Predictive value of C-reactive protein for major postoperative complications following off-pump coronary artery bypass surgery: prospective and observational trial

The Value of Biomarkers in Major Cardiovascular Surgery Necessitating Cardiopulmonary Bypass

The use of biomarkers in cardiovascular surgery is an evolving field with promising potential; however, current research remains largely limited, requiring further validation for routine clinical application. This review explores the application of biomarkers in cardiovascular surgery, focusing on heart failure, cardiac ischemia, and organ dysfunction, including renal, cerebral, pulmonary, and splanchnic impairments. Additionally, it examines the significance of biomarkers in assessing the inflammatory state and oxidative stress during the perioperative period, particularly in the context of major surgical trauma and cardiopulmonary bypass (CPB). From January 2018 to June 2024, we reviewed 133 studies and four systematic reviews and meta-analyses using the Medline, Embase, and Central databases, screening for pre- or postoperative biomarker levels in patients undergoing cardiac surgery. Outcomes of interest were postoperative mortality, nonfatal myocardial infarction, stroke, congestive heart failure, and major adverse cardiovascular events (MACEs). Studies reporting multivariable-adjusted risk estimates were included. The findings revealed that cardiac troponins (cTns) and creatine kinase isoenzyme MB (CK-MB) remain the most widely utilized biomarkers for assessing myocardial injury post-surgery. These elevated biomarker levels were consistently associated with an increased risk of postoperative complications, including low cardiac output syndrome, prolonged ventilation, and mortality. Emerging biomarkers, such as heart-type fatty acid-binding protein (h-FABP) and high-sensitivity C-reactive protein (hs-CRP), demonstrated promising early detection and risk stratification results. In particular, h-FABP increased rapidly within one hour of myocardial injury, peaking at 4-6 hours and returning to baseline within 24 hours. This rapid clearance makes h-FABP a valuable tool for early myocardial injury detection, potentially allowing for timely interventions. Inflammatory biomarkers, including hs-CRP and pentraxin 3 (PTX3), were found to be associated with poor outcomes, such as increased morbidity and mortality. Elevated preoperative levels of these markers were indicative of a heightened inflammatory response, correlating with worse postoperative recovery and higher rates of complications. Furthermore, the neutrophil-to-lymphocyte ratio (NLR) emerged as a cost-effective and easily accessible predictor of postoperative outcomes. Elevated NLR values were linked to an increased risk of adverse events, including prolonged ventilation, low cardiac output syndrome, and overall mortality. Further, the practicality of measuring NLR through routine blood tests makes it viable for widespread clinical use. In conclusion, integrating biomarkers in cardiovascular surgery significantly advances predicting postoperative outcomes for cardiac surgery patients. Therefore, it is essential to categorize these biomarkers into two distinct groups in the future, inflammatory and non-inflammatory (related to organ damage), to improve understanding and enhance their clinical applicability. Future research should focus on standardizing the use of these biomarkers and exploring their combined predictive power to enhance risk stratification and improve patient prognosis.

Associations of Inflammatory Biomarkers With the Risk of Morbidity and Mortality After Cardiac Surgery: A Systematic Review and Meta-analysis

BACKGROUND

Although inflammatory biomarkers have been associated with cardiovascular events in nonsurgical settings, these associations have not been systematically addressed in patients undergoing cardiac surgery. This review aimed to evaluate the relationships of inflammatory markers with mortality and adverse cardiovascular events in patients undergoing cardiac surgery.

METHODS

Medline, Embase, and Central databases were systematically searched for studies reporting pre- or postoperative levels of inflammatory biomarkers in patients undergoing cardiac surgery. Outcomes of interest were postoperative mortality, nonfatal myocardial infarction, stroke, congestive heart failure, and major adverse cardiovascular events (MACE). Studies reporting multivariable adjusted risk estimates were included. Risk estimates were pooled with the use of random-effects models and reported as summary odds ratios (ORs).

RESULTS

Among 14,465 citations identified, 29 studies including 29,401 participants met the eligibility criteria. The average follow-up time after surgery was 31 months. Preoperative C-reactive protein (CRP) levels were associated with an increased risk of all-cause mortality (OR 1.88, 95% CI 1.60-2.20; I2 = 19%; 11 studies) and MACE (OR 1.73, 95% CI 1.34-2.24; I2 = 0%; 3 studies). CRP levels measured on postoperative day 6 (OR 7.4, 95% CI 2.90-18.88, 1 study) and day 10 (OR 11.8, 95% CI 3.50-39.78, 1 study) were associated with a higher risk of all-cause mortality. Less, but overall similar, information was available for other inflammatory biomarkers.

