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排序方式: 共有9744条查询结果,搜索用时 15 毫秒
81.
Enhanced Fluid Removal Guided by Blood Volume Monitoring During Chronic Hemodialysis 总被引:4,自引:0,他引:4
Robert R. Steuer Michael J. Germain John K. Leypoldt & Alfred K. Cheung 《Artificial organs》1998,22(8):627-632
Fluid overload predisposes chronic hemodialysis patients to cardiovascular disease, a significant cause of morbidity and mortality in these patients. We evaluated the efficacy of monitoring changes in blood volume during routine hemodialysis to detect fluid overload. Intradialytic changes in blood volume were monitored by continuously measuring hematocrit in all 56 patients in a single dialysis unit over 7 weeks. After Week 1, patients were categorized into 2 separate groups depending on their maximum intradialytic decreases in blood volume. In Group 1, 46 of 56 or 82% had greater than a 5% decrease in blood volume while in Group 2, 10 of 56 or 18% had less than a 5% decrease in blood volume. During Weeks 2–7, dialytic fluid removal was intentionally increased in Group 2 patients by 0.80 ± 0.62 L (mean ± SD) or 47 ± 43%. This intervention resulted in a larger (p < 0.02) intradialytic decrease in body weight (2.7 ± 0.9 kg versus 2.0 ± 0.8 kg) and a larger (p < 0.02) intradialytic decrease in blood volume (15 ± 5% versus 4 ± 1%) than experienced during Week 1 with a low incidence of symptoms. We conclude that there is a significant percentage of chronic hemodialysis patients who can tolerate additional fluid removal without hypovolemic symptoms even though they are considered to be at dry weight by routine physical examination and that the identification of these patients can be facilitated by intradialytic blood volume monitoring. 相似文献
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84.
Cervical nodal metastases from head and neck squamous cell carcinoma: MRI criteria for treatment assessment 下载免费PDF全文
85.
Objective: Two major changes have occurred in inguinal hernia repair during the last two decades: (i) the use of tension‐free mesh repair; and (ii) the application of laparoscopic technique for repair. The aims of the present study were to study: (i) how inguinal hernia repair was carried out; and (ii) the outcome of inguinal hernia repair in Hospital Authority (HA) hospitals. Methodology: This was a retrospective analysis on 8311 elective inguinal hernia repairs performed in 16 HA hospitals from January 2001 to December 2003. The mean age was 63.9 ± 14.2 years, and the male to female ratio was 22.0 : 1.0. Among these, 869 (10.5%) repairs were performed with the laparoscopic approach and 7442 (89.5%) repairs with the open approach. The proportion of laparoscopic hernia repair increased from 8.7% to 12.6%. Results: For open repair, 39% of cases were carried out with regional anaesthesia, 32% with general anaesthesia and 29% with local anaesthesia (LA). Furthermore, mesh repair was used in 88% of the patients. For laparosocpic repair, 98.4% of cases were carried out under general anaesthesia, and all patients had mesh repair using the totally extraperitoneal approach. A significantly higher proportion of bilateral repair and recurrent hernia repair was performed with the laparoscopic approach (P = 0.000). For primary unilateral repair, there was no significant difference in the postoperative length of stay (LOS) and the total LOS between the laparoscopic and the open surgery groups. No difference in LOS was found in recurrent hernia repair between the two groups. With respect to bilateral repair, both the preoperative LOS (P = 0.036) and total LOS (P = 0.039) were shorter in the laparoscopic group. Furthermore, a significantly higher proportion of day‐surgery patients was observed in the laparoscopic group than the open surgery group (21.3%vs 16.9%, P = 0.001). Nevertheless, when only the results of 2003 were analyzed, the postoperative LOS (P = 0.000) and total LOS (P = 0.000) were significantly shorter in the laparoscopic group than the open surgery group. The LOS parameters were significantly shorter in the open surgery LA subgroup compared with the non‐LA subgroup (P = 0.000), and they were not different from those in the laparoscopic group. Conclusions: The open mesh repair is the predominant approach for inguinal hernia repair in HA hospitals. The originally described local anaesthetic approach was under utilized, although it resulted in good outcome. The use of laparoscopic hernia repair is increasing and a learning curve was recently observed with improved outcome. 相似文献
86.
