Metabolic aspects of muscle wasting during critical illness

Pediatric Acute Respiratory Distress Syndrome Severity and Health-Related Quality of Life Outcomes: Single-Center Retrospective Cohort, 2011-2017

OBJECTIVES

To determine factors associated with health-related quality of life (HRQL) decline among pediatric acute respiratory distress syndrome (PARDS) survivors.

DESIGN

Retrospective cohort study.

SETTING

Academic children's hospital.

PATIENTS

Three hundred fifteen children 1 month to 18 years old with an unplanned PICU admission from December 2011 to February 2017 enrolled in the hospital's Outcomes Assessment Program.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Pre-admission baseline and median 6-week post-discharge HRQL were assessed using the Pediatric Quality of Life Inventory or the Functional Status II-R. Patients meeting retrospectively applied Second Pediatric Acute Lung Injury Consensus Conference criteria for PARDS were identified, and PARDS severity was classified using binary (mild/moderate, severe) and trichotomous (mild, moderate, severe) categorization for noninvasive ventilation and invasive mechanical ventilation (IMV). PARDS occurred in 41 of 315 children (13.0%). Clinically important HRQL decline (≥ 4.5 points) occurred in 17 of 41 patients (41.5%) with PARDS and 64 of 274 without PARDS (23.4%). On multivariable generalized linear regression adjusted for age, baseline Pediatric Overall Performance Category, maximum nonrespiratory Pediatric Logistic Organ Dysfunction score, diagnosis, length of stay, and time to follow-up, PARDS was associated with HRQL decline (adjusted relative risk [aRR], 1.70; 95% CI, 1.03-2.77). Four-hour and maximum PARDS severity were the only factors associated with HRQL decline. HRQL decline occurred in five of 18 patients with mild PARDS at 4 hours, five of 13 with moderate PARDS (aRR 2.35 vs. no PARDS [95% CI, 1.01-5.50]), and seven of ten with severe PARDS (aRR 2.56 vs. no PARDS [95% CI, 1.45-4.53]). The area under the receiver operating characteristic curve for discrimination of HRQL decline for IMV patients was 0.79 (95% CI, 0.66-0.91) for binary and 0.80 (95% CI, 0.69-0.93) for trichotomous severity categorization.

CONCLUSIONS

HRQL decline is common among children surviving PARDS, and risk of decline is associated with PARDS severity. HRQL decline from baseline may be an efficient and clinically meaningful endpoint to incorporate into PARDS clinical trials.

Nutrition determinants of acute skeletal muscle loss in critically ill patients: A prospective observational cohort study

BACKGROUND

Skeletal muscle loss is associated with adverse outcomes in critically ill patients and risk factors of acute skeletal muscle loss are not well described. This study aims to determine the factors associated with acute skeletal muscle loss in critically ill patients.

METHODS

This prospective observational cohort study was conducted with patients who were expected to stay in the intensive care unit (ICU) for at least a week. Rectus femoris cross-sectional area (RFCSA) measurements were performed within 48 h of ICU admission and on study day 7. The percentage change in RFCSA and variables associated with this change were evaluated by univariate and multivariate regression analysis.

RESULTS

Over a 12-month period, 518 patients were assessed for eligibility and 44 critically ill patients with a mean age of 59.3 ± 10.9 years were enrolled; 52.3% of them were female. There were significant reductions in RFCSA (16.8 ± 16.5%; P < 0.001). The mean amounts of protein and energy consumed compared with those prescribed were 67.0 ± 28.8% and 71.5 ± 38.3%, respectively. Multivariate regression analysis revealed that frailty was independently associated with acute skeletal muscle loss after adjusting for confounding factors in our cohort of patients.

CONCLUSION

Frailty status before ICU admission is associated with acute skeletal muscle loss and may be important for identifying critically ill patients at high risk of muscle wasting.

Longitudinal associations of plasma amino acid levels with recovery from malarial coma

Background

Disordered amino acid metabolism is observed in cerebral malaria (CM). We sought to determine whether abnormal amino acid concentrations were associated with level of consciousness in children recovering from coma. We quantified 21 amino acids and coma scores longitudinally and analyzed data for associations.

