[Aggressive treatment of deep vein thrombosis - contra]. / Aggressive Therapie der tiefen Venenthrombose - Kontra.

Together with the classical conservative treatment or the rarely necessary surgical thrombectomy in patients with acute deep vein thrombosis, catheter-directed thrombolysis is becoming more and more popular. This review provides a critical view on the evidence for catheter-directed thrombolysis providing a "Contra" position in contrast to the "Pro" position also published in this issue.

[Update carotid artery stenosis]. / Update Karotisstenose.

Stenosis of the extracranial carotid artery is a treatable cause of ischemic stroke and can reliably be detected and graded by vascular ultrasound. The differentiation between symptomatic and asymptomatic stenosis, the perioperative risk and the estimated life expectancy of the patient guide the therapy. Therapy is based on an optimal treatment of cardiovascular risk factors and antiplatelet drugs. Revascularization using surgical carotid endarterectomy is efficient for the prevention of stroke in patients with a high grade symptomatic stenosis. Endovascular therapy using stent-protected angioplasty of the carotid artery is an alternative in patients with a higher surgical risk with low complication rates when performed in experienced centres. Patients with asymptomatic carotid artery stenosis are primarily treated conservatively and revascularization is indicated in patients with a low surgical and global cardiovascular risk.

Hospitalization for vitamin-K-antagonist-related bleeding: treatment patterns and outcome.

BACKGROUND: Bleeding complications are common side effects of vitamin-K antagonist (VKA) therapy. Data on the in-hospital management and outcomes of these bleeding events are scarce and information is mostly derived from trial cohorts. OBJECTIVES: The objective was to collect data on the management and clinical outcome of hospitalizations owing to VKA-related bleeding in real-world practice. PATIENTS AND METHODS: We performed a multicenter observational cohort study involving 21 secondary and tertiary care hospitals in the administrative district Dresden, Saxony, Germany throughout the year 2005. All consenting patients presenting with VKA-related bleeding complications were included. No exclusion criteria applied. Data were collected at admission, at discharge and at 90 days to evaluate resource consumption, length of hospital stay and risk factors for in-hospital- and 3-month mortality. RESULTS: Two hundred and ninety patients were included (median age 74 years; 50.7% male). The main indications for VKA therapy were atrial fibrillation (63.4%), prior thromboembolism (18.6%) and mechanical heart valves (11.4%), and most common bleeding localizations were large hematoma (23.1%), upper gastrointestinal (GI) tract (17.9%) and intracranial bleeding (14.1%). On hospital admission, the median International Normalized Ratio (INR) was 3.0 (range 0.9-12.5, interquartile range [IQR] 2.1-3.9). In-hospital mortality was 7.6% with impaired renal function as the most relevant risk factor. At 90 days mortality was 14.1% and 15.3% of survivors were help-dependent. CONCLUSIONS: VKA-related bleeding leading to hospitalization is associated with long hospitalization, relevant resource utilization, high mortality or persistent sequlae. Patient-related factors such as impaired renal function, chronic cardiac or pulmonary disease and dementia are predictive of in-hospital and 3-month mortality.

Determinants of intermediate term clinical outcome after endovascular below-knee interventions.

BACKGROUND: To determine predictors of clinical outcome after endovascular interventions of crural arteries in patients with peripheral arterial disease. PATIENTS AND METHODS: We prospectively followed 154 limbs in 147 patients treated with below the knee endovascular interventions for critical limb ischemia (52 %) and severe claudication (48 %). Patient-immanent, hemodynamic-procedural and anatomic determinants of outcome were analyzed. Outcome was defined as event-free survival from the combined endpoint freedom from re-intervention, major amputation and death. RESULTS: Cumulative event-free survival after 12 months was 65.1 %. During follow-up 42 patients (27.3 %) required re-intervention, 8 (5.2 %) underwent major amputation and 5 (3.2 %) died. In univariate analyses, the presence of critical limb ischemia, multilevel disease, age > 72 years, impaired renal function, and long lesions (> 65 mm) were significant determinants of the study endpoint. The anatomic location of the lesion, distal patency of treated artery below the ankle, cardiovascular risk factors or concomitant cardiovascular diseases, and the type of postinterventional antithrombotic treatment did not influence outcome. CONCLUSIONS: Below-knee interventions resulted in acceptable procedural mid-term results and high rates of amputation free survival. Multilevel disease, long lesions and impaired renal function were indicative of a worse outcome.

