Learning from preventable deaths: exploring case record reviewers' narratives using change analysis

Objective

To determine if applying change analysis to the narrative reports made by reviewers of hospital deaths increases the utility of this information in the systematic analysis of patient harm.

Design

Qualitative analysis of causes and contributory factors underlying patient harm in 52 case narratives linked to preventable deaths derived from a retrospective case record review of 1000 deaths in acute National Health Service Trusts in 2009.

Participants

52 preventable hospital deaths.

Setting

England.

Main outcome measures

The nature of problems in care and contributory factors underlying avoidable deaths in hospital.

Results

The change analysis approach enabled explicit characterisation of multiple problems in care, both across the admission and also at the boundary between primary and secondary care, and illuminated how these problems accumulate to cause harm. It demonstrated links between problems and underlying contributory factors and highlighted other threats to quality of care such as standards of end of life management. The method was straightforward to apply to multiple records and achieved good inter-rater reliability.

Conclusion

Analysis of case narratives using change analysis provided a richer picture of healthcare-related harm than the traditional approach, unpacking the nature of the problems, particularly by delineating omissions from acts of commission, thus facilitating more tailored responses to patient harm.     

Maximal and explosive strength training elicit distinct neuromuscular adaptations, specific to the training stimulus

Purpose

To compare the effects of short-term maximal (MST) vs. explosive (EST) strength training on maximal and explosive force production, and assess the neural adaptations underpinning any training-specific functional changes.

Methods

Male participants completed either MST (n = 9) or EST (n = 10) for 4 weeks. In training participants were instructed to: contract as fast and hard as possible for ~1 s (EST); or contract progressively up to 75 % maximal voluntary force (MVF) and hold for 3 s (MST). Pre- and post-training measurements included recording MVF during maximal voluntary contractions and explosive force at 50-ms intervals from force onset during explosive contractions. Neuromuscular activation was assessed by recording EMG RMS amplitude, normalised to a maximal M-wave and averaged across the three superficial heads of the quadriceps, at MVF and between 0–50, 0–100 and 0–150 ms during the explosive contractions.

Results

Improvements in MVF were significantly greater (P < 0.001) following MST (+21 ± 12 %) than EST (+11 ± 7 %), which appeared due to a twofold greater increase in EMG at MVF following MST. In contrast, early phase explosive force (at 100 ms) increased following EST (+16 ± 14 %), but not MST, resulting in a time × group interaction effect (P = 0.03), which appeared due to a greater increase in EMG during the early phase (first 50 ms) of explosive contractions following EST (P = 0.052).

Conclusions

These results provide evidence for distinct neuromuscular adaptations after MST vs. EST that are specific to the training stimulus, and demonstrate the independent adaptability of maximal and explosive strength.     

B1 but not B2 bradykinin receptor agonists promote DU145 prostate cancer cell proliferation and migration

Background

The kallikrein-kinin system (KKS) is an endogenous pathway involved in angiogenesis and tumourigenesis, both vital for cancer growth and progression.

Objectives

To investigate the effect of two bradykinin receptor (B1R and B2R) agonists on growth and motility of prostate tumour (DU145) and micro-vascular endothelial cells (dMVECs).

Methods

Increasing concentrations of selective B1R and B2R agonists were added to cultured cells. Cell proliferation and migration were assessed using the 3-[4,5 dimethylthiazol-2-yl]-2,5-diphenyl-tetrazolium bromide (MTT) and modified Boyden Chamber assays, respectively. Where significant stimulation was found, the influence of an antagonist was also investigated.

Results

Neither growth nor motility of endothelial cells was affected by either agonist. In DU145 cells, while the B2R agonist was without any significant effect, the B1R agonist stimulated proliferation and migration at concentrations of 10nM and 50nM respectively. Further, this effect was abrogated when cells were pre-incubated with a B1R antagonist.

Conclusions

Unlike the physiologically-active B2R, the pathologically-inducible B1R may be implicated in prostate tumourigenic events. The involvement of the KKS in malignant prostate pathology supports on-going exploration of bradykinin receptor antagonists as target candidates in the development of alternate approaches to cancer therapy.     