CONCLUSIONS

In this large meta-analysis, inflammatory biomarkers measured before or after cardiac surgery were associated with mortality and adverse cardiovascular outcomes in patients undergoing cardiac surgery.

The ımportance of ınflammatory parameters ın predıctıng deep sternal wound ınfectıons after open heart surgery

OBJECTIVE

The aim of this study was to investigate the relationship between the development of deep sternal wound infection after open heart surgery and inflammatory parameters obtained from routine biochemical tests.

METHODS

A total of 280 patients who underwent cardiac surgery with median sternotomy between January 2015 and January 2020 were examined retrospectively. Patients who developed deep sternal wound infection were identified as "Group 1," and those who did not develop deep sternal wound infection were identified as "Group 2."

RESULTS

There were 70 patients with a mean age of 61.6±9.9 years in Group 1 and 210 patients with a mean age of 62.7±9.8 years in Group 2. As a result of the analysis, it was found that the presence of concomitant chronic obstructive pulmonary disease, concomitant diabetes mellitus, blood and blood product transfusion, postoperative 2nd day C-reactive protein, postoperative 1st day neutrophil-to-lymphocyte ratio, and delta neutrophil-to-lymphocyte ratio was found as independent predictive factors of postoperative deep sternal wound infection development (p=0.043, p=0.012, p=0.029, p=0.009, p=0.002, and p<0.001; respectively). As a predictor of deep sternal wound infections development, postoperative 1st day neutrophil-to-lymphocyte ratio cutoff value was 11.2 (area under the curve [AUC] 0.598; p=0.014; 60% sensitivity, and 65.2% specificity), and delta neutrophil-to-lymphocyte ratio cutoff value was 9.6 (AUC 0.716; p<0.001; 57.1% sensitivity, and 73.8% specificity).

CONCLUSIONS

Deep sternal wound infection development can be predicted with inflammatory parameters such as neutrophil-to-lymphocyte ratio and C-reactive protein that are obtained from cheap and easily available routine biochemical tests.

Sternal wound infections after sternotomy: risk factors, prevention and management

A serious complication after cardiac surgery is sternal wound infection. Although incidence rates vary worldwide, this complication raises significant concern in a certain patient demographic. This article uses risk assessment strategies to identify a high-risk patient profile and draws parallels with positive predictors in the preoperative, intraoperative and postoperative setting. It describes the complexity of sternal wound infections and highlights guidelines on detection and treatment. The optimal goal of this article is to help minimise the incidence of sternal wound complications after sternotomy by discussing recommendations for preoperative, intraoperative and postoperative preventive measures.

A novel case of impaired C-reactive protein response following open-heart surgery: A case report and review of the literature

BACKGROUND

C-reactive protein (CRP) is expected to increase in response to a range of inflammatory stimuli such as infections or extensive tissue trauma.

CASE REPORT

We present a novel case of severely impaired CRP response following NSTEMI, influenza A infection and open-heart surgery in which serum CRP concentrations remained < 1 mg/L during an observational period of 28 days.

CONCLUSION

To our knowledge, no previous publications exists describing patients with a lack of CRP response following cardiothoracic surgery. We believe this to be a novel finding warranting further investigations regarding the etiology and prevalence of this phenomenon.

Preoperative C-reactive protein as a predictor of postoperative acute kidney injury in patients undergoing coronary artery bypass grafting

C-reactive protein is a well-known marker of inflammation and may be preoperatively elevated in the absence of infection in adult cardiac surgery patients, indicating a baseline inflammatory process. We conducted a literature search to assess the available evidence on whether there is an association between preoperative C-reactive protein and acute kidney injury after coronary artery bypass grafting. Included only were observational studies which investigated this association. We excluded abstracts, case reports, animal studies and articles in languages other than English. Altogether, 199 papers were retrieved from the search strategy reported, of which 6 studies were included in the final review. The study types, publication details, patient groups and key results are tabulated. A qualitative assessment of these papers was conducted. We conclude that there is some evidence to support the association between high preoperative C-reactive protein level and postoperative acute kidney injury and complications after coronary artery bypass grafting. Owing to variability in acute kidney injury definitions and C-reactive protein levels for different cohorts in the observational studies reviewed, it is unclear from current evidence what serum C-reactive protein cut-off level is significantly associated with postoperative acute kidney injury. Further evidence is needed to investigate whether raised preoperative C-reactive protein in the absence of an infective cause could have a role in risk prediction models for cardiac surgery-associated acute kidney injury.

