Assessment of patient capacity to consent to treatment

OBJECTIVE: To compare results of a specific capacity assessment administered by the treating clinician, and a Standardized Mini-Mental Status Examination (SMMSE), with the results of expert assessments of patient capacity to consent to treatment. DESIGN: Cross-sectional study with independent comparison to expert capacity assessments. SETTING: Inpatient medical wards at an academic secondary and tertiary referral hospital. PARTICIPANTS: One hundred consecutive inpatients facing a decision about a major medical treatment or an invasive medical procedure. Participants either were refusing treatment, or were accepting treatment but were not clearly capable according to the treating clinician. MEASUREMENTS AND MAIN RESULTS: The treating clinician (medical resident or student) conducted a specific capacity assessment on each participant, using a decisional aid called the Aid to Capacity Evaluation. A specific capacity assessment is a semistructured evaluation of the participant’s ability to understand relevant information and appreciate reasonably foreseeable consequences with regard to the specific treatment decision. Participants also received a SMMSE administered by a research nurse. Participants then had two independent expert assessments of capacity. If the two expert assessments disagreed, then an independent adjudication panel resolved the disagreement after reviewing videotapes of both expert assessments. Using the two expert assessments and the adjudication panel as the reference standard, we calculated areas under the receiver-operating characteristic curves and likelihood ratios. The areas under the receiver-operating characteristic curves were 0.90 for specific capacity assessment by treating clinician and 0.93 for SMMSE score (2p=.48). For the treating clinician’s specific capacity assessment, likelihood ratios for detecting incapacity were as follows: definitely incapable, 20 (95% confidence interval [CI] 3.6, 120); probably incapable, 6.1 (95% CI 2.6, 15); probably capable, 0.39 (95% CI 0.18, 0.81); and definitely capable, 0.05 (95% CI 0.01, 0.29). For the SMMSE, a score of 0 to 16 had a likelihood ratio of 15 (95% CI 5.3, 44), a score of 17 to 23 had a likelihood ratio of 0.68 (95% CI 0.35, 1.2), and a score of 24 to 30 had a likelihood ratio of 0.05 (95% CI 0.01, 0.26). CONCLUSIONS: Specific capacity assessments by the treating clinician and SMMSE scores agree closely with results of expert assessments of capacity. Clinicians can use these practical, flexible, and evaluated measures as the initial step in the assessment of patient capacity to consent to treatment. This project was supported by the physicians of Ontario through a grant (94–28) from Physicians’ Services Incorporated Foundation of Ontario. Dr. Naglie is partially supported by an Arthur Bond Fellowship from the Physicians’ Services Incorporated Foundation.     

Mechanisms of damage to corals exposed to sedimentation

We investigated the mechanisms leading to rapid death of corals when exposed to runoff and resuspended sediments, postulating that the killing was microbially mediated. Microsensor measurements were conducted in mesocosm experiments and in naturally accumulated sediment on corals. In organic-rich, but not in organic-poor sediment, pH and oxygen started to decrease as soon as the sediment accumulated on the coral. Organic-rich sediments caused tissue degradation within 1 d, whereas organic-poor sediments had no effect after 6 d. In the harmful organic-rich sediment, hydrogen sulfide concentrations were low initially but increased progressively because of the degradation of coral mucus and dead tissue. Dark incubations of corals showed that separate exposures to darkness, anoxia, and low pH did not cause mortality within 4 d. However, the combination of anoxia and low pH led to colony death within 24 h. When hydrogen sulfide was added after 12 h of anoxia and low pH, colonies died after an additional 3 h. We suggest that sedimentation kills corals through microbial processes triggered by the organic matter in the sediments, namely respiration and presumably fermentation and desulfurylation of products from tissue degradation. First, increased microbial respiration results in reduced O(2) and pH, initiating tissue degradation. Subsequently, the hydrogen sulfide formed by bacterial decomposition of coral tissue and mucus diffuses to the neighboring tissues, accelerating the spread of colony mortality. Our data suggest that the organic enrichment of coastal sediments is a key process in the degradation of coral reefs exposed to terrestrial runoff.     

