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101.
The mechanisms by which aging induces muscle impairment are not well understood yet. We studied the impact of aging on Ca2+ homeostasis in the slow-twitch soleus and the fast-twitch extensor digitorum longus (EDL) muscles of aged rats by using the fura-2 fluorescent probe. In both muscles aging increases the resting cytosolic calcium concentration ([Ca2+]i). This effect was independent on calcium influx since a reduced resting permeability of sarcolemma to divalent cations was observed in aged muscles likely due to a reduced activity of leak channels. Importantly the effects of aging on resting [Ca2+]i, fiber diameter, mechanical threshold and sarcolemmal resting conductances were less pronounced in the soleus muscle, suggesting that muscle impairment may be less dependent on [Ca2+]i in the slow-twitch muscle. The treatment of aged rats with growth hormone restored the resting [Ca2+]i toward adult values in both muscles. Thus, an increase of resting [Ca2+]i may contribute to muscle weakness associated with aging and may be considered for developing new therapeutic strategies in the elderly.  相似文献   
102.
A tension pneumothorax is a known life-threatening condition which requires a needle decompression. A diaphragmatic rupture is a relatively rare injury and is difficult to diagnose. A combination of a tension pneumothorax in presence of an ipsilateral diaphragmatic rupture can be called life-saving since the air in the pleural space is able to escape to the abdomen. The diagnosis of a diaphragmatic rupture by computed tomography or even by laparo- or thorascopy is crucial. Surgical repair should always be undertaken because the rupture will not close spontaneously and the risk of herniation of intra-abdominal organs to the pleural space will remain. In presence of a chest tube on suction, iatrogenic migration or even perforation of these organs can occur.  相似文献   
103.
Objective: Data regarding risks and consequences of acute kidney injury (AKI) after cardiac transplantation are dismissingly few and unclear. This study defined the incidence, risk factors and prognostic implication of AKI in a single-center cohort operated on between January 1999 and December 2008. Methods: Data from 307 consecutive recipients (mean age: 47.42 ± 13.58, 20.5% female, 18.9% diabetics, 19.5% with previous cardiac operations, 26.4% hospitalized, 78.4 ± 33.7 ml min−1 preoperative glomerular filtration rate (eGFR)) were analyzed using multivariable logistic regression modeling. AKI was defined according to RIFLE (Risk, Injury, and Failure; and Loss, and End-stage kidney disease) criteria. Results: RIFLE scores of I or F were detected in 14%, and continuous venovenous hemofiltration was needed in 6.1%. Risk factors for AKI were: previous cardiac operation (odds ratio (OR) 2.35; 95% confidence interval (CI), 1.11–4.9), blood transfusion (OR 1.08; 95% CI, 1.011–1.16), troponin I release >10 (OR 1.031; 95% CI, 1.001–1.064), length of ischemic time (OR 1.008; 95% CI, 1.011–1.16). Overall hospital mortality averaged 7.8% and overall 1-year mortality was 10.4%; both mortality rates increased with each RIFLE stratification (Normal 3.4%, RIFLE R = 7.1%; RIFLE I = 25.7%; and RIFLE F = 37.5% and Normal 5.6%, RIFLE R = 11.8%, RIFLE I = 25.7%, and RIFLE F = 37.5%, respectively). AKI proved independent predictors of both early and 1-year mortality. The burden of AKI significantly affected 1-year kidney function (Δ preoperative GFR − 1-year GFR in AKI vs no AKI = −25.872 ± 22.54 vs −7.968 ± 34.18, p = 0.015). Conclusions: AKI is a highly prevalent and prognostically important complication. Some of the risk factors for AKI identified may be modifiable.  相似文献   
104.

Objective:

To evaluate the short-term outcomes of laparoscopic colorectal surgery for cancer in the elderly compared with younger patients.

