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This study compares four different activated clotting time (ACT) point-of-care (POC) testing systems used at our institution for the management of patients undergoing heparin therapy. We evaluated these systems under identical conditions to determine their accuracy, reproducibility, ease of use, and cost. Two separate testing stations containing four ACT systems were used. The testing order was randomized for every sample and performed by two trained individuals. Samples of fresh heparinized whole blood were taken at regular intervals and distributed to each station. Each operator tested 50 samples, totaling 400 ACT tests. The ACT value was significantly affected by the type of machine used at both stations 1 and 2 (p < .001). Compared with all systems, the Medtronic ACT Plus Automated Coagulation Timer System (ACT Plus) resulted in the most consistent ACT values (median = 171, Interquartile Range (IQR): 169-175) and least variability (172.17 +/- 5.24). The Hemochron Signature Elite Whole Blood Microcoagulation System had the most variability (221.10 +/- 14.78) and yielded consistently higher ACT values (median = 220, IQR: 210-229.5) compared with other systems. The ACT values reported by the i-STAT Handheld and Test Cartridge Blood Analysis System (153.30 +/- 7.87) were consistently lower (median = 154, IQR: 147-161) in comparison to the ACT Plus and Medtronic HMS Plus Hemostasis Management System (180.60 +/- 7.60, median = 181, IQR: 175-186). There was no statistical difference in results between the two testing sites (p > .05) or the operators (p > .05). The significant finding of this study was the affect each system has on the ACT value. This investigation demonstrates the variability that exists among different ACT monitoring systems at our institution. The discrepant variation in ACT values that exists with the Hemochron system questions the reliability of its use in the management of patients undergoing heparin therapy.  相似文献   
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Diabetic patients with end-stage renal disease have a high mortality rate. A combined kidney-pancreas transplant is associated with greater life expectancy. Pancreas islet transplantation is an alternative involving a lower degree of morbidity. We present two patients, of 41 and 37 years of age, with a long history of diabetes mellitus (C-peptide negative), both with a previous kidney transplant, who had been treated with 22 and 28 U of insulin/d, respectively. Both patients had frequent episodes of unawareness hypoglycemia. Pancreatic islets were infused to a total of 7809 and 19,180 IE/kg, respectively. Basal posttransplant C peptide levels were 2.9 and 1.3 ng/mL. After the implant, one patient required occasional doses of insulin, and the other patient more than 50% reduced dose. After the first implant neither patient had any episodes of unawareness hypoglycemia. HbA1c at 4 months were 6.2% and 6.9%. There were no transplant-related complications.  相似文献   
15.
Surgical treatment is the procedure of choice for morbidly obese patients. Gastric bypass with a long limb Roux-en-Y anastomosis is the "gold standard" technique for these patients. We sought to determine the early and late results of open gastric bypass with resection of the distal excluded stomach in patients with morbid obesity. We included in this prospective study 400 patients who were seen from September 1999 through August 2003 (311 women and 89 men; mean age, 38.5 years). The mean body mass index of the patients was 46 kg/m2. All underwent 95% distal gastrectomy, with resection of the bypassed stomach, leaving a small gastric pouch of 15 to 20 ml. An end-to-side gastrojejunostomy was performed with circular stapler No. 25. The length of the Roux-en-Y loop was 125 to 150 cm. In all patients, a biopsy was taken from the liver and routine cholecystectomy was performed. Follow-up was as long as 36 months. A barium study was performed in all patients at 5 days after surgery. Mortality and postoperative morbidity rates were 0.5% and 4.75%, respectively, mainly due to anastomotic leak in 10 patients (2.5%). Hospital length of stay was 7 days for 95% of the patients. Follow-up data for longer than 12 months were available in 184 patients. There was excess body weight loss of 70% at 24 and 36 months, and there was an inverse correlation among preoperative body mass index and the loss of weight. Anemia was present in 10%, and incisional hernia was present in 10.2%. At 1 year after surgery, the BAROS index demonstrated very good or excellent index in 96.6% of the patients. Gastric bypass with resection of the distal excluded segment has results very similar to those of gastric bypass alone but eliminates the potential risks of gastric bypass such as anastomotic ulcer, gastrogastric fistula, postoperative bleeding due to peptic ulcer and gastritis, and the eventual future development of gastric cancer. It is also possible to perform via laparoscopy, as we started to do recently.  相似文献   
16.
The aim of the present study was to investigate the utility in renal transplant patients of the guidelines for the diagnosis and classification of chronic kidney disease (CKD) based on the estimated glomerular filtration rate (GFR) elaborated by the Kidney Disease Outcomes Quality Initiative (K/DOQI) of the National Kidney Foundation. PATIENTS AND METHODS: Four hundred forty-seven cadaveric kidney transplants performed between 1980 and 1994 with graft function at 12 months were included in the study. The GFR was calculated according to the MDRD equation. RESULTS: The mean GFR at 12 months was 54.5 +/- 20.3 mL/min/1.73 m(2): 23 patients (5.1%) had a GFR > or =90 mL/min/1.73 m(2); 136 patients (30.6%), 60-89; 246 (54.7%), 30-59; 35 patients (7.8%), 15-29; and 7 patients (1.6%), GFR <15. Similar distribution of CKD stages was observed at 5 and 10 years. Unadjusted graft survival at 10 years was better among patients with a higher GFR at 12 months: 87% in patients with GFR >90 mL/min/1.73 m(2); 83% of GFR 60-89 mL/min/1.73 m(2); 63%, GFR 30-59 mL/min/1.73 m(2); and 23%, GFR <30 mL/min/1.73 m(2) (P < .001). The association between GFR and graft survival persisted when adjusted by the age and gender of the recipients and donors, time on dialysis, body mass index, immunosuppression, delayed graft function, rejection, and HLA mismatches. The prevalence of complications, such as anemia, hypertension, dyslipidemias, and number of drugs increased as GFR declined. CONCLUSIONS: More than 60% of recipients presented chronic kidney disease. GFR was a predictive factor for graft survival at 10 years. The classification of renal transplant patients by CKD stages may help to identify patients with increased risk of graft loss and also to design strategies to improve outcomes.  相似文献   
17.
We have reviewed our experience in selective cytomegalovirus (CMV) infection prophylaxis and treatment in our renal transplant population. Between 1996 and 2001, 263 cadaveric renal transplant recipients had at least 6 months follow up. Immunosuppression was based on cyclosporine Neoral (n=108) or tacrolimus (n=155). CMV infection prophylaxis (oral acyclovir or gancyclovir at half usual doses) was only prescribed in recipients receiving a CMV positive ve kidney and in recipients treated with OKT3. CMV infection was diagnosed by a positive pp65 antigenemia upon appearance of CMV-related symptoms, leading to specific treatment (IV ganciclovir) only if symptoms were intense or there was visceral involvement. Thus, no preemptive treatment or programmed or periodic antigenemia was performed in any case. Nineteen episodes of symptomatic CMV infection were diagnosed (prevalence 7.2%). The frequency was similar for all immunosuppressive regimens. Only 9 of 19 (47%) of patients were given IV ganciclovir; the others were not treated. All patients survived without apparent complications, relapses, or recurrences. No oral gancyclovir was delivered after IV treatment. Our CMV prophylaxis protocol was limited to high-risk patients, using lower gancyclovir dosages than those usually advocated. It does not include programmed or scheduled search for CMV antigenemia in asymptomatic renal transplant patients. Despite these factors, our CMV infection rate and severity were similar to those reported with more aggressive protocols, with extended prophylaxis, preemptive therapy, or intense surveillance.  相似文献   
18.
Because of the extraperitoneal location, generally used for renal grafting, intraperitoneal urine leaks are a rare complication after transplantation. We report a patient on peritoneal dialysis who developed ascites, abdominal pain, anuria and shock suddenly after renal transplantation. The patient was immediately taken back to the operating room. An abnormal implantation of ureter into the peritoneum overlying the bladder when carrying out an unstented parallel incision extravesical ureterone-ocystostomy was identified. After correcting ureter implantation the patient had immediate diuresis, renal function rapidly improved, with no further complications. Contributing causes were poor exposure, thickened peritoneum secondary to recurrent peritonitis, and the presence of residual peritoneal dialysis fluid.  相似文献   
19.
INTRODUCTION : In patients with common bile duct (CBD) stones, the diameter of the CBD is usually dilated. After surgery, the behavior of CBD diameter is not clearly known. OBJECTIVE : To determine at a late follow-up the width of CBD before and after choledochostomy for CBD stones. MATERIAL AND METHODS : In this prospective study, 39 patients with gallstones and CBD stones were included. They were 30 women and 9 men with a mean age of 52.6 years. In all ultrasound, determination of the CBD caliber before and 12 years after surgery was performed. RESULTS : The mean value of the inner diameter of the CBD before surgery was 11.6 and 12.3 mm in patients below or above 60 years, respectively. Measurement 12 years after surgery showed a mean decrease of nearly 50% of preoperative values, which was highly significant (p < 0.0001). However, either below or above 60 years, only 75% of the patients showed this decrease, whereas 25% remained unchanged. CONCLUSION : The dilated preoperative CBD returns to normal or near normal values in 3/4 of the patients after surgical exploration of the CBD and extraction of the stones.  相似文献   
20.

