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81.
Abdominal aortic aneurysms (AAAs) are commonly associated with severe coronary artery disease, but the incidence of associated aortic valve disease and AAAs in the general population is not known. The standard approach for surgical repair of AAAs is a laparotomy, and for aortic valve repair, a full sternotomy; results of both approaches are well documented. However, when AAAs and aortic valve disease occur concomitantly and both are symptomatic, they should be repaired during a combined procedure, with the aortic valve repair performed first. We describe the case of a 75-year-old patient with a symptomatic infrarenal AAA and severe aortic valve stenosis. To avoid an extensive surgical incision and shorten the recovery period, we performed a combined procedure in which we replaced the aortic valve through a ministernotomy and repaired the AAA through a minilaparotomy. The postoperative period was uneventful, and the patient was discharged home 6 days after surgery.  相似文献   
82.
BACKGROUND: Tight perioperative control of blood glucose improves the outcome of diabetic patients undergoing cardiac surgery. Because stress response and cardiopulmonary bypass can induce profound hyperglycemia, intraoperative glycemic control may become difficult. The authors undertook a prospective cohort study to determine whether poor intraoperative glycemic control is associated with increased intrahospital morbidity. METHODS: Two hundred consecutive diabetic patients undergoing on-pump heart surgery were enrolled. A standard insulin protocol based on subcutaneous intermediary insulin was given the morning of the surgery. Intravenous insulin therapy was initiated intraoperatively from blood glucose concentrations of 180 mg/dl or greater and titrated according to a predefined protocol. Poor intraoperative glycemic control was defined as four consecutive blood glucose concentrations greater than 200 mg/dl without any decrease in despite insulin therapy. Postoperative blood glucose concentrations were maintained below 140 mg/dl by using aggressive insulin therapy. The main endpoints were severe cardiovascular, respiratory, infectious, neurologic, and renal in-hospital morbidity. RESULTS: Insulin therapy was required intraoperatively in 36% of patients, and poor intraoperative glycemic control was observed in 18% of patients. Poor intraoperative glycemic control was significantly more frequent in patients with severe postoperative morbidity (37% vs. 10%; P < 0.001). The adjusted odds ratio for severe postoperative morbidity among patients with a poor intraoperative glycemic control as compared with patients without was 7.2 (95% confidence interval, 2.7-19.0). CONCLUSION: Poor intraoperative control of blood glucose concentrations in diabetic patients undergoing cardiac surgery is associated with a worsened hospital outcome after surgery.  相似文献   
83.
Given the deleterious effects of concomitant peripheral arterial disease (PAD) and severe renal disease, a role for aggressive screening and management of PAD in renal failure patients has been suggested. However, limited data exist detailing the impact of PAD on kidney waitlist survival and the potential benefit of transplantation in PAD. Multivariable COX regression and Kaplan–Meier survival models were fit using UNOS data to assess kidney waitlist and post‐transplant five‐yr survival. Compared to PAD?Dial? (no PAD or dialysis) waitlist survival, PAD+Dial? was associated with a 36%, PAD?Dial+ a 95%, and PAD+Dial+ a 190% increased risk of death. A significant survival benefit of kidney transplantation was identified in the PAD population (p < 0.001, HR = 0.440 comparing post‐transplant to waitlist survival). Time to survival benefit (equal mortality between waitlist and post‐transplant population) of kidney transplantation in PAD+ was realized 2.5 times sooner in pre‐emptive transplantation than transplant after dialysis (154 d vs. 381 d), per unadjusted Kaplan–Meier analysis. To our knowledge, this is the first study to demonstrate a survival benefit of kidney transplantation in the setting of PAD. Pre‐emptive transplantation with emphasis on living donation prior to dialysis should be advocated to improve outcomes in this high risk patient population.  相似文献   
84.
OBJECTIVE: To analyse long-term rates of reoperation, myocardial infarction and mortality after transurethral (TURP) and open prostatectomy (open PE) in a nation-wide analysis. MATERIAL AND METHODS: Patients who underwent TURP (n=20,671) or open PE (n=2452) in Austria between 1992 and 1996 entered this study and were followed for up to 8 years. Actuarial cumulative incidences of reoperation (TURP, urethrotomy, bladder neck incision), myocardial infarction and death after 1, 5 and 8 years were calculated. Data were provided by the Austrian Health Institute (OBIG). RESULTS: Actuarial cumulative incidences of a secondary TURP after primary TURP at 1, 5 and 8 years were 2.9%, 5.8% and 7.4%; the respective numbers after open PE 1.0%, 2.7% and 3.4%. The overall incidence of a secondary endourological procedure (TURP, urethrotomy, bladder neck incision) within 8 years was 14.7% after TURP and 9.5% after open PE. The 8 years incidence of myocardial infarction was identical after TURP (4.8%) and open PE (4.9%). In parallel, mortality rates at 90 days (TURP: 0.7%; open PE: 0.9%), one year (2.8% vs. 2.7%), 5 years (12.7% vs. 11.8%) and 8 years (20% vs. 20.9%) was identical after TURP and open PE. CONCLUSIONS: This large-scale, contemporary, nation-wide analysis confirms the higher reoperation rate after TURP compared to open PE. We observed no excess risk of myocardial infarction or death after TURP compared to open PE.  相似文献   
85.