Methods:

We retrospectively considered a consecutive unselected series of 159 patients who underwent elective laparoscopic procedures for colorectal cancer at our institution between January 2007 and December 2009. Of these patients, 101 (63.5%) were ≤70 years of age (Group A), and 58 (36.5%) were >70 (Group B). Operative steps and instrumentation were standardized. Demographics, disease-related, operative, and short-term data were analyzed for each group, and an appropriate statistical comparison was made. Comorbidity was quantified by using the Charlson Comorbidity Index.

Results:

We reviewed right colectomies (29.5%), left colectomies (44.7%), rectal resections (19.5%), and other procedures (6.3%). There was no significant difference in sex ratio, body mass index, American Society of Anesthesiology score, type of surgical procedures, and tumor stage between Group A and Group B. A statistically higher comorbidity according to the Charlson index characterized Group B (2.2 vs 3.8; P=.034). Median operative time (228±78.1min vs 224.3±97.6min; NS), estimated blood loss (50.0±94.8mL vs 31.2±72.7mL; NS), conversion rate (2.0% vs 1.7%; NS), and timing to canalization (4.5±1.7dd vs 4.4±1.3dd; NS) were statistically comparable in both Groups. Group B was associated with a significantly longer length of hospital stay compared with Group A (8.1±2.8dd vs 10.8±6.6dd; P<.01) There was no statistically significant difference in major postoperative complications (3.8% vs 3.4%; NS), reoperations (0.9% vs 1.7%; NS), and 30-day mortality (0% vs 1.7%; NS).

Conclusions:

