Off-pump Patients Research Articles

Octopus follow-up: 20 year prognosis in patients randomized to on-pump CABG, off-pump CABG or PCI

BackgroundThe very long-term outcomes of off-pump versus on-pump Coronary Artery Bypass Grafting (CABG) and Percutaneous Coronary Intervention (PCI) are largely unclear. We linked 20-years outcomes of two randomized trials to evaluate re-intervention and mortality outcomes for on-pump CABG, off-pump CABG and PCI. MethodsA data linkage project was performed using data as registered within the Netherlands Heart Registration (NHR), Statistics Netherlands (CBS) and the Octopus trials. Between 1998 and 2000, these trials randomized patients with coronary artery disease to on-pump versus off-pump CABG (OctoPump trial), or to PCI versus off-pump CABG (OctoStent trial). With data linkage, the original 5 years follow-up time for clinical events was extended to 20 years, including mortality and coronary reinterventions. ResultsAfter 20 years, in the OctoPump trial all-cause mortality was 50.0% after on-pump, and 46.5% after off-pump CABG. There was no difference in the combined outcome of mortality and re-interventions (HR 0.82, 95% CI 0.59–1.12). In the OctoStent trial, all-cause mortality was 56.7% after PCI and 52.5% after off-pump CABG. There was no difference in the combined outcome of mortality and re-interventions (HR 0.76, 95% CI 0.57–1.04). Off-pump CABG patients underwent less re-interventions than PCI patients (HR 0.52, 95% CI 0.33–0.80). ConclusionThis study revealed no differences in 20-year survival between patients randomized to on-pump versus off-pump CABG, or to PCI versus off-pump-CABG. However, off-pump CABG patients underwent less re-interventions than PCI patients.

The impact of pre-operative uric acid levels on post-operative renal outcomes in off-pump coronary artery bypass grafting patients

Background: Elevated pre-operative uric acid levels significantly impact post-operative renal outcomes in off-pump CABG patients, increasing the risk of acute kidney injury, as evidenced by higher serum creatinine and reduced urine output. Methods: This cross-sectional study was conducted in Department of Cardiac Surgery, Bangabandhu Sheikh Mujib Medical University (BSMMU), Shahbag, Dhaka, Bangladesh from January 2021 to December 2022. Total 160 patients undergoing off pump CABG were divided into two groups, group A and group B, each containing 80 patients. In group A, uric acid level was <7 mg/dl for male and <6 mg/dl for female and in group B, it was >7 mg/dl and >6 mg/dL for female. Results: The demographic characteristics, pre-operative serum UA levels and serum creatinine levels between the two groups was not statistically significant. Group A had shorter operative times (mean 265.21±53.33 minutes) compared to Group B (mean 327.04±44.32 minutes), with more patients in Group-B undergoing longer surgeries (>360 minutes). Group-B also had more grafts (mean 4.4 vs 3.6), higher serum creatinine (1.91 vs 1.17 mg/dl), bilirubin (0.8 vs 0.7 mg/dl), and lower urine output (mean 47.52 vs 95.37 ml/hour), all statistically significant (p<0.001). Conclusions: This study concludes that there is significant impact of pre-operative uric acid levels on post-operative renal outcomes in off-pump CABG patients.

Predominant Use of Bilateral Internal Mammary Arteries in Off-Pump Coronary Artery Bypass Surgery

Bilateral internal mammary artery (BIMA) in coronary artery bypass grafting (CABG) has been shown to provide long-term clinical benefits over single internal mammary artery (SIMA) grafting. Nevertheless, the perceived technical complexity of the procedure and concerns about potential early postoperative complications, particularly sternal wound infections have led to a utilization rate of BIMA grafting of less than 5% in the United States. We systematically compared early (30-day) post-operative outcomes between the BIMA and SIMA cohorts in patients with similar baseline characteristics. A retrospective single center study was conducted on matched patients, using stabilized inverse probability treatment weighting to mitigate bias between the two study cohorts. From 546 off-pump CABG patients initially identified, we examined 328 BIMA and 213 SIMA grafts from the matched samples. Despite utilizing 60.4% BIMA grafts, we observed similar rates of 30-day overall and cardiac mortality between the BIMA and SIMA groups. Rates of 30-day postoperative complications, including superficial and deep sternal wound infections, stroke, sepsis, acute kidney injury, and cardiac arrest, were similar between the two groups. Rates of 30-day overall and cardiac readmission were also similar. Additionally, median length of hospital stays, intensive care unit stay, and ventilation times were similar between the two groups. In conclusion, our data suggest that a BIMA utilization rate of 60.4% in off-pump CABG procedure is achievable without causing any significant increment in early post-operative complications, including deep sternal wound infection.

