Peripheral muscular ultrasound as outcome assessment tool in critically ill patients on mechanical ventilation: An observational cohort study

PTP1B AND ZONULIN FAILED TO PREDICT THE MODIFICATION OF MUSCLE MASS IN CRITICALLY ILL PATIENTS WITH SEPTIC SHOCK

ABSTRACT

Background: Proteolyse is one of the causes of loss of lean body mass, and depend of insulin. Proteintyrosine phosphatase 1B (PTP1B) and intestinal permeability (evaluated by zonulin) contribute of insulin metabolism. The objectives were to explore the relationship between PTP1B, zonulin level and body composition during septic shock in humans. Material and Methods: This is a prospective study including patients admitted to intensive care unit for septic shock. Blood samples were collected on days 1 (D1) and 4 (D4) for study expression of PTPT1b (PCR) and zonulin. Muscle mass was evaluated by fat-free mass (by Bioelectrical impedance analysis) and rectum femoris cross-sectional area by ultrasound. Results: We included 52 patients with a mean IGSII 53 (39-65), and a mortality in intensive care unit of 32%. Between D1 and D4, area of right quadriceps muscle and average of quadriceps muscles decreased ( P = 0.002 and 0.009, respectively). We observed no modification in fat-free mass. Median of PTP1b at D1 was 5.03 (2.36-10.96). Median of plasmatic zonulin at D1 was 156.6 ng/mL (56.3-277.9). We did not find any correlation between PTP1b, zonulin expression, and muscle composition. The mortality rate was more important in patients with a low average quadriceps thickness (QT) or quadriceps area (QA) ( P < 0.01), and tendency for patients who had an elevated zonulin in admission. By contrast, we did not observe significant associations between fat-free mass and PTP1B and mortality at D28. Conclusion: We observed a trend of correlation between the whole blood PTPN1 gene expression at D1 and D4/D1 thickness of left quadriceps muscle, because this is the only data which has a potential to address the relationship body mass change and proteolysis.

Screening for low muscularity and sarcopenia risk using thigh ultrasound in critically ill oncology patients: A prospective cohort study

BACKGROUND & AIMS

Oncological patients frequently suffer from weight loss, reduced strength, and muscle mass depletion, negatively impacting prognosis and quality of life. This often necessitates intensive care unit (ICU) treatment, where muscle loss is further exacerbated, increasing the risk of sarcopenia. This study aimed to investigate the predictive performance of quadriceps ultrasound as an initial screening tool for reduced muscularity and sarcopenia risk in critically ill oncology patients, using computed tomography (CT) as the comparative standard.

METHODS

In this prospective cohort study, patients admitted to an oncological intensive care unit (ICU) between March 2021 and February 2023 were included if they remained in the intensive care unit (ICU) for at least 24 h, had clear third lumbar vertebra (L3) visualization on computed tomography (CT), and provided informed consent. Patients were excluded if they were under palliative care, had amputations of the lower limbs, or had poor-quality computed tomography (CT) imaging that did not allow for accurate assessment. Quadriceps muscle thickness was assessed upon intensive care unit (ICU) admission using the VALIDUM method and compared with computed tomography (CT) findings.

RESULTS

A total of 88 patients were included (mean age 60.6 ± 13.0 years). The most effective method for assessing low muscle mass was ultrasound measurement at two-thirds of the thigh with compression, with a cutoff point of 1.29 cm, yielding a sensitivity of 73.21 % and specificity of 78.12 %. Significant associations were found between measurements below 1.29 cm and lower weight, body mass index (BMI), and skeletal muscle mass index.

CONCLUSIONS

Quadriceps ultrasound upon intensive care unit (ICU) admission is a reliable screening method for detecting low muscle mass in critically ill oncological patients, allowing for early intervention to address sarcopenia risk.

Prospective ultrasonographic evaluation of femoral and vastus intermedius muscles as predictors of ICU-acquired weakness in critically ill patients

PURPOSE

Intensive care unit-acquired weakness (ICU-AW) is associated with poor functional outcomes and increased healthcare costs. This study aimed to evaluate the diagnostic performance of muscular ultrasound (MUS) measurements in predicting ICU-AW and identify potential predictors.

METHODS

Forty-three surgical and medical ICU patients underwent serial MUS measurements of the femoral cross-sectional area (Fcsa) and femoral + vastus intermedius thickness (F + VIth) on days 1, 3 and 5 post-ICU admission. Patients were categorized as having ICU-AW (Medical Research Council (MRC) sum score < 48 at discharge) or not. Univariate and multivariate logistic regression analyses were performed to identify predictors of ICU-AW. The diagnostic performance of MUS measurements was assessed via receiver operating characteristic (ROC) curves. Clinical outcomes (ICU length of stay, ventilator days, extubation failure) were compared between the groups.

