Sonographic Evaluation of Muscle Echogenicity for the Detection of Intensive Care Unit-Acquired Weakness: A Pilot Single-Center Prospective Cohort Study

Potential diagnostic tools for intensive care unit acquired weakness: A systematic review

Background

Intensive care unit-acquired weakness is a prevalent complication among critically ill patients, associated with heightened mortality rates, extended durations of mechanical ventilation and hospital stays, as well as diminished mobility and unfavorable prognoses. Early diagnosis of intensive care unit-acquired weakness and identification of its subcategories are essential for early implementation of targeted interventions and care strategies. Nevertheless, there remains a significant gap in the availability of widely accepted, accurate, and user-friendly diagnostic tools for intensive care unit-acquired weakness.

Objective

The aim of this research was to conduct a comprehensive review of pertinent studies on diagnostic tools for intensive care unit-acquired weakness in critically ill patients, summarizing their diagnostic efficacy and constraints to aid healthcare professionals in choosing suitable diagnostic tools for intensive care unit-acquired weakness.

Methods

The Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) statement were utilized to direct the literature search, bias risk assessment and data extraction. The search databases included PubMed, Web of Science, EMBASE, Cochrane Library, and CINAHL. The search period was from the inception of the database to 1 July 2024. Different types of risk bias assessment tools were used for different types of studies. Due to the heterogeneity of the data, solely a narrative synthesis of the intensive care unit-acquired weakness diagnostic tool was performed in this study.

Results

A total of 38 observational studies were included in the study. In the included studies, the gold standard for intensive care unit-acquired weakness diagnosis include the Medical Research Council score, muscle biopsy and electrophysiologic testing, potential diagnostic tools include the manual muscle test, electrophysiologic testing, imaging, serum inflammatory markers, neuromuscular ultrasound, and other parameters. In various studies, the diagnostic accuracy of intensive care unit-acquired weakness diagnostic tools has been inconsistent, with each tool possessing its own set of advantages and disadvantages. At present, no single tool is available for the definitive diagnosis of intensive care unit-acquired weakness, necessitating the combined use of multiple methods, each with inherent limitations. Manual muscle test is inexpensive and straightforward to perform, but it requires the patient to be conscious and cooperative. Muscle biopsy is invasive and rarely utilized. Electrophysiological testing can help differentiate whether intensive care unit-acquired weakness is caused by neural or muscular alterations, thereby aiding in the classification of its subtypes. However, it is moderately invasive, costly, and operator-dependent. Other diagnostic modalities, such as imaging and respiratory parameters, are under ongoing investigation.

Conclusions

The diagnostic tools available in intensive care unit-acquired weakness are varied, each with its own strengths and limitations. This study summarizes the current evidence on potential diagnostic tools for intensive care unit-acquired weakness and identifies possible future directions for these diagnostic tools.

Registration

PROSPERO Registration Number CRD42024573139.

Developing a reliable and convenient methodology for ultrasound muscle assessment in critically ill patients: A reliability study

This study proposed a reliable and convenient methodology to assess rectus femoris (RF) and gastrocnemius muscles using ultrasound in critically ill patients. The focus was on reliability and convenience, considering both intra- and inter-observer reliability in the ICU and outpatient clinical settings. The RF and gastrocnemius muscles of 23 patients in the ICU were assessed using ultrasound. Two assessors, an expert and a novice, performed measurements across 2 consecutive days. Muscle thickness (MT), cross-sectional area (CSA), and echogenicity were measured in the RF, while MT, echogenicity, and pennate angle were measured in the gastrocnemius. The intra-class correlation coefficient (ICC) was assessed for intra- and inter-rater reliability for all markers. Intra- and inter-observer reliability was almost perfect (ICC > 0.80) for all markers, irrespective of the assessor's expertise. The CSA of the RF muscle exhibited the highest reliability (ICC > 0.95). MT of the gastrocnemius also demonstrated high intra- and inter-observer reliability (ICC > 0.91). In echogenicity measurements, gastrocnemius showed the highest (ICC > 0.91) intra- and inter-observer reliability. Ultrasound measurement of RF and gastrocnemius muscles in critically ill patients using the proposed methods demonstrated almost perfect reliability in both muscle mass and quality measurements. These methodologies, prioritizing convenience and reliability, could be employed for evaluating muscle status and changes in ICU settings and outpatient follow-ups.