Predictors of early postoperative pneumonia after oncologic surgery with the patients receiving professional oral health care: A prospective, multicentre, cohort study

This study was a prospective, multicentre, cohort study on 685 patients who had undergone oncologic surgery. The patients were divided into two groups according to the presence or absence of postoperative pneumonia. The two groups were compared with respect to their background, index operation, food eaten, oral condition, contents of oral care and dental treatment, laboratory data, and bacterial flora. All postoperative pneumonias occurred in six cases within four days postoperatively. The multivariable logistic regression analysis showed that preoperative serum C-reactive protein was the strongest predictor of postoperative pneumonia. In addition, decreased postoperative Candida albicans colonies was an effective predictor of postoperative pneumonia. For patients with predictors of postoperative pneumonia, perioperative strategies for its prevention should be considered in addition to professional oral health care. This study was approved by the National Hospital Organization's Central Ethics Review Board and was also approved by the directors of the participating institutions.

Perioperative Acute Kidney Injury: Risk Factors and Predictive Strategies

Acute kidney injury (AKI) is a common complication in surgical patients and is associated with increases in mortality, an increased risk for chronic kidney disease and hemodialysis after discharge, and increased cost. Better understanding of the risk factors that contribute to perioperative AKI has led to improved AKI prediction and will eventually lead to improved prevention of AKI, mitigation of injury when AKI occurs, and enhanced recovery in patients who sustain AKI. The development of advanced clinical prediction scores for AKI, new imaging techniques, and novel biomarkers for early detection of AKI provides new tools toward these ends.

The role of preoperative blood parameters to predict the risk of surgical site infection

BACKGROUND

Routine preoperative blood work is not recommended but selected biochemical markers may predict the risk of surgical site infection (SSI). This study examines the association between preoperative biochemical markers and the risk of SSI.

METHODS

This observational cohort study, nested in a randomized controlled trial, was conducted at two tertiary referral centers in Switzerland.

RESULTS

122 (5.8%) of 2093 patients experienced SSI. Preoperative increasing levels of albumin (OR 0.93), CRP (OR 1.34), hemoglobin (OR 0.87) and eGFR (OR 0.90) were significantly associated with the odds of SSI. The same accounts for categorized parameters. The highest area under the curve from ROC curves was 0.62 for albumin. Positive predictive values ranged from 6.4% to 9.5% and negative predictive values from 94.8% to 95.7%. The association of CRP, mildly and moderately decreased eGFR and hemoglobin with the odds of SSI remained significant on multivariate analysis.

CONCLUSIONS

Our results do not support generally delaying elective surgery based on preoperative blood results. However, it may be considered in situations with potentially severe sequelae of SSI.

[Relationship between hyperuricemia and adverse events in patients aged 40 years or older receiving rheumatic aortic valve replacement]

OBJECTIVE

To explore the prognostic value of hyperuricemia for adverse events in patients >40 years old receiving valve replacement surgery for rheumatic aortic valve disease.

METHDS

Consecutive middle-aged and elderly patients receiving aortic valve replacement surgery for rheumatic aortic valve disease between March, 2009 and July, 2013 were recruited in this study. The patients were divided into hyperuricemic group and normouricemic group based on their serum levels of uric acid, and the clinical data and adverse events within 1 year after the surgery were compared between the 2 groups.

RESULTS

A total of 632 consecutive patients were recruited, including 381 patients with hyperuricemia and 251 with normouricemia. The in-hospital mortality rate was significantly higher in hyperuricemic group than in normouricemic group (7.6% vs 2.0%, P=0.002). Serum uric acid levels were negatively correlated with eGFR (r=-0.421, P<0.001) and positively correlated with C-reactive protein level (r=0.093, P=0.025). Multivariate analysis showed that hyperuricemia was independently associated with the in-hospital mortality (OR=3.07, 95%CI: 1.13-8.37, P=0.028) and mortality at 1 year after the surgery (HR=3.14, 95%CI: 1.30-7.62, P=0.011) after adjusting for potential risk factors including age, NYHA III-IV and postoperative acute kidney injury (AKI). Kaplan-Meier analysis showed that the cumulative rate of 1-year mortality after surgery was significantly higher in patients with hyperuricemia (Log-rank=11.73, P=0.001).

