Zinc-aspirin preconditioning reduces endothelial damage of arterial grafts in a rodent model of revascularization

Introduction

Coronary artery bypass grafting (CABG) is the most common cardiac surgical procedure. The prognosis of revascularization via CABG is determined by the patency of the used grafts, for which an intact endothelium is essential. The degree of ischemia-reperfusion injury (IRI), which occurs during the harvest and implantation of the grafts, is an important determinant of graft patency. Preconditioning with aspirin, a nonsteroidal anti-inflammatory drug has been shown to reduce the functional and molecular damage of arterial grafts in a rodent model. Studies have found that the zinc-aspirin complex may be able to exert an even better protective effect in pathological cardiovascular conditions. Thus, our aim was to characterize the protective effect of zinc-aspirin complex on free arterial grafts in a rodent model of revascularization.

Methods

Donor Lewis rats were treated with either zinc-aspirin, aspirin, or placebo (n = 8) for 5 days, then the aortic arches were harvested and stored in cold preservation solution and implanted heterotopically in the abdominal cavity of the recipient rats, followed by 2 h of reperfusion. There was also a non-ischemia-reperfusion control group (n = 8). Functional measurements using organ bath and histomorphological changes using immunohistochemistry were analyzed.

Results

The endothelium dependent maximal vasorelaxation was improved (non-transplanted control group: 82% ± 3%, transplanted control group: 14% ± 2%, aspirin group: 31% ± 4%, zinc-aspirin group: 52% ± 4%), the nitro-oxidative stress and cell apoptosis decreased, and significant endothelial protection was shown in the groups preconditioned with aspirin or zinc-aspirin. However, zinc-aspirin proved to be more effective in the reduction of IRI, than aspirin alone.

Discussion

Preconditioning with zinc-aspirin could be a promising way to protect the function and structural integrity of free arterial grafts, thus improving the outcomes of CABG.

Preoperative continuation of aspirin before isolated heart valve surgery and postoperative bleeding and transfusion: a single-center retrospective study

BACKGROUND

The risks and benefits of preoperative aspirin continuation in patients undergoing isolated heart valve replacement surgery are unclear. We investigated the effect of aspirin continuation on the risk of bleeding and transfusion in these patients.

METHODS

In this single center, retrospective study, among 474 adult patients who underwent isolated heart valve surgery between April 2013 and June 2018, 269 continued aspirin within 5 days before surgery (aspirin group) and 205 patients did not take or stopped aspirin no later than 5 days before surgery (non-aspirin group). The chi-square test, the Mann-Whitney U-test, and the Student's T-test were used to compare data between the groups. Univariate and Multivariate logistic regressions were used to assess crude and adjusted relationships between outcome and exposure.

RESULTS

The primary outcome, red blood cell (RBC) transfusion, occurred in 59 patients (22%) of the aspirin group and in 24 patients (12%) of the non-aspirin group (p = 0.004). After adjustment for confounding factors, continuation of aspirin was no longer associated with RBC transfusion (aOR1.8;95%CI,0.98-3.2;p = 0.06). The amount of allogenic blood products, the incidence of surgical re-exploration for bleeding, the volume of re-transfused cell-saved blood, and the cumulative chest tube drainage during the first 24 postoperative hours were similar between groups.

CONCLUSION

Preoperative continuation of aspirin in patients undergoing isolated heart valve surgery is neither associated with a higher incidence of RBC transfusion, nor with larger perioperative blood loss, or more frequent surgical revision for bleeding.

TRIAL REGISTRATION

Clinicaltrials.gov (NCT05151796).

