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1.

Background

In the emergency department, rib fractures are a common finding in patients who sustain chest trauma. Rib fractures may be a sign of significant, underlying pathology, especially in the elderly patients where rib fractures are associated with significant morbidity and mortality. To date, no studies have evaluated the ability of ultrasound to detect rib fractures using cadaver models and subsequently use this model as a teaching tool.

Objectives

The purpose of this study was to determine if it is possible to generate rib fractures on cadaver models which could be accurately identified using ultrasound.

Methods

This was a cross-sectional study performed during one session at a cadaver lab. A single hemithorax from four adult cadavers were used as models. Single rib fractures on each of rib five through eight were created. Four subjects, blinded to the normal versus fractured ribs, were asked to identify the presence of a fracture on each rib.

Results

A total of 8 of 16 potential ribs had fractured induced by study staff. Mean accuracy was 55% for all subjects. The overall sensitivity and specificity for detecting rib fractures was 50% (CI: 31.89–68.11) and 59.38% (CI: 35.69–73.55) respectively. The overall PPV and NPV was 55.17% and 54.29% respectively.

Conclusions

In this pilot study, subjects were not able to detect induced rib fractures using ultrasound on cadaver models. The use of this model as a teaching tool in the detection of rib fractures requires further investigation.  相似文献   
2.
Hepatitis is a rare complication of herpes simplex virus (HSV), often leading to acute liver failure (ALF), liver transplantation (LT), and/or death. Our aim was to identify variables associated with either survival or progression (death/LT), based on an analysis of cases in the literature and our institution. A total of 137 cases (132 literature, 5 institutional) of HSV hepatitis were identified. The main features at clinical presentation were fever (98%), coagulopathy (84%), and encephalopathy (80%). Rash was seen in less than half of patients. Most cases (58%) were first diagnosed at autopsy and the diagnosis was suspected clinically prior to tissue confirmation in only 23%. Overall, 74% of cases progressed to death or LT, with 51% in acyclovir-treated patients as compared to 88% in the untreated subjects (P=0.03). Variables on presentation associated with death or need for LT compared to spontaneous survival: male gender, age>40 yr, immunocompromised state, ALT>5,000 U/L, platelet count<75x10(3)/L, coagulopathy, encephalopathy, and absence of antiviral therapy. In conclusion, HSV hepatitis has a high mortality and is often clinically unsuspected. Patients who are male, older, immunocompromised, and/or presenting with significant liver dysfunction are more likely to progress to death and should thus be evaluated for LT early. Based on the frequent delay in HSV diagnosis, low risk-benefit ratio, and significantly improved outcomes, empiric acyclovir therapy for patients presenting with ALF of unknown etiology is recommended until HSV hepatitis is excluded.  相似文献   
3.
This paper documents the type, frequency and duration of complications associated with regional anaesthesia of the maxillary nerve via the greater palatine canal in a series of 101 patients treated in the Oral Surgery Department, United Dental Hospital of Sydney.  相似文献   
4.
In these studies, the physical dependence liability of butorphanol, a mixed 'agonist/antagonist' opioid analgesic, was compared to that of morphine. Male, Sprague-Dawley rats received i.c.v. infusions of saline (1 microliter/h), or an equimolar dose of butorphanol or morphine (52.3 nmol/h) for 3 days. The physical dependence liabilities of these two compounds were then compared by assessing both behavioral withdrawal signs and weight loss following naloxone-precipitated withdrawal. Body weight loss was also evaluated following abrupt (cessation of infusion) withdrawal from butorphanol or morphine. In animals receiving i.c.v. infusions of butorphanol or morphine, naloxone administration (5 mg/kg s.c.) induced an equivalent degree of body weight loss compared to saline-treated animals. In addition, the ED50 of naloxone to produce wet shakes, escape behavior, teeth chattering, urination and defecation was equivalent in rats receiving butorphanol or morphine. Infusions of butorphanol or morphine also produced an equivalent degree of weight loss in animals undergoing abrupt withdrawal. These results demonstrate then that a substantial degree of physical dependence had developed in rats which received a large dose of butorphanol.  相似文献   
5.
BACKGROUND AND OBJECTIVE: The complications of 25-gauge transconjunctival sutureless vitrectomy based on the surgical indications were reviewed. PATIENTS AND METHODS: Thirty-eight patients underwent 25-gauge transconjunctival sutureless vitrectomy. Indications for vitrectomy, preoperative and postoperative best-corrected visual acuity, preoperative and postoperative intraocular pressure, and any intraoperative or postoperative complications were recorded. RESULTS: Complications included the need to suture a leaking sclerotomy intraoperatively in four eyes (9%), all of which involved oil removal; postoperative hypotony with choroidals in two eyes (5%); mild progression of nuclear sclerotic cataract in one eye (2% of all eyes, 4% of phakic eyes); the need to switch to 20-gauge pars plana vitrectomy in one eye (2%); corneal abrasion in one eye (2%); and retinal detachment in one eye (2%). Sclerotomy leakage and hyopotony with choroidals were only encountered in cases involving previously vitrectomized eyes, whereas none of the eyes without previous vitrectomy had leakage-related complications. CONCLUSIONS: Previously vitrectomized eyes have a higher incidence of complications related to postoperative leakage, possibly due to the lack of plugging effect of peripheral vitreous on the unsutured sclerotomy. One should consider suturing any leaking sclerotomy at the conclusion of surgery involving previously vitrectomized eyes.  相似文献   
6.
Anthracycline cardiotoxicity.   总被引:3,自引:0,他引:3  
Anthracycline drugs have been widely used as chemotherapeuticagents against a range of cancers, including sarcomas, carcinomas,leukaemias, and lymphomas. However, cardiotoxic effects, inparticular the development of cardiomyopathy, have limited theirclinical use. The observation of dose-dependent cardiotoxicityhas resulted in a recommended empirical dose limit of 450 mg/m2of body surface area. Age, gender, pre-existing heart disease,hypertension, and mediastinal irradiation have also been implicatedas factors contributing to the development of doxorubicin-associatedcardiomyopathy. However, cardiotoxicity may still occur at relativelylow levels of drug administration, even in individuals withno additional risk factors, and the onset may be delayed bymany years.1 More recently, the use of trastuzumab, a monoclonalantibody directed against the HER2 receptor, has been  相似文献   
7.
We report a unique case of coexistingexogenous lipoid pneumonia, endogenous lipoid pneumonia (EU), and pulmonary alveolar proteinosis (PAP) in a 5-year-old patient with severe neurodevelop mental disease. The patient presented with gastroesophageal reflux and presumed chronic lung disease resulting from recurrent aspiration pneumonias and succumbed to respiratory failure. The autopsy showed lipid-laden macrophages and periodic acid-SchiJf9ositive granular matm'al i n alveolar spaces and multilamellated structures within both alveolar macrophages and extracellular debris.