CONCLUSION

Hyperuricemia is a predictor of in-hospital and one-year mortality in middle-aged and elderly patients following aortic valve replacement surgery for rheumatic aortic valve disease.

Simple blood and urinary parameters measured at ICU admission may sign for AKI development in the early postoperative period: a retrospective, exploratory study

Recent studies have suggested that some blood physicochemical and urinary biochemical parameters have a standardized behavior during acute kidney injury (AKI) development. The changes in these parameters frequently begin to occur before significant rises in serum creatinine (sCr) and may help in identifying patients with more subtle decreases in glomerular filtration rate (GFR). Surgical patients have an increased risk of AKI but renal impairment is usually not evident at ICU admission. We hypothesized that the surgical patients who have AKI diagnosed in the early postoperative period have an impaired GFR since ICU admission, indirectly inferred by alterations in these blood physicochemical and urinary biochemical parameters even in the presence of a still normal sCr. We retrospectively evaluated 112 surgical patients who were categorized according to AKI development during the first 3 ICU days. Twenty-eight patients developed AKI, most of them in the first day (D1) after ICU admission (D0). AKI patients had, at D0, lower serum pH and albumin, higher C - reactive protein (CRP), lower urine sodium (NaU) and fractional excretion of urea (FEUr). Fractional excretion of potassium (FEK) was high in both groups at D0 but remained high in the subsequent days only in AKI patients. Very low CRP and high serum albumin, high NaU and FEUr values at ICU admission had a significant negative predictive value for AKI. We concluded that some easily assessed parameters in blood and urine may help to identify patients with indirect signs of increased inflammatory response and decreased GFR at ICU admission, which could help to predict the risk of postoperative AKI development.

Biomarkers in Coronary Artery Bypass Surgery: Ready for Prime Time and Outcome Prediction?

Coronary artery bypass surgery (CABG) is still one of the most frequently performed surgical procedures all over the world. The results of this procedure have been constantly improved over the years with low perioperative mortality rates, with relatively low complication rates. To further improve these outstanding results, the clinicians focused their attention at biomarkers as outcome predictors. Although biological testing for disease prediction has already been discussed many times, the role of biomarkers in outcome prediction after CABG is still controversial. In this article, we reviewed the current knowledge regarding the role of genetic and dynamic biomarkers and their possible association with the occurrence of adverse clinical outcomes after CABG. We also took into consideration that the molecular pathway activation and the possible imbalance may affect hard outcomes and graft patency. We analyzed biomarkers classified in two different categories depending on their possibility to change over time: genetic markers and dynamic markers. Moreover, we evaluated these markers by dividing them, into sub-categories, such as inflammation, hemostasis, renin–angiotensin, endothelial function, and other pathways. We showed that biomarkers might be associated with unfavorable outcomes after surgery, and in some cases improved outcome prediction. However, the identification of a specific panel of biomarkers or of some algorithms including biomarkers is still in an early developmental phase. Finally, larger studies are needed to analyze broad panel of biomarkers with the specific aim to evaluate the prediction of hard outcomes and graft patency.

Comparison of Plasma and Urine Biomarker Performance in Acute Kidney Injury

Background

New renal biomarkers measured in urine promise to increase specificity for risk stratification and early diagnosis of acute kidney injury (AKI) but concomitantly may be altered by urine concentration effects and chronic renal insufficiency. This study therefore directly compared the performance of AKI biomarkers in urine and plasma.

Methods

This single-center, prospective cohort study included 110 unselected adults undergoing cardiac surgery with cardiopulmonary bypass between 2009 and 2010. Plasma and/or urine concentrations of creatinine, cystatin C, neutrophil gelatinase-associated lipocalin (NGAL), liver fatty acid-binding protein (L-FABP), kidney injury molecule 1 (KIM1), and albumin as well as 15 additional biomarkers in plasma and urine were measured during the perioperative period. The primary outcome was AKI defined by AKIN serum creatinine criteria within 72 hours after surgery.

