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21.
Rosendo A. Rodriguez MD PhD Fraser Rubens MD MSc Carlos D. Rodriguez Howard J. Nathan MD 《Journal of neuroimaging》2006,16(2):126-132
OBJECTIVE: The application of intensity thresholds for embolus detection with transcranial Doppler (TCD) can exclude from analysis an unrecognized proportion of high-intensity transient signals (HITS))whose intensities are below the threshold. The lack of consistent threshold criteria between clinical trials may explain part of the discrepancy in the reported HITS counts. We investigated the effect of choosing different thresholds on the sensitivity and specificity of detecting HITS during cardiopulmonary bypass (CPB). METHODS: Two observers independently analyzed TCD recordings from 8 patients under CPB. Doppler signals were classified as true HITS, equivocal HITS, artifacts, and Doppler speckles according to preestablished criteria. The relative intensity of Doppler signals was measured by two different methods (TCD software vs manual). Receiver Operating Characteristic curves determined the optimal threshold for each of the two intensity methods. RESULTS: Reviewers achieved agreement in 96% of 2190 Doppler signals (kappa = 0.90). Relative intensities calculated with the TCD-software method were 3 dB (95% CI: 3.0-3.4) higher than the manual method. The optimal threshold was found at 10 dB (sensitivity: 99%; specificity: 90.8%) with the software method and at 7 dB with the manual method (sensitivity: 96%; specificity: 83%). The use of an intensity threshold 2 dB higher than the optimal increased the rejection of true HITS by 8% and 14%, respectively. CONCLUSIONS: Using intensity thresholds higher than the optimal for embolus detection decreases HITS counts. Choosing a threshold depends on the type of method used for measuring the signal intensity. Uniform threshold criteria and comparative studies between different Doppler devices are necessary for making clinical trials more comparable. 相似文献
22.
Objestive Systemic inflarmmation may be triggered by injury, hypothermia, ischemia-reperfusion and the contact of the blood with foreign body during cardiopulmonary bypass (CPB). To determine the application values of gene chip technique in the clinical practice and the study of cardiovascular stagery, as well as to provide clues to the study of inflammatory responess during CPB, microarry for gene expression profiles was used to identify the differences in the gene expression of myocardium between pre-and post- CPB. Methods Six adult patients who underwent CPB from March to May in 2003 were involved. Samples of right atrium were col- lected before and at immediate end of CPB. BD AtlasTM cDNA Expression Arrays was used to identify the differences in the gene ex- pression of cytokines. The results were compared with that of semi-quantative RT-PCR. Resellts The mean age of 6 patients (5 males and 1 female) was (32.67± 11.72) years. The baseline heart function was gradeⅡin 3 cases and grade Ⅲ in 3 other cases. The baseline left ventricular ejection fraction(LVEF)was (58.17±7.91)%. The mere duration was (91.67±43.88) minutes for CPB and was (58.67±43.46) minutes for aorta blocking. The minimum nasopharynx/rectal temperture was (29.37±1.90)℃/ (32.15±1.52)℃. Gene expression profiles of cytokines in the myocardium pre- and post-CPB were analysed successfully. The ex- pression of IL-6, IFN-γ,Wnt5a, TNFRSF1B, a member of tumor necrosis factor receptor superfamily, PIGF and MFNG in the myo- cardium were unpregulated after CPB. Conclusion Microarray technique is applicable in the study of cytokines changes dying CPB. cDNA microarray identified pleliminarily the differences in the gene expression between pre- and post-CPB. These genes may be in- valved in inflammation and other psthophysiological responses incuced by CPB. The myocardiym is probably one of the major sources of cytokines during CPB. Further study may be helpful in understanding the llngthe development of inflammation during CPB, and eventually, reducing the post-operative complications. 相似文献
23.
