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The number of subjects undergoing major noncardiac surgery who are at risk for perioperative myocardial infarction (MI) is growing worldwide. It has been estimated that 500,000 to 900,000 patients suffer major perioperative cardiovascular complications every year, with consequent heavy, long-term prognostic implications and costs. It is well known that perioperative MIs don’t share the same pathophysiology as nonsurgical MIs but the relative role of the different, potential triggers has not been completely clarified. Many aspects of the perioperative management, including risk-stratification and prophylactic or postoperative interventions have also not been completely defined. Throughout recent years many resources have been invested to clarify these aspects and experts have developed indices and algorithm-based strategies to better assess the cardiac risk and to guide the perioperative management. The scope of the present review is to discuss the main aspects of perioperative MI in noncardiac surgery, with particular regard to epidemiology, pathophysiology, preoperative risk stratification, prophylaxis and therapy.

Background: The circadian variation that affects atherosclerosis has not been studied in the surgical patient. The circadian variation in mortality dependent on the time of surgery was examined in patients undergoing coronary artery bypass graft (CABG) surgery. Methods: A 4-year retrospective review of all CABG patients (n = 3140) from 1999 to 2002 was undertaken. The patients were divided into elective, urgent, and emergency cases. The cases were subdivided according to the start time of the operation as morning (7 AM to 2 PM = AM), afternoon (2 PM to 8 PM = AF), and night (8 PM to 7 AM = NT). The outcome was mortality within 30 days and compared for three different time frames: (1) AM versus AF (2) AM versus NT (3) AF versus NT for each prioritized group. Risk factors and number of anastamoses were compared for each group. Sigma Statistical package and Z-test for two group comparison were used for analysis. t-Test was used to compare age and ejection fraction. Results: No statistically significant difference in mortality was observed for the elective and urgent groups for each of the time periods compared. The emergency cases had significantly increased deaths in the AM and NT compared to the AF (p < 0.01 and p < 0.05, respectively). There was no statistically significant difference with respect to age, gender, number of anastamoses performed, ejection fraction, and preoperative risk factors between groups. Conclusions: The mortality for nonemergent CABG is independent of the timing of surgery. Circadian variation does not influence the outcome in cardiac surgical patients.

day after CABG. Results: postoperative AF was observed in 37 (37%) of 101 patients. Patients with AF were older (68.4 -4- 6.9 vs. 63.8 -4- 9.4 years, p < 0.01) and had a significantly lower CHRS (3.32 4- 1.83 vs. 4.17 4- 2.19 ms/ram Hg, p < 0.05). The predictive power for a pathological CHRS achieved a specificity of 63%, a sensitivity of 60%, a negative predictive value of 73%, a positive predictive value of 48% and an accuracy of 61%. Patients with postoperative AF stayed longer in the intensive care unit (2.9 4- 1.7 vs. 1.3 4- 0.5 days, p < 0.0001) and in hospital (13.5 4- 4.3 vs. 11.4 4- 1.1 days, p < 0.0004). Conclusion: the results of our study show that the risk for AF after CABG could preoperatively be predicted with an analysis of CHRS. The predictive power of a pathologic CHRS could be used for a preoperative risk stratification.

The National Veterans Affairs (VA) Surgical Risk Study was initiated in 1991 with the goal of developing and validating risk-adjusted models for the prediction of surgical outcomes that would allow a comparative assessment of the quality of surgical care among multiple facilities. 87,000 non-cardiac surgeries performed under anesthesia at 44 VA Medical Centers identified preoperative serum albumin as the strongest predictor of surgical success. This study evolved into the National Surgical Quality Improvement Program (NSQIP) which now collects prospectively preoperative risk factors, intraoperative information and postoperative outcomes on all patients in the VA undergoing major surgery. The NSQIP data was utilized in one institution to explore the relationship of preoperative albumin on morbidity and mortality on 1011 cardiac surgery patients from 10/1/95-9/30/98. The results were as follows: Albumin30-day Morbidity (1 or more post operative complication)30-day Mortality2.1(n=4)75%0%2.1-2.7(n=30)40%13%2.8-3.4 (n=219)29%5%3.5-4.0(n=516)22%2%>4.0 (n=242)14%2% Statistical analysis showed significant relationship between preoperative albumin and morbidity and mortality with p-values (.006) and (.002) using chi-square tests. A mechanism for identifying patients with hypoalbuminemia is being actively explored between the Pre-Admission Testing Clinic, Laboratory and Nutrition Services, so early nutritional intervention can be implemented. Further studies evaluating the impact of early nutritional intervention on morbidity and mortality is warranted.

