Cerebral complications of cardiac surgery using cardiopulmonary bypass

The cerebral complications of cardiac surgery using cardiopulmonary bypass are of increasing importance in the practice of cardiac surgery. These complications may be manifested neurologically or neuropsychologically. Cerebral damage may be investigated using pathological, physiological, biochemical or imaging techniques. Attention is currently being focussed on interventions to reduce not only the severe neurological sequelae seen rarely after cardiopulmonary bypass but also to reduce the more widespread neuropsychological or intellectual deficit seen. Interventions may be primarily either in the equipment used such as with the use of membrane as opposed to bubble oxygenators or with new pharmacological agents such as aspartate receptor antagonists.     

Inflammatory response to cardiac surgery: cardiopulmonary bypass versus non-cardiopulmonary bypass surgery

Cardiac surgery has been routinely performed using cardiopulmonary bypass (CPB) ever since its clinical introduction during the 1950s. CPB is, however, associated with an intense inflammatory response because of conversion to laminar flow, blood contact with the artificial bypass surface, cold cardiac ischaemia and hypothermia. The inflammatory reaction can intensify to a systemic inflammatory response syndrome (SIRS) associated with serious morbidity and mortality. Strategies to suppress inflammation had some success but fell short of controlling SIRS. The development of cardiac immobilization techniques allowing complete revascularization has caused a renaissance of coronary artery bypass grafting surgery on the beating heart (OPCAB). This strategy avoids all inflammation caused by CPB and reduces the pro-inflammatory stimulus to sternotomy and the revascularization procedure itself. This review summarises the pathophysiological features of the inflammatory response to CPB, revisits therapeutic anti-inflammatory strategies designed to suppress CPB-induced inflammation and balances the clinical evidence available comparing off-pump and on-pump revascularization.     

Tracheal tube cuff pressure during cardiac surgery using cardiopulmonary bypass

To determine the effects of cardiopulmonary bypass (CPB) ontracheal cuff pressure, we have measured intracuff pressure(ICP) in 29 consecutive patients undergoing cardiac surgerywith CPB. Premedication comprised hyoscine and, after inductionof anaesthesia with diazepam and fentanyl, followed by vecuronium,the trachea was intubated using a Portex Profile tracheal tube.Anaesthesia was maintained with high-dose fentanyl and 100%oxygen. ICP was measured with a transducer and the ICP was adjustedto 20 mm Hg. CPB was used with mild to deep hypothermia andblood-gas tensions were regulated according to alpha-stat (temperatureuncorrected) pH management. Before CPB, ICP was significantlyreduced from the mean baseline value of 20 (SEM 0.2) to 16.7(0.6) mm Hg (P < 0.01). ICP changed significantly duringCPB, decreasing to 8.0 (1.0) mm Hg before rewarming {P <0.01 vs immediately before CPB) and increasing to 17.0 (0.6)mm Hg after the start of rewarming (P < 0.01 vs before rewarming).After CPB, ICP did not differ significantly from that immediatelybefore CPB. We conclude that the decrease in ICP during thehypothermic phase of CPB may protect the tracheal mucosa againsthypotensive ischaemic injury. (Br. J. Anaesth. 1995; 74: 283–286)     

Assessment of extracellular fluid in cardiac surgery using cardiopulmonary bypass

Extracellular fluid (ECF) was assessed before and after the cardiac surgery using cardiopulmonary bypass (CPB), by means of a bioimpedance spectrum analyzer to see volumes of the fluid based on changes of the impedance to various frequencies. Difference between the levels before and after the operation was divided by body weight to study about a % BW. Simultaneously its relation to the lung compliance [tidal volume/(peak inspiratory pressure-end expiratory pressure)] was studied. Mean age of the 18 patients was 59.1 +/- 19 years old. ECF was assessed before to 24 hours after the operation continuously and once more after 48 hours. Mean CPB time was 165 +/- 52 minutes, and aortic cross clamp time was 121 +/- 4 minutes. A remarkable increase of ECF was noted immediately after the operation, which further increased gradually till arriving at the peak 4 hours after the operation (4.52 +/- 1.8% BW). Then it gradually decreased to 0.641 +/- 2.7% BW 48 hours later. Lung compliance measured at the same time showed the lowest level 6 hours after the operation. It was known that the bioimpedance spectrum analysis is a simple and non-invasive method, which enables to monitor the vital stable before and after the operation.     