Off-Pump Reduces Risk of Coronary Bypass Grafting in Patients with High MELD-XI Score.

This study aimed to assess the influence of the model of end-stage liver disease without International Normalized Ratio (INR) (MELD-XI) score on outcomes after elective coronary artery bypass surgery (CABG) without (Off-Pump) or with (On-Pump) cardiopulmonary bypass. We calculated MELD-XI (5.11 × ln serum bilirubin + 11.76 × ln serum creatinine in + 9.44) for 3,535 consecutive patients having undergone elective CABG between 2009 and 2020. A MELD-XI threshold was determined using the Youden Index based on receiver operating characteristics. Propensity score matching and logistic regression was performed to identify risk factors for inhospital mortality and Major Adverse Cardiac and Cerebrovascular Event (MACCE). Patients were 68 ± 10 years old (76% male). Average MELD-XI was 10.9 ± 3.25. The MELD-XI threshold was 11. Patients below this threshold had somewhat lower EuroSCORE II than those above (3.5 ± 4 vs. 4.1 ± 4.7, p < 0.01), but mortality was almost four times higher above the threshold (below 1.5% vs. above 6.2%, p < 0.001). Two-thirds of patients received Off-Pump CABG. There was a trend towards higher risk in Off-Pump patients. Mortality was numerically but not statistically different to On-Pump below the MELD XI threshold (1.3 vs. 2.2%, p = 0.34) and was significantly lower above the threshold (4.9 vs. 8.9%, p < 0.02). Off-Pump above the threshold was also associated with less low-output syndrome and fewer strokes. Equalizing baseline differences by propensity matching verified the significant mortality difference above the threshold. Multivariable regression analysis revealed MELD-XI, On-Pump, atrial fibrillation, and the De Ritis quotient (Aspartate aminotransferase (ASAT)/Alanine Aminotransferase (ALAT)) as independent predictors of mortality. Elective CABG patients with elevated MELD-XI scores are at increased risk for perioperative mortality and morbidity. This risk can be significantly mitigated by performing CABG Off-Pump.

Indications and outcomes of second aortic procedures after acute type A dissection repair.

Aortic arch or aortic root replacement is not performed in all cases of acute type A aortic dissection (ATAD), and a second aortic procedure will become necessary over time for some patients. Indications and outcomes, of second aortic procedures have not been studied extensively. Characteristics and in-hospital outcomes of all patients undergoing surgical repair for type A acute aortic dissection were analysed and patients needing second aortic procedure during follow-up were identified. The latter group was divided in 2 subgroups: on-pump includes patients operated on using cardiopulmonary bypass and off-pump without cardiopulmonary bypass. A total of 638 patients underwent surgery for ATAD; 8% required a second aortic procedure. The most frequent indication for the second aortic procedure was dehiscence of suture lines (44%), followed by arch dilatation (24%). In-hospital mortality was 12%. Isolated ascending aorta replacement at the first surgery was associated with higher incidence of second aortic procedure (P = 0.006). Most patients in the on-pump group underwent a proximal reoperation (75%), with a mortality rate of 14.2%. In-hospital mortality of patients in the off-pump group was 7.7%. Long-term survival analysis showed no difference between groups (P = 0,526), Off-pump patients have greater likelihood of a second intervention during follow-up (P = 0.004). Extended aortic root surgery and customized aortic arch repair in ATAD could be reasonable to reduce the incidence and mortality of high-risk second aortic procedures.

Antiplatelet Resistance in Coronary Artery Bypass Grafting: A Systematic Review.