Lung resections are correlated to high mortality (4–6%) and morbidity (20–40%) that can increase in high risk patients. Objectives of this study is to analyze preoperative risk factors, in a group of high risk patients undergoing thoracotomy for lung cancer and to assess the relationship with postoperative complications.

Objective: To determine differences in perioperative care and outcomes for patients with colon cancer enrolled in Medicare health maintenance organizations compared with similar fee-for-service nonenrollees. Methods: Cross-sectional evaluation of hospital care and posthospital outcomes with data obtained from medical records. Nineteen health maintenance organizations representing all model types were selected from 12 states. The nonenrollee sample was drawn from the same areas. The sample included 412 enrollees and 401 nonenrollees, representing 65 hospitals for health maintenance organizations and 61 hospitals for fee-for-service. Results: Nonenrollees were slightly older and had higher preoperative risk. Enrollees had shorter intervals between admission and surgery (enrollees, 1.55 days vs nonenrollees, 2.85 days). Differences in length of stay (enrollees, 10.9 days vs nonenrollees, 14.2 days) persisted even after controlling for preoperative health status. Differences in admissions to intensive care units (enrollees, 36.4% vs nonenrollees, 44.4%) were highly influenced by preoperative health status. Nonenrollees were more significantly likely to receive preoperative antibiotics, postoperative testing (eg, postoperative chest radiographs and electrocardiograms), and postoperative patient-controlled analgesia. Tumor staging was similar for both groups. Enrollees were more likely to be discharged home, while nonenrollees were more likely to be discharged to a nursing home. There were no significant differences in hospital deaths or postdischarge readmissions. Conclusions: Health maintenance organization enrollees with colon cancer received less clinical services of several types than similar patients in fee-for-service settings, had shorter hospital stays, and were less likely to be discharged to nursing homes. However, there was no evidence that they experienced different outcomes. Arch Intern Med. 1997;157:1878-1884

We sought to identify the types of, prevalence of, and predisposing factors for the development of surface keratopathy after penetrating keratoplasty. We reviewed the records of 120 corneal grafts performed over a 15-month period. Twenty patients were excluded from the study. Fifty-three men and 47 women composed the group studied. All transplants were performed by the same surgeon. Retrospective data from patients' records were gathered preoperatively and from postoperative visits at 1 week and at 1, 2, 3, and 4 months. Data included preoperative medical and demographic data, operative time, postoperative medication regimens, assessment of the presence and degree, if present, of punctate epithelial keratopathy (PEK), hurricane keratopathy, macroepithelial defects, microcystic edema, bullous edema, and filamentary keratitis. In addition, information on the donor material was recorded. Surface disease and normal groups were compared to identify risk factors for the occurrence of surface abnormalities. Thirty-three of the patients demonstrated persistent surface abnormalities. Coarse PEK was the most common surface abnormality in the sample studied and was most prominent in the first week after surgery. Postoperative surface keratopathy was not statistically associated with preoperative diagnosis, donor age, death-to-preservation time, preservation-to-surgery time, or donor epithelial status. However, corneal recipients in the group with surface keratopathy were significantly older (mean, 68.7 years) than patients in the group with no surface abnormalities (mean, 52.6 years; Mann-Whitney U test, p < 0.001). Although many factors may contribute to the normal integrity of the corneal surface after keratoplasty, recipient age is of key importance in the development of surface disease.

