Background The most widely used classifications of adverse events (AE) in surgical neurology assign a grade to AE that depends on the therapy used to treat them or on new neurologic deficits. Both concepts have substantial shortcomings in grading AE severity. We present a novel multidimensional approach to this challenge and aim at validating the new grading system. Methods The new Therapy-Disability-Neurology (TDN) grading system classifies AE into five grades, depending on the associated therapy, disability, and neurologic deficits. We conducted a two-center study on 6071 interventions covering the whole neurosurgical spectrum with data prospectively recorded between January 2013 and September 2019 at the University Hospital Zurich (USZ) and at the Fondazione IRCCS Istituto Neurologico Carlo Besta (FINCB). Findings Using data from USZ, a positive correlation was found between the severity of AE and the length of hospital stay (LOS) as well as treatment cost. Each grade was associated with a greater deterioration of the Karnofsky Performance Status Scale (KPS) at discharge and at follow-up. Additionally, there was a correlation between the severity of AE and absolute KPS values. When using the same methods on an external validation cohort from FINCB, correlations between the grade of AE, LOS, and KPS at discharge were even more pronounced. Interpretation Our results suggest that the TDN grade is consistent with clinical and economic repercussions of AE and thus reflects AE severity. It is objective, practical, easily interpreted, and enables comparison between different medical centers. The TDN grade will constitute an important step forward towards a more precise and standardized documentation of AE and ultimately lead to a more critical and patient-centered appraisal of process and outcome measures in surgical neurology. Funding None.

中文翻译：

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外科神经病学中的不良事件：新型治疗-残疾-神经病学（TDN）级

背景技术手术神经病学中最广泛使用的不良事件（AE）分类对AE进行分级，这取决于用于治疗不良事件的疗法或新的神经功能缺损。两种概念在AE严重性分级中均存在重大缺陷。我们提出了一种新颖的多维方法来应对这一挑战，并旨在验证新的评分系统。方法新的疗法-残疾-神经病学（TDN）评分系统将AE分为五个等级，具体取决于相关的疗法，残疾和神经系统缺陷。我们对6071种干预措施进行了两个中心的研究，涵盖了整个神经外科手术领域，并在2013年1月至2019年9月之间在苏黎世大学医院（USZ）和IRCCS Istituto Neuroologico Carlo Besta基金会（FINCB）进行了前瞻性记录数据。调查结果使用来自USZ的数据，发现AE的严重程度与住院时间（LOS）以及治疗费用之间存在正相关。每个年级与出院时和随访时卡诺夫斯基绩效状态量表（KPS）的严重恶化有关。此外，AE的严重程度与绝对KPS值之间存在相关性。在FINCB的外部验证队列中使用相同的方法时，出院时AE，LOS和KPS等级之间的相关性更加明显。解释我们的结果表明TDN等级与AE的临床和经济影响一致，因此反映了AE的严重程度。它客观，实用，易于解释，并且可以在不同医疗中心之间进行比较。TDN等级将朝着更精确和标准化的AE记录迈出重要的一步，并最终导致对手术神经病学过程和结局指标进行更关键和以患者为中心的评估。资金无。