Postoperative complications of coronary artery bypass grafting surgery

Coronary artery bypass grafting (CABG) surgery continues to be an effective and well-used intervention for coronary artery disease. Older patients and those with sicker hearts will become the norm. In spite of increased risk for patients undergoing CABG, overall mortality rates have decreased. Nursing contributions to these improved outcomes cannot be overestimated. Continued understanding and appreciation of these complications will be necessary to effectively care for patients and create optimal outcomes.     

Altered protein metabolism following coronary artery bypass graft (CABG) surgery

The aim of the present study was to investigate the acute effect of CABG (coronary artery bypass graft) surgery on the rates of synthesis of muscle protein, the positive acute-phase protein fibrinogen and the negative acute-phase protein albumin. Synthesis rates of muscle protein, fibrinogen and albumin were measured simultaneously before and 4 h after the end of surgery from the incorporation of L-[(2)H(5)]phenylalanine (given at 43 mg/kg of body weight) in 12 patients undergoing CABG surgery. Surgery was performed either with the use of extracorporeal circulation with cardiopulmonary bypass (on-pump; n=5) or with the beating heart procedure without cardiopulmonary bypass (off-pump; n=7). Post-surgical muscle protein fractional synthesis rates were decreased by 36+/-6.5% compared with pre-surgical values (1.59+/-0.10 compared with 0.97+/-0.08%/day respectively; P<0.001). In contrast, the synthesis rates of both fibrinogen (36+/-4 compared with 100+/-11 mg.day(-1).kg(-1) of body weight; P<0.0001) and albumin (123+/-12 compared with 178+/-19 mg.day(-1).kg(-1) of body weight; P<0.001) were both significantly increased after surgery. No significant differences were found between surgery performed with or without cardiopulmonary bypass. In conclusion, the results demonstrate that CABG surgery has a profound effect on protein metabolism, with a differential response of protein synthesis in muscle and liver.     

Adherence to risk-factor instructions one year following coronary artery bypass surgery

A convenience sample (n = 60) of two comparable groups of cardiac bypass patients was studied to assess the effectiveness of a structured teaching guide used by nurses in educating patients and families about normal postoperative recovery and risk-factor modification. One group was educated by an unstructured method, and the other group received structured teaching with the use of a written guide developed by nurses experienced in open-heart recovery. Both groups had higher total knowledge scores postoperatively than preoperatively. To assess whether the type of teaching had affected changes in behavior, a six-week postoperative health interview was conducted, and a follow-up questionnaire was mailed at one year.     

Use of tissue Doppler imaging following coronary artery bypass surgery

This study assessed the effect of coronary artery bypass grafting (CABG) on myocardial systolic functions using tissue Doppler imaging (TDI). Fourteen patients (three women and 11 men) who had undergone isolated coronary bypass surgery were included in the study. Their mean age was 61 +/- 8 years. TDI systolic velocity measures were obtained from four different sites on the left ventricular wall (anterior, septal, lateral and inferior) at the papillary muscle level in the parasternal short axis view before CABG, and then at 1 and 6 weeks post-operatively. There were significant increases in the myocardial wall velocities at all left ventricular sites 1 week after CABG. This increase persisted to week 6 after CABG, but the velocities were lower than week 1 values. We conclude that the ischaemic myocardium responded to surgical revascularization with marked increases in myocardial segmental systolic velocities in the early post-operative period.     

Outcomes improvement following minimally invasive direct coronary artery bypass surgery

The most progressive movement in the standardization of MIDCAB has occurred within the past 5 years. Standardization of care and continuous quality improvement are essential to improve outcomes and reduce costs for MIDCAB. At the authors' institution, perioperative clinical outcomes demonstrated no significant differences among a traditional single-vessel CABG and a MIDCAB in myocardial infarction rates, reoperations for bleeding, and cerebrovascular accidents. Differences were found in new-onset atrial fibrillation, extubation in the operating room, required transfusions, length of stay in the critical care unit, and overall length of hospital stay. Optimal perioperative critical care recovery may result from an evidence-based approach in the design and delivery of patient care. Standardized nursing interventions may be designed to improve efficiency and reduce inappropriate variations in perioperative care. Because MIDCAB is a palliative intervention for single-vessel CAD, multifactorial CRF management is a necessary adjunct for the achievement of optimal long-term outcomes. CRFs must be managed to maintain long-term arterial conduit patency rates (e.g., 20 y) and to prevent further progression of CAD in the native coronary arteries for MIDCAB patients. Nurse-managed, physician-directed CRF management programs are the avenue to provide such services. The reported clinical outcomes are appropriate variables to track for continuous quality improvement. These clinical outcomes are meaningful, measurable, and appropriate for evaluating the effectiveness of care but do not address quality of life, patient satisfaction, and efficacy of pain management. Nursing care must continue to evolve as more data become available.     