To the Editor. —Dr Silber and colleagues 1 strongly recommend that complication rates in coronary artery bypass graft (CABG) surgery should not be used to judge hospital quality of care. We have serious concerns about the validity of this conclusion because of several limitations in their study. First, we question both the definitions and rates of complications noted in the study. Their conceptualization of postoperative complications for CABG surgery appears flawed. It is important to distinguish between complications that are common sequelae of patients' illness (eg, congestive heart failure) and those that are more likely to result from substandard care (eg, deep wound infection). Despite the authors' definition of a complication as "a finding not noted on admission, but present after the second hospital day or during or after surgery," clinical conditions present before CABG surgery (eg, hypotension, congestive heart failure, and cardiac emergency) that are preoperative risk factors could

To the Editor. —I fail to understand the wisdom of excluding input from an anesthesiologist in the design or implementation of the recently published study by Marcantonio et al. 1 The authors' attempt to link postoperative delirium to preoperative risk factors without controlling for time of surgery start, anesthetic technique, postoperative analgesic technique, need for continued postoperative ventilation and sedation, and need for postoperative intensive care flies in the face of modern science. For example, many anesthesiologists currently use high-dose opiate techniques for major abdominal vascular repair (ie, aortic aneurysm surgery), and many of these patients spend their first 24 postoperative hours in an intensive care unit. That these patients are at higher risk for postoperative delirium or confusion than a healthy 40-year-old woman undergoing tubal ligation comes as no surprise to any anesthesiologist. The authors' comment that intervention strategies for reducing the probability of postoperative delirium "include close monitoring and

We performed a systematic review of 28 studies that examined preoperative risk factors for postoperative renal failure. Included in the studies were 10,865 patients who underwent either vascular, cardiac, general, or biliary surgery. No two studies used the same criteria for acute renal failure. Variability in definitions of renal failure, lack of consistent criteria for establishing risk factors, and nonuniformity in the statistical methods employed result in a literature that is not adequate to support a comprehensive quantitative review. Of the 30 variables considered in the studies, preoperative renal risk factors, such as increased serum creatinine, increased blood urea nitrogen, and preoperative renal dysfunction were repeatedly found to predict postoperative renal dysfunction. The literature provides little quantitative information concerning the degree of risk associated with other factors. Cardiac risk factors, such as left ventricular dysfunction, were reported to be predictive of postoperative renal failure more consistently than was advanced age.

Although risk factors for mortality after cardiac surgery have been identified, there is no widely applicable method for readily determining risk of postoperative morbidity based on preoperative severity of illness. The goal of this study was to develop a model for stratifying the risk of serious morbidity after adult cardiac surgery using readily available and objective clinical data. After univariate analysis of risk factors in 3,156 operations, 11 variables were identified as important predictors by logistic regression (LR) analysis and used to construct an additive model to calculate the probability of serious morbidity. Reliable correlation was found between a simplified additive model for clinical use and the LR model. The clinical and logistic models were then tested prospectively in 394 patients and demonstrated a pattern of increasing morbidity with ascending scores similar to that predicted by the reference group. Increasing clinical risk score was also associated with a greater frequency of individual complications as well as prolongation of ICU stay. This study demonstrates that it is feasible to design a simple method to stratify the risk of serious morbidity after adult cardiac surgery. With further prospective multicenter refinement and testing, such a model is likely to be useful for adjusting severity of illness when reporting outcome statistics as well as planning resource utilization. (Chest 1992; 102:36–44)

Study Objective: To evaluate the effect of a preprinted, risk-specific consent form on the amount of anesthetic risk information patients retain from the preoperative interview. Design: Postoperative survey of consecutive inpatients to determine risk information retained before and after implementation of a preprinted anesthesia consent form, using standard preoperative risk discussions. Setting: Inpatient units of a university medical center. Patients: Two groups of patients, both of whom received a standard oral discussion of anesthetic risk information, were compared. Patients in the control group (125 consecutive inpatients) received this information only orally and were interviewed two weeks prior to implementation of a preprinted anesthesia consent form. Patients in the study group (92 consecutive inpatients) received this information orally and via a preprinted consent form and were interviewed between the fourth and sixth weeks after implementation of a preprinted anesthesia consent form. Interventions: Anesthesia residents discussed five standard anesthetic risks with elective, adult inpatients (n = 233) during a two-week period immediately before and between the fourth and sixth weeks after instituting the mandatory use of a risk-specific anesthesia consent form. These patients were interviewed postoperatively by one of the authors to determine the amount of anesthesia risk information they retained. Measurements and Main Results: Results of the postoperative survey showed that patients in the control group retained more information concerning anesthetic risks than did those in the study group (33% vs 19%, p Conclusions: to improve the informed consent process, either a better method of presenting the preprinted, risk-specific consent form or another method of simultaneously conveying and documenting risk information is needed.

