Elective Primary Coronary Artery Bypass Research Articles

Single-blind, randomized study comparing clinical equivalence of trulene and prolene polypropylene sutures in elective primary coronary artery bypass graft surgery

BackgroundCoronary artery bypass graft surgery (CABG) is one of the principle therapies for coronary artery disease, as it improves survival rate and quality of life (QoL). Polypropylene suture is commonly used in vascular and cardiac surgeries for anastomosis due to its long-term tensile strength and minimal tissue trauma. This study compared the clinical equivalence of Trulene® (Healthium Medtech Limited) and Prolene® (Ethicon-Johnson & Johnson) polypropylene sutures regarding incidence of myocardial infarction, stroke, renal failure and cardiac death (MACCE) occurring up to 26 weeks’ period post-CABG surgery.MethodsThis multicenter, prospective, two-arm, parallel-group, randomized (1:1), single-blind study (n = 89) was conducted between August 2020 and September 2021. The primary endpoint, post-surgery cumulative incidence of MACCE was evaluated. In addition, anastomotic revision, surgical site infection (SSI), operative time, length of post-operative hospital stay, repeat revascularization, intraoperative suture handling characteristics, time taken to return to work and resume normal day to day activities, subject satisfaction score and QoL, and other adverse events were also recorded.ResultsA total of 80 (89.89%) males and 9 (10.11%) females participated in the study. No incidence of MACCE was recorded in any of the study participants. Non-significant difference was observed in anastomotic revision, SSI, operative time, post-operative hospital stay, revascularization, return to work and normal day-to-day activities, subject satisfaction score and QoL, and intraoperative handling parameters (except ease of passage) between the treatment groups, Trulene® and Prolene®. Compared to screening visit, proportion of subjects with ‘no problems’ for each QoL dimension and the mean visual analogue scale increased with each subsequent follow-up visit.ConclusionTrulene® polypropylene suture is clinically equivalent to Prolene® polypropylene suture and is safe and effective for anastomosis construction in CABG surgery during a routine clinical procedure.Trial registration CTRI Registration No.: CTRI/2020/05/025157 (Registered on: 13/05/2020).

Transfusion thresholds in cardiac surgery: Commentary on Bracey et al., 1999.

Transfusion thresholds in cardiac surgery: Commentary on Bracey et al., 1999.

Predictors of postoperative atrial fibrillation persisting beyond hospital discharge after coronary artery bypass grafting.

Minimal invasive extracorporeal circuits (MiECC) have been associated with a significant reduction in the incidence of postoperative atrial fibrillation (AF). Nevertheless, AF remains one of the most common complications following elective primary coronary artery bypass grafting (CABG). The aim of this study was to identify the predictors of AF persisting beyond the hospital stay in elective primary CABG patients. We conducted a retrospective analysis for the predictors of AF that persisted beyond discharge between all patients who received an elective isolated CABG in our institution between 2009 and 2014. Patients with a positive history for intermittent or persistent AF were excluded from the analysis. Almost all patients were discharged to a rehabilitation facility where they stayed for 3 to 4 weeks postoperatively. At rehab approximately 91% of them received Holter monitoring at least once prior to their discharge. A total of 770 patients were included in the analysis of which 763 patients survived the in-hospital stay. The incidence of AF at hospital discharge was 4.2% (32/763) while that on Holter monitor at Rehab was 1.5% (10/685). Age and the type of extracorporeal circuit (ECC) utilized were the only significant predictors for both AF at discharge (p < 0.01 both) and on Holter monitor in rehab (p < 0.01 and 0.02, respectively). This was also confirmed on multivariate analysis. Our findings show that the benefits of MiECC regarding the incidence of postoperative AF persist beyond hospital discharge. They may thus positively influence the outcomes of patients beyond the early postoperative period.

