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131.
BACKGROUND: Ischemic preconditioning (IPC) has been found in animals to have a protective effect against future ischemic injury to muscle tissue. Such injury is unavoidable during some surgical procedures. To determine whether chronic ischemia in the lower extremities would imitate IPC and reduce ischemic injury during vascular surgery, we designed a controlled clinical study. PATIENTS AND METHODS: Two groups of patients at a university-affiliated medical centre with chronic lower-extremity ischemia served as models of IPC: 6 patients awaiting femoral distal bypass (FDB) and 4 scheduled for aortobifemoral (ABF) bypass grafting for aortoiliac occlusive disease. Seven patients undergoing elective open repair of an infrarenal abdominal aortic aneurysm (AAA) were chosen as non-IPC controls. Three hematologic indicators of skeletal-muscle injury, lactate dehydrogenase (LDH), creatine kinase (CK) and myoglobin, were measured before placement of the proximal clamp, during surgical ischemia, immediately upon reperfusion, 15 minutes after and 1 hour after reperfusion, and during the first, second and third postoperative days. RESULTS: Baseline markers of skeletal-muscle injury were similar in all groups. In postreperfusion samples, concentrations of muscle-injury markers were significantly lower in the 2 PC groups than in the control group. For example, at day 2, LDH levels were increased by about 30% over baseline measures in the elective AAA (control) group, whereas levels in the FDB and ABF groups remained statistically unchanged from baseline. Myoglobin in controls had increased by 977%, but only by 160% in the FDB and 528% in the ABF groups. CK levels, in a similar trend, were 1432% higher in the control group and only 111% (FDB) and 1029% (ABF) in the study groups. Taken together, these data represent a significant level of protection. CONCLUSIONS: Patients with chronic lower-extremity ischemia suffered less severe ischemic injury after a period of acute ischemia than those with acute ischemia alone. Ischemic preconditioning is one proposed mechanism to help explain this protective effect.  相似文献   
132.
Prevalence of malignancy within cytologically indeterminate thyroid nodules   总被引:2,自引:0,他引:2  
BACKGROUND: The optimal management of cytologically indeterminate thyroid nodules is controversial given the variable malignancy rates reported in this patient population. We examined the prevalence of malignancy within cytologically indeterminate follicular thyroid lesions in an attempt to predict malignancy based on cytologic features. METHODS: Cytopathology reports obtained after fine-needle aspiration biopsy (FNAB) examination of indeterminate follicular thyroid lesions were examined over a 4-year period. The prevalence of malignancy on final histology was determined in 4 indeterminate cytologic categories. RESULTS: A total of 107 records were available (91 women, 16 men). The mean patient age was 45.4 +/- 16 years. Forty-eight patients (45%) underwent surgery and had histopathologic diagnosis, while 57 patients did not have surgery. The prevalence of malignancy in patients who underwent thyroidectomy was 42% (20 of 48). CONCLUSIONS: The high prevalence of malignancy within indeterminate follicular lesions may necessitate thyroidectomy for patients with indeterminate follicular lesions on FNAB examination.  相似文献   
133.

Objective

The prevalence of skull fractures after mild head trauma is 2 % in children of all ages and 11 % in children younger than 2 years. The current standard management for a child diagnosed with an isolated skull fracture (ISF), in our institute, is hospitalization for a 24-h observation period. Based on data from the literature, less than 1 % of all minor head injuries require neurosurgical intervention. The main objective of this study was to evaluate the risk of neurological deterioration of ISF cases, in order to assess the need for hospitalization.

Methods

We reviewed the medical charts of 222 children who were hospitalized from 2006 to 2012 with ISF and Glascow Coma Scale—15 at the time of arrival. We collected data regarding demographic characteristics, mechanism of injury, fracture location, clinical symptoms and signs, need for hospitalization, and need for repeated imaging. Data was collected at three time points: at presentation to the emergency room, during hospitalization, and 1 month after admission, when the patients’ parents were asked about the course of the month following discharge.

Results

None of the 222 children included in the study needed neurosurgical intervention. All were asymptomatic 1 month after the injury. Two children underwent repeated head CT due to persistence or worsening of symptoms; these CT scans did not reveal any new findings and did not lead to any intervention whatsoever.