To the Editor. — A ranking of New York hospitals by cardiac surgery mortality rates, adjusted for preoperative risk, appeared in the New York Times (December 5, 1990:B10) in response to the study of "Adult Open Heart Surgery in New York State"1 published in JAMA . Ranking was based on rate of deaths related to heart surgery and adjusted for preoperative condition. Results from the first 6 months of 1990 were compared with the same period in 1989. Several substantive arguments were offered by staff at involved institutions, such as alterations in patient care and case mix, to explain both favorable and unfavorable trends. I believe that a more accurate argument is based on a common and often unrecognized phenomenon: regression to the mean. This is the tendency of outlying values to be more toward the average on repeat measurement. If this principle were operating in this data set, hospitals with

A multivariate analysis of 30 preoperative risk factors was undertaken in 248 patients who underwent surgery alone for common bile duct (CBD) stones and in 190 patients who had endoscopic sphincterotomy (ES), 77 of whom subsequently also had surgery. Independently significant risk factors in those undergoing surgery were the serum bilirubin level, the use of preoperative ES, and the presence of medical risk factors; in patients undergoing ES, only the serum bilirubin and albumin, but not medical risk factors, were of independent significance. The major implications of this study are, first, that high-risk patients should be treated by ES without subsequent surgery, and second, that "fit patients should be treated by surgery alone without routine preoperative ES.

70歳以上の高齢者胸部食道癌89例について術前リスク評価と術後合併症, 手術成績との関連より手術適応上の問題点について検討した. 術前リスク評価では70歳以上の症例に重要臓器機能の障害を持っているD群の占める割合が高かった. 肺合併症の発生率は70歳以上では69歳以下と比べ有意に高い値をしめし, 特にD群で高率に発生をみた. 術後合併症の発生と在院死亡率との間には相関を認めず70歳以上の群と69歳以下の群でも在院死亡率には有意差を認めなかった. 5年生存率は69歳以下の群と70歳以上の群との間に有意差を認めず, 高齢者といえども慎重な術前後の管理を前提とするならぼ十分手術適応はあると考えられる.

The results of operative treatment of postinfarction left ventricular aneurysms in 169 patients undergoing operation since 1970 are analyzed in this report. Maximum follow-up extended to 7 years (average 2.9 years). Average patient age was 56 years (range 34 to 82 years). Nearly all patients (94 percent) had left anterior descending coronary artery disease with anterior aneurysm formation and 73 percent had multivessel disease. Sixty-eight percent of patients underwent aorta-coronary bypass grafting (ACBG) and/or mitral valve replacement (MVR) concomitantly with aneurysmectomy. The over-all operative mortality rate was 17.8 percent. Preoperative factors that correlated significantly (p

Bei 245 Patienten mit Speiserohrencarcinomen, die seit dem 1. l. 1964 in der Chirurgischen Universitatsklinik Koln operiert wurden, konnte eine signifikante Beziehung zwischen tumorspezifischen Risikofaktoren und der Fruhprognose nicht festgestellt werden. Mit Hilfe mathematischer Modelle war es moglich, organspezifische Risikoindices zu entwickeln, die Patientengruppen mit signifikant erhohtem Operationsrisiko erfassen konnten. Ihre Aussage fur den einzelnen Patienten war jedoch zu ungenau, um aus ihnen eine Entscheidung fur das operative Vorgehen ableiten zu konnen.

