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41.
Global coronary blood flow and metabolism were measured in seven patients on the first postoperative day following coronary revascularization to test the hypothesis that tracheal extubation produces adverse haemodynamic responses akin to those observed during tracheal intubation. Regional coronary flow and metabolic measurements were made in five of the seven patients. Extubation from a continuous positive airway pressure (CPAP) of 5 cm H2O was associated with a statistically significant rise in cardiac index from 3.44 ± 0.23 L · min-1 · m-2 to 3.73 ± 0.15L·min-1 ·m-2 related to an increase in stroke index, without significant changes in heart rate, mean arterial and pulmonary capillary wedge pressure. Consequently the changes in myocardial oxygen consumption (8.52 ± 0.55 to 8.85 ± 0.93 ml · min-1) and coronary blood flow (172 ± 18 to 179 ± 17 ml·min-1) were less prominent than those reported during intubation, where substantial rises in myocardial oxygen consumption and coronary flow occurred. Two patients experienced cardiac lactate production but there were no changes in systemic or coronary haemodynamics, nor were there clinical or electrocardiographic signs of ischaemia. We conclude that extubation does not appear to be associated with adverse systemic or coronary haemodynamic responses in patients following coronary bypass grafting. However, the revascularized myocardium may remain vulnerable to anaerobic metabolism in the immediate postoperative period. Pour savoir si comme ľintubation, ľextubation de la trachée provoque des perturbations hémodynamiques, on a mesuré le métabolisme et la circulation coronarienne globale chez sept patients, au lendemain ďun pontage aorto-coronarien. On a aussi calculé les valeurs régionales de ces mêmes variables pour cinq ďentre eux. Ľindex cardiaque de 3.44 ± 0.23 L · min-1 · m-2 sous pression positive en respiration spontanée (CPAP) de 5 cm. H2O s’est élevé à 3.73 ± 0.15 L · min-1 · m-2 post-extubation avec une augmentation significative du volume ďéjection. La fréquence cardiaque et les pressions artérielles moyennes et capillaires pulmonaires n’ont pas changé. Ainsi ľaugmentation de la consommation ďoxygène du myocarde de 8.52 ± 0.55 à 8.85 ± 0.93 ml · min-1 et celle du flot coronarien de 172 ± 18 à 179 ± 17 ml · min-1 ont été moindres que celles, importantes, déjà observées lors de ľintubation. On a noté chez deux patients une production de lactate par le myocarde, sans changement de ľhémodynamic systémique et coronarienne non plus que de signe clinique ou électrocardiographique ďischémie. Donc, après un pontage coronarien, ľextubation ne semble pas causer ďeffet néfaste sur les circulations systémique et coronarienne, toutefois, le myocarde revascularisé peut demeurer sensible au métabolisme anaérobique.  相似文献   
42.
针刺对血浆骨动素,生长抑素及内皮素的影响及其意义   总被引:14,自引:2,他引:12  
探讨针刺调整调整胃肠功能机理中胃肠激素的作用。方法:对40名健康人对进行针刺胃肠相关穴位试验,随机分4组,即天枢组,巨虚组,非穴位刺激组及空白组。各针刺组均观察针刺前,中,后6次血浆MTL,SS及ET水平的动态变化,空白组不行针刺,只观察同一时间蚋MTL,SS及ET水平的自然波动。  相似文献   
43.
44.
本文阐述了奥美拉唑(Omeprazole)治疗急性上消化道大出血80例与法莫替丁(Famotidine)治疗上消化道大出血50例比较,前者有效率明显高于后者。提示奥美拉唑治疗急性上消化道大出血效果好,无副作用,减少了手术率、死亡率,是一种有效的止血药物。  相似文献   
45.
Omeprazole is a substituted benzimidazole that causes dose-dependent intracellular inhibition of gastric acid secretion in humans. This double-blind study examined the effect of omeprazole in decreasing gastric acidity and gastric residual volume in outpatient adults. Unpremedicated outpatients, ASA I-III, 18 years or older (n = 17), were randomly assigned to receive omeprazole 80 mg, or placebo by mouth the night before scheduled elective outpatient surgery. The patients were fasted for 8 h prior to surgery. After the patient was anesthetized, an orogastric tube was inserted with proper placement verified by auscultation for gastric sounds. Gastric residual contents were withdrawn into a Luken's trap, and pH was then determined and gastric volume indexed to weight (ml.kg-1). Data were analyzed by a t-test, with P less than 0.05 considered statistically significant. Patient characteristics of both groups were similar. There was a statistically significant difference between the two groups for pH (P = 0.02), but not between the two groups for gastric volume indexed to weight (P = 0.07).  相似文献   
46.