Methods

In a prospective observational study, we enrolled 42 children with CM. We measured amino acid levels at entry and at frequent intervals thereafter and assessed consciousness by Blantyre Coma Scores (BCS). Thirty-six healthy children served as controls for in-country normal amino acid ranges. We employed logistic regression using a generalized linear mixed-effects model to assess associations between out-of-range amino acid levels and BCS.

Results

At entry 16/21 amino acid levels were out-of-range. Longitudinal analysis revealed 10/21 out-of-range amino acids were significantly associated with BCS. Elevated phenylalanine levels showed the highest association with low BCS. This finding held when out-of-normal-range data were analyzed at each sampling time.

Discussion

We provide longitudinal data for associations between abnormal amino acid levels and recovery from CM. Of 10 amino acids significantly associated with BCS, we propose that elevated phenylalanine may be a surrogate for impaired clearance of ether lipid mediators of inflammation contributing to CM pathogenesis.

Nutrition delivery and the relationship with changes in muscle mass in adult patients receiving extracorporeal membrane oxygenation: A retrospective observational study

BACKGROUND

Adverse changes in muscle health (size and quality) are common in patients receiving extracorporeal membrane oxygenation (ECMO). Nutrition delivery may attenuate such changes, yet the relationship with muscle health remains poorly understood. This study explored the association between energy and protein delivery and changes in muscle health measured using ultrasound from baseline to day 10 and 20 in patients receiving ECMO.

METHODS

A secondary analysis of data from a prospective study quantifying changes in muscle health using ultrasound in adults receiving ECMO was completed. Patients were eligible for inclusion if they were prescribed artificial nutrition within 3 days of enrolment and had >1 ultrasound measurement. The primary outcome was the association between protein delivery (grams delivered and percentage of targets received) and change in rectus femoris cross-sectional area (RF-CSA) till day 20. Secondary outcomes were the association between energy and protein delivery and change in RF-CSA till day 10, RF-echogenicity, and quadriceps muscle layer thickness to day 10 and 20. Associations were assessed using Spearman's rank correlation.

RESULTS

Twenty-three patients (age: 48 [standard deviation {SD}: 14], 44% male) were included. Mean energy and protein delivery were 1633 kcal (SD: 374 kcal) and 70 g (SD: 17 g) equating to 79% (SD: 19%) of energy and 73% (SD: 17%) of protein targets. No association was observed between protein delivery (r = 0.167; p = 0.495) or the percentage of targets received (r = 0.096; p = 0.694) and change in RF-CSA till day 20. No other significant associations were found between energy or protein delivery and change in RF-CSA, echogenicity, or quadriceps muscle layer thickness at any time point.

CONCLUSIONS

This exploratory study observed no association between nutrition delivery and changes in muscle health measured using ultrasound in patients receiving ECMO. Larger prospective studies are required to investigate the association between nutrition delivery and changes in muscle health in patients receiving ECMO.

Association of tissue oxygen saturation levels with skeletal muscle injury in the critically ill

This study aimed to investigate the association between the level of tissue oxygen saturation (StO2) and quadriceps/skeletal muscle dysfunction, measured using the Medical Research Council (MRC) scale and ultrasonography, in critically ill patients. Thirty-four patients hospitalized at the Critical Care Medicine Center of Kindai University Hospital, between January 2022 and March 2023, were enrolled in this study. The StO2 of the quadriceps muscle was measured via near-infrared spectroscopy. Muscle atrophy was measured by the thickness, cross-sectional area (CSA), and echo intensity of the rectus femoris (RF). These values were evaluated every alternate day until 13 days after admission or until discharge, whichever occurred first. Muscle weakness was assessed using the sum score of the MRC scale (MRC-SS), with the patient sitting at bedside. The mean age of the patients was 67.3 ± 15.3 years, and 20 (59%) were men. Seven patients (21%) were admitted for trauma, and 27 (79%) were admitted for medical emergencies or others. The mean score for the MRC-SS was 51.0 ± 7.9 points. RF thickness and CSA significantly decreased after day 7 (p < 0.05). There were no significant changes in StO2 levels during hospitalization. However, there were positive correlations between the nadir StO2 during hospitalization and MRC-SS, and changes in RF thickness and CSA at discharge (r = 0.41, p = 0.03; r = 0.37, p = 0.03; and r = 0.35, p = 0.05, respectively). StO2 in the quadriceps muscle may be useful for predicting muscle atrophy and dysfunction in patients with critical illnesses.

