Off-pump Surgery Research Articles

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.

Transit-time flow measurement parameters after protamine infusion in CABG surgeries.

The objective of this study is to evaluate protamine sulfate effects on graft's blood flow by comparing transit-time flow measurement (TTFM) values before and after protamine administration. This is an observational study with data collected between years 2018 and 2020. Immediate graft patency was evaluated using TTFM. Only patients with TTFM parameters registered before and after protamine infusion were included. The main three parameters studied were: mean graft flow (MGF), pulsatility index (PI), and diastolic flow (DF). In the first analysis, all conduits were evaluated regardless of the surgical technique used. In a second analysis, on-pump and off-pump groups were compared. Evaluated grafts were left internal thoracic artery, saphenous vein graft (SVG), radial artery, and right internal thoracic artery. Since SVG was numerically the most used graft, an exclusive analysis was created. Our study included 575 patients, resulting in a total of 1686 grafts, mean 2.93 grafts/patient. Off-pump surgery was performed in 158 patients. Before protamine infusion, inadequate TTFM parameters were observed in 3.8% of grafts. Overall, after protamine administration, MGF decreased in all grafts, but its reduction was not statistically significant. PI values increased in the SVG and DF values reduced in LIMA grafts. SVG group analysis showed that after protamine PI values were higher in OM1 and RCA. DF values increased in RCA. The comparison between off and on-pump surgeries, showed that in off-pump cases TTFM measures did not present statistically significant differences. Significant variations were observed in TTFM values before and after protamine administration. Although different, those values remained within the normal reference ranges. We recommend that flow measurement should be performed before protamine infusion.

Effects of vitamin D level and oxidant-antioxidant balance on postoperative morbidity in diabetic and non-diabetic patients undergoing off-pump bypass surgery

Objective: Atherosclerosis is still a major problem that cannot be resolved despite significant developments in cardiology and is the leading cause of death over worldwide. Endothelial dysfunction is triggered by multifactorial causes of oxidative stress in the cellular dimension and is associated with atherosclerosis. Despite the associated mechanisms are still unclear vitamin D deficiency is considered as one of the causing factors. Patient-method: In our study; randomized 100 consecutive patients with advanced atherosclerotic heart disease were classified as Group A (<20 ng /dl), Group B (21-29 ng /dl) and Group C (≥30 ng /dl) according to the vitamin D levels. They were underwent off-pump coronary artery bypass grafting. Clinical data of all cases, oxidant/antioxidant balance and thiol / disulfide levels were collected also. Results: Preoperative CRP and procalcitonin levels were significantly high in Group A (p=0.028 and p=0.031) according to the other vitamin D levels. There was no statistically significant difference (p=0.46) between all groups in terms of total antioxidant status (mmol /L). In the vitamin D deficient group (<20 ng /ml), oxidant /antioxidant index (OSI) was significantly high (p=0.0378). There was no significant difference between total and native thiol levels and disulfide / thiol contents. While the duration of intubation periods were similar (p=0.056), intensive care and hospital stay times were significantly higher in the Group A with diabetics, respectively; p=0.0034, p=0.00021. There was no significant difference between the other groups. This suggests that the inflammatory process, and oxidative stress one of the basic mechanisms of atherosclerosis, may be more severe in the vitamin D deficient group, especially in diabetics.Our results confirm vitamin D, antioxidant and anti-inflammatory activity.

Can Right Ventricular Branch Bypass Alleviate Right Ventricular Dysfunction?