Results

Biomarkers in plasma showed markedly better discriminative performance for preoperative risk stratification and early postoperative (within 24h after surgery) detection of AKI than urine biomarkers. Discriminative power of urine biomarkers improved when concentrations were normalized to urinary creatinine, but urine biomarkers had still lower AUC values than plasma biomarkers. Best diagnostic performance 4h after surgery had plasma NGAL (AUC 0.83), cystatin C (0.76), MIG (0.74), and L-FAPB (0.73). Combinations of multiple biomarkers did not improve their diagnostic power. Preoperative clinical scoring systems (EuroSCORE and Cleveland Clinic Foundation Score) predicted the risk for AKI (AUC 0.76 and 0.71) and were not inferior to biomarkers. Preexisting chronic kidney disease limited the diagnostic performance of both plasma and urine biomarkers.

Conclusions

In our cohort plasma biomarkers had higher discriminative power for risk stratification and early diagnosis of AKI than urine biomarkers. For preoperative risk stratification of AKI clinical models showed similar discriminative performance to biomarkers. The discriminative performance of both plasma and urine biomarkers was reduced by preexisting chronic kidney disease.

Acute Kidney Injury in the Surgical Patient

Perioperative acute kidney injury (AKI) is a common, morbid, and costly surgical complication. Current efforts to understand and manage AKI in surgical patients focus on prevention, mitigation of further injury when AKI has occurred, treatment of associated conditions, and facilitation of renal recovery. Lesser severity AKI is now understood to be much more common, and more morbid, than was previously thought. The ability to detect AKI within hours of onset would be helpful in protecting the kidney and in preserving renal function, and several imaging and biomarker modalities are currently being evaluated.

Inflammation, Functional Status, and Weight Loss During Recovery From Cardiac Surgery in Older Adults

Objective:

To determine the nutritional, inflammatory, and functional aspects of unintentional weight loss after cardiac surgery that warrant further investigation.

Research Methods and Procedures:

Twenty community-dwelling adults > 65 years old undergoing cardiac surgery (coronary artery bypass graft [CABG] or CABG + valve) were recruited for this prospective longitudinal (preoperative and 4–6 weeks postdischarge) pilot study. Anthropometrics (weight, standing height, and mid-arm and calf circumference), nutritional status (Mini-Nutritional Assessment™ [MNA]), appetite, physical performance (timed chair stand), muscle strength (hand grip) and functional status (basic and instrumental activities of daily living), and inflammatory markers (plasma leptin, ghrelin, interleukin [IL]-6, high-sensitivity[hs] C-reactive protein, and serum albumin and prealbumin) were measured.

Results:

Participants who completed the study ( n = 11 males, n = 3 females) had a mean age 70.21 ± 4.02 years. Of these, 12 lost 3.66 ± 1.44 kg over the study period. Weight, BMI, activities of daily living, and leptin decreased over time ( p < .05). IL-6 increased over time ( p < .05). Ghrelin, hs-CRP, and timed chair stand increased over time in those who underwent combined procedures ( p < .05). Grip strength decreased in those who developed complications ( p = .004). Complications, readmission status, and lowered grip strength were found in those with low preoperative MNA scores ( p < .05).

Conclusion:

After cardiac surgery, postdischarge weight loss occurs during a continued inflammatory response accompanied by decreased physical functioning and may not be a positive outcome. The impacts of weight loss, functional impairment, and inflammation during recovery on disability and frailty warrant further study.

Preoperative prediction of acute kidney injury--from clinical scores to biomarkers

Early acute kidney injury (AKI) diagnosis in critically ill children has been an important recent research focus because of the known association of AKI with poor outcomes and the requirement of early intervention to mitigate negative effects of AKI. In children having surgery, the preoperative period offers a unique opportunity to predict postoperative acute kidney injury (AKI), well before AKI occurs. Pediatric AKI epidemiologic studies have begun to identify which preoperative factors may predict development of postoperative cardiac surgery. Using these clinical risk factors, it may be possible to derive preoperative clinical risk scores and improve upon our ability to risk-stratify children into AKI treatment trials, pre-emptively provide conservative renal injury prevention strategies, and ultimately improve patient outcomes. Developing risk scores requires rigorous methodology and validation before widespread use. There is little information currently on the use of preoperative biological or physiological biomarkers to predict postoperative AKI, representing an important area of future research. This review will provide an overview of methodology of preoperative risk score development, discuss pediatric-specific issues around deriving such risk scores, including the combination of preoperative clinical and biologic biomarkers for AKI prediction, and suggest future research avenues.