Cardiac troponin I concentrations, but not electrocardiographic results, predict an extended hospital stay after coronary artery bypass graft surgery

BACKGROUND: Cardiac damage in coronary artery graft (CABG) surgery is an important contributor to postoperative cardiac dysfunction and delayed hospital discharge. Currently, no simple method exists for its quantification. METHODS: In a prospective study of 300 patients having routine CABG surgery, we compared cardiac troponin I (cTnI) concentrations at 6 and 24 h after surgery with electrocardiographic (ECG) results as predictors of an extended postoperative stay in the intensive care unit (ICU) and in the hospital. We stratified outcome variables by tertiles of cTnI concentration and studied the significance of differences between outcome variables across tertiles. RESULTS: Multivariate analysis showed that 24-h cTnI is a significant predictor of increased postoperative ICU stay (P = 0.012) and postoperative hospital stay (P = 0.024). For 6-h cTnI, corresponding significance values were P = 0.29 and 0.9. ECG was of no value (P = 0.39 and 0.47). Differences in 24-h cTnI were highly significant, particularly for lowest vs highest tertiles, and allowed stratification of risk into "low" (<10 microg/L), "equivocal" (10-20 microg/L), and "high" (>20 microg/L). CONCLUSIONS: Use of a single 24-h cTnI value to quantify perioperative myocardial damage identifies patients who are at greater risk of extended ICU and hospital stays. This strategy could assist in allocation of patients to different management streams after CABG surgery.     

CRP与FIB在急性冠状动脉综合征中的预测价值

CRP被认为是心血管疾病的独立危险因子被广为重视，在冠状动脉粥样硬化基础上的粥样斑块破裂和微血栓形成是急性心肌梗死的病理基础。FIB在血栓形成中扮演了主要角色，病灶内FIB的代谢、降解与血浆纤维蛋白元存在着必然的联系。本文旨在探讨CRP、FIB在急性冠状动脉综合征(ACS)病人血清中的含量变化及二者的相互关系，以期对心脏事件的发生起到预测作用。     

Quality of life in women following coronary artery bypass graft surgery

The purpose of this study was to determine the effect of coronary artery bypass graft (CABG) surgery on the quality of life of women. Wilson and Cleary's conceptual model of health-related quality of life, which examines five major outcomes (biological variables, symptom status, functional status, general health perceptions, perceived quality of life), was used. Participants included 61 women who provided information by self-report questionnaires before and three months after surgery. The major findings of the study are that women had significantly improved quality of life (p = .004) due to increased satisfaction with health and functioning (p < .001) at three months following CABG surgery. They experienced less angina (p < .001) and shortness of breath (p = .014), although fatigue was unrelieved for the majority of women. Psychological well being improved after surgery for most women (p < .001), with lower anxiety levels (p < .001), greater levels of well being (p = .021), feelings of health (p < .001) and vitality (p = .023). Women reported less use of emotive coping (p = .043), indicating less emotional distress. Nevertheless, 25% of the sample continued to experience severe psychological distress three months after surgery, indicating the need for continued follow-up.     

