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51.
52.
BACKGROUND: Right heart dysfunction is a major cause for early morbidity and mortality after heart transplantation. Experiments were designed to evaluate the influence of the calcium-desensitizing drug 2,3-butanedione 2-monoxime (BDM) on right heart function in a porcine model of heart transplantation. METHODS: Donor hearts of domestic pigs were arrested with BDM in Krebs solution (n = 7) and with BDM in Bretschneider's histidine-tryptophan-ketoglutarate (HTK) solution (n = 6). There were 2 control groups: University of Wisconsin (UW, n = 6) and HTK (n = 6). An isovolumic model was used in which the right ventricular volume was precisely controlled in vivo with an intracavitary high-compliance balloon. After 4 hours of ischemia, hearts were transplanted into recipients. After 1 and 2 hours of reperfusion, the right ventricular balloon volume was increased in 10-mL increments until right ventricular failure occurred and the developed pressures were recorded. RESULTS: Maximal right ventricular developed pressures were significantly different after 2 hours of reperfusion (UW: 35 +/- 13 mm Hg; HTK: 47 +/- 8 mm Hg; Krebs+BDM: 49 +/- 9 mm Hg; HTK+BDM: 50 +/- 6 mm Hg; P =.04). Hearts subjected to BDM could be loaded with a significantly increased volume after 1 hour and after 2 hours (UW: 57 +/- 10 mL vs HTK: 43 +/- 8 mL vs Krebs+BDM: 70 +/- 10 mL vs HTK+BDM: 67 +/- 15 mL; P =.002). Postischemic right ventricular enddiastolic compliance was significantly increased in groups treated with BDM after 1 hour (P =.02) and after 2 hours (P =.039). CONCLUSIONS: The drug BDM significantly improves right ventricular function in a heart transplantation model. The increase in volume load and developed right ventricular pressure achieved by BDM application would translate into a decreased risk of right ventricular failure after clinical transplantation.  相似文献   
53.

Introduction

Experience in thoracoscopic congenital diaphragmatic hernia (CDH) repair has expanded, yet efficacy equal to that of open repair has not been demonstrated. In spite of reports suggesting higher recurrent hernia rates after thoracoscopic repair, this approach has widely been adopted into practice. We report a large, single institutional experience with thoracoscopic CDH repair with special attention to recurrent hernia rates.

Methods

We reviewed the records of neonates with unilateral CDH repaired between January 2006 and February 2010 at Morgan Stanley Children's Hospital. Completely thoracoscopic repairs were compared to open repairs of the same period. In addition, successful thoracoscopic repairs were compared with thoracoscopic repairs that developed recurrence. Data were analyzed by Mann-Whitney U and Fisher exact tests.

Results

Thirty-five neonates underwent attempted thoracoscopic repair, with 26 completed. Concurrently, 19 initially open CDH repairs were performed. Preoperatively, patients in the open repair group required more ventilatory support than the thoracoscopic group. Recurrence was higher after thoracoscopic repair (23% vs 0%; P = .032). In comparing successful thoracoscopic repairs to those with recurrence, none of the factors analyzed were predictive of recurrence.

Conclusions

Early recurrence of hernia is higher in thoracoscopic CDH repairs than in open repairs. Technical factors and a steep learning curve for thoracoscopy may account for the higher recurrence rates, but not patient severity of illness. In an already-tenuous patient population, performing the repair thoracoscopically with a higher risk of recurrence may not be advantageous.  相似文献   
54.
Background. For effective palliation of patients with malignant pleural effusion due to advanced neoplastic disease, any proposed treatment should have low procedure-related mortality and morbidity.

Methods. The clinical outcome of 119 thoracoscopies in 101 patients (56 women, 45 men), from 42 to 91 years of age (mean, 68 ± 9 years) with malignant pleural effusions was evaluated in a retrospective study. Video-assisted thoracoscopy (VATS) talc pleurodesis was done in 105 instances, and a pleuroperitoneal shunt was performed 14 times as an alternative when complete expansion of the lung could not be achieved due to tumor implants on the visceral pleura.

Results. The VATS talc pleurodesis resulted in clinically significant improvement of dyspnea in 92.2% of the patients. Thirty-day mortality was 2.8% and morbidity was 2.8%. The mean duration of postoperative survival was 6.7 months. Recurrent pleural effusion occurred in 5.7% of patients after a mean interval of 6 months. Clinical relief of dyspnea was obtained in 73% of the patients treated with pleuroperitoneal shunts. Thirty-day mortality in this group was 21% and morbidity was 14.3%. The mean duration of survival was 4.2 months.

