Adult respiratory distress syndrome following cardiopulmonary bypass: incidence and prediction

The outcome of adult respiratory distress syndrome complicating cardiopulmonary bypass has changed little in recent years. A retrospective, case-controlled study was designed to assess the incidence of the adult respiratory distress syndrome in these circumstances and the extent to which it could be linked with pre and peri-operative predictive factors. Eleven patients who developed the syndrome out of 840 who underwent cardiopulmonary bypass over a 9 month period were compared with 53 controls matched for sex, operation and surgeon. The incidence of adult respiratory distress syndrome and its mortality were 1.3% and 53% respectively. Significant predictors were a high intra and postoperative intervention score, the total volume of blood pumped during bypass (greater than 300 l) and age (greater than 60 years). These risk factors should alert the clinician to the possibility of severe postoperative pulmonary complications.     

164例法洛四联症的外科治疗

目的总结164例法洛四联症(tetralogyofFallot,TOF)患者手术治疗的经验,探讨手术时机、危险因素和围术期处理等。方法对164例TOF患者行根治手术,其中单纯右心室流出道漏斗部狭窄37例,漏斗部及肺动脉瓣狭窄14例,主肺动脉及左右肺动脉狭窄113例。合并肺动脉闭锁5例。分别给予自体心包片或自体心包卷成心外管道加宽右心室流出道、同种带瓣血管行右心室-肺动脉连接等处理;合并的心脏畸形作相应的矫正。结果全组手术死亡6例,手术死亡率为3.66%(6/164)。死亡原因严重低心排血量综合征2例,冠状动脉移植后不能脱离体外循环机1例,发生室性心律失常1例,术后发生急性呼吸窘迫综合征2例。术后发生心肺并发症55例,均经治疗后恢复。结论行TOF根治术患者年龄应减小,低心排血量综合征已不是导致术后并发症和死亡的主要原因,术中、术后处理的重点应为预防肺动脉残余梗阻和肺部并发症。     

Lung injury and acute respiratory distress syndrome after cardiopulmonary bypass.

Cardiopulmonary bypass is often followed by pulmonary dysfunction as assessed by measuring the alveolar-arterial oxygenation gradient, intrapulmonary shunt, degree of pulmonary edema, pulmonary compliance, and pulmonary vascular resistance. It is also regarded as a risk factor for development of acute respiratory distress syndrome. On the other hand, cardiopulmonary bypass is associated with a whole body inflammatory response, which involves activation of complement, leukocytes, and endothelial cells with secretion of cytokines, proteases, arachidonic acid metabolites, and oxygen free radicals. Leukocyte adhesion to microvascular endothelium, leukocyte extravasation, and tissue damage are the final steps. Although the inflammatory response to cardiopulmonary bypass often remains at subclinical levels, it can also lead to major organ dysfunction and multiple organ failure. This review article summarizes the recent literature on the molecular and cellular mechanisms involved in the phenomenon of pulmonary dysfunction after cardiopulmonary bypass. It also summarizes reports on the prevalence and mortality of acute respiratory distress syndrome after cardiac surgery.     

Outcomes experience with off-pump coronary artery bypass surgery in women

BACKGROUND: It has been well documented that women have higher morbidity and mortality rates than men following coronary artery bypass graft (CABG) surgery. In view of this evidence, we investigated the following question: compared with on-pump CABG surgery, is there benefit to off-pump CABG surgery in women? METHODS: Our investigation analyzes patient mortality and 13 procedure complications controlling for 35 variables representing patient characteristics and comorbid conditions, and for procedure characteristics for a population of 16,871 consecutive women undergoing off-pump and on-pump CABG surgery at 78 hospitals for the period January 1998 to June 2001. RESULTS: Mean comparisons reveal that the mortality rate for women undergoing off-pump CABG surgery is nearly a percentage point lower than for women undergoing on-pump surgery (3.12 vs 3.90; p = 0.052). The complication rates for all complications analyzed (shock/hemorrhage, neurologic, cardiac, respiratory, renal, acute renal failure, adult respiratory distress syndrome, implant infection, postoperative infection, septicemia, pneumonia, and peripheral vascular) were lower for women off-pump than women on-pump with the exception of mechanical complications. Logistic regression results reveal, after controlling for 35 relevant patient characteristics, comorbid conditions and procedure characteristics, that women undergoing on-pump CABG surgery experience a 42% higher mortality rate (p = 0.0239) than women undergoing off-pump CABG surgery. CONCLUSIONS: Evidence suggests that off-pump CABG surgery may be better for women than on-pump CABG surgery because it appears to reduce mortality and respiratory complications, shorten lengths-of-stay, and increases discharges directly home. None of the 12 other complications investigated demonstrated an advantage for women undergoing on-pump surgery relative to those receiving off-pump surgery.     