OBJECTIVE: Surgery for Crohn's disease (CD) is associated with a high recurrence rate and quality of life (QOL) in these patients is controversial. The aim of this study was to assess QOL in patients after laparoscopic and open surgery for CD by two different validated instruments, a generic nonspecific score and a specific gastrointestinal QOL index. PATIENTS AND METHODS: Patients with CD who underwent elective laparoscopic or open ileocaecal resection with primary anastomosis between 1992 and 2000 were followed for recurrence and surgery-related complications. QOL was assessed by the SF-36 Health Survey containing a mental (MCS) and a physical (PCS) component summary score and by the Gastrointestinal Quality of Life Index (GIQLI) developed by Eypasch. RESULTS: Thirty-seven patients with a mean age of 48.8 +/- 18.4 years including 23 females and 14 males were evaluated at a mean follow-up of 42.6 +/-25.8 months (minimum of 8 months). Twenty-one (57%) patients underwent laparoscopic resection and 16 (43%) open surgery. Both groups were well matched for age, gender, ASA class and body mass index. Fourteen (38%) patients developed recurrent disease and 3 (8%) had postoperative incisional hernias. Overall, QOL scores were 103 +/- 26.8 for the GIQLI, 47.2 +/- 11.8 for the PCS, and 49.2 +/- 11.5 for the MCS. The GIQLI correlated well with the SF36, correlation coefficient = 0.68 for GIQLI vs PCS (95% CI, 0.41,0.95) and 0.67 for GIQLI vs MCS (95%CI, 0.39, 0.95), respectively. When compared to the general US population, mean GIQLI scores (-13.8, P = 0.002) and mean PCS scores (-4.7, P = 0.001) were significantly lower in these patients than in healthy individuals. In a multivariate analysis of impact factors on QOL, recurrence within the follow-up period was the single significant determinant reducing the PCS (-35.1, P = 0.026) and the GIQLI (-36.1, P = 0.018). CONCLUSION: QOL is significantly reduced in patients with CD at long-term follow-up after both laparoscopic and open surgery. Recurrence is the only factor adversely affecting QOL of CD patients in remission irrespective of the operative technique applied.  相似文献   
47.
A 52‐year‐old Japanese woman who presented with gastrointestinal (GI) bleeding underwent a proximal gastrectomy for a gastrointestinal stromal tumor (GIST) with a foveolar hyperplasia at the apex of the tumor, 4.5 cm in size, located in the upper body of the stomach. Although GIST are often asymptomatic and are found only incidentally, clinical symptoms such as bleeding, abdominal pain, or obstruction, occasionally lead to a premorbid diagnosis. When submucosal tumors present GI bleeding, the source of the bleeding usually is an ulceration of the mucosa over the tumor. However, in the present study, it was thought that the bleeding originated from the region of foveolar hyperplasia.  相似文献   
48.
Attempts have been made to culture the mucosa from various parts of the gastrointestinal tract. In this study, using an explant culture method, epithelial cells have been successfully cultured from all major regions of the gastrointestinal tract. The success rate, as judged by outgrowth of epithelial cells for at least 4 weeks, varied with the tissue studied with 19/50 colonic biopsies, 5/11 small intestinal biopsies, 9/12 stomach biopsies and 42/47 gallbladder biopsies yielding outgrowth of epithelial cells. Differentiation of the epithelial cells along the mucus cell pathway could be demonstrated on the monolayer cultures using Periodic acid Schiff or Alcian blue staining. Because the cultures were very heterogeneous and many morphological cell types were present in most cultures, differentiation along the other known differentiation pathways of the gastrointestinal mucosa, such as development of absorptive cells and endocrine cells, could not be excluded.
The problem of bacterial contamination, which has hindered previous studies on tissue from these sites, was overcome by decontaminating the biopsy by soaking in dilute sodium hypochlorite (0.04%).  相似文献   
49.
50.
BACKGROUND: Caecal intubation is a necessary step in the complete endoscopic evaluation of the colon. Studies have estimated that experienced colonoscopists may fail to reach the caecum in up to 10% of cases. AIMS: To evaluate the utility of the double balloon enteroscope used for complete examination of the colon in patients with incomplete standard colonoscopy. PATIENTS: Twenty consecutive patients with incomplete colonoscopies within the Veterans Affairs Palo Alto Health Care System. Mean age of 66 years (S.D.+/-12 years, range 46-84), 16 men. METHODS: Prospective single-centre case series on the caecal intubation rate using standard double balloon enteroscope technique in patients with previous incomplete conventional colonoscopy. RESULTS: Use of the standard double balloon enteroscope technique permitted complete colonoscopy to be achieved in 95% of the patients (19/20). Seven patients (35%) had significant pathology beyond the extent of the prior incomplete colonoscopy. We performed endoscopic mucosal resection, polypectomy or biopsy. The mean time to reach the caecum was 28 min (S.D.+/-20 min, range 6-90 min). The sedation was similar to conventional colonoscopy. No complications occurred. CONCLUSIONS: The double balloon enteroscope technology and technique can be used to complete examination of the colon in patients who were referred because of incomplete standard colonoscopy.  相似文献   
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