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61.
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   
62.
OBJECTIVE: Mitral regurgitation is a frequent finding in patients with end-stage cardiomyopathy predicting poor survival. Conventional treatment consists medical treatment or cardiac transplantation. However, despite severely decreased left ventricular function, mitral annuloplasty may improve survival and reduce the need for allografts. METHODS: From January 1996 to July 2002, 121 patients with severe end-stage dilated (DCM) or ischemic cardiomyopathy (ICM), mitral regurgitation > or =2, and left ventricular ejection fraction < or =30% underwent mitral valve annuloplasty using a flexible posterior ring. DCM was diagnosed in 30 patients (25%), whereas ICM was found in 91 patients (75%). Concomitant tricuspid valve repair was performed in 14 (46.6%) patients in the DCM, and in 11 (12%) in the ICM group (P=0.0001), coronary artery bypass grafting in three (10%) in the DCM, and in 78 patients (86%) in the ICM group (P<0.00001). The mean follow-up time was 567+/-74 days in the DCM and 793+/-63 days in the ICM group (ns). RESULTS: Early mortality was 6.6% (8/121), and was equal for both groups. Improvement in NYHA class (DCM 3.3+0.1-1.8+/-0.16; ICM from 3.2+0.04 to 1.7+/-0.07) were equal between groups after 1 year. Seventeen (15%) late deaths occurred during the follow-up period. There was no difference in the 2-year actuarial survival between groups (DCM/ICM 0.93/0.85). Risk factors for mitral reconstruction failure, defined as regurgitation > or =2 after 1 year, were preoperative NYHA IV in the DCM group (P=0.03), a preoperative posterior infarction (P=0.025), decreased left ventricular function (P=0.043), larger ring size (P=0.026) and preoperative renal failure (P=0.05) in the ICM group. Risk factors for death were larger ring size (P=0.02) and an increased LVEDD (P=0.027) in the DCM group and the postoperative use of IABP (P=0.002), renal failure (P=0.001), and a larger preoperative LVESD (P=0.035) in the ICM group. CONCLUSION: Mitral reconstruction with a posterior annuloplasty using a flexible ring is effective in patients with severely depressed left ventricle function and has an acceptable operative mortality. Mid-term results are superior to medical treatment alone and comparable to cardiac transplantation.  相似文献   
63.
Background: G-protein activation mediates inhibition of N-type Ca2+ currents. Volatile anesthetics affect G-protein pathways at various levels, and activation of G-proteins has been shown to increase the volatile anesthetic potency for inhibiting the electrical-induced contraction in ileum. The authors investigated whether isoflurane inhibition of N-type Ba2+ currents was mediated by G-protein activation.

Methods: N-type Ba2+ currents were measured in the human neuronal SH-SY5Y cell line by using the whole cell voltage-clamp method.

Results: Isoflurane was found to have two effects on N-type Ba2+ currents. First, isoflurane reduced the magnitude of N-type Ba2+ currents to a similar extent (IC50 ~ 0.28 mm) in the absence and presence of GDP[beta]S (a nonhydrolyzable GDP analog). Interestingly, GTP[gamma]S (a nonhydrolyzable GTP analog and G-protein activator) in a dose-dependent manner reduced the isoflurane block; 120 [mu]m GTP[gamma]S completely eliminated the block of 0.3 mm isoflurane and reduced the apparent isoflurane potency by ~ 2.4 times (IC50 ~ 0.68 mm). Pretreatment with pertussis toxin or cholera toxin did not eliminate the GTP[gamma]S-induced protection against the isoflurane block. Furthermore, isoflurane reduced the magnitude of voltage-dependent G-protein-mediated inhibition of N-type Ba2+ currents, and this effect was eliminated by pretreatment with pertussis toxin or cholera toxin.  相似文献   

64.