Ineffectiveness of methylprednisolone in the treatment of pulmonary dysfunction after cardiopulmonary bypass.

Fifty consecutive adults undergoing elective cardiac surgery with cardiopulmonary bypass received a single dose of methylprednisolone (30 mg/kg) at the time of anesthesia. The results were compared with those in the immediately preceding fifty adult patients who underwent elective cardiac surgery and who did not receive corticosteroids. The age, sex, and weight of the patient, mortality, nature of the lesions treated surgically, bypass time, smoking history, physiologic evidence of preexisting lung disease, preoperative New York Heart Association class, preoperative left ventricular end diastolic pressure, incidence and duration of the postoperative low cardiac output syndrome, postoperative arrhythmias, operative and postoperative blood loss and postoperative hours of respiratory support, dynamic lung-thorax compliance, alveolar arterial oxygen gradient, fraction of wasted ventilation, and incidence of tracheostomy were tabulated and statistically contrasted. The two groups were comparable relative to all preoperative factors, except for a slightly higher end diastolic pressure in the patients who received steroids. Methylprednisolone given at the time of anesthesia was associated with a higher intraoperative blood loss, a higher incidence of low cardiac output syndrome, and an increased requirement for postoperative mechanical ventilation. As bypass time approached three hours, the proportion of patients requiring prolonged support in both groups became similar. It was concluded that pretreatment with methylprednisolone in massive doses had an overall adverse cardiopulmonary effect.     

Risk factors of deep sternal wound infections in coronary artery bypass graft surgery

BACKGROUND: Major infections of sternal wounds after coronary artery bypass graft surgery (CABG) occur infrequently, but when they do, they contribute substantial morbidity and mortality. We identified significant risk factors of deep sternal wound infection (DSWI) following CABG and hoped to plan prophylactic measures for high risk patients in order to reduce the incidence of infection. METHODS: From 1996 to 1997, a total of 620 patients received CABG at a medical center in Taiwan. The surgical wound was examined every day. Wound infections were defined and classified according to Centers for Diseases Control (CDC) definitions. DSWI were defined as those involving the mediastinum, bone or cartilage, and infections beneath the subcutaneous tissue. Several risk factors were analyzed. RESULTS: We identified 17 (2.7%) DSWI. Univariate analysis indicated that ASA scores, surgical risk index, surgeon, postoperative low cardiac output, re-operation for bleeding, re-wiring of sternum, length of postoperative stay in the intensive care unit, postoperative duration of mechanical ventilation, operation time, duration of cardiopulmonary bypass. Independent predictors by multivariate logistic regression analysis were re-operation for bleeding and operation time. A total of 16 organisms were isolated among 14 patients. Staphylococcus accounted for most isolates (93.8%) and the most of them were methicillin-resistant (80%). CONCLUSIONS: Re-operation for bleeding and operation time were the independent predictors.     

Pulmonary artery blood temperature at admission to the intensive care unit is predictive of outcome after on-pump coronary artery bypass surgery

OBJECTIVE: To evaluate whether pulmonary artery blood (PA) temperature on admission to the intensive care unit (ICU) is predictive of postoperative outcome after isolated on-pump coronary artery bypass grafting (CABG). DESIGN: A retrospective study on 1639 patients who underwent isolated on-pump CABG in whom PA temperature at admission to the ICU was available for review. RESULTS: Thirty-three patients (2.0%) died during the in-hospital stay and 87 patients (5.3%) developed low cardiac output syndrome. PA temperature at admission to the ICU was significantly associated with an increased risk of overall postoperative death (p = 0.002), cardiac death (p = 0.03), and low cardiac output syndrome (p < 0.0001), and was significantly correlated with prolonged length of ICU stay (p < 0.0001) and postoperative bleeding (p = 0.001). Patients with high PA temperature had significantly more severe comorbidities, and longer aortic cross-clamping and cardiopulmonary bypass time. The receiver operating characteristic curve showed that PA temperature at admission to the ICU in predicting postoperative death had an area under the curve of 0.660 (p = 0.002) and its best cut-off value was 36.4 degrees C (sensitivity: 63.6%, specificity: 65.2%). When the PA temperature at admission to the ICU was > or = 36.4 degrees C, the postoperative mortality and low cardiac output syndrome rates were 3.6 and 8.3%, whereas they were 1.1 and 3.7% when the PA temperature at admission to the ICU was < 36.4 degrees C (p = 0.001, p < 0.0001), respectively. CONCLUSION: Patients having a PA temperature > or =36.4 degrees C at admission to the ICU after CABG seem to be at higher risk of poor postoperative outcome.     

