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71.
Summary The release of endogenous catecholamines in aorto-coronary bypass graft patients receiving either 0.5 mg/kg enoximone (n=10), 4.0 mg/kg theophylline (n=10) or saline solution (control,n=10) has been studied, as well as certain haemodynamic parameters. Adrenaline (A) and noradrenaline (NA) concentrations were not significantly changed by the administration of enoximone. Theophylline caused a small increase in NA (+ 40% in the 1st min) and a marked increase in A (approximately + 7000% in the 1st min), which still remained elevated at the end of the investigation period (+ 220% in the 30th min). The major haemodynamic effects of enoximone were a significant increase in cardiac index (CI; + 35%) and a decrease in pulmonary capillary wedge pressure (PCWP; −27%), pulmonary artery pressure (PAP; −21%), RVEDV and RVESV, while the heart rate (HR) remained almost unchanged. The dominant haemodynamic effects of theophylline were an increase in HR (+ 26%; arrhythmia in 3 patients), PAP (+ 22%), and RVEDV (+ 19%), while REVESV (+ 26%), MAP (−16%), CI (−14%), and RVEF (−15%) fell significantly. It is concluded that the haemodynamic actions of enoximone are not mediated by catecholamine release, whereas the adverse cardiovascular effects of theophylline might partly be explained by the significant increase in plasma adrenaline.  相似文献   
72.
成人体外循环术后精神症状原因分析   总被引:9,自引:0,他引:9  
目的 研究成人体外循环手术以后发生精神症状的高危因素。方法 对52例16岁以上的体外循环手术后发生精神症状的病人进行分析。结果 主要表现有认知障碍、情感障碍、意志行为障碍及意识障碍。男女之间无明显差异,而在患者年龄、术前心功能、既往精神病史、监护室监护时间等方面精神病组和健康组间存在显著差异。结论 成人体外循环手术后发生精神症状的高危因素有患者年龄、术前心功能、既往精神病史、心脏病史、监护室停留时间等,应高度重视加强护理和观察。  相似文献   
73.
Background: The gastric bypass operation has evolved since 1966 when it was first introduced. The purpose of this study was to determine the present state of gastric bypass by consensus among the members of the American Society for Bariatric Surgery (ASBS). Method: A questionnaire was sent to all members of the ASBS. Forty-three percent responded reporting over 41,200 cases. Results: Results were analyzed by using χ2 tests with a null hypothesis. Surgeons agreed on several technical aspects, preferring a vertical to a horizontal stapleline; estimating, rather than measuring, the pouch volume at an average of 22 cc. Few surgeons divide the short gastric vessels, and only 25% of surgeons polled use a restrictive ring or band proximal to the gastroenterostomy. Most surgeons calibrate the gastroenterostomy, reporting a preferred average diameter of 12.3 cm. There was no consensus regarding forming the gastroenterostomy, 58% preferring hand-sewn and 42% stapled anastomoses. There was no consensus regarding dividing the gastric pouch from the bypassed stomach: Conclusion: The preferred gastric bypass is vertical, with the pouch estimated at 20-25 cc, and the gastroenterostomy calibrated at 12 mm diameter. The short gastric vessels need not be divided, and restrictive bands or rings are not preferred. This technique of gastric bypass should be used as the control procedure when modifications are tested in future trials. Randomized prospective studies are suggested to probe the benefits of division of the stomach pouch from the bypassed stomach.  相似文献   
74.