This systematic review examines the occurrence and implications of resistance to primary antiplatelet agents, aspirin and clopidogrel, often utilised in patients undergoing coronary artery bypass grafting (CABG), alongside the methodologies for assessment of such resistance. An extensive literature search across various databases such as PubMed, MEDLINE via Ovid, Embase, and Cochrane CENTRAL until May 2024 was conducted to identify studies evaluating antiplatelet resistance in on-pump and off-pump CABG patients. Following quality assessment, only high-quality studies were incorporated into this review. This review included 19 studies with 3,915 patients, four of which were randomised controlled trials and 15 were observational studies. Aspirin resistance incidence ranged from 11.0% to 51.5%, while clopidogrel resistance was 22%. Antiplatelet resistance, assessed through a wide variety of methods, was associated with a 13 times increase in the risk of vein graft occlusion and increased rates of mortality, myocardial infarction, and target vessel revascularisation in the case of clopidogrel resistance. The effect of cardiopulmonary bypass on antiplatelet resistance remains ambiguous. The academic literature lacks a standardised definition for antiplatelet resistance. Assessment methodologies greatly vary, leading to noninterchangeable outcomes. While aspirin resistance has a conflicting overall significant impact on adverse outcomes, clopidogrel resistance correlates with poorer clinical outcomes.

At the Right Place, at the Right Time. Reply to Vetrugno et al. Comparison between FlowTrac and Pulmonary Arterial Catheter in Off-Pump Cardiac Surgery Patients: "Why Did We Miss Our Appointment?". Comment on "Oh et al. Comparison between Fourth-Generation FloTrac/Vigileo System and Continuous Thermodilution Technique for Cardiac Output Estimation after Time Adjustment during Off-Pump Coronary Artery Bypass Graft Surgery: A

We thank Vetrugno et al. for their interest and comments [...].

Blood Products Utilization Status in Off-Pump Cardiac Surgery Patients.

Background: Transfusion support has an essential role in coronary artery bypass graft (CABG). The time-honored gold standard for CABG is the on-pump procedure (ONCAB); however, off-pump coronary artery bypass (OPCAB) is also a safe, cost-benefit procedure with fewer blood transfusion requirements. This study was performed to evaluate transfusion patterns in OPCAB due to the diversity of transfusion practices. Materials and Methods: This retrospective study was performed to determine the transfusion rate and triggers in OPCAB patients. Medical files of all patients undergoing OPCAB surgery at Sanandaj Tohid Hospital in 2014 were reviewed. Patients' demographics data, preoperative laboratory tests (PT, aPTT, Hb, Hct, Platelet count), underlying medical conditions, and their possible relation to further transfusions and the ward department in which the transfusion had taken place were extracted. SPSS 16 Chicago software, T-student Test, One Way Anova, and χ2 exam were applied for data analysis. P values ≤0.05was considered significant. Results: Among 91 elective OPCAB patients: 28(30.8%) women and 63(69.2%) men with mean age of 64.80±9.02 years, 63(69.23%) received a blood product. Mean utilization of PRBC, FFP, Platelet, and Cryoprecipitate were 2.17±2.044, 2.46±2.86, 2.86±3.80 and 0.40±2.10 units, respectively. ICU revealed the highest consumption rate for all products. Female sex (p<0.001), Hypertension (P=0.002), and low hemoglobin(P=0.004) were noted as predictive factors for transfusion. Conclusion: This study concluded that the transfusion rate in OPCAB is still very high in Iran (regarding a study in a countryside hospital) and that the highest utilization rate is seen in the ICU.

Comparison between FlowTrac and Pulmonary Arterial Catheter in Off-Pump Cardiac Surgery Patients: “Why Did We Miss Our Appointment?”. Comment on Oh et al. Comparison between Fourth-Generation FloTrac/Vigileo System and Continuous Thermodilution Technique for Cardiac Output Estimation after Time Adjustment during Off-Pump Coronary Artery Bypass Graft Surgery: A Retrospective Cohort Study. J. Clin. Med. 2022, 11, 6093

We read with great interest the study by Chahyun Oh et al., which compared estimates of cardiac output (CO) provided by the FloTrac system (CO-FloTrac) with those obtained with continuous thermodilution (COcont) after time adjustments using continuous recordings of intraoperative physiological datal [...].

Changes in transcranial near-infrared spectroscopy values reflect changes in cardiac index during cardiac surgery.