RESULTS

Patients with ICU-AW (n = 12, 28%) showed a significant reduction in the Fcsa from Day 1 to Day 5 (p < 0.001). Univariate analysis revealed significant associations between ICU-AW and the Apache II score (OR 1.12, p = 0.03), SOFA score (OR 1.32, p = 0.008), and Day 1 F + VIth score (OR 0.23, p = 0.05). Multivariate analysis confirmed a significant association with the SOFA score (OR 1.35, p = 0.04) and a trend toward an F + VIth score of Day 1 (OR 0.12, p = 0.09). The day 1 Fcsa and F + VIth demonstrated moderate predictive capabilities for ICU-AW (ROC-AUC values of 0.72 and 0.82, respectively). ICU-AW patients experienced longer ICU stays, more ventilator days, and higher extubation failure rates.

CONCLUSION

Preexisting low muscle mass, combined with a high SOFA score, may be a stronger predictor of ICU-acquired weakness than the degree of subsequent muscle loss.

Early detection of muscle wasting assessed by ultrasound and analysis of growth factor and systemic inflammation mediators in critically ill trauma patients: an observational study

PURPOSE

The present study aims to describe initial changes in muscle thickness and composition, muscle growth signaling mediators, and systemic inflammation in critically ill patients after major trauma.

METHODS

This observational study was carried out in a Level-I nonprofit trauma center. Thirty adults requiring mechanical ventilation were assessed within 24 h post-admission. Skeletal muscle wasting was evaluated using ultrasound for muscle thickness and echogenicity along with circulating insulin-like growth factor 1 (IGF-1) and inflammatory cytokines over five consecutive days. Changes over time were assessed using ANOVA repeated-measures analysis with a Bonferroni post-hoc test. Bivariate correlations were evaluated using Pearson or Spearman coefficients.

RESULTS

Over five days, a significant decrease (11%) in rectus femoris thickness (3.91 ± 0.86 to 3.47 ± 0.64, cm, p = 0.01) and an increase (29%) in echogenicity (62.1 ± 13.1 to 80.4 ± 17.3, AU, p < 0.01) were observed among the 30 patients included in this study. Circulating levels of IGF-1 exhibited a 38% reduction (68.8 ± 43.6 to 42.4 ± 29.4, ng/mL, p = 0.01). Furthermore, pro-inflammatory cytokine (IFN-y) increased by 17% (4.83 ± 1.39 to 5.66 ± 1.61, pg./mL, p = 0.02) from day 1 to day 5.

CONCLUSIONS

These findings reveal substantial thickness and muscle composition alterations within 48 h post-admission, worsening over five days. Despite standard rehabilitation care, changes in IGF-1 and IFN-y levels suggest early declines in muscle growth stimulus and increased inflammation.

Ultrasound assessment of muscle mass in critically ill patients: A correlation with nutritional support and clinical outcomes

BACKGROUND

Critically ill patients are at high risk of Intensive Care Unit (ICU) Acquired weakness, which negatively impacts clinical outcomes. Traditional muscle mass and nutritional status assessments are often impractical in the ICU. Ultrasound offers a promising, non-invasive alternative. This study evaluates the relationship between ultrasound-based muscle assessments, patients' nutritional support, and clinical outcomes in the ICU.

METHODS

A prospective cohort study was conducted in three ICUs of a tertiary center. Daily nutritional intake, ultrasound measurements of the quadriceps muscle (rectus femoris cross-sectional area - RFCSA - and quadriceps muscle layer thickness - QMLT), and clinical data were collected on days 1, 3, and 7 of ICU.

RESULTS

A total of 128 patients were included in the analysis, with a mean age of 65.4 (±18.1) years and a median ICU stay of 6 (4-10) days. QMLT decreased by 5 % and 13 %, and RFCSA decreased by 10 % and 27 % on days 3 and 7, respectively. A significant correlation was found between lower caloric and protein intake and greater muscle mass loss within the initial 3 days of ICU admission. Multivariate logistic regression indicated that QMLT reduction significantly contributed to 28-day mortality (adjusted OR 1.088, 95 % CI: 1.018-1.113, p = 0.015). Lower daily caloric and protein intake was depicted in non-surviving patients (p < 0.001).

CONCLUSIONS

Our study demonstrates that critically ill patients experience significant muscle mass loss within the first 72 h of ICU. QMLT reduction significantly impacts 28-day mortality, with an 8.8 % increase in the odds of death per 0.1 cm reduction.

Acute Sarcopenia: Systematic Review and Meta-Analysis on Its Incidence and Muscle Parameter Shifts During Hospitalisation

BACKGROUND

Acute sarcopenia is sarcopenia lasting less than 6 months, typically following acute illness or injury. It may impact patient recovery and quality of life, advancing to chronic sarcopenia. However, its development and assessment remain poorly understood, particularly during hospitalisation. This systematic review aimed to elucidate the incidence of acute sarcopenia and examine changes in muscle parameters during hospitalisation.

