Background Heparin dosage for anticoagulation during cardiopulmonary bypass (CPB) is commonly calculated based on the patient's body weight. The protamine-heparin ratio used for heparin reversal varies widely among institutions (0.7-1.3?mg protamine/100 IU heparin). Excess protamine may impair coagulation. With an empirically developed algorithm, the HeProCalc program, heparin, and protamine doses are calculated during the procedure. The primary aim was to investigate whether HeProCalc-based dosage of heparin could reduce protamine use compared with traditional dosages. The secondary aim was to investigate whether HeProCalc-based dosage of protamine affected postoperative bleeding. Patients and Methods We consecutively randomized 40 patients into two groups. In the control group, traditional heparin and protamine doses, based on body weight alone, were given. In the treatment group, the HeProCalc program was used, which calculated the initial heparin bolus dose from weight, height, and baseline activated clotting time and the protamine dose at termination of CPB. Results We analyzed the results from 37 patients, after exclusion of three patients. Equal doses of heparin were given in both groups, whereas significantly lower mean doses of protamine were given in the treatment group versus control group (211?±?56 vs. 330?±?61?mg, p?
Cardiac transplantation has become an established part of the therapy of end-stage heart disease. The number of cardiac transplants performed, as well as the number of centers performing them, has increased dramatically in the past 2 years. A paucity of literature on the anesthetic management of patients undergoing cardiac transplantation prompted this survey of 46 United States and Canadian institutions. The report summarizes the perioperative anesthetic management of a total of 1,273 transplant recipients in 34 institutions. Generally, similar anesthetic techniques and agents were used. One notable exception was the percentage of institutions using perioperative pulmonary artery catheter monitoring. As determined from this survey, right ventricular failure remains the leading cause of inability to terminate cardiopulmonary bypass in this patient population. Further, in surveyed institutions, cardiac transplantation expends more physician as well as hospital resources per patient than coronary artery bypass surgery.
Division of Cardiac Surgery, Dallhousie University, Halifax, Nova Scotia, Canada; Department of Community Health and Epidemiology, Dallhousie University, Halifax, Nova Scotia, Canada. Electronic address: firstname.lastname@example.org.
Precursor events are undesirable events that can lead to a subsequent adverse event and have been associated with postoperative mortality. The purpose of the present study was to determine whether precursor events are associated with a composite endpoint of major adverse cardiac events (MACE) (death, acute renal failure, stroke, infection) in a low- to medium-risk coronary artery bypass grafting, valve, and valve plus coronary artery bypass grafting population. These events might be targets for strategies aimed at quality improvement.
The present study was a retrospective cohort design performed at the Queen Elizabeth Health Science Centre. Low- to medium-risk patients who had experienced postoperative MACE were matched 1:1 with patients who had not experienced postoperative MACE. The operative notes, for both groups, were scored by 5 surgeons to determine the frequency of 4 precursor events: bleeding, difficulty weaning from cardiopulmonary bypass, repair or regrafting, and incomplete revascularization or repair. A univariate comparison of =1 precursor events in the matched groups was performed.
A total of 311 MACE patients (98.4%) were matched. The primary outcome occurred more frequently in the MACE group than in the non-MACE group (33% vs 24%; P = .015). The incidence of the individual events of bleeding and difficulty weaning from cardiopulmonary bypass was significantly higher in the MACE group. Those patients with a precursor event in the absence of MACE also appeared to have a greater prevalence of other important postoperative outcomes.
Patients undergoing cardiac surgery who are exposed to intraoperative precursor events were more likely to experience a postoperative MACE. Quality improvement techniques aimed at mitigating the consequences of precursor events might improve the surgical outcomes for cardiac surgical patients.
Despite major advances in biomaterial research and blood conservation, bleeding is still a common complication after cardiopulmonary bypass and cardiac surgery remains a major consumer of blood products. Although the underlying mechanisms for these effects are not fully established, two proposed major etiologies are the hemodilution associated with the use of the heart-lung machine and the impact of reinfusion of shed cardiotomy blood. Therapeutic strategies that primarily encompass the use of devices or technologies to overcome these effects may result in improved clinical outcomes.
To determine the extent to which 1) lipid/leukocyte filtration and centrifugal processing of cardiotomy blood, and 2) modified ultrafiltration (MUF) are currently applied in adult cardiac surgery in Canada.
A questionnaire was mailed to the chief perfusionist at all adult cardiac surgical centers in Canada, addressing details regarding the frequency of use of cardiotomy blood processing and MUF.