Aspirin intervention before ICU admission reduced the mortality in critically ill patients with acute kidney injury: results from the MIMIC-IV

Background: Aspirin, with its pleiotropic effects such as anti-inflammatory and anti-platelet aggregation, has been widely used for anti-inflammatory, analgesic, and cardiovascular diseases. However, the association between the use of aspirin before the intensive care unit (ICU) and clinical outcomes in critically ill patients with acute kidney injury (AKI) is unknown. Methods: Patients with AKI in this retrospective observational study were selected from the Marketplace for Medical Information in Intensive Care IV (MIMIC-IV). The association between aspirin intervention and 30-day mortality was assessed using Cox proportional hazards model. Logistic regression models were used to assess the association of aspirin intervention with the risks of intracranial hemorrhage, gastrointestinal bleeding and blood transfusion. The propensity score matching (PSM) method was adopted to balance the baseline variables. Sensitivity analysis was performed to validate the results by multiple interpolations for the missing data. Results: The study included 4237 pre-ICU aspirin users and 9745 non-users. In multivariate models, we found a decreased risk of mortality in those who received aspirin before ICU compared to those who did not (30-day:hazard ratio [HR], 0.70; 95% CI, 0.62-0.79; p < 0.001; 90-day:HR, 0.70; 95% CI, 0.63-0.77, p < 0.001; 180-day:HR, 0.72; 95%CI,0.65-0.79, p < 0.001). This benefit was consistent in the post-PSM analyses, sensitivity analyses, and subgroup analyses. Moreover, aspirin intervention was associated with a reduced risk of intracranial hemorrhage and gastrointestinal bleeding (HR, 0.16; 95% CI, 0.10-0.25; p < 0.001; HR, 0.59; 95% CI, 0.38-0.88, p = 0.012) after being adjusted by relating covariates, whereas with a increased risk of blood transfusion (HR, 1.28; 95% CI, 1.16-1.46; p < 0.001). Conclusion: Patients with AKI treated with aspirin before ICU admission might have reduced 30-day, 90-day and 180-day mortality without increasing the risk of intracranial hemorrhage (ICH) or gastrointestinal bleeding, but may increase the risk of transfusion.

Albumin Infusion and Blood Loss After Cardiac Surgery

BACKGROUND

In the recent ALBICS (ALBumin In Cardiac Surgery) trial, 4% albumin used for cardiopulmonary bypass priming and volume replacement increased perioperative bleeding compared with Ringer acetate. In the present exploratory study, albumin-related bleeding was further characterized.

METHODS

Ringer acetate and 4% albumin were compared in a randomized, double-blinded fashion in 1386 on-pump adult cardiac surgery patients. The study end points for bleeding were the Universal Definition of Perioperative Bleeding (UDPB) class and its components.

RESULTS

The UDPB bleeding grades were higher in the albumin group than the Ringer group: "insignificant" (albumin vs Ringer: 47.5% vs 62.9%), "mild" (12.7% vs 8.9%), "moderate" (28.7% vs 24.4%), "severe" (10.2% vs 3.2%), and "massive" (0.9% vs. 0.6%; P < .001). Patients in the albumin group received red blood cells (45.2% vs 31.5%; odds ratio [OR], 1.80; 95% CI, 1.44-2.24; P < .001), platelets (33.3% vs 21.8%; OR, 1.79; 95% CI, 1.41-2.28; P < .001), and fibrinogen (5.6% vs 2.6%; OR, 2.24; 95% CI, 1.27-3.95; P < .05), and underwent resternotomy (5.3% vs 1.9%; OR, 2.95; 95% CI, 1.55-5.60, P < .001) more often than patients in the Ringer group. The strongest predictors of bleeding were albumin group allocation (OR, 2.18; 95% CI, 1.74-2.74) and complex (OR, 2.61; 95% CI, 2.02-3.37) and urgent surgery (OR, 1.63; 95% CI, 1.26-2.13). In interaction analysis, the effect of albumin on the risk of bleeding was stronger in patients on preoperative acetylsalicylic acid.

CONCLUSIONS

Perioperative administration of albumin, compared with Ringer's acetate, resulted in increased blood loss and higher UDBP class. The magnitude of this effect was similar to the complexity and urgency of the surgery.

Association Between Proton Pump Inhibitor Exposure and Acute Kidney Injury After Cardiac Surgery

OBJECTIVE

To evaluate the association of preoperative proton pump inhibitor (PPI) exposure with incident acute kidney injury (AKI) after cardiac surgery.