Frailty syndrome in patients with coronary artery disease

Aim. To assess the prevalence of frailty and describe clinical features of frail patients with stable coronary artery disease (CAD). Methods. 387 patients admitted to the hospital for elective primary coronary artery bypass grafting (CABG) were recruited in the study. Clinical data, demographic data, and the results of the instrumental examinations were collected for each subject. The primary screening of prefrailty and frailty in patients before the surgery was performed using the ’Age is not a hindrance’ questionnaire. The results were processed using the IBM SPSS Statistics 26.0.0 software package. A value of p ≤ 0.050 was considered statistically significant. Results. Frailty was found in 19% of patients with coronary artery disease and multivessel coronary artery disease before open myocardial revascularization, while 58% of patients had prefrailty. The presence of frailty and prefrailty was associated with older and advanced age (p = 0.003), female sex (p = 0.001), type 2 diabetes mellitus (p = 0.006), as well as with comorbidities, including cerebral atherosclerosis (p = 0.020), and heart rhythm disturbances (p = 0.050). Conclusion. The results obtained in this study are consistent with other studies reporting higher levels of comorbidities among frail patients.

Atrial contractility and fibrotic biomarkers are associated with atrial fibrillation after elective coronary artery bypass grafting

ObjectiveNew-onset postoperative atrial fibrillation is common after cardiac surgery. Less has been reported about the relationship among fibrosis, inflammation, calcium-induced left atrial and right atrial contractile forces, and postoperative atrial fibrillation. We sought to identify predictors of postoperative atrial fibrillation. MethodsFrom August 2016 to February 2018, we evaluated 229 patients who had preoperative sinus rhythm before elective primary coronary artery bypass grafting. Of 229 patients, 191 maintained sinus rhythm postoperatively, whereas 38 patients developed atrial fibrillation. Preoperative tissue inhibitor of metalloproteinase-1, pentraxin-3, matrix metallopeptidase-9, galectin-3, high-sensitivity C-reactive protein, growth differentiation factor 15, and transforming growth factor-ß were measured. Clinical and echocardiographic findings (tricuspid annular plane systolic excursion for right heart function) and calcium-induced force measurements from left atrial and right atrial–derived skinned myocardial fibers were recorded. ResultsPatients with atrial fibrillation were older (P = .001), had enlarged left atrial (P = .0001) and right atrial areas (P = .0001), and had decreased tricuspid annular plane systolic excursion (P = .001). Levels of matrix metallopeptidase-9 and pentraxin-3 were decreased (P < .05), whereas growth differentiation factor 15 was increased (P = .001). We detected lower left atrial force values at calcium-induced force measurements 5.5 (P < .05), 5.4 (P < .01), and 5.3 to 4.52 (P = .0001) and right atrial force values at calcium-induced force measurements 5.0 to 4.52 (P < .05) in patients with postoperative atrial fibrillation. Multivariable analysis showed that advanced age (P = .033), decreased left atrial force value at calcium-induced force measurement of 5.5 (P = .033), enlarged left atrial (P = .013) and right atrial (P = .081) areas, and reduced tricuspid annular plane systolic excursion (P = .010) independently predicted postoperative atrial fibrillation. ConclusionsAdvanced age, decreased left atrial force value at calcium-induced force measurement of 5.5, enlarged left atrial and right atrial areas, and reduced tricuspid annular plane systolic excursion were identified as independent predictors for postoperative atrial fibrillation.

Effect of low-dose dexamethasone on extra vascular lung water in patients following on-pump elective primary coronary artery bypass graft surgery.

Background:The primary objective was to compare the effect of a low-dose dexamethasone as against a saline placebo on extravascular lung water index (EVLWI) in patients undergoing elective primary coronary artery bypass surgery. The secondary endpoints were to assess the effect of dexamethasone on other volumetric parameters (pulmonary vascular permeability index, global end diastolic volume index, and intrathoracic blood volume index), Vasoactive Inotrope Scores, hemodynamic parameters and serum osmolality in both groups.Settings and Design:Prospective observational study performed at a single tertiary cardiac care center.Materials and Methods:Twenty patients were randomized to receive either dexamethasone (steroid group, n = 10) or placebo (nonsteroid group, n = 10) twice before the institution of cardiopulmonary bypass (CPB). EVLWI and other volumetric parameters were obtained with the help of VolumeView™ Combo Kit connected to EV 1000 clinical platform at predetermined intervals. Hemodynamic parameters, vasoactive-inotropic Scores, hematocrit values were recorded at the predetermined time intervals. Baseline and 1st postoperative day serum osmolality values were also obtained.Results:The two groups were evenly matched in terms of demographic and CPB data. Intra- and inter-group comparison of the baseline EVLWI including other volumetric and hemodynamic parameters with those recorded at subsequent intervals revealed no statistical difference and was similar. Generalized estimating equation model was obtained to compare the changes between the groups over the entire study period which showed that on an average the changes between the steroid and nonsteroid group in terms of all volumetric parameters were not statistically significant.Conclusions:There were no beneficial effects of low-dose dexamethasone on EVLWI or other volumetric parameters in patients subjected to on-pump primary coronary bypass surgery. Hemodynamic parameters were also not affected. Probably, the advanced hemodynamic monitoring aided in optimal fluid management in the nonsteroidal group impacting EVLW accumulation.