Tetsuro Sano Munetaka Masuda Shigeki Morita Hisataka Yasui 《The Japanese Journal of Thoracic and Cardiovascular Surgery》2006,54(4):149-154
OBJECTIVE: It is well documented that cardiopulmonary bypass (CPB) severely impairs cellular immunity. The objective of this study was to investigate the effect of prostaglandin E1 (PGE1) on cellular immunity after CPB. METHODS: Patients who underwent elective cardiac surgery were randomly divided into the PGE1 group (n=12) and the control group (n=12). In the PGE1 group, PGE1 was administered at 20 ng/kg/min from just after the induction of anesthesia to the end of surgery. Peripheral blood mononuclear cells (PBMCs) were taken before anesthesia and on postoperative days 1, 3 and 7 (POD 1, POD 3 and POD 7). Proliferation responses of T cells to phytohemagglutinin (PHA) and pure protein derivative (PPD) antigen were measured as indicators of cellular immunity. RESULTS: PGE1 significantly attenuated the impairment of both PHA and PPD response after cardiac surgery on POD 1 (PHA response, 30 +/- 21% vs. 53 +/- 32%, control vs. PGE, p=0.048; PPD response, 18 +/- 21% vs. 39 +/- 27%, control vs. PGE, p=0.046). The reduced glutathione content of PBMCs in the control group was significantly decreased on POD 1. CONCLUSION: PGE1 attenuated the impairment of cellular immunity after cardiac surgery with CPB by reducing oxidative stress on PBMCs. 相似文献
24.
中西医结合治疗Leriche综合征78例 总被引:1,自引:1,他引:0
目的:总结中西医结合治疗Leriche综合征的方案.方法:回顾性总结Leriche综合征的临床治疗78例,均行人工血管主股或主髂动脉转流手术,术后静脉应用低分子右旋糖酐、复方丹参注射液和维脑路通.结果:手术结束后均能触及股动脉和动脉搏动,手术后7 d,患肢缺血症状均得到改善.手术后3月,患肢缺血症状消失,64例阳痿现象得到改善.彩色超声血管吻合口及人工血管内均未见血栓.结论:人工血管主股动脉转流或主髂动脉转流是治疗Leriche综合征较好的手术方案,围手术期合理应用扩血管、祛聚、活血化瘀药物,同时及时处理伴发疾病是提高临床治愈率和提高远期疗效的关键. 相似文献
25.
Dr. Arni Raghavendrarao Raghuram M.Ch. Subbiah Kumar MD Kathamuthu Balamurugan DA Arulmurugan DA Ramiah Krishnan M.Ch. Perichiappan Sivakami BS Eluvathingal Varghese John M.Ch. 《Indian Journal of Thoracic and Cardiovascular Surgery》2006,22(3):178-181
Background Beating heart surgery has now become the commonest technique of doing Coronary Artery Bypass Graft Surgery (CABG) in our country.
It is being used even in such high risk situations like diffuse coronary disease and Critical Left Main stem Stenosis (LMCS)
with good results. The aim of this study is to retrospectively review our results in Off-Pump Coronary Artery Bypass Surgery
(OPCAB) in patients with critical left main stem stenosis.
Methods This study is a retrospective analysis of the data of patients who underwent primary coronary artery bypass surgery. During
the period from April 2003 to September 2005 a total of 64 patients underwent OPCAB procedure for critical LMCS. During the
same period 10 patients underwent CABG on Cardio Pulmonary Bypass (CPB). The age range was 36–77yrs. The sex distribution
was M: F 53∶10. Ten patients were done as emergency. 2 of them were on Intra Aortic Balloon Pump (IABP) support preoperatively.
10 patients were high risk with a Euro score of ≥5.
Results Left Internal Mammary Artery (LIMA) was used in 78% of cases. Average grafts per patient was 2.96. The median ventilation
time was 5.91 hrs. New IABP insertion in postoperative period was required in 1 patient. One patient was reexplored for bleeding.
There was one perioperative myocardial infarction. 57% of patients did not need any blood transfusion. There was no conversion
to CPB. There was no operative mortality. Inotropes were used in ten cases.
Conclusions OPCAB is a safe method of revascularization in patients with critical LMCS. Preoperative IABP is useful in patients with cardiogenic
shock. However, there is a place for CPB in patients needing additional procedures like Mitral Valve repair (MV repair) or
Dor's procedure or when the vessels are very diffusely diseased. Those patients who are unstable despite IABP support may
be managed by Beating heart On Pump (BHOP) technique. 相似文献
26.
目的报告2002年4月至2004年12月67例冠状动脉旁路移植手术(CABG).方法男性58例,女性9例,年龄41~76岁,平均58.5岁.合并二尖瓣病变同期手术3例,3支血管病变39例,2支血管病变28例.采取体外循环下手术(on-pump-CABG)和非体外循环下手术(off-pump-CABG)两种方式,各有其适应指征.结果全组死亡1例,其余治愈出院,随诊1~18个月,心绞痛消失,疗效满意.结论冠状动脉旁路移植手术安全,有很好的发展前景. 相似文献
27.