PATIENTS AND METHODS

The Severance cardiac surgery cohort included 9860 cardiac surgery patients aged 18 years or older. The National Health Insurance Service-senior cohort included 2933 patients aged 60 years or older who underwent cardiac surgery. Preoperative PPI exposure was defined as a PPI prescription within 3 weeks prior to cardiac surgery. Primary outcomes were postoperative AKI and AKI requiring dialysis (AKI-dialysis).

RESULTS

In the Severance cardiac surgery cohort after propensity score matching for PPI exposure, incident AKI (44.0% [472 of 1073] vs 40.5% [1304 of 3219]) and AKI-dialysis (5.8% [62 of 1073] vs 3.7% [119 of 3219]) were more common in patients exposed to PPI than in those who were not. Hospital and intensive care unit stay durations were longer among PPI-exposed than PPI-nonexposed patients. Multivariable conditional logistic analyses revealed that PPI exposure was significantly associated with incident AKI (adjusted odds ratio [AOR], 1.21; 95% CI, 1.03 to 1.42; P=.02) and AKI-dialysis (AOR, 1.74; 95% CI, 1.15 to 2.63; P=.009). The National Health Insurance Service-Senior cohort had similar results, revealing a significant association between PPI exposure and incident AKI-dialysis (AOR, 1.87; 95% CI, 1.25 to 2.81; P=.003). Discontinuation of PPI prior to operation was associated with a lower odds of AKI development in both cohorts.

CONCLUSION

Preoperative PPI exposure may be a modifiable risk factor for AKI among patients undergoing cardiac surgery.

Coagulation and Transfusion Updates From 2021

2021 and the COVID 19 pandemic have brought unprecedented blood shortages worldwide. These deficits have propelled national efforts to reduce blood usage, including limiting elective services and accelerating Patient Blood Management (PBM) initiatives. A host of research dedicated to blood usage and management within cardiac surgery has continued to emerge. The intent of this review is to highlight this past year's research pertaining to PBM and COVID-19-related coagulation changes.

Analysis of prognostic factors for in-hospital mortality in patients with unplanned re-exploration after cardiovascular surgery

Objective

To explore the prognostic factors for in-hospital mortality in patients with unplanned re-exploration after cardiovascular surgery.

Methods

We retrospectively analyzed the data of 100 patients who underwent unplanned re-exploration after cardiovascular surgery in our hospital between May 2010 and May 2020. There were 77 males and 23 females, aged (55.1 ± 15.2) years. Demographic characteristics, surgical information, perioperative complications were collected to establish a database. These patients were divided into surviving and non-surviving groups according to in-hospital mortality. Logistic regression was used for multivariable analysis to explore the prognostic factors of in-hospital mortality. These statistically significant indicators were selected for drawing the receiver operating characteristic curve of the evaluation model, calculating the area under the curve (AUC) and evaluating the effectiveness of the new model with Hosmer–Lemeshow C-statistic.

Results

In-hospital mortality in patients with unplanned re-exploration after cardiovascular surgery was 26.0% (26/100). Multivariate logistics regression revealed that the operation time of unplanned re-exploration, the worst blood creatinine value within 48 h before the re-exploration, the worst lactate value within 24 h after the re-exploration, cardiac insufficiency, respiratory insufficiency, and acute kidney injury were independent prognostic factors (P < 0.05). The AUC of the new assessment model constituted by these prognostic factors was 0.910, and the Hosmer–Lemeshow C-statistic was 4.153 (P = 0.762).

Conclusions

Operation time of unplanned re-exploration, worst serum creatinine value within 48 h before re-exploration, worst lactate value within 24 h after re-exploration, cardiac insufficiency, respiratory insufficiency, and acute kidney injury are the main prognostic factors for in-hospital mortality in patients with unplanned re-exploration after cardiovascular surgery. Identifying these prognostic factors can effectively facilitate preventive measures and improve patient outcomes.

Perioperative Guidelines on Antiplatelet and Anticoagulant Agents: 2022 Update

Purpose of Review

Multiple guidelines and recommendations have been written to address the perioperative management of antiplatelet and anticoagulant drugs. In this review, we evaluated the recent guidelines in non-cardiac, cardiac, and regional anesthesia. Furthermore, we focused on unresolved problems and novel approaches for optimized perioperative management.

