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101.
102.
OBJECTIVE: Outcome after prolonged normovolemic cardiac arrest is poor, and new resuscitation strategies have to be found. We hypothesized that the induction of deep hypothermia for emergency preservation and resuscitation (EPR) during prolonged cardiac arrest, before the start of reperfusion, will mitigate the deleterious cascades leading to neuronal death and will thus improve outcome. DESIGN: Prospective experimental study. SETTING: University research laboratory. SUBJECTS: Thirteen pigs, Large White breed (27-37 kg). INTERVENTIONS: After 15 mins of ventricular fibrillation, pigs were subjected to 1) EPR (n = 6), 20 mins of hypothermic stasis induced with a cold saline aortic flush; or 2) 20 mins of conventional resuscitation (n = 7). Then cardiopulmonary bypass was initiated in both groups, followed by defibrillation. Controlled ventilation and mild hypothermia were continued for 20 hrs; survival was for 9 days. For neurologic evaluation, neurologic deficit score (100% = brain dead, 0-10% = normal), overall performance category (1 = normal, 5 = dead or brain dead), and brain histologic damage score were used. MEASUREMENTS AND MAIN RESULTS: In the EPR group, brain temperature decreased from 38.5 degrees C +/- 0.2 degrees C to 16.7 degrees C +/- 2.5 degrees C within 235 +/- 27 secs. Five animals achieved restoration of spontaneous circulation and survived to 9 days: two pigs with overall performance category 2 and three pigs with overall performance category 3. Their neurologic deficit score was 45% (interquartile range 35, 50) and histologic damage score was 142 (interquartile range 109, 159). In the control group, four pigs achieved restoration of spontaneous circulation: one survived to 9 days with overall performance category 3, neurologic deficit score 45%, and histologic damage score 226 (restoration of spontaneous circulation, p = .6; survival, p = .03; overall performance category, p = .02). CONCLUSIONS: EPR is feasible in an experimental pig model and improves survival after prolonged cardiac arrest in pigs. Further experimental studies are needed before this concept can be brought into clinical practice.  相似文献   
103.
Barth  Udo  Meyer  Frank  Halloul  Zuhir 《Der Chirurg》2022,93(10):966-975
Die Chirurgie - Es sollen die komplexen Veränderungen in der gefäßchirurgischen Lehre, Gemeinsamkeiten/Unterschiede zur Allgemeinchirurgie, Spezifika der Lehre/Lehrinhalte sowie...  相似文献   
104.

Abstract

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Introduction

Solitary bone plasmacytoma (SP) is a rare diagnosis for which the primary treatment is local radiotherapy. There is no established consensus suggesting a total spondylectomy in spinal SP.

Materials and Methods

We report the case of a 43-year-old woman with solitary plasmacytoma of the lumbar spine treated with complete vertebral resection. Radiographs, CT scan and MRI showed a single osteolytic lesion of the third lumbar vertebra. Further diagnostics following recommended algorithm for tumour screening were negative. Two times, biopsy showed no histological pathologies. Due to the instability of the spine with suspicious unknown lesion, we decided to perform a dorsal lumbar approach and instrumentation with complete resection of the posterior parts to prepare for a complete resection if mandatory. Resamples were taken and the bone surfaces sealed. Consecutive findings were positive for plasma cell infiltration of the respective vertebra, however not on the first pass, but after diagnostic pathological reference. Surgery was completed by total spondylectomy. Reference histological findings with restaging and cytogenetic risk analysis confirmed a non-high-risk solitary bone plasmacytoma, and the patient was scheduled for localized radiotherapy with 40 Gy.

Results

Follow-up examinations (53 months) showed no local recurrence or disease progression.

Discussion

There is no consensus in the literature regarding appropriate surgical approach and perioperative strategies in the treatment of solitary plasmacytoma. The finding of a solitary plasmacytoma of the spine was the determining factor for our decision to perform radical surgery with subsequent radiotherapy. The rationale for the chosen approach was to minimize the risk of local recurrence and to avoid conversion into multiple myeloma. The follow-up with 53 months is limited. However, discussion remains, if radical surgery in addition to local radiotherapy could be an alternative therapeutic approach depending on paraclinical parameters, age and cytogenetic risk analysis.  相似文献   
105.