Identification of Candida species in the clinical laboratory: a review of conventional,commercial, and molecular techniques

In healthy individuals, Candida species are considered commensal yeasts of the oral cavity. However, these microorganisms can also act as opportunist pathogens, particularly the so‐called non‐albicans Candida species that are increasingly recognized as important agents of human infection. Several surveys have documented increased rates of C. glabrata, C. tropicalis, C. guilliermondii, C. dubliniensis, C. parapsilosis, and C. krusei in local and systemic fungal infections. Some of these species are resistant to antifungal agents. Consequently, rapid and correct identification of species can play an important role in the management of candidiasis. Conventional methods for identification of Candida species are based on morphological and physiological attributes. However, accurate identification of all isolates from clinical samples is often complex and time‐consuming. Hence, several manual and automated rapid commercial systems for identifying these organisms have been developed, some of which may have significant sensitivity issues. To overcome these limitations, newer molecular typing techniques have been developed that allow accurate and rapid identification of Candida species. This study reviewed the current state of identification methods for yeasts, particularly Candida species.     

Bulimia nervosa: A population-based study of purgers versus nonpurgers

There has been recent interest in the possibility of dividing bulimia nervosa into two subtypes based on the method of weight prevention utilized by the individual. In an attempt to see if such a division is justified, this study compared 54 purging bulimics with 69 nonpurging bulimics ascertained from a population-based register of Virginia female twins. A bulimic was defined as a “purger” if she engaged in vomiting or laxative abuse. These two groups were examined on a variety of demographic, weight, and personality measures after controlling for the presence of obesity. No significant differences were found between the two groups on any of the variables examined. © 1993 by John Wiley & Sons, Inc.     

Long-term deaths from melanoma according to tumor thickness at diagnosis

There is little long-term follow-up information about how the number of melanoma deaths and case fatality vary over time according to the measured thickness of melanoma at diagnosis. This population-based longitudinal cohort study examines patterns and trends in case fatality among 44,531 people in Queensland (Australia) diagnosed with a single invasive melanoma (International Classification of Diseases for Oncology, third revision [ICD-O-3], C44, Morphology 872–879) between 1987 and 2011, including 11,883 diagnosed between 1987 and 1996, with up to 20 years follow-up (to December 2016). The 20-year case fatality increased by thickness, with the percentage of melanoma deaths within 20 years of diagnosis being up to 4.8% for melanomas with measured thickness <0.80 mm, 10.6% for tumors 0.8 to <1.0 mm and generally more than 30% for melanomas measuring 3 mm and more. For melanomas <1.0 mm, most deaths occurred between 5 and 20 years after diagnosis, whereas for thicker melanomas the reverse was true with most deaths occurring within the first 5 years. Five-year case fatality decreased over successive calendar time periods for melanomas <1.0 mm, but not for melanomas ≥1.0 mm. These findings demonstrate that the time course for fatal melanomas varies markedly according to tumor thickness at diagnosis. Improved understanding of the patient factors and characteristics of melanomas, in addition to tumor thickness, which increase the likelihood of progression, is needed to guide clinical diagnosis, communication with patients and ongoing surveillance pathways of patients with potentially fatal lesions.     