Right ventricle (RV) dysfunction after a coronary artery bypass grafting procedure is a challenge that adversely affects RV filling pressure and contraction. This study sought to determine whether additional bypass of an RV branch would lessen RV dysfunction. Patients with severe right coronary artery (RCA) stenosis were divided into 2 groups. Group 1 patients (n = 50) had a single distal bypass on the RCA. Group 2 patients (n = 50) had both distal RCA and additional bypass on the RV branch of the RCA. Right ventricular function was examined by echocardiogram by measuring transannular plane systolic excursion, fractional area change, tissue Doppler S-wave velocity, and inferior vena cava diameter. Transannular plane systolic excursion and fractional area change measurements rapidly decreased below the cutoff in both groups, but group 2 patient values reached normal limits at 90 days. Tissue Doppler S-wave velocity reached the normal limit in 7 days. Inotropic agents were required in 11 patients in group 1 and 2 patients in group 2 (P = .013). The mean (SD) intensive care unit stay was 2.11 (1.12) days and 1.45 (0.71) days (P = .033), and the hospital stay was 7.32 (1.44) days and 6.22 (0.45) days in groups 1 and 2, respectively (P = .027). The data in this study suggest that an additional graft on the RV branch of the RCA (eg, conus, marginal, any good runoff vessels on the RV) prevents severe RV dysfunction and allows for rapid recovery of RV dysfunction after off-pump coronary surgery.

Influence of Mild Thyroid Dysfunction on Outcomes after Off-Pump Coronary Artery Bypass Surgery.

We retrospectively evaluated the association between preoperative mild thyroid dysfunction (subclinical hypothyroidism [SCH] or low triiodothyronine [T3] syndrome) and outcomes in patients who underwent off-pump coronary surgery (OPCAB). Further, 800 patients (2015–2020) were divided into euthyroid, low T3, and SCH groups. The primary outcome assessed the association with composite endpoints (myocardial infarction, prolonged mechanical ventilation [>24 h], acute kidney injury, and 30-day/in-hospital mortality). The secondary outcome assessed the association with long-term mortality and 10% and 8% of the patients exhibited low T3 and SCH, respectively. Incidences of composite endpoints were significantly higher in the low T3 and SCH groups versus the euthyroid group (50.6%, 45.2%, 17.4%, respectively, p < 0.001). Multivariable regression analysis revealed chronic kidney disease, anemia, EuroSCORE, low T3, and SCH as independent risk factors of composite endpoints. The long-term mortality rate (median follow-up, 30 months) was higher in the low T3 and SCH groups than in the euthyroid group (9.6%, 11.3%, 2.4%, respectively, p < 0.001). In the absence of overt thyroid dysfunction, low T3 and SCH were associated with increased risk of adverse outcomes after OPCAB. Moreover, the adverse influences of low T3 and SCH seem to extend to long-term mortality, implying that routine thyroid function tests may enhance accurate risk stratification.

The use of intraoperative transit time flow measurement can reduce postoperative myocardial injury.

This study investigates the relationship between the use of transit time flow measurement (TTFM) and postoperative myocardial injury in off-pump coronary artery bypass grafting (OPCABG). In this retrospective study, we collected basic data from patients hospitalized for OPCABGin the Department of Cardiothoracic Surgery, Changzhou Second People's Hospital Affiliated with Nanjing Medical University. According to the academic research consortium (ARC)-2 definition of significant myocardial injury, we used cardiac troponin I >2380 ng/L as a criterion for significant postoperative myocardial injury. We use logistic regression and forest plots to assess the association of TTFM use with myocardial injury outcomes. One hundred and forty-six patients were included in this study. The overall median age of these patients was 65.05 years, and 32 (21.92%) experienced a postoperative myocardial injury. TTFM was independently associated with the incidence of postoperative myocardial injury (odds ratio = 0.34 [95% confidence interval = 0.15-0.78]; p = .01), and we found similar trends in regression analyses across subgroups of sex, age, number of bridging vessels, hypertension, diabetes mellitus, BMI, and percutaneous coronary revascularization. One hundred andsixpatients were followed for 1-year vessel permeability, and sevenpatients (6.6%) were occluded. The use of TTFM is independently associated with a reduced incidence of postoperative myocardial lesions during off-pump coronary bypass surgery. The TTFM procedure in OPCABGdeserves to be actively promoted to reduce the incidence of postoperative myocardial injury.

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.

Unilateral left-sided thoracoscopic ablation of atrial fibrillation concomitant to minimally invasive bypass grafting of the left anterior descending artery.