Renal dysfunction after cardiac surgery with normothermic cardiopulmonary bypass: incidence,risk factors,and effect on clinical outcome

Renal dysfunction is a frequent and severe complication after conventional hypothermic cardiac surgery. Little is known about this complication when cardiopulmonary bypass (CPB) is performed under normothermic conditions (e.g., more than 36 degrees C). Thus, we prospectively studied 649 consecutive patients undergoing coronary artery bypass surgery or valve surgery with normothermic CPB. The association between renal dysfunction (defined as a > or =30% preoperative-to-maximum postoperative increase in serum creatinine level) and perioperative variables was studied by univariate and multivariate analysis. Renal dysfunction occurred in 17% of the patients. Twenty-one (3.2%) patients required dialysis. Independent preoperative predictors of this complication were: advanced age, ASA class >3, active infective endocarditis, radiocontrast agent administration <48 h before surgery, and combined surgery. When all the variables were entered, active infective endocarditis, radiocontrast agent administration, postoperative low cardiac output, and postoperative bleeding were independently associated with renal dysfunction. The in-hospital mortality rate was 27.5% when this complication occurred (versus 1.6%; P < 0.0001). Furthermore, postoperative renal dysfunction was independently associated with in-hospital mortality (odds ratio, 4.1 [95% confidence interval, 1.3-12.8]). We conclude that advanced age, active endocarditis, and recent (within 48 h) radiocontrast agent administration, as well as postoperative hemodynamic dysfunction, are more consistently predictive of postoperative renal dysfunction than CPB factors. IMPLICATIONS: We found that postoperative renal dysfunction was a frequent and severe complication after normothermic cardiac surgery, independently associated with poor outcome. Independent predictors of this complication were advanced age, active endocarditis, and recent (within 48 h) radiocontrast agent administration (the only preoperative modifiable factor), as well as postoperative hemodynamic dysfunction.     

Early neurobehavioral disorders after cardiac surgery: a comparative analysis of coronary artery bypass graft surgery and valve replacement

OBJECTIVE: To analyze neurobehavioral disorders in the early postoperative period after valve replacement and coronary artery bypass graft (CABG) surgery. DESIGN: Prospective study. SETTING: University hospital. PARTICIPANTS: Patients undergoing elective cardiac surgery with cardiopulmonary bypass; 42 patients in the valve replacement surgery group and 42 patients in the CABG surgery group, with both groups matched post hoc for age, sex, and preoperative cognitive status. MEASUREMENTS AND MAIN RESULTS: All subjects were investigated preoperatively as well as 2 and 7 days postoperatively with a comprehensive neuropsychologic and neuropsychiatric assessment. The groups did not significantly differ with respect to the incidence of postoperative neuropsychiatric disorders. Valve replacement surgery patients exhibited more severe neuropsychologic deficits and showed a slower recovery than patients who underwent CABG surgery. In both groups, postoperative neuropsychologic alterations were most marked in fluency, arithmetic, and memory performance. CONCLUSION: These results indicate that patients after valve replacement surgery have a higher risk of postoperative neuropsychologic alterations mainly attributable to temporal lobe dysfunction. This finding corresponds to a specific vulnerability of hippocampal structures to transient hypoxia.     

Myocardial infarct imaging after cardiac surgery.

