The impact of drug error reduction software on preventing harmful adverse drug events in England: a retrospective database study.

INTRODUCTION: The use of intravenous administration systems with dose error reduction software (DERS) is advocated to mitigate avoidable medication harm. No large-scale analysis of UK data has been attempted. This retrospective descriptive study aimed to estimate the prevalence of hard limit events and to estimate the potential severity of DERS events. METHOD: Twelve months of DERS data was obtained from two NHS trusts in England. Definitions for drug categories and clinical areas were standardised and an algorithm developed to extract hard maximum (HMX) events. Subject matter experts (SMEs) were asked to rate severity of all HMX events on a scale of 0 (no harm) to 10 (death). These were analysed by clinical area and drug category, per 1000 administrations. RESULTS: A total of 745 170 infusions were administered over 644 052 patient bed days (PBDs). 45% of these (338 263) were administered with DERS enabled. HMX event incidence across the whole dataset was 17.9/1000 administrations (95% CI 17.5 to 18.4); 9.4/1000 PBDs (95% CI 9.2 to 9.7). 6067 HMX events were identified. 4604 were <2-fold deviations and excluded. HMX were identified in all drug categories. The highest incidence was antibacterial drugs (2.21%; 95% CI 2.13 to 2.29). Of the 1415 HMX events reviewed by SMEs, 747 (52.6%) were low/no harm. Drugs with greatest potential harm were antiarrhythmics (21.8/1000 administrations; 95% CI 16.3 to 29.1), parenteral anticoagulants (24.16/1000 administrations; 95% CI 15.3 to 37.9) and antiepileptics (20.86/1000 administrations; 95% CI 16.4 to 26.5). DERS has prevented severe harm or death in 110 patients in these hospitals. Medical and paediatric areas had higher prevalence of potentially harmful HMX events, but these were probably related to profile design. CONCLUSION: Compliance with DERS in this study was 45%. DERS events are common, but potential harm is rare. DERS events are not related to specific clinical areas. There are some issues with definition and design of drug profiles that may cause DERS events, thus future work should focus on implementation and data standardisation for future large-scale analysis.

Developing Strategic Recommendations for Implementing Smart Pumps in Advanced Healthcare Systems to Improve Intravenous Medication Safety.

Avoidable harm associated with medication is a persistent problem in health systems and the use of preprogrammed infusion devices ('smart pumps') and data monitoring is seen as a core approach to mitigating and reducing the incidence of these harms. However, smart pumps are costly to procure, configure and maintain (in both human and financial terms) and are often poorly implemented. Variation in the manner in which medicines are prepared and used within complex modern healthcare systems exacerbates these challenges, and a strategic human-centred approach is needed to support their implementation. A symposium of 36 clinical and academic medication safety experts met virtually to discuss the current 'state of the art' and to propose strategic recommendations to support the implementation of medication administration technology to improve medication safety. The recommendations were that health systems (1) standardise infusion concentrations to facilitate the development of ready-to-administer formulations of frequently used medicines, and support 'out of the box' programming of infusion devices; (2) develop and implement drug libraries using human-centred approaches and the aforementioned standard concentrations, with a theoretical understanding of how devices are used in practice; (3) develop standardised metrics and outcomes to support the interpretation of data produced by infusion devices; (4) involve all stakeholders in the development of drug libraries and metrics to ensure broad understanding of the devices, their benefits and limitations; and (5) leverage input into device design, working with manufacturers and users. Using this strategic approach, it is then possible to envisage and plan real-world implementation studies using a uniform approach to quantify improvements in safety, efficiency and cost effectiveness.

Frailty Phenotype and Neuropsychological Test Performance: A Preliminary Analysis.

CONTEXT: Frailty is a common problem that affects adults older than 65 years. Correlations between the frailty phenotype and neuropsychological impairment have not been thoroughly researched. OBJECTIVE: To examine the association between frailty phenotype, neuropsychological screening test results, and neuropsychological domains known to characterize patients with mild cognitive impairment and dementia. METHODS: This retrospective medical record analysis consisted of ambulatory patients aged 65 years or older seen in an outpatient geriatric practice. All patients were assessed with the Montreal Cognitive Assessment (MoCA). A portion of those patients also underwent a comprehensive neuropsychological evaluation that assessed executive control, naming/lexical access, and declarative memory expressed as 3 neuropsychological index scores. Frailty phenotype was determined using criteria by Fried et al. RESULTS: Simple correlation found that lower MoCA test scores were associated with a higher level of frailty (r=-0.34, P<.032). Regression analyses found that greater frailty was associated with worse performance on tests that assessed executive control and working memory (backward digit span; r2=0.267; ß=-0.517; P<.011) and delayed recognition memory (r2=0.207; ß=-0.455; P<.025). CONCLUSION: A correlation was found between frailty and neuropsychological impairment, which suggests that frailty may be a potential indicator for the emergence of mild cognitive impairment and dementia.

Membrane capacitance measurements revisited: dependence of capacitance value on measurement method in nonisopotential neurons.

During growth or degeneration neuronal surface area can change dramatically. Measurements of membrane protein concentration, as in ion channel or ionic conductance density, are often normalized by membrane capacitance, which is proportional to the surface area, to express changes independently from cell surface variations. Several electrophysiological protocols are used to measure cell capacitance, all based on the assumption of membrane isopotentiality. Yet, most neurons violate this assumption because of their complex anatomical structure, raising the question of which protocol yields measurements that are closest to the actual total membrane capacitance. We measured the capacitance of identified neurons from crab stomatogastric ganglia using three different protocols: the current-clamp step, the voltage-clamp step, and the voltage-clamp ramp protocols. We observed that the current-clamp protocol produced significantly higher capacitance values than those of either voltage-clamp protocol. Computational models of various anatomical complexities suggest that the current-clamp protocol can yield accurate capacitance estimates. In contrast, the voltage-clamp protocol estimates rapidly deteriorate as isopotentiality is reduced. We provide a mathematical description of these results by analyzing a simple two-compartment model neuron to facilitate an intuitive understanding of these methods. Together, the experiments, modeling, and mathematical analysis indicate that accurate total membrane capacitance measurements cannot be obtained with voltage-clamp protocols in nonisopotential neurons. Furthermore, although current-clamp steps can theoretically yield accurate measurements, experimentalists should be aware of limitations imposed by step duration and numerical errors during fitting procedures to obtain the membrane time constant.