Port-Access coronary artery bypass grafting: technical considerations and results

BACKGROUND: This study reviews the results of an initial experience with minimally invasive coronary bypass surgery using the Port-Access approach in terms of early outcome and safety. METHODS: Between October 1996 and July 1997 49 Port-Access minimally invasive coronary artery bypass grafting procedures were performed at our institution. The patients' mean age was 59.8 years (range 34 to 82 years). Sixteen patients received single vessel and 37 patients received multivessel bypass grafts. RESULTS: There were no operative deaths and no perioperative myocardial infarctions, neurological deficits, or conversions to sternotomy. Early complications included reoperation due to bleeding in 4 patients, reoperation for a pulmonary embolus in 1 patient, and angioplasty for occlusion of a right coronary artery graft in 2 patients. Postoperative angiograms were obtained in 86% (42/49) of the patients and showed 100% patency for left internal mammary artery to left anterior descending artery grafts and 96% patency for all grafts. CONCLUSIONS: These results demonstrate that Port-Access coronary artery bypass grafting using endovascular techniques for cardiopulmonary bypass and cardioplegic arrest can be performed safely with minimal morbidity and mortality. This technique allows multivessel revascularization on a protected, arrested heart with excellent anastomotic precision and reproducible early graft patency. Expanded use of Port-Access techniques is indicated in patients with multivessel coronary artery disease and the technique should be considered for patients with left anterior descending artery restenosis and patients with complex left anterior descending artery lesions where angioplasty results are suboptimal.     

Port-Access mitral valve surgery: summary of results

BACKGROUND: The purpose of this study was to review the short-term results of an initial experience with minimally invasive cardiac valve surgery using the Port-Access approach in terms of feasibility, safety, and reproducibility. METHODS: Between October 1995 and October 1997, 151 minimally invasive cardiac valve procedures were performed at our institution using the Port-Access approach. The patients' mean age was 58.1 years (range 21 to 91 years) and 50% were male. Aortic valve replacement was performed in 35 (23.2%) patients, mitral valve repair in 56 (37.1%) patients, mitral valve replacement in 36 (23.8%) patients, and complex valve procedures in 24 (15.9%) patients. RESULTS: The operative mortality rate for isolated mitral valve surgery was 1.1% (1/92) and for all mitral valve surgery 3.5% (4/113). The operative mortality rate for isolated aortic valve patients was 5.7% (2/35). For the total group the operating mortality was 4% (6/151). Early complications for mitral valve patients included reoperation for bleeding or tamponade in 5 (4.4%) patients, myocardial infarction in 2 (1.2%) patients, and transient ischemic attack and wound infection in 1 (0.1%) patient each. One patient required reoperation for mitral valve failure that resulted in aortic dissection unrelated to the Endoaortic Clamp catheter and ultimately led to death. Two (5.6%) aortic valve patients required reoperation for bleeding and two (5.6%) required reoperation for tamponade. CONCLUSIONS: Minimally invasive Port-Access techniques can be applied to most patients with valvular heart disease with minimal morbidity and mortality and good postoperative valve function and may be the preferred approach for isolated mitral and aortic valve surgery.     

Extra cardiac Fontan without cardiopulmonary bypass: techniques and early results

Extracardiac Fontan is currently the preferred final palliation for patients with a univentricular heart. The operation is commonly performed on Cardiopulmonary bypass on a beating heart. In this review, we discuss a protocol for successfully performing this operation without cardiopulmonary bypass. The advantages and pitfalls of this technique are briefly discussed.     

Successful weaning from cardiopulmonary bypass after cardiac surgery using inhaled nitric oxide

Two cases of very difficult weaning from cardiopulmonary bypass after cardiac surgery in children with pulmonary hypertension and ventricular dysfunction are reported. Children fail to respond to conventional therapy combining nitrovasodilators and inotropic support and react successfully to combined inhaled nitric oxide (NO) and epinephrine or left atrial infused norepinephrine. Postoperative NO inhalation must be prolonged and no toxicity appears. Pulmonary endothelial function recovers only after several days.     

体外循环下心脏手术肺保护策略

背景 肺损伤是心脏手术体外循环(cardiopulmonary bypass,CPB)的主要并发症之一,肺保护一直是临床、实验研究热点.目的 为CPB下心脏手术肺保护提供参考.内容 就近年来心脏手术CPB期间通气策略和麻醉药物、CPB设备和技术、肺动脉灌注技术、药物干预对肺保护作用的进展进行综述.趋向 CPB下心脏手术...     