欢迎国内外广大糖尿病相关医务工作者踊跃向本刊投稿

《中华糖尿病杂志》(ISSN 1674-5809.CN 11-5791/R)由中华医学会主办并编辑出版,是中国科技论文统计源期刊、中国科学引文数据库(CSCD)来源期刊月刊海期64面,国内外公开发行.2020年25元/期,全年共300元主要栏目包括:述评、专题笔谈、专家共识、论著、短篇论著、指南解读、综述、病例报告,现向广大医务工作者及科研人员征集文稿,内容涉及:糖尿病人群流行病学调查及危险因素评估.糖尿病新型诊断技术和综合治疗的新理论、新策略与预防措施,糖尿病急、慢性并发症及重症监护,糖尿病发病机制的病理生理及免疫学、分子遗传学研究,患者教育与护理,社区管理和卫生经济学分析.糖尿病与其他疾病的关系等.     

Barriers to the use of medications to treat alcoholism

In 1994, naltrexone became the first medication approved by the Food and Drug Administration as an adjunct in alcoholism treatment in almost fifty years. Despite evidence of its efficacy, use of naltrexone is not widespread. Patient and physician focus groups were used to identify reasons naltrexone has not been prescribed more widely. Barriers to its widespread use include a lack of awareness, a lack of evidence of efficacy in practice, side effects, time for patient management, a reluctance to take medications, medication addiction concerns, Alcoholics Anonymous (AA) philosophy, and price. The study indicates that medications to treat alcoholism must overcome numerous barriers before becoming widely accepted.     

Failure to induce resistance of Schistosoma japonicum to praziquantel

In order to explore the possible occurrence of inducing resistance of Schistosoma japonicum to praziquantel (PZQ), a set of animal experiments were carried out. Outbred mice (NIH strain), Anhui isolates of S. japonicum and Oncomelania hupensis were used. In one protocol five weeks after being infected with 48-52 cercariae, mice were orally dosed with PZQ 300 mg/kg, and killed 82 days later to isolate eggs from the liver. Snails were exposed to miracidia released from egg-hatching. F1 progeny were thus obtained through cercarial inoculation. The same scheme was applied for the establishment of the F2 generation. In another protocol two weeks after infection, PZQ 50 mg/kg/day was given to mice for 5 days. Eggs were collected 26-27 days post treatment and the identical procedures were adopted for F1 and F2 generations successively. Analysis of total worm and female worm reduction rates indicated that there was no significant difference between the sensitivity to PZQ of F1 and F2 progenies of S. japonicum and the parent worms.     

不同HBV基因型感染慢性乙型肝炎患者对核苷(酸)类药物治疗的应答反应比较

目的研究与探讨HBV基因型与慢性乙型肝炎患者肝组织病理学变化及对核苷(酸)类抗病毒药物疗效的关系。方法随机将慢性HBV感染者541例分为4组:拉米夫定组136例、替比夫定组135例、恩替卡韦组135例和阿德福韦组135例,各治疗48周。治疗前应用聚合酶链反应法确定HBV基因型,并于治疗前和治疗48周时分别检测肝功能、HBV DNA和HBV M。其中109例行肝组织病理学检查。结果本组HBV B基因型94例(17.38%),C型410例(75.79%),B/C混合型37例(6.84%),未检出其他基因型;在B型感染者,肝组织G3占37.3%、S313.0%,C型感染者G3占8.7%、S3占22.7%,B基因型与C基因型之间比较,有统计学意义(P<0.05);在拉米夫定、恩替卡韦和替比夫定治疗患者,B型、C型和B/C混合型之间疗效的比较,有统计学差异(P<0.05),而在阿德福韦酯治疗患者,几种不同的基因型感染患者疗效无统计学差异(P>0.05)。结论 HBV基因型与患者肝组织病理学改变及对核苷类抗病毒治疗的疗效密切相关。     

辩证看待CAI在寄生虫学教学中的应用

现代化的计算机辅助教学(CAI)在寄生虫学教学中具有生动直观、突破难点、激发学生兴趣、信息量大等优势,同时也存在一些不足,应辩证地看待CAI。CAI不可能替代传统教学,应与传统教学相结合,使之优势互补,并通过提高课件质量,加强对青年教师的培训提高寄生虫学教学效果。