Central adjudication of venous ultrasound in VTE screening trials: reasons for failure.

BACKGROUND: The accuracy of screening ultrasound for venous thrombosis in asymptomatic patients is still a matter of debate. The VENUS study evaluated the accuracy of centrally adjudicated venous ultrasound against venography in patients after major orthopedic surgery and found the sensitivity of ultrasound to be poor for both proximal and distal deep vein thrombus (DVT). OBJECTIVES: To evaluate whether thrombus characteristics such as location or size influence the diagnostic performance of centrally adjudicated venous ultrasound. METHODS: All false negative sonograms of the VENUS study were re-evaluated against the corresponding venograms. Discrepancies were categorized into types of diagnostic failures. Within these categories, thrombus characteristics such as location, length or size of thrombus were evaluated. RESULTS: One hundred and twelve pairs of discrepant ultrasound and venography documents were compared with 28 pairs with concordant results. Discrepancies were caused by local documentation failure (37.5%), failure of the ultrasound method (43.7%) and failure of the central adjudication process (18.7%). The overall size of thrombi was small, which caused about 40% of all sonographic failures with a detection threshold of five Marder points, a thrombus length of 9.5 cm and a number of 3.5 pathological compression manoeuvres. Proximal or distal location of DVT did not affect thrombus detection. CONCLUSION: If centrally adjudicated ultrasound is to be used in future VTE screening trials, training of local sonographers and central adjudicators needs to be intensified, because asymptomatic DVTs seem to be small and ultrasound sensitivity depends on the number of pathological compression manoeuvres documented in the ultrasound document. In contrast, distal or proximal thrombus location itself does not influence sensitivity.

Incidence, risk profile and morphological pattern of venous thromboembolism after prostate cancer surgery.

BACKGROUND: Venous thromboembolism (VTE) is the most common non-surgical complication after major pelvic surgery. Little is known about the risk factors or the time of development of postoperative venous thrombosis. METHODS: A cohort of 523 consecutive patients undergoing radical prostatectomy with lymphadenectomy was prospectively assessed by complete compression ultrasound at days -1, +8 and +21. RESULTS: Complete data were available in 415 patients, while four patients had VTE before surgery and were excluded from the analysis. In the remaining 411 patients, 71 VTE events were found in 69 patients (16.8%). Most were limited to calf muscle veins (56.5%), followed by deep calf vein thrombosis (23.2%), proximal deep vein thrombosis (DVT, 14.5%) and pulmonary embolism (PE, 5.8%). Of the 14 patients with proximal DVT/PE, 11 patients (78.6%) developed VTE between days 8 and 21. Risk factors for VTE were a personal history of VTE (OR 3.0), pelvic lymphoceles (LCs) impairing venous flow (OR 2.8) and necessity of more than two units of red blood cells (OR 2.6). CONCLUSION: Venous thromboembolism is common after radical prostatectomy. A significant proportion develops after day 8, suggesting that prolonged heparin prophylaxis should be considered. Since LCs with venous flow reduction result in higher rates of VTE, hemodynamically relevant lymphoceles should be surgically treated.

Ultrasound screening for asymptomatic deep vein thrombosis after major orthopaedic surgery: the VENUS study.

BACKGROUND: Venography is currently used to assess the incidence of deep vein thrombosis (DVT) in dose-finding and confirmatory trials of new antithrombotic agents. Centrally adjudicated, complete compression ultrasound (CCUS) could be a non-invasive alternative to venography. OBJECTIVES: A substudy of two, similarly designed, phase IIb trials of a novel, oral anticoagulant for the prevention of venous thromboembolism after elective hip or knee arthroplasty was undertaken to validate CCUS against venography. PATIENTS/METHODS: Patients received study drugs until mandatory, bilateral venography was performed 7 +/- 2 days after surgery. CCUS was performed within 24 h after venography by sonographers blinded to the venography result. Sonographers were trained and certified for the standardized examination and documentation procedure. Venograms and sonograms were adjudicated centrally at different sites by two independent readers; discrepancies between readers were resolved by consensus. RESULTS: A total of 1104 matching pairs of evaluable venograms and sonograms were obtained from the participants of the two trials (n = 1435): 19% of venograms and 20% of sonograms were not evaluable. The observed frequency of any DVT was 18.9% with venography and 11.5% with CCUS. Sensitivity of CCUS compared with venography was 31.1% for any DVT (95% confidence interval 23.4, 38.9), 21.0% (2.7, 39.4) for proximal DVT, and 30.8% (23.1, 38.6) for distal DVT. The figures for specificity were 93.0% (91.0, 95.1), 98.7% (98.0, 99.5), and 93.3% (91.5, 95.3), respectively. CONCLUSIONS: Based on these results, centrally adjudicated CCUS will be unable to replace venography for DVT screening early after major orthopaedic surgery in studies evaluating anticoagulant drugs.