Staged carotid artery stent and cardiac surgery under cardiopulmonary bypass

The presence of carotid disease in patients undergoing cardiac surgery has been known to increase the risk of peri-operative strokes. However, there are some controversies surrounding carotid artery stenting (CAS) in patients undergoing cardiac surgery with carotid disease. We experienced 5 cases of staged carotid artery stent and cardiac surgery under cardiopulmonary bypass. These cases represent 1.7% of the cardiac surgery between August 2006 and June 2009 at our hospital. There were 4 male and 1 female patient whose ages range from 58 to 81 years old (mean 73.0). Two cases were symptomatic and revealed carotid artery stenosis of 50% or more. The remaining 3 asymptomatic cases had 75% or more stenosis. Wallstent RP stents were used in 3 of the cases, and PRECISE stents in the remaining 2. The mean time of carotid angioplasty and stenting was 101 ± 22 minutes. Among the 5 cases, we experienced 2 periprocedural events. One developed bradycardia and cardiac arrest due to severe aortic valve stenosis, which was promptly improved by temporary cardiac pacing. The other experienced transient hemiparesis. The mean period of time between CAS and cardiac surgery was 53 days, with a range of 23 to 78 days. There were no post-operative deaths or strokes. All 5 cardiac operations were performed successfully. Further cooperation among cardiologists, cardiac surgeons and neurosurgeons is suggested for more careful circulatory assessment during CAS in patients with severe cardiac disease.     

Anticoagulation with bivalirudin during cardiopulmonary bypass in cardiac surgery

Heparin is the standard agent used for systemic anticoagulation during cardiopulmonary bypass in cardiac operations. Alternatives are needed when patients with heparin-induced thrombocytopenia type II are encountered. We present a patient with a clinical picture of heparin-induced thrombocytopenia type II who was effectively anticoagulated with bivalirudin, a direct thrombin inhibitor, during cardiopulmonary bypass for a cardiac operation.     

Conscious cardiac surgery with cardiopulmonary bypass using thoracic epidural anesthesia without endotracheal general anesthesia

OBJECTIVE: The purpose of this study was to evaluate the feasibility of thoracic epidural anesthesia as an alternative technique to general anesthesia in patients undergoing cardiac surgery under cardiopulmonary bypass. DESIGN: A prospective study. SETTING: Tertiary referral heart hospital. PARTICIPANTS: Eleven patients underwent cardiac surgical procedures requiring cardiopulmonary bypass under thoracic epidural anesthesia from February to April 2004. INTERVENTIONS: An epidural catheter was inserted at C7 to T2 intervertebral space on the day before the operation. Subsequently, cardiac surgery was performed using cardiopulmonary bypass. MEASUREMENTS AND RESULTS: The midsternotomy approach was used in all the patients. Anticoagulation was achieved with 300 units/kg of heparin. Under normothermic cardiopulmonary bypass, 6 patients underwent closure of atrial septal defect, 3 underwent valve replacements, and 2 underwent coronary artery bypass surgery combined with valve replacements. Soon after establishing cardiopulmonary bypass, all but 1 patient developed apnea, which was reversed after termination of cardiopulmonary bypass. The mean cardiopulmonary bypass time was 102 +/- 28 minutes, the aortic cross-clamp time was 58 +/- 28 minutes, and the total duration of surgery was 229 +/- 64 minutes. There was no mortality or morbidity in this series. CONCLUSION: Cardiac surgical procedures requiring cardiopulmonary bypass may be performed under thoracic epidural anesthesia, without endotracheal general anesthesia.     

Cold agglutinins in cardiac surgery: management of myocardial protection and cardiopulmonary bypass

Cold agglutinins are of unique relevance in cardiac surgery because of the use of hypothermic cardiopulmonary bypass (CPB). Immunoglobulin M autoantibodies to red blood cells, which activate at varying levels of hypothermia, can cause catastrophic hemagglutination, microvascular thrombosis, or hemolysis. Management of CPB and myocardial protection requires individualized planning. We describe a case of aortic valve replacement in a patient with high titre cold agglutinins and a high thermal amplitude for antibody activation. Normothermic CPB and continuous warm blood cardioplegia were successfully used.     

心肺转流心脏手术术后谵妄的预防

术后谵妄是手术后常见的神经系统并发症,表现为急性发作的注意力不集中、思维混乱和意识水平的改变等.心肺转流心脏手术患者的术后谵妄发生率明显高于其他类型手术,严重影响患者术后恢复和生存质量.尽管不能完全避免术后谵妄的发生,但有效的预防措施可以明显降低心肺转流心脏手术患者术后谵妄的发生率.本文章回顾近年来国内外术后谵妄的相关...     