D-dimer is associated with arterial and venous coronary artery bypass graft occlusion

ObjectiveIn this observational prospective study, we assessed the role of clinical variables and circulating biomarkers in graft occlusion at 18 months to identify a signature for graft occlusion. MethodsA total of 330 patients undergoing primary elective coronary artery bypass grafting were enrolled. Blood collection for biomarker assessment was performed before surgery and discharge. Patients were then scheduled to undergo coronary computed tomography angiography at 18 months follow-up, and 179 patients underwent coronary computed tomography angiography 18 ± 2 months postoperatively. ResultsThere were 46 of 503 (9.1%) occluded grafts; of these, 29 (63%) were venous and 17 (37%) were arterial grafts; overall, 43 of 179 patients (24%) had at least 1 occluded graft. Logistic mixed effects model assessing independent factors associated with graft occlusion identified that lower D-dimer levels at baseline (odds ratio [OR], 2.58; 95% confidence interval [CI], 1.36-4.89; P = .00) and total protein content at discharge (OR, 1.09; 95% CI, 1.01-1.19; P = .028) were related to overall graft occlusion at follow-up, along with an arterial graft other than the left internal thoracic artery (OR, 2.92; 95% CI, 1.24-6.9; P = .078); moreover, a venous graft emerged was possibly associated with graft occlusion (OR, 1.51; 95% CI, 0.95-2.39; P = .078). By separately analyzing saphenous vein and arterial grafts, D-dimer levels (OR, 2.67; 95% CI, 1.15-6.2; P = .022 and OR, 2.5; 95% CI, 1.01-7.0; P = .05 for venous and arterial graft, respectively) were still associated with arterial and venous graft occlusion at follow-up. ConclusionsWe identified D-dimer as a biomarker associated with arterial and venous grafts occlusion. This may help stratify patients at risk of graft failure and identify new molecular targets to prevent this complication.

Evaluation of the hemostatic potential at coronary artery bypass surgery during long-term aspirin therapy

To estimate thrombin generation test parameters in patients with coronary heart disease during coronary artery bypass surgery under extracorporeal circulation after transfusion of donor platelet concentrates during long-term therapy with acetylsalicylic acid (ASA). A total of 148 patients with coronary heart disease who had undergone elective primary coronary artery bypass surgery under extracorporeal circulation during preserved therapy with ASA (75-100 mg/day) were examined. According to donor platelet concentrate transfusion, all the patients were divided into 2 groups: 1) 76 patients undergoing donor platelet transfusion and 2) 72 without this procedure. A control group consisted of 20 apparently healthy individuals. At the pre-, intra-, and early postoperative stages, the investigators evaluated the following thrombin generation test parameters: lag time (min); peak thrombin concentration (nM/l); time to peak (min); the area under the thrombin generation curve (nM), and thrombin generation rate (nM/min). During long-term ASA therapy, the patients were found to have an activated endogenous thrombin potential in the pre- and intraoperative periods, as evidenced by the high peak concentration of thrombin and the increased rate of its generation. At the same time, the time of prothrombinase complex activation and that of thrombin generation were longer than those in the control group. In the early postoperative period, the patients who had not been transfused with platelet concentrates with a further increase in the temporal parameters, showed a decreased hemostatic potential, reaching the control level, whereas donor platelet transfusion stimulated endogenous thrombin generation: the time to initiate clotting and that to reach the peak were shorter; in this case, the thrombin generation rate and concentrations increased, but the preoperative level was not reached. No perioperative (hemorrhagic or thrombotic ischemic) events were noted in the examined groups. The hemostatic potential was preserved in patients receiving long-term therapy for ASA. Taking into account laboratory and clinical findings, platelet concentrate transfusions are unnecessary for preventive purposes. The appropriateness of donor platelet transfusion should be strictly individually approached with regard to the laboratory parameters of the thrombin generation test, by minimizing the risk of perioperative ischemic and hemorrhagic events in each specific patient.