The impact of high versus standard enteral protein provision on functional recovery following intensive care admission: Protocol for a pre-planned secondary Bayesian analysis of the PRECISe trial

BACKGROUND

The PRECISe trial is a pragmatic, multicenter randomized controlled trial that evaluates the effect of high versus standard enteral protein provision on functional recovery in adult, mechanically ventilated critically ill patients. The current protocol presents the rationale and analysis plan for an evaluation of the primary and secondary outcomes under the Bayesian framework, with an emphasis on clinically important effect sizes.

METHODS

This protocol was drafted in agreement with the ROBUST-statement, and is submitted for publication before database lock and primary data analysis. The primary outcome is health-related quality of life as measured by the EQ-5D-5L health utility score and is longitudinally assessed. Secondary outcomes comprise the 6-min walking test and handgrip strength over the entire follow-up period (longitudinal analyses), and 60-day mortality, duration of mechanical ventilation, and EQ-5D-5L health utility scores at 30, 90 and 180 days (cross-sectional). All analyses will primarily be performed under weakly informative priors. When available, informative priors elicited from contemporary literature will also be incorporated under alternative scenarios. In all other cases, objectively formulated skeptical and enthusiastic priors will be defined to assess the robustness of our results. Relevant identified subgroups were: patients with acute kidney injury, severe multi-organ failure and patients with or without sepsis. Results will be presented as absolute risk differences, mean differences, and odds ratios, with accompanying 95% credible intervals. Posterior probabilities will be estimated for clinically important benefit and harm.

DISCUSSION

The proposed secondary, pre-planned Bayesian analysis of the PRECISe trial will provide additional information on the effects of high protein on functional and clinical outcomes in critically ill patients, such as probabilistic interpretation, probabilities of clinically important effect sizes, and the integration of prior evidence. As such, it will complement the interpretation of the primary outcome as well as several secondary and subgroup analyses.

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.

A Narrative Review: Analysis of Supplemental Parenteral Nutrition in Adults at the End of Life

"End of life" is a stage defined by the existence of an irreversible prognosis that ends with a person's death. One of the aspects of interest regarding end of life focuses on parenteral nutrition, which is usually administered in order to avoid malnutrition and associated complications. However, parenteral nutrition can be adapted to specific circumstances and evolve in its functionality through supplementation with certain nutrients that can have a beneficial effect. This narrative review aims to carry out a situation analysis of the role that could be adopted by supplemental parenteral nutrition in attenuating alterations typical of end of life and potential improvement in quality of life.

Ultrasonographic Features of Muscular Weakness and Muscle Wasting in Critically Ill Patients

Muscle wasting begins as soon as in the first week of one's ICU stay and patients with multi-organ failure lose more muscle mass and suffer worse functional impairment as a consequence. Muscle wasting and weakness are mainly characterized by a generalized, bilateral lower limb weakness. However, the impairment of the respiratory and/or oropharyngeal muscles can also be observed with important consequences for one's ability to swallow and cough. Muscle wasting represents the result of the disequilibrium between breakdown and synthesis, with increased protein degradation relative to protein synthesis. It is worth noting that the resulting functional disability can last up to 5 years after discharge, and it has been estimated that up to 50% of patients are not able to return to work during the first year after ICU discharge. In recent years, ultrasound has played an increasing role in the evaluation of muscle. Indeed, ultrasound allows an objective evaluation of the cross-sectional area, the thickness of the muscle, and the echogenicity of the muscle. Furthermore, ultrasound can also estimate the thickening fraction of muscle. The objective of this review is to analyze the current understanding of the pathophysiology of acute skeletal muscle wasting and to describe the ultrasonographic features of normal muscle and muscle weakness.

Predicting functional and quality-of-life outcomes following pediatric sepsis: performance of PRISM-III and PELOD-2

BACKGROUND

Illness severity scores predict mortality following pediatric critical illness. Given declining PICU mortality, we assessed the ability of the Pediatric Risk of Mortality-III (PRISM) and Pediatric Logistic Organ Dysfunction-2 (PELOD) scores to predict morbidity outcomes.