One hundred and nineteen patients undergoing cardiac surgery had postoperative myocardial imaging performed with technetium pyrophosphate in order to assess the incidence of perioperative myocardial infarction. Fifty-six patients had only coronary artery bypass graft (CABG) surgery, of whom 13(23%) had a positive scintigram. Thirteen patients had CABG with other cardiac surgery and six (46%) had a positive scintigram. Fifty patients had other cardiac surgery but no CABG, and of these eight (16%) had a positive scintigram. The overall incidence of positive scintigrams was 23%, whereas definite or probable ECG diagnosis of infarction was present in 14 patients (12%). Serum levels of cardiac enzymes were higher in patients with positive scintigrams, but this finding did not consistently reach statistical significance. The use of a left ventricular vent during surgery did not correlate with a positive scintigram, nor did the total time on cardiopulmonary bypass or aortic cross-clamping. Patients having cardiac surgery, including CABG and valve replacement, have a 23% overall incidence of positive scintigrams. This suggests that the incidence of infarction after cardiac surgery is higher than can be recognized from the conventional criteria of ECG and enzyme changes.     

心脏瓣膜手术后并发透析依赖的急性肾功能衰竭的危险因素

目的 探讨心脏瓣膜手术后并发透析依赖的急性肾功能衰竭(acute renal failure requiringdialysis,ARF-D)的危险因素.方法 回顾性分析2005年1月至2008年12月心脏瓣膜手术、年龄≥18岁、术前血肌酐＜300 μmol/L的病例资料.术后30天内并发ARF-D者为病例组,共55例.随机抽取同期未并发ARF-D的220例作为对照组.采用单因素分析及多因素Logistic回归探讨并发ARF-D的危险因素.结果 心脏瓣膜术后ARF-D发生率为1.78%,早期病死率65.5%.Logistic回归分析结果显示年龄、二次手术、术前血肌酐、心功能(NYHA)Ⅳ级、术后低心排血量综合征为心脏瓣膜术后并发ARF-D的独立危险因素.病例组与对照组相比,监护室停留时间、术后住院时间差异有统计学意义(P＜0.05).结论 年龄、二次手术、术前血肌酐、心功能Ⅳ级、术后低心排血量综合征为心脏瓣膜术后并发ARF-D的独立危险因素.

Abstract：

Objective To evaluate the risk factors for the postoperative acute renal failure requiring dialysis (ARF-D)after heart valve surgery. Methods Adult patients (age≤18 years) underwent valve surgery with preoperative serum creatinine ＜300 μmol/L were included between January 2005 and December 2008. Fifty patients developed ARF-D within 30 days postoperatively (ARF-D group). While random 220 patients had the same operation without ARF-D served as the control group. Univariate analysis and multivariable logistic regression were used to identify risk factors of ARF-D after valve surgery.Results The incidence of ARF-D was 1.78%, and the early mortality rate was 65.5%. Multivariate analysis identified the following independent risk factors of ARF-D: age, previous cardiac surgery, preoperative serum creatinine, NYHA class Ⅳ,and low cardiac output syndrome. ARF-D group had a longer hospital stay and ICU stay than that of the control group ( P ＜0.001 ). Conclusion Conclusion ARF-D had a higher mortality rate and longer hospital stay following heart valve surgery.Age, previous cardiac surgery, preoperative serum creatinine, NYHA class Ⅳ, and low cardiac output syndrome were the independent risk factors of ARF-D after heart valve surgery.     

MYOCARDIAL INFARCT IMAGING AFTER CARDIAC SURGERY*

One hundred and nineteen patients undergoing cardiac surgery had postoperative myocardial imaging performed with technetium pyrophosphate in order to assess the incidence of perioperative myocardial infarction. Fifty-six patients had only coronary artery bypass graft (CABG) surgery, of whom 13 (23%) had a positive scintigram. Thirteen patients had CABG with other cardiac surgery and six (46%) had a positive scintigram. Fifty patients had other cardiac surgery but no CABG, and of these eight (16%) had a positive scintigram. The overall incidence of positive scintigrams was 23%, whereas definite or probable ECG diagnosis of infarction was present in 14 patients (12%). Serum levels of cardiac enzymes were higher in patients with positive scintigrams, but this finding did not consistently reach statistical significance. The use of a left ventricular vent during surgery did not correlate with a positive scintigram, nor did the total time on cardiopulmonary bypass or aortic cross-clamping. Patients having cardiac surgery, including CABG and valve replacement, have a 23% overall incidence of positive scintigrams. This suggests that the incidence of infarction after cardiac surgery is higher than can be recognized from the conventional criteria of ECG and enzyme changes.     