METHODS

Eighty-eight papers were included in the narrative synthesis; 33 provided data for meta-analyses on the effects of hospitalisation on handgrip strength (HGS), rectus femoris cross-sectional area (RFCSA) and various muscle function tests. Meta-regressions were performed for length of hospital stay (LoS) and age for all meta-analyses; sex was also considered for HGS.

RESULTS

Acute sarcopenia development was assessed in four studies with a pooled incidence of 18% during hospitalisation. Incidence was highest among trauma patients in intensive care (59%), whereas it was lower among medical and surgical patients (15%-20%). Time of development ranged from 4 to 44 days. HGS remained stable during hospitalisation (SMD = 0.05, 95% CI = -0.18:0.28, p = 0.67) as did knee extensor strength. LoS affected HGS performance (θ = 0.04, 95% CI = 0.001:0.09, p = 0.045) but age (p = 0.903) and sex (p = 0.434) did not. RFCSA, reduced by 16.5% over 3-21 days (SMD = -0.67, 95% CI = -0.92:-0.43, p < 0.001); LoS or time between scans did significantly predict the reduction (θ = -0.04, 95% CI = -0.077:-0.011, p = 0.012). Indices of muscle quality also reduced. Muscle function improved when assessed by the short physical performance battery (SMD = 0.86, 95% CI = 0.03:1.69, p = 0.046); there was no change in 6-min walk (p = 0.22), timed up-and-go (p = 0.46) or gait speed tests (p = 0.98). The only significant predictor of timed up-and-go performance was age (θ = -0.11, 95% CI = -0.018:-0.005, p = 0.009).

CONCLUSIONS

Assessment and understanding of acute sarcopenia in clinical settings are limited. Incidence varies between clinical conditions, and muscle parameters are affected differently. HGS and muscle function tests may not be sensitive enough to identify acute changes during hospitalisation. Currently, muscle health deterioration may be underdiagnosed impacting recovery, quality of life and overall health following hospitalisation. Further evaluation is necessary to determine the suitability of existing diagnostic criteria of acute sarcopenia. Muscle mass and quality indices might need to become the primary determinants for muscle health assessment in hospitalised populations.

Acute muscle loss in elderly hospitalized patients: Risk factors and adverse clinical outcomes

OBJECTIVE

To assess muscle loss via ultrasound in the elderly and its link to clinical outcomes and risk factors.

METHODS

This retrospective cohort study assessed muscle loss in hospitalized elderly via ultrasound, comparing bilateral anterior thigh thickness (BATT) at admission and after seven days, exploring its relation to hospital-acquired complications (HACs).

RESULTS

In 86 patients (mean age 83.6), a 4.2% BATT decline over a week was seen, with 39.5% losing more than 10%. BATT changes correlated with HACs, with a -10% change as a predictive threshold. Risk factors for severe muscle loss in elderly hospitalized patients include female gender, higher baseline nutrition risk screening 2002 (NRS2002) scores and higher level of coefficient of variation of red blood cell distribution width (RDW-CV).

CONCLUSIONS

Elderly hospitalized patients were at risk of acute muscle loss during their hospital stay. Severe BATT decline during hospitalization in elderly patients was independently associated with HACs.

Nutrition intake, muscle thickness, and recovery outcomes for critically ill patients requiring non-invasive forms of respiratory support: A prospective observational study

BACKGROUND

Use of high-flow nasal cannula (HFNC) and non-invasive ventilation (NIV) in the intensive care unit (ICU) is increasing, yet reporting of nutrition intake, muscle thickness, or recovery outcomes in this population is limited.

OBJECTIVE

The objective of this study was to quantify muscle thickness, nutrition intake, and functional recovery outcomes for patients receiving HFNC/NIV within the ICU.

METHODS

A single-centre, prospective, observational study in adult ICU patients recruited within 48 hrs of commencing HFNC/NIV. Change in quadriceps muscle layer thickness using ultrasound (primary outcome) and 24 hr nutrition intake from study inclusion to day 7 (D7), functional capacity (Barthel Index), and quality of life (EuroQol five-dimension five-level utility index) at D90 were assessed. Data are n (%), mean ± standard deviation or median [interquartile range], are compared using paired sample t-test, and a P value of <0.05 was considered significant.

RESULTS

Primary outcome data were available for n = 28/42: 64 ± 13 y, 61% male, body mass index: 29.1 ± 9.0 kg/m2, and Acute Physiology and Chronic Health Evaluation II score: 17 ± 5. Quadriceps muscle layer thickness reduced from 2.41 ± 0.87 to 2.12 ± 0.73 cm; mean difference: -0.29 cm (95% confidence interval: -0.44, -0.13). Nutrition intake increased from study inclusion to D7: 1735 ± 1283 to 5448 ± 2858 kJ and 17.4 ± 16.6 to 60.9 ± 36.8g protein. Barthel Index was 87 ± 20 at baseline and 91 ± 15 at D90 (out of 100). Quality of life was impaired at D90: 0.64 ± 0.23 (health = 1.0).