Efficacy of Parasternal Injection of Bupivacaine on Postopeartive Pain for Early Extubation in Patients Undergoing Coronary Artery Bypass Surgery

Objectives: The aim of this study was to determine the efficacy of parasternal injection of Bupivacaine on postoperative pain for early extubation in patients undergoing coronary artery bypass grafting. Material and methods: Patients admitted throughout patient department for elective primary coronary artery bypass surgery into the surgical ward were enrolled for the study. A total of 35 patients were randomized into two groups, (Bupivacaine) group 1 13 (37.14%) and (Placebo) group 2 15 (42.85%). Patients were induced with standard anesthetic protocols. Bupivacaine injection 0.5% at 2mg per kg was diluted in 50 mls syringe with normal saline and 50mls of normal saline was used as Placebo. Identical syringes marked with a study number of patient were delivered to the operating theaters. Both the surgeon and the anesthetist were blinded of the content of the solution. At the end of the procedure the injection was infiltrated into the parasternal wound before placing the sternal wires. Patients were assessed in the intensive care unit by the anesthetist for early extubation. At the time of extubation pain intensity was measured with Visual analogue scale system and recorded. Results: A total of 35 patients were selected for the study.28 patients were able to complete the study as [Seven (2.45%) out of 35 patients were excluded from the study secondary to prolonged ventilation 5(14.2%), and reopening 2(5.71%). Mean Visual analogue scale was 1.38±1.19 and 6.13±2.92 in the Bupivacaine and Placebo group respectively with a significant (P<0.001) requirement of rescue pain medication was nil in the Bupivacaine while 8(53.3%) patients were given rescue pain medication in the Placebo group. Mean difference of total ventilation time in the Bupivacaine and Placebo group was Bupivacaine - 5.8±1.3 and Placebo - 122±2.8 hrs, which was statistically significant (p=0.002). Mean Partial oxygen pressure was found 208.23±42.57 and 126.40±23.15 in the Bupivacaine and Placebo groups respectively which was a significant value (P<0.001). Conclusion: We conclude that parasternal wound infiltration of long acting local anesthetic Bupivacaine is an effective method of pain control after sternotomy. It facilitates early extubation with significant improvements in oxygenation and Visual Analogue Scale scales.

A prospective randomized trial of endoscopic versus open saphenous vein harvesting technique for coronary artery bypass graft surgery

The great saphenous vein harvested with a traditional open technique often results in leg wound complications. An endoscopic harvesting technique may decrease incidence of these complications. Fifty consecutive patients having elective primary coronary artery bypass surgery were prospectively and randomly assigned to either endoscopic great saphenous vein harvesting (EVH—group A) or open great saphenous vein harvesting (OVH—group B). Both groups were demographically similar and received identical management. Leg wound healing was evaluated at discharge, 1 week, 1 month and 6 months for evidence of complications. The patient in endoscopic vein harvesting group had increased harvest time and an insignificant increase in vein injuries at the time of harvesting but decreased incision closure times when compared with traditional longitudinal open vein harvesting. Conversion from endoscopy to a traditional longitudinal open vein harvest occurred in 5 % of patients. Leg wound complications were significantly reduced postoperatively in the endoscopic vein harvesting group in comparison with the open vein harvesting group. Histological evaluation of structural integrity of vein samples shows that there is no significant difference between both the groups. No patient was readmitted to the hospital for leg wound complications in either group. EVH is a safe, reliable method for saphenous vein harvesting. The best indication for EVH may be in patients who are in increased risk for wound infection and in whom cosmetics is a major concern.