目的:研究异丙酚和异氟醚对非体外循环搭桥术患者围术期炎性与抗炎性细胞因子平衡的影响。方法:择期非体外循环搭桥患者50例,随机分为2组。异丙酚组微量泵输入剂量为4~6mg·kg-·1h-1,异氟醚组吸入浓度为1%~1.5%。检测诱导前、打开心包、旁路血管开放30min,术后2h、24h血清白细胞介素6(IL-6)、白细胞介素10(IL-10)和肿瘤坏死因子α(TNF-α)的浓度。结果:2组患者旁路血管开放后IL-6浓度较术前升高(P<0.01),术后2h达高峰;术后2h异氟醚组高于异丙酚组(P<0.05)。IL-10浓度变化趋势与IL-6相似,旁路血管开放后、术后2h和24h异丙酚组高于异氟醚组(P<0.05)。2组患者TNF-α水平均无显著变化。结论:异丙酚麻醉促进IL-10的产生,抑制IL-6的产生,控制术中应激反应异丙酚优于异氟醚。 相似文献
28.
Background: The bariatric patient exists in dynamic relationship with family members and friends who have considerable influence
upon the patient and his or her surgical outcome. When family members and friends behave as intimate saboteurs, they attempt
to hamper, hurt, or subvert the bariatric patient's goal of achieving and maintaining a healthy body weight. Successful or
not, intimate saboteurs provide significant treatment challenges for the patient and the treatment team. Methods and Patients:
Patient profiles provide examples of intimate sabotage. The psychological construct of Family Systems Theory is used as a
plausible explanation for the sabotage of friends and family. Conclusions: Multidisciplinary professionals treating the bariatric
patient must be aware of the critical influence of intimate saboteurs and the tactics they use to sabotage. Treatment guidelines
recommended by Family Systems Theory are presented as strategies to mitigate the influence of intimate saboteurs. 相似文献
29.
A Decade of Change in Obesity Surgery 总被引:4,自引:0,他引:4
Edward E Mason MD PhD Shenghui Tang MS Kathleen E Renquist BS Dwight T Barnes Joseph J Cullen MD Cornelius Doherty MD James W Maher MD 《Obesity surgery》1997,7(3):189-197
Background: The International (formerly National) Bariatric Surgery Registry began collecting data in January 1986. The aim
of this study was to examine changes in the practice of surgical treatment of severe obesity that occurred during the decade
of 1986 through 1995, as observed in the IBSR data. Methods: All data submitted to the IBSR during the decade were transferred
to the IBM mainframe computer for analysis. Characteristics of operative type populations were compared over time using analysis
of variance (ANOVA) for age, body mass index (BMI), operative weight and Chi-square (χ2) test for gender. Results: There has been a steady increase over the decade in mean patient weight. The operations used have
changed from predominantly ‘simple’ operations to more frequent use of ‘complex’ operations. Within the categories of ‘simple’
and ‘complex’, an increase in the variety of operations occurred. As a group, patients with ‘simple’ operations have been
heavier, more often male and public pay patients than those who have undergone ‘complex’ operations. One year weight loss
was greater for Roux-en-Y gastric bypass (RGB) than vertical banded gastroplasty (VBG), but follow-up rates were too low to
study the relative merits of the operations used. The reported incidence of operative mortality and serious complications
(leak with peritonitis, abscess and pulmonary embolism) remained low. Conclusions: These observations and their implications
can be summarized in three statements which relate to action for improved patient care in the beginning of the new century:
(1) increasing weight of candidates for surgical treatment during this decade indicates the need for earlier use of operative
treatment before irreversible complications of obesity can develop; (2) low risk of obesity surgery, decreasing postoperative
hospital stay, and early weight control support the continued and increased use of surgical treatment; (3) continued widespread
use of both ‘simple’ and ‘complex’ operations with increased modifications of standard RGB and VBG procedures emphasizes the
need for standardized long-term data and analyses regarding both weight control and postoperative side-effects. 相似文献
30.
对13例体外循环病人进行了观察,发现体外循环后TXB2/6-keto-PGF1α显著增高,表明体外循环使血小板受损,而血小板受损是体外循环后失血的主要原因之一。 相似文献