Chronically isolated neocortex develops chronic hyperexcitability and focal epileptogenesis in a period of days to weeks. The mechanisms operating in this model of post-traumatic epileptogenesis are not well understood. We hypothesized that the spontaneous burst discharges recorded in chronically isolated neocortex result from homeostatic plasticity (a mechanism generally assumed to stabilize neuronal activity) induced by low neuronal activity after deafferentation. To test this hypothesis we constructed computer models of neocortex incorporating a biologically based homeostatic plasticity rule that operates to maintain firing rates. After deafferentation, homeostatic upregulation of excitatory synapses on pyramidal cells, either with or without concurrent downregulation of inhibitory synapses or upregulation of intrinsic excitability, initiated slowly repeating burst discharges that closely resembled the epileptiform burst discharges recorded in chronically isolated neocortex. These burst discharges lasted a few hundred ms, propagated at 1-3 cm/s and consisted of large (10-15 mV) intracellular depolarizations topped by a small number of action potentials. Our results support a role for homeostatic synaptic plasticity as a novel mechanism of post-traumatic epileptogenesis.  相似文献   
86.
OBJECTIVE: We have previously reported a limited but favorable experience with a novel sutureless technique for surgical management of postoperative pulmonary vein stenosis occurring after repair of total anomalous pulmonary venous drainage. Because this technique requires integrity of the retrocardiac space for hemostasis, extension of the technique to the primary repair of pulmonary vein anomalies requires evaluation. This analysis reviews our experience with the sutureless technique in patients with postrepair pulmonary vein stenosis, as well as our extension of the technique into primary repair of pulmonary vein anomalies. METHODS: Retrospective univariable-multivariable analysis of all pulmonary vein stenosis procedures and sutureless pulmonary vein procedures over a 20-year period was performed. Cox proportional hazards modeling was used to identify variables associated with freedom from reoperation or death. RESULTS: Sixty patients underwent 73 procedures, with pulmonary vein stenosis present in 65 procedures. The sutureless technique was used in 40 procedures. Freedom from reoperation or death at 5 years after the initial procedure was 49%. Unadjusted freedom from reoperation or death was greater with the sutureless technique for patients with postrepair pulmonary vein stenosis ( P = .04). By using multivariable analysis, a higher pulmonary vein stenosis score was associated with greater risk of reoperation or death. After adjustment, the sutureless repair was associated with a nonsignificant trend toward greater freedom from reoperation or death ( P = .12). Despite the absence of retrocardiac adhesions, operative mortality was not increased with the sutureless technique ( P = .64). Techniques to control bleeding (intrapleural hilar reapproximation) and improve exposure (inferior vena cava division) were identified. CONCLUSION: The sutureless technique for postrepair pulmonary vein stenosis is associated with encouraging midterm results. Extension of the indications for the technique to primary repair appears safe with the development of simple intraoperative maneuvers.  相似文献   
87.
PURPOSE: The 2002 tumor classification for renal cell carcinoma (RCC) classifies pT2 tumors as more than 7 cm in greatest dimension, limited to the kidney. In this study we determined whether a size cutoff point exists within pT2 tumors and whether such subclassification would further improve the accuracy of the current tumor classification. MATERIALS AND METHODS: We studied 544 patients with unilateral, sporadic pT2 RCC treated with radical nephrectomy or nephron sparing surgery between 1970 and 2000. The association of tumor size with death from RCC was examined using martingale residuals from a Cox proportional hazards regression model to determine the optimal size cutoff point. RESULTS: There were 204 deaths from RCC a median of 3.8 years following nephrectomy. Univariately tumor size was significantly associated with death from RCC (risk ratio 1.08, 95% CI 1.04 to 1.13, p <0.001). A scatterplot of tumor size vs expected risk of death per patient suggested that a cutoff point between 9 and 10 cm was appropriate. When adjusted for regional lymph node involvement and distant metastases, the 10 cm cutoff point performed better than the 9 cm point (risk ratio 1.42, 95% CI 1.07 to 1.90, p = 0.017 vs 1.22, 95% 0.86 to 1.72, p = 0.268). Therefore, we propose using a 10 cm cutoff point to subclassify patients into pT2a and pT2b. CONCLUSIONS: Our data suggest that the prognostic accuracy of the 2002 pT2 tumor classification can be further improved by subclassifying patients with tumors greater than 7 and less than 10 cm into a pT2a category, and those with tumors 10 cm or greater into a pT2b category.  相似文献   
88.
