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51.

Objective

Little is known about the outcomes of aortic root operations that involve inducing hypothermic circulatory arrest for relatively extensive proximal aortic surgery. We attempted to identify predictors of postoperative hospital length of stay (LOS) and factors that affect postoperative recovery.

Methods

During 2006-2014, 247 of 265 patients (93.2%) with disease extending into the aortic arch survived aortic root operations (206 elective, 41 urgent/emergent) in which hypothermic circulatory arrest with moderate hypothermia was used. Stepwise multivariate regression analysis was performed to identify predictors of LOS (as a continuous variable) and prolonged LOS (defined as LOS >9 days, the median for the cohort). By this definition, 111 patients (45%) had prolonged LOS and 136 (55%) did not.

Results

Preoperative factors that independently predicted longer LOS in the entire cohort included age (P = .0014), redo sternotomy (P = .0047), and intraoperative packed red blood cell (PRBC) transfusion (P = .0007). Redo sternotomy and intraoperative PRBC transfusion also predicted longer LOS in 3 subgroup analyses: one of elective cases, one from which total arch replacement procedures were excluded, and one limited to patients who were discharged home. Age predicted longer LOS in the non-total arch (hemiarch) replacement patients. Ventilator support >48 hours (P < .0001) was associated with longer LOS. Elective aortic valve?sparing root replacement predicted a shorter LOS than valve replacement in multivariate regression analysis (P = .028).

Conclusions

In patients undergoing aortic root surgery with hypothermic circulatory arrest for disease extending into the aortic arch, reducing intraoperative PRBC transfusion except when absolutely necessary may reduce postoperative LOS and expedite recovery. Performing aortic valve–sparing root replacement, when feasible, may also reduce LOS.  相似文献   
52.
Avascular necrosis of the femoral head is the most serious complication after closed reduction in developmental dysplasia of the hip. Although arthrography has a well-established role in the treatment of developmental dysplasia of the hip, its use is not universal. A prospective study was conducted to compare the incidence of avascular necrosis after closed reduction in developmental dysplasia of the hip performed with and without arthrography in 85 patients, with a minimum of 5 years follow up. Arthrographic criteria were evaluated including lateralization of the femoral head and the type of limbus encountered. Hips treated by closed reduction based on arthrographic evaluation had significantly less incidence of avascular necrosis when compared with those treated by closed reduction without arthrographic guidance. Closed reduction with lateralization of more than 4 mm, and those hips with an inverted limbus were associated with an increased risk of avascular necrosis.  相似文献   
53.
The purpose of this experimental study was to evaluate possible upgrading effects of systemic creatine monohydrate administration on the reinnervation of denervated muscle. At the same time, the protective effect of the agent on denervated muscle until ultimate reinnervation after nerve repair was quantified. The functional outcome of muscle reinnervation after creatine monohydrate application was compared with a control group. Forty adult Wistar rats weighing 180 to 220 g were used. The right sciatic nerve was dissected, exposed, and cut at the level of the midthigh in all rats. The experimental design consisted of two groups: experimental (animals were fed creatine monohydrate) and control (gavage feeding was provided by saline). Both groups were divided into two subgroups: subgroups A and B for the experimental group, and subgroups C and D for the control group. In subgroups A and C, the nerves were repaired with four 10-0 epineurial stitches. In subgroups B and D, both the proximal and distal ends of the nerves were ligated and no neural anastomosis was performed. In the experimental groups (subgroups A and B), the rats were fed by daily supplementation of oral creatine monohydrate, 300 mg/kg body weight. In the controls (subgroups C and D), oral supplementation was provided by saline. Functional recovery was evaluated using walking track analysis, pinching test, and limb circumference and toe contracture measurements at the end of 6 months, after which the rats were sacrificed and nerve specimens from both ends of the repair sites and the whole gastrocnemius muscle were obtained to document the results of the histomorphometric and histochemical studies, including light microscopic examinations and muscle weight measurements. The mean functional recovery values in subgroups A, B, C, and D were 91 percent, 80 percent, 87 percent, and 59 percent, respectively. Functional recovery improved significantly in the experimental groups (in both the surgically repaired and unrepaired subgroups), compared with the control groups (p<0.05). The pinching test revealed a statistically significant difference in nerve conduction between the experimental and control groups (p<0.05). The limb circumference ratio of the surgically treated side to the untouched side in subgroups A, B, C, and D were noted as 0.95, 0.89, 0.91, and 0.87, respectively, and the difference between the experimental and the control groups was statistically significant (p<0.05). The differences between subgroups A and B, C and D, A and C, and B and D were also significant. The surgically repaired and creatine-supplemented subgroups demonstrated the best results in toe contracture index. The muscle weight measurement results were concordant with the results of the limb circumference ratio. In both surgically repaired subgroups (subgroups A and C), there were qualitatively significant amounts of myelinated fibers in the nerve distal to the anastomotic site; there were no myelinated fibers in the distal stumps of subgroups B and D. Histochemical analyses of the contents of the muscle fiber types also revealed no significant difference. Overall, the results showed the useful effect of oral creatine supplementation on both surgically repaired and unrepaired nerve injuries. The best results were obtained from surgically repaired nerve injuries and also from the systemic creatine-supplemented subgroups. This study confirms that systemic administration of creatine monohydrate has a protective and upgrading effect on the functional properties of denervated muscle, especially in surgically reinnervated subjects.  相似文献   
54.

