Diagnostic accuracy of Early ulTrasound measurement coupled with neuromuscular EleCTrical stimulation for diagnosing ICU-acquired weakness: an observational study (DETECT)

<bold>Background:</bold> Early identification of patients at risk of ICU-acquired weakness (ICU-Aw) is challenging but could prevent its occurrence and its consequences. <bold>Objectives:</bold> Assessing if quadriceps thickening and stiffening during neuromuscular electrical stimulation (NMES) accurately identify ICU-Aw at awakening. <bold>Methods:</bold> Critically ill patients under mechanical ventilation (MV) for at least 24 hours were eligible. NMES was applied to the quadriceps muscle, recording intensity for visible contraction. Ultrasound and elastography measured thickening and stiffening, respectively, one day after neuromuscular blocker liberation (D1), then three (D3), and seven (D7) days after, for patients still receiving MV. Thickening and stiffening were expressed as ratios using baseline measurement at rest. Patients with an MRC score <48 within the 24 hours post-extubation were diagnosed with ICU-Aw. <bold>Results:</bold> Among the 80 patients included (age 60 ±12 years, IGSII score 33 ±15), 39 (49%) developed ICU-Aw. NMES intensity needed to obtain a quadriceps contraction was higher in the ICU-Aw group from D1 (mean difference +281 mA, p<0.01) and D3 (mean difference +244 mA, p=0.014). Thickening and stiffening ratios were slightly lower in the ICU-Aw group, although unsignificant. D1 and D3 NMES intensity could discriminate ICU-Aw (AUC=0.73, p<0.01; and 0.73, p=0.025, respectively). Inter-rater reliability was excellent for NMES intensity (ICC=0.99), and moderate for thickening and stiffening at D1. <bold>Conclusion:</bold> NMES intensity needed to generate muscle contraction seems promising for early identification of ICU-Aw.