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1.

Background

Despite advances in prenatal repair, myelomeningocele (MMC) still produces devastating neurologic deficits. The amniotic membranes (AM) are a biologically active tissue that has been used anecdotally for human fetal MMC repair. This study evaluated the use of autologous AM compared to skin closure in an established fetal MMC model.

Methods

Seven fetal lambs underwent surgical creation of MMC at gestational age of 75 days followed by in utero repair at gestational age of 100 days. Lambs were repaired with an autologous AM patch followed by skin closure (n = 4) or skin closure alone (n = 3). Gross necropsy and histopathology of the spinal cords were performed at term to assess neuronal preservation at the lesion.

Results

An increase in preserved motor neurons and a larger area of spinal cord tissue were seen in AM-repaired lambs, as was decreased wound healing of the overlying skin. Loss of nearly all spinal cord tissue with limited motor neuron preservation was seen in skin only-repaired lambs.

Conclusions

AM-repaired lambs showed increased protection of spinal cord tissue compared to skin only-repaired lambs, but the overlying skin failed to close in AM-repaired lambs. These results suggest a potential role for AM in fetal MMC repair that warrants further study.  相似文献   
2.

Purpose

Antidepressant medications are commonly prescribed for the treatment of depression, anxiety, and chronic pain. Their use may lead to a number of side effects with important implications in the perioperative period. Our aim was to examine the effect of preoperative antidepressant administration on post-surgical hospital length of stay (LOS) in elective non-cardiac surgery patients.

Design

Historical cohort study.

Methods

Demographic and preoperative data were collected by chart review for all non-cardiac surgery patients who were assessed in the preoperative consult clinic from April 2008 through February 2009. Patients were grouped according to whether or not they were taking antidepressant medications. Median length of stay was compared between patients who took antidepressants preoperatively and those who did not.

Results

Data were collected for 3,692 patients. Two hundred eighty-nine (7.8%) patients were taking antidepressants preoperatively. Use of antidepressants was not associated with an increased hospital LOS. The median LOS was four days both for patients who took antidepressants preoperatively (95% confidence interval [CI] 4 to 4) and for those who did not (95% CI 3 to 5) (P = 0.13).

Conclusions

The preoperative use of antidepressant medications was not associated with increased postoperative hospital LOS following elective non-cardiac surgery.  相似文献   
3.

Purpose

Clonidine may help prevent cardiac complications in patients undergoing non-cardiac surgery and receiving chronic beta-blocker therapy. We conducted a multicentre pilot randomized trial to estimate recruitment rates for a full-scale trial and to assess the safety and tolerability of combining clonidine with chronic beta-blockade.

Methods

Patients who were at elevated perioperative cardiac risk, receiving chronic beta-blockade, and scheduled for major non-cardiac surgery were recruited in a blinded (participants, clinicians, outcome assessors) placebo-controlled randomized trial at three Canadian hospitals. Participants were randomized to clonidine (0.2 mg oral tablet one hour before surgery, plus 0.2 mg·day?1 transdermal patch placed one hour before surgery and removed four days after surgery or hospital discharge, whichever came first) or matching placebo. Feasibility was evaluated based on recruitment rates, with each centre being required to recruit 50 participants within 12-18 months. Additionally, we reviewed study drug withdrawals and safety outcomes, including clinically significant hypotension or bradycardia.

Results

Eighty-two of the 168 participants were randomized to receive clonidine and 86 to receive placebo. The average time to recruit 50 participants at each centre was 14.3 months. Six patients (7%) withdrew from clonidine, while four (5%) withdrew from placebo. Based on qualitative review, there were no major safety concerns related to clonidine. There was a moderate overall rate of cardiac morbidity, with 18 participants (11%) suffering postoperative myocardial infarction.

