Inflammatory Biomarkers and Blood Physical Property Transformations Following On-Pump Coronary Artery Bypass Graft Surgery

OBJECTIVE

This study aimed to compare the hemorheological and inflammatory changes before and after coronary artery bypass graft (CABG) surgery, as factors such as hypothermia, hemodilution, transfusion, and other variables affect blood viscosity and inflammation during the procedure.

METHODS

A total of 25 patients who underwent CABG surgery were enrolled in this study. Whole blood was collected just before the CABG (D0), 2 days after surgery (D2), and 5 days after surgery (D5). The plasma viscosity (PV) and whole blood viscosity (WBV) were measured at shear rates ranging from 0.1 to 1000 s-1 using a rheometer, and the mean values were compared. Inflammatory markers were also assessed and analyzed in relation to the hemorheological changes.

RESULTS

Compared with the baseline values, the PV significantly increased after 5 days. WBV showed a significant increase on day 2 and after 5 days. The WBV and fibrinogen were significantly correlated on day 2 and day 5 but not before surgery. Inflammatory markers such as CRP, WBC, platelets, and fibrinogen also demonstrated notable changes in relation to the hemorheological alterations.

CONCLUSIONS

This study highlights the crucial finding that hyperviscosity, characterized by elevated PV and WBV, persists for almost one week after on-pump CABG surgery. Understanding the interplay between inflammation and hemorheological properties during the postoperative period is crucial for optimizing patient care. Future research should focus on exploring the underlying mechanisms and potential therapeutic interventions to mitigate the impact of inflammation on blood viscosity and improve patient outcomes following CABG surgery.

Is Preoperative Adrenal Insufficiency Screening Necessary for Cardiovascular Thoracic Surgery Patients?

Background: The association between adrenal insufficiency (AI) and the treatment outcomes of cardiothoracic surgery patients has been little reported. The aims of this study were to investigate the incidence of AI and to compare the post-surgical outcomes of patients with perioperatively treated AI and patients with a normal adrenal response. Methods: A 1.5-year prospective study was conducted in 98 patients scheduled for cardiothoracic surgery. Patients were categorized as either AI or normal-adrenal-response patients. Those with AI were treated with stress doses of glucocorticoid perioperatively. The post-surgical outcomes of patients with AI and of those with a normal adrenaline response were analyzed using multivariable analysis. Results: The overall incidence of AI was 34.7%. There were no statistically significant differences in post-surgical outcomes, including prolonged hospital stay, postoperative infection, prolonged inotropic drug use and relative AI, between the two groups. Only the rate of hyperglycemia requiring insulin infusion was significantly higher in the AI group than in the non-AI group (OR = 14.15, 95% CI = 1.44-138.60, p = 0.02). Conclusions: The proper diagnosis and management of AI can result in surgical outcomes in AI patients comparable to those of normal-adrenal-response patients. Non-life-threatening hyperglycemia requiring insulin infusion was found only in the AI group.

Guidelines for enhanced recovery after cardiac surgery. Consensus document of Spanish Societies of Anesthesia (SEDAR), Cardiovascular Surgery (SECCE) and Perfusionists (AEP)

The ERAS guidelines are intended to identify, disseminate and promote the implementation of the best, scientific evidence-based actions to decrease variability in clinical practice. The implementation of these practices in the global clinical process will promote better outcomes and the shortening of hospital and critical care unit stays, thereby resulting in a reduction in costs and in greater efficiency. After completing a systematic review at each of the points of the perioperative process in cardiac surgery, recommendations have been developed based on the best scientific evidence currently available with the consensus of the scientific societies involved.

Effects of corticosteroids on new-onset atrial fibrillation after cardiac surgery: A meta-analysis of randomized controlled trials

BACKGROUND

Postoperative atrial fibrillation (POAF) occurs commonly after cardiac surgery. Studies suggest that corticosteroid can reduce the incident of POAF. However, the results remain controversial. This meta-analysis aimed to evaluate the efficacy and safety corticosteroid on the prevention of POAF following cardiac surgery.