Longitudinal Assessment of Blood-Based Inflammatory, Neuromuscular, and Neurovascular Biomarker Profiles in Intensive Care Unit-Acquired Weakness: A Prospective Single-Center Cohort Study

BACKGROUND

The diagnosis of intensive care unit (ICU)-acquired weakness (ICUAW) and critical illness neuromyopathy (CINM) is frequently hampered in the clinical routine. We evaluated a novel panel of blood-based inflammatory, neuromuscular, and neurovascular biomarkers as an alternative diagnostic approach for ICUAW and CINM.

METHODS

Patients admitted to the ICU with a Sequential Organ Failure Assessment score of ≥ 8 on 3 consecutive days within the first 5 days as well as healthy controls were enrolled. The Medical Research Council Sum Score (MRCSS) was calculated, and motor and sensory electroneurography (ENG) for assessment of peripheral nerve function were performed at days 3 and 10. ICUAW was defined by an MRCSS < 48 and CINM by pathological ENG alterations, both at day 10. Blood samples were taken at days 3, 10, and 17 for quantitative analysis of 18 different biomarkers (white blood cell count, C-reactive protein, procalcitonin, C-terminal agrin filament, fatty-acid-binding protein 3, growth and differentiation factor 15, syndecan 1, troponin I, interferon-γ, tumor necrosis factor-α, interleukin-1α [IL-1α], IL-1β, IL-4, IL-6, IL-8, IL-10, IL-13, and monocyte chemoattractant protein 1). Results of the biomarker analysis were categorized according to the ICUAW and CINM status. Clinical outcome was assessed after 3 months.

RESULTS

Between October 2016 and December 2018, 38 critically ill patients, grouped into ICUAW (18 with and 20 without) and CINM (18 with and 17 without), as well as ten healthy volunteers were included. Biomarkers were significantly elevated in critically ill patients compared to healthy controls and correlated with disease severity and 3-month outcome parameters. However, none of the biomarkers enabled discrimination of patients with and without neuromuscular impairment, irrespective of applied classification.

CONCLUSIONS

Blood-based biomarkers are generally elevated in ICU patients but do not identify patients with ICUAW or CINM.

TRIAL REGISTRATION

ClinicalTrials.gov identifier: NCT02706314.

USE OF MUSCULAR ULTRASOUND TO DETECT INTENSIVE CARE UNIT-ACQUIRED WEAKNESS: A SYSTEMATIC REVIEW AND META-ANALYSIS

ABSTRACT

Background : This systematic review and meta-analysis aims to detecting performance of muscular ultrasound for intensive care unit (ICU)-acquired weakness (ICUAW). Methods : We searched PubMed, Web of Science, Embase, Cochrane library, CNKI, VIP, and Wanfang databases for articles published before July 2024. A random-effects model was utilized to derive the summary estimates of sensitivity, specificity, and diagnostic odds ratio (DOR) with 95% confidence interval (CI). Additionally, the sources of heterogeneity were explored by subgroup analysis and meta-regression. Results : This meta-analysis comprised 10 prospective studies involving 561 participants, of whom 241 (42.96%) were diagnosed as ICUAW. Overall, muscular ultrasound exhibited good performance for detecting ICUAW, with the area of summary receiver operating characteristic (SROC) curve of 0.85 (95%CI 0.82-0.88), sensitivity of 0.76 (95%CI 0.70-0.81), specificity of 0.80 (95%CI 0.74-0.84), and DOR of 12.43 (95%CI 7.98-19.38). Upon predefined subgroup analysis, the rectus femoris exhibited significantly superior discriminatory ability in identifying ICUAW than the non-rectus femoris, with higher SROC (0.88 [95%CI 0.85-0.91] vs. 0.76 [95%CI 0.72-0.79], P < 0.01). Moreover, cross-sectional area was more effective than thickness, with higher specificity (0.86 [95%CI 0.80-0.91] vs. 0.74 [95%CI 0.68-0.79], P = 0.02) and SROC (0.89 [95%CI 0.86-0.92] vs. 0.76 [95%CI 0.72-0.80], P < 0.01). Furthermore, integrated analysis of these two indicators revealed that the cross-sectional area of rectus femoris was statistically superior to the thickness of rectus femoris, with higher sensitivity (0.82 [95%CI 0.74-0.87] vs. 0.75 [95%CI 0.65-0.83], P < 0.05) and AUC (0.91 [95%CI 0.88-0.93] vs. 0.80 [95%CI 0.76-0.83], P < 0.01). Conclusions : Muscular ultrasound could be a reliable tool for ICUAW detection. Compared with alternative indices, the cross-sectional area of the rectus femoris exhibits superior detection efficacy and may be considered as a valuable parameter for clinical application.