These findings were similar to those in previous reports of coexisting E I P and PAP in the setting of gastroesophageal refux [I] . However, the present case diJfered by the presence of scattered large osmiophilic extracellular lipid vacuob. Besides strengthening the association between EIP and PAP and their relationship to gastroesophageal refux, this case suggests that t h q may arise together with exogenous lipoid pneumonia, through related mechanisms, in the setting of neurodevelopmental disease.  相似文献   
8.
OBJECTIVE: Depression after hip fracture surgery is prevalent and associated with increased mortality rates and impaired functional recovery. The incidence of new-onset depressive symptoms in patients initially not depressed after hip fracture surgery and their relationship with functional recovery is unknown. METHODS: A cohort of 139 nondepressed elderly patients (>60 years) hospitalized for hip fracture surgery were followed up for six months. Clinically significant depressive symptoms were defined as a score of 7 or more on the 15-item Geriatric Depression Scale. RESULTS: The authors found a cumulative incidence rate of 20.5% adjusted for dropouts. Multiple Cox-regression analyses yielded the presence of subthreshold symptoms of depression, anxiety, pain, and cognitive impairment at baseline, the premorbid level of mobility, and a history of (treated) depression as risk factors for incident depression (p <0.05). A forward, conditional procedure identified postoperative pain (hazard ratio [HR] = 1.32, 95% confidence interval [CI]: 1.14-1.53, Wald chi(2) = 13.57, df = 1, p <0.001) and baseline anxiety (HR = 1.25, 95% CI: 1.08-1.44, Wald chi(2) = 8.86, df = 1, p = 0.003) as the strongest independent risk factors. Incident depression was associated with a less favorable outcome at 3 months follow-up. CONCLUSION: This exploratory study identified two treatable baseline characteristics that predicted incident depression in nondepressed patients after hip-fracture surgery.  相似文献   
9.
BACKGROUND: Research has sought to understand how environmental factors influence adolescent physical activity, yet little is known about where and with whom adolescents are physically active. PURPOSE: This study used electronic ecological momentary assessment (e.EMA) to map the social and physical contexts of exercise and walking across adolescence. Differences in physical activity contexts by gender, grade in school, day of the week, and season were examined. METHODS: Twice a year between 9th and 12th grade, 502 adolescents (51% female) of mixed ethnicity (55% White) participated in 4-day e.EMA intervals (Thursday-Sunday) where their primary activity (e.g., exercise, TV, homework), social company (e.g., friends, family, class), and physical location (e.g., home, school, outdoors) were assessed every 30 (+/-10) min during waking hours. RESULTS: Overall, greater proportions of exercise and walking were reported with friends, outdoors, and at school. However, boys were more likely to report exercising and walking in outdoor locations than girls. Exercising with classmates, family, and at school decreased across high school. Walking with family, friends, and outdoors also decreased. On weekdays compared to weekends, students reported a greater proportion of their exercise and walking at school. Students were more likely to report exercising and walking outdoors in the fall and the spring than in the winter. CONCLUSION: e.EMA showed that the social and physical contexts of adolescent exercise and walking vary as a function of gender, grade in school, day of the week, and season. Understanding the contexts of physical activity during the high school years can be helpful in designing interventions during adolescence.  相似文献   
10.
Hypertension and atherosclerosis make independent contributions to the pathogenesis of cardiovascular disease. Diuretics and beta adrenergic blockers, effective antihypertensive medications, exhibit some untoward effects on lipid metabolism, while most other antihypertensive medications tend not to exhibit such effects. In animal models, beta adrenergic blockers, angiotensin converting enzyme (ACE) inhibitors, and calcium antagonists have anti-atherogenic effects. A vascular biological approach to therapy for the patient with both hypertension and atherosclerosis is recommended. This includes effective reduction of blood pressure--preferably with agents that do not adversely affect lipid metabolism--and treatment of lipid metabolism disorders.  相似文献   
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