Wieske Luuk, Verhamme Camiel, Witteveen Esther, Bouwes Aline, Dettling-Ihnenfeldt Daniela S, van der Schaaf Marike, Schultz Marcus J, van Schaik Ivo N, Horn Janneke
Department of Intensive Care Medicine, Academic Medical Center, University of Amsterdam, Meibergdreef 9, room C3-311, PO box 22700, 1105 AZ, Amsterdam, The Netherlands,
Neurocrit Care. 2015 Jun;22(3):385-94. doi: 10.1007/s12028-014-0066-9.
An early diagnosis of ICU-acquired weakness (ICU-AW) is difficult because disorders of consciousness frequently preclude muscle strength assessment. In this study, we investigated feasibility and accuracy of electrophysiological recordings to diagnose ICU-AW early in non-awake critically ill patients.
Newly admitted patients, mechanically ventilated ≥2 days and unreactive to verbal stimuli, were included in this study. Electrophysiological recordings comprised nerve conduction studies (NCS) of three nerves and, if coagulation was normal, myography in three muscles. Upon awakening, strength was assessed (ICU-AW: average Medical Research Council score <4), blinded for electrophysiological recordings. Feasibility was expressed as the percentage of recordings that were both possible and had sufficient technical quality. Diagnostic accuracy of feasible (i.e., feasibility >75 %) recordings was analyzed based on cut-off values from healthy controls and from critically ill patients with and without ICU-AW.
Thirty-five patients were included (17 with ICU-AW). Recordings were obtained on day 4 (IQR: 3-6). Feasibility was acceptable for ulnar and peroneal nerve recordings, and low for sural recordings and myography. Diagnostic accuracy based on cut-off values from healthy controls was low. When using cut-off values from critically ill patients with and without ICU-AW, the peroneal compound muscle action potential amplitude and ulnar sensory nerve action potential amplitude had good diagnostic accuracy.
Nerve conduction studies of the ulnar and peroneal nerve are feasible in critically ill patients. The diagnostic accuracy is low using cut-off values from healthy controls. Cut-off values validated specifically for discrimination between critically ill patients with and without ICU-AW may improve diagnostic accuracy.
重症监护病房获得性肌无力（ICU-AW）的早期诊断较为困难，因为意识障碍常常妨碍肌力评估。在本研究中，我们调查了电生理记录在非清醒重症患者中早期诊断ICU-AW的可行性和准确性。
本研究纳入新入院、机械通气≥2天且对言语刺激无反应的患者。电生理记录包括三条神经的神经传导研究（NCS），如果凝血功能正常，还包括三块肌肉的肌电图检查。患者清醒后，评估肌力（ICU-AW：医学研究委员会平均评分<4），评估时对电生理记录结果保密。可行性以既可行且技术质量足够的记录所占百分比表示。基于健康对照以及有和没有ICU-AW的重症患者的临界值，分析可行（即可行性>75%）记录的诊断准确性。
纳入35例患者（17例患有ICU-AW）。在第4天（四分位间距：3-6天）进行记录。尺神经和腓总神经记录的可行性尚可，腓肠神经记录和肌电图检查的可行性较低。基于健康对照临界值的诊断准确性较低。当使用有和没有ICU-AW的重症患者的临界值时，腓总神经复合肌肉动作电位幅度和尺神经感觉神经动作电位幅度具有良好的诊断准确性。
尺神经和腓总神经的神经传导研究在重症患者中是可行的。使用健康对照的临界值时诊断准确性较低。专门针对区分有和没有ICU-AW的重症患者进行验证的临界值可能会提高诊断准确性。