Background: Morbid obesity is a serious disease that afflicts over five million Americans, threatening their health with such co-morbidities as diabetes, arthritis, pulmonary failure and stroke. Surgery is the only effective therapy, providing long-term control of weight, diabetes, pulmonary failure, and hypertension for as long as 14 years. Because the operation presents a major expense, this study examined whether X-ray examination of the gut could be omitted safely as a cost-saving measure. Methods: The records of 814 consecutive morbidly obese patients who underwent gastric bypass were reviewed to determine: (1) whether these individuals had undergone an upper gastro-intestinal (GI) series, and (2) if these studies influenced therapy or caused cancellation or postponement of surgery. Results: Of the 814 patients, 657 (80.7%) underwent a preoperative GI radiography. Of these examinations, 393 (59.8%) were normal, with the following abnormalities in the remaining 264: hiatal hernia, 164; esophageal reflux, 39; Schatzki's ring, 18; small bowel diverticula, four; renal stones, four; malrotation, three; gall stones, two; pyloric ulcer, one; possible pelvic mass, one; calcified leiomyoma, one; and dysphagial lusoria, one. None of these findings resulted in cancellation or a delay in surgery. Conclusions: The upper GI series can be safely omitted from the routine preoperative evaluation of patients undergoing gastric bypass. At a cost of $741.00 per examination, this change represents significant potential savings. Similar evaluations of other routine preoperative tests may well provide a better basis for the evaluation of these complex patients.  相似文献   
75.
Objective. Tympanic temperature can be obtained instantaneously using an infrared emission detection (IRED) thermometer. Its accuracy has been documented in a variety of clinical settings, but its performance at low body temperatures is still unknown. In this study we evaluated its performance during coronary artery revascularization surgery in which mild hypothermic cardiopulmonary bypass (CPB) was used. Methods. Thirty adult patients undergoing coronary artery bypass graft surgery were enrolled in the study. Tympanic temperature obtained using IRED thermometry (Tt1) was compared with core temperatures from the esophagus (Te), and venous blood of CPB (Tv) before, during, and after CPB. We also measured tympanic temperature using a thermocouple probe (Tt2) in 16 of the 30 patients in order to study the agreement between the two methods. Values for correlation coefficients and limits of agreement were computed to assess the degree of agreement among the temperatures obtained. Results. The highest agreement with Tv during CPB was obtained from Tt1 (r = 0.94, 0.41 ± 1.73, limits of agreement) and from Te (0.91, 0.36 ± 2.46). Tt1 also showed good agreement with Tt2 during surgery. Conclusions. Infrared tympanic thermometry is a reliable, alternative method to measure tympanic temperature and may be useful to assess core temperature in both normothermic and mild hypothermic conditions.  相似文献   
76.
目的:观察体外静脉转流下原位肝移植围术期酸碱和生化的变化。方法:7例病人行原位肝移植术,在无肝期行体外静脉-静脉转流,监测围术期酸碱和生化指标。结果:(1)与术前相比,pH各期有所下降,但仍维持在正常范围,BE和SBC在转流60分钟及关腹时降低;与转流前期相比。pH以后各期变化不大。术期pH在7.35~7.45范围之内;(2)血糖在各期都升高,血钙降低,体温逐渐降低;(3)血钾在肝血管开放后一过性增高,由3.17mmol/L升至3.53mmol/L。结论;体外静脉转流下原位肝移植术,术中酸碱和生化变化轻微,避免了明显的代谢性酸中毒和高血钾,但体温和血糖变化明显。  相似文献   
77.
Background: Numerous investigators have attempted to identify prognostic indicators for successful outcome following bariatric surgery. The purpose of this study was to determine whether degree of obesity affects outcome in super obese [>225% ideal body weight (IBW)] versus morbidly obese patients (160-225% IBW) undergoing gastric restrictive/bypass procedures. Methods: Since 1984, 157 patients underwent either gastric bypass or vertical banded gastroplasty. Super obese (78) and morbidly obese (79) patients were followed prospectively, documenting outcome and complications. Results: Super obese patients reached maximum weight loss 3 years following bariatric surgery, exhibiting a decrease in body mass index (BMI) from 61 to 39 kg/m2 and an average loss of 42% excess body weight (EBW). Morbidly obese patients had a decrease in BMI from 44 to 31 kg/m2 and carried 39% EBW at 1 year. After their respective nadirs, each group began to regain the lost weight with the super obese exhibiting a current BMI of 45 kg/m2 (61% EBW) versus 34 kg/m2 (52% EBW) in the morbidly obese at 72 months cumulative follow-up. Currently, loss of 50% or more of EBW occurred in 53% of super obese patients versus 72% of morbidly obese (P < 0.01). Twenty-six percent of super obese patients returned to within 50% of ideal body weight (IBW) while 71% of morbidly obese were able to reach this goal (P < 0.01). Co-morbidities and complications related to surgery were similar in each group. Conclusions: Super obese patients have a greater absolute weight loss after bariatric surgery than do morbidly obese patients. Using commonly utilized measures of success based on weight, morbidly obese patients tend to have better outcomes following bariatric surgery.  相似文献   
78.