OBJECTIVESThoracoscopic ablation for atrial fibrillation (AF) and minimally invasive direct coronary artery bypass (MIDCAB) with robot-assisted left internal mammary artery (LIMA) harvesting may represent a safe and effective alternative to more invasive surgical approaches via sternotomy. The aim of our study was to describe the feasibility, safety and efficacy of a unilateral left-sided thoracoscopic AF ablation and concomitant MIDCAB surgery.METHODSRetrospective analysis of a prospectively gathered cohort was performed of all consecutive patients with AF and at least a critical left anterior descending artery (LAD) stenosis that underwent unilateral left-sided thoracoscopic AF ablation and concomitant off-pump MIDCAB surgery in the Maastricht University Medical Centre between 2017 and 2021.RESULTSTwenty-three patients were included [age 69 years (standard deviation = 8), paroxysmal AF 61%, left atrial volume index 42 ml/m2 (standard deviation = 11)]. Unilateral left-sided thoracoscopic isolation of the left (n = 23) and right (n = 22) pulmonary veins and box (n = 21) by radiofrequency ablation was succeeded by epicardial validation of exit- and entrance block (n = 22). All patients received robot-assisted LIMA harvesting and off-pump LIMA-LAD anastomosis through a left mini-thoracotomy. The perioperative complications consisted of one bleeding of the thoracotomy wound and one aborted myocardial infarction not requiring intervention. The mean duration of hospital stay was 6 days (standard deviation = 2). After discharge, cardiac hospital readmission occurred in 4 patients (AF n = 1; pleural- and pericardial effusion n = 2, myocardial infarction requiring the percutaneous intervention of the LIMA-LAD n = 1) within 1 year. After 12 months, 17/21 (81%) patients were in sinus rhythm when allowing anti-arrhythmic drugs. Finally, the left atrial ejection fraction improved postoperatively [26% (standard deviation = 11) to 38% (standard deviation = 7), P = 0.01].CONCLUSIONSIn this initial feasibility and early safety study, unilateral left-sided thoracoscopic AF ablation and concomitant MIDCAB for LIMA-LAD grafting is a feasible, safe and efficacious for patients with AF and a critical LAD stenosis.

Symptom progression following on-pump versus off-pump coronary artery bypass graft surgery in patients with peripheral arterial disease.

This study aims to examine whether cardiac surgery leads to symptom progression in the early postoperative period in patients with the peripheral arterial disease (PAD) and evaluate the difference between on-pump (OPCAB) and off-pump (ONCAB) coronary artery bypass graft surgery with regard to the symptom progression. This retrospective study included one hundred consecutive adult patients with PAD at Fontaine stage 2b (pain-free walking distance less than 100m) undergoing ONCAB and one hundred consecutive adult patients with PAD at Fontaine stage 2b (pain-free walking distance less than 100m) undergoing OPCAB. Symptom progression was defined as the development of ischemic rest pain (Fontaine stage 3). In the first week after surgery, 12 patients in the OPCAB group and 53 patients in the ONCAB group had postoperative symptom progression (p < 0.001). Rest pain resolved in most of these patients on the 15th postoperative day. At the end of the second month, rest pain resolved in all patients. Logistic regression analysis revealed that cardiac surgery with CPB, ABI < 0.5, postoperative nadir hct levels ≤ 25%, and intraoperative tissue hypoxia were independently associated with postoperative symptom progression. In summary, we found that cardiac surgery may lead to symptom progression in patients with severe claudication in the early postoperative period. Our results suggest that OPCAB may lead to lower rates of symptom progression compared to ONCAB.