Skeletal muscle as a pro- and anti-inflammatory tissue: insights from children to adults and ultrasound findings

Previously regarded as a movement and posture control agent, the skeletal muscle is now recognized as an endocrine organ that may affect systemic inflammation and metabolic health. The discovery of myokines such as IL-6, released from skeletal muscle in response to physical exercise, is now one of the most recent insights. Myokines are the mediators of the balance between the pro-inflammatory and anti-inflammatory responses. This underscores the muscle function as a determinant of good health and prevention of diseases. Advances in ultrasound technology improved evaluation of muscle thickness, composition, and determining fat distribution. Combining imaging with molecular biology, researchers discovered the complicated interplay between muscle function, cytokine production and general health effects.The production of myokines with exercise showcasing the adaptability of muscles to high-stress conditions and contributing to metabolism and inflammation regulation. These findings have significant implications in order to provide improvement in metabolic and inflammatory diseases.

Effectiveness and feasibility of 5G-based remote interactive ultrasound training in critical care

BACKGROUND

Ultrasound has widely used in various medical fields related to critical care. While online and offline ultrasound trainings are faced by certain challenges, remote ultrasound based on the 5G cloud platform has been gradually adopted in many clinics. However, no study has used the 5G remote ultrasound cloud platform operating system for standardized critical care ultrasound training. This study aimed to evaluate the feasibility and effectiveness of 5G-based remote interactive ultrasound training for standardized diagnosis and treatment in critical care settings.

METHODS

A 5G-based remote interactive ultrasound training system was constructed, and the course was piloted among critical care physicians. From July 2022 to July 2023, 90 critical care physicians from multiple off-site locations were enrolled and randomly divided into experimental and control groups. The 45 physicians in the experimental group were trained using the 5G-based remote interactive ultrasound training system, while the other 45 in the control group were taught using theoretical online videos. The theoretical and practical ultrasonic capabilities of both groups were evaluated before and after the training sessions, and their levels of satisfaction with the training were assessed as well.

RESULTS

The total assessment scores for all of the physicians were markedly higher following the training (80.7 ± 11.9) compared to before (42.1 ± 13.4) by a statistically significant margin (P < 0.001). Before participating in the training, the experimental group scored 42.2 ± 12.5 in the critical care ultrasound competency, and the control group scored 41.9 ± 14.3-indicating no significant differences in their assessment scores (P = 0.907). After participating in the training, the experimental group's assessment scores were 88.4 ± 6.7, which were significantly higher than those of the control group (72.9 ± 10.8; P < 0.001). The satisfaction score of the experimental group was 42.6 ± 2.3, which was also significantly higher than that of the control group (34.7 ± 3.1, P < 0.001).

CONCLUSION

The 5G-based remote interactive ultrasound training system was well-received and effective for critical care. These findings warrant its further promotion and application.

Program with last minute abstracts of the Padua Days on Muscle and Mobility Medicine, 27 February - 2 March, 2024 (2024Pdm3)

During the 2023 Padua Days on Muscle and Mobility Medicine the 2024 meeting was scheduled from 28 February to 2 March 2024 (2024Pdm3). During autumn 2023 the program was expanded with Scientific Sessions which will take place over five days (in 2024 this includes February 29), starting from the afternoon of 27 February 2024 in the Conference Rooms of the Hotel Petrarca, Thermae of Euganean Hills (Padua), Italy. As per consolidated tradition, the second day will take place in Padua, for the occasion in the Sala San Luca of the Monastery of Santa Giustina in Prato della Valle, Padua, Italy. Confirming the attractiveness of the Padua Days on Muscle and Mobility Medicine, over 100 titles were accepted until 15 December 2023 (many more than expected), forcing the organization of parallel sessions on both 1 and 2 March 2024. The five days will include lectures and oral presentations of scientists and clinicians from Argentina, Austria, Belgium, Brazil, Bulgaria, Canada, Denmark, Egypt, France, Germany, Iceland, Ireland, Italy, Romania, Russia, Slovenia, Switzerland, UK and USA. Only Australia, China, India and Japan are missing from this edition. But we are confident that authors from those countries who publish articles in the PAGEpress: European Journal of Translational Myology (EJTM: 2022 ESCI Clarivate's Impact Factor: 2.2; SCOPUS Cite Score: 3.2) will decide to join us in the coming years. Together with the program established by 31 January 2024, the abstracts will circulate during the meeting only in the electronic version of the EJTM Issue 34 (1) 2024. See you soon in person at the Hotel Petrarca in Montegrotto Terme, Padua, for the inauguration scheduled the afternoon of 27 February 2024 or on-line for free via Zoom. Send us your email address if you are not traditional participants listed in Pdm3 and EJTM address books.

