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61.
Data exist on the morbidity and mortality of patients undergoing pancreaticoduodenectomy (PD), but there are few reports about hospital readmissions after this procedure. Our aim was to evaluate the number of and reasons for readmission after PD and the factors influencing readmission. We reviewed the initial hospitalization and readmissions for 1643 patients undergoing PD compared patients requiring readmission to patients that did not require readmission. Twenty-six percent of patients were readmitted a total of 678 times after PD. Patients readmitted were younger than those not readmitted (61.8 versus 64.6 years, P<0.0001). Vessel resection, abscess formation, wound infection, postoperative percutaneous biliary stents, estimated blood loss >1000 ml, and age ⩽65 years were independently associated with readmission. The length of stay for all patients decreased over time, from 10.5 days in 1996 to 7 days in 2003. The percentage of patients being readmitted also decreased from 33% in 1996 to 20% (P=0.004) in 2003. The readmission rate after PD was 26%. Younger age, blood loss, postoperative complications, and vessel resection were independent risk factors for readmission. The early hospital readmission rate has not increased in association with a decreased LOS, supporting the idea that reduction in LOS did not lead to increased readmission rates. Presented at the Forty-Seventh Annual Meeting of The Society for Surgery of the Alimentary Tract, Los Angeles, California, May 22, 2006.  相似文献   
62.
Modular tibial components are the clinical standard in total knee arthroplasty despite the lack of evidence of improved function and longevity when compared with monoblock implants. This study describes the minimum 5-year outcomes for 125 total knee arthroplasties performed with monoblock tibial components in 101 patients. No patients were lost to follow-up. Average Knee Society Score was 87.1 at a mean follow-up of 5.2 years. Clinical and radiographic follow-up showed all components to be stable, no implants at risk of loosening, no observable osteolysis, and no observed change in bone density. Survivorship free of revision for tibial component loosening was 100% at 5 years. These results show excellent midterm durability of a partially cemented porous tantalum monoblock implant with uncemented pegs.  相似文献   
63.
STUDY DESIGN: Retrospective study of patients after extension of previous scoliosis fusions to the pelvis. OBJECTIVE: To determine whether modern instrumentation and surgical techniques provide for increased fusion rates with fewer complications. SUMMARY OF BACKGROUND DATA: Traditionally, long fusions to the pelvis in adults with idiopathic scoliosis have resulted in high complication rates, including pseudarthrosis. METHODS: The hospital and clinic charts of 41 patients (40 female, 1 male) were reviewed 41 months (range: 24-116) after surgery for extension to the pelvis of previous scoliosis fusions. Thirty-nine of 41 had a combined anteroposterior fusion extension; two had posterior extension only. In 37 of 41 patients, Cotrel-Dubousset (CD) instrumentation was used; in two, Isola (Acromed Corp., Cleveland, OH), in one, TSRH; (Sofamor-Danek, Memphis, TN), and in one, Synergy (Cross Medical Products, Columbus, OH). Parameters analyzed were fusion rate, sagittal and coronal balance, lumbar lordosis, length of fusion extension, and distal fixation method. RESULTS: Complications were seen in 30 of 41 patients. The pseudarthrosis rate was 37% (15/41) and was significantly related to the method of distal posterior fixation. With sacral fixation only, the rate was 53% (8/15), with iliac fixation only 42% (3/7), and with both iliac and sacral fixation 21% (4/19; P < 0.05). This was not correlated with fusion rate, and the length of fusion extension did not affect the pseudarthrosis rate or sagittal balance. CONCLUSION: When fixed to the ilium and sacrum, modern instrumentation appears capable of maintaining sagittal balance with lower rates of pseudarthrosis when previous scoliosis fusions are extended to the pelvis. The complication rate remains significant.  相似文献   
64.
OBJECTIVES: duplex ultrasound has replaced angiography prior to carotid endarterectomy (CEA) in many institutions. However, the indications for CEA are based on angiographically controlled studies and widely accepted ultrasound criteria do not exist. Consequently, the reliability of Doppler and/or duplex ultrasound to predict a high-grade ICA stenosis has to be proven. DESIGN: prospective validation study. MATERIALS: one hundred and fifty carotid bifurcations assessed by ultrasound and selective angiography and 68 acrylat outcasts of carotid specimen after eversion CEA. METHODS: ICA stenosis was measured angiographically according to the ECST criteria. Combined Doppler acoustic standard criteria (CDASC), peak systolic frequency (PSF), peak systolic velocity (PSV) and end-diastolic velocity (EDV) served as criteria for the ultrasound assessment. These criteria and the results of angiography were compared to the degree of ICA stenosis determined by specimen measurements. RESULTS: the median degree of ICA stenosis as assessed by angiography (82%, range 56-97%) and CDASC (83%, range 50-99%) corresponded well to the specimen measurements (80%, range 50-95%). The sensitivity of angiography and CDASC to predict a 70-90% ICA stenosis (ECST criteria) compared to the specimen measurements was 88% and 95%, respectively. The positive predictive value (PPV) reached 92% and 96%, respectively. CDASC were equivalent to angiography and were superior to the best single frequency or velocity parameters. If CDASC do not indicate a >/=70% ICA stenosis in spite of a PSV >/=180 cm/s and/or an EDV >/=50 cm/s, angiography may detect patients with a >70% ICA stenosis. CONCLUSIONS: CDASC are valid in the quantification of high-grade ICA stenosis. They are more reliable than single velocity and/or frequency measurements. However, if velocity criteria and CDASC do not agree, angiography should be performed.  相似文献   
65.