Liver resection for intrahepatic stones 总被引:10,自引:0,他引:10
HYPOTHESIS: Long-term outcome is good for a selected group of patients with hepatolithiasis treated with liver resection. Liver resection should also be offered to patients with complex hepatolithiasis such as bilateral stones or those with strictures. DESIGN: Retrospective study. SETTING: Regional hospital. PATIENTS: A total of 174 patients with hepatolithiasis (201 procedures) treated between January 1, 1989, and September 30, 2003. INTERVENTIONS: Liver resection (52 procedures) or removal of stones primarily by percutaneous choledochoscopy (149 procedures). MAIN OUTCOME MEASURE: Recurrence of cholangitis. RESULTS: Most patients in the liver resection group had stones localized to the left side. The overall success rate in this group was 98.0% (49 of 50 patients, excluding 2 patients found to have cholangiocarcinoma). The chance of biliary sepsis at 5 years after resection was 13.3%. The overall success rate of stone removal primarily by percutaneous choledochoscopy was 70.5%. The bilaterality of stones, the presence of stricture, and the presence of atrophy were found to be significant risk factors for a poor long-term outcome after stone removal alone. The chance of biliary sepsis at 5 years was 26.4% and 43.2% for those without and with stricture, respectively. CONCLUSIONS: The long-term outcome after liver resection for hepatolithiasis was excellent for a selected group of patients. Poor outcomes were recorded for patients whose intrahepatic stones were removed primarily by percutaneous choledochoscopy, especially those with strictures. The indication for liver resection for hepatolithiasis should be extended to patients with strictures and those with bilateral stones. A combination of different treatment modalities is necessary to improve the outcome of these patients. 相似文献
87.
Factors for conversion in laparoscopic cholecystectomy for acute cholecystitis: Is timing important?
Aim: Laparoscopic cholecystectomy is regarded as the gold standard treatment for gallstones. Conversion to open cholecystectomy is still common, and preoperative factors to predict conversion are useful in clinical practice. The aim of this study was to evaluate preoperative factors that could predict conversion in acute cholecystitis. Methods: This is a retrospective review of 83 patients with a diagnosis of acute cholecystitis who had laparoscopic cholecystectomy carried out as an emergency operation. Clinical, biochemical, and operative factors were analyzed for association with conversion. Results: A total of 83 patients were recruited to this study. The overall conversion rate was 33.7% (28/83). A longer duration of symptoms before presentation (P = 0.005) and surgery that was carried out over 48 h after admission (P = 0.022) were associated with a higher conversion rate. Emergency operations that began between 20.00 hours and 08.00 hours were also associated with a higher rate of conversion (P = 0.003). Other factors that were associated with conversion included male sex (P = 0.004), low albumin level upon admission (P = 0.024), prolonged prothrombin time (P = 0.040), and a raised serum total bilirubin level (P = 0.024). ASA scores were found to be similar in both groups (P = 0.509). Multivariate analysis by logistic regression showed that the independent risk factors for conversion in emergency laparoscopic cholecystectomy were surgery >48 h after admission (P = 0.028), emergency operation started between 20.00 hours and 08.00 hours (P = 0.026), and longer duration of symptoms before presentation (P = 0.034). Conclusions: Laparoscopic cholecystectomy should be carried out within 48 h of the patient being admitted for acute cholecystitis. The operation should be carried out during the daytime. 相似文献
88.
Maria G Vogiatzi Eric A Macklin Ellen B Fung Angela M Cheung Elliot Vichinsky Nancy Olivieri Melanie Kirby Janet L Kwiatkowski Melody Cunningham Ingrid A Holm Joseph Lane Robert Schneider Martin Fleisher Robert W Grady Charles C Peterson Patricia J Giardina 《Journal of bone and mineral research》2009,24(3):543-557
Adults with β thalassemia major frequently have low BMD, fractures, and bone pain. The purpose of this study was to determine the prevalence of low BMD, fractures, and bone pain in all thalassemia syndromes in childhood, adolescence, and adulthood, associations of BMD with fractures and bone pain, and etiology of bone disease in thalassemia. Patients of all thalassemia syndromes in the Thalassemia Clinical Research Network, ≥6 yr of age, with no preexisting medical condition affecting bone mass or requiring steroids, participated. We measured spine and femur BMD and whole body BMC by DXA and assessed vertebral abnormalities by morphometric X‐ray absorptiometry (MXA). Medical history by interview and review of medical records, physical examinations, and blood and urine collections were performed. Three hundred sixty‐one subjects, 49% male, with a mean age of 23.2 yr (range, 6.1–75 yr), were studied. Spine and femur BMD Z‐scores < ?2 occurred in 46% and 25% of participants, respectively. Greater age, lower weight, hypogonadism, and increased bone turnover were strong independent predictors of low bone mass regardless of thalassemia syndrome. Peak bone mass was suboptimal. Thirty‐six percent of patients had a history of fractures, and 34% reported bone pain. BMD was negatively associated with fractures but not with bone pain. Nine percent of participants had uniformly decreased height of several vertebrae by MXA, which was associated with the use of iron chelator deferoxamine before 6 yr of age. In patients with thalassemia, low BMD and fractures occur frequently and independently of the particular syndrome. Peak bone mass is suboptimal. Low BMD is associated with hypogonadism, increased bone turnover, and an increased risk for fractures. 相似文献
89.