In 2 patients with the Jarvik 2000 left ventricular assist device (LVAD), we assessed left ventricular systolic function through pressure-volume loops and E(max) at the beginning and end of the support period to potentially predict the possibility of pump removal without transplantation. Immediately before LVAD implantation and explantation, pressure and volume measurements were made with catheters and echocardiography, respectively, the E(max) being calculated from the slope of the pressure-volume loops, and the left ventricular ejection fraction (LVEF) being estimated by echocardiography. Transplantation was performed after 14 and 62 days, respectively, during which the LVEF increased by 75% (from 12% to 21%) in Patient 1 and remained unchanged (from 16% to 18%) in Patient 2, whereas the E(max) increased from 0.63 and 0.42 mm Hg/ml, respectively, to 1.31 and 1.07 mm Hg/ml, reflecting a 107% and 155% improvement. In these 2 cases, the E(max) was a more reliable indicator of intrinsic myocardial contractility than was the LVEF.  相似文献   
89.
Background: Tight perioperative control of blood glucose improves the outcome of diabetic patients undergoing cardiac surgery. Because stress response and cardiopulmonary bypass can induce profound hyperglycemia, intraoperative glycemic control may become difficult. The authors undertook a prospective cohort study to determine whether poor intraoperative glycemic control is associated with increased intrahospital morbidity.

Methods: Two hundred consecutive diabetic patients undergoing on-pump heart surgery were enrolled. A standard insulin protocol based on subcutaneous intermediary insulin was given the morning of the surgery. Intravenous insulin therapy was initiated intraoperatively from blood glucose concentrations of 180 mg/dl or greater and titrated according to a predefined protocol. Poor intraoperative glycemic control was defined as four consecutive blood glucose concentrations greater than 200 mg/dl without any decrease in despite insulin therapy. Postoperative blood glucose concentrations were maintained below 140 mg/dl by using aggressive insulin therapy. The main endpoints were severe cardiovascular, respiratory, infectious, neurologic, and renal in-hospital morbidity.

Results: Insulin therapy was required intraoperatively in 36% of patients, and poor intraoperative glycemic control was observed in 18% of patients. Poor intraoperative glycemic control was significantly more frequent in patients with severe postoperative morbidity (37% vs. 10%; P < 0.001). The adjusted odds ratio for severe postoperative morbidity among patients with a poor intraoperative glycemic control as compared with patients without was 7.2 (95% confidence interval, 2.7-19.0).  相似文献   

90.
PURPOSE: The primary tumor classification for renal cell carcinoma (RCC) was updated by the American Joint Committee on Cancer in 2002. To date the new classification has not been validated using an independent group of patients and, therefore, its accuracy for predicting patient outcome is unknown. In the current study we evaluated the 2002 primary tumor classification and compared its predictive ability with that of the 1997 classification. MATERIALS AND METHODS: We studied 2,746 patients treated with radical nephrectomy or nephron sparing surgery for unilateral, sporadic RCC between 1970 and 2000. Cancer specific survival was estimated using the Kaplan-Meier method. The predictive abilities of the 1997 and 2002 classifications were compared using the concordance index. RESULTS: There were 812 deaths from RCC a mean of 3.3 years following nephrectomy. Median followup in patients still alive at last followup was 9 years. Estimated 5-year cancer specific survival rates by the 2002 tumor classification were 97%, 87%, 71%, 53%, 44%, 37% and 20% in patients with pT1a, pT1b, pT2, pT3a, pT3b, pT3c and pT4 RCC, respectively. The concordance index for the association between the 2002 classification and death from RCC was 0.752 compared with 0.737 for the 1997 classification, indicating that the 2002 version contained more predictive ability. CONCLUSIONS: Our data suggest that the 2002 primary tumor classification with pT1 cancers subclassified into pT1a and pT1b provides excellent stratification of patients according to cancer specific survival and it has a predictive ability that is superior to that of the 1997 classification.  相似文献   
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