METHODS

Randomized controlled trials were identified through a systematic literature search. Two investigators independently searched articles, extracted data, and assessed the quality of included studies. Primary outcome was the incidence of POAF as well as length of hospital stay and intensive care unit stay, wound and other infection, mortality, duration of ventilation, myocardial infarction, gastrointestinal complications, high blood sugar, stroke, and postoperative bleeding.

RESULTS

Fourteen studies with 13,803 patients were finally involved in the present study. Overall, corticosteroid significantly decreased the risk of POAF (relative risk [RR], 0.7; 95% confidence interval [CI], 0.55-0.89; P = .003). There were no significant differences in the incidence of length of intensive care unit stay (RR, -2.32; 95% CI, -5.44 to 0.80; P = .14) and hospital stay (RR, -0.43; 95% CI, -0.84 to -0.02; P = .04), infections (RR, 1.01; 95% CI, 0.83-1.23; P = .9), mortality (RR, 0.87; 95% CI, 0.71-1.06; P = .16), duration of ventilation (RR, -0.29; 95% CI, -0.65 to 0.07; P = .12), gastrointestinal complications (RR, 1.26; 95% CI, 0.91-1.76; P = .16), high blood sugar (RR, 1.98; 95% CI, 0.91-4.31; P = .09), stroke (RR, 0.9; 95% CI, 0.69-1.18; P = .45), postoperative bleeding (RR -44.54; 95% CI, -115.28 to 26.20; P = .22) and myocardial infarction (RR, 1.71; 95% CI, 0.96-1.43; P = .12).

CONCLUSION

Our review suggests that the efficacy of corticosteroid might be beneficial to POAF development in patients undergoing cardiac surgery. The strength of this association remains uncertain because of statistical and clinical heterogeneity among the included studies.

Acute adrenal cortex injury during cardiopulmonary bypass in a canine model

OBJECTIVE

Cardiopulmonary bypass (CPB) might induce systemic inflammatory responses that cause acute injuries to multiple organs. However, no direct evidence exists to determine whether CPB leads to adrenal cortex injury or to describe its underlying mechanism.

METHODS

Twelve healthy adult beagles were randomly assigned into control and CPB groups. After cannulation, mild hypothermia CPB was performed in the CPB group but not in the control group. The serum concentrations of various cytokines, cortisol, and aldosterone were assessed. Adrenal cortex injuries were evaluated using standard histological methods. Steroidogenic enzymes and the nucleotide-binding oligomerization domain-like receptor containing pyrin domain 3 (NLRP3) inflammasome pathway were detected using quantitative polymerase chain reaction and Western blot analysis.

RESULTS

During CPB, serum interleukin (IL)-6, IL-8, IL-10, tumor necrosis factor α, cortisol, and aldosterone levels were significantly higher in the CPB group. The pathologic study revealed higher injury scores (3.6 ± 0.6 vs 0.7 ± 0.7) and significantly more severe edema, inflammatory cell infiltration (lymphocytes and neutrophils), and apoptosis in the CPB group. The electron microscopic examination showed swollen mitochondria, ruptured mitochondrial cristae, reduced lipid droplets, and increased secondary lysosomes in the CPB group. The mRNA expression levels of NLRP3 and the protein levels of 17α-hydroxylase and IL-1β in adrenal tissue were significantly upregulated in the CPB group.

CONCLUSIONS

CPB induces significant systemic and local inflammation in the adrenal cortex and results in cytological architectural and ultrastructural alterations in adrenocorticocytes. In addition, the NLRP3 inflammasome pathway might promote adrenal gland injury during CPB and might represent a novel potential therapeutic target.

Hemolysis and Inflammatory Response to Extracorporeal Circulation during On-Pump CABG: Comparison between Roller and Centrifugal Pump Systems

Objective

To compare the perioperative incidence rates of hemolysis and inflammatory response in patients undergoing coronary artery bypass grafting with the two main types of cardiopulmonary bypass, centrifugal and roller pumps, and establish correlations among hemolytic and inflammatory changes.