Cell salvage during coronary artery bypass surgery and allogenic blood exposure.

Our primary aim was to assess the impact of intraoperative cell saver usage on patient exposure to allogenic blood transfusion during elective coronary artery bypass. The secondary endpoint was the impact of cell savage on the units of blood and blood products transfused perioperatively. A prospective observational cohort study with a historical cohort as a control group was performed in a single tertiary care center. One hundred and twenty-four patients undergoing primary on-pump coronary artery bypass grafting were included. Intraoperative cell salvage was performed in 60 patients (study group) but not in the control group (n = 64). Transfusion data, intensive care unit stay, hospital stay, and postoperative complications were evaluated in the cell saver and control groups. The number of patients exposed to allogenic red blood cell transfusion was significantly less in the study group (55% vs. 82.8%; p = 0.001) and the units per patient was also less in the study group (1.10 ± 1.7 vs. 2.25 ± 2.289 units; p = 0.002). However, there was no significant difference in terms of units of purified plasma fraction, platelets, or cryoprecipitate transfused. Intensive care unit stay, total hospital stay, number of reexplorations, complications, readmissions, and 28-day mortality were similar in both groups. Intraoperative cell salvage with a cell saver in patients undergoing primary elective coronary artery bypass decreases the proportion of patients exposed to allogenic red cell transfusions and the number of units of red blood cells transfused.

Early goal-directed therapy based on endotracheal bioimpedance cardiography: a prospective, randomized controlled study in coronary surgery.

The objective was to compare the impact of an early goal-directed hemodynamic therapy based on cardiac output monitoring (Endotracheal Cardiac Output Monitor, ECOM) with a standard of care on postoperative outcome following coronary surgery. This prospective, controlled, parallel-arm trial randomized 100 elective primary coronary artery bypass grafting patients to a study group (ECOM; n = 50) or a control group (control; n = 50). In the ECOM group, hemodynamic therapy was guided by respiratory stroke volume variation and cardiac index given by the ECOM system. A standard of care was used in the control. Goal-directed therapy was started immediately after induction of anesthesia and continued until arrival in the intensive care unit (ICU). The primary endpoint was the time when patients fulfilled discharge criteria from hospital (possible hospital discharge). Secondary endpoints were the hospital discharge, the time to reach extubation, the length of stay in ICU, the number of major adverse cardiac events, and in-hospital mortality. Patients in the ECOM group received more often fluid loading and dobutamine. The time to reach extubation was reduced in the ECOM group: 510 min [360-1,110] versus 570 min [320-1,520], P = 0.005. No significant differences were found between both groups for possible hospital discharge [Hazard Ratio = 0.96 (95 % CI 0.64-1.45)] and hospital discharge [Hazard Ratio = 1.20 (95 % CI 0.79-1.81)]. A mini-invasive early goal-directed hemodynamic therapy based on ECOM can reduce the time to reach extubation but fails to significantly reduce the length of stay in hospital and the rate of major cardiac morbidity.

Significance of preoperative total lymphocyte count as a prognostic criterion in adult cardiac surgery.

Background:Evaluation of operational risk is a consequential goal in perioperative management of patients in cardiac surgery. Preoperative total lymphocyte count (PTLC) is a prognostic criterion of adverse major cardiovascular outcomes.Objectives:The purpose of this study was to investigate the prognostic value of PTLC as an independent predictor of postoperative morbidity and mortality in cardiac surgery.Patients and Methods:Of 1604 patients scheduled for cardiac surgery between September, 2012 and March, 2013, a total of 1171 consecutive patients underwent elective primary valvular heart surgery and coronary artery bypass grafting. The patients were divided to three groups according to their PTLCs. The baseline characteristics and postoperative mortality and morbidity of the patients as well as the intensive care unit (ICU) stay according to the PTLCs were recorded and analyzed. The only inclusion criterion was a preoperative complete blood count. Exclusion criteria included: ages under 18 or over 80 years old, emergency surgery, adult patients with congenital heart disease and previous open heart surgery, and patients with any bacterial or viral infection during two weeks before the surgery. Protocol of anesthetic medications was used in all the patients similarly and according to standard. All the patients were admitted to the ICU after the surgery.Results:A PTLC < 1500 cells/µL was associated with significantly high mortality and morbidity (P = 0.0001). In-hospital mortality and major composite morbidity were 9.65% and 28.4%, respectively. Low PTLC was associated with more frequent need for inotropic and intra-aortic balloon pump (IABP) support (P < 0.001), dialysis-dependent acute renal failure (P = 0.0001), postoperative superficial wound infections (P = 0.0001) and prolong ICU stay (P = 0.0001).Conclusions:Our study results showed that low PTLC was an independent, valuable prognostic criterion, with high sensitivity and specificity for evaluation of postoperative morbidity and mortality in cardiac surgery.