Background/Purpose

Perfusion imaging redefines computed tomography (CT) as a technique that can now depict vascular physiology in addition to detailed anatomy. The major clinical applications of perfusion CT are in acute stroke and oncology. Currently, there are very limited data on the application of perfusion CT in urology. The aim of the present study is to investigate the potential value of perfusion CT in anatomic and functional evaluation of obstruction in a single session on experimental hydronephrosis model in rats. Thus, we evaluate the perfusion CT in a new clinical application.

Methods

Twenty-eight rats were randomly allocated into 4 groups each consisting of 7 rats. At the third week of experimental intervention, postoperative renogram curves and perfusion parameters of the right kidneys' cortex and pelvis were assessed by CT. The right ureter was sutured as proximal complete obstruction in group 1, as distal complete obstruction in group 2, and as proximal partial obstruction in group 3. Group 4 served as the sham control group. Computed tomography was performed with single-slice tomography. Dynamic examination was performed with the help of perfusion software through contrast-enhanced tomography examination.

Results

In all study groups, the aorta time/density curves showed a rapid increase after a rapid decrease, and the duration to reach peak concentration in the normal kidney cortex was observed to be later than the aorta as expected. In groups 1, 2, and 3, the duration to reach peak concentration lengthened and the peak concentration values decreased. The time/density curves gradually increased as a result of the accumulation of the contrast agent in the pelvis, and a peak was observed at the end of the procedure in all study groups. In groups 1, 2, and 3, a statistically significant decrease (P = .01, P = .01, and P = .01, respectively) was observed in the peak concentration values of the contrast agent in comparison to group 4. The flow and blood volume values gradually decreased as the grade of the obstruction increased and the localization of the obstruction or grade of obstruction moved closer to the kidney.