Background

This update of a randomized, prospective study presents the effect of external beam radiation therapy (EBRT) on long-term overall survival, local control, and limb function following limb-sparing surgery (LSS) for the treatment extremity soft tissue sarcoma (STS).

Methods

Following LSS, patients with extremity STS were randomized to receive EBRT or surgery alone. All patients with high-grade STS received adjuvant chemotherapy. Long-term follow-up was obtained through telephone interviews using a questionnaire based on validated methods. Overall survival (OS) was determined by Kaplan–Meier method.

Results

A total of 141 patients with extremity STS were randomized to receive adjuvant EBRT (n = 70) or LSS alone (n = 71). Median follow-up was 17.9 years. The 10- and 20-year survival was 77 % (95 % CI 66–85 %) and 64 % (95 % CI 52–75 %) for patients receiving LSS alone and 82 % (95 % CI 72–90 %) and 71 % (95 % CI 59–81 %) for patients receiving EBRT (p = 0.22). Of the 54 patients who completed telephone interviews, the incidence of local recurrence during the follow-up period was 4 % (1 of 24) in the LSS alone cohort compared with 0 % (0 of 30) in those who received EBRT (p = 0.44). Patients treated with EBRT tended to have more wound complications (17 vs. 12.5 %, p = 0.72), clinically significant edema (25 vs. 12 %, p = 0.31), and functional limb deficits (15 vs. 12 %, p = 0.84).

Conclusions

Adjuvant EBRT following surgery for STS of the extremity provides excellent local control with acceptable treatment-related morbidity and no statistically significant improvement in overall survival.  相似文献   
106.
This study investigated whether reperfusion results in an increase of ultrastructurally determined myocardial injury in pig hearts. The left anterior descending coronary artery (LAD) was distally occluded in 12 pigs for 35–45 minutes and then reperfused for 3 hours. At the end of ischemia, as well as after 3 hours of reperfusion, one transmural biopsy was removed from the center of the risk region and subdivided into four specimens, representing the subendocardial (I), subendo-midmyocardial (II), subepi-midmyocardial (III), and subepicardial layers (IV). The degree of injury was assessed by electronmicroscopy and was scored as reversible (1), an almost equal mixture of reversible and irreversible (2), and totally irreversible (3) damage. In addition, infarct size was determined as the ratio of infarcted (tetrazolium stain) to ischemic (dye technique) myocardium. Infarct sizes ranged from 29.3% to 93% (mean 61.2%). The scores of injury of the four tissue layers before and after reperfusion did not differ significantly: layer I, 2.4 ± 0.8/2.3 ± 0.9; layer II, 2.2 ± 0.9/2.0 ± 0.9; layer III, 1.8 ± 0.9/2.0 ± 0.9; and layer IV, 1.6 ± 0.9/1.3 ± 0.6. The means of the four layers were almost identical at the end of ischemia (2.1 ± 0.8) and after 3 hours of reperfusion (2.0 ± 0.6). A linear regression analysis with 95% confidence limits of the score values before and after reperfusion indicated that maximally 25% of a mean final infarct size of about 50% may be due to lethal reperfusion injury. This study suggests that cell death in regional ischemia and reperfusion occurs predominantly during ischemia and not during reperfusion.  相似文献   
107.
Conventional univariate statistics are common and widespread in neuroimaging research. However, functional and structural MRI data reveal a multivariate nature, since neighboring voxels are highly correlated and different localized brain regions activate interdependently. Multivariate pattern classification techniques are capable of overcoming shortcomings of univariate statistics. A rising interest in such approaches on neuroimaging data leads to an increasing demand of appropriate software and tools in this field. Here, we introduce and release MANIA—Machine learning Application for NeuroImaging Analyses. MANIA is a Matlab based software toolbox enabling easy pattern classification of neuroimaging data and offering a broad assortment of machine learning algorithms and feature selection methods. Between groups classifications are the main scope of this software, for instance the differentiation between patients and controls. A special emphasis was placed on an intuitive and easy to use graphical user interface allowing quick implementation and guidance also for clinically oriented researchers. MANIA is free and open source, published under GPL3 license. This work will give an overview regarding the functionality and the modular software architecture as well as a comparison between other software packages.  相似文献   
108.
Autosomal recessive polycystic kidney disease (ARPKD), although less frequent than the dominant form, is a common, inherited ciliopathy of childhood that is caused by mutations in the PKHD1-gene on chromosome 6. The characteristic dilatation of the renal collecting ducts starts in utero and can present at any stage from infancy to adulthood. Renal insufficiency may already begin in utero and may lead to early abortion or oligohydramnios and lung hypoplasia in the newborn. However, there are also affected children who have no evidence of renal dysfunction in utero and who are born with normal renal function. Up to 30 % of patients die in the perinatal period, and those surviving the neonatal period reach end stage renal disease (ESRD) in infancy, early childhood or adolescence. In contrast, some affected patients have been diagnosed as adults with renal function ranging from normal to moderate renal insufficiency to ESRD. The clinical spectrum of ARPKD is broader than previously recognized. While bilateral renal enlargement with microcystic dilatation is the predominant clinical feature, arterial hypertension, intrahepatic biliary dysgenesis remain important manifestations that affect approximately 45 % of infants. All patients with ARPKD develop clinical findings of congenital hepatic fibrosis (CHF); however, non-obstructive dilation of the intrahepatic bile ducts in the liver (Caroli’s disease) is seen at the histological level in only a subset of patients. Cholangitis and variceal bleeding, sequelae of portal hypertension, are life-threatening complications that may occur more often in advanced cases of liver disease. In this review we focus on common and uncommon kidney-related and non-kidney-related phenotypes. Clinical management of ARPKD patients should include consideration of potential problems related to these manifestations.  相似文献   
109.