This retrospective study of 120 patients identified three separate variables that influence operative mortality in patients with abdominal aortic aneurysms. These are age, presence or absence of symptoms, and presence of three preoperative risk factors or more. Based on this study and the fact that any aneurysm may rupture without warning, we conclude that observation of good risk asymptomatic patients until symptoms occur is unjustified. Asymptomatic patients less than seventy years old can undergo abdominal aortic aneurysmectomy with minimal mortality. Carefully selected asymptomatic patients more than seventy years old can also under surgical intervention with acceptable results.

In order to assess the influence of preoperative risk factors on the late postoperative course, 186 consecutive patients in whom coronary artery bypass graft (CABG) was performed for chronic stable angina (169 men, 17 women, mean age ±SD 54±8 years) were followed for an average of 54 (6 to 113) months. The overall five-year survival rate by life-table analysis was 90 ±2 percent. The postoperative course was considered favorable in 112 patients (60 percent) in whom angina was absent or improved by at least 2 NYHA classes throughout the entire follow-up, and was unsatisfactory in 74 patients. It was concluded that the late postoperative course of patients with CABG was unfavorably influenced by the presence of two or three risk factors, and a high preoperative cholesterol level was the only single risk factor associated with unsatisfactory outcome.

During the six year period ending in December 1986, 103 patients with ruptured abdominal aneurysms presented to the unit. Ninety-two patients underwent surgery with a mortality of 39%. There was an increase in mortality with preoperative risk factors, extent of surgery, prolonged stay in ICU, complications and amount of blood transfused. However, only the latter was statistically significant. Age, the distance traveled by the patient before arrival at the hospital, systolic blood pressure on presentation and duration of operation did not affect the mortality.

Patients who undergo thoracic surgical procedures often are at high risk. Several risk-scoring systems have been advocated; they are complex and unwieldy. Also, physicians-in-training need a teaching tool with a consistent format. A program for these needs has been written in the high-level language Modula-2 for the Macintosh Computer. The user enters height, weight and easily obtainable data. Normal values are accessed via a 'window' which is triggered by clicking the 'mouse'. When pulmonary data is entered, cardiovascular system questions are presented. The user is finally presented with entered data, calculated data and a risk estimate. Complications estimates are derived from a special LEARNER file. The program 'learns' from a constantly expanding database.

In 36 patients who underwent surgery for carcinoma of the oesophagus (21 patients subjected to blunt mediastinal dissection, 15 to thoracotomy) the preoperative status was determined by means of cardiopulmonary stepwise diagnosis and an individually adapted concomitant therapy was performed. A scheme for preoperative risk assessment which is equally important for both methods was evolved from the postoperative changes of VC, FEV1 and the preoperative values for RV/TLC, FEV1/VC, paO2 and paCO2 after retrospective analysis of the individual complication rates (60% cardiopulmonary). The 30-day lethality was 11%.

SummaryOperated acute DeBakey type I aortic dissection has to be considered as a chronic aortic disease with the potential of late distal dilatation with aneurysm formation and need for reoperation. Several intraoperative strategies have been devised to prevent late complications. However, the increased operative risk associated with a more aggressive initial approach in an emergent setting has to be balanced against the relatively low incidence of late reoperations. Further studies will have to identify preoperative risk factors for late distal aortic complications more precisely in order to select patients who might benefit the most from these newer surgical strategies.

Objective Increasingly, patients with previous sternotomy require aortic valve replacement. We compared outcomes of reoperative aortic valve replacement after previous sternotomy and primary aortic valve replacement by surgical era. Effect of initial cardiac operation on reoperative aortic valve replacement was also investigated. Methods Between January 1996 and December 2007, a total of 1603 patients undergoing elective aortic valve replacement were entered prospectively into our clinical database. Patients were divided into eras A (1996–1999), B (2000–2003), and C (2004–2007). A total of 191 patients (12%) had previous sternotomy for coronary artery bypass grafting (n = 88), coronary artery bypass grafting with aortic valve replacement (n = 16), aortic valve replacement with or without other aortic procedure (n = 70), and other cardiac procedures (n = 17). Mean ages were 66.5 ± 13.1 years in reoperative group and 65.5 ± 14.9 years in primary group. Results Mortality in reoperative group decreased significantly with time (A 15.4% vs B 15.1% vs C 2.0%, P = .004) and was equivalent to primary group in era C (3.5% vs 2.0%, P = .65). Major complications also significantly decreased with time in reoperative group (A 25.6% vs B 17.0% vs C 6.1%, P = .006). Importantly, patients had more comorbidities with time and increased preoperative risk in era C. There were no differences in outcome by initial cardiac operation in reoperative group. Conclusions Reoperative aortic valve replacement now carries similar morbidity and mortality to primary replacement. Risk of reoperation is not affected by primary operation.