Conclusions. The VATS talc pleurodesis is appropriate for palliation of patients with malignant pleural effusions and should be performed once the diagnosis has been confirmed. Patients with lungs trapped by visceral carcinomatosis may benefit from placement of a pleuroperitoneal shunt as an alternative.  相似文献   

55.
PURPOSE: First line treatment of ureteropelvic junction obstruction is still open dismembered pyeloplasty. The development of videoendoscopic techniques like endopyelotomy and laparoscopy offers less invasive alternatives. The long-term outcome of an algorithm selectively using these techniques is presented. MATERIALS AND METHODS: From February 1995 to March 2006, 256 patients with ureteropelvic junction obstruction were treated with 113 laser endopyelotomies and 143 laparoscopic retroperitoneal pyeloplasties. According to changing selection criteria, an early group (92 in 1995 to 1999) treated with laser endopyelotomy for extrinsic as well as intrinsic stenoses, and a late group (164 in 2000 to 2006) treated with laser endopyelotomy for intrinsic stenosis, were evaluated. In the late group extrinsic ureteropelvic junction obstruction was treated with nondismembered pyeloplasty in cases of anteriorly and by dismembered pyeloplasty in cases of posteriorly crossing vessels or a redundant renal pelvis. RESULTS: Operating time of laser endopyelotomy averaged 34 (range 10 to 90) minutes with a complication rate of 5.3% and a success rate of 72.6% (intrinsic 85.7% vs extrinsic 51.4%). Operating time of laparoscopic retroperitoneal pyeloplasty averaged 124 (range 37 to 368) minutes with a 6.3% complication rate and an overall success rate of 94.4% (intrinsic 100% vs extrinsic 93.8%). In the late group the LAP success rate was 98.3% with no significant differences related to the cause of ureteropelvic junction obstruction (intrinsic 100% vs extrinsic 98.1%) or the type of pyeloplasty (YV plasty 97.0% vs Anderson-Hynes 97.7%). CONCLUSIONS: Laparoscopic retroperitoneal pyeloplasty yields an efficacy similar to that of open surgery. The inferior success of laser endopyelotomy even in optimally selected cases and the increasing expertise with endoscopic suturing may favor laparoscopic pyeloplasty with or without robotic assistance in the future.  相似文献   
56.
BACKGROUND AND METHODS: The endogenous inhibitor of nitric oxide synthase (NOs) asymmetrical dimethyl-arginine (ADMA) has been implicated as a possible modulator of inducible NOs during acute inflammation. We examined the evolution in the plasma concentration of ADMA measured at the clinical outset of acute inflammation and after its resolution in a series of 17 patients with acute bacterial infections. RESULTS: During the acute phase of inflammation/infection, patients displayed very high levels of C-reactive protein (CRP), interleukin-6 (IL-6), procalcitonin and nitrotyrosine. Simultaneous plasma ADMA concentration was similar to that in healthy subjects while symmetric dimethyl-arginine (SDMA) levels were substantially increased and directly related with creatinine. When infection resolved, ADMA rose from 0.62 +/- 0.23 to 0.80 +/- 0.18 micromol/l (+29%, P = 0.01) while SDMA remained unmodified. ADMA changes were independent on concomitant risk factor changes and inversely related with baseline systolic and diastolic pressure. Changes in the ADMA/SDMA ratio were compatible with the hypothesis that inflammatory cytokines activate ADMA degradation. CONCLUSIONS: Resolution of acute inflammation is characterized by an increase in the plasma concentration of ADMA. The results imply that ADMA suppression may actually serve to stimulate NO synthesis or that in this situation plasma ADMA levels may not reflect the inhibitory potential of this methylarginine at the cellular level.  相似文献   
57.
OBJECTIVE: The aim of this study was to evaluate soft tissue image quality of a mobile cone-beam computed tomography (CBCT) scanner with an integrated flat-panel detector. STUDY DESIGN: Eight fresh human cadavers were used in this study. For evaluation of soft tissue visualization, CBCT data sets and corresponding computed tomography (CT) and magnetic resonance imaging (MRI) data sets were acquired. Evaluation was performed with the help of 10 defined cervical anatomical structures. RESULTS: The statistical analysis of the scoring results of 3 examiners revealed the CBCT images to be of inferior quality regarding the visualization of most of the predefined structures. Visualization without a significant difference was found regarding the demarcation of the vertebral bodies and the pyramidal cartilages, the arteriosclerosis of the carotids (compared with CT), and the laryngeal skeleton (compared with MRI). Regarding arteriosclerosis of the carotids compared with MRI, CBCT proved to be superior. CONCLUSIONS: The integration of a flat-panel detector improves soft tissue visualization using a mobile CBCT scanner.  相似文献   
58.
59.

