Herpertz Gerrit U, Focken Patrick, Radke Oliver
From the Department of Anaesthesiology, Intensive Care Medicine, Emergency Medicine and Pain Therapy, Klinikum Oldenburg (GUH), the Carl von Ossietzky Universität Oldenburg, School VI - School of Medicine and Health Sciences, Oldenburg (GUH), the Department of Anaesthesiology and Intensive Care Medicine, Klinikum Bremerhaven-Reinkenheide, Bremerhaven, Germany (PF, OR), the Department of Anaesthesiology, University Hospital of Dresden, Dresden, Germany (OR).
Eur J Anaesthesiol Intensive Care. 2025 May 21;4(3):e0074. doi: 10.1097/EA9.0000000000000074. eCollection 2025 Jun.
Ultrasound-guided measurement of the optic nerve sheath diameter (ONSD) is correlated with increased intracranial pressure (ICP). It has also been recognised as being useful in predicting intracranial hypertension, monitoring ICP and predicting outcome after resuscitation. The method has been described as easy to learn and with good inter-examiner reliability. But most studies were performed with only a few experienced examiners.
This study aimed to evaluate the learning progression and inter-examiner variability in point-of-care ultrasonographic assessment of the ONSD.
An observational cohort study.
Single tertiary centre in north-western Germany.
For the first part, we recruited a total of nine individuals naive to the ONSD measurement method. These were divided into two groups, one with and one without previous ultrasound experience. These individuals served as both examiners and 'volunteers' for each other during the learning phase of ONSD measurements. For the second part, two intubated and sedated intensive care patients had their ONSD measured by some of these newly trained examiners plus other more experienced examiners.
The examination was introduced following the Cognitive Apprenticeship method.
Learning progress was evaluated by time needed to perform the examination and by the decrease in the difference of the examination results to the mean ONSD of each individual. For the second part, examination results of the intensive care patients were used to calculate an interclass correlation coefficient.
The mean examination time decreased from 79 ± 48 to 48 ± 14 s from the first to the eight measurement, nearly following an exponential manner ( = 0.054). The deviation of the ONSD compared to the reference ONSD of each proband did not decrease exponentially over time in general. Examiners with ultrasound experience had a significantly lower variation (0.50 ± 0.17 vs. 0.74 ± 0.29 mm; = 0.012) regarding this particular point. The ICC calculated from results of measurement on the two patients was 0.832 (95% CI, 0.428 to 0.988).
According to our findings, the ultrasonographic assessment of the ONSD is easy to learn and expertise is gained quickly, especially for individuals with previous ultrasound experience. The data show good inter-examiner reliability on everyday patients.
Ethics Committee of the Medical Board of the State Bremen (No. 809/4).
超声引导下测量视神经鞘直径（ONSD）与颅内压（ICP）升高相关。它也被认为在预测颅内高压、监测ICP以及预测复苏后的预后方面很有用。该方法被描述为易于学习且检查者间可靠性良好。但大多数研究仅由少数经验丰富的检查者进行。
本研究旨在评估床旁超声评估ONSD的学习进程和检查者间变异性。
一项观察性队列研究。
德国西北部的单一三级中心。
在第一部分，我们共招募了9名对ONSD测量方法不熟悉的个体。他们被分为两组，一组有超声经验，一组没有。在ONSD测量的学习阶段，这些个体相互作为检查者和“志愿者”。在第二部分，两名插管并镇静的重症监护患者由一些新培训的检查者以及其他更有经验的检查者测量其ONSD。
按照认知学徒法进行检查介绍。
通过进行检查所需的时间以及检查结果与每个个体平均ONSD差值的减小来评估学习进程。在第二部分，使用重症监护患者的检查结果计算组内相关系数。
从第一次测量到第八次测量，平均检查时间从79± 48秒降至48± 14秒，几乎呈指数方式下降（=0.054）。总体而言，与每个受试者的参考ONSD相比，ONSD的偏差并未随时间呈指数下降。在这一特定方面，有超声经验的检查者变异显著更低（0.50± 0.17对0.74± 0.29毫米；=0.012）。根据对两名患者测量结果计算的组内相关系数为0.832（95%可信区间，0.428至0.988）。
根据我们的研究结果，超声评估ONSD易于学习，且能快速获得专业技能，尤其是对于有超声经验的个体。数据显示在日常患者中检查者间可靠性良好。
不来梅州医学委员会伦理委员会（编号809/4）