Doxycycline Reduces Cardiac Matrix Metalloproteinase-2 Activity but Does not Ameliorate Myocardial Dysfunction During Reperfusion in Coronary Artery Bypass Patients Undergoing Cardiopulmonary Bypass

Matrix metalloproteinase-2 proteolyzes intracellular proteins in the heart and induces acute myocardial contractile dysfunction in ischemia-reperfusion injury. Doxycycline, a matrix metalloproteinase inhibitor, prevented matrix metalloproteinase-2-induced troponin I cleavage in rat hearts and improved contractile function following ischemia-reperfusion. In patients undergoing coronary artery bypass graft surgery with cardiopulmonary bypass, increased atrial matrix metalloproteinase-2 activity was inversely correlated with cardiac mechanical function at 3 hours reperfusion. We performed a study in patients with coronary artery disease undergoing primary elective coronary artery bypass graft surgery with cardiopulmonary bypass to determine whether doxycycline reduces cardiac mechanical dysfunction, matrix metalloproteinase activity, and troponin I degradation after reperfusion. Randomized, double-blinded, placebo-controlled study. University of Alberta Hospital. Forty-two patients with coronary artery disease undergoing coronary artery bypass graft surgery with cardiopulmonary bypass. Patients were randomized to receive either oral administration of 20 mg of doxycycline or matching placebo pill twice a day at least 2 days prior to surgery, on the day of surgery, and for the first 3 postoperative days. Left ventricular stroke work index was examined prior to cardiopulmonary bypass and at 24 hours reperfusion. Right atrial biopsies were collected before cardiopulmonary bypass and 10 minutes after aortic cross-clamp release to determine matrix metalloproteinase-2 activity and troponin I level. Blood was collected to determine matrix metalloproteinase activity and interleukin-6, C-reactive protein, and troponin I levels. Cardiac 72-kDa matrix metalloproteinase-2 activity was lower upon reperfusion in biopsies from the doxycycline group (p = 0.01), and the increase of matrix metalloproteinase-2 activity in the placebo group due to reperfusion did not appear in the doxycycline group (p = 0.05). Doxycycline, however, did not ameliorate cardiac mechanical dysfunction following reperfusion or the cardiopulmonary bypass-coronary artery bypass graft-induced increased plasma matrix metalloproteinase-9, interleukin-6, and C-reactive protein levels. Cardiopulmonary bypass-coronary artery bypass graft or doxycycline did not change tissue or plasma troponin I levels at 10 minutes reperfusion. Although doxycycline did not improve myocardial stunning following coronary artery bypass graft surgery with cardiopulmonary bypass, it reduced cardiac matrix metalloproteinase-2 activity in these patients. A larger trial and/or higher dose of doxycycline may yet be warranted.

Distal anastomotic patency of the Cardica C-PORT® xA system versus the hand-sewn technique: a prospective randomized controlled study in patients undergoing coronary artery bypass grafting†

