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991.

Background

Transcatheter aortic valve replacement (TAVR) is an alternative to surgical aortic valve replacement (SAVR) for the treatment of aortic stenosis in patients at intermediate, high, and extreme risk for mortality from SAVR. We examined recent trends in aortic valve replacement (AVR) in Michigan.

Methods

The Michigan Society of Thoracic and Cardiovascular Surgeons Quality Collaborative (MSTCVS‐QC) database was used to determine the number of SAVR and TAVR cases performed from January 2012 through June 2017. Patients were divided into low, intermediate, high, and extreme risk groups based on STS predicted risk of mortality (PROM). TAVR patients in the MSTCVS‐QC database were also matched with those in the Transcatheter Valve Therapy Registry to determine their Heart Team‐designated risk category.

Results

During the study period 9517 SAVR and 4470 TAVR cases were performed. Total annual AVR volume increased by 40.0% (from 2086 to 2920), with a 13.3% decrease in number of SAVR cases (from 1892 to 1640) and a 560% increase in number of TAVR cases (from 194 to 1280). Greater than 90% of SAVR patients had PROM ≤8%. While >70% of TAVR patients had PROM ≤ 8%, they were mostly designated as high or extreme risk by a Heart Team.

Conclusions

During the study period, SAVR volume gradually declined and TAVR volume dramatically increased. This was mostly due to a new group of patients with lower STS PROM who were designated as higher risk by a Heart Team due to characteristics not completely captured by the STS PROM score.  相似文献   
992.
Eleven patients suffering severe traumatic respiratory insufficiency were mechanically ventilated using a new system which combined high-frequency positive-pressure ventilation (HFPPV) with low-rate conventional mechanical ventilation (LRCMV). Ten similar patients were ventilated by conventional mechanical ventilation (CMV) with PEEP. HFPPV patients were fully conscious and cooperative during ventilation and did not need sedatives or muscle relaxants. Arterial oxygenation was significantly (p less than .005) better in HFPPV than CMV patients (89.91 +/- 10.24 vs. 78.43 +/- 11.13 torr, respectively), and pulmonary shunt was also better in the HFPPV group (13.1 +/- 4.7% vs. 20.4 +/- 6.4%, p less than .01). Moreover, inspired oxygen concentrations were lower (PaO2/FIO2 197.8 +/- 51.3 in the HFPPV group vs. 130 +/- 46.6 in the CMV group, p less than .005) and the time required for mechanical ventilation was shorter (4.2 +/- 0.91 vs. 6.1 +/- 0.8 days, p less than .1). All HFPPV patients immediately began breathing spontaneously when they were disconnected from the ventilator. We suggest this method as a better ventilatory mode for patients suffering traumatic respiratory insufficiency.  相似文献   
993.

Background

There are numerous studies discussing thromboprophylaxis after total joint arthroplasty (TJA), with varying conclusions. Patient inclusion criteria may be different for each study, which may lead to selection bias and misrepresentation of data. This study aimed to investigate if industry funding impacted patient demographics and overall reported outcomes of studies analyzing venous thromboembolism (VTE) prevention after TJA.

Methods

Electronic searches were completed using Ovid, PubMed, and Embase databases. Studies were included if (1) they are published in the English language between 2000 and 2016; (2) they included patients undergoing total hip arthroplasty (THA) or total knee arthroplasty (TKA); and (3) they evaluated prevention and control of postoperative VTE with at least one of the following thromboprophylactic agents: aspirin, enoxaparin, dalteparin, dabigatran, apixaban, rivaroxaban, dabigatran, ximelagatran, fondaparinux, or coumadin. Data were extracted and analyzed via mixed-effect logistic regression.

Results

Fifty-seven studies were included; 29 were industry funded, and 28, nonfunded. There were no significant differences between patient's age, body mass index, or revision exclusions between funded and nonfunded studies. Funded studies reported less pulmonary embolisms, fewer events of major bleeding, and significantly less 90-day mortality compared with nonfunded studies.

Conclusion

Industry-funded studies reported less pulmonary embolisms, major bleeding, and mortality compared with nonfunded studies. Detailed demographic data were missing from the literature, and we were unable to demonstrate the cause of different reported outcomes between industry-funded and nonfunded studies. Further investigations should be aimed toward understanding how funded studies report less adverse outcomes in analyzing VTE after TJA.  相似文献   
994.

Purpose

The purpose of the study was to investigate the predictive value of stone measurements by including a novel method on non-contrast computed tomography (NCCT) images for stone composition.

Methods

We retrospectively evaluated patients who had stone analysis, NCCT images, and underwent percutaneous nephrolithotomy between 2013 and 2016. Patient characteristics, stone measurements on NCCT images, and stone analysis results were evaluated. Hounsfield unit (HU) values (maximum (HUmax), minimum (HUmin), and average (HUave) of HU values) were investigated on NCCT images. HUdiff was calculated as the difference between the HUmax and the HUmin values. Patients were divided into seven stone groups and data were compared. Then patients were separately divided into two groups according to mineral complexity (mono-mineral and multi-mineral groups) and calcium-based (calcium and other stone groups) evaluation.