L-精氨酸对糖尿病大鼠心肌缺血再灌注损伤的影响

目的:观察糖尿病大鼠心肌缺血再灌注时血管紧张素Ⅱ、胰岛素样生长因子1、醛固酮、细胞间黏附分子1和自由基代谢的变化及L-精氨酸对其的影响。方法:实验于2005-02/2006-06在江苏大学医学院机能学实验室完成。①实验分组:腹腔注射链脲佐菌素制作糖尿病大鼠模型,30只大鼠造模成功。按随机数字表法分为3组(n=10):心肌缺血再灌注组:开胸结扎冠脉,造成心肌缺血,60min后放松再灌注60min;L-精氨酸治疗组:于手术前4周灌胃L-精氨酸250mg/(kg·d),然后重复心肌缺血再灌注组操作;假手术组:完成操作后只穿线不结扎,观察2h作为对照。实验结束时心室取血6mL,摘取心脏,留取左心室心肌组织。②实验评估:检测大鼠血浆血管紧张素Ⅱ、醛固酮和血清胰岛素样生长因子1含量及心肌细胞间黏附分子1蛋白表达。检测大鼠血清、心肌组织超氧化物歧化酶、谷胱甘肽-过氧化物酶活性、丙二醛含量及心肌线粒体Na ,K -ATP酶、Mg2 -ATP酶、Ca2 -ATP酶活性。结果:30只大鼠全部进入结果分析。①与假手术组相比,心肌缺血再灌注组血浆血管紧张素Ⅱ、醛固酮含量明显升高(P<0.05～0.01),血清胰岛素样生长因子1含量降低(P<0.05);L-精氨酸治疗4周后血浆血管紧张素Ⅱ、醛固酮含量低于心肌缺血再灌注组(P<0.05～0.01),血清胰岛素样生长因子1含量高于心肌缺血再灌注组(P<0.05)。②与假手术组相比,心肌缺血再灌注组血清、心肌丙二醛含量明显升高(P<0.05),血清、心肌超氧化物歧化酶和谷胱甘肽-过氧化物酶活性明显降低(P<0.05￣0.01);用L-精氨酸治疗4周后血清、心肌丙二醛含量低于心肌缺血再灌注组(P<0.05￣0.01),血清、心肌超氧化物歧化酶和谷胱甘肽-过氧化物酶活性高于心肌缺血再灌注组(P<0.05～0.01)。③与假手术组相比,心肌缺血再灌注组心肌线粒体Na ,K -ATP酶、Mg2 -ATP酶、Ca2 -ATP酶活性明显降低(P<0.05),心肌细胞间黏附分子1蛋白表达明显升高(P<0.01);用L-精氨酸治疗4周后心肌线粒体Na ,K -ATP酶、Mg2 -ATP酶、Ca2 -ATP酶活性明显高于心肌缺血再灌注组(P<0.05),心肌细胞间黏附分子1蛋白表达低于心肌缺血再灌注组(P<0.05)。结论:血管紧张素Ⅱ、醛固酮和胰岛素样生长因子1可能共同参与了糖尿病心肌缺血再灌注的发生,细胞间黏附分子1蛋白表达与糖尿病心肌损伤关系密切。L-精氨酸通过减少细胞间黏附分子1蛋白表达,起心肌保护作用。糖尿病心肌缺血再灌注时存在自由基代谢异常,补充L-精氨酸后,可通过提高超氧化物歧化酶、谷胱甘肽-过氧化物酶和ATP酶活性,降低丙二醛水平,减轻自由基损伤,改善心肌组织功能。     