CONCLUSION

Critically ill patients receiving HFNC/NIV experienced muscle loss and impaired quality of life.

Acute Skeletal Muscle Wasting is Associated with Prolonged Hospital Stay in Critical Illness with Brain Injury

BACKGROUND

Acute muscle wasting is common in critically ill patients, and this can lead to unfavorable clinical outcomes. The aim of this study was to identify factors associated with muscle wasting and to investigate the association between skeletal muscle wasting and prolonged hospital stay in critically ill patients with acute brain injury.

METHODS

This single-center prospective observational study was conducted in critically ill patients with acute brain injury who stayed in the intensive care unit for at least 1 week. The rectus femoris cross-sectional area was measured via ultrasound at baseline and a week after the first assessment. Univariate and multivariate logistic regression analyses were performed to identify factors that predicted prolonged hospital stay.

RESULTS

A total of 86 patients were included in the study. Their mean age was 49.4 ± 16.9 years, 57% were male, and 46.5% had an admission diagnosis of subarachnoid hemorrhage. The percentage change in the rectus femoris cross-sectional area was 15.8% (95% confidence interval [CI] - 19.8% to - 12.0%; p < 0.001), and 57% of all patients had acute muscle wasting. According to the univariate analysis, there was a significant association between prolonged hospital stay and acute muscle wasting (odds ratio [OR] 3.677; 95% CI 1.487-9.043; p = 0.005), mechanical ventilation status (OR 3.600; 95% CI 1.455-8.904; p = 0.006), and Glasgow Coma Scale score (OR 0.888; 95% CI 0.808-0.976; p = 0.014) at intensive care unit admission. The multivariate analysis demonstrated that acute muscle wasting (OR 3.449; 95% CI 1.344-8.853; p = 0.010) was an independent risk factor for prolonged hospital stay.

CONCLUSIONS

There was considerable muscle wasting in critically ill patients with brain injuries over a 1-week period. Acute muscle wasting was associated with prolonged hospital stay in critically ill patients with acute brain injury.

Methodologies and clinical applications of lower limb muscle ultrasound in critically ill patients: a systematic review and meta-analysis

BACKGROUND

Reduced muscle mass upon admission and development of muscle wasting are frequent in critically ill patients, and linked to unfavorable outcomes. Muscle ultrasound is a promising instrument for evaluating muscle mass. We summarized the findings of lower limb muscle ultrasound values and investigated how the muscle ultrasound parameters of the examination or the patient characteristics influence the results.

METHODS

Systematic review and meta-analysis of studies of lower limb ultrasound critically ill adults. PubMed, CINAHL, Embase, PEDro and Web of Science were searched. PRISMA guidelines were followed, and studies evaluated with the appropriate NIH quality assessment tool. A meta-analysis was conducted to compare the values at admission, short and long follow-up during ICU stay, and the association between baseline values and patient characteristics or ultrasound parameters was investigated with a meta-regression.

RESULTS

Sixty-six studies (3839 patients) were included. The main muscles investigated were rectus femoris cross-sectional area (RF-CSA, n = 33/66), quadriceps muscle layer thickness (n = 32/66), and rectus femoris thickness (n = 19/66). Significant differences were found in the anatomical landmark and ultrasound settings. At ICU admission, RF-CSA ranged from 1.1 [0.73-1.47] to 6.36 [5.45-7.27] cm2 (pooled average 2.83 [2.29-3.37] cm2) with high heterogeneity among studies (I2 = 98.43%). Higher age, higher BMI, more distal landmark and the use of probe compression were associated with lower baseline muscle mass.

CONCLUSIONS

Measurements of muscle mass using ultrasound varied with reference to patient characteristics, patient position, anatomical landmarks used for measurement, and the level of compression applied by the probe; this constrains the external validity of the results and highlights the need for standardization.

STUDY REGISTRATION

PROSPERO CRD42023420376.

Early predictive value of ultrasound measurements of rectus femoris cross-sectional area to diagnose ICU-acquired weakness in patients undergoing invasive mechanical ventilation: a prospective cohort study

BACKGROUND

The diagnosis of ICU-acquired weakness (ICUAW) may be delayed due to the complexity of critically ill patients. This study aimed to investigate the value of ultrasound measurements of rectus femoris cross-sectional area (RFCSA) in predicting ICUAW in patients undergoing invasive mechanical ventilation.

METHODS

This was a prospective cohort study of patients undergoing mechanical ventilation for at least 48 h. RFCSA was measured using ultrasound in patients upon ICU admission and followed until discharge. Using the Medical Research Council score as the gold standard, we evaluated the diagnostic value of ultrasound measurements in predicting ICUAW. Kaplan-Meier curves were constructed to evaluate and compare the length of ICU stay and duration of invasive mechanical ventilation between patients with and without ICUAW.