Results

In the study, 115 patients were evaluated. Age, gender, HUmin, HUmax, and HUave were significantly different between the stone groups. HUdiff and HUave were found to be 341.5 HU (AUC?=?0.719, p?=?0.017) and 1051.5 HU (AUC?=?0.701, p?=?0.029) as cut-off, respectively. Seventy of 72?>?341.5 HUdiff patients and 64 of 67?>?1051.5 HUave patients had multi-mineral stones (p?=?0.001, OR 9.26, and p?=?0.028, OR 4.27), respectively. In multivariate analysis, >?341.5 HUdiff rate was significantly higher in multi-mineral and calcium stone groups; HUave was also significantly higher in the calcium stone group.

Conclusions

HUdiff and HUave were significant predictors of mineral complexity. HUdiff of <?341.5 HU showed 81.8% sensitivity and 67.2% specificity for identification of mono-mineral stones.
  相似文献   
995.

Background

Papillary muscle rupture (PMR) is a rare complication of a myocardial infarction. The aim of this study was to review our results of mitral valve surgery for acute PMR.

Methods

Data from patients undergoing emergent mitral valve surgery for acute PMR between 2011 and 2017 at our institution were reviewed. Outcomes included operative morbidity and mortality, mitral valve reoperation, and hospital readmission.

Results

A total of 2479 patients underwent mitral valve surgery during the study period including 24 (1.0%) for PMR. Mean age was 62 years, and two (8.3%) patients had prior open‐heart surgery. Overall Society of Thoracic Surgeons predicted risk of mortality was 17.5%. Operative mortality was 12.5% (n = 3) with an observed‐to‐expected mortality ratio of 0.71. There were no strokes, and new onset dialysis was required in two (8.3%) patients. Mean follow‐up was 2.40 ± 1.96 years. Three‐year mortality, mitral valve reoperation, and readmission rates were 21.1%, 5.0%, and 45.4%.

Conclusions

Expeditious operative intervention for PMR can be associated with acceptable operative and longer‐term outcomes.  相似文献   
996.
A predictive model for survival after in-hospital cardiopulmonary arrest   总被引:5,自引:0,他引:5  
BACKGROUND: In-hospital cardiopulmonary resuscitation (CPR) has seen a steady increase in the application of technology and techniques since the introduction of closed cardiac massage in 1960. Despite this progress, there has not been a demonstrated improvement in survival rates after in-hospital cardiac arrest over the last 40 years. Identification of prognostic factors associated with survival after a resuscitation attempt can help physician decisions and patients' end-of-life choices in a pre-arrest situation. METHODS: Using an Utstein-based template we analyzed 219 consecutive adult attempted resuscitations in a large urban teaching hospital over a 3-year period. The main outcome measures were survival to discharge, 1 and 3 months. Backwards stepwise logistic regression was used to select baseline variables that predict survival at discharge, 1 and 3 months. RESULTS: Survival rates at discharge, 1 and 3 months were 15.1, 13.3, and 11.5%. Meaningful neurological status (cerebral performance score of 1) at discharge was achieved in 61% of survivors. Independent predictors of survival were: higher body-mass index (BMI), presence of chronic renal insufficiency (CRI), respiratory arrest, ventricular tachycardia/fibrillation (VT/VF) as initial rhythm and arrest early during the hospital stay. A risk model based on these variables demonstrated a significant fit between predicted and observed survival at discharge with goodness of fit test P-value of 0.87. CONCLUSIONS: Survival after in-hospital cardiopulmonary arrest is poor and can be estimated by using clinical variables. If validated in a large prospective trial, this score could help physicians in attempting resuscitation, patients and families in making end-of-life decisions and hospitals in resource allocation.  相似文献   
997.

Background Context

Degenerative cervical myelopathy (DCM) is a progressive degenerative spine disease and the most common cause of spinal cord impairment in adults worldwide. Few studies have reported on regional variations in demographics, clinical presentation, disease causation, and surgical effectiveness.

Purpose

The objective of this study was to evaluate differences in demographics, causative pathology, management strategies, surgical outcomes, length of hospital stay, and complications across four geographic regions.

Study Design/Setting

This is a multicenter international prospective cohort study.

Patient Sample

This study includes a total of 757 symptomatic patients with DCM undergoing surgical decompression of the cervical spine.

Outcome Measures

The outcome measures are the Neck Disability Index (NDI), the Short Form 36 version 2 (SF-36v2), the modified Japanese Orthopaedic Association (mJOA) scale, and the Nurick grade.

Materials and Methods

The baseline characteristics, disease causation, surgical approaches, and outcomes at 12 and 24 months were compared among four regions: Europe, Asia Pacific, Latin America, and North America.

