METHODS: A prospective observational study was conducted. A total of 55 patients with sepsis admitted to ICU of General Hospital of Ningxia Medical University from June 2022 to February 2023 were selected as the research objects. General information, laboratory indicators [urea, serum creatinine (SCr), and UCR] on days 1, 4, and 7 of ICU admission, and prognostic indicators were observed. Bedside ultrasound was used to assess the dynamic changes of diaphragm morphology [including diaphragmatic excursion (DE), end-inspiratory diaphragm thickness (DTei), and end-expiratory diaphragm thickness (DTee)] on days 1, 4, and 7 of ICU admission, as well as limb skeletal muscle (quadriceps femoris) morphology [including rectus femoris-muscle layer thickness (RF-MLT), vastus intermedius-muscle layer thickness (VI-MLT), and rectus femoris-cross sectional area (RF-CSA)]. Diaphragm thickening fraction (DTF) and RF-CSA atrophy rate were calculated, and the incidence of diaphragm and limb skeletal muscle dysfunction was recorded. The correlation between ultrasound morphological parameters of diaphragm and quadriceps and UCR at each time points in 7 days after ICU admission was analyzed by Pearson correlation.
RESULTS: A total of 55 patients with sepsis were included, of which 29 were in septic shock. As the duration of ICU admission increased, the incidence of diaphragm dysfunction in patients with sepsis increased first and then decreased (63.6%, 69.6%, and 58.6% on days 1, 4, and 7 of ICU admission, respectively), while the incidence of limb skeletal muscle dysfunction showed an increasing trend (54.3% and 62.1% on days 4 and 7 of ICU admission, respectively), with a probability of simultaneous occurrence on days 4 and 7 of ICU admission were 32.6% and 34.5%, respectively. The UCR on day 7 of ICU admission was significantly higher than that on day 1 [121.77 (95.46, 164.55) vs. 97.00 (70.26, 130.50)], and RF-CSA atrophy rate on day 7 was significantly higher than that on day 4 [%: -39.7 (-52.4, -22.1) vs. -26.5 (-40.2, -16.4)]. RF-CSA was significantly lower on day 7 compared to day 1 [cm2: 1.3 (1.0, 2.5) vs. 2.1 (1.7, 2.9)], with all differences being statistically significant (all P < 0.05). Pearson correlation analysis showed that RF-CSA on day 7 of ICU admission was negatively associated with the UCR on the same day (r = -0.407, P = 0.029).
CONCLUSIONS: Diaphragmatic dysfunction in patients with sepsis occurred early and can be improved. Limb skeletal muscle dysfunction occurred relatively later and progresses progressively. The RF-CSA on day 7 of ICU admission may be a reliable measure of limb skeletal muscle dysfunction in patients with sepsis, can be an indicator of early identification and diagnosis of ICU-acquired weakness (ICU-AW). Continuous loss of muscle mass occurring in septic patients is mainly associated with persistent organismal catabolism, and undergoes significant changes around a week in ICU.
方法:进行前瞻性观察性研究。选取2022年6月至2023年2月宁夏医科大学总医院ICU收治的55例脓毒症患者作为研究对象。一般信息,实验室指标[尿素,血清肌酐(SCr),和UCR]在ICU入院的第1、4和7天,并观察预后指标。床旁超声用于评估膈肌形态的动态变化[包括膈肌偏移(DE),吸气末隔膜厚度(DTei),和呼气末隔膜厚度(DTee)]在ICU入院的第1、4和7天,以及肢体骨骼肌(股四头肌)形态[包括股直肌层厚度(RF-MLT),中间肌-肌层厚度(VI-MLT),和股直肌横截面积(RF-CSA)]。计算膈肌增厚分数(DTF)和RF-CSA萎缩率,记录膈肌和肢体骨骼肌功能障碍的发生率。采用Pearson相关性分析ICU入住后7天各时间点膈肌、股四头肌超声形态学参数与UCR的相关性。
结果:共纳入55例脓毒症患者,其中29例发生感染性休克。随着ICU住院时间的增加,脓毒症患者膈肌功能障碍的发生率先升高后降低(63.6%,69.6%,入住ICU的第1天、第4天和第7天的58.6%,分别),而肢体骨骼肌功能障碍的发生率呈上升趋势(入住ICU第4天和第7天分别为54.3%和62.1%,分别),在入住ICU的第4天和第7天同时发生的概率分别为32.6%和34.5%,分别。入住ICU第7天的UCR明显高于第1天[121.77(95.46,164.55)vs.97.00(70.26,130.50)],第7天的RF-CSA萎缩率明显高于第4天[%:-39.7(-52.4,-22.1)vs.-26.5(-40.2,-16.4)]。与第1天相比,第7天的RF-CSA显着降低[cm2:1.3(1.0,2.5)与2.1(1.7,2.9)],差异均有统计学意义(均P<0.05)。Pearson相关分析显示,ICU入住第7天的RF-CSA与当天的UCR呈负相关(r=-0.407,P=0.029)。
结论:脓毒症患者膈肌功能障碍发生早,可得到改善。四肢骨骼肌功能障碍发生得相对较晚,进展缓慢。ICU入院第7天的RF-CSA可能是脓毒症患者肢体骨骼肌功能障碍的可靠指标。可作为ICU获得性肌无力(ICU-AW)早期识别和诊断的指标。脓毒症患者肌肉质量的持续丢失主要与持续的机体分解代谢有关,并在ICU中一周左右发生重大变化。