Methods

This was a prospective, randomized trial of 60 patients assigned to either roller pump (G1, n=30) or centrifugal pump (G2, n=30) bypass. Markers of hemolysis (serum haptoglobin, lactate dehydrogenase [LDH]) and inflammation (interleukin [IL]1ß, IL-6, and TNF-α) were measured and analyzed.

Results

There was no significant between-group difference in the variables of interest. In G1, there was a positive association with IL-6 and TNF-α (P<0.01 and P<0.05, respectively). In G2, there was a positive association with LDH in the postoperative period (P<0.5). At 24h post-cardiopulmonary bypass, there were positive associations between LDH and IL-1ß (P<0.05), LDH and TNF-α (P<0.01), haptoglobin and TNF-α (P<0.05), and LDH and TNF-α (P<0.01) in G1, and between LDH and IL-6 (P<0.01), LDH and TNF-α (P<0.01), and LDH and IL-6 (P<0.01) in G2.

Conclusion

There were no significant between-group differences in markers of hemolysis or inflammation. IL-6 and TNF-α were positively associated with duration of cardiopulmonary bypass in G1, while LDH was positively associated with duration of cardiopulmonary bypass in G2. The rate of significant associations between markers of hemolysis and inflammation was higher in the roller pump group (G1).

Registration number

ReBEC (RBR-92b9dg).

Trends and Patterns of Corticosteroid Use During Coronary Artery Bypass Grafting Surgery in the United States

BACKGROUND

Several clinical trials have documented clinical benefits associated with prophylactic corticosteroid administration at the time of coronary artery bypass graft (CABG) surgery, including a reduction in the risk of atrial fibrillation and hospital length of stay. Despite the published data, the extent to which providers have adopted the perioperative use of corticosteroids remains unknown.

OBJECTIVES

To assess temporal trends, between-hospital variation, and determinants of perioperative intravenous corticosteroid use during CABG surgery.

METHODS

We identified all patients admitted for CABG surgery in the Premier Healthcare Database (2003-2014), a large US-based inpatient database. We determined the proportion of patients administered prophylactic corticosteroids on the day of CABG surgery. Linear time-series models were used to estimate the rate and trend of corticosteroid use over time. Separate multivariable generalized estimating equation models were used to quantify the variation in and determinants of perioperative corticosteroid use.

RESULTS

Of 401 788 eligible patients who underwent a CABG surgery between 2003 and 2014, 20% (n = 80 681) were administered intravenous prophylactic perioperative corticosteroids (methylprednisolone, dexamethasone, or hydrocortisone). Corticosteroid use increased from 17.5% in 2003 to 22.6% in 2014 (annual rate = 0.42%; P < .001). Individual hospitals accounted for >50% of variation in corticosteroid use. High between-hospital variation was also observed, and the probability of utilization was ≥32.4% in the upper versus ≤3.4% in the bottom quartiles of hospitals.

CONCLUSION

Prophylactic corticosteroid administration during CABG has increased gradually since 2003. To further evaluate the risk-benefit trade-off associated with their use, we believe a large-scale outcomes study is warranted to assess this highly variable practice.

Management of postoperative atrial fibrillation after cardiac surgery

PURPOSE OF REVIEW

Postoperative atrial fibrillation (POAF) occurs commonly after cardiac surgery and is associated with a number of adverse outcomes. This article will review the available evidence on the prevention and treatment of atrial fibrillation after cardiac surgery. Using this knowledge, we propose a conceptual framework on the management of patients with POAF during various phases after cardiac surgery.

RECENT FINDINGS

Perioperative β-blockade is the cornerstone in preventing POAF after cardiac surgery. Results from randomized trials do not support routine use of colchicine or corticosteroids to prevent POAF. There is no study examining the impact of rate versus rhythm control on 'hard' clinical outcomes such as mortality or stroke in the cardiac surgical population. Furthermore, there is a paucity of research on the optimal timing and choice of oral anticoagulation among POAF cardiac surgical patients who are at risk for stroke.