The C-Port® Distal Anastomosis Systems (Cardica, Inc., Redwood City, CA, USA) demonstrated favourable results in feasibility trials. However, distal vein anastomoses created with the C-Port® or C-Port xA® system have never been compared with hand-sewn distal vein anastomoses. The objective of this study was to compare distal end-to-side anastomoses facilitated with the C-Port xA® System with the traditional hand-sewn method. This single-centre prospective randomized controlled study comprised 71 patients (device group n = 35, control group n = 36) who underwent primary elective coronary artery bypass grafting between June 2008 and April 2011. The primary study end-point was 12-month distal anastomotic patency, which was assessed with prospective ECG-gated 256-multislice computed tomographic coronary angiography using a step-and-shoot scanning protocol. For the primary end-point, a per-protocol analysis was used. In the device group, four (11%) anastomoses were converted to hand-sewn anastomoses, and additional stitches to achieve haemostasis were necessary in 22 (76%) patients. There was no hospital mortality in either group. During the 12-month follow-up, a single death occurred in the Device group and was unrelated to the device. Twenty-nine patients in the device group and 32 in the control group completed 12-month CT coronary angiography. The overall patency of 160 studied distal vein graft anastomoses was 93%. Comparison of the end-to-side target anastomosis showed 12-month patencies of 86 and 88% in the device group and the control group, respectively. According to these preliminary results and despite the limited number of patients, the use of the C-Port xA® System is safe enough to perform distal end-to-side vein graft anastomosis, with respect to 12-month end-to-side distal venous anastomotic patency. Although there are some technical challenges with this device, the incidence of complications is comparable to the traditional hand-sewn technique.

Efforts to Change Transfusion Practice and Reduce Transfusion Rates Are Effective in Coronary Artery Bypass Surgery

Efforts to decrease allogeneic blood transfusion and avoid unnecessary transfusions in cardiac surgery are important because transfusions are associated with increased postoperative morbidity and mortality. The purpose of the present study was to evaluate the long-term effects of multidisciplinary efforts to reduce allogeneic blood transfusion rates and avoid unnecessary red blood cell (RBC) transfusions in primary elective coronary artery bypass graft (CABG) surgery. A retrospective observational study. A single center study in a university-affiliated hospital. A total of 450 patients undergoing primary elective CABG surgery during 2004, 2008, or 2010. The application of systematic multimodal perioperative blood-sparing techniques and interventions directed to change transfusion behaviors. The results from an audit on transfusion practices in 2004 were compared with similar audits performed in 2008 and 2010 using a before-and-after study design. The patient populations were comparable throughout the years. The median postoperative chest tube bleeding was decreased from 950 mL in 2004 to 750 mL in 2010. The proportion of patients transfused with allogeneic blood products was decreased from 64% to 47%. Overtransfusion with allogeneic RBCs defined as the proportion of patients transfused with RBCs discharged with hemoglobin >7 mmol/L (11.3 g/dL) was reduced from 36% to 16%. Multimodal efforts to change transfusion behaviors and decrease transfusion rates in CABG surgery have persistent effects for several years.

Autotransfusion system or integrated automatic suction device in minimized extracorporeal circulation: influence on coagulation and inflammatory response

To measure surrogate markers of coagulation activation as well as of the systemic inflammatory response in patients undergoing primary elective coronary artery bypass grafting (CABG) using either the so-called Smart suction device or a continuous autotransfusion system (C.A.T.S.®). Fifty-eight patients being operated with a miniaturized circuit (minimal extracorporeal circuit, MECC) were prospectively randomized to using a so-called Smart suction device or a routine continuous autotransfusion system (C.A.T.S.®) for collection of mediastinal shed blood. The coagulation response was measured by thrombin-antithrombin complex (TAT) and D-dimer. The inflammatory response was measured by Interleukin 6 (IL-6) and complement factor 3a (C3a) at three different time points, before surgery, 2h after surgery, as well as 18 h after surgery. No serious adverse cardiovascular event was observed. Serum levels of TAT significantly differed between both groups 2h after surgery (Smart suction 16.12 ± 13.51 μg l⁻¹ vs C.A.T.S® 9.83 ± 7.81 μg l⁻¹, p = 0.040) and returned to baseline values after 18 h in both groups. Serum levels of D-dimer showed a corresponding pattern with a peak 2h after surgery (Smart suction 1115 ± 1231 ng ml⁻¹ vs C.A.T.S.® 507 ± 604 ng ml⁻¹, p = 0.025). IL-6 levels also significantly differed between both groups 2h after surgery (Smart suction 186 ± 306 pg ml⁻¹ vs C.A.T.S.® 82 ± 71 pg ml⁻¹, p = 0.072). No significant changes in serum levels of C3a over time could be observed. Despite no differences in the clinical course of patients with either Smart suction or C.A.T.S.® being observed, surrogate markers of coagulation and inflammation seem to be less pronounced in patients where cardiotomy blood is not being directly reinfused. As such, C.A.T.S.® should be preferred in routine CABG, as long as no extensive volume substitution is anticipated.