Conclusion

This pilot randomized trial confirmed the feasibility, safety, and tolerability of a full-scale trial of oral and transdermal clonidine for reducing the risk of cardiac complications during non-cardiac surgery. This trial was registered at www.clinicaltrials.gov: NCT00335582.  相似文献   
4.
This study used an axial transmission quantitative ultrasound (QUS) device to assess mandibular bone strength. The aim of the study was first to establish the precision and repeatability of the axial transmission QUS measurement for a range of mandibular anatomic sites, and second to investigate the ability of the modality to differentiate between osteoporotic subjects and a control group. Three groups of adult Caucasian women were recruited: (1) healthy premenopausal women (n?=?26), (2) healthy postmenopausal women (n?=?48), and (3) women with osteoporosis (n?=?53). Subjects were excluded from groups 1 and 2 if they had any pre-existing bone conditions. Speed of sound (SOS) measurements were taken from the mandible using an OmniSense multisite QUS device. Group 3 had dual-energy X-ray absorptiometry scans of the lumbar spine and femur. The most suitable site on the mandible was determined by repeat SOS measurements in 10 healthy premenopausal subjects, at 5 different sites. The parasymphysis site had the lowest root mean squared coefficient of variation at 0.74%, and was chosen as the most suitable site for mandibular SOS measurements. Group 1 and group 2 had significantly higher mean SOS measurements than the osteoporotic subjects (group 3), with means of 3683?m/s (210), 3514?m/s (221), and 3312?m/s (264), respectively. A 1-way analysis of variance confirmed a statistically significant difference between mean SOS measurements from the 3 groups (p?<?0.0001). Axial transmission QUS of the mandible can differentiate between subjects with osteoporosis and a healthy control group, and shows potential for use as a screening tool for osteoporosis.  相似文献   
5.

Background

Associations between intraoperative hypotension (IOH) and postoperative complications have been reported. We examined whether using different methods to model IOH affected the association with postoperative myocardial injury (POMI) and acute kidney injury (AKI).

Methods

This two-centre cohort study included 10 432 patients aged ≥50 yr undergoing non-cardiac surgery. Twelve different methods to statistically model IOH [representing presence, depth, duration, and area under the threshold (AUT)] were applied to examine the association with POMI and AKI using logistic regression analysis. To define IOH, eight predefined thresholds were chosen.

Results

The incidences of POMI and AKI were 14.9% and 14.8%, respectively. Different methods to model IOH yielded effect estimates differing in size and statistical significance. Methods with the highest odds were absolute maximum decrease in blood pressure (BP) and mean episode AUT, odds ratio (OR) 1.43 [99% confidence interval (CI): 1.15–1.77] and OR 1.69 (99% CI: 0.99–2.88), respectively, for the absolute mean arterial pressure 50 mm Hg threshold. After standardisation, the highest standardised ORs were obtained for depth-related methods, OR 1.12 (99% CI: 1.05–1.20) for absolute and relative maximum decrease in BP. No single method always yielded the highest effect estimate in every setting. However, methods with the highest effect estimates remained consistent across different BP types, thresholds, outcomes, and centres.

Conclusions

In studies on IOH, both the threshold to define hypotension and the method chosen to model IOH affects the association of IOH with outcome. This makes different studies on IOH less comparable and hampers clinical application of reported results.  相似文献   
6.
7.
BACKGROUND: Although the association between massive perioperative blood loss (MBL) and adverse outcomes is well recognized, it is unclear whether MBL is an independent risk factor or, instead, simply a marker for other adverse events or severity of illness. The objective of this cohort study was to quantify the independent association of MBL in cardiac surgery with all-cause in-hospital mortality. STUDY DESIGN AND METHODS: Data were prospectively collected on consecutive patients who underwent cardiac surgery with cardiopulmonary bypass at a quaternary-care academic center from 1999 to 2003. The number of red blood cell (RBC) units transfused within 1 day of surgery was used as a surrogate measure of perioperative blood loss. Receiver-operating characteristic curve analyses were employed to identify the most appropriate cutoff for defining MBL. The independent association of MBL with mortality was determined with multivariable logistic regression analyses. Bootstrapping and sensitivity analyses were used to confirm the validity of the results. RESULTS: MBL was defined as receiving at least 5 units of RBCs within 1 day of surgery. Of 9215 patients analyzed, 1.8 percent (n = 169) died and 9.7 percent (n = 890) had MBL. After adjusting for multiple potential confounders (including perioperative adverse events), MBL was associated with an 8.1-fold (95% confidence interval, 3.9-17.0) increase in the odds of death. This risk estimate was stable across different modeling conditions as well as in bootstrap sampling. CONCLUSION: MBL after cardiac surgery has a strong, independent association with in-hospital mortality.  相似文献   
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10.
Sir, The cutaneous eruption of glucagonoma is described as a distinctclinical entity, but in the early stages of this disease, clinicalsigns may be subtle. We present a patient who presented withpsoriasis and subsequently was diagnosed as having glucagonomasyndrome. A 40-year-old man presented in June 1998 with a year historyof an erythematous scaling seborrhoeic dermatosis, diagnosedclinically and histologically as  相似文献   
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