Platelet Reactivity and Outcomes after Off-Pump Coronary Surgery in Acute Coronary Syndrome Patients

Ischemic and hemorrhagic complications are major determinants of survival in acute coronary syndrome (ACS) patients undergoing coronary surgery. We investigated the association of preoperative platelet reactivity to P2Y12 antagonists with ischemic and hemorrhagic complications after Off-Pump Coronary Artery Bypass surgery (OPCAB) in ACS patients who received dual anti-platelet therapy (DAPT) within 5 days prior to surgery. This prospective, observational study with 177 patients compared the incidence of perioperative major bleeding and major adverse cardiac events (MACEs) in relation to the tertile distribution of the % inhibitory response to P2Y12 antagonists, as measured by a thromboelastography platelet mapping assay. The incidences of perioperative major bleeding and MACEs were similar in relation to the tertile distribution of inhibitory response to P2Y12 antagonists. The % inhibitory responses to P2Y12 antagonists between patients who did or did not exhibit MACEs, and with or without major bleeding, were 58 ± 20% and 56 ± 20% (p = 0.578) and 57 ± 19% and 56 ± 21% (p = 0.923), respectively. In ACS patients who received DAPT close to OPCAB, the platelet inhibitory response to P2Y12 antagonists was not associated with ischemic or hemorrhagic complications. OPCAB may obviate the need for routine platelet function testing for ACS patients requiring DAPT and surgical revascularization. Clinical Registration Number: NCT02184884.

Tranexamic Acid and the Risk of Delirium after Off-Pump Surgery.

We investigated whether in patients undergoing off-pump coronary artery bypass grafting surgery a single bolus of 1 g tranexamic acid (TXA) impacts the risk of postoperative delirium using the propensity score matching approach. In 2,757 pairs, the risk of delirium was 4.2% (TXA group) and 5.0% (non-TXA group), with a relative risk in the TXA versus the non-TXA group of 0.83 (95% confidence interval: 0.65-1.07; p = 0.16). There was no significant interaction between TXA administration and renal function on the risk of delirium (p = 0.12). Data indicate that a single bolus of 1 g TXA does not increase the risk of delirium in patients undergoing off-pump surgery.

Off-Pump Coronary Artery Bypass Graft Surgery with Bilateral Internal Mammary Arteries in Left Main Coronary Artery Disease. Is There Any Benefit in 10-Year Mortality?

Background: The randomized controlled trials comparing coronary artery bypass graft (CABG) surgery versus percutaneous coronary intervention (PCI) included all types of surgical techniques (on-pump and off-pump) and different conduits (arterial and venous). Is it reasonable to assume that all surgical techniques are equal in terms of late mortality? Objectives: The aim of this study was to evaluate whether off-pump CABG surgery using both mammary arteries provides additional benefit over conventional revascularization using single mammary artery in terms of long-term survival for left main coronary artery (LMCA) disease. Methods: We conducted a retrospective, observational and comparative study (n=723) adjusted for risk. A stratified analysis was performed according to the use of single internal thoracic artery (SITA, n=144) or bilateral internal thoracic arteries (BITA, n=579) analyzing survival at 10 years after the intervention. Results: Survival at 10 years was significantly higher in BITA group (79.0%±3.4% vs 67.0%±4.9%, log-rank test, p &lt;0.01). This advantage was also observed in the risk-adjusted analysis (93.0%±4.6 vs 69.0%±5.7 respectively, p=0.03). The use of BITA was an independent predictor of 10-year survival (HR 0.57, 95% CI 0.37-0.87, p=0.01). Conclusion: The use of bilateral internal mammary arteries in patients with left main coronary artery disease undergoing off-pump coronary artery bypass grafting was associated with higher survival at 10 years.

Preoperative frailty based on laboratory data and postoperative health outcomes in patients undergoing coronary artery bypass graft surgery