To determine whether changes in transcranial near-infrared spectroscopy (NIRS) values reflect changes in cardiac index (CI) in adult cardiac surgical patients. Single-center prospective post hoc analysis. University hospital. One hundred and twenty-four adult patients undergoing cardiac surgery. In each patient, several CI measurements were taken, and NIRS values were collected simultaneously. We used a hierarchical linear regression model to assess the association between NIRS values and CI. We calculated a crude model with NIRS as the only factor included, and an adjusted model, where mean arterial pressure, end-tidal CO2 , and oxygen saturation were used as confounding factors. A total of 1301 pairs of NIRS and CI values were collected. The analysis of separate NIRS and CI pairs revealed a poor association, which was not statistically significant when adjusted with the chosen confounders. However, when the changes in NIRS from baseline or from the previous measurement were compared to those of CI, a clinically and statistically significant association between NIRS and CI was observed also in the adjusted model. Compared to the baseline and to the previous measurement, respectively, the regression coefficients with 95% confidence intervals were 0.048 (0.041-0.056) and 0.064 (0.055-0.073) in off-pump coronary artery bypass patients and 0.022 (0.016-0.029) and 0.026 (0.020-0.033) in patients who underwent cardiopulmonary bypass. In an unselected cardiac surgical population, the changes in NIRS values reflect those in CI, especially in off-pump coronary artery bypass patients. In this single-center post hoc analysis of data from a prospectively collected database of cardiac surgery patients, paired measurements of cardiac output and NIRS revealed that while there was a no correlation between individual paired measurements, a small correlation was found in changes in the two measurements from baseline values. This highlights a potential to utilize changes in NIRS from baseline to suggest changes in cardiac output in cardiac surgical populations.

The association of body composition assessment with hospital length of stay in off-pump coronary artery bypass patients.

Bioelectrical impedance analysis is a widely available, non-invasive method for body composition assessment. To elucidate the perioperative body composition alterations and their prognostic utility for hospital length of stay (LOS) in low risk, off-pump coronary artery bypass (OPCAB) patients. Fifty patients undergoing elective OPCAB were included in the study. Body composition assessments were performed 1 day before the scheduled surgery and on the 6th postoperative day. Patients were grouped into < 9 days (n = 29, 58%) and ≥ 9 days (n = 21, 42%). Multivariate logistic regression analysis was performed to create a body composition-based screening panel for prolonged hospital stay. No significant differences in anthropometric measurements, clinical characteristics or occurrence of postoperative complications were detected between the study groups. Patients with longer hospitalization had significantly higher content of fat mass (FM%) and fat mass index (FMI), and significantly lower content of fat free mass (FFM%) baseline parameters (p = 0.011, p = 0.04 and p = 0.012, respectively). High FM% values had 15-fold, low FFM% values had 13-fold and high FMI values had 7-fold higher risk of experiencing longer stay in the hospital (p = 0.001, p = 0.001 and p = 0.005, respectively). The combined panel of three variables (higher FM%, lower FFM% and higher FMI) had 16-fold higher risk of longer hospitalization (adjusted OR = 16.40; 95% CI: 3.52-76.34; p = 0.0004). Preoperative high FM and low FFM content are independent predictors of prolonged hospital length of stay in normal- and increased-BMI patients after OPCAB.

Retrospective observational analysis of a coronary artery bypass grafting surgery patient cohort: Off-pump versus on-pump.

To determine whether surgical technique has an effect on prognosis in coronary artery bypass grafting (CABG). Retrospective observational. Single center. All the off-pump (OPCABG) and on-pump (ONCABG) patients at Turku University Central Hospital in 2018. None. After propensity score matching, perioperative, 1-year and 3-year mortality did not differ between the groups. The ONCABG patients received more allogenic red blood cells (1.3 vs. 0.6 units, p=0.020), autologous red blood cells (564 vs. 285ml, p<0.001) and crystalloids (3388 vs. 2808ml, p<0.001), and had higher postoperative values of troponin T (581 vs. 222, p=0.001) and lactate (1.69 vs. 1.23, p<0.001) than the OPCABG patients. The both techniques seem equally safe. However, there may be some benefits to avoiding using a heart-lung machine, such as lower infused fluid volumes. Myocardial damage may also be milder and postoperative hemodynamics more balanced in OPCABG patients, based on lower levels of troponin T and lactate.

Textbook outcome in lung transplantation: Planned venoarterial extracorporeal membrane oxygenation versus off-pump support for patients without pulmonary hypertension.