Serum C-reactive protein as a possible marker to predict delayed hemorrhage after colonoscopic polypectomy

BACKGROUND

Post-polypectomy hemorrhage is one of the complications of colonscopic polypectomy. And there is no definitive and convenient laboratory test that could be used to predict risk of delayed post-polypectomy hemorrhage. This research aimed to study risk prediction of delayed post-polypectomy hemorrhage using serum C-reactive protein (CRP) level as a marker.

MATERIAL/METHODS

In a retrospective, case-controlled study, 302 cases of post-polypectomy patients were divided into hemorrhage group and non-hemorrhage group. The CRP levels 24-hours after colonscopic treatment were compared between the two groups to assess whether elevated serum CRP levels in addition to other risk factors such as age, gender, smoking, alcohol consumption, hypertension (AHT) and size of polyps may predict risk of delayed post-polypectomy hemorrhage.

RESULTS

The hemorrhage group had significantly higher levels of serum CRP (32.50±17.34 mg/L vs. 6. 32±6.02 mg/dL) and were also having a higher incidence of hypertension compared to the non- hemorrhage group (both P<0.05). Patients with elevated serum CRP levels (≥10 mg/L) after colonscopic treatment are at a higher risk of developing post-polypectomy hemorrhage (OR 1.329, 95%CI 1.125-1.571) as compared with patients whose CRP levels were not increased.

CONCLUSIONS

A higher level of serum CRP may serve as an indicator of delayed post-polypectomy hemorrhage and there appears to be a direct relationship between the serum CRP levels and the risk of post-polypectomy hemorrhage: the higher CRP levels the higher the risk of post-polypectomy hemorrhage.

High-sensitive C-reactive protein predicts outcome after coronary artery bypass

Background: Elevated high-sensitive C-reactive protein is a powerful independent predictor of cardiovascular events. However, there are scant data on its impact on midterm or long-term outcomes of coronary artery bypass grafting.

Method: We analyzed data of 2863 patients who underwent coronary artery bypass in 2006–2007. Early endpoints were hospital mortality and major morbidity. Midterm endpoints were overall mortality, major adverse cardiovascular events, and heart failure.

Results: During hospital stay, 26 patients died and 288 suffered major morbidity. After 3.6 years of follow-up, 56 patients had died, 105 had major adverse cardiovascular events, and 70 developed heart failure. Multivariate analysis revealed every 1 mg·L−1 increase of high-sensitive C-reactive protein was associated with increased odds ratio for early mortality (odds ratio = 2.50, p = 0.002), major morbidity (odds ratio = 1.38, p = 0.02), and hazard ratio for midterm mortality (hazard ratio = 1.68, p = 0.03), major adverse cardiovascular events (hazard ratio = 1.48, p = 0.04), and heart failure (hazard ratio = 1.88, p = 0.01). Preoperative high-sensitive C-reactive protein > 2.5 mg·L−1 predicted higher risks of early (hazard ratio = 2.69, p = 0.02) and midterm mortality (hazard ratio = 1.92, p = 0.02), major morbidity (hazard ratio = 1.46, p = 0.004), major adverse cardiovascular events (hazard ratio = 2.06, p < 0.001), and heart failure (hazard ratio = 1.71, p = 0.03).

Conclusions: Elevated high-sensitive C-reactive protein (>2.5 mg·L−1) predicts poor early and midterm outcomes after coronary artery bypass.

Increased preoperative C-reactive protein levels are associated with inhospital death after coronary artery bypass surgery

Increased C-reactive protein (CRP) is a predictor of cardiovascular risk, but its influence on outcomes after coronary artery bypass grafting surgery (CABG) is still incompletely studied. We studied the association between preoperative CRP and inhospital death after CABG. Patients with acute or chronic infectious or inflammatory disorders, autoimmune diseases, cancer, and prior cardiac surgery were excluded. Seventy-six patients were studied [27.6% with elevated CRP (>3 mg/l)]. Elevated CRP was more frequently found in patients who died than in those who survived (83.3% vs 17.1%, p = 0.003); mean CRP levels were, respectively, 6.5 ± 3.4 vs 2.4 ± 3.5 mg/l (p = 0.03). The hazard ratio of death was 11.7 for elevated CRP, and the ROC curve for the discrimination of death with CRP had an area under the curve of 0.82. An improvement to mortality risk prediction following CABG may be offered by the preoperative analysis of CRP.