SUMMARY

In spite of the plethora of therapies available to treat and prevent POAF in the cardiac surgical population, there is little data to address whether they can improve key clinical outcomes such as death or stroke. Guideline recommendations on rate/rhythm control and oral anticoagulation for stroke prevention in the cardiac surgical population are largely extrapolated from studies of nonsurgical atrial fibrillation patients. Further research is needed to address these key atrial fibrillation management issues specific to the cardiac surgical population.

Use of short-term steroids in the prophylaxis of atrial fibrillation after cardiac surgery

OBJECTIVES

To assess the effectiveness of corticosteroids in the prophylaxis of postoperative atrial fibrillation (AF) in patients undergoing elective coronary artery bypass grafting or valvular heart surgery in terms of reducing its incidence and decreasing the length of hospital stay.

METHODS

This prospective double blinded randomized study was conducted at Queen Alia Heart Institute (Amman, Jordan) from June 2014 to June 2015 on 340 patients who underwent their first on-pump elective coronary artery bypass grafting (CABG) alone or combined with valvular surgery. Inclusion criteria consisted of elective first time CABG or combined with valvular surgery, use of β-adrenergic blockade, and normal sinus rhythm. Exclusion criteria included a history of heart block, previous episodes of AF or flutter, uncontrolled diabetes mellitus, history of peptic ulcer disease, systemic bacterial or mycotic infection, permanent pacemaker, and any documented or suspected supraventricular or ventricular arrhythmias. Patients were randomized into two equal groups (n = 170 each), then each group was subdivided into patients who underwent CABG alone (n = 120), and patients underwent valvular heart surgery with or without CABG (n = 50). In the treatment group, patients were given 1 g of methylprednisolone before cardiopulmonary bypass then 100 mg of hydrocortisone every 8 hours for the first 3 days postoperatively. The primary endpoint was the overall occurrence of postoperative AF.

RESULTS

AF developed in 21.1% (36 patients) in the treatment group in contrast to 38.2% (65 patients) in the control group (p < 0.05). In the subdivided groups (CABG only), approximately 20% (24 patients) developed AF in the treatment group in contrast to 35% (42 patients) in the control group (p < 0.05). In the other group, (CABG + VALVE) 24% (12 patients) developed AF compared with 46% (23 patients) in the control group (p < 0.05). The length of hospital stay was 6.02 ± 11.23 days in the treatment group while it was 5.98 ± 1.86 days in the control group, which was found to be statistically nonsignificant. No statistical significant difference in the rate of postoperative complications including mediastinitis as well superficial wound infections was observed between the two groups.

CONCLUSION

Prophylactic short-term use of steroids both intraoperatively and postoperatively proved to be safe and effective in reducing the incidence of postoperative AF in patients undergoing CABG alone or combined with valve surgery.

Efficacy of methylprednisolone and lignocaine on propofol injection pain: A randomised, double-blind, prospective study in adult cardiac surgical patients

BACKGROUND AND AIMS

Propofol (2, 6-di-isopropylphenol) used for the induction of anaesthesia often causes mild to severe pain or discomfort on injection. We designed this double-blind study to compare the efficacy of methylprednisolone and lignocaine in reducing the pain of propofol injection in patients scheduled for cardiac surgery.

METHODS

A total of 165 adult patients, scheduled for elective cardiac surgery, were divided into three groups: saline (group S, n = 55), lignocaine 20 mg (Group L, n = 55) and methylprednisolone 125 mg diluted into 2 ml of distilled water (Group MP, n = 55). Drugs were administered after tourniquet application and occlusion was released after 1 min and 1/4^th of the total dose of propofol (2 mg/kg) was administered at the rate of 0.5 ml/s. Pain on propofol injection was evaluated by four-point verbal rating scale. Statistical methods used included Student's t-test and Chi-square test/Fisher's exact test.

RESULTS

The overall incidence of pain was 70.9% in the saline group, 30.9% in the lignocaine group and 36.4% in the methylprednisolone group. The intensity of pain was significantly less in patients receiving methylprednisolone and lignocaine than those receiving saline (P < 0.012).

CONCLUSION

Pre-treatment with intravenous methylprednisolone was found to be as effective as lignocaine in reducing propofol injection-induced pain.