Planned venoarterial extracorporeal membrane oxygenation (VA ECMO) is increasingly used during bilateral orthotopic lung transplantation (BOLT) and may be superior to off-pump support for patients without pulmonary hypertension. In this single-institution study, we compared rates of textbook outcome between BOLTs performed with planned VA ECMO or off-pump support for recipients with no or mild pulmonary hypertension. Patients with no or mild pulmonary hypertension who underwent isolated BOLT between 1/2017 and 2/2021 with planned off-pump or VA ECMO support were included. Textbook outcome was defined as freedom from intraoperative complication, 30-day reintervention, 30-day readmission, post-transplant length of stay >30 days, 90-day mortality, 30-day acute rejection, grade 3 primary graft dysfunction at 48 or 72 hours, post-transplant ECMO, tracheostomy within 7 days, inpatient dialysis, reintubation, and extubation >48 hours post-transplant. Textbook outcome achievement was compared between groups using multivariable logistic regression. Two hundred thirty-seven BOLTs were included: 68 planned VA ECMO and 169 planned off-pump. 14 (20.6%) planned VA ECMO and 27 (16.0%) planned off-pump patients achieved textbook outcome. After adjustment for prior BOLT, lung allocation score, ischemic time, and intraoperative transfusions, planned VA ECMO was associated with higher odds of textbook outcome than planned off-pump support (odds ratio 3.89, 95% confidence interval 1.58-9.90, p=0.004). At our institution, planned VA ECMO for isolated BOLT was associated with higher odds of textbook outcome than planned off-pump support among patients without pulmonary hypertension. Further investigation in a multi-institutional cohort is warranted to better elucidate the utility of this strategy.

Perioperative dexmedetomidine reduces delirium after coronary artery bypass graft surgery: A prospective, single-blind, observational study.

Delirium is a commonly seen complication of cardiac surgery. Dexmedetomidine, by its anti-inflammatory properties and other effects, can attenuate postoperative delirium. The aim of this work was to study the incidence of delirium after coronary artery bypass graft surgery, and to compare the effects of dexmedetomidine and propofol on the incidence of postoperative delirium in coronary artery bypass graft surgery patients. A prospective, observational study was conducted on 180 consecutive patients undergoing off-pump or on-pump coronary artery bypass graft surgery. The patients were administered either intravenous dexmedetomidine (n = 90) or propofol (n = 90) after hemostasis was achieved, till they were ready for weaning from the ventilator. The Confusion Assessment Method was used to assess the incidence of postoperative delirium. A total of 25 (13.8%) patients developed delirium after coronary artery bypass graft surgery. Sedation with dexmedetomidine was associated with a significantly reduced incidence of postoperative delirium (8.9% v 18.9% propofol, P = 0.049). Subgroup analyses showed reduced incidence of postoperative delirium in off-pump patients compared to on-pump coronary artery bypass graft patients (3.3% vs. 20%, P = 0.009 dexmedetomidine group and 11.6% vs. 33.3%, P = 0.047 propofol group respectively). The mean age of the patients who had delirium was significantly more (64.9 ± 8.1 years vs. 52.5 ± 5.8 years, P = 0.046) compared to those who did not have delirium. Administration of dexmedetomidine-based sedation resulted in the reduced incidence of postoperative delirium compared to propofol-based sedation in patients after coronary artery bypass graft surgery.

Comparison of new-onset post-operative atrial fibrillation between patients receiving carvedilol and metoprolol after off-pump coronary artery bypass graft surgery.

Post-operative atrial fibrillation (POAF) is a common complication of coronary artery bypass graft (CABG) surgery. Previous studies suggest carvedilol is more effective than metoprolol in preventing POAF in on-pump CABG. This study investigated if the same benefit would be seen inoff-pump CABG. This single-center, retrospective reviewcompared rates of new-onset POAF between adult patients who received carvedilol and metoprolol after off-pump CABG surgery. Safety endpoints included hypotension, bradycardia, dyspnea, and the composite. Multivariate logistic regression was conducted to identify associations between demographics, potential confounders, and beta-blocker dose and POAF. Kaplan-Meier plots and Cox proportional-hazards models examined differences in time-to-event for POAF. 134 patients were included (34 carvedilol and 100 metoprolol). The mean age was 63years, 70.9% were male, 85% had history of hypertension, 3.7% had history of heart failure with reduced ejection fraction, and 38.8% were taking beta blockers prior to admission. POAF developed in 2 patients (5.8%) in the carvedilol group and 24 patients (24.0%) in the metoprolol group (odds ratio 0.17 [95% CI 0.03-0.83], p = 0.023). Safety endpoints occurred in 10 carvedilol (29.4%) and 44 metoprolol (44.0%) patients (p = 0.134). Hypotension and dyspnea rates were similar between groups; bradycardia occurred more commonly among metoprolol-treated patients (p = 0.040). Time-to-event analyses revealed a hazard ratio = 0.22 (95% CI 0.05-0.93, p = 0.040) for carvedilol use. In this single-center, retrospective study of off-pump CABG patients, carvedilol was associated with reduced POAF risk and enhanced safety compared to metoprolol.