BackgroundFrailty is associated with adverse surgical outcomes. Patients with cardiovascular diseases have many risk factors of frailty; thus, preoperative frailty evaluation is necessary to predict adverse outcomes after coronary artery bypass graft (CABG) surgery. Laboratory data based-frailty assessments are objective and not time-consuming, addressing the need for an accurate but simple frailty screening for patients awaiting CABG surgery. ObjectivesThis retrospective study aimed to determine the association between laboratory based-frailty and patient health outcomes after CABG surgery. MethodsWe evaluated 896 patients who underwent on-pump or off-pump CABG surgery between August 1, 2015 and July 31, 2020 at a tertiary hospital. The frailty index-laboratory (FI-LAB), which comprises 32 laboratory parameters and vital signs, was used for frailty assessment. ResultsThe patients were divided into three groups according to their preoperative FI-LAB level as low (FI-LAB <0.25, 23.0%), moderate (FI-LAB ≥0.25 to ≤0.4, 54.9%), and high (FI-LAB>0.4, 22.1%) frailty groups. In the confounder-adjusted analysis, the lengths of hospital stay and intensive care unit stay were longer by 2.20 days (p=.023) and by 0.89 days (p=.009), respectively, in the high frailty group than those in the low frailty group. The odds ratio for 30-day readmission was also 2.58 times higher in the high frailty group than that in the low frailty group. ConclusionA high preoperative FI-LAB score indicates increasing risks of adverse postoperative outcomes among CABG surgery patients. FI-LAB has potential strengths to capture the need for a more thorough frailty assessment for cardiac surgery patients.

The Effect of Single Vessel Off-pump and On-pump Coronary Artery Surgery on Postoperative Complications

Giriş ve amaç: Günümüzde koroner bypass ameliyatları hala yaygın olarak on-pump CABG ve off-pump CABG tekniği ile yapılmaktadır. Bu retrospektif klinik çalışmada her iki cerrahi yöntemin kısa ve uzun dönem komplikasyonlarını araştırdık.&#x0D; Gereç ve Yöntemler: Bu çalışmaya 2011-2015 yılları arasında kliniğimizde Syntax skorlamasına göre izole tek damar koroner arter hastalığı olan; on-pump (Grup 1) ve off-pump (Grup 2) koroner arter cerrahisi geçiren toplam 43 hasta dahil edilmiştir. Bu hastalarda postoperatif erken dönem komplikasyonlar ve bir yıllık majör advers kardiyovasküler ve serebral olaylar karşılaştırılmıştır.&#x0D; Bulgular: Her iki grup arasında demografik verilerde istatistiksel olarak anlamlı fark saptanmadı. Postoperatif komplikasyonlar açısından atrial fibrilasyon off-pump cerrahi yapılan grupta anlamlı olarak daha az saptanmıştır. Yoğun bakımda ve hastanede kalış süreleri, pnömoni, sternal enfeksiyon ve postoperatif drenaj miktarları açısından anlamlı farklılık saptanmamıştır. Operasyon sonrası uzun dönemde majör adverse kardiyovasküler ve serebral olaylar (MACCE) açısından gruplar arasında farklılık saptanmamıştır.&#x0D; Sonuç: Sonuç olarak koroner bypass cerrahisinde uygulanacak yöntemin hastanın risk skorlamasına göre belirlenmesini öneriyoruz.

The Influence of Operation Duration and Ischemic Time of Artificial Circulation on the Structure of Postoperative Complications in Patients after Surgical Treatment of Multivalvular Defects Combined with Coronary Pathology

The aim. To determinate the influence of the duration of artificial circulation and ischemic time on the structure of complications with one-time combined correction of lesions of two or three heart valves and myocardial revascularization and the possibility of their avoidance.&#x0D; Materials and methods. The work is based on a comparative analysis of the results of one-step multivalvular correction combined with coronary artery bypass grafting (CABG) in 93 patients, which was performed at the National Amosov Institute of Cardiovascular Surgery from 2014 to 2021. Depending on the tactical approaches and the sequence of surgical manipulations, the patients were divided into three groups. Group I included patients who underwent heart valve correction first and then CABG with the use of cardioplegia (n = 42), group II patients underwent CABG first and then valve correction with the use of cardioplegia (n = 36), and group III patients underwent off-pump CABG first and then correction of the heart valves (n = 15). The groups differed significantly in terms of ischemic time and artificial circulation.&#x0D; Results. The use of different approaches to achieve high-quality protection of the myocardium during ischemia and to minimize the impact of artificial circulation on the body by improving conditions and reducing ischemic time in the correction of multivalvular lesions and CABG showed significant advantages of the method of off-pump bypass.&#x0D; Conclusions. Correction of combined valvular and coronary pathology in patients with cardioplegic arrest increases the ischemic time above the critical point, which affects the occurrence of specific complications, especially acute heart failure, which significantly worsens the immediate results of surgery. Complications that occurred in the postoperative period in patients with the correction of valvular defects combined with CABG were due to prolonged cardiovascular failure. The technique proposed in the study group with off-pump bypass surgery was more effective than in groups where bypass was performed with the use of cardioplegic cardiac arrest. This technique requires more time to perform and is more technically complex, but can significantly reduce myocardial ischemic time, which, in turn, significantly reduces the incidence of heart failure and postoperative complications.

