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31.
PURPOSE OF THE STUDY: Atrial fibrillation after cardiac surgery is still a frequent encountered complication and has been associated with increased hospital length of stay and numerous postoperative complications. The pathogenesis of atrial fibrillation involves an overall sequence of perioperative events, collectively termed as ischemia-reperfusion injury. Heat-shock proteins have been found to provide increased protection during ischemia-reperfusion as well as increased postischemic cardiac functional recovery. We sought to determine whether preoperative atrial heat shock levels were correlated with the appearance of postoperative atrial fibrillation. BASIC METHODS: Preoperative atrial myocardial samples obtained just before cannulation from 101 patients were used to detect immunohistochemically the expression of heat-shock proteins. The derived results were compared statistically with the incidence of postoperative atrial fibrillation, its time of appearance, duration and resistance to administered antiarrhythmics. PRINCIPAL FINDINGS: The overall incidence of postoperative atrial fibrillation was 22.3%. Of these patients, 58.3% had no detectable heat shock proteins in their cytoplasm, in sharp contrast with 100% of the patients with no atrial fibrillation who were positive for heat shock proteins (p<0.01). Four percent of our patient group had prolonged atrial fibrillation (defined as duration >48 h). These patients had significantly less (p<0.01) nuclear heat shock protein expression compared with the non-atrial fibrillation group. However, the difference of the heat shock protein expression between the prolonged atrial fibrillation and the rest of the atrial fibrillation patients was not significant (p=0.891). CONCLUSIONS: Our results indicate that patients with low preoperative atrial heat shock protein expression have a significantly greater incidence of postoperative atrial fibrillation. Heat shock protein expression did not, however, correlate with the onset of atrial fibrillation and the resistance to administered medications. Heat shock protein preoperative induction as a measure of myocardial preconditioning may potentially decrease the incidence of postoperative atrial fibrillation.  相似文献   
32.
Spinal cord ischemia is a major cause of complications after operative and endovascular treatment of descending thoracic or thoracoabdominal aortic aneurysms. Prior revascularization of the intercostal artery (IA) giving rise to the artery of Adamkiewicz (AA) using an artery of the thoracic wall would preserve circulation in the AA and allow obstruction of the IA at its origin. The purpose of this study was to determine the feasibility of revascularization of the IA giving rise to the AA using three thoracic wall arteries, i.e., lateral thoracic artery, thoracodorsal artery, and descending scapular artery. A total of 16 specimens from 8 cadavers (6 men and 2 women) were prepared. The length and diameter of the thoracic wall arteries were measured to ascertain the feasibility of revascularization of the IA giving rise to the AA. In addition, 12 preoperative spinal cord arteriograms were studied. We found that revascularization of the IA giving rise to the AA using thoracic wall arteries is feasible. This technique could be used to prevent spinal cord complications after treatment of descending thoracic or thoracoabdominal aortic aneurysms.  相似文献   
33.
This the case of a 63 year-old man with end-stage renal disease (on chronic hemodialysis), unstable angina and significantly impaired myocardial contractility with low left ventricular ejection fraction, who underwent off-pump one vessel coronary bypass surgery. Combined continuous levosimendan and norepinephrine infusion (at 0.07 μg/kg/min and 0.05 μg/kg/min respectively) started immediately after anesthesia induction and continued for 24 hours. The levosimendan/norepinephrine combination helped maintain an appropriate hemodynamic profile, thereby contributing to uneventful completion of surgery and postoperative hemodynamic stability. Although levosimendan is considered contraindicated in ESRD patients, this case report suggests that combined perioperative levosimendan/norepinephrine administration can be useful in carefully selected hemodialysis patients with impaired myocardial contractility and ongoing myocardial ischemia, who undergo off-pump myocardial revascularization surgery.  相似文献   
34.
Abstract Posttraumatic synostosis of the forearm bones is a rare but serious complication following fixation or even conservative treatment of adult forearm fractures. This is the second report in the English literature of such a complication at the pin-track site following external fixation of proximal forearm fractures. A 36-year-old male patient sustained an open fracture of his proximal right forearm after a road traffic accident. It was managed by external fixation of the ulna and plate fixation of the radius. At follow-up, a type 3 radio-ulnar synostosis at the pin-track site became evident, which was treated after 20 months with surgical resection of the bony bridge to regain the rotatory motion of his forearm. An erratum to this article is available at .  相似文献   
35.
Postoperative liver failure remains a major cause of morbidity and mortality after extensive hepatectomies. This study aims to evaluate the effectiveness of a hepatocyte bioreactor in the treatment of experimental post‐hepatectomy liver failure. Our experimental model included a combination of a side‐to‐side portacaval shunt, occlusion of the hepatoduodenal ligament for 150 min, 70% hepatectomy, and reperfusion. Following the development of liver failure, 12 pigs were randomized into a control group (n = 6) and a treatment group (n = 6). Both groups underwent extracorporeal perfusion through a plasma separation device, a membrane oxygenator, and two parallel bioreactors. In the latter group, the bioreactors were loaded with 10 billion fresh hepatocytes, isolated from a donor pig. Following hepatocyte treatment, all animals were maintained for 24 h under mechanical ventilation, with intravenous fluid and glucose supplementation. Hemodynamic parameters, intracranial pressure, and biochemical parameters were measured. Liver biopsies were obtained during the 24‐h autopsy. The extracorporeal circuit was well‐tolerated hemodynamically. Treated animals had lower intracranial pressure compared with controls (at 24 h, 15 ± 3.1 vs. 22 ± 3.5 mm Hg, P = 0.006). Plasma ammonia in treated animals was lower compared with controls at 12 h (100 ± 29 vs. 244 ± 131 µmol, P = 0.026). Liver histological study showed decreased necrosis and increased regeneration activity in treated animals compared with controls. Treatment through an extracorporeal hepatocyte bioreactor attenuates brain edema and improves histological and functional parameters of the liver remnant of pigs with posthepatectomy liver failure.  相似文献   
36.