Recent Findings

Vitamin K antagonists should be stopped 3 to 5 days before surgery. Preoperative laboratory testing is recommended. Bridging therapy does not decrease the perioperative thromboembolic risk and might increase perioperative bleeding risk. In patients on direct-acting oral anticoagulants (DOAC), a discontinuation interval of 24 and 48 h in those scheduled for surgery with low and high bleeding risk, respectively, has been shown to be saved. Several guidelines for regional anesthesia recommend a conservative interruption interval of 72 h for DOACs before neuraxial anesthesia. Finally, aspirin is commonly continued in the perioperative period, whereas potent P2Y12 receptor inhibitors should be stopped, drug-specifically, 3 to 7 days before surgery.

Summary

Many guidelines have been published from various societies. Their applicability is limited in emergent or urgent surgery, where novel approaches might be helpful. However, their evidence is commonly based on small series, case reports, or expert opinions.

Aspirin Reduces Ischemia-Reperfusion Injury Induced Endothelial Cell Damage of Arterial Grafts in a Rodent Model

Long-term graft patency determines the prognosis of revascularization after coronary artery bypass grafting (CABG). Ischemia-reperfusion (I/R) injury of the graft suffered during harvesting and after implantation might influence graft patency. Aspirin, a nonsteroidal anti-inflammatory drug improves the long-term patency of vein grafts. Whether aspirin has the same effect on arterial grafts is questionable. We aimed to characterize the beneficial effects of aspirin on arterial bypass grafts in a rodent revascularization model. We gave Lewis rats oral pretreatment of either aspirin (n = 8) or saline (n = 8) for 5 days, then aortic arches were explanted and stored in cold preservation solution. The third group (n = 8) was a non-ischemia-reperfusion control. Afterwards the aortic arches were implanted into the abdominal aorta of recipient rats followed by 2 h of reperfusion. Endothelium-dependent vasorelaxation was examined with organ bath experiments. Immunohistochemical staining were carried out. Endothelium-dependent maximal vasorelaxation improved, nitro-oxidative stress and cell apoptosis decreased, and significant endothelial protection was shown in the aspirin preconditioned group, compared to the transplanted control group. Significantly improved endothelial function and reduced I/R injury induced structural damage were observed in free arterial grafts after oral administration of aspirin. Aspirin preconditioning before elective CABG might be beneficial on free arterial graft patency.

Impact of preoperative antithrombotic therapy in patients undergoing elective isolated coronary artery bypass grafting

OBJECTIVES

The objective of this retrospective study was to assess differences in clinical outcomes between patients on acetylsalicylic acid (ASA) monotherapy and patients on other antithrombotic (AT) regimens undergoing elective coronary artery bypass grafting (CABG).

METHODS

Patients who underwent elective isolated CABG between 2017 and 2019 at the Catharina Hospital Eindhoven were eligible for this study. The primary end points were re-exploration for bleeding and postoperative blood product transfusion. Secondary end points included 30-day mortality, in-hospital stroke, in-hospital myocardial infarction and duration of hospitalization. Propensity matching was used to compare outcomes of the main study groups (ASA vs other AT therapy) and subgroups of AT therapy (guideline adherence vs non-adherence).

RESULTS

A total of 1068 patients were included: 710 patients on ASA monotherapy and 358 patients on other AT regimens. In the 256 matched patients in the main study groups, using AT regimens other than ASA monotherapy was associated with increased risk of re-exploration for bleeding [6.6% vs 2.0%, P = 0.017; odds ratio (OR) 3.57 (1.29-9.83)] and increased use of blood products [37.5% vs 20.3%, P < 0.001; OR 2.35 (1.58-3.49)]. In 122 matched subgroup patients, non-adherence was associated with an increased risk of re-exploration [10.7% vs 3.3%, P = 0.044; OR 3.52 (1.11-11.12)] and increased blood product use [51.6% vs 25.4%, P < 0.001; OR 3.13 (1.83-5.38)]. Secondary end points were not significantly different among the main study groups and subgroups.