Long term results of ST-segment elevation myocardial infarction versus non-ST-segment elevation myocardial infarction after off-pump coronary artery bypass grafting: propensity score matching analysis

There is no consensus as to which acute myocardial infarction subtype poses a greater risk after coronary artery bypass grafting (CABG). We compared the early and the long term results of off-pump coronary artery bypass grafting (OPCAB) between patients with STEMI (group I, n = 83), and NSTEMI (group II, n = 237). Group I had higher EuroSCORE, prevalence of emergency surgery, preoperative intra-aortic balloon pump use, preoperative emergency percutaneous transluminal coronary angioplasty, and preoperative thrombolytic use than group II. There were no significant differences in 30-day mortality and major adverse cardiac and cerebrovascular event (MACCE) between groups. Overall 8-yr survival was 93% and 87% in groups I and II, respectively. Freedom from MACCE after 8 yr was 92% and 93% in groups I and II, respectively. After propensity score matching analysis, there were no significant differences in preoperative parameters, postoperative in-hospital outcomes, and long-term clinical outcomes. Surgical results of OPCAB in patients with acute myocardial infarction show good results in terms of long-term survival and freedom from MACCE, with no significant differences in clinical outcomes between STEMI and NSTEMI groups.

Renal dysfunction and fluid and electrolyte disturbances

PURPOSE OF REVIEW

To examine recent developments in preventing and treating postoperative acute renal dysfunction. To review contemporary issues concerning perioperative fluid and electrolyte management.

RECENT FINDINGS

Renal dysfunction remains a major postoperative morbidity despite the advent of intermittent and continuous renal replacement therapies. It is also associated with increased mortality. Newer techniques, such as off-pump coronary artery bypass surgery, which promised to reduce the incidence of postoperative renal injury, have failed to do so. In addition, newer techniques such as endovascular repair of aortic disorder and the transcutaneous insertion of aortic valves are associated with substantial degrees of kidney injury partially due to the use of much intravenous contrast material. Therefore, the present-day approach to preventing contrast-induced nephropathy is reviewed. Electrolyte disturbances are especially problematic after certain types of surgery, such as trans-sphenoidal adenomectomy and surgeries requiring the use of large volumes of irrigating solutions.

SUMMARY

Renal dysfunction, along with fluid and electrolyte disturbances, is a major issue that needs to be considered as part of perioperative management. Moreover, it is the prevention of clinically significant renal injury and electrolyte disturbances that is the cornerstone of contemporary anesthetic and surgical care.

Preoperative C-reactive protein and atrial fibrillation after off-pump coronary bypass surgery

OBJECTIVE

The purpose of the present study was to investigate the association between preoperative C-reactive protein (CRP) and atrial fibrillation (AF) after isolated off-pump coronary bypass surgery.

METHODS

Of 683 consecutive patients undergoing isolated coronary bypass surgery by a single surgeon between January 2002 and March 2009, 552 were retrospectively analyzed after excluding the following 131 cases: on-pump surgery (n = 6), chronic AF (n = 14), pacemaker rhythm (n = 7), and preoperative CRP of ≥ 10 mg l(-1) (n = 104). We analyzed the correlation on a continuous basis per 1 SD increase in the logarithmically transformed value of CRP and on a group basis CRP level categorized into three groups: <1.0 mg l(-1), n = 196; 1.0-3.0 mg l(-1), n = 220; and 3.0-10.0 mg l(-1), n = 136.