Early diagnosis and active management of trans-anal rectal injuries is essential for a favorable outcome. Intraperitoneal free air (IFA) is usually diagnosed by an erect Chest X-ray. Point-of-care ultrasound has been recently used to detect IFA. We report a 45-year-old male who presented to the Emergency Department with lower abdominal peritonitis. Surgeon-performed portable point-of-care ultrasound as an extension of the abdominal examination revealed an inflamed omentum with hypoechoic stranding, thickened non compressible small bowel, and free fluid in the pelvis. A transverse abdominal section of the right upper quadrant showed free intraperitoneal air. Rectal examination revealed a longitudinal rectal tear. Laparotomy has confirmed the sonographic findings. There was a 12 cm intraperitoneal tear of the anterior wall of the rectum which was necrotic. This case clearly demonstrates that portable point-of-care ultrasound gives very useful detailed information even when performed by a non radiologist. Surgeons should be encouraged to use point-of-care ultrasound after appropriate training.  相似文献   
37.
Chatzizacharias NA, Vaidya A, Sinha S, Smith R, Jones G, Sharples E, Friend PJ. Renal function in type 1 diabetics one year after successful pancreas transplantation.
Clin Transplant 2011: 25: E509–E515. © 2011 John Wiley & Sons A/S. Abstract: The effect of pancreas transplantation on renal function remains a matter of debate. The purpose of this retrospective, single‐unit study is a preliminary analysis of renal function one yr after pancreas transplant (pancreas alone [PTA] or pancreas after kidney [PAK]). Fifty‐nine patients were included. Serum creatinine and estimated glomerular filtration rate (eGFR) levels were compared three, six, and 12 months post‐transplantation for the whole sample and separately for PTA and PAK and high (>45 mL/min/1.73 m2) and low (≤45 mL/min/1.73 m2) pre‐transplant eGFR subgroups. Overall, eGFR did not change significantly (p = 0.228) at the end of the first year post‐transplant, with patients of low initial eGFR presenting a more prominent trend toward stable or improved levels. In the PAK subgroup, eGFR was significantly improved (p = 0.035). High eGFR subgroup demonstrated no significant deterioration in renal function, while patients with low initial eGFR had significantly higher levels 3 (p = 0.012) and six months (p = 0.009) post‐transplant. Our study shows that renal function did not deteriorate significantly one yr after pancreas transplant (PTA or PAK), even in patients with substantial pre‐existing renal dysfunction. Evaluation at a wider scale and identification of risk factors for potential deterioration are challenges for future research.  相似文献   
38.
Use of various bisphosphonates has been associated with the development of osteonecrosis of the jaws (ONJ). At least 865 cases of ONJ attributed to these agents have been reported in the English-language literature. Approximately 96% of these published cases were seen with administration of the intravenous agents pamidronate and zoledronate, whereas only 26 cases have been associated with oral bisphosphonates, 25 of them with alendronate. Only a single case of ONJ associated with the oral bisphosphonate risedronate has been previously cited. We report 2 cases of ONJ attributed to risedronate administration. The patients developed osteonecrosis 15 and 24 months after treatment for osteopenia. A regimen of antibiotics and chlorhexidine mouthrinse resolved the osseous defect in the mandible caused by complete exfoliation of a lingual torus in 1 patient. The other patient required sequestrectomy, repeated courses of antibiotics, surgical debridement, and steroids to promote closure of an oroantral fistula and management of sinusitis after bone grafting and implant placement in the posterior maxilla. A demographic profile of reported oral bisphosphonate users affected by ONJ is also provided. With the millions of patients receiving various oral bisphosphonates for osteopenia and osteoporosis, health care practitioners should be aware of the potential for the onset of osteonecrosis and familiar with its management.  相似文献   
39.
40.
Background Experimental and clinical studies have demonstrated the pivotal role of oxidative stress in the promotion of hepatic and intestinal injury in obstructive jaundice. The present study was undertaken to investigate the effect of well known antioxidant treatments on the gut–liver axis oxidative status and function in bile duct-ligated rats. Methods A total of 60 male Wistar rats were randomly divided into six groups of 10 animals each: controls, sham operated, bile duct ligated (BDL), and BDL treated with either N-acetylcysteine (NAC), allopurinol, or α-tocopherol (α-TC). Ten days after treatment, the hepatic and intestinal oxidative status was estimated by measuring lipid peroxidation and a battery of biochemical markers comprising the organ’s thiol redox state (i.e., glutathione, cysteine, protein thiols, oxidized glutathione, nonprotein mixed disulfides, oxidized cysteine derivatives, protein symmetrical disulfides, and protein mixed disulfides). Portal and aortic endotoxin concentrations and alanine aminotransferase (ALT) levels were also determined. Results All antioxidant treatments significantly improved intestinal barrier function and protected from cholestatic liver injury, as evidenced by reduction of the portal and aortic endotoxin concentration and ALT levels, respectively. This effect accompanied their significant antioxidant action in both organs, mediated by a certain influence profile on the thiol redox state by each treatment. Conclusion NAC, allopurinol, and α-TC, exerting a potent combined antioxidant effect on the intestine and liver in experimental obstructive jaundice, significantly prevented intestinal barrier dysfunction and liver injury. The variety of results depending on the antioxidant agent that was administered and the marker of oxidative stress that was estimated, indicates that a battery of biomarkers would be more appropriate in assessing pharmacologic responses to therapeutic interventions.  相似文献   
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