Five-year experience in aortic root replacement with the flanged composite graft

BACKGROUND: Replacement of the aortic root with a composite graft containing a prosthetic mechanic valve is the preferred surgical procedure for tailoring the aortic root. The aim of this study is to determine the 5-year experience with the composite root replacement using our new modification of the Bentall technique. METHODS: Between January 1996 and June 2001, 96 patients underwent aortic root replacement using a flanged composite graft. Eighty patients (83.3%) were male, and 16 patients (16.7%) were female with a mean age of 48.7 +/- 14.4 years. Indications for operation were a true or false aneurysm (65.6%), severe calcified aortic valve stenosis (4.2%) or severe aortic insufficiency (2.1%) with dilated ascending aorta, acute dissection (2.1%), or combination of indications (26%). Thirty-one patients (32.3%) received a concomitant cardiac procedure. Mean aortic cross-clamp time was 89.5 +/- 28.6 minutes, and mean cardiopulmonary bypass time was 146.2 +/- 45.6 minutes. Total follow-up was 253.9 patient-years. RESULTS: Operative mortality was 8.3% (8 patients). The causes of hospital mortality were severe bleeding (3 patients), low cardiac output syndrome (2), acute respiratory distress syndrome (2) and cerebrovascular event (1). No patient died of flange-related complications. Univariate predictors of early mortality were low cardiac output syndrome (p < 0.001), neurologic complication (p = 0.03), and renal complication (p = 0.03). Multivariate analysis demonstrated only low cardiac output syndrome to be significant (p = 0.001) predictor for early mortality. There were five (5.7%) late deaths. Actuarial survival was 82.65% +/- 4.8% at 5 years (1.95% patient-year). Cox proportional hazards regression analysis demonstrated only low cardiac output syndrome to be significant (p = 0.032) predictor for late mortality. Actuarial freedom from prosthetic- and technique-related mortality was 100% at 5 years. CONCLUSIONS: The flanged composite graft offers excellent long-term results, with very low prevalence of prosthetic-related complications. The new created sinuses and the flange are especially helpful to continue physiologic function of the aortic root.     

Evaluation for factors associated to early tracheal extubation after coronary artery bypass grafting]

Recent studies suggest that early tracheal extubation after coronary artery bypass grafting (CABG) may reduce intensive care unit use and cost. During recent two years, 96 patients were underwent CABG under cardiopulmonary bypass by low-dose fentanyl and isoflurane anesthesia. We compared two groups of patients for evaluation of factors associated to early tracheal extubation. 47 cases (Group A) were extubated within six hours (average 4.4 hrs) following operation, and 26 cases (Group B) were extubated later than twelve hours (average 57.5 hrs). It is suggested that emergency cases, female, elderly patients, dysfunction of kidney and long operation time associated to late extubation. But early extubation after CABG does not increase perioperative morbidity except for the cases that fell in low cardiac output syndrome or postoperative respiratory complications.     

Predictors and outcome of gastrointestinal complications in patients undergoing cardiac surgery

OBJECTIVE: To determine the incidence and independent predictors of gastrointestinal complications (GICs) following cardiac surgery. SUMMARY BACKGROUND DATA: Gastrointestinal ischemia and hemorrhage represent a rare but devastating complication following heart surgery. The profile of patients referred for cardiac surgery has changed during the last decade, questioning the validity of previously reported incidence and risk factors. METHODS: We retrospectively analyzed prospectively collected data from 4819 patients undergoing cardiac surgery between 1998 and 2004. Patients with GICs were compared with the entire patient population. Study endpoints were mortality, postoperative morbidities, and long-term survival. RESULTS: GICs occurred in 51 (1.1%) patients. Etiologies were intestinal ischemia (n = 30; 59%) and hemorrhage (n = 21; 41%). The incidence decreased during the study period (1998-2001: 1.3%, 2002-2004: 0.7%; P = 0.04). The incidence per type of procedure was as follows: coronary artery bypass grafting (CABG)/valve (2.4%), aortic surgery (1.7%), valve surgery (1.0%), and CABG (0.5%; P = 0.001). Multivariate analysis revealed age (odds ratio [OR] = 2.1), myocardial infarction (OR = 2.5), CHF (OR = 2.4), hemodynamic instability (OR = 2.8), cardiopulmonary bypass time >120 minutes (OR = 6.2), peripheral vascular disease (OR = 2.2), renal (OR = 3.2), and hepatic failure (OR = 10.8) as independent predictors of GICs. The overall hospital mortality among patients with GICs was 33%. Long-term survival was significantly decreased in patients with GICs compared with the control group. CONCLUSIONS: Gastrointestinal complications following cardiac surgery remain rare with an incidence <1% in a contemporary series. The key to a lower incidence of GICs lies in systematic application of preventive measures and new advances in intraoperative management. Identification of independent risk factors would facilitate the determination of patients who would benefit from additional perioperative monitoring. Future resources should therefore be redirected to mitigate GICs in high-risk patients.     

