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Background: The predictors and causes of stroke after valvular surgery are incompletely defined. We examined the incidence, predictors, and mechanisms of stroke during valvular procedures over a 15-year time period., Methods and Results: We retrospectively reviewed prospectively gathered data on 5954 consecutive patients undergoing valvular procedures at our institution from 1982 to 1996. Stroke was defined as persistent central nervous system deficit, usually with confirmatory CT imaging. Patients were divided into 3 groups according to date of operation: group 1, 1982 to 1986 (n = 1819); group 2, 1987 to 1991 (n = 2022); and group 3, 1992 to 1996 (n = 2113). Chart review was undertaken of all patients who developed stroke (n = 189). Stroke occurred in 3.8% of group 1 patients, 3.3% of group 2, and 2.6% of group 3 (P = 0.120). The decreasing incidence of stroke over time was confirmed by multivariable logistic regression analysis, in which earlier date of operation was an independent risk factor for stroke (P < 0.001). Predictors of stroke identified by multivariable logistic regression were (listed in decreasing order): (1) endocarditis (OR, 3.0; 95% CI, 1.8 to 5.0); (2) age > 74 years (OR, 2.3; 95% CI, 1.5 to 3.7); (3) earlier time period of operation (1982 to 1986: OR, 2.2; 95% CI, 1.5 to 3.2; 1987 to 1991: OR, 1.5; 95% CI, 1.0 to 2.2); (4) urgent timing (OR, 2.0; 95% CI, 1.4 to 2.8); (5) concomitant coronary bypass (OR, 2.0; 95% CI, 1.4 to 2.8); and (6) reoperation (OR, 1.7; 95% CI, 1.2 to 2.4). In more recent years of operation, we found an increasing prevalence of age > 74 years (7.4% in group 1, 9.5% in group 2, and 15.3% in group 3; P < 0.001), urgent timing (11%, 26%, and 34%, P < 0.001), and concomitant coronary bypass surgery (25%, 27%, and 33%; P < 0.001)., Conclusions: The incidence of stroke during valvular surgery has decreased with time, despite an increased prevalence of risk factors. Predictors of stroke suggest 3 major causes (multivariable predictors in parentheses): atherosclerotic emboli (elderly age, concomitant coronary bypass), shock (urgent timing, reoperation), and septic emboli (endocarditis).

Background: Economics has caused the trend of early tracheal extubation after cardiac surgery, yet no prospective randomized study has directly validated that early tracheal extubation anesthetic management decreases costs when compared with late extubation after cardiac surgery., Methods: This prospective, randomized, controlled clinical trial was designed to evaluate the cost savings of early (1-6 h) versus late tracheal extubation (12-22 h) in patients after coronary artery bypass graft (CABG) surgery. The total cost for the services provided for each patient was determined for both the early and late groups from hospital admission to discharge home. All costs applicable to each of the services were classified into direct variables, direct fixed costs, and overhead (an indirect cost). Physician fees and heart catheterization costs were included. The total service cost was the sum of unit workload and overhead costs., Results: One hundred patients having elective CABG who were younger than 75 yr were studied. Including all complications, early extubation (n = 50) significantly reduced cardiovascular intensive care unit (CVICU) costs by 53% (P < 0.026) and the total CABG surgery cost by 25% (P < 0.019) when compared with late extubation (n = 50). Forty-one patients (82%) in each group were tracheally extubated within the defined period. In the early extubation group, the actual departmental cost savings in CVICU nursing and supplies was 23% (P < 0.005), in ward nursing and supplies was 11% (P < 0.05), and in respiratory therapy was 12% (P < 0.05). The total cost savings per patient having CABG was 9% (P < 0.001). Further cost savings using discharge criteria were 51% for CVICU nursing and supplies (P < 0.001), 9% for ward nursing and supplies (P < 0.05), and 29% for respiratory therapy (P < 0.001), for a total cost savings per patient of 13% (P < 0.001). Early extubation also reduced elective case cancellations (P < 0.002) without any increase in the number of postoperative complications and readmissions., Conclusions: Early tracheal extubation anesthetic management reduces total costs per CABG surgery by 25%, predominantly in nursing and in CVICU costs. Early extubation reduces CVICU and hospital length of stay but does not increase the rate or costs of complications when compared with patients in the late extubation group. It shifts the high CVICU costs to the lower ward costs. Early extubation also improves resource use after cardiac surgery when compared with late extubation.

To clarify the controversy over whether the neonatal heart is more or less susceptible to global ischemia than the adult heart, the time interval between the onset of ischemia and the beginning of contracture (TIC) was compared in neonatal (n = 6, 3 to 5 days old) and adult (n = 6, 4 to 5 months old) pig hearts. A comparison of the myocardial concentrations (mumol/g wet weight) of ATP, glycogen, lactate, and glucose-6-phosphate (G-6-P) was also done. The anesthetized animals underwent a sternotomy, and control right ventricular myocardial biopsy samples were taken. The heart of each was rapidly excised and placed in a 37 degrees C substrate-free Krebs-Henseleit bath. A compliant balloon was placed in the left ventricle to record pressure changes. Time to onset and peak TIC were recorded and additional proximal right ventricular biopsy samples were taken. Data were recorded as mean +/- SEM. Results demonstrated that neonatal hearts had a significantly shorter (p less than .05) TIC (29.5 +/- 1.7 min) than adult hearts (43.0 +/- 2.9 min) and exhibited more rapid lactate accumulation (2.5 +/- 0.5 to 22.1 +/- 3.0, p less than .001) and an increase in G-6-P (0.07 +/- 0.03 to 0.34 +/- 0.07, p less than .01) with a nonsignificant decline in myocardial glycogen (23.3 +/- 12.1 to 17.4 +/- 4.0, p greater than .05). Our findings indicate that neonatal hearts are more sensitive than adult hearts to global ischemia, which has potential implications for myocardial protection in pediatric cardiac surgery.