CONCLUSIONS

Preoperative use of AT therapy other than ASA monotherapy in patients who elected CABG was associated with the increased postoperative use of blood products and risk of re-exploration for bleeding; this finding was even more pronounced in non-guideline-adherent patients.

Impact of Preoperative Aspirin on Long-Term Outcomes in Diabetic Patients Following Coronary Artery Bypass Grafting: a Propensity Score Matched Study

Introduction

This study aimed to determine the effect of preoperative aspirin administration on early and long-term clinical outcomes in patients suffering from diabetes mellitus (DM) undergoing coronary artery bypass grafting (CABG).

Methods

In this observational study, a total of 315 patients were included and grouped according to the time interval between their last aspirin dose and the time of surgery; patients who had been continued aspirin intake with last administered dose ≤ 24-hours before CABG (n=144) and those who had been given the last dose of aspirin between 24 to 48 hours before CABG (n=171).

Results

Multivariable analysis showed that the continuation of preoperative aspirin intake ≤ 24 hours before CABG in patients with DM is associated with reduced incidence of 30-day major adverse cardiac and cerebral events (MACCE) (P=0.004) as well as reduced incidence of composite 30-day mortality/MACCE (P=0.012). During mean follow-up of 37±17.5 months, the unadjusted hazard ratio (HR) showed that aspirin ≤ 24 hours prior CABG in patients with DM significantly reduced the incidence of MACCE and composite of mortality/MACCE during follow-up (HR: 0.50; 95% confidence interval [CI]: 0.29-0.87; P=0.014 and HR: 0.61; 95% CI: 0.38-0.97; P=0.039, respectively). However, after propensity score (PS) matching, the PS-adjusted HR showed a non-significant trend towards the reduction of MACCE during follow-up (HR: 0.58; 95% CI: 0.31-1.06; P=0.081).

Conclusion

Continuation of preoperative aspirin intake ≤ 24 hours before CABG in patients with DM is associated with reduced incidence of early MACCE, but without significant influence on long-term outcomes.

Preoperative Functional Platelet Number Is Inversely Associated With 30-Day Mortality After Cardiac Surgery: A Retrospective Cohort Study

Background. We hypothesize that preoperative functional platelet number (platelet count multiplied by platelet aggregation percentage) are associated with 30-day mortality after cardiac surgery. Methods. We linked our preoperative testing database with the STS (Society of Thoracic Surgeon) database to form a study cohort of 1390 patients who had cardiac surgeries between January 2008 and December 2013. Preoperative tests of platelet count and platelet aggregation were routinely performed on all cardiac surgical patients within 24 hours before entering the operating room. Multiple logistic regression models were used to determine whether functional platelet number are associated with 30-day mortality, modified composite major adverse cardiocerebral events, postoperative renal failure or requirement for new renal replacement therapy, and reoperation for bleeding. Log-linear models were used to examine whether functional platelet numbers are associated with hospital length of stay and intensive care unit length of stay. Results. Functional platelet number had an inverse association with 30-day mortality, and each 50 × 10⁹/L increase in functional platelet number resulted in decreased 30-day mortality (odds ratio of 0.767 with 95% confidence interval = 0.591-0.996). For secondary outcomes, functional platelet number was neither associated with major adverse cardiocerebral event nor length of stay. However, we found that each 50 × 10⁹/L increase in functional platelet number was associated with decreased reoperations for bleeding (odds ratio of 0.778 with 95% confidence interval = 0.636-0.951). Conclusions. The preoperative functional platelet number had significant associations with 30-day mortality after cardiac surgery. Functional platelet number could be used to guide timing of cardiac surgery, especially as more and more patients are receiving antiplatelet medications nowadays.