Abstract:  Left ventricular assist device (LVAD) implantation in end-stage heart failure patients is frequently associated with hemorrhagic complications requiring reoperation. The preoperative coagulopathic profile includes prolonged prothrombin time (PT), partial thromboplastin time (PTT), and bleeding time; platelet dysfunction; decreased coagulation factor activity; and increased inflammatory markers. We compare outcomes in LVAD patients treated with preoperative plasma exchange with concurrent, nonrandomized control patients. We reviewed data from 68 consecutive elective patients who received LVADs at our institution. Thirty-five received LVADs after preoperative plasma exchange (replacement of one plasma volume of fresh frozen plasma), and 33 received LVADs without plasma exchange. Groups were comparable in age, sex, body weight, New York Heart Association class, intra-aortic balloon pump insertion, cardiac index, pulmonary capillary wedge pressure, creatinine, total bilirubin, hemoglobin levels, PT, international normalized ratio, PTT, and platelet count. Early mortality was lower in the plasma exchange group (0% [0/35] vs. 18% [6/33], P  = 0.026), and postoperative chest tube drainage decreased by 33% ( P  = not significant). Blood transfusion requirements were similar.Perioperative mortality decreased in patients treated with plasma exchange before LVAD implantation.  相似文献   
65.
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   
66.
BACKGROUND: The role of local excision for pT2 distal rectal cancer has been challenged because of the observation of high rates of lymph node metastases and local failure. However, neoadjuvant chemoradiation therapy (CRT) has led to increased local disease control and significant tumor downstaging, possibly decreasing rates of lymph node metastases. In this setting, a possible role for local excision of ypT2 has been suggested. METHODS: A total of 401 patients with distal rectal cancer underwent neoadjuvant CRT. Tumor response assessment was performed after at least 8 weeks from CRT completion. One hundred and twelve patients with complete clinical response were not immediately operated on and were excluded from the study, and 289 patients with incomplete clinical response were managed by radical surgery. Patients with final pathological stage ypT2 were analyzed to determine the risk of unfavorable pathological features that could represent unacceptable risk for local failure after local excision. RESULTS: Eighty-eight (30%) patients had ypT2 rectal cancer. Final ypT status was not associated with pretreatment radiological staging (p = 0.62). ypT status was significantly associated with the risk of lymph node metastases, risk of perineural and vascular invasion, and recurrence (p = 0.001). Lymph node metastases were present in 19% of patients with ypT2 rectal cancer. The risk of lymph node metastases in ypT2 was associated with the presence of perineural invasion (47% vs 4%; p = <0.001), vascular invasion (59% vs 6%; p < 0.001), and decreased mean interval CRT surgery (12 vs 18 weeks; p < 0.001), but not with mean tumor size (3.2 vs 3.1 cm; p = 0.8). Disease-free and overall survival rates were significantly better for patients with ypT2N0 (p = 0.02 and 0.006, respectively). Fifty-five (63%) patients with ypT2 had at least one unfavorable pathological feature for local excision (lymph node metastases, vascular or perineural invasion, mucinous type or tumor size >3 cm). CONCLUSION: Lymph node metastases were present in 19% of patients with ypT2 and were significantly associated with poor overall and disease-free survival rates. The risk of lymph node metastases could not be predicted by radiological staging or tumor size. Radical surgery should be considered the standard treatment option for ypT2 rectal cancer after CRT.  相似文献   
67.
Blute ML  Boorjian SA  Leibovich BC  Lohse CM  Frank I  Karnes RJ 《The Journal of urology》2007,178(2):440-5; discussion 444
PURPOSE: Surgical resection for patients with renal cell carcinoma and venous tumor thrombus may require interruption of the inferior vena cava using a Greenfield filter, ligation or resection. We describe the indications, technique, complications and outcomes of vena caval interruption during nephrectomy with tumor thrombectomy. MATERIALS AND METHODS: We identified 160 patients treated for level II-IV tumor thrombus at our institution between 1970 and 2004. Operative reports were reviewed to establish vena caval interruption. All patients who underwent interruption were assessed for postoperative disability according to the American Venous Forum International Consensus Committee. RESULTS: Vena caval interruption was performed in 40 of 160 cases (25%), including 14 level II, 10 level III and 16 level IV thrombi. A total of 34 patients (85%) were symptomatic at presentation. A Greenfield filter was deployed before cavotomy closure in 4 of 160 patients (2.5%) for bland thrombus of the infrarenal vena cava. Vena caval ligation was used for bland thrombus that completely occluded the infrarenal vena cava in 23 of 160 patients (14.4%), while segmental vena caval resection was performed for tumor thrombus growing into the wall of the vena cava or for tumor thrombus that interfaced with bland thrombus in 13 of 160 (8.1%). Postoperatively no case was class 3 disability, 12 of 40 (30%) were class 2, 12 of 40 (30%) were class 1 and 16 of 40 (40%) showed no disability. CONCLUSIONS: The need to interrupt the inferior vena cava is not infrequent in patients undergoing radical nephrectomy and tumor thrombectomy, and it may be well tolerated postoperatively. Management should be based on the degree of venous occlusion and the presence of bland thrombus.  相似文献   
68.
