The issue of consent in medical practice

Following a recent court judgment, legal and moral issues surrounding consent have been thrown into the spotlight. Elizabeth Larner, Solicitor, and Rachel Carter, Partner, of Wollen Michelmore LLP, look at the issues surrounding consent, including where problems arise in the fields of clinical negligence and non‐accidental injury and what health care professionals can do to ensure that their advice to a patient about a procedure or treatment is sufficiently cogent and appropriately recorded so as to avoid later criticism and possible legal action. This annotation gives an overview of the legal principles surrounding consent in medical practice including informed consent, refusal of treatment and issues of capacity.     

A look at the various ratios in medicine – risk ratio,odds ratio and likelihood ratio

This article focuses on 3 kinds of ratios commonly used in biostatistics and research: risk ratio, odds ratio and likelihood ratio. It clarifies the meaning of risk and odds and then delves into the respective ratios.     

The usefulness of the likelihood ratio in the diagnosis of dyspepsia and gastroesophageal reflux disease

Clinicians are familiar with the concepts of sensitivity and specificity to describe the accuracy of a diagnostic test. These measures do not always express the probability that a patient has a disease with a given test result as this will vary with the prevalence of the disorder in the population. The likelihood ratio is a more clinically relevant method of reporting accuracy, and the probability of having a disease after a positive or negative test can be calculated. The likelihood ratio can be applied to the clinical problem of dyspepsia management. This suggests that Helicobacter pylori (H. pylori) test and treat will detect and treat most peptic ulcers with only 0.5% of H. pylori-negative patients having peptic ulcer disease. Serology is possibly acceptable in populations with an H. pylori prevalence of approximately 50%. The urea breath tests are more appropriate in more extreme prevalence ranges. Once the prevalence of H. pylori falls below 10%, then the urea breath test becomes inaccurate, and screening and treatment may be less appropriate. The absolute probability of having peptic ulcer disease in a largely H. pylori-negative population will be very small, however, and the appropriateness of performing any investigation in these circumstances is debatable. Finally, likelihood ratios indicate that the clinical diagnosis of gastroesophageal reflux disease (GERD) is not straightforward. Traditionally, it is believed that patients with dominant heartburn are likely to have GERD. Likelihood ratios predict, however, that patients with these symptoms have a little over 50% chance of having GERD as defined by 24-h esophageal pH studies.     

内科胸腔镜技术及其临床应用

内科胸腔镜（medicalthoracoscopy，又称Pleuroscopy）是一项侵入性操作技术，主要用于经无创方法不能确诊的胸腔积液患者的诊治。能够在直视下观察胸膜腔的变化并可进行胸膜壁层和（或）脏层活检，因此，这项技术的应用对肺及胸膜疾病的诊断具有重要的临床意义。     

从理论到实践推进医学模式的转变

西方恩格尔提出生物一心理社会医学模式已33年,至今模式转变推进迟缓。一是模式与医务人员实施模式的理论与能力缺乏的矛盾;二是人群中心身疾病的的比例及其程度与现有医疗卫生资源滞后的矛盾。恩格斯说：“不管自然科学家采取什么样的态度,他们还得受哲学的支配。”     

The clinical significance of cardiac troponins in medical practice

Troponins are regulatory proteins that form the cornerstone of muscle contraction. The amino acid sequences of cardiac troponins differentiate them from that of skeletal muscles, allowing for the development of monoclonal antibody-based assay of troponin I (TnI) and troponin T (TnT). Along with the patient history, physical examination and electrocardiography, the measurement of highly sensitive and specific cardiac troponin has supplanted the former gold standard biomarker (creatine kinase-MB) to detect myocardial damage and estimate the prognosis of patients with ischemic heart disease. The current guidelines for the diagnosis of non-ST segment elevation myocardial infarction are largely based on an elevated troponin level. The implementation of these new guidelines in clinical practice has led to a substantial increase in the frequency of myocardial infarction diagnosis.Automated assays using cardiac-specific monoclonal antibodies to cardiac TnI and TnT are commercially available. They play a major role in the evaluation of myocardial injury and prediction of cardiovascular outcome in cardiac and non-cardiac causes.In this review we discuss the clinical applications of cardiac troponins and the interpretation of elevated levels in the context of various clinical settings.