Point-of-Care Platelet Function Monitoring: Implications for Patients With Platelet Inhibitors in Cardiac Surgery

Although most physicians are comfortable managing the limited anticoagulant effect of aspirin, the recent administration of potent P2Y₁₂ receptor inhibitors in patients undergoing cardiac surgery remains a dilemma. Guidelines recommend discontinuation of potent P2Y₁₂ inhibitors 5- to- 7 days before surgery to reduce the risk of postoperative hemorrhage. Such a strategy might not be feasible before urgent surgery, due to ongoing myocardial ischemia or in patients at high risk for thromboembolic events. Recently, different point-of-care devices to assess functional platelet quality have become available for clinical use. The aim of this narrative review was to evaluate the implications and potential benefits of platelet function monitoring in guiding perioperative management and therapeutic options in patients treated with antiplatelets, including aspirin or P2Y₁₂ receptor inhibitors, undergoing cardiac surgery. No objective superiority of one point-of-care device over another was found in a large meta-analysis. Their accuracy and reliability are generally limited in the perioperative period. In particular, preoperative platelet function testing has been used to assess platelet contribution to bleeding after cardiac surgery. However, predictive values for postoperative hemorrhage and transfusion requirements are low, and there is a significant variability between and within these tests. Further, platelet function monitoring has been used to optimize the preoperative waiting period after cessation of dual antiplatelet therapy before urgent cardiac surgery. Furthermore, studies assessing their value in therapeutic decisions in bleeding patients after cardiac surgery are scarce. A general and liberal use of perioperative platelet function testing is not yet recommended.

Adjusted preoperative variables to predict perioperative red blood cell transfusion in coronary artery bypass grafting

BACKGROUND

The variables for predicting blood transfusion perioperatively are not completely clear in coronary artery bypass grafting (CABG) patients.

OBJECTIVES

To construct a comprehensive model to predict perioperative RBC transfusion in patients undergoing isolated CABG using adjusted preoperative variables.

METHODS

Perioperative data of 1253 patients who underwent isolated CABG by the same surgical team were collected from April 2018 to March 2019. Logistic regression analyses were used to establish equations to construct two models for predicting intraoperative and postoperative RBC transfusions, respectively. All significant variables included in the two models were combined to form a comprehensive model to predict perioperative RBC transfusion. Area under the receiver operating characteristic (ROC) curve (AUC) was used to evaluate the discriminatory power of the models.

RESULTS

The total RBC transfusion rate for CABG patients during hospitalization was 29.05%. The rate of intraoperative and postoperative RBC transfusions was 6.9% and 26.7%, respectively. Eight variables in a total of 30 risk factors constituted the intraoperative prediction model, 12 variables constituted the postoperative prediction model, and 13 variables for the combined model. The AUC of the three models were 0.87, 0.82, and 0.83, respectively, demonstrating moderate discriminatory power for RBC transfusion during the intraoperative, postoperative, and perioperative periods.

CONCLUSION

The comprehensive model combined with all variables of predicting intraoperative and postoperative RBC transfusion is feasible for predicting perioperative RBC transfusion.

Bleeding Management Practices of Australian Cardiac Surgeons, Anesthesiologists and Perfusionists: A Cross-Sectional National Survey Incorporating the Theoretical Domains Framework (TDF) and COM-B Model

Purpose

Excessive bleeding is an acknowledged consequence of cardiac surgery, occurring in up to 10% of adult patients. This clinically important complication leads to poorer patient outcomes. Clinical practice guidelines are available to support best practice however variability in bleeding management practice and related adverse outcomes still exist. This study had two objectives: 1) to gain insight into current bleeding management practice for adult cardiac surgery in Australia and how that compared to guidelines and literature; and 2) to understand perceived difficulties clinicians face implementing improvements in bleeding management.

Methods

A national cross-sectional questionnaire survey was utilized. Perspectives were sought from cardiac surgeons, cardiac anesthesiologists and perfusionists. Thirty-nine closed-ended questions focused on routine bleeding management practices to address pre and intra-operative care. One open-ended question was asked; “What would assist you to improve bleeding management with cardiac surgery patients?” Quantitative data were analysed with SPSS. Qualitative data were categorized into the domains of the Theoretical Domains Framework; the domains were then mapped to the COM-B model.

Results

Survey responses from 159 Anesthesiologists, 39 cardiac surgeons and 86 perfusionists were included (response rate 37%). Four of the recommendations queried in this survey were reported as routinely adhered to < 50% of the time, 9 queried recommendations were adhered to 51–75% of the time and 4 recommendations were routinely followed >76% of the time.

