Objective: To explore the diagnostic accuracy of muscle ultrasound and plasma monocyte chemoattractant protein-1 (MCP-1) for ICU-acquired weakness (ICU-AW) in patients with sepsis.
Methods: A prospective observational study was conducted. Patients with sepsis admitted to the intensive care unit (ICU) of Henan Provincial People's Hospital from April 2021 to October 2021 were enrolled. The demographic data were collected. The enrolled patients were evaluated with Medical Research Council (MRC) score every day until discharged from ICU. During this period, patients with total MRC score < 48 (for two consecutive times and a time interval of 24 hours) were divided into ICU-AW group, those with total MRC score ≥ 48 were served as non-ICU-AW group. On the 1st, 4th and 7th day following admission into ICU, ultrasound was used to measure the muscle linear thickness of the rectus femoris (RF-MLT), the cross sectional area of the rectus femoris (RF-CSA) and the muscle linear thickness of the vastus intermedius muscle (VI-MLT). And meanwhile, the plasmas samples of patients were collected to measure MCP-1 concentration by enzyme-linked immunosorbent assay (ELISA). The difference of each index was compared between the ICU-AW group and the non-ICU-AW group. The risk factors of ICU-AW in patients with sepsis were analyzed by binary Logistic regression. Besides, receiver operator characteristic curve (ROC curve) was plotted, the diagnostic value of ultrasound parameters and plasma MCP-1 level for ICU-AW in patients with sepsis was analyzed.
Results: A total of 99 septic patients were enrolled, with 68 patients in the ICU-AW group and 31 patients in the non-ICU-AW group. Compared with the patients in the ICU-AW group, the patients in the non-ICU-AW group tended to be older, and had higher sequential organ failure assessment (SOFA) score, higher acute physiology and chronic health evaluation II (APACHE II) score, higher rates of septic shock, higher blood lactic acid and lower Glasgow coma score (GCS). Binary Logistic regression analysis showed that APACHE II score and septic shock were the risk factors of ICU-AW for septic patients [odds ratio (OR) and 95% confidence interval (95%CI) were 1.310 (1.138-1.509) and 0.232 (0.072-0.746), respectively, both P < 0.05]. The RF-MLT, RF-CSA and VI-MLT on the 1st, 4th and 7th ICU day was falling over time. Compared with the patients in the ICU-AW group, the patients in the non-ICU-AW group had smaller RF-MLT on the 7th day [cm: 0.32 (0.22, 0.47) vs. 0.45 (0.34, 0.63), P < 0.05] and higher 7-day RF-CSA atrophy rate [25.85% (10.37%, 34.28%) vs. 11.65% (2.28%, 22.41%), P < 0.05]. According to ROC curve analysis, 7-day RF-MLT had diagnostic value for ICU-AW of septic patients. Area under ROC curve (AUC) was 0.688 (95%CI was 0.526-0.849); when the cut-off value was 0.41 cm, the sensitivity and the specificity were 66.7% and 68.4%. The levels of plasma MCP-1 in the ICU-AW group were significantly higher than those in the non-ICU-AW group on the 1st, 4th and 7th day. ROC curve analysis showed that the plasma MCP-1 levels on the 1st, 4th and 7th day played a significant role to diagnose ICU-AW for septic patients, the AUC and 95%CI were 0.732 (0.629-0.836), 0.865 (0.777-0.953), 0.891 (0.795-0.986), respectively. When the cut-off values were 206.3, 410.9, 239.5 ng/L, the sensitivity was 87.1%, 64.0%, 82.4%, and the specificity was 54.4%, 96.1%, 86.2%, respectively.
Conclusions: The muscle mass parameters on the 7th day of bedside ultrasound and plasma MCP-1 levels had certain diagnostic values for ICU-AW in patients with sepsis.