Invasive and Non-invasive Dynamic Parameters to Predict Fluid Responsiveness After Off-pump Coronary Surgery.

ObjectiveThis study aimed to assess the predictive value of invasive and non-invasive dynamic parameters for evaluation of fluid responsiveness after off-pump coronary artery bypass grafting.MethodsThirty-two adult patients after off-pump coronary surgery were enrolled into a single-center pilot prospective observational study. After arrival to the intensive care unit, all patients received standard fluid challenge test to assess fluid responsiveness. The patients with an increase in cardiac index ≥ 15% after the test were defined as fluid responders. We measured pulse pressure variation using 2 monitoring systems (PPVPiCCO and PPVNK), stroke volume variation, heart–lung interaction index, and plethysmogram variability index before and after standard fluid challenge test.ResultsAfter intensive care unit admission, the absolute values of stroke volume variation, PPVPiCCO, PPVNK, and heart–lung interaction index were significantly higher among fluid responders (P < .05). Response to standard fluid challenge test was predicted by dynamic assessment of PPVPiCCO (area under the curve 0.84), PPVNK (area under the curve 0.71), stroke volume variation (area under the curve 0.77), and heart–lung interaction index (area under the curve 0.77) (P < .05). The plethysmogram variability index value did not demonstrate any predictive ability regarding fluid responsiveness (area under the curve 0.5, P = .1).ConclusionsIn patients after off-pump coronary surgery, both invasive parameters such as pulse pressure and stroke volume variations and non-invasive parameter such as heart–lung interaction index are able to predict fluid responsiveness. Thus, these dynamic parameters can be used to guide fluid therapy during the early postoperative period after off-pump coronary surgery.

Abstract No. : ABS1022: Effect of use of Entropy Monitoring on Consumption of Sevoflurane Inhalational Agent in patients undergoing off-Pump Coronary Artery Bypass Graft Surgery

Background & Aims:Assessing depth of anaesthesia using entropy is resourceful as it allows for accurate hypnotic drug administration and decreased anaesthetic drug consumption. This study was performed to evaluate the effect of entropy monitoring on sevoflurane consumption in patients undergoing off-pump coronary artery bypass graft (OPCABG) Surgery.Methods:60 patients of American Society of Anesthesthesiologists grade II and III between 40-70 years of age, of either sex planned for OPCABG surgery were randomly allocated to two groups. In the control group B, sevoflurane was titrated according to changes in clinical parameters and in the study group A, sevoflurane was titrated to maintain state entropy values between 40-60 accordingly. Response entropy and state entropy values were continuously recorded in both the groups but were displayed on the monitor only in the study group. The entropy values, sevoflurane consumption andrecovery times were compared.Results:Sevoflurane consumption and recovery time were significantly reduced in the study group A than the control group B (p-value <0.001); Sevoflurane consumption was 7.03±0.67 ml/h vs 12.42±0.68 ml/h; recovery time 6.47±0.65 h vs 12.05±1.11 h). Response and state entropy values were lower in the control group than the study group (p < 0.001). Systolic blood pressure during skin incision, sternotomy and at the time of completion of all grafts were significantly lower in study group.Conclusion:Monitoring the depth of anaesthesia using entropy monitoring leads to significant reduction in sevoflurane consumption. Significantly faster recovery rate from surgery could be associated with more accurate hypnotic and analgesic drug administration.