Effects of cardiopulmonary bypass on glucose homeostasis after coronary artery bypass surgery.

OBJECTIVE: Hyperglycaemia is associated with increased mortality and morbidity after cardiac surgery. While surgical stress results in hyperglycaemia after all operations, it has been suggested that cardiopulmonary bypass is the dominating contributor after cardiac surgery. This study aimed to determine the contribution of cardiopulmonary bypass to hyperglycaemia after coronary artery bypass. METHODS: Patients scheduled for primary coronary artery bypass grafting were randomised to surgery with or without cardiopulmonary bypass. All patients received continuous insulin infusions during the initial 24-h period. Glucose was infused (100mg/kg per h) postoperatively in the intensive care unit but not during surgery. Blood glucose was measured 4 times daily until the third postoperative day. Serum insulin, insulin-like growth factor-1 and its binding protein were determined. RESULTS: Average blood glucose during the day of surgery did not differ between groups, but 30% more insulin (P=0.003) was required when cardiopulmonary bypass was used. Blood glucose 2-3h after meals was higher in patients using cardiopulmonary bypass during the first 3 postoperative days. Fasting blood glucose was still equally elevated 20-30% in both groups on the third postoperative day. Insulin-like growth factor-1 decreased more (P=0.01) and insulin-like growth factor binding protein-1 increased more (P<0.001) with cardiopulmonary bypass than without. The ratio of insulin-like growth factor-1 concentration to the concentration of its binding protein-1 was more negative (indicating greater catabolism) with cardiopulmonary bypass than without both postoperatively (P=0.002) and on the third postoperative day (P=0.02). Insulin-like growth factor-1 standard deviation score, also a measure of catabolism, was greater after surgery with cardiopulmonary bypass than without (P=0.02). CONCLUSIONS: Glucose homeostasis is disturbed preoperatively for many non-diabetic patients undergoing coronary bypass surgery. Cardiopulmonary bypass exacerbates the catabolism and disturbed glucose homeostasis that is induced also to a lesser degree by surgery without cardiopulmonary bypass.     

Postoperative intensive care in infants and children after cardiac surgery

Background The postoperative course of infants and children after open heart surgery is often complicated by cardiopulmonary insufficiency or low cardiac output. Methods From January 1989 to April 1992 441 infants and children with congenital heart disease underwent cardiac surgery. 128 of these patients (29%) required prolonged or extensive intensive care because of cardiopulmonary insufficiency or low cardiac output. Aortic cross clamp and cardiopulmonary bypass times were measured in all patients. In the postoperative period duration of mechanical ventilation, duration of intensive care, special monitoring and therapeutic strategies and clinical scores were documented. Results The overall mortality rate was 9.9%, the mortality rate in patients with postoperative cardiopulmonary insufficiency or low cardiac output was 34%. The mortality rate increased significantly up to 73% when the cardiopulmonary bypass time exceeded 200 min. Mean duration of intensive care of survivors (S) and nonsurvivors (NS) was 10.3±0.8 and 4.1±1.2 days, respectively (p<0.01), mean duration of mechanical ventilation was 7.1±0.5 (S) and 4.1±1.2 (NS) days, respectively (p<0.01). NS had a significantly higher degree of physiologic derangement assessed by the Acute Physiologic Score for Children and needed more monitoring and therapeutic interventions assessed by the Therapeutic Intervention Scoring System than S. Conclusion Complex cardiac surgery, a cardiopulmonary bypass time over 200 min, high catecholamine infusion rates combined with a persisting low mean arterial pressure are associated with a high postoperative mortality rate in infants and children with congenital heart defects.     

Neurological injury after surgery for ischemic heart disease: risk factors, outcome and role of metabolic interventions.