BACKGROUND : The new generation of breast implants has an anatomic shape. These implants are made with a textured shell and filled with a cohesive silicone gel. Available since 1993 except in the United States, these implants are gaining in popularity for breast enlargement and reconstruction. This prospective, randomized, controlled, and blinded study was designed to compare mid- and long-term results with the use of cohesive gel-filled implants from two different manufacturers: Style 410 of the McGhan brand (MG) made by Allergan and Vertex made by Eurosilicone (ES). METHODS: From May 1997 to May 1999, 80 women underwent breast augmentation: 40 with Style 410 implants (MG) and 40 with Vertex implants (ES). All surgeries were performed by the same surgeon (I.N.). Another physician (G.J.) interviewed and examined 64 of these women (80%) 4 to 6 years (median, 5 years) after implantation. In addition, 10 patients responded to the same questionnaire and were interviewed by phone, bringing the follow-up rate to 92.5%. RESULTS: Overall, satisfaction was high, with 98.6% of the patients evaluated after 4 to 6 years "very satisfied" or "satisfied" with the result in general. Approximately 20% of the patients who responded judged their breasts to be firmer than desirable. Breast augmentation classification (BAC) was used to grade the breast firmness of the 64 patients examined by G. J. At examination, 24% of patients had soft breasts, 53% had slightly firm breasts, and 23% had moderately firm breasts. That last category also was classified as capsular contracture. No patient was graded as having very hard breasts (BAC 4). Skin sensitivity of the breast adjacent to the incision was altered for 25% of the patients. The implant rotated in four patients (5%). Breast firmness, implant palpability, nipple sensitivity, and skin sensitivity were further analyzed by implant location (submuscular vs subglandular) and implant size (volume). Frequency of the breast asymmetries and the impact of augmentation on asymmetric breasts also was studied. All these analyses were performed with the entire pool of examined patients who answered the follow-up questionnaire. Data also were analyzed by distinguishing between results of the two each implant manufacturers. The results showed no difference between the Eurosilicone and McGhan implants except for the self-evaluation of "breast consistency" by the patient. A higher percentage of patients with the Vertex implants than with the McGhan implants reported that their breast was "firmer than desired." CONCLUSIONS: Breast augmentation with anatomic, textured, cohesive silicone gel-filled implants is a reliable procedure with consistently good results. The results also show that candidates for breast enlargement should be informed that their implanted breast may feel firmer than their natural breasts. They also may experience reduced sensation of their nipple or breast skin.  相似文献   
69.
70.
IntroductionIntraoperative hypothermia (IOH) has been suggested to adversely impact outcomes following surgery. The objective of this study was to evaluate the association between IOH and survival following radical cystectomy (RC).MethodsPatients who underwent RC for bladder cancer from 2003 to 2018 were identified in our cystectomy registry. Intraoperative temperatures were extracted from the anesthesia record. IOH was defined as a median intraoperative temperature <36°C, and severe IOH as ≤ 35°C. Time under 36°C was assessed as a continuous variable. Recurrence-free survival (RFS), cancer-specific survival (CSS), and overall survival (OS) were estimated using the Kaplan-Meier method. Associations between IOH and outcomes were assessed with multivariable Cox proportional hazards models.ResultsA total of 852 patients were identified, among whom 274 (32%) had IOH. Median follow up among survivors was 4.9 years (IQR 2.4–8.7), during which time 483 patients died, including 343 from bladder cancer. Two-year survival was not significantly different between patients with and without IOH (CSS: 74% vs. 71%, P= 0.31; OS: 68% vs. 67%, P= 0.13). Following multivariable adjustment, neither IOH nor time under 36°C was significantly associated with survival. A total of 37 patients (4.3%) had severe IOH. These patients were observed to have significantly lower 2-year OS (56% vs. 68%, P= 0.005); however, this association did not remain statistically significant after multivariable adjustment (P= 0.92).ConclusionIOH was not independently associated with survival following RC. These data do not support IOH as a prognostic factor for cancer outcomes among patients undergoing RC.  相似文献   
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