BACKGROUND CONTEXT

Anterior cervical discectomy and fusion (ACDF) without and with cervical plating (ACDF+CP) are accepted surgical techniques for the treatment of degenerative cervical disc disorders. The effect of CP on the development of adjacent segment degeneration (ASD) remains unclear.

PURPOSE

To assess whether CP accelerates the degeneration of the adjacent and adjoining segments.

STUDY DESIGN/SETTING

This is an imaging cohort study.

PATIENT SAMPLE

Retrospectively, a total of 84 patients who underwent ACDF or ACDF+CP were identified. At final follow-up, an MRI was performed and evaluated in this study.

MATERIALS AND METHODS

An MRI of 84 patients who underwent ACDF (46 patients) and ACDF+PS (38 patients) was performed. The mean follow-up was 24 years (17–45 years). None of the patients had a repeat procedure in the cervical spine. The grade of degeneration of the segments adjacent and adjoining to the fusion was assessed via a five-step grading system (segmental degeneration index, or SDI) that includes disc signal intensity, anterior and posterior disc protrusion, narrowing of the disc space, and foraminal stenosis. Furthermore, the disc height (DH) and sagittal segmental angle (SSA) of fused segments were measured.

RESULTS

A significantly (p<.001) greater SDI was identified at the caudal adjacent segment following ACDF compared to ACDF+CP. No other significant differences were identified in patients following ACDF and ACDF+CP. Between 50% and 96% of all segments showed severe degenerative changes according to SDI. There was no significant difference in DH between the patients following ACDF and ACDF+CP. The SSA in patients who underwent ACDF+CP was significantly greater than in the ACDF patients (p=.002).

CONCLUSIONS

In this cohort of patients, cervical plating had no significant impact on segmental degeneration and decrease of DH in the adjacent and adjoining segments. ACDF+CP seem to preserve the lordotic alignment more with respect to the SSA than ACDF.  相似文献   
60.
The purpose of this study was to examine the outcome of attempted radical surgical resection in patients with stage IV neuroblastoma. Between 1989 and 2003, 20 (median age 2.4 years, range 0.5–8.7 years) children with stage IV neuroblastoma were treated at the Department of Pediatrics. Surgery was performed in 7 consecutive children (6 male and 1 female) between July 1997 and February 2002 at the Department of Urology in Bonn. Mean age at diagnosis was 57 months (21–104 months). Mean age at the time of surgery was 54 months (8–390 months). Follow-up was available for all patients (100%) and mean follow-up after the operation was 32.5 months (4–56 months). Primary localization of the tumor was retroperitoneal in all cases; 4 out of 7 patients (57%) also had additional adrenal, 3 out of 7 (42%) paraganglion and 1 out of 7 (14%) thoracic primaries. Bone marrow and lymph node metastases were found in all patients (100%). Surgery led to complete tumor resection in 6 out of 7 patients (85%). Surgical approach was abdominal (chevron incision) in 6 out of 7 (85%) of the patients, in one patient the approach was thoraco-abdominal. After induction chemotherapy and delayed surgery, 6 out of 7 (86%) patients showed a complete remission (CR) and the mean CR lasted for about 27.7 months (range 3.1–55.4 months). At the last time of follow-up 5 out of 7 (71%) patients were alive, 2 had died due to recurrent disease. Mean time to recurrent disease was 24 and 51 months, respectively. Mean overall survival time since diagnosis was 38.3 months (11–64 months) and mean event-free survival was 34.5 months (11–60.3 months). The final outcome, overall survival and event-free survival time was influenced by metastatic or local relapse. Tumor resection is beneficial but the value of surgery can only be judged when we are able to control metastatic disease in stage IV neuroblastoma. The final outcome may rely on the extent of complete surgical resection, but is also related to treatment of metastases. A longer follow-up period is indicated to detect long term outcome.  相似文献   
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