[Bridging anticoagulation]. / Uberbrückende Antikoagulation.

Patients on anticoagulants of the vitamin K antagonist type may sometimes be scheduled for invasive procedures or surgical operations. In order to minimize the risk of thromboembolism caused by the interruption of chronic anticoagulation for the procedure, temporary administration of anticoagulants with shorter half-lives is required (so-called bridging anticoagulation). The present review outlines the spectrum of risks during this period regarding both thromboembolism and major bleeding. Low molecular weight heparins may be considered the medication of choice for bridging anticoagulation, mainly for practical reasons. Since they require no coagulation monitoring or dose adjustment, outpatient treatment is feasible. Such heparins are not labelled for the indication of bridging anticoagulation. However, based on recent studies of large patient cohorts, evidence of their efficacy and safety is significantly more solid than for unfractionated heparin. A simple dosing scheme for low molecular weight heparins is given here and all requirements are discussed for safe guidance through episodes of bridging anticoagulation.

Deep vein and isolated calf muscle vein thrombosis following long-haul flights: pilot study.

The risk of venous thromboembolism associated with long-haul flights is the subject of controversy. In a prospective, controlled study, we examined 160 passengers before and after return from a long-haul flight and 160 age-matched and sex-matched, non-travelling volunteers using venous compression ultrasound. Deep vein thrombosis was not observed in either group. Isolated calf muscle vein thrombosis (ICMVT) was present in 4/160 (2.5%) flight passengers and in 1/160 (0.6%) controls. All subjects with ICMVT were clinically asymptomatic, and ICMVT was located in the soleal muscle veins in all four subjects. Three of the four passengers with ICMVT had other risk factors for thrombosis.

Educational and career outcomes of an internal medicine preceptorship for first-year medical students.

OBJECTIVE: Medical educators have attempted in recent years to provide quality clinical experiences for medical students early in their medical training. We questioned whether participating in a preceptorship in internal medicine (PIM) resulted in better performances on subsequent clinical rotations and increased interest in internal medicine. PARTICIPANTS: Fifty-four students have participated in the PIM to date, with control groups consisting of students who applied for it but were not selected (n = 36), students participating in a preceptorship in family medicine (n = 168), and the remaining students (n = 330). DESIGN: Prospective cohort study. SETTING: University medical center and community practices. INTERVENTION: A 2-month, clinical preceptorship following the first year of medical school. MEASUREMENTS AND MAIN RESULTS: The following outcomes were assessed: scores in the introduction to clinical medicine course; grades in the medical ethics course; scores from the internal medicine clerkship; and choosing a career in internal medicine. In their second year, PIM students scored higher in both semesters of the introduction to clinical medicine course (87% and 86% vs 84% and 84%, p's <.01) and were more likely to receive honors in ethics (50% vs 29%, p <.01) than non-PIM students. During the internal medicine clerkship, PIM students' scores were significantly higher on an objective structured clinical examination (79% vs 76%, p =.05), ambulatory clinical evaluations (80% vs 76%, p <.01), and overall clerkship scores (78% vs 75%, p =.03) but not on inpatient clinical evaluations or on the National Board of Medical Examiners Subject Examination. Preceptorship students were more likely to receive honors grades in the medicine clerkship (33% vs 10%, p <.01), and they were more likely to match into internal medicine residencies than control students (54% vs 27%, p <.01). CONCLUSIONS: The PIM course is an intervention, early in students' careers, which appears to benefit them academically and increase their interest in internal medicine as a career.