Results

Patients from Europe and North America were, on average, older than those from Latin America and Asia Pacific (p=.0055). Patients from Latin America had a significantly longer duration of symptoms than those from the other three regions (p<.0001). The most frequent causes of myelopathy were spondylosis and disc herniation. Ossification of the posterior longitudinal ligament was most prevalent in Asia Pacific (35.33%) and in Europe (31.75%), and hypertrophy of the ligamentum flavum was most prevalent in Latin America (61.25%). Surgical approaches varied by region; the majority of cases in Europe (71.43%), Asia Pacific (60.67%), and North America (59.10%) were managed anteriorly, whereas the posterior approach was more common in Latin America (66.25%). At the 24-month follow-up, patients from North America and Asia Pacific exhibited greater improvements in mJOA and Nurick scores than those from Europe and Latin America. Patients from Asia Pacific and Latin America demonstrated the most improvement on the NDI and SF-36v2 PCS. The longest duration of hospital stay was in Asia Pacific (14.16 days), and the highest rate of complications (34.9%) was reported in Europe.

Conclusions

Regional differences in demographics, causation, and surgical approaches are significant for patients with DCM. Despite these variations, surgical decompression for DCM appears effective in all regions. Observed differences in the extent of postoperative improvements among the regions should encourage the standardization of care across centers and the development of international guidelines for the management of DCM.  相似文献   
998.
Therapeutic plasma exchange in a single center: Ibni Sina experience   总被引:4,自引:0,他引:4  
BACKGROUND: The number of therapeutic procedures is increasing steadily year by year with growing collaboration of departments other than Hematology. In the aim to demonstrate our single center activity we analyzed our data since four years. METHODS: Between years 1998 and 2001, 658 therapeutic plasma exchange (TPE) procedures were performed on 158 patients. Median age and male/female ratio were 37 (range, 15-87) and 80/78, respectively. Main indications were myastenia gravis (n=55, 34%), TTP (n=13, 8.5%), post ABO mismatched allogeneic hematopoietic cell transplantation aregeneratoric anemia (n=6, 7.5%), progressive systemic sclerosis (n=10, 6.5%), multiple myeloma (n=10, 6.5%), Gullian Barre Syndrome (n=9, 5.9%), multiple sclerosis (n=7, 4.6%), Waldenstr?m Macroglobulinemia (n=5, 3.4%), polymyositis (n=4, 2.7%), sepsis and disseminated intravascular coagulation (n=4, 2.7%). Departments who referred the majority of the patients for TPE were neurology (n=199), hematology (n=153), immunology (n=78), intensive care unit (n=78) and thorax surgery (n=51). RESULTS: The median TPE procedure per patient was 4 (range, 1-50). All the procedures were performed on continuous flow cell separators and median plasma volume processed per cycle was 2471 ml (range 436-5000). The replacement fluids used were 3% hydroxyethylstarch (HES) (24%), 5% albumin (35%), fresh frozen plasma (25%), and HES and albumin (16%). HES was tolerated well even as a sole replacement fluid with acceptable minor side effects. In three patients with progressing hypoalbuminemia HES was replaced or combined with 5% albumin. Close monitoring of serum albumin and fibrinogen levels after repeated procedures is mandatory. CONCLUSION: In our four years of TPE experience we have increased our collaboration with other departments. 3% HES+/-5% Albumin is a feasible, well tolerated and cost effective replacement fluid combination especially for short-term plasma exchange therapy.  相似文献   
999.
It is well known that rifampicin can cause nephrotoxicity. Rifampicin-related pancreatitis and hyperthyroidism are rarely reported in the same patient in the presence of tubulointerstitial nephritis. Reported herein is the medical management of a patient with hemolytic anemia, acute renal failure, pancreatitis, and hyperthyroidism during with rifampicin therapy. A 50-year-old man was admitted to the hospital owing to abdominal colic and acute renal failure. He was treated with 2 courses of tetracycline-rifampicin for brucellosis 3 weeks and 4 months prior to admission. Physical examination showed blood pressure of 130/70 mm Hg, pulmonary crackles, and edema. Laboratory findings are detailed in the case report. Findings of abdominal ultrasonography suggested edematose pancreatitis and thyroid ultrasonography showed several solid nodules. Renal biopsy showed tubu-lointerstitial nephritis. Although rifampicin-related tubulointerstitial nephritis and acute renal failure are not uncommon during rifampicin therapy, the convergence of hyperthyroidism, pancreatitis, tubulointerstitial nephritis, and acute renal failure rarely presents in the same patient. Although pancreatitis, tubulointerstitial nephritis, and acute renal failure were ameliorated with corticoid therapy within 2 months, hyperthyroidism continued and required antithyroid therapy. In conclusion, rifampicin may trigger hyperthyroidism in patients with goiter.  相似文献   
1000.
Nonviral delivery of synthetic siRNAs in vivo   总被引:2,自引:2,他引:2       下载免费PDF全文
Sequence-specific gene silencing using small interfering RNA (siRNA) is a Nobel prize-winning technology that is now being evaluated in clinical trials as a potentially novel therapeutic strategy. This article provides an overview of the major pharmaceutical challenges facing siRNA therapeutics, focusing on the delivery strategies for synthetic siRNA duplexes in vivo, as this remains one of the most important issues to be resolved. This article also highlights the importance of understanding the genocompatibility/toxicogenomics of siRNA delivery reagents in terms of their impact on gene-silencing activity and specificity. Collectively, this information is essential for the selection of optimally acting siRNA delivery system combinations for the many proposed applications of RNA interference.  相似文献   
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