Omission of aspirin in patients following coronary artery bypass graft surgery

Graft patency is a major factor contributing to the long-term results of coronary artery bypass graft (CABG) surgery. The systematic overview of the Antiplatelet Trialists' Collaboration provides unequivocal evidence that antiplatelet therapy reduces by nearly one-half the odds of coronary graft occlusion following CABG. We retrospectively reviewed patients undergoing CABG during 1993 at the Cardiothoracic Unit, Northern General Hospital, to determine the incidence of, and indications for, aspirin omission following CABG: 462 patients with isolated CABG, 75 patients with a combined CABG and a heart valve procedure and 21 patients with a combined CABG and other non-valve procedure. Thirty-six patients (7.5%) with isolated CABG and CABG combined with a non-valve procedure were not prescribed aspirin. The reasons for aspirin omission were categorized into three groups depending on whether omission was fully justified (group 1), possibly justified (group 2) or unjustified (group 3). Twenty-one patients were in groups 2 and 3, nine of whom were started on aspirin 2–6 weeks after discharge without any ill effect. Forty-two patients were discharged from hospital on a three month course of warfarin. Four months later four patients had died, 24 had changed to aspirin, 10 were still on warfarin and four were on neither drug. Aspirin was sometimes omitted without clear indications. Better provisions for supervision should be made by either the General Practitioner or Hospital Practitioner during the change-over period from oral anticoagulation to antiplatelet therapy in patients on a short course of warfarin.     

Minimally invasive coronary artery bypass surgery

Advances in videoscopic instrumentation and expanding experience with the performance of coronary artery bypass surgery without cardiopulmonary circulatory support is changing the surgical approach to many patients requiring coronary arterial revascularization. We describe the present status of minimally invasive coronary artery bypass surgery being used today.     

置入心血管支架后冠状动脉粥样硬化性心脏病患者的C-反应蛋白变化

背景:心血管支架作为一种异体物质,置入后存在明显的炎症反应过程,主要表现在凝血系统的激活以及炎性标志物血清C-反应蛋白的显著升高.目的:总结探讨支架置入后冠状动脉粥样硬化性心脏病患者炎症反应及C-反应蛋白的变化.方法:应用计算机检索中文期刊全文数据库1990/2009相关文献,检索词为"心血管支架,C-反应蛋白,炎症反应",同时检索PubMed数据库1990/2009相关文献,检索词为"cardiovascular stent on plasma,c-reactive protein".结果与结论:药物涂层支架以金属支架为载体携带药物到达血管损伤局部,使药物在较长的时间内充分释放到血管壁内,减少支架置入后再狭窄的发生.抗炎药物涂层支架主要药物为地塞米松、甲泼尼龙等.抗迁移、抗增生药物涂层支架主要药物为雷帕霉素、紫杉醇、放线菌素D等.支持内膜愈合的药物涂层支架主要药物为雌二醇等.经皮冠状动脉支架置入可诱导和加重局部炎症反应,这对血管内皮的增生与再狭窄有重要影响.反映急性炎症反应的敏感指标如血清C-反应蛋白的浓度对于经皮冠状动脉支架置入后心血管事件的发生有预测价值.冠状动脉内支架置入可显著升高血浆C-反应蛋白水平,所以应充分认识炎症反应及血浆C-反应蛋白、细胞因子的变化对防止心血管支架置入后再狭窄起到的重要作用,及早进行预防及干预,从而减少再狭窄率,提高介入治疗效果.     

Use of genetic programming,logistic regression,and artificial neural nets to predict readmission after coronary artery bypass surgery

As many as 14 % of patients undergoing coronary artery bypass surgery are readmitted within 30 days. Readmission is usually the result of morbidity and may lead to death. The purpose of this study is to develop and compare statistical and genetic programming models to predict readmission. Patients were divided into separate Construction and Validation populations. Using 88 variables, logistic regression, genetic programs, and artificial neural nets were used to develop predictive models. Models were first constructed and tested on the Construction populations, then validated on the Validation population. Areas under the receiver operator characteristic curves (AU ROC) were used to compare the models. Two hundred and two patients (7.6 %) in the 2,644 patient Construction group and 216 (8.0 %) of the 2,711 patient Validation group were re-admitted within 30 days of CABG surgery. Logistic regression predicted readmission with AU ROC = .675 ± .021 in the Construction group. Genetic programs significantly improved the accuracy, AU ROC = .767 ± .001, p < .001). Artificial neural nets were less accurate with AU ROC = 0.597 ± .001 in the Construction group. Predictive accuracy of all three techniques fell in the Validation group. However, the accuracy of genetic programming (AU ROC = .654 ± .001) was still trivially but statistically non-significantly better than that of the logistic regression (AU ROC = .644 ± .020, p = .61). Genetic programming and logistic regression provide alternative methods to predict readmission that are similarly accurate.