The Impact of Diabetes on Acute Kidney Injury After Off-Pump Coronary Artery Bypass Grafting.

Acute kidney injury (AKI) is one of the most frequent complications after coronary artery bypass grafting. Previous studies have shown that diabetes is a key pathogenic factor. But how diabetes is related to AKI in off-pump CABG patients still is in debate. Here, we aim to study the relationship between diabetes and AKI after off-pump coronary artery bypass grafting (off-pump CABG). Patients who underwent off-pump CABG from April 2017 to December 2020 in The First Affiliated Hospital of USTC were enrolled in this retrospective study. AKI was defined and classified, according to the criteria proposed by the Acute Kidney Injury Network. The incidence risk of acute kidney injury was measured by logistic regression and compared. A total of 395 patients, who underwent off-pump CABG, were included in this study. The postoperative acute kidney injury rate for a patient with diabetes was significantly higher than for patients without diabetes (x2 = 5.09, P = 0.024). Logistic regression analysis showed that patients with diabetes have a much higher risk with acute kidney injury occurring after off-pump coronary artery bypass grafting (OR 1.852, 95% CI 1.161 - 2.954, P = 0.01). Diabetes is an independent risk factor for postoperative AKI for patients undergoing off-pump CABG.

Comparison of traditional and upper thoracic epidural analgesia after off-pump coronary artery bypass graft surgery: A Quasi-experimental study.

Background and AimsSurgical trauma initiates changes in central and peripheral nervous systems that need to be treated therapeutically to facilitate postoperative pain. The quality of postoperative analgesia is expected to affect clinical outcomes positively. Albeit optimal pain relief following cardiac surgery is often complex, researchers have tried to explore several techniques other than conventional ones during the last decade to find a unique analgesic method for postcardiac surgical patients. This study aims to find a unique analgesic approach that maximizes patient satisfaction after off‐pump coronary artery bypass graft (OPCABG) surgery.MethodsThe current study will compare the analgesic effect of upper thoracic epidural analgesia (TEA) with conventional analgesia after OPCAB graft surgery. For this, we will use a Quasi‐experimental study design. Patients admitted for coronary artery bypass graft (CABG) surgery will be assigned into two groups. The control group (conventional) will receive intravenous opioids and nonsteroidal anti‐inflammatory medications, and the study (case) group (TEA) will receive Inj. Bupivacaine 0.25% as an infusion through the epidural catheter. Physiologic parameters like hemodynamic and respiratory variables and pain scores will be recorded in predesigned format periodically.ResultsWe expect to analyze a total of 130 consecutive off‐pump CABG surgery patients in Group A (Case, 65 patients) and Group B (Control, 65 patients). Study variables will be the visual analog scale score, hemodynamic parameters (heart rate, mean arterial pressure, and respiratory parameters (respiratory rate, PaO2, PaCO2, PEFR, FEV1). After data collection, the result will be analyzed and published in the public domain and in journals.ConclusionWe expect thoracic epidural analgesia with local anesthetics will be a reliable postoperative analgesic option.

A Comparative Study of Bilateral Erector Spinae Block Versus Intravenous Dexmedetomidine for Perioperative Pain Management in Patients Undergoing Off-Pump Coronary Artery Bypass Grafting - A Single-Blind Randomized Controlled Trial