Background

In Spain, the number of ideal kidney transplant donors has fallen, with at the same time an increase in the number of older recipients on the waiting list.

Aim

To analyze the results of expanded criteria cadaveric donor kidney transplants into older recipients using grafts selected by kidney biopsy.

Patients and methods

We studied 360 kidney transplant recipients who had been followed to December 2009: 180 in the study group and 180 in a control group composed of younger patients who received grafts from non-expanded criteria donors between 1999 and 2006. A paraffin-embedded kidney biopsy was evaluated by the percentages of sclerosed glomeruli, arteriolar hyalinosis, intimal wall thickening, interstitial fibrosis, and tubular atrophy.

Results

Significant differences were observed in donor age (63.50 ± 5.46 vs 31.90 ± 13.29 years; P < .001) and recipient age (58.40 ± 8.80 vs 40.71 ± 13.23 years; P < .001). Donor renal function was significantly worse among the expanded criteria group (90.80 vs 108.11 mL/min/1.73 m2; P = .006), remaining so over time in the recipient (at 1 year: 42.08 vs 63.71 [P < .001]; at 3 years: 41.25 vs 62.31 [P < .001], and at 7 years: 38.17 vs 64.18 [P < .001]). Censored 7-year graft survivals were 73% versus 87% (P < .001) with similar patient survivals (90.5% vs 95%; P = .39).

Conclusions

Selection of expanded criteria donors by kidney biopsy resulted in good renal function as well as graft and patient survivals at 7 years in older recipients.  相似文献   
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