Conclusion

Children arriving at the emergency room with a minor head injury and isolated skull fracture on imaging studies may be considered for discharge after a short period of observation. Discharge should be considered in these cases provided the child has a reliable social environment and responsible caregivers who are able to return to the hospital if necessary. Hospital admission should be reserved for children with neurologic deficits, persistent symptoms, suspected child abuse, or when the parent is unreliable or is unable to return to the hospital if necessary. Reducing unnecessary hospitalizations can prevent emotional stress, in addition to saving costs for the child’s family and the health care system.
  相似文献   
134.
135.
136.
BackgroundAfter Roux-en-Y gastric bypass (RYGB), a substantial number of patients do not achieve successful long-term weight loss. In cases of loss of restriction, the application of an adjustable gastric band (“salvage banding”) over the gastric pouch, or gastrojejunostomy, could prevent weight regain or increase weight loss. The objective of this literature review is to provide an overview of the studies that report the effect of salvage banding after failed RYGB.MethodsA systemic literature search was conducted in PubMed, Google Scholar, Medline, the Cochrane Library, and the online websites of specific bariatric surgery journals to identify all relevant studies describing salvage banding after failed RYGB.ResultsSeven studies, with a total of 94 patients, were included for a systemic literature review. Inclusion criteria for salvage banding varied from unsuccessful weight loss to technical pouch failure. After salvage banding, all studies reported further weight loss, varying from 55.9%–94.2% excess body mass index loss (EBMIL) after 12–42 months of follow-up. In the included study group, 18% (17/94) of the patients developed long-term complications requiring a re-revision in 17% (16/94) of the cases.ConclusionThe results of all 9 studies that were included in this review report a further increase in weight loss after salvage banding for failed RYGB. In case of insufficient weight loss or technical pouch failure after RYGB, all reports suggest that salvage banding is a safe and feasible revisional procedure. Prospective studies are necessary to determine to the success of direct application of an adjustable gastric band in primary RYGB.  相似文献   
137.
Study Type – Therapy (multi‐centre retrospective cohort) Level of Evidence 2b What's known on the subject? and What does the study add? Upper urinary tract urothelial carcinomas (UUT‐UCs) are rare tumours. Because of the aggressive pattern of UC, radical nephroureterectomy (RNU) with bladder cuff removal remains the ‘gold‐standard’ treatment. However, conservative strategies, such as segmental ureterectomy (SU) or endourological management, have also been developed in patients with imperative indications. Some teams are now advocating the use of conservative management more commonly in cases of elective indications of UUT‐UCs. Due to the paucity of cases of UUT‐UC, only limited data are available on the oncological outcomes afforded by conservative management. We retrospectively investigated the oncological outcomes after SU and RNU in a large multi‐institutional database. Overall, 52 patients were treated with SU and 416 with RNU. There was no statistical difference between the RNU and SU groups for the 5‐year probability of cancer‐specific survival, recurrence‐free survival and metastasis‐free survival. The type of surgery was not a significant prognostic factor in univariate analysis. The results were the same in a subgroup analysis of only unifocal tumours of the distal ureter with a diameter of <2 cm and of low stage (≤T2). Our results suggest that oncological outcomes after conservative treatment with SU are comparable to RNU for the management of UUT‐UC in select cases.

OBJECTIVE

  • ? To compare recurrence‐free survival (RFS), metastasis‐free survival (MFS) and cancer‐specific survival (CSS) after segmental ureterectomy (SU) vs radical nephroureterectomy (RNU) for urothelial carcinoma (UC) of the upper urinary tract (UUT‐UC) located in the ureter.

PATIENTS AND METHODS

  • ? We performed a multi‐institutional retrospective review of patients with UUT‐UC who had undergone RNU or SU between 1995 and 2010.
  • ? Type of surgery, Tumour‐Node‐Metastasis status, tumour grade, lymphovascular invasion and positive surgical margin were tested as prognostic factors for survival.