RESULTS

Among the 76 patients, 34 (44.7%) were diagnosed with ICUAW using the Medical Research Council score as the gold standard. The RFCSA atrophy rate between day 1 and day 3 was significantly higher in the ICUAW group (7.9 ± 2.8% vs. 4.3 ± 2.1%, p < 0.001). By utilizing a cutoff point of 6.9%, we discovered that the RFCSA atrophy rate exhibited excellent diagnostic accuracy in predicting ICUAW, with a sensitivity of 76.5% and specificity of 92.9%. In ICUAW patients diagnosed based on an RFCSA atrophy rate, the proportion of patients with an ICU stay longer than 14 days was 42.9%, which was significantly higher compared to 22.9% in the non-ICUAW group (HR: 1.768; 95% CI 1.128-2.772; p = 0.006). Similarly, the proportion of patients continuing mechanical ventilation at 14 days was 28.6% versus 4.2% between the two groups (HR: 1.988; 95% CI 1.266-3.120; p < 0.001).

CONCLUSION

Ultrasound measurements of RFCSA provide a reliable method for diagnosing ICUAW and indicating prognosis in patients undergoing invasive mechanical ventilation.

β-hydroxybutyrate exposure restores mitochondrial function in skeletal muscle satellite cells of critically ill patients

BACKGROUND & AIM

Dysfunction of skeletal muscle satellite cells might impair muscle regeneration and prolong ICU-acquired weakness, a condition associated with disability and delayed death. This study aimed to elucidate the distinct metabolic effects of critical illness and β-OH-butyrate on satellite cells isolated from these patients.

METHODS

Satellite cells were extracted from vastus lateralis muscle biopsies of patients with ICU-acquired weakness (n = 10) and control group of healthy volunteers or patients undergoing elective hip replacement surgery (n = 10). The cells were exposed to standard culture media supplemented with β-OH-butyrate to assess its influence on cell proliferation by ELISA, mitochondrial functions by extracellular flux analysis, electron transport chain complexes by high resolution respirometry, and ROS production by confocal microscopy.

RESULTS

Critical illness led to a decline in maximal respiratory capacity, ATP production and glycolytic capacity and increased ROS production in ICU patients' cells. Notably, the function of complex II was impaired due to critical illness but restored to normal levels upon exposure to β-OH-butyrate. While β-OH-butyrate significantly reduced ROS production in both control and ICU groups, it had no significant impact on global mitochondrial functions.

CONCLUSION

Critical illness induces measurable bioenergetic dysfunction of skeletal muscle satellite cells. β-OH-butyrate displayed a potential in rectifying complex II dysfunction caused by critical illness and this warrants further exploration.

An Observational Study of Nutritional Assessment, Prescription, Practices, and Its Outcome among Critically Ill Patients Admitted to an Intensive Care Unit

Aim and background

Optimal feeding strategy for critically ill patients of intensive care unit (ICU) is often a matter of debate as patients admitted to ICU are highly catabolic and reduction in muscle mass is very common. We aimed at early achievement of nutritional goals in preventing skeletal muscle breakdown and improving clinical outcomes among critically ill patients with high risk of malnutrition.

Materials and methods

Nutrition risk in the critically ill (mNUTRIC) Score was used to identify the risk of malnutrition within 24 hours of admission. Quadriceps muscle mass index was measured within 24 hours of admission to ICU and repeated on 7th day. Enteral feeding was monitored by the nutrition expert as part of routine patient care and clinical outcomes were monitored.

Results

A total of 287 patients admitted in ICU were screened for malnutrition and 60 (20.9%) of them had high score (>5). There was no statistically significant reduction in the quadriceps muscle mass index (p < 0.05) (t = 0.601) measured within 24 hours of admission and on the 7th day of ICU stay, signifying that the nutritional prescription and monitoring may be useful in preserving the muscle mass. This study did not find statistically significant association between the high mNUTRIC score on admission and the clinical outcomes, such as 28 days mortality, incidence of pressure ulcers, length of ICU stay, and hospital-acquired infection (p > 0.05).

Conclusion

Early initiation and maintenance of enteral nutrition is essential for meeting target calories and protein requirements. It may help to preserve muscle mass in critically ill patients who are otherwise at high risk of malnutrition.

How to cite this article

Sharon T, Nayak SG, Shanbhag V, Hebbar S. An Observational Study of Nutritional Assessment, Prescription, Practices, and Its Outcome among Critically Ill Patients Admitted to an Intensive Care Unit. Indian J Crit Care Med 2024;28(4):364-368.

Prolonged intensive care: muscular functional, and nutritional insights from the COVID-19 pandemic

During the coronavirus disease 2019 (COVID-19) pandemic, clinical staff learned how to manage patients enduring extended stays in an intensive care unit (ICU). COVID-19 patients requiring critical care in an ICU face a high risk of experiencing prolonged intensive care (PIC). The use of invasive mechanical ventilation in individuals with severe acute respiratory distress syndrome can cause numerous complications that influence both short-term and long-term morbidity and mortality. Those risks underscore the importance of proactively addressing functional complications. Mitigating secondary complications unrelated to the primary pathology of admission is imperative in minimizing the risk of PIC. Therefore, incorporating strategies to do that into daily ICU practice for both COVID-19 patients and those critically ill from other conditions is significantly important.

