experiment II, the postoperative survival rate was significantly improved in the PFC group. In conclusion, graft preservation with PFC attenuated liver IRI and improved postoperative survival. This graft preservation protocol might be a new therapeutic option to improve the outcomes of DCD LT. Liver Transplantation 23 1171-1185 2017 AASLD.

African Americans have a lower prevalence of portal vein thrombosis at the time of liver transplantation.

BACKGROUND: Perioperative vascular thrombotic events in patients undergoing liver transplantation (LT) are associated with significant morbidity and mortality. METHODS: In this retrospective UNOS database analysis, we evaluated the prevalence of portal vein thrombosis (PVT) and factors contributing to PVT development in different ethnic groups. RESULTS: Of the 47 953 LT performed between 2002 and 2015, we identified 3642 cases of PVT. African Americans (AA) had a significantly lower prevalence of PVT compared to other ethnic groups (p = 0.0001). Multivariable regression analysis confirmed that AA were less likely than other ethnicities to have PVT (OR = 0.6). AA cohort was more likely to have infectious or autoimmune causes of liver failure (OR = 1.6, 1.7 respectively) as well as higher creatinine and INR compared to other groups (OR = 1.6, 1.3 respectively). AA's were less likely to have encephalopathy, ascites, or variceal bleeding, which might indicate lower portal pressures. AA's were listed for LT later than other ethnicities and had both a lower functional status and higher MELD score at the time of registration. DISCUSSION: AA's had a significantly lower prevalence of preoperative PVT despite having a greater number of factors predisposing to thrombosis. This predisposition should be considered before instituting perioperative antithrombotic therapy.

Portal Hypertension: An Underestimated Entity?

OBJECTIVE: The aim of this study is to evaluate portal hypertension as an independent risk factor in general surgical procedures. BACKGROUND: Data on the impact of portal hypertension in general surgical outcomes has been limited. Published literature has focused mainly on its effect in liver surgery. The Child Pugh score and Model for End Stage Liver Disease are utilized for surgical risk assessment in liver disease but they do not accurately reflect degree of portal hypertension. METHODS: From 2005 to 2012, patients with esophageal varices (EV) in the National Surgical Quality Improvement Program (NSQIP) formed the portal hypertension cohort, and were case matched to patients without esophageal varices (NEV) based on sex, age, surgery type, and year of operation. Thirty day mortality and morbidity were analyzed using generalized estimating equations for binary outcomes. EV patients were also dichotomized by Model for End Stage Liver Disease (MELD) score (≤15 vs >15) and compared with NEV patients. RESULTS: One thousand five hundred and seventy-four EV patients were matched to 3148 NEV patients. In multivariable analysis, EV patients had a 3.01 higher odds of 30 day mortality (P < 0.001) and 1.28 higher odds of complications (P < 0.001) compared with NEV patients. EV patients with MELD >15 had 4.64 higher odds of death within 30 days (P < 0.001) and had 1.75 higher odds of complications within 30 days (P < 0.001) compared with NEV patients; EV patients with MELD 15 or less had 1.95 higher odds of 30 day mortality (P < 0.001) compared with NEV patients. CONCLUSIONS: Portal hypertension is associated with a significant mortality and morbidity risk in general surgery, and should not be underestimated even in patients with MELD 15 or less where the early mortality risk remained significant.

Autoimmune conditions are associated with perioperative thrombotic complications in liver transplant recipients: A UNOS database analysis.

BACKGROUND: End stage liver disease (ESLD) is associated with significant thrombotic complications. In this study, we attempted to determine if patients with ESLD, due to oncologic or autoimmune diseases, are susceptible to thrombosis to a greater extent than patients with ESLD due to other causes. METHODS: In this retrospective study, we analyzed the UNOS database to determine the incidence of thrombotic complications in orthotopic liver transplant (OLT) recipients with autoimmune and oncologic conditions. Between 2000 and 2012, 65,646 OLTs were performed. We found 4,247 cases of preoperative portal vein thrombosis (PVT) and 1,233 cases of postoperative vascular thrombosis (VT) leading to graft failure. RESULTS: Statistical evaluation demonstrated that patients with either hepatocellular carcinoma (HCC) or autoimmune hepatitis (AIC) had a higher incidence of PVT (p = 0.05 and 0.03 respectively). Patients with primary biliary cirrhosis (PBC), primary sclerosing cholangitis (PSC) and AIC had a higher incidence of postoperative VT associated with graft failure (p < 0.0001, p < 0.0001, p = 0.05 respectively). Patients with preoperative PVT had a higher incidence of postoperative VT (p < 0.0001). Multivariable logistic regression demonstrated that patients with AIC, and BMI ≥40, having had a transjugular intrahepatic portosystemic shunt, and those with diabetes mellitus were more likely to have preoperative PVT: odds ratio (OR)(1.36, 1.19, 1.78, 1.22 respectively). Patients with PSC, PBC, AIC, BMI ≤18, or with a preoperative PVT were more likely to have a postoperative VT: OR (1.93, 2.09, 1.64, 1.60, and 2.01, respectively). CONCLUSION: Despite the limited number of variables available in the UNOS database potentially related to thrombotic complications, this analysis demonstrates a clear association between autoimmune causes of ESLD and perioperative thrombotic complications. Perioperative management of patients at risk should include strategies to reduce the potential for these complications.