OBJECTIVE:

Videolaryngoscopy has mainly been developed to facilitate difficult airway intubation. However, there is a lack of studies demonstrating this method''s efficacy in pediatric patients. The aim of the present study was to compare the TruView infant EVO2 and the C-MAC videolaryngoscope with conventional direct Macintosh laryngoscopy in children with a bodyweight ≤10 kg in terms of intubation conditions and the time to intubation.

METHODS:

In total, 65 children with a bodyweight ≤10 kg (0-22 months) who had undergone elective surgery requiring endotracheal intubation were retrospectively analyzed. Our database was screened for intubations with the TruView infant EVO2, the C-MAC videolaryngoscope, and conventional direct Macintosh laryngoscopy. The intubation conditions, the time to intubation, and the oxygen saturation before and after intubation were monitored, and demographic data were recorded. Only children with a bodyweight ≤10 kg were included in the analysis.

RESULTS:

A total of 23 children were intubated using the C-MAC videolaryngoscope, and 22 children were intubated using the TruView EVO2. Additionally, 20 children were intubated using a standard Macintosh blade. The time required for tracheal intubation was significantly longer using the TruView EVO2 (52 sec vs. 28 sec for C-MAC vs. 26 sec for direct LG). However, no significant difference in oxygen saturation was found after intubation.

CONCLUSION:

All devices allowed excellent visualization of the vocal cords, but the time to intubation was prolonged when the TruView EVO2 was used. The absence of a decline in oxygen saturation may be due to apneic oxygenation via the TruView scope and may provide a margin of safety. In sum, the use of the TruView by a well-trained anesthetist may be an alternative for difficult airway management in pediatric patients.  相似文献   
110.
Transcortical and cervical magnetic stimulation is a potential method of examining the central inspiratory pathway to phrenic motor neurons. The reliability and accuracy of this technique were studied. We performed magnetic stimulations of the cortex and cervical spinal cord with recording from both hemidiaphragms in 35 normal subjects using two different stimulation coils (90-mm circular coil and 70-mm figure-eight coil). Needle electrode recordings and ultrasound real-time documentation in 2 subjects excluded volume-conducted contaminations from adjacent chest wall and abdominal muscles. The effect of diaphragmatic facilitation (stimulation at the end of a deep breath) on latency, and amplitude were compared to the effect of hypothenar muscle facilitation. Normal ranges were established for: latency; central motor conduction time; amplitude; amplitude ratio between peripheral and both cortical and cervical amplitude; and excitability threshold. The latencies were similar for both coils. The amplitudes were significantly higher, and excitability thresholds significantly lower for the 90-mm circular coil, indicating that this coil is preferable for transcortical diaphragmatic stimulations. The effect of facilitation was greater for hypothenar than diaphragmatic recordings. There was excellent right-left agreement for all measurements. Transcortical and cervical magnetic stimulation with recording from the diaphragm can be used routinely to diagnose and monitor patients with impaired central respiratory drive. © 1996 John Wiley & Sons, Inc.  相似文献   
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