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.

Combined ultrasound of m. quadriceps and diaphragm to determine the occurrence of sarcopenia and prolonged ventilation in a COVID-19 ICU cohort: The COVID-SARCUS trial

OBJECTIVE

The aim of this study was to determine the development of sarcopenia in a COVID-19 intensive care unit population by sequential quadriceps and diaphragm ultrasound and its relationship with hospital outcomes.

METHODS

We assessed muscle thickness, cross-sectional area, fascicle length, pennation angle, and echo intensity within 48 h after intubation, at days 5 and 10 and at discharge from the intensive care unit in 30 critically ill patients with confirmed COVID-19.

RESULTS

A different evolution of muscle thickness of the diaphragm and m. rectus femoris was observed; the changes between the two muscles were not correlated (Pearson's χ2 3.91, P = 0.419). The difference in muscle thickness was linked to the outcome for both m. rectus femoris and diaphragm, with the best survival seen in the group with stable muscle thickness. The greatest loss of muscle thickness occurred between days 5 and 10. The echo intensity was higher in the patients with increased muscle thickness, who also had a worse prognosis. There was a correlation between cross-sectional area on day 5 and handgrip strength (r = 0.290, P = 0.010). Only 31% of patients were able to return to their preadmission residence without any additional rehabilitation.

CONCLUSIONS

Muscle atrophy and decline in muscle strength appear in the earliest stages after admission to the intensive care unit and are related to functional outcome.

Ultrasound-based evaluation of loss of lean mass in patients with burns: A prospective longitudinal study

OBJECTIVES

To evaluate the loss of lean mass in patients with burns using ultrasonography of the quadriceps muscle of the thigh.

METHODS

A prospective longitudinal study was conducted using ultrasound of the quadriceps muscle of the thigh to assess the change in thickness in millimeters on days 1, 3 and 7 after study enrollment in 45 patients with burns who were admitted to a burn center (BTC) of a university hospital between April 2020 and September 2021. Patients burns on the thighs, which made it difficult to undertake examinations, were excluded. Depending on where they were admitted, patients were divided into ward and intensive care unit (ICU) patients. ICU patients were considered to have more severe injuries. The general data collected included age, sex, weight, height, area of body surface burn, burn degree and etiology, and airway injury. The data collected for all patients during hospitalization at the BTC were as follows: existence of chronic illness, requirement for mechanical ventilation, Simplified Acute Physiology Score 3 (SAPS 3) and Sequential Organ Failure Assessment (SOFA) on the first day of hospitalization in an intensive care bed in the burn treatment unit (BTU), health-related infection, feeding route, length of hospital stay, and time spent in the BTU.

RESULTS

Loss of muscle thickness was observed in all patients between days 1 and 7. The median thickness for all patients on day 1 was 24.50 mm (ITQ 21.22-30.85) and on day 7 it was 18.80 (ITQ 16.07-23.62), with P = 0.0001. The variation in thigh quadricep muscle thickness between day 1 and day 3, a median of - 2.80 mm (ITQ - 3.52-2.02) was obtained for patients on the ward and - 2.50 mm (ITQ - 3.92 to - 1.47) for ICU patients. Between day 3 and day 7, the variation was - 2.55 mm (ITQ - 4.55 to - 1.25) for ward patients and - 2.10 mm (ITQ - 3.12 to - 1.15) for ICU patients. The median thickness variation assessed between day 1 and day 7 was - 4.95 mm (ITQ - 8.25 to - 3.70) for patients on the ward and - 4.40 mm (ITQ - 7, 35 to - 2.90) for ICU patients. A correlation was observed between the variation in muscle thickness in the interval between day 1 to day 3 and age (P = 0.035).

CONCLUSIONS

Muscle loss occurred early and rapidly within the first seven days of hospitalization, reflecting the impact of burn injury on nutritional risk. An association was observed between muscle thickness loss and age, but no association was observed with the extent of burn, length of hospital stay, occurrence of health-related infections or mortality. These findings suggest the importance of monitoring muscle loss in these patients in planning nutritional therapy, early mobilization, and prevention of complications.

Ultrasound assessment of muscle mass and correlation with clinical outcomes in critically ill patients: a prospective observational study

PURPOSE

Muscular atrophy implies structural and functional alterations related to muscular force production and movement. This condition has been reported to be the main reason for generalized muscle weakness; it reflects the severity of the disease and can have a profound impact on short- and long-term clinical outcomes. The purpose of this study was to determine whether muscle atrophy ultrasound parameters early predict muscle weakness, morbidity, or 28-days mortality.

METHODS

This was a prospective, observational single center cohort study. Ultrasound was used to determine the cross-sectional area and muscle thickness of the rectus femoris on the first and third day of ICU stay. The main outcome was the incidence of significant muscle atrophy (≥ 10%).