心脏搭桥术对糖尿病人降糖治疗方案的影响   总被引:1,自引:0,他引:1  
目的 :通过观察 型糖尿病 (DM- )行心脏冠脉搭桥术 (CABG)术后血糖水平的升高到恢复至术前状态的过程 ,从而判断 CABG对 DM- 降糖治疗的影响。方法 :选择 36例 DM- 合并冠心病病人 ,均于体外循环 (CPB)下行心脏搭桥术 ,从术前监测血糖 ,直至术后第七天 ,于术中及术后根据血糖水平适当应用胰岛素 ,观察其对降糖治疗效果及血糖趋于稳定的过程 ,从而判断 CABG对 DM- 血糖的影响。结果 :术中及术后 1~ 3d血糖会较术前明显升高 ,需加用胰岛素助降糖 ,术后 3d血糖渐降 ,第六天趋于稳定 ,第七天恢复至接近术前水平。结论 :DM- ,病人行 CABG术 ,只要围术期有效控制血糖 ,术后血糖基本会逐渐恢复至术前状态 ,对其今后的降糖治疗不会造成严重影响  相似文献   
79.
目的总结冠心病患者行冠状动脉旁路移植术(CABG)和激光心肌血运重建术(TMLR)中的治疗难点、围术期处理要点,以提高冠心病患者的外科治疗效果。方法1997年5月~2006年1月,1405例冠心病患者中在体外循环下行CABG825例,其中单纯CABG666例,CABG+心瓣膜手术98例,CABG+室壁瘤手术55例,CABG+左心房粘液瘤摘除术2例,CABG+室间隔穿孔修补术2例,CABG+升主动脉成形术1例,CABG+纵隔内肿瘤切除术1例;非体外循环下CABG(OPCAB)500例;单纯TMLR30例,CABG+TMLR50例。结果每例移植旁路血管2.9±1.0支。住院死亡42例(3.0%),死亡原因包括出血、心肌梗死、低心排血量综合征、肾功能衰竭、多器官功能衰竭等。术后发生并发症70例,包括出血、低心排血量综合征、心肌梗死、肾功能不全等,均经积极的对症处理后治愈或好转。术前心绞痛(CCS)为~级的1177例患者中,术后1154例(98.0%)改善为0~级。术后随访857例(62.9%),随访时间8.3±2.9个月。随访6个月时788例(91.9%)无心绞痛发作,复查超声心动图提示:左心室射血分数0.66±0.10,较术前提高7.9%,生活质量较术前大为提高。结论CABG已成为治疗冠心病最有效的常规手术,只要能正确掌握适应证,有效地加强围术期管理,便可以扩大手术适应证范围,降低手术死亡率和并发症发生率,提高手术疗效。  相似文献   
80.
由于操作简便、节省人力物力,大鼠体外循环模型的应用愈加广泛。大鼠在小型呼吸机辅助下,应用颈静脉插管入右心房引流血液至贮血瓶,在蠕动移液泵作用下,经膜式氧合器氧合、变温器变温,通过股动脉或尾动脉插管注入动脉系统,建立体外循环回路。有血预充、减少总预充量和维持足够的转流流量是建立大鼠体外循环模型的关键。  相似文献   
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