IntroductionUnlike with abdominal aortic aneurysms (AAA), women appear to have an almost comparable incidence as men for thoracic aortic aneurysms (TAA). However, the extent to which a patient's sex influences endograft treatment of TAA has not been reported. The current study analyzes the influence of sex on the endovascular management of TAAs.MethodsA total of 421 patients (265 men and 156 women) were identified as part of the TAG (W. L. Gore and Associates, Flagstaff, Ariz) thoracic stent graft trials. Preoperative risk factors, intraoperative events, and 365-day follow-up data were analyzed.ResultsAmong 18 different preoperative risk factors evaluated, women were less likely to have prior vascular procedures (38.9% vs 55.3%; P = .004). A trend was noted toward lower rates of coronary artery disease (41.3% vs 51.2%; P = .09) and smoking (77.8% vs 85.6%; P = .08). Women were also more likely to be nonwhite (81.4% vs 87.9%; P = .007). Women had a smaller mean external iliac vessel diameter (7.1 vs 9.0 mm; P < .001), resulting in 24.4% vs 6.0% conduit use (P < .001) for device delivery. Local access site complications were significantly higher in women (14.1% vs 4.5%; P < .001). No difference was noted between sexes in the technical success rate (device delivery and successful aneurysm exclusion) or the major adverse event rate at 30 days (26.3% vs 20.4%; P = .18). The overall length of stay was 5.5 ± 6.2 days for female patients vs 4.8 ± 13.0 days (P < .001). No sex-related difference was noted in endoleak rate, aneurysm rupture, prosthetic migration, or aneurysm diameter change at 365 days.ConclusionsNo significant differences in major outcomes were noted between men and women treated with endovascular repair of TAA at 1 month and 1 year. Women have more vascular complications, which are associated with smaller access vessels. A lower threshold for using conduits in women may be a more prudent approach.

Objectives this study reviews and compares carotid endarterectomy (CEA) performed under local anaesthesia (LA) with CEA performed under general anaesthesia (GA) in a single institution. Methods data were collected prospectively from 240 CEA procedures. 140 GA CEA procedures are compared to 100 LA CEA procedures in terms of outcome, operative techniques, complications, and length of stay. Results the groups were similar for age, gender distribution and preoperative risk factors. There were more asymptomatic patients in the LA group. There were no significant differences in death, stroke or death/stroke rate between the two techniques. LA CEA was associated with lower shunt rate (LA 13%, GA 50%, p

Summary The present study was undertaken to assess surgical risk in 112 severely hypertensive patients with renovascular disease secondary to atherosclerosis. The influence of preoperative risk factors and the surgical procedure on surgical mortality was also investigated. Extrarenal atherosclerosis was present in 51 percent of the patients, and hypertensive target organ damage was present in 66 percent. Renal artery reconstruction was performed unilaterally in 92 patients and bilaterally in 20 patients. Simultaneous aortoiliac operations were performed in 25 patients. There were nine operative deaths (8 percent). The presence of extrarenal atherosclerosis was particularly associated with mortality (14 percent compared with 1.8 percent when it was absent;p=0.02). The surgical procedure also represented a significant risk; the mortality rate was 1.4 percent if surgery was restricted to unilateral reconstruction, but otherwise it increased to 20 percent (p=0.001). This increase in mortality rate was clearly associated with aortoiliac surgery (20 percent compared with 4.6 percent when aortoiliac surgery was not performed;p=0.025) and could be explained by the increased blood loss during operation. We conclude that the surgical treatment of renovascular disease secondary to atherosclerosis can be safely performed, provided that extrarenal atherosclerosis is absent and that simultaneous aortoiliac surgery can be avoided.