Laparoscopic colorectal surgery appears feasible and safe in elderly patients with increased comorbidity.  相似文献   
105.
106.
Bile leak after hepatectomy: predictive factors of spontaneous healing   总被引:1,自引:0,他引:1  
BACKGROUND: Bile leakage after hepatectomy usually has spontaneous healing, but some patients require interventional procedures. To identify early predictive factors of conservative management failure. METHODS: This study focused on patients with bile leak after hepatectomy without extrahepatic biliary resection from 1996 through 2006. RESULTS: Bile leakage occurred in 34 of 593 patients (5.7%). Conservative management was successful in 26 patients (76.5%). At univariate analysis overall associated resections, vascular associated resections, and drainage output on days 1, 3, and 10 from leak onset were significant negative predictors of spontaneous healing. At multivariate analysis drainage output greater than 100 mL on day 10 was the only independent prognostic factor of conservative management failure (relative risk, 55.985; P = .008) with 80% sensitivity, 93.3% specificity, and 90% accuracy. CONCLUSIONS: Wait-and-see treatment is successful in most cases. Patients with drainage output greater than 100 mL 10 days after bile leakage diagnosis should be scheduled for interventional treatments.  相似文献   
107.
Background Although the feasibility of laparoscopic resection of gastric gastrointestinal stromal tumors (GISTs) has been established, various aspects are debated. This paper describes the problems of minimally invasive resection of gastric GISTs and compares this experience with an extensive literature review. Study Design Between August 2001 and December 2006, 21 consecutive patients undergoing laparoscopic resection of gastric GISTs were enrolled in a prospective study. A literature review of laparoscopic treatment was performed on Pubmed using keywords GIST and surgery. A comparison with authors’ experience with open wedge-segmental resection of GISTs (25 cases from November 1995 to December 2000) was also carried out. Statistical analysis was based on chi-squared test and t Student evaluation. Results Twenty-one patients, mean age 50.1 years (range, 34–68 years), were submitted to laparoscopic wedge- segmental gastric resections. Mean tumor size was 4.5 cm (range, 2.0–8.5 cm). Mean operative time was 151 min (range, 52–310 min), the mean blood loss was 101 mL (range, 10–250 mL), and the mean hospital stay was 4.8 days (range 3–7 days). There were no major operative complications or mortalities. All lesions had negative resection margins. At a mean follow-up of 35 months, all patients were disease-free. Morbidity, mortality, length of stay, and oncologic outcomes were comparable to the open surgery retrospective evaluation (p = not significant). Conclusions As found also in the literature review, the laparoscopic resection is safe and effective in treating gastric GISTs. Given these findings as well as the advantages afforded by laparoscopic surgery, a minimally invasive approach should be the preferred surgical treatment in patients with small- and medium-sized gastric GISTs.  相似文献   
108.
Background Left lateral sectionectomy is one of the most commonly performed laparoscopic liver resections, but limited clinical data are actually available to support the advantage of laparoscopic versus open-liver surgery. The present study compared the short-term outcomes of laparoscopic versus open surgery in a case-matched analysis. Materials and Methods Surgical outcome of 20 patients who underwent left lateral sectionectomy by laparoscopic approach (LHR group) from September 2005 to January 2007 were compared in a case-control analysis with those of 20 patients who underwent open left lateral sectionectomy (OHR group). Both groups were similar for: tumor size, preoperative laboratory data, presence of cirrhosis, and histology of the lesion. Surgical procedures were performed in both groups combining the ultrasonic dissector and the ultrasonic coagulating cutter without portal clamping. Results Compared with OHR, the LHR group had a decreased blood loss (165 mL versus 214 mL, P = 0.001), and earlier postoperative recovery (4.5 versus 5.8 days, P = 0.003). There were no significant differences in terms of surgical margin and operative time. Morbidity was comparable between the two groups, but two cases of postoperative ascites were recorded in two cirrhotic patients in the OHR. Major complications were not observed in either groups. Conclusions Laparoscopic resection results in reduced operative blood loss and earlier recovery with oncologic clearance and operative time comparable with open surgery. Laparoscopic liver surgery may be considered the approach of choice for tumors located in the left hepatic lobe.  相似文献   
109.
BACKGROUND: The impact of short-term preoperative pulmonary rehabilitation on exercise capacity of patients with chronic obstructive pulmonary disease undergoing lobectomy for non-small cell lung cancer is evaluated. METHODS: A prospective observational study was designed. Inclusion criteria consisted of an indication to lung resection because of a clinical stage I or II non-small cell lung cancer and a chronic obstructive disease on preoperative pulmonary function test. In such conditions, maximal oxygen consumption by a cardio-pulmonary exercise test was evaluated; when this resulted as being < or =15 ml/kg/min a pulmonary rehabilitation programme lasting 4 weeks was considered. Twelve patients fulfilled inclusion criteria, completed the preoperative rehabilitation programme and underwent a new functional evaluation prior to surgery. The postoperative record of these patients was collected. RESULTS: On completion of pulmonary rehabilitation, the resting pulmonary function test and diffuse lung capacity of patients was unchanged, whereas the exercise performance was found to have significantly improved; the mean increase in maximal oxygen consumption proved to be at 2.8 ml/kg/min (p<0.01). Eleven patients underwent lobectomy; no postoperative mortality was noted and mean hospital stay was 17 days. Postoperative pulmonary complication was recorded in 8 patients. CONCLUSIONS: Short-term preoperative pulmonary rehabilitation could improve the exercise capacity of patients with chronic obstructive pulmonary disease who are candidates for lung resection for non-small cell lung cancer.  相似文献   
110.
We performed a one-stage hybrid surgical and endovascular procedure to manage a 6.5-cm right aortic arch aneurysm associated with anomalous origin of the supra-aortic vessels in a 70-year-old man. Complete surgical rerouting of the supra-aortic vessels was followed by the endovascular repair of the right aortic arch aneurysm with a Zenith TX2 stent graft (Cook, Bloomington, Ind) and Z-track plus introducer system. The procedure was successfully completed with exclusion of the aortic arch aneurysm, and the patient was discharged on postoperative day 7. Aortic arch aneurysms with complex anatomy may be successfully treated with a less invasive hybrid approach using new generation devices.  相似文献   
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