All questionnaires (36, 100%) were completed and returned. With regards to cardiotomy blood management, in 21 centers (58%), no specific processing steps were utilized exclusive of the integrated cardiotomy reservoir filter. Of the remaining centers, two (6%) reported using lipid/leukocyte filtration and 15 (42%) reported washing their cardiotomy blood. Three centers (8%) reported using MUF at the end of CPB.
Despite growing concern about the potential detrimental effects of cardiotomy blood, few centers in Canada routinely manage this blood with additional filtration and/or centrifugal processing prior to reinfusion. Similarly, MUF, demonstrated to be effective in the pediatric population, has not seen popular application in adult cardiac surgical practice.
The authors sought to establish whether regional ischemic preconditioning (IP) reduces ischemic reperfusion arrhythmias in patients who undergo off-pump coronary artery bypass grafting (OPCAB).
A controlled, randomized, prospective study.
A university hospital.
Thirty-two patients with left anterior descending coronary artery (LAD) or 2-vessel heart disease (including LAD) who were to undergo OPCAB were randomized into an IP and a control group.
IP was induced by occluding the LAD twice for a 2-minute period followed by 3-minute LAD reperfusion before bypass grafting of the first coronary vessel.
Twenty-four-hour electrocardiography was recorded from the preoperative day to the second postoperative day. The heart rate (HR) was significantly elevated after surgery. Supraventricular extrasystole (SVES) events were similar before and after surgery. The incidence of patients with ventricular extrasystole (VES), supraventricular tachycardia (SVT), atrial fibrillation (AF), and ventricular tachycardia (VT) was significantly increased after the operation. Ventricular arrhythmias occurred mostly during anastomosis and the early reperfusion period and recovered 2 hours after reperfusion. Supraventricular tachyarrhythmias were mostly encountered 24 hours after reperfusion. IP significantly suppressed HR elevation, SVT, and VT after surgery. SVES, VES, and AF episodes were similar between the groups.
Arrhythmia was a common phenomenon during and after an OPCAB procedure. The present IP protocol significantly suppressed HR elevation, the episodes of SVT, and the incidence of VT after surgery.
Recent trials suggest that off-pump coronary artery bypass grafting (OPCAB) reduces the risk of mortality and morbidity compared with conventional coronary artery bypass grafting (CCAB) using cardiopulmonary bypass. Patients with a moderate- to high-risk of complications after CCAB may have additional benefit from OPCAB.
The Best Bypass Surgery Trial is a randomized, single center trial comparing the effects of OPCAB versus CCAB. The inclusion criteria are 3 vessel coronary heart disease affecting one of the marginal arteries, age>54 years, and EuroSCORE>or=5. The primary composite outcome measure consists of all-cause mortality, myocardial infarction, stroke, cardiac arrest, cardiogenic shock, and cardiac revascularization procedure. Follow up involves collection of data of mortality and morbidity via linkage to public registers, quality of life assessment at 3 and 12 months postoperatively and angiographic control at 12 months. The sample size of 330 patients was based on an estimated 75% one-year event free rate of the primary outcome measure in the OPCAB arm and 60% in the control arm with alpha=.05 and beta=.20. Accordingly, the trial will be able to detect an absolute risk reduction of 15% or a relative risk reduction of 37.5%. The median follow-up time is scheduled to 3 years.
Enrollment started in April 2002 and ended March 2006.
The results may have implications on the treatment modality of moderate- to high-risk patients scheduled for coronary artery bypass grafting.
From a budgetary viewpoint, the authors summarize the operative experience of the cardiac surgery program at the Royal Columbian Hospital during its first fiscal year of operation. The program was funded for 250 cardiopulmonary bypass (CPB) procedures: $16,800 per CPB procedure ($4.2 million for the program). The 250 CPB procedures were performed on 248 patients. The 30-day operative mortality was 2%. Thirty patients (12.1%) underwent a second operation for complications or delayed primary closure of the sternum, or both; the complications included aortic prosthetic perivalvular leaks in 2 patients. Eight patients (3.2%) required insertion of an intra-aortic balloon pump preoperatively to stabilize their condition; 10 others (4.0%) required intra-aortic balloon pump insertion at surgery to correct low-cardiac-output syndrome. Blood products were needed for 149 (59.6%) of the 250 CPB procedures. The average hospital stay was 10.4 days for noncoronary procedures and 9.0 days for coronary procedures.
It was analyzed the results of treatment of 152 patients who underwent heart valve surgery. Depending on cardiopulmonary bypass (CPB) duration patients were divided into 4 groups: the 1st--up to 90 min, the 2nd--90-120 min, the 3rd--120-180 min, the 4th--more than 180 min. Severity of initial comorbidities was comparable in all groups. It was revealed that CPB duration effects on intraoperative blood loss, incidence of acute renal failure, encephalopathy, use of inotropic and angiotonic support (p