Phenylephrine infusion for spinal-induced hypotension in elective cesarean delivery: Does preload make a difference?

BACKGROUND AND AIMS: Patients undergoing elective cesarean delivery (CD) have a high-risk of spinal-induced hypotension (SIH). We hypothesized that a colloid preload would further reduce SIH when compared with a crystalloid preload. MATERIAL AND METHODS: Eighty-two healthy parturients undergoing elective CD were included in the study. Patients were randomly assigned to two groups (41 patients in each group) to receive either Lactated Ringer's solution (1500 ml) or hydroxyethyl starch (6% in normal saline, 500 ml) 30 min prior to placement of spinal anesthesia. All patients were treated with a phenylephrine infusion (100 mcg/min), titrated during the study. RESULTS: There was no statistical difference between groups with regards to the incidence of hypotension (10.8% in the colloid group vs. 27.0% in the crystalloid group, P = 0.12). There was also no difference between groups with respect to bradycardia, APGAR scores, and nausea and vomiting. Significantly less phenylephrine (1077.5 ± 514 mcg) was used in the colloid group than the crystalloid group (1477 ± 591 mcg, P = 0.003). CONCLUSION: The preload with 6% of hydroxyethyl starch before CD might be beneficial for the prevention of SIH.

Hepatic resection is associated with reduced postoperative opioid requirement.

BACKGROUND AND AIMS: Postoperative pain can significantly affect surgical outcomes. As opioid metabolism is liver-dependent, any reduction in hepatic volume can lead to increased opioid concentrations in the blood. The hypothesis of this retrospective study was that patients undergoing open hepatic resection would require less opioid for pain management than those undergoing open pancreaticoduodenectomy. MATERIAL AND METHODS: Data from 79 adult patients who underwent open liver resection and eighty patients who underwent open pancreaticoduodenectomy at our medical center between January 01, 2010 and June 30, 2013 were analyzed. All patients received both general and neuraxial anesthesia. Postoperatively, patients were managed with a combination of epidural and patient-controlled analgesia. Pain scores and amount of opioids administered (morphine equivalents) were compared. A multivariate lineal regression was performed to determine predictors of opioid requirement. RESULTS: No significant differences in pain scores were found at any time point between groups. Significantly more opioid was administered to patients having pancreaticoduodenectomy than those having a hepatic resection at time points: Intraoperative (P = 0.006), first 48 h postoperatively (P = 0.001), and the entire length of stay (LOS) (P = 0.002). Statistical significance was confirmed after controlling for age, sex, body mass index, and American Society of Anesthesiologists physical status classification (adjusted P = 0.006). Total hospital LOS was significantly longer after pancreaticoduodenectomy (P = 0.03). A multivariate lineal regression demonstrated a lower opioid consumption in the hepatic resection group (P = 0.03), but there was no difference in opioid use based on the type of hepatic resection. CONCLUSION: Patients undergoing open hepatic resection had a significantly lower opioid requirement in comparison with patients undergoing open pancreaticoduodenectomy. A multicenter prospective evaluation should be performed to confirm these findings.

Myocardial perfusion imaging is an effective screening test for coronary artery disease in liver transplant candidates.

A reliable screening test for coronary artery disease (CAD) in liver transplant (LT) candidates with end-stage liver disease is essential because a high percentage of perioperative mortality and morbidity is CAD-related. In this study, the effectiveness of myocardial perfusion imaging (MPI) for identification of significant CAD in LT candidates was evaluated. Records of 244 patients meeting criteria for MPI were evaluated: 74 met inclusion criteria; 40 had a positive MPI and cardiology follow-up; 27 had a negative MPI and underwent LT; and seven had a negative MPI and then had coronary angiography or a significant cardiac event. A selective MPI interpretation strategy was established where MPI-positive patients were divided into high, intermediate, and low CAD risk groups. The overall incidence of CAD in this study population was 5.1% and our strategy resulted in PPV 20%, NPV 94%, sensitivity 80%, and specificity 50% for categorizing CAD risk. When applied only to the subset of patients categorized as high CAD risk, the strategy was more effective, with PPV 67%, NPV 97%, sensitivity 80%, and specificity 94%. We determined that renal dysfunction was an independent predictive factor for CAD (p < 0.0001, odds ratio = 8.1), and grades of coronary occlusion correlated significantly with chronic renal dysfunction (p = 0.0079).