BACKGROUND: The routine use of nasogastric tubes in patients undergoing elective abdominal operation is associated with an increased incidence of postoperative fever, atelectasis, and pneumonia. Previous studies have shown that nasogastric tubes have no significant effect on the incidence of gastroesophageal reflux or on lower esophageal sphincter pressure in healthy volunteers. We hypothesized that nasogastric intubation in patients undergoing laparotomy reduces lower esophageal sphincter pressure and promotes gastroesophageal reflux in the perioperative period. METHODS: A prospective randomized case-control study was undertaken in which 15 consenting patients, admitted electively for bowel surgery, were randomized into 2 groups. Group 1 underwent nasogastric intubation after induction of anesthesia, and Group 2 did not. All patients had manometry and pH probes placed with the aid of endoscopic vision at the lower esophageal sphincter and distal esophagus, respectively. Nasogastric tubes, where present, were left on free drainage, and sphincter pressures and pH were recorded continuously during a 24-hour period. Data were analyzed with 1-way analysis of variance. RESULTS: The mean number of reflux episodes (defined as pH < 4) in the nasogastric tube group was 137 compared with a median of 8 episodes in the group managed without nasogastric tubes (P =.006). The median duration of the longest episode of reflux was 132 minutes in Group 1 and 1 minute in Group 2 (P =.001). A mean of 13.3 episodes of reflux lasted longer than 5 minutes in Group 1, with pH less than 4 for 37.4% of the 24 hours. This was in contrast to Group 2 where a mean of 0.13 episodes lasted longer than 5 minutes (P =.001) and pH less than 4 for 0.2% of total time (P =.001). The mean lower esophageal sphincter pressures were lower in Group 1. CONCLUSIONS. These findings demonstrate that patients undergoing elective laparotomy with routine nasogastric tube placement have significant gastroesophageal reflux in the perioperative period and a reduced ability to clear refluxed acid from the distal esophagus. Due to the associated risk of postoperative pulmonary complications, we recommend that nasogastric intubation be performed on a selective rather than routine basis.  相似文献   
66.
67.
Alveolar bone quality is considered to be an important prognostic factor in dental implant stability. Although numerous methods have been described, no technique allows for reliable diagnostics. The purpose of this study was to determine if strain measurements on the shaft of a contra angle handpiece during implant bed preparation could be used for the determination of bone quality. Experiments in polyurethane foam and human cadaver bone were conducted to investigate whether strain measurements could be correlated with other diagnostic parameters, such as the surgeon's tactile sensation during drilling, implant insertion torque, implant stability, elastic modulus of bone and bone quality as assessed radiographically. Tests were also performed to determine if strain measurements could be used to distinguish various types of bone. As axial feed and contact pressure during the drilling process could not be standardized under simulated clinical conditions, substantial deviations in the time needed to complete the drilling occurred. Under controlled circumstances using polyurethane foam, this problem could be addressed by a normalization procedure, but great variations occurred in human cadaver bone. As bone quality could not be reliably determined, especially when a cortical layer was present, strain measurements on a contra angle handpiece appears to be inappropriate for this purpose.  相似文献   
68.
Thirteen patients with progressive congenital scoliosis due to hemivertebrae or hemivertebrae associated with other spinal anomalies were treated by convex anterior and posterior hemiarthrodesis and hemiepiphysiodesis. The average curve prior to operation was 46 degrees, average age was 3 years 6 months, and average followup was 6 years 6 months. One patient failed because of an inadequate length of anterior surgery which was successfully salvaged by further surgery. Twelve patients were successes: Seven had only cessation of the progressive curve, and five had progressive curve improvement greater than or equal to 5 degrees due to the arrested convex and persistent concave growth. This procedure is a valuable treatment modality for selected patients with congenital scoliosis.  相似文献   
69.
70.
Sixty-six source contacts of index patients with first-episode genital infection caused by herpes simplex virus (HSV) were evaluated for evidence of current or past HSV infections. Forty-three source contacts (65%) reported a history consistent with previous recurrent HSV infection or were experiencing a first episode of genital herpes when initially examined. However, 60% of these 43 contacts were not aware that they had transmissible HSV infection. Twenty-nine (67%) of the 43 individuals had had recent sexual contact with an index patient when lesions were present. All of the remaining 23 source contacts, who were without a history of symptoms consistent with HSV infection, had detectable neutralizing antibody to HSV; HSV type 2 was isolated from the cervix of two of these asymptomatic source contacts. Efforts to identify individuals with undiagnosed genital herpes and to instruct these individuals concerning the risk of disease transmission in the presence of lesions are needed if the rate of transmission is to be decreased; however, methods designed to decrease the rate of transmission by asymptomatic individuals must also be evaluated.  相似文献   
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