Conclusion

There is a wide variation in peri-operative bleeding management practice among cardiac anaesthesiologists, surgeons and perfusionists in Australian cardiac surgery units. Conceptualizing factors believed necessary to improve practice with the TDF and COM-B model found that bleeding management could be improved with a standardized approach including; point of care diagnostic assays, a bleeding management algorithm, access to concentrated coagulation factors, cardiac surgery specific bleeding management education, multidisciplinary team agreement and support, and an overarching national approach.

Association between preoperative aspirin and acute kidney injury following coronary artery bypass grafting

OBJECTIVE

To test the hypothesis that preoperative aspirin administered within 24 hours before coronary artery bypass grafting (CABG) could reduce the incidence of postoperative acute kidney injury (AKI) following CABG.

METHODS

In this retrospective study, 696 patients were assigned to groups according to the time interval between their last aspirin dose administration and the time of surgery. A total of 322 patients received aspirin ≤24 hours before CABG, and 374 patients received aspirin between 24 and 48 hours before CABG. The primary outcome was postoperative AKI of any stage as defined by the Kidney Disease Improving Global Outcomes criteria. Propensity score matching selected 274 pairs for the final comparison.

RESULTS

Multivariable analysis showed that administration of aspirin within 24 hours of CABG was independently associated with reduction of AKI incidence by 36% (odds ratio, 0.64; 95% confidence interval, 0.45-0.91; P = .014). It was also noted that patients receiving their last aspirin dose ≤24 hours before CABG had a significantly higher glomerular filtration rate at discharge compared with patients who received aspirin between 24 and 48 hours before CABG. Propensity score matching analysis showed that patients receiving aspirin within 24 hours before CABG had a lower incidence of AKI compared with patients who discontinued aspirin between 24 and 48 hours before CABG (25.1% vs 36.8%; P = .004).

CONCLUSIONS

Continuation of aspirin until the day of surgery, with the last aspirin dose administered ≤24 hours before CABG, is associated with a significant reduction of postoperative AKI.

Pre-operative use of aspirin in patients undergoing coronary artery bypass grafting: a systematic review and updated meta-analysis

Background

Aspirin therapy improves saphenous vein graft (SVG) patency in patients undergoing coronary artery bypass graft (CABG), however, its use in the pre-operative period remains controversial. Therefore, we conducted a systematic review and meta-analysis of randomized-controlled trials (RCTs) to update the evidence about risk and benefits of pre-operative aspirin therapy in patients undergoing CABG.

Methods

Electronic databases (Medline, Embase, PubMed, Cochrane Library, and Scopus) were searched to identify RCTs evaluating the effect of aspirin versus placebo/control before CABG. Two investigators independently and in duplicate screened citations and extracted data and rated the risk of bias. The strength of evidence was appraised using the Grading of Recommendation Assessment, Development, and Evaluation (GRADE) approach. Meta-analysis was performed using a random-effects model. The main outcomes of interest were 30-day mortality, peri-operative myocardial infarction (MI), chest tube drainage and SVG occlusion.

Results

A total of 13 RCTs involving 4,377 participants (2,266/2,111 pre-operative aspirin/control) met the inclusion criteria. Pre-operative aspirin reduced the risk of SVG occlusion [risk ratio (RR): 0.69, 95% confidence interval (CI): 0.49-0.97, P=0.03, I²=16%], but no differences in mortality (RR: 1.41, 95% Cl: 0.73-2.74, I²=0%) and MI (RR: 0.84, 95% CI: 0.69-1.03, I²=0%) were found. However, pre-operative aspirin increased chest tube drainage (MD: 100.40 mL, 95% CI: 24.32-176.47 mL, P=0.01, I²=84%) and surgical re-exploration (RR: 1.52, 95% CI: 1.02-2.27, P=0.04, I²=8%), with no significant difference in RBC transfusion (RR: 1.06, 95% CI: 0.90-1.25, I²=35%).

Conclusions

Based on trials where the rated body of evidence was of low to very-low quality, pre-operative aspirin improves SVG patency but increases chest tube drainage and need for surgical re-exploration.