Observational Study
Copyright ©The Author(s) 2020. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Cardiol. Jul 26, 2020; 12(7): 351-361
Published online Jul 26, 2020. doi: 10.4330/wjc.v12.i7.351
Sonographic muscle mass assessment in patients after cardiac surgery
Stavros Dimopoulos, Vasiliki Raidou, Dimitrios Elaiopoulos, Foteini Chatzivasiloglou, Despoina Markantonaki, Efterpi Lyberopoulou, Ioannis Vasileiadis, Katerina Marathias, Serafeim Nanas, Andreas Karabinis
Stavros Dimopoulos, Dimitrios Elaiopoulos, Despoina Markantonaki, Efterpi Lyberopoulou, Katerina Marathias, Andreas Karabinis, Department of Cardiac Surgery ICU, Onassis Cardiac Surgery Center, Athens 17674, Greece
Stavros Dimopoulos, Vasiliki Raidou, Foteini Chatzivasiloglou, Ioannis Vasileiadis, Serafeim Nanas, Clinical Ergospirometry, Exercise and Rehabilitation Laboratory, National and Kapodistrian University of Athens, Athens 10676, Greece
Author contributions: Dimopoulos S conceptualized and designed the study; Karabinis A supervised the study; Dimopoulos S, Raidou V, Markantonaki D, Marathias K, Vasileiadis I and Nanas S were involved in the data curation and analysis, projet administration and provided scientific review; Dimopoulos S, Raidou V, Elaiopoulos D, Chatzivasiloglou F and Lyberopoulou E performed the research and collected the data; Dimopoulos S and Raidou V wrote the paper, reviewed, edited and revised the final version of the manuscript; all authors have read and approved the final manuscript.
Institutional review board statement: The study was reviewed and approved by Ethics Committee of the Onassis Cardiac Surgery Center, Athens, Greece, No. 607/17.11.17.
Informed consent statement: Patients were not required to give informed consent to the study because the analysis used anonymous data that were obtained after each patient agreed to treatment by written consent.
Conflict-of-interest statement: There are no conflicts of interest to report.
Data sharing statement: No additional data are available.
STROBE statement: The authors have read the STROBE Statement—checklist of items, and the manuscript was prepared and revised according to the STROBE Statement—checklist of items.
Open-Access: This article is an open-access article that was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution NonCommercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/
Corresponding author: Stavros Dimopoulos, PhD, Doctor, Postdoc, Research Scientist, Senior Researcher, Staff Physician, Department of Cardiac Surgery ICU, Onassis Cardiac Surgery Center, No. 356 L. Syggrou, Athens 17674, Greece. stdimop@gmail.com
Received: February 29, 2020
Peer-review started: February 29, 2020
First decision: April 7, 2020
Revised: May 11, 2020
Accepted: June 17, 2020
Article in press: June 17, 2020
Published online: July 26, 2020
Processing time: 146 Days and 5.9 Hours
ARTICLE HIGHLIGHTS
Research background

Intensive care unit (ICU) acquired weakness (ICUAW) remains a major cause of mortality and morbidity in critically ill patients. Ultrasonography is a valid diagnostic tool in critical ill patients who present muscle weakness. Muscle wasting may occur in cardiac surgery patients’ post-ICU admission affecting outcome. Early detection of muscle wasting may benefit interventions to decrease the duration of mechanical ventilation, increase muscle strength and improve their quality of life.

Research motivation

Sonography is a diagnostic method that allows the assessment of muscle mass in bedridden. It has been introduced recently as a valid and reliable to measure quantity and quality of skeletal muscle. It's a non-invasive, low-cost method offering real-time imaging without radiation exposure.

Research objectives

The clinical value of ultrasound-assessed muscle mass in patients post-cardiac surgery ICU admission.

Research methods

An observational study was conducted to 221 consecutive patients after cardiac surgery at the Cardiac Surgery ICU of Onassis Cardiac Surgery Center from February 1, 2018 to May 15, 2018. Sonographic assessment of quadriceps muscle thickness and evaluation of muscle strength using the Medical Research Council (MRC) scale were performed until 7th day post-ICU admission or ICU discharge.

Research results

Among the 165 patients finally included in the analysis [median age: 71 (64-77) years], there was a decrease of femoris muscle thickness by 2.2% [(95% confidence interval (CI): - 0.21 to 0.15), n = 9; P = 0.729] and vastus intermedius mass (RF_VI mass) decreased by 3.5% [(95%CI: - 0.4 to 0.22), n = 9; P = 0.530]. Patients with RF_VI mass below the recorded median values (2.5 cm) on day 1 (n = 80) had a longer ICU length of stay compared to those patients with RF_VI mass above than 2.5 cm (n = 85), (47 ± 74 h vs 28 ± 45 h, P = 0.02) and remained to MV more time, (17 ± 9 h vs 14 ± 9 h, P = 0.05). Patients with ICUAW on day 3 (n = 7) had prolonged ventilation (44 ± 14 h vs 19 ± 9 h, P = 0.006) compared to patients with no ICUAW (n = 33). Moreover, the duration of extracorporeal circulation was greater for patients with low MRC scale score on day 3 (n = 7) compared with patients with higher MRC scale score (n = 33), (159 ± 91 min vs 112 ± 71 min, P = 0.025).

Research conclusions

The results of the study have shown that there is a trend to a decreased muscle mass in patients after cardiac surgery post-ICU admission. Patients with decreased muscle mass remained more on ventilator and stayed longer in ICU. Sonographic assessment seems to be a valid method to quantify quadriceps muscle mass in patients after cardiac surgery.

Research perspectives

We advocate further research to investigate muscle wasting in patients after cardiac surgery in order to implement preventive measures for ICU acquired weakness. Furthermore, it is recommended to identify a standardized protocol for sonographic muscle mass assessment to be implemented in research studies and intervention protocols.