Simulation model of renal replacement therapy: predicting future demand in England.

BACKGROUND: The demand for renal replacement therapy (RRT) in England has risen steadily, although from a lower base than many other developed countries. Predicting the future demand for RRT and the impact of factors such as the acceptance rate, transplant supply and patient survival, is required in order to inform the planning of such services. METHODS: A discrete event simulation model estimates the future demand for RRT in England in 2010 for a range of scenarios. The model uses current prevalence and current and projected future acceptance rates, survival rates and the transitions between modalities to predict future patient numbers. National population and mortality data, published literature and data from the UK Renal Registry and UK Transplant, are used to estimate unmet need for RRT, the impact of changing demography and incidence of Type 2 diabetes, patient haemodialysis (HD) survival and transplant supply. RESULTS: By 2010 the predicted prevalence will have increased from about 30,000 in 2000 to between 42 and 51,000 (900-1000 p.m.p.), an average annual growth of 4.5-6%. Changing transplant supply has a small effect on overall numbers but changes the proportion of patients with functioning graft by up to 8%. Even with an optimistic increase in transplant supply (11% p.a. for 5 years), numbers on HD will continue to rise substantially, especially in the elderly. The factors most influencing future patient numbers are the acceptance rate and dialysis survival. CONCLUSION: This model predicts a substantial growth in the RRT population to 2010 to a rate approaching 1000 p.m.p., particularly in the elderly and those on HD, with a steady state not being reached for at least 25 years.     

Clinical parameters that predict histology of postchemotherapy retroperitoneal lymph node mass in testicular cancer

BACKGROUND: Since the advent of cisplatin-based chemotherapy, the majority of metastatic testicular cancers can be cured by chemotherapy followed by retroperitoneal lymph node dissection (RPLND). However, postchemotherapy RPLND confers no therapeutic benefit if the residual mass contains no viable cells. Therefore, to determine which parameters predict a patient's likelihood of having only necrosis in the residual mass, we retrospectively analyzed clinical parameters of patients who underwent postchemotherapy RPLND. METHODS: Data from 27 patients with metastatic testicular cancer were analyzed. The histology of the primary tumor was seminoma in 11 cases and non-seminoma in 16 cases. All of the patients with non-seminoma showed a normalization of tumor markers after chemotherapy. Analysis of clinical parameters included data for the initial histology, pretreatment tumor marker levels, postchemotherapy retroperitoneal mass size, and the histology of the dissected RPLNs. RESULTS: Histological examination of dissected RPLNs showed residual tumor in 27% of seminoma patients and 38% of non-seminoma patients. In seminoma patients, no viable cells were found in all six patients with pretreatment lactate dehydrogenase (LDH) levels below 7.5 times the upper limit of normal, or in all five of the patients with postchemotherapy RPLNs less than 2.5 cm. In non-seminoma patients, no viable cells were found in nine of 10 patients with pretreatment alpha-fetoprotein (AFP) levels less than 2700 ng/mL, or in eight of nine patients with residual mass less than 2.5 cm. CONCLUSIONS: Both postchemotherapy RPLN mass size and pretreatment tumor marker levels are possible predictors for necrosis of the residual mass in testicular cancer patients.     

Autonomy and modernisation: the management of change in an English primary care trust

Recent New Labour policy for the ‘modernisation’ of Government places a good deal of emphasis on decentralisation. This emphasis is particularly marked in relation to the organisation of primary care. However, like hospitals and other National Health Service institutions, primary care trusts (PCTs) are subject to a substantial raft of centrally established performance targets and indicators, including those which contribute to the public award of between zero and three performance ‘stars’. This raises questions about the extent to which employees can exercise autonomy in the context of rigid top‐down directives. This paper presents findings from a study using participant observation and interviews to examine the impact of a training course aimed ostensibly at increasing employee autonomy in an English PCT. The suggestion is that attempts to make employees more autonomous can be seen as a strategy for increasing central control based upon the internalisation by the employees of centrally promulgated values. The attraction of such strategies is that they may be potentially more effective and less costly than alternative strategies of direct control. However, the study suggests that the outcome of attempts by such methods as programmes to increase employee autonomy may be very different from those intended.     