Regional analgesia, along with general anesthesia, reduce postoperative pain. In this study, the authors compared the erector spinae plane (ESP) block having dexmedetomidine as an adjuvant with conventional pain management along with intravenous dexmedetomidine. Prospective randomized single-blinded trial. Tertiary care teaching hospital. All of the patients scheduled for elective off-pump coronary artery bypass grafting with an ejection fraction of >45%. After obtaining institutional ethical committee approval, 130 patients were randomized into Group E and Group D. Group E patients received ESP block bilaterally with 25 mL of bupivacaine plus 0.5 μg/kg of dexmedetomidine. The patients in Group D received conventional intravenous analgesia, as well as a 0.7 μg/kg of dexmedetomidine bolus, followed by a 0.3 μg/kg dexmedetomidine infusion during surgery and continued postoperatively for 24 hours. Group E patients received 8 mL/h of bupivacaine infusion bilaterally for 24 hours. The primary outcome assessed was pain scores in the postoperative period. The secondary outcomes assessed were postoperative rescue analgesic consumption, time to first rescue analgesia, intraoperative fentanyl consumption, duration of mechanical ventilation, and duration of intensive care unit (ICU) stay. Both groups were comparable in demographic characteristics. The postoperative pain scores from 4 hours to 12 hours were lower in Group E compared with Group D. The pain scores at 24 hours were not significantly different between groups. Postoperative fentanyl consumption in Group E (99.23 ± 50.19 μg) was significantly lower than in Group D (181.15 ± 82.92 μg), with a p value of 0.001. Time to first rescue analgesia was significantly longer in Group E, with a median score of 8 hours when compared with that of 4 hours in Group D, with a p value of 0.01. Intraoperative fentanyl consumption was significantly lower in Group E (392.15 ± 55.36 μg) compared with Group D (604.00 ± 131.87 μg; p=0.001). There were no significant differences in the duration of mechanical ventilation in both groups. Duration of ICU stay was significantly lower in Group E (51.95 ± 8.54 hours) when compared with Group D (59.06 ± 8.68 hours) (p=0.001). Erector spinae fascial plane blocks appeared to reduce postoperative pain scores in off-pump coronary artery bypass graft patients. Furthermore, ESP block was beneficial in terms of less intraoperative and postoperative opioid consumption, longer time to first rescue analgesia, and shorter ICU stay.

Induced blood oxidation in myocardial revascularization

Background: The use of artificial circulation in surgical myocardial revascularization is one of the key pathogenetic factors in the development of the oxidative stress and systemic inflammatory response in the postoperative period. Aims: the purpose of the study was to describe the dynamics of the induced blood oxidation parameters during coronary artery bypass surgery in the conditions of artificial circulation and on the working heart. Methods: The study included 64 patients who underwent coronary bypass surgery, with 31 (48.4%) on-pump patients and 33 (51.6%) off-pump patients. The oxidative stress simulations were conducted under the in vitro conditions. The blood oxidation-induced values were studied using a biological oxygen monitor. Results: In patients with coronary heart disease, regardless of the choice of the revascularization method (on-pump / off-pump), we observed statistically significantly (p 0.05) higher initial and maximum blood oxidation rates, the oxidative activity factor, and a shorter initiation period than those in healthy volunteers. No significant differences were found by the inter-group comparison analysis both 10 days and 6 months post-surgery. Conclusion: The indicators of induced blood oxidation do not depend on the method of revascularization during coronary bypass grafting (artificial circulation or a working heart). The changes in the parameters indicating activation of the oxidative and antioxidant blood systems may be transient by their nature and occur in the early postoperative period.

Measuring the Systemic Inflammatory Response to On- and Off-Pump Coronary Artery Bypass Graft (CABG) Surgeries Using the Tryptophan/Kynurenine Pathway

Background: Cardiac surgeries induce many inflammatory responses with remarkable clinical implications. Tryptophan (Trp) is a precursor for serotonin, melatonin and kynurenine (Kyn). Plasma kynurenic acid (Kyna) and Kyn concentrations are thought to be related to the severity of inflammation. Plasma Trp/Kyn ratio is used to measure inflammatory cytokine activity. Methods: We performed the current longitudinal study in a tertiary care center and included 62 patients divided into two groups; group A (on-pump CABG patients) and group B (off-pump CABG patients). Plasma Trp and Kyn were measured using the high-performance liquid chromatography (HPLC) technique. Serum interlukin-6 (IL-6) and white blood cells (WBCs) were measured using ELISA and routine blood count, respectively. Results: The present study revealed that the intraoperative levels of plasma Kyn, IL-6 and WBCs were significantly increased while the plasma Trp/Kyn ratio was significantly decreased in both the groups; however, the changes were more significant in the on-pump CABG group. Moreover, the levels in both the groups returned to preoperative levels 72 h postoperative. Our study has shown that WBCs is positively correlated with IL-6, but has negative correlation with Trp/Kyn ratio. Conclusions: Kyn and Trp/Kyn ratio might be utilized as markers of the severity of inflammation in major surgery. In addition, off-pump CABG might be more preferable than on-pump CABG regarding stress and release of inflammatory markers.