A clinical prediction tool to estimate the number of units of red blood cells needed in primary elective coronary artery bypass surgery

Red blood cell (RBC) transfusion is common during cardiac surgical procedures. Empiric crossmatching, without attempting to estimate individual transfusion requirements is typical. We hypothesized that a clinical prediction tool could be developed to estimate the number of units of RBCs needed for coronary artery bypass grafting (CABG) surgery. With institutional review board approval, detailed demographic, risk factor, and transfusion data of primary elective CABG procedures (n=5887) from September 1, 1993, to June 20, 2002, were studied and the data set was divided into development and validation subgroups. Multivariable ordinal logistic regression was used to develop and validate transfusion risk factors, assign them a relative weight, and create a model to stratify patients into groups depending on predicted need for 0, 2, 4, or more than 4 RBC units. The model was compared with current standard practice of crossmatching 4 RBC units in terms of observed blood product usage over the study period. Demographic and transfusion risk factor variables in the development (n=3876) and validation (n=2011) data sets were similar. The predictive value of the model was good for the development and validation groups, with a c-index of 0.79 and 0.78, respectively. Applying the predictive model reduced the number of crossmatches by 30% without underproviding RBC units and increased the percentage of patients crossmatched exactly for the required number of units from 11% to 21%. Predictive factors for RBC transfusion were identified and used to construct a clinical tool to conserve blood bank resources without increasing patient risk.

The inflammatory effect of cardiopulmonary bypass on leukocyte extravasation in vivo

Extravascular trafficking of leukocytes into organs is thought to play a major role in the pathophysiologic mechanisms of the inflammatory response to cardiopulmonary bypass, yet leukocyte extravasation is difficult to study clinically. Here we have tested the hypothesis that leukocyte emigration into skin blisters can provide a way to monitor the inflammatory effect of cardiopulmonary bypass that allows testing of anti-inflammatory interventions (exemplified by aprotinin). Patients undergoing primary elective coronary artery bypass grafting (n = 14) were randomized into 2 equal groups to receive saline infusion during cardiopulmonary bypass (control group) or high-dose aprotinin. Experimental skin blisters (in duplicate) were induced on the forearm by means of topical application of the vesicant cantharidin, and blister fluid was sampled at 5 hours postoperatively. Inflammatory leukocyte subsets in blister fluid were analyzed by means of flow cytometry by using expression of CD11b and CD62L as a phenotypic marker of activation. In the control group of patients, cardiopulmonary bypass surgery triggered a 381% increase in leukocyte extravasation into the skin compared with reference blisters carried out before surgical intervention, with neutrophil (P = .014), monocyte (P = .014), and eosinophil (P = .009) levels all statistically significantly increased. In the aprotinin group there was no statistically significant increase during cardiopulmonary bypass surgery in any inflammatory leukocyte subset. The activation phenotype of extravascular leukocytes was not significantly altered between surgical groups. This study introduces the cantharidin blister technique as a powerful new research tool for analyzing the inflammatory effect of cardiopulmonary bypass in vivo. It has provided detailed molecular insight into the extravascular leukocyte population during cardiopulmonary bypass. Although aprotinin blocked cardiopulmonary bypass-dependent extravasation of leukocytes, there was no change in their CD11b/CD62L activation status. The cantharidin skin test thus represents a novel research tool for evaluating future anti-inflammatory interventions in cardiothoracic surgery.

Predictive models for preoperative transfusion risk evaluation in elective primary cardiac valvular surgery and elective primary off-pump coronary artery bypass surgery

Predictive models for preoperative transfusion risk evaluation in elective primary cardiac valvular surgery and elective primary off-pump coronary artery bypass surgery