Ultrasound for measurement of skeletal muscle mass quantity and muscle composition/architecture in critically ill patients: A scoping review on studies' aims, methods, and findings

AIMS

This scoping review aimed to identify, explore, and map the objectives, methodological aspects, and results of studies that used ultrasound (US) to assess skeletal muscle (SM) in critically ill patients.

METHODS

A scoping review was conducted according to the Joanna Briggs Institute's methodology. All studies that evaluated SM parameters from the US in patients admitted to the intensive care unit (ICU) were considered eligible. We categorized muscle thickness and cross-sectional area as parameters for assessing SM quantity, while echogenicity, fascicle length, and pennation angle analysis were used to evaluate muscle "quality" (composition/architecture). A literature search was conducted using four databases for articles published until December 2022. Independent reviewers selected the studies and extracted data. Descriptive statistics were calculated to present the results.

RESULTS

A total of 107 studies were included, the majority of which were prospective cohort studies (59.8 %) conducted in general ICUs (49.5 %). The most frequent objective of the studies was to evaluate SM quantity depletion during the ICU stay (25.2 %), followed by determining whether a specific intervention would modify SM (21.5 %). Most studies performed serial SM evaluations (76.1 %). The rectus femoris muscle thickness was evaluated in most studies (67.9 %), followed by the rectus femoris cross-sectional area (54.3 %) and the vastus intermedius muscle thickness (40.2 %). The studies demonstrated the feasibility and reproducibility of US for SM evaluation, especially related to quantitative parameters. Most studies (70.3 %) reported significant SM quantity depletion during hospitalization. However, the accuracy of the US in measuring SM varied across the studies.

CONCLUSIONS

The lack of detailed description and standardization in the protocols adopted by the studies included in this scoping review precludes the translation of the evidence related to US for SM assessment into clinical practice.

Attenuating Muscle Mass Loss in Critical Illness: the Role of Nutrition and Exercise

PURPOSE OF REVIEW

Impaired recovery following an intensive care unit (ICU) admission is thought related to muscle wasting. Nutrition and physical activity are considered potential avenues to attenuate muscle wasting. The aim of this review was to present evidence for these interventions in attenuating muscle loss or improving strength and function.

RECENT FINDINGS

Randomised controlled trials on the impact of nutrition or physical activity interventions in critically ill adult patients on muscle mass, strength or function are presented. No nutrition intervention has shown an effect on strength or function, and the effect on muscle mass is conflicting. RCTs on the effect of physical activity demonstrate conflicting results; yet, there is a signal for improved strength and function with higher levels of physical activity, particularly when commenced early. Further research is needed to elucidate the impact of nutrition and physical activity on muscle mass, strength and function, particularly in combination.

Ultrasound Measurements of Rectus Femoris and Locomotor Outcomes in Patients with Spinal Cord Injury

Patients with incomplete spinal cord injury have decreased mobility, and many do not recover walking ability. The purpose of this study was to investigate rectus femoris muscle thickness and echo intensity on ultrasound and functional outcomes in these patients. This was a prospective cohort study in an inpatient rehabilitation center, which recruited 40 consecutive patients with incomplete spinal cord injury. The patients underwent an ultrasound assessment at 6 weeks post-injury. Ultrasound measurements were performed using B-mode ultrasound scanning and standardized protocols. Functional outcomes on discharge, including Lower Extremity Muscle Score (LEMS), Functional Independence Measure (FIM), and Walking Index for Spinal Cord Injury II (WISCI II), were measured. Rectus femoris muscle thickness was significantly correlated with discharge LEMS (Spearman’s rho = 0.448; p = 0.004), FIM motor subscale (Spearman’s rho = 0.595; p < 0.001), FIM walk subscale (Spearman’s rho = 0.621; p < 0.001) and WISCI II (Spearman’s rho = 0.531; p < 0.001). The rectus femoris echo intensity was also significantly correlated with discharge LEMS (Spearman’s rho = −0.345; p = 0.029), FIM motor subscale (Spearman’s rho = −0.413; p = 0.008), FIM walk subscale (Spearman’s rho = −0.352; p = 0.026), and WISCI II (Spearman’s rho = −0.355; p = 0.025). We report that a relationship exists between rectus femoris muscle ultrasonographic characteristics and muscle function and ambulatory outcomes after inpatient rehabilitation. Ultrasound muscle measurements are potentially useful in assessing muscle wasting and function in patients with spinal cord injury.