Conclusion

In conclusion, perfusion CT technique, performed in a single session, is a useful method for anatomic visualization, together with functional evaluation, in the diagnosis of ureteric obstructive pathology of experimental hydronephrosis model.  相似文献   
55.
Methods:Data on 11 robot-assisted laparoscopic partial nephrectomies performed by using our technique from February 2015 through June 2015 were retrospectively analyzed. The robotic platform used was DaVinci Xi (Intuitive Surgical, Inc., Sunnyvale, California, USA) with a 3-arm setup. The AirSeal system (SurgiQuest, Milford, Connecticut, USA) was used as a port allowing simultaneous introduction of 2 instruments for the bedside surgeon, obviating the need for an additional (fourth) robotic arm. A long suction-and-irrigation device and atraumatic grasping forceps were used. Both instruments were introduced through the trocar of the AirSeal system, making simultaneous introduction and use possible. We preferred the long suction-and-irrigation device, because it minimizes collision of the instruments.Results:Mean age and BMI of the patients were 55 ±14.6 y and 29.18 ± 6.85, respectively. Seven tumors were on the right side and 4 were on the left. The mean size of the tumors was 32.45 mm (± 11.31). Surgical time was 132.2 minutes (±37.17), with an estimated blood loss and ischemia time of 103.63 mL (±65.92) and 16.72 minutes (±9.52), respectively. One patient had postoperative bleeding that was resolved without transfusion. The median hospitalization period was 3.9 d (±0.53). Loss of intra-abdominal pressure was not observed, and pressure was stable at 10 mm Hg.Conclusion:The AirSeal System and its valveless trocar eliminated the need for an additional port placement in our series. The technique is feasible, safe, and reproducible; therefore, it may be implemented in selected cases of robot-assisted partial nephrectomies.  相似文献   
56.
Background Preoperative parenchymal or peritumoral (PT) injection of 99mTc-labeled sulfur colloid (TcSC) is the standard method for sentinel lymph node (SLN) identification in patients with breast cancer. Limitations of this method include variable identification rates, slow transit times, and painful injections. We hypothesize that TcSC will travel to the SLN within minutes after injection into the subareolar (SA) lymphatics, thus making an intraoperative injection technique feasible.Methods One hundred twenty-two women with invasive breast cancer were enrolled onto this prospective study. Immediately after the induction of general anesthesia, patients were injected with 1 to 2 mCi of filtered TcSC in the SA location. Then, 5 mL of 1% isosulfan blue dye was injected into the PT location. The SLN or SLNs were identified as radioactive, blue, or both and removed for pathologic evaluation.Results The mean patient age was 56 years. The mean tumor size was 1.5 cm. In 86.1% of patients, a transcutaneous axillary hot spot was identified by handheld gamma probe. The mean time from TcSC injection to axillary incision was 17.6 minutes. At least one SLN was identified in 99.2% of patients. The mean number of SLNs identified per patient was 1.83. The mean count of radioactive SLNs was 2715 cps. In 97.2% of patients, blue SLNs were also radioactive.Conclusions TcSC injected into the SA lymphatics rapidly drains to the SLN. The radioactive SLN is easily and quickly identified after an intraoperative SA TcSC injection. The simplicity of this method eliminates the inherent problems associated with standard PT injection.  相似文献   
57.
This retrospective study summarizes our experience based on treating 62 patients with trigeminal neuralgia treated with microvascular decompression. All patients had typical trigeminal neuralgia symptoms, with 24 of them (38%) having failed to benefit from other previous treatment paradigms. We excluded subjects with atypical and/or secondary forms of trigeminal neuralgia. Follow-up duration ranged from 5 months to 10 years 6 months, with recurrence being identified in three patients (4.8%).We found that the superior cerebellar artery is the leading offending vessel in our cases (33.9%; 21 patients). Interestingly, seven patients (11.3%) underwent an early reoperation 12-48 h later after the first operation was deemed ineffective. This subgroup recovered satisfactorily following isolation of the pathogenic vessels. Overall, no mortality was observed in our patients, and the only permanent morbidity outcome was a case of facial nerve palsy (1.6%). We conclude that microvascular decompression and its reapplicaiton for patients who showed no pain relief immediately after the first decompression are safe and effective treatments for trigeminal neuralgia.  相似文献   
58.
59.
Sir, Various infectious agents have been reported to cause rhabdomyolysis[1–5]. We present a case of acute Brucella infection,complicated with recurrent rhabdomyolysis and mild renal failure. A 39-year old man was admitted to hospital because of muscularpain and dark urine. Ciprofloxacine was begun 1 day before hisreferral with the possible diagnosis of urinary infection. Hereported consumption of unpasteurized milk  相似文献   
60.
PURPOSE: In this prospective study we evaluated the incidence of bladder perforation after transurethral bladder tumor resection. MATERIALS AND METHODS: A total of 36 patients (33 male, 3 female, mean age +/- SD 65.6 +/- 11.43 [range 26 to 81]) with a solid mass in the bladder (mean 20.3 +/- 8.7 mm, range 5 to 40) were included in the study. Transurethral resections were performed with a 24Fr resectoscope. After the procedure an 18Fr Foley catheter was inserted into the bladder and 400 ml of 1/4 saline diluted contrast solution was instilled under gravity from 60 cm above the bladder. Complete filling and post-drainage radiographs were taken and examined for any evidence of extravasation. Regular evaluations with cystoscopy and ultrasound/computerized tomography were done to detect possible tumor recurrence and perivesical seeding. RESULTS: Histopathological examination of the tumors showed transitional cell carcinoma in 35 patients and chronic eosinophilic cystitis in 1. Review of the cystograms revealed various degrees of extraperitoneal contrast extravasation around the resected area in 21 patients (58.3%). The only statistically significant difference between patients with and without extravasation was in tumor size (logistic stepwise regression p = 0.030,) among factors tested including patient age and localization, number of foci, tumor grade and stage. No apparent clinical problems requiring medical or surgical intervention other than urethral catheterization developed and no evidence of extravesical tumor seeding as per ultrasound and/or computerized tomography was seen during a mean followup of 21.9 months (range 7 to 40). CONCLUSIONS: The extravasation of urine (asymptomatic perforation) after transurethral bladder tumor resection may occur much more frequently than believed or reported. It seems that this extravasation does not impose a significant risk of extravesical tumor seeding.  相似文献   
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