Asystole Following Left Ventricular Pacing

During biventricular ICD implantation, pacing the epicardial inferior posterior-lateral surface of the left ventricle via the coronary sinus produced asystole. The proposed mechanism is a Bezold-Jarisch reflex manifested by a drop in heart rate and blood pressure through direct C fiber stimulation. (PACE 2004; 27[Pt. I]:815–817)     

The Usefulness of Magnetic Resonance Imaging in the Diagnosis of Anterolateral Impingement of the Ankle

The purpose of this study is to assess the sensitivity and specificity of magnetic resonance imaging (MRI) in the diagnosis of anterolateral impingement of the ankle and to assess the most helpful sequence in making the diagnosis. Twenty-four patients who had undergone ankle arthroscopy were chosen. Twelve patients had arthroscopically documented anterolateral impingement, and 12 patients with no impingement on arthroscopy served as controls. Two musculoskeletal radiologists and an orthopedic surgeon, blinded to the operative diagnosis, retrospectively reviewed selective MRI images in the sagittal, axial, and coronal planes. The sensitivities and specificities were calculated for all 3 reviewers. The Kendall coefficient of concordance was calculated for overall agreement among reviewers. Sensitivities varied from 0.75 to 0.83, whereas specificities varied from 0.75 to 1.00. Using the Fisher exact test of contingency, the sensitivities and specificities showed that all reviewers' interpretations were statistically significant with P = .039, .001, and .012, respectively. The axial images were felt to be most helpful in making the diagnosis. The physicians felt that the sagittal images were helpful in 67%, 83%, and 100%, respectively. MRI is a useful tool that can aid the clinician in the diagnosis of anterolateral impingement of the ankle. T1 sagittal images demonstrating displacement of the normal fat signal anterior to the fibula by scar can be useful and help to confirm the diagnosis.     

不同临床和病理分型对肝门部胆管癌切除术预后的影响

目的 研究临床和病理分型与肝门部胆管癌切除术疗效的关系。方法总结1993年至2004年在解放军总医院肝胆外科手术切除的肝门部胆管癌198例病例资料。结果临床分型Ⅰ型34例，Ⅱ型60例，Ⅲa型27例，Ⅲb型33例，Ⅳ型19例，Ⅴa型6例。Ⅴb型19例。病理高分化腺癌35例，中分化腺癌52例，低分化腺癌54例，三者的中位生存期分别为29．5、11、5．5个月；病理切缘阴性者与切缘阳性者生存率有显著性差异（P 〈0．05）。手术并发症出现率41．4％，围手术期死亡1例。结论肝门部胆管癌根据临床分型进行相应的手术治疗；病理切缘阴性是影响预后的主要因素之一；围手术期正确处理，是减少手术并发症，提高患者生活质量和延长生存期的关键。     

Pharmacologic management of overactive bladder

Overactive bladder (OAB) is a prevalent and costly condition that can affect any age group. Typical symptoms include urinary urgency, frequency, incontinence and nocturia. OAB occurs as a result of abnormal contractions of the bladder detrusor muscle caused by the stimulation of certain muscarinic receptors. Therefore, antimuscarinic agents have long been considered the mainstay of pharmacologic treatment for OAB. Currently, there are five such agents approved for the management of OAB in the United States: oxybutynin, tolterodine, trospium, solifenacin and darifenacin. This article summarizes the efficacy, contraindications, precautions, dosing and common side effects of these agents. All available clinical trials on trospium, solifenacin and darifenacin were reviewed to determine its place in therapy.     

Guidelines for Trials of Behavioral Treatments for Recurrent Headache, First Edition: American Headache Society Behavioral Clinical Trials Workgroup

Guidelines for design of clinical trials evaluating behavioral headache treatments were developed to facilitate production of quality research evaluating behavioral therapies for management of primary headache disorders. These guidelines were produced by a Workgroup of headache researchers under auspices of the American Headache Society. The guidelines are complementary to and modeled after guidelines for pharmacological trials published by the International Headache Society, but they address methodologic considerations unique to behavioral and other nonpharmacological treatments. Explicit guidelines for evaluating behavioral headache therapies are needed as the optimal methodology for behavioral (and other nonpharmacologic) trials necessarily differs from the preferred methodology for drug trials. In addition, trials comparing and integrating drug and behavioral therapies present methodological challenges not addressed by guidelines for pharmacologic research. These guidelines address patient selection, trial design for behavioral treatments and for comparisons across multiple treatment modalities (eg, behavioral vs pharmacologic), evaluation of results, and research ethics. Although developed specifically for behavioral therapies, the guidelines may apply to the design of clinical trials evaluating many forms of nonpharmacologic therapies for headache.