RESULTS

  • ? In all, 52 patients were treated with SU and 416 with RNU. The median (range) follow‐up was 26 (10–48) months.
  • ? The 5‐year probability of CSS, RFS and MFS for SU and RNU were 87.9% and 86.3%, respectively (P= 0.99); 37% and 47.9%, respectively (P= 0.48); 81.9% and 85.4%, respectively (P= 0.51).
  • ? In univariable analysis, type of surgery (SU vs RNU) failed to affect CSS, RFS and MFS (P= 0.94, 0.42 and 0.53, respectively).
  • ? In multivariable analyses, pT stage and pN stage achieved independent predictor status for CSS (P= 0.005 and 0.007, respectively); the positive surgical margin and pT stage were independent prognostic factors of RFS and MFS (P= 0.001, 0.04, 0.009 and 0.001, respectively).
  • ? The main limitation of the study is its retrospective design, which is due to the rarity of the disease.

CONCLUSIONS

  • ? Short‐term oncological outcomes after conservative treatment with SU are comparable to RNU for the management of UUT‐UC in select cases and should be considered an option.
  • ? In every other case, RNU still represents the ‘gold standard’ for the treatment of UUT‐UC.
  相似文献   
138.

Purpose  

Bone defects resulting from tumour resection or curettage are most commonly reconstructed with autologous bone graft which is associated with limited availability and donor site morbidity. Recent research has focussed on synthetic biomaterials as bone graft substitutes. The aim of this study was to assess the safety and efficiency of a bone substitute as an alternative for autologous bone in the treatment of benign bone tumours and tumour-like lesions.  相似文献   
139.
Introduction: Clinicians often use the Van Nuys Prognostic Index (VNPI) to determine management of ductal carcinoma in situ (DCIS). The VNPI uses age, extent of DCIS, pathological grade and resection margins to stratify patients into three groups pertaining to risk of local recurrence: low-risk (where breast-conserving surgery - BCS - alone appears adequate), intermediate-risk (where BCS plus radiotherapy is recommended) and high-risk (where mastectomy may be the safest option). The purpose of this study was to determine patterns of management of DCIS in Australia and New Zealand according to the VNPI. Methods: Using the National Breast Cancer Audit for the period 2004-2009, 4578 cases of DCIS were identified where complete data were available. Patterns of management according to the VNPI were determined. The chi-squared test was used for statistical analysis. Results: In VNPI group 1, 77% of patients were treated with BCS compared with 63% in group 2 and 32% in group 3. Of patients in group 1 who underwent BCS, 58% also received adjuvant radiotherapy, compared with 80% in group 2. In group 3, 68% were treated with mastectomy, and of those who underwent BCS, 86% received radiotherapy. Overall, 23% of DCIS cases did not conform to best practice according to individual VNPI prognostic groupings. Conclusions: Significant differences in the management of DCIS according to VNPI groups were observed. The results suggest the possibility that some patients in the low-risk group were over-treated, while a proportion of patients in the intermediate- and high-risk groups were under-treated.  相似文献   
140.
Heniford BT  Park A  Ramshaw BJ  Voeller G 《Annals of surgery》2003,238(3):391-9; discussion 399-400
OBJECTIVE: To evaluate the efficacy and safety of laparoscopic repair of ventral hernias. SUMMARY BACKGROUND DATA: The recurrence rate after standard repair of ventral hernias may be as high as 12-52%, and the wide surgical dissection required often results in wound complications. Use of a laparoscopic approach may decrease rates of complications and recurrence after ventral hernia repair. METHODS: Data on all patients who underwent laparoscopic ventral hernia repair (LVHR) performed by 4 surgeons using a standardized procedure between November 1993 and October 2002 were collected prospectively (85% of patients) or retrospectively. RESULTS: LVHR was completed in 819 of the 850 patients (422 men; 428 women) in whom it was attempted. Thirty-four percent of completed LVHRs were for recurrent hernias. The patient mean body mass index was 32; the mean defect size was 118 cm2. Mesh, averaging 344 cm2, was used in all cases. Mean operating time was 120 min, mean estimated blood loss was 49 mL, and hospital stay averaged 2.3 days. There were 128 complications in 112 patients (13.2%). One patient died of a myocardial infarction. The most common complications were ileus (3%) and prolonged seroma (2.6%). During a mean follow-up time of 20.2 months (range, 1-94 months), the hernia recurrence rate was 4.7%. Recurrence was associated with large defects, obesity, previous open repairs, and perioperative complications. CONCLUSION: In this large series, LVHR had a low rate of conversion to open surgery, a short hospital stay, a moderate complication rate, and a low risk of recurrence.  相似文献   
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