OBJECTIVES: Neurological complication remains a feared and increasing problem in association with cardiac surgery. The aim of this study was to analyze risk factors for neurological complications in a cohort of patients in whom inotropes for weaning from cardiopulmonary bypass was gradually replaced by metabolic treatment. METHODS: The records of 775 consecutive patients undergoing coronary artery bypass grafting (CABG) or combined CABG+valve procedures were examined. Forward stepwise multiple logistic regression analysis was used for statistical evaluation of independent risk factors. RESULTS: The incidence of neurological injury was 1.8% in patients undergoing isolated CABG and 5.4% after combined CABG+valve procedures. After cross-validation multivariate analysis identified history of cerebrovascular disease, advanced age and aortic cross-clamp time as independent risk factors for postoperative cerebral complications. Chronic obstructive pulmonary disease and number of bypasses also emerged as risk factors in the primary analysis. CONCLUSIONS: In general, markers for advanced atherosclerosis, with history of cerebrovascular disease as the most important, emerged as predictors for neurological injury. Although it did not enter the final risk model, the results also suggest that postoperative heart failure deserves further surveillance as a potential risk factor for neurological complications. However, no evidence for untoward neurological effects associated with glutamate or glucose-insulin-potassium treatment was found.     

Stroke after cardiac surgery: a risk factor analysis of 16,184 consecutive adult patients

BACKGROUND: Stroke remains a devastating complication after cardiac surgical procedures despite advances in perioperative monitoring and management. The purpose of this study was to determine the predictors of stroke in a large, contemporary cardiac surgery population. METHODS: Prospective data on 16,184 consecutive patients undergoing cardiac surgery (coronary artery bypass grafting [CABG], n = 8,917; beating heart CABG, n = 1,842; aortic valve surgery, n = 1,830; mitral valve surgery, n = 708; double or triple valve surgery, n = 381; CABG and valve surgery, n = 2,506) between April 1996 and August 2001 were subjected to univariate and multivariate analysis. Stroke was defined as any new permanent (manifest stroke) or temporary neurologic deficit or deterioration (transient ischemic attack or prolonged reversible ischemic neurologic deficit) and was confirmed by computed tomography or magnetic resonance imaging whenever possible. RESULTS: Overall incidence of stroke was 4.6% and varied between surgical procedures (CABG 3.8%; beating-heart CABG 1.9%; aortic valve surgery 4.8%; mitral valve surgery 8.8%; double or triple valve surgery 9.7%; CABG and valve surgery 7.4%). Of 63 patient-specific and treatment variables, 54 were found to have a significant univariate association with postoperative stroke. Multivariable analysis revealed 10 variables that were independent predictors of stroke: history of cerebrovascular disease, peripheral vascular disease, diabetes, hypertension, previous cardiac surgery, preoperative infection, urgent operation, CPB time more than 2 hours, need for intraoperative hemofiltration, and high transfusion requirement. Beating heart CABG was associated with a lower incidence of stroke in this multivariable analysis. CONCLUSIONS: Identification of predictors for stroke is important for understanding the pathogenesis of this devastating complication as well as for developing preventative strategies. Although retrospective analyses can be subject to selection bias we believe beating heart CABG is associated with a lower incidence of stroke and may therefore improve patient outcomes.     

Limitations of additive EuroSCORE for measuring risk stratified mortality in combined coronary and valve surgery.

OBJECTIVE: To study the use of the additive and logistic European System for Cardiac Operative Risk Evaluation (EuroSCORE) to predict mortality following adult combined coronary artery bypass grafting (CABG) and valve surgery. METHODS: Data were collected prospectively, from all four centres providing adult cardiac surgery in the north west of England, on 1769 consecutive patients undergoing combined CABG and valve surgery between April 1997 and March 2002. Observed in-hospital mortality was compared to predicted mortality as determined by both additive and logistic EuroSCORE. RESULTS: Observed mortality for simultaneous CABG and valve surgery was 8.7%, compared to 6.7% (additive) and 9.4% (logistic). Sixty-five percent of patients were classified as high-risk (additive EuroSCORE >5); the observed mortality was 11.5%, compared to 8.1% (additive) and 12.8% (logistic). Discrimination was similar in both systems as measured by the C statistic (additive 0.73, logistic 0.73). CONCLUSIONS: The logistic EuroSCORE is more accurate at predicting mortality in simultaneous CABG and valve surgery, as the additive EuroSCORE significantly under-predicts in this high-risk group.