Renal function changes after elective cardiac surgery with cardiopulmonary bypass

Cardiac surgery can either induce acute renal failure or improve GFR by improving the cardiac performance. In order to study renal function changes after elective cardiac surgery (CS) with cardiopulmonary bypass (CPBP), 21 patients undergoing valvular CS (VCS) or coronary artery bypass (CAB) were prospectively evaluated in three time periods: before, 24 hours after surgery and 48 hours after surgery. Patients were divided in 2 groups according to the GFR percent change in comparison to the baseline value found 24 hours after CS (deltaGFR24): Group 1, deltaGFR24 decrease higher than 20% (n = 11) and Group 2, deltaGFR24 decrease < or = 20% or deltaGFR24 increase (n = 10). In Group 1, 73% of the patients underwent VCS (p = 0.05 vs. Group 2) and all of them had previous VCS in sharp contrast with Group 2, where none of the patients had previous CS (p = 0.006). Patients in Group I required more volume replacement than Group 2 during the first 24 hours after CS: 2,699+/-704 mL versus 217+/-603 mL respectively, p = 0.019. Despite similar baseline GFR, Group 1 presented lower GFR 24 hours after CS when compared to Group 2 (39+/-5 versus 75+/-8 mL/(min x 1.73m2), p = 0.001) and a significantly different deltaGFR 48 hours after CS as compared to Group 2 (-21+/-11 versus +88+/-36%, p<0.01). Baseline sodium fractional excretion (FENa) in Group 1 was lower than in Group 2 (0.27+/-0.04 versus 0.70+/-0.12%, p = 0.01). No changes were observed after CS in urinary osmolality (Uosm) and urinary pH (UpH) in both groups. The deltaGFR24 showed positive correlation with baseline FENa (r = 0.44 p = 0.04) and negative correlation with volume balance during the first 24h after CS (r = -0.63, p = 0.007). More patients in Group 1 required nitroprusside than in Group 2 (66% vs. 14%, p = 0.04). Anesthesia time was shorter in Group 1 as compared to Group 2: 323+/-21 vs. 395+/-26 min, p = 0.04. No significant hemolysis occurred during CS in either group. There were no differences in age, gender, CPBP time, need for dopamine and/or dobutamine between the two groups. In conclusion, patients who presented GFR decrease after CS underwent VCS more frequently, had more prevalence of previous CS, presented lower baseline FENa, required more volume infusion and more nitroprusside use. On the other hand, no tubular dysfunction was detected in the early follow-up of CS. These results suggest that the observed renal function changes should be the result of an appropriated renal response to a low effective blood volume. In fact, a low baseline FENa anticipated a GFR decrease in these patients. Consistently, CAB patients that usually improve their cardiac output after surgery showed a clear GFR improvement.     

Anemia-associated acute kidney injury after cardiac surgery with cardiopulmonary bypass

Objective To investigate the incidence and to evaluate the risk factors of acute kidney injury (AKI) following cardiac surgery with cardiopulmonary bypass (CPB) at general hospitals. Methods A retrospective cohort database study was conducted, involving 233 patients who were scheduled to heart valve surgery or coronary artery bypass grafting (CABG) with CPB technique. Logistic regression was used to screen out the risk factors of AKI after the surgery. Results The study population, with an average age of 57±12 years (age 21 to 83) were investigated, there were 54(23.2%) diabetes patients, 105 (45.1%) hypertension patients, 21 (9%) chronic kidney disease (CKD) patients, and 51 (21.9%) anemia patients. Overall incidence of AKI was 32.2%. The Analysis Result indicates that preoperative CKD, anemia, hypoalbuminemia, left ventricular ejection fraction, intraoperative aortic block time, minimum mean arterial pressure, perioperative infection, and application of vancomycin are risk factors associated with postoperative AKI. Multiariable Logistic regression suggests that basic CKD (OR=9.498, P=0.001), anemia (OR=3.150, P=0.021), the LVEF before surgery (OR=1.733, P=0.045), intraoperative aortic block time (OR=2.227, P=0.026), and white blood cell (OR=3.357, P=0.032) were the independent risk factors of AKI. Conclusions AKI is a common complication following cardiac surgery with CPB. The patients with preoperative renal insufficiency, anemia, long intraoperative aortic block time and higher perioperative white blood cell count are subjected to a higher incidence of AKI. Alleviating patients’ anemia and reducing artery block of extracorporeal circulation time therefore might be potential means to mitigate the risks of AKI after cardiac surgery.