RESULTS

Ultrasound measurements were made in 31 patients, 58% (18/31) of which showed significant muscle atrophy. The relative loss of muscle mass per day was 1.78 at 5% per day. The presence of muscle atrophy presents increased risk for limb muscle weakness and handgrip weakness. The 28-days mortality rate was similar in both subgroups.

CONCLUSION

The presence of muscle atrophy presents an increased clinical risk for the development of limb ICUAW and handgrip, although these observations were not statistically significant. The results could be used to plan future studies on this topic.

Update on Lean Body Mass Diagnostic Assessment in Critical Illness

Acute critical illnesses can alter vital functions with profound biological, biochemical, metabolic, and functional modifications. Despite etiology, patient's nutritional status is pivotal to guide metabolic support. The assessment of nutritional status remains complex and not completely elucidated. Loss of lean body mass is a clear marker of malnutrition; however, the question of how to investigate it still remains unanswered. Several tools have been implemented to measure lean body mass, including a computed tomography scan, ultrasound, and bioelectrical impedance analysis, although such methods unfortunately require validation. A lack of uniform bedside measurement tools could impact the nutrition outcome. Metabolic assessment, nutritional status, and nutritional risk have a pivotal role in critical care. Therefore, knowledge about the methods used to assess lean body mass in critical illnesses is increasingly required. The aim of the present review is to update the scientific evidence regarding lean body mass diagnostic assessment in critical illness to provide the diagnostic key points for metabolic and nutritional support.

Reproducibility and feasibility of a handheld ultrasound device compared to a standard ultrasound machine in muscle thickness measurements

Objective

To test the feasibility and reproducibility of a handheld ultrasound device (HUD) compared to a standard ultrasound machine for muscle thickness measurements in healthy participants.

Methods

A prospective cross-sectional study was designed where two novice operators tested the thickness of the vastus lateralis, rectus femoris, and vastus intermedius muscles on recruited asymptomatic participants with no history of muscle diseases. The anterior-posterior thickness of each muscle was measured three times per operator to evaluate intra-operator reproducibility and using two machines to evaluate inter-system reproducibility. Scanning started using the HUD followed by the standard system. Intraclass correlation coefficients (ICC) and simple linear regression were used to test for reproducibility and proportional bias respectively.

Results

A total of 33 male participants volunteered to take part in this study with a mean age of 22.7 years (6.8). Intra-operator reproducibility was almost perfect for both operators on both machines (ICC > 0.80). The measurements difference percentage between the machines ranged from 1.8% to 6.6% and inter-system reproducibility ICC ranged from 0.815 to 0.927 showing excellent reproducibility. Inter-operator reproducibility was poor to moderate on both machines (ICC: 0.522-0.849). Regression analysis showed no proportional bias in the measurements. All measurements were completed successfully using the HUD.

Conclusion

The HUD demonstrated excellent accuracy compared to the standard ultrasound machine for measuring thigh muscle thickness.

The rate and assessment of muscle wasting during critical illness: a systematic review and meta-analysis

BACKGROUND

Patients with critical illness can lose more than 15% of muscle mass in one week, and this can have long-term detrimental effects. However, there is currently no synthesis of the data of intensive care unit (ICU) muscle wasting studies, so the true mean rate of muscle loss across all studies is unknown. The aim of this project was therefore to systematically synthetise data on the rate of muscle loss and to identify the methods used to measure muscle size and to synthetise data on the prevalence of ICU-acquired weakness in critically ill patients.

METHODS

We conducted a systematic literature search of MEDLINE, PubMed, AMED, BNI, CINAHL, and EMCARE until January 2022 (International Prospective Register of Systematic Reviews [PROSPERO] registration: CRD420222989540. We included studies with at least 20 adult critically ill patients where the investigators measured a muscle mass-related variable at two time points during the ICU stay. We followed Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines and assessed the study quality using the Newcastle-Ottawa Scale.

RESULTS

Fifty-two studies that included 3251 patients fulfilled the selection criteria. These studies investigated the rate of muscle wasting in 1773 (55%) patients and assessed ICU-acquired muscle weakness in 1478 (45%) patients. The methods used to assess muscle mass were ultrasound in 85% (n = 28/33) of the studies and computed tomography in the rest 15% (n = 5/33). During the first week of critical illness, patients lost every day -1.75% (95% CI -2.05, -1.45) of their rectus femoris thickness or -2.10% (95% CI -3.17, -1.02) of rectus femoris cross-sectional area. The overall prevalence of ICU-acquired weakness was 48% (95% CI 39%, 56%).

CONCLUSION

On average, critically ill patients lose nearly 2% of skeletal muscle per day during the first week of ICU admission.