RESULTS

AF occurred in 121 patients (21.9%, 121/552) of patients after surgery. The median value (interquartile range) of preoperative CRP (mg l(-1)) was significantly higher in patients who developed AF than in those who did not (2.2 (1.0-4.2) vs 1.3 (0.6-2.5), p = 0.001). The rate of 7-day survival free from AF was 65.4% in patients with CRP of 3.0-10.0 mg l(-1), 79.9% in those with CRP of 1.0-3.0 mg l(-1), and 85.7% in those with CRP of <1.0 mg l(-1) (log-rank test: p = 0.001). The unadjusted hazard ratio (95% confidence interval) for the association between CRP and postoperative AF was 1.65 (1.32-2.06) per 1 SD increase and 3.17 (1.86-5.40) for patients with CRP of 3.0-10.0 mg l(-1) versus those with levels of <1.0 mg l(-1). This association persisted after adjustment for the univariate predictors (1.43 (1.22-1.97) per 1 SD increase; 2.88 (1.67-4.97) for patients with CRP of 3.0-10.0 mg l(-1) vs <1.0 mg l(-1)) or the known risk factors (1.34 (1.18-1.86) per 1 SD increase; 2.52 (1.54-4.36) for patients with CRP of 3.0-10.0 mg l(-1) vs <1.0 mg l(-1)). The area under the receiver operating characteristic curve (95% confidence interval) for preoperative CRP as a predictor of postoperative AF was 0.68 (0.62-0.74) (p = 0.001).

CONCLUSIONS

Preoperative CRP is independently associated with the occurrence of AF after isolated off-pump coronary bypass surgery.

Association of serum procalcitonin with cardiovascular prognosis in coronary artery disease

BACKGROUND

Procalcitonin (PCT) is an established biomarker for the diagnosis of sepsis. Evidence is growing that PCT concentration correlates with the extent of atherosclerosis and prognosis in patients with coronary artery disease (CAD).

METHODS AND RESULTS

A total of 2,131 patients with CAD were followed up for a median of 3.6 years. During follow-up, death from cardiovascular causes was registered in 95 patients and non-fatal myocardial infarction in 85 patients. Median and quartile 1 and 3 are reported for PCT concentration. Patients who died of cardiovascular causes had higher PCT concentrations [0.021 (0.012/0.036) ng/ml vs. 0.015 (0.010/0.023) ng/ml; P<0.0001]. Patients with acute coronary syndrome had increased concentrations of PCT in relation to patients with stable angina [0.016 (0.011/0.027) ng/ml vs. 0.014 (0.009/0.014) ng/ml; P for trend <0.0001]. PCT concentration across quartiles was associated with the event rate (P=0.026; log-rank test) and mortality (P=0.00018). On Cox regression analysis, elevated PCT concentration was related to cardiovascular mortality [hazard ratio (HR), 1.34; 95% confidence interval (CI): 1.08-1.65, P=0.0070], but not to cardiovascular events (HR, 1.09; 95%CI: 0.93-1.28, P=0.28). After adjustment for C-reactive protein (CRP), PCT did not provide additional prognostic information.

CONCLUSIONS

PCT is associated with future cardiovascular mortality in patients with CAD, but PCT is not superior to CRP for prediction of outcome.

[Cardiac biomarkers in perioperative risk stratification]

OBJECTIVES

The field of new cardiac biomarkers has triggered physicians' enthusiasm because of their potential diagnostic and prognostic values for routine clinical practice in the surgical setting. The objective of the present article is to review the role of new cardiac biomarkers and their potential additive clinical value in predicting short- and long-term risk following cardiac and non-cardiac surgery.

DATA SOURCES

A PubMed(®) database research in English and French languages published until June 2010. Keywords were cardiac biomarkers, troponins, cardiac troponin I (cTnI), natriuretic peptides, B-type natriuretic peptide (BNP), C-reactive protein (CRP), multiple markers approach, risk stratification, clinical risk scores.

DATA SYNTHESIS

Numerous publications deal with the diagnostic and prognostic values of new cardiac biomarkers in cardiac and non-cardiac surgical settings and provide an increasing evidence of their interest, validating different hierarchical steps which are mandatory before recommending a wide use of biomarkers for routine practice. Even if the first studies demonstrating an additional prognostic value of serum postoperative cTnI and/or preoperative BNP when compared with clinical predictive models are now available, we still lack data concerning an actual positive impact of new biomarkers measurements on clinical decision making or practice, as well as patient care and outcome.

CONCLUSIONS

While use of new cardiac biomarkers in the perioperative period appears to be a simple and objective tool for risk stratification at the bedside, we still need to remain cautious concerning their additional clinical value on existing predictive models for routine practice.