四种中成药对气血双虚模型小鼠血象及免疫水平的影响

目的:为艾滋病抗病毒疗法所致的骨髓不良反应筛选疗效确切的中成药,观察分析参芪颗粒、复方阿胶浆、贞芪扶正颗粒、复方皂矾丸四种中成药对放血和注射环磷酰胺联合复制的气血双虚模型小鼠血象及免疫水平的影响。方法:实验于2005-08/09在河南中医学院药理实验室完成。①参芪颗粒(江西山高制药有限公司生产,批号040702);复方阿胶浆(山东东阿阿胶股份有限公司生产,批号050446);贞芪扶正颗粒(甘肃扶正药业科技股份有限公司生产,批号040803);复方皂矾丸(陕西郝其军制药有限责任公司生产,批号041014);当归补血口服液(郑州市协和制药厂生产,批号041122);环磷酰胺(上海华联制药有限公司生产,批号050101)。②选取清洁级昆明种小鼠150只,随机数字表法分为15组,10只/组:1～3组分别灌服参芪颗粒混悬液3,2,1g/kg;4～6组分别灌服复方阿胶浆30,20,10mL/kg;7～9组分别灌服贞芪扶正颗粒混悬液15,10,5g/kg;10～12组分别灌服复方皂矾丸混悬液2.4,1.6,0.8g/kg;第13组灌服当归补血口服液10g/kg;剩余2组为空白对照组和模型对照组,分别给于同体积生理盐水10g/kg。各组给药1次/d,连续给药10d。③除空白对照组外,其他各组从给药第1天开始建立气血双虚模型。每只鼠尾部放血0.25mL/10g,然后分别于第2,4,6,8天腹腔注射环磷酰胺80,40,40,40mg/kg。空白对照组同时间点仅腹腔注射等体积生理盐水。末次注射环磷酰胺后2h,眼眶取血,一部分用于血象测定,另一部分离心取血清,测定血细胞比容及血清中巨噬细胞集落刺激因子水平;解剖取胸腺和脾脏,检测胸腺皮质厚度、胸腺淋巴细胞数、脾小结大小、脾脏淋巴细胞数病理学指标的变化。结果:150只小鼠全部进入结果分析,放血和注射环磷酰胺并用可成功建立小鼠气血双虚模型。①与模型对照组比较,参芪颗粒3g/kg组、贞芪扶正颗粒10,5g/kg组、复方皂矾丸1.6g/kg组均可升高气血双虚模型小鼠白细胞水平(t=2.18～2.74,P<0.05),贞芪扶正颗粒15g/kg组作用更为显著(t=2.98,P<0.01);参芪颗粒1g/kg组、复方阿胶浆20mL/kg组、贞芪扶正颗粒15,10g/kg组均可升高红细胞水平(t=2.44～2.69,P<0.05),复方阿胶浆30mL/kg组、贞芪扶正颗粒5g/kg组、复方皂矾丸2.4,1.6g/kg组作用更为显著(t=2.91～3.66,P<0.01);当归补血口服液组、复方阿胶浆20mL/kg组、参芪颗粒3,1g/kg组、贞芪扶正颗粒15,10,5g/kg组均可升高血红蛋白水平(t=2.27～2.85,P<0.05),复方阿胶浆30mL/kg组、复方皂矾丸2.4,1.6g/kg组作用更为显著(t=3.07～4.04,P<0.01);当归补血口服液组、参芪颗粒3,2g/kg组均可升高血小板水平(t=2.20～2.41,P<0.05)。②与模型对照组比较,参芪颗粒2g/kg组、贞芪扶正颗粒5g/kg组均可升高气血双虚模型小鼠血细胞比容(t=2.01～2.62,P<0.05),参芪颗粒1g/kg组、复方阿胶浆30,20,10mL/kg组、贞芪扶正颗粒15,10,5g/kg组、复方皂矾丸2.4,1.6,0.8g/kg组作用更为显著(t=3.18～4.36,P<0.01);参芪颗粒2g/kg组、复方阿胶浆30,20,10mL/kg组、贞芪扶正颗粒15,10,5g/kg组、复方皂矾丸2.4,1.6g/kg组均可显著升高巨噬细胞集落刺激因子水平(t=3.60～6.80,P<0.01)。③与模型对照组比较,当归补血口服液组、参芪颗粒3,2,1g/kg组、复方阿胶浆30,20,10mL/kg组、贞芪扶正颗粒15,10,5g/kg组、复方皂矾丸2.4,1.6,0.8g/kg组均可显著增加气血双虚模型小鼠胸腺皮质厚度(t=3.71～9.34,P<0.01),增大脾小结(t=3.36～11.97,P<0.01),增加脾脏淋巴细胞数(t=4.29～10.44,P<0.01);复方阿胶浆30mL/kg组可明显增加小鼠胸腺淋巴细胞数(t=2.45,P<0.05),当归补血口服液组、参芪颗粒3,2,1g/kg组、复方阿胶浆20,10mL/kg组、贞芪扶正颗粒15,10,5g/kg组、复方皂矾丸2.4g/kg组作用更为显著(t=3.22～8.20,P<0.01)。结论:①四种中成药对气血双虚模型小鼠血红蛋白升高作用相近,以复方阿胶浆和贞芪扶正颗粒对白细胞和红细胞水平升高作用为强,以复方阿胶浆和贞芪扶正颗粒对血小板水平升高作用为优。②四种中成药对气血双虚模型小鼠血细胞比容的影响无差异,以贞芪扶正颗粒和复方皂矾丸对巨噬细胞集落刺激因子水平的升高作用为优。③以参芪颗粒、复方阿胶浆、贞芪扶正颗粒对胸腺皮质厚度和淋巴细胞数的促进作用为优,以参芪颗粒、贞芪扶正颗粒、复方皂矾丸对脾小结和脾脏淋巴细胞数的促进作用为优。