Abstract No. : ABS2957: Efficacy of continuous magnesium infusion in prevention of post- operative atrial Fibrillation in patients undergoing off-Pump Coronary Artery Bypass Graft Surgery

Background & Aims:Postoperative atrial fibrillation (POAF) occurs in 30-50% of patients after coronary artery bypass surgery (CABG). Serum hypomagnesemia is common after cardiac surgeries.The primary objective was to evaluate whether magnesium infusion could reduce the incidence of postoperative atrial fibrillation (POAF) after off pump CABG.Methods:This prospective, singe centre, randomised controlled study was conducted among 100 patients who underwent off-pumpCABG. The participants were classified into two groups: Group (M); study group in which magnesium infusion was started for three days after an initial bolus dose when the patient was received in intensive care unit (ICU) and Group (C); control group was managed with usual care. The target in Group M was to attain a serum magnesium level of 1.5 to 2 mmol/L. Theincidence of POAF was observed in both the groups. A p value < 0.05 was taken as statistically significant.Results:The incidence of POAF was significantly higher in control group (20%) when compared to the study group (2%)(p=0.008). There were no significant changes in vasoactive inotropic scores, length of ICU stay, additional pharmacotherapy and cardioversion needed between both the groups.Conclusion:The study established that continuous magnesium infusion was effective in preventing POAF in patients undergoing off-pump CABGs.

Impact of aspirin on bleeding and blood product usage in off-pump and on-pump coronary artery bypass graft surgery.

Major bleeding is linked to poorer outcomes following cardiac surgery. Current guidelines recommend continuation of aspirin prior to coronary artery by‐pass graft (CABG) but the effect of continuing aspirin in patients with prior indication for aspirin, in particular during off‐pump CABG (OPCABG), has not been systematically assessed. In this study, we analysed the effect of continuing aspirin prior to OPCABG and on‐pump CABG with respect to bleeding and blood product usage. We compared propensity‐matched cohorts of patients who continued aspirin until the day of OPCABG or CABG to controls (no antiplatelet) and to patients discontinuing aspirin 5–7 days prior. Length of hospital stay, 30‐day mortality and thromboembolism rates were similar for both OPCABG and CABG. During OPCABG, aspirin‐continued patients received more intraoperative red cell units compared to controls without difference in bleeding. Aspirin‐continued patients received more blood products perioperatively and bled more than aspirin‐discontinued patients undergoing OPCABG. The only difference during CABG was a small increase in the volume of cells salvaged among aspirin‐continued patients compared to controls. Current guidelines on the continuation of aspirin prior to CABG and OPCABG are safe. Continuation of aspirin prior to OPCABG may result in more bleeding and blood product usage.

Prognostic impact of secondary prevention after coronary artery bypass grafting-insights from the TiCAB trial.

There are disparities in the adherence to guideline-recommended therapies after coronary artery bypass graft (CABG). We therefore sought to evaluate the effect of guideline-adherent medical secondary prevention on 1-year outcome after CABG. Data were taken from the randomized 'Ticagrelor in CABG' trial. From April 2013 until April 2017, patients who underwent CABG were included. For the present analysis, we compared patients who were treated with optimal medical secondary prevention with those where 1 or more of the recommended medications were missing. Follow-up data at 12 months were available in 1807 patients. About half (54%) of them were treated with optimal secondary prevention. All-cause mortality [0.5% vs 3.5%, hazard ratio (HR) 0.14 (0.05-0.37), P < 0.01], cardiovascular mortality [0.1% vs 1.7%, HR 0.06 (0.01-0.46), P = 0.007] and major adverse events [6.5% vs 11.5%, HR 0.54 (0.39-0.74), P < 0.01] were significantly lower in the group with optimal secondary prevention. The multivariable model for the primary end point based on binary concordance to guideline recommended therapy identified 3 independent factors: adherence to guideline recommended therapy [HR 0.55 (0.39-0.78), P < 0.001]; normal renal function [HR 0.99 (0.98-0.99), P = 0.040]; and off-pump surgery [HR 2.06 (1.02-4.18), P = 0.045]. Only every second patient receives optimal secondary prevention after CABG. Guideline adherent secondary prevention therapy is associated with lower mid-term mortality and less adverse cardiovascular events after 12 months.