METHODS

Among 359 survivors <18 years in the Life After Pediatric Sepsis Evaluation multicenter prospective cohort study, we assessed functional morbidity at hospital discharge (Functional Status Scale increase ≥3 points from baseline) and health-related quality of life (HRQL; Pediatric Quality of Life Inventory or Functional Status II-R) deterioration >25% from baseline at 1, 3, 6, and 12 months post-admission. We determined discrimination of admission PRISM and admission, maximum, and cumulative 28-day PELOD with functional and HRQL morbidity at each timepoint.

RESULTS

Cumulative PELOD provided the best discrimination of discharge functional morbidity (area under the receive operating characteristics curve [AUROC] 0.81, 95% CI 0.76-0.87) and 3-month HRQL deterioration (AUROC 0.71, 95% CI 0.61-0.81). Prediction was inferior for admission PRISM and PELOD and for 6- and 12-month HRQL assessments.

CONCLUSIONS

Illness severity scores have a good prediction of early functional morbidity but a more limited ability to predict longer-term HRQL. Identification of factors beyond illness severity that contribute to HRQL outcomes may offer opportunities for intervention to improve outcomes.

IMPACT

Illness severity scores are commonly used for mortality prediction and risk stratification in pediatric critical care research, quality improvement, and resource allocation algorithms. Prediction of morbidity rather than mortality may be beneficial given declining pediatric intensive care unit mortality. The PRISM and PELOD scores have moderate to good ability to predict new functional morbidity at hospital discharge following pediatric septic shock but limited ability to predict health-related quality of life outcomes in the year following PICU admission. Further research is needed to identify additional factors beyond illness severity that may impact post-discharge health-related quality of life.

Quality indicators in prolonged hemodialysis with regional citrate anticoagulation with the genius system: retrospective cohort of critical patients with acute kidney injury

BACKGROUND

Prolonged hemodialysis (HD) is performed from 6 to 12 h and can last up to 24 h. To prevent system clotting some studies suggest that Regional Citrate Anticoagulation (RCA) use reduces bleeding rates relative to systemic heparin. However, there may be difficulties in the patient's clinical management and completing the prescribed HD with Genius system using RCA.

OBJECTIVE

To analyze safety Quality Indicators (IQs) and follow up on prolonged HD with 4% sodium citrate solution in a Genius® hybrid system.

METHODS

This is a retrospective cohort conducted in an intensive care unit.

RESULTS

53 random sessions of prolonged HD with 4% sodium citrate solution of critically ill patients with AKI assessed. Evaluated safety indicators were dysnatremia and metabolic alkalosis, observed in 15% and 9.4% of the sessions, respectively. Indicators of effectiveness were system clotting which occurred in 17.3%, and the minimum completion of the prescribed HD time, which was 75.5%.

CONCLUSION

The assessment of the indicators showed that the use of RCA with a 4% sodium citrate solution in prolonged HD with the Genius system in critically ill patients with AKI can be performed in a simple, safe, and effective way.

Predictors of acute muscle loss in the intensive care unit: A secondary analysis of an in-bed cycling trial for critically ill patients

PURPOSE

The purpose of this study was to assist clinicians to identify critically ill patients at greatest risk of acute muscle loss and to analyse the associations between protein intake and exercise on acute muscle loss.

MATERIALS AND METHODS

Secondary analysis of a single-centre randomised clinical trial of in-bed cycling using a mixed effects model was undertaken to examine the association between key variables and rectus femoris cross-sectional area (RFCSA). Groups were combined, and key variables for the cohort were modified Nutrition Risk in the Critically Ill (mNUTRIC) scores within the first days following intensive care unit admission, longitudinal RFCSA measurements, percent of daily recommended protein intake, and group allocation (usual care, in-bed cycling). RFCSA ultrasound measurements were taken at baseline and days 3, 7, and 10 to quantify acute muscle loss. All patients received usual care nutritional intake while in the intensive care unit. Patients allocated to the cycling group commenced in-bed cycling once safety criteria were met.

RESULTS

Analysis included all 72 participants, of which 69% were male, with a mean (standard deviation) age of 56 (17) years. Patients received a mean (standard deviation) of 59% (26%) of the minimum protein dose recommended for critically ill patients. Mixed-effects model results indicated that patients with higher mNUTRIC scores experienced greater RFCSA loss (estimate = -0.41; 95% confidence interval [CI] = -0.59 to -0.23). RFCSA did not share a statistically significant association with cycling group allocation (estimate = -0.59, 95% CI = -1.53 to 0.34), the percentage of protein requirements received (estimate = -0.48; 95% CI = -1.16 to 0.19), or a combination of cycling group allocation and higher protein intake (estimate = 0.33, 95% CI = -0.76 to 1.43).