Simulation methodology for estimating financial effects of telemedicine in West Virginia.

Understanding the full financial effects of telemedicine systems on payers, providers, and patients has been hampered by the lack of data from full-fidelity systems operating at a steady state. The vast majority of telemedicine systems in the United States have yet to achieve their full potential in serving their target populations and are operating well below capacity. The purposes of this research are two-fold: (1) to develop a methodology that compensates for the limited availability of empirical data on the financial effects of telemedicine; and (2) to test this methodology in a comprehensive telemedicine system in West Virginia. The proposed methodology utilizes simulation modeling techniques for evaluating the financial performance of a mature telemedicine system. It is particularly suitable for analyzing large, complex systems that have not yet achieved steady-state operation. Although complex, the methodology can be described simply as consisting of two major steps. The first is the identification of all of the relevant variables and parameters for modeling. The second consists of simulating "real world" decision situations involving all relevant variables and parameters. The relation among the variables and parameters are described in terms of mathematical equations. The ability of the researcher to estimate the financial effects of a given telemedicine system is a function of the extent to which the resulting model approximates conditions of the real world; i.e., the fit between model and reality.

Interpretive and procedural skills of the internal medicine clerkship: performance and supervision.

This descriptive study prospectively examined the performance and supervision of interpretive and procedural skills during an internal medicine clerkship. Students (N = 150) documented having done 7 required and 12 elective skills. Preceptors of required skills were interns (44%), residents (29%), attending physicians (12%), and others (16%). The elective procedures and the percentage of students doing them were as follows: skin tests, 78%; nasogastric tube insertion, 57%; paracentesis, 44%; bone marrow sampling, 35%; lumbar puncture, 34%; thoracentesis, 34%; Papanicolaou smear, 29%; central line placement, 27%; cardioversion, 13%; bladder catheter insertion, 11%; arthrocentesis, 9%; and skin biopsy, 7%. Elective procedures per student ranged from 0 to 9 (mean = 4) and were done less often in the first clerkship group than later in the academic year. Preceptors of electives were interns (46%), residents (39%), and attending physicians (9%). House staff were more likely and faculty less likely to precept electives than required procedures. Students' exposures to these skills are unequal. Their preceptor are generally house staff. To prepare medical students for postgraduate training, technical skills should be specifically addressed in the curriculum.

Creating an objective structured clinical examination for the internal medicine clerkship: pitfalls and benefits.

The objective-structured clinical examination (OSCE) is a useful tool in evaluating clinical competence. Traditional clinical-evaluation measures have been criticized as arbitrary and lacking reliability, whereas written exams test primarily cognitive aspects. The OSCE focuses on learner actions rather than abstract knowledge and evaluates in a uniform fashion. A 15-station OSCE was created for an internal medicine junior clerkship, based on predetermined skill and content goals. The exams then were scored by a single, blinded reviewer, again in a predetermined fashion. The OSCE has been studied in terms of reliability, content validity, and construct validity. The exam has become accepted by the department and has guided the continuing curricular development. The OSCE is not designed to measure all the domains of a learner's educational process. However, when used in conjunction with other evaluating mechanisms, it provides an objective outcome measure of the medical education process.

Smoke inhalation.

Two cases of smoke inhalation injury are reported with a brief review of the pertinent literature. The frequency of occurrence, the mortality rate, the clinical course of this common event are discussed with emphasis on the following facts: 1) Pulmonary injury is often associated with skin burns and, conversely, skin burns, particularly when severe, are accompanied by significant effects on pulmonary function; 2) Domestic fires, which account for most of these casualties, may involve complex exposure to a variety of aggressive agents (CO, HCN, NOx, etc.), causing systemic effects; 3) The clinical course of the most severe occurrences characteristically consists of three phases, namely acute pulmonary insufficiency, pulmonary edema and bronchopneumonia, in sequence; 4) The mortality rates of these clinical phases range at or about 50 per cent; 5) Significant laryngeal edema and even pulmonary edema may follow an interval of several hours, during which both subjective and objective evidence of injury may be minimal or unnoticed; and 6) The determination of carboxyhemoglobin levels often helps in gauging the severity of the exposure and related effects of either immediate or delayed appearance.