Reliability and Validity of Quadriceps Muscle Thickness Measurements in Ultrasonography: A Comparison with Muscle Mass and Strength

Objectives

Measurement of skeletal muscle using ultrasonography (US) has received considerable attention as an alternative method of muscle assessment. However, intra- and inter-rater reliability remains controversial. Furthermore, there is no consensus regarding the relationship between muscle assessment using US and muscle mass or physical assessment. We aimed to verify the validity and reliability of muscle measurements using US and its relationships with muscle strength and physical assessment.

Methods

The 22 participants were all healthy men. Quadriceps muscle thickness was measured by US by three different raters. Intraclass correlation coefficient (ICC) was used to assess inter- and intra-rater reliability. The maximum isokinetic strength of the quadriceps and handgrip strength were used as measures of lower and upper muscle strength, respectively. Leg muscle mass was assessed using the leg skeletal muscle index (SMI), measured by body impedance analysis, and calf circumference.

Results

The intra-rater reliability was excellent which the ICC(1,1) ranges 0.957-0.993, and ICC(1,3) ranges 0.985-0.998. For inter-rater reliability, the values of 0.904 for ICC(2,1) and 0.966 for ICC(2,3) indicated excellent reliability. Leg SMI was significantly correlated with quadriceps thickness (r=0.36). Maximum isokinetic strength and handgrip strength showed weak but statistically significant correlations with quadriceps thickness (r=0.20, r=0.30, respectively). The correlation between quadriceps thickness and calf circumference was not statistically significant.

Conclusions

Quadriceps muscle assessment using US is a valid and reliable technique for healthy individuals. Quadriceps muscle thickness was significantly positively correlated with upper and lower muscle strength and leg SMI. Muscle thickness assessment could replace full body muscle assessment in clinical settings.

The current use of ultrasound to measure skeletal muscle and its ability to predict clinical outcomes: a systematic review

Quantification and monitoring of lean body mass is an important component of nutrition assessment to determine nutrition status and muscle loss. The negative impact of reduced muscle mass and muscle function is increasingly evident across acute and chronic disease states but is particularly pronounced in patients with cancer. Ultrasound is emerging as a promising tool to directly measure skeletal muscle mass and quality. Unlike other ionizing imaging techniques, ultrasound can be used repeatedly at the bedside and may compliment nutritional risk assessment. This review aims to describe the current use of skeletal muscle ultrasound (SMUS) to measure muscle mass and quality in patients with acute and chronic clinical conditions and its ability to predict functional capacity, severity of malnutrition, hospital admission, and survival. Databases were searched from their inception to August 2021 for full-text articles in English. Relevant articles were included if SMUS was investigated in acute or chronic clinical contexts and correlated with a defined clinical outcome measure. Data were synthesized for narrative review due to heterogeneity between studies. This review analysed 37 studies (3100 patients), which met the inclusion criteria. Most studies (n = 22) were conducted in critical care. The clinical outcomes investigated included functional status at discharge (intensive care unit-acquired weakness), nutritional status, and length of stay. SMUS was also utilized in chronic conditions such as chronic obstructive pulmonary disease, chronic heart failure, and chronic renal failure to predict hospital readmission and disease severity. Only two studies investigated the use of SMUS in patients with cancer. Of the 37 studies, 28 (76%) found that SMUS (cross-sectional area, muscle thickness, and echointensity) showed significant associations with functional capacity, length of stay, readmission, and survival. There was significant heterogeneity in terms of ultrasound technique and outcome measurement across the included studies. This review highlights that SMUS continues to gain momentum as a potential tool for skeletal muscle assessment and predicting clinically important outcomes. Further work is required to standardize the technique in nutritionally vulnerable patients, such as those with cancer, before SMUS can be widely adopted as a bedside prognostic tool.

Association between skeletal muscle changes, anthropometric measurements, and clinical outcomes in critically ill trauma and surgical patients: A prospective observational study

BACKGROUND

Acute skeletal muscle wasting may predict clinical outcomes in critically ill patients. This study aimed to assess acute muscle loss, changes in anthropometric measurements, and the relationship between muscle loss and clinical outcomes in critically ill trauma and surgical patients.

METHODS

This single-center, prospective observational study was conducted in critically ill trauma and surgical patients who were expected to stay in the intensive care unit (ICU) for at least 7 days. Rectus femoris cross-sectional area muscle measurements were performed by bedside ultrasound, and anthropometric measurements were obtained at baseline and 7 days after the first assessment. Length of mechanical ventilation, ICU and hospital stay, and mortality were recorded.

RESULTS

Thirty-five patients with a mean age of 49.6 ± 18.6 years and 74.1% male were enrolled. The rectus femoris cross-sectional area, mid-arm circumference, and calf circumference were reduced at second assessment from baseline (P < 0.05). In univariate analysis, muscle loss and changes in anthropometric measurements were not associated with 90-day mortality (P > 0.05).

CONCLUSION

Muscle loss in critical trauma and surgical patients occurred rapidly during the first week of critical illness. Rectus femoris muscle cross-sectional area assessment can be used to detect skeletal muscle changes in critically ill patients. Further investigations on the skeletal muscle changes and clinical outcomes need to be conducted.