Acuson x300

All blood samples were obtained after 8 h of fasting, and subsequently analyzed. Height and weight were measured with the participants wearing light clothing and no shoes. Body mass index was calculated as weight (kg) divided by the square of height (m²). Carotid ultrasound was performed with a high-resolution B-mode ultrasonography system (Acuson X300; Siemens, USA) with a transducer frequency of 13–15 MHz. Computer-assisted acquisition, processing, B-mode image storage, and calculation of intima-media thickness were performed using the Syngo Arterial Health Package (Siemens, USA). Automatic measurements of both common carotid arteries were performed at the far wall of the 1-cm segment distal to the carotid bulbs. Carotid plaque was defined as the presence of focal wall thickening ≥ 50% than that of the surrounding vessel wall or as a focal region with a carotid intima-media thickness of ≥ 1.5 mm, protruding into the lumen and distinct from the neighboring boundary [18 (link), 19 (link)]. A representative image of a carotid plaque is presented in Fig. 1.Fig. 1

Representative image of a carotid plaque. The asterisk indicates a 1.0 × 0.3-cm plaque in the left internal carotid artery of a 54-year-old man

For this study, we used Siemens ACUSON X300™ (Siemens Health Care, Germany) machine for measurement of the muscle thickness. Muscle thickness measurements were done using B-mode of USG using 5.0–13.0 MHz (megahertz) linear array probe (VF 13-5). All measurements were taken by a single operator (RK) who was trained in using bedside USG in ICU.