Warren T. K. Lee Catherine S. K. Cheung Yee Kit Tse Xia Guo Ling Qin Suzanne C. Ho Joseph Lau Jack C. Y. Cheng 《Osteoporosis international》2005,16(9):1024-1035
Generalized low bone mass has been well documented in patients with adolescent idiopathic scoliosis (AIS). However, studies linking calcium-intake (CA), weight-bearing physical-activity (PA) and bone mass of AIS are lacking. We aimed to study the relationship between CA, PA and bone mass in AIS girls and compared to those of healthy non-AIS controls during the peripubertal period. Newly diagnosed AIS girls (n=596) aged 11–16 years with Cobb angle 10° were recruited to compare with age-matched healthy girls (n=302) in a cross-sectional study. Anthropometric parameters, pubertal status, CA and PA were assessed. Areal bone mass of lumbar spine and femoral neck, and volumetric bone mass of distal radius and tibia were determined by dual-energy X-ray absorptiometry and peripheral quantitative computed tomography, respectively. The results showed that weight and body mass index (BMI) of AIS were lower than the controls (P<0.05). Corrected height and arm span of AIS were longer than those of controls from 13 years onwards (P<0.02). Median CA of AIS was <410 mg/day across the ages and did not differ from the controls (P=0.063). Median PA of AIS (1.6 h/day) was lower than the controls (1.8 h/day) (P=0.025). Bone mass of AIS was on average 6.5% lower than controls across the ages (P<0.05). CA and PA were significantly correlated with bone mass of AIS (P<0.04). Multivariate analysis showed that AIS in girls was associated with lower bone mass, and that both CA and PA were independent predictors of bone mass in AIS. In conclusion, AIS girls were found to have lower body weight and BMI, longer segmental lengths and generalized low bone mass. Inadequate calcium intake and weight-bearing physical activity were significantly associated with low bone mass in AIS girls during the peripubertal period. The importance of preventing generalized osteopenia in the control of AIS progression during the peribubertal period warrants further study. 相似文献
90.
A preliminary study on electromyographic analysis of the paraspinal musculature in idiopathic scoliosis 总被引:4,自引:0,他引:4
John Cheung Jan P. K. Halbertsma Albert G. Veldhuizen Wim J. Sluiter Natasha M. Maurits Jan C. Cool Jim R. van Horn 《European spine journal》2005,14(2):130-137
The paraspinal muscles have been implicated as a major causative factor in the progression of idiopathic scoliosis. Therefore, the objectives of this preliminary study were to measure the electromyographic activity (EMG) of the paraspinal muscles to determine its relationship to progression of the scoliotic curve. Idiopathic scoliotic patients were selected and identified afterwards on curve progression. The EMG activity on both sides of the spine was measured in a set of standardized postures using bipolar surface electrodes at the apex and two end vertebrae of the scoliotic curve. An EMG ratio involving measurements of the EMG activity on the convex and concave sides of the scoliotic curve was used to evaluate the paraspinal muscles. Enhanced EMG ratios at the apex of the scoliotic curve were found in both groups during sitting and standing. The most interesting finding was that children with progression of the curve also showed enhanced EMG ratios at the lower end vertebra of the curve. The EMG ratios between the groups were significantly different from each other at the apex and end vertebrae for several test conditions. Overlap in the EMG-ratio ranges made differentiation difficult for prediction of the progression of the individual scoliosis patient. However, the EMG ratio at the lower end vertebra of the scoliotic curve is significantly higher than 1 in all test conditions in the group of children with subsequent progression of the curve, whereas it is always normal in the non-progressive group. Therefore, EMG of the paraspinal muscles might be of value for prediction of progression in idiopathic scoliosis. 相似文献