CONCLUSIONS AND RELEVANCE

We found that a higher mNUTRIC score was associated with greater muscle loss, but we did not observe a relationship between combined protein delivery and in-bed cycling and muscle loss. The low protein doses achieved may have impacted the potential for exercise or nutrition strategies to reduce acute muscle loss.

TRIAL REGISTRATION

Australian and New Zealand Clinical Trials Registry (ACTRN 12616000948493).

Beta-hydroxy-beta-methylbutyrate supplementation and functional outcomes in multitrauma patients: A pilot randomized controlled trial

BACKGROUND

Beta-hydroxy-beta-methylbutyrate (HMB) is a nutrition supplement that may attenuate muscle wasting from critical illness. This trial aimed to determine feasibility of administering a blinded nutrition supplement in the intensive care unit (ICU) and continuing it after ICU discharge.

METHODS

Single-center, parallel-group, blinded, placebo-controlled, randomized feasibility trial. After traumatic injury necessitating admission to ICU, participants were randomized to receive an enteral study supplement of 3 g of HMB (intervention) or placebo daily for 28 days or until hospital discharge. Primary outcome was feasibility of administering the study supplement, quantified as protocol adherence. Secondary outcomes included change in quadriceps muscle thickness, measured weekly until day 28 or hospital discharge by using ultrasound and analyzed by using a linear mixed model.

RESULTS

Fifty randomized participants (intervention, n = 26; placebo, n = 24) showed comparable baseline characteristics. Participants received 862 (84.3%) of the 1022 prescribed supplements during hospitalization with 543 (62.8%) delivered via an enteral feeding tube. The median (IQR) number of study supplements successfully administered per participant was 19.5 (13.0-24.0) in the intervention group and 16.5 (8.5-23.5) in the placebo group. Marked loss of quadriceps muscle thickness occurred in both groups, with the point estimate favoring attenuated muscle loss with the intervention, albeit with wide CIs (mean intervention difference after 28 days, 0.26 cm [95% CI, -0.13 to 0.64]).

CONCLUSION

A blinded, placebo-controlled, randomized clinical trial of daily enteral HMB supplementation for up to 28 days in hospital is feasible. Any effect of HMB supplementation to attenuate muscle wasting after traumatic injury remains uncertain.

Serum metabolomics analysis for quantification of muscle loss in critically ill patients: An explorative study

BACKGROUND

During Intensive Care Unit (ICU) admission, patients demonstrate up to 15% muscle loss per week, contributing to neuromuscular weakness, complicating recovery and delaying return to daily life. Biomarkers for muscle loss could aid in early detection of patients at risk and help guide resources to mitigate muscle loss, e.g. physical therapy and protein supplementation.

AIMS

To explore serum biomarkers for muscle mass and muscle loss in ICU patients using a metabolomics approach.

METHODS

Mechanically ventilated patients with an unplanned ICU admission between June and December 2021 were prospectively studied. The cross-sectional area of the rectus femoris muscle was assessed using ultrasound (RFcsa) and 188 serum metabolites were assessed using the Biocrates™ AbsoluteIDQ p180 kit for targeted metabolomics. Patients were eligible for analysis when a serum sample drawn within 5 days of ICU admission and at least 1 RFcsa were available. In patients with sequential RFcsa measurements, muscle loss was defined as the negative slope of the regression line fitted to the RFcsa measurements per patient in the first 10 days of ICU admission. Correlations between baseline metabolite concentrations and baseline muscle mass, as well as between baseline metabolite concentrations and muscle loss were assessed using Pearson's test for correlations. To correct for multiple testing, the Benjamini-Hochberg procedure was used.

RESULTS

Seventeen patients were eligible for analysis. Mean age was 62 (SD ± 9) years and the cohort was predominantly male (76%). Four metabolites correlated with baseline muscle mass: creatinine (R = 0.5, p = 0.041), glycerophospholipid PC_ae_C30_0 (R = 0.5, p = 0.034) and two acylcarnitines: C14_2 (R = 0.5, p = 0.042) and C10_2 (R = 0.5, p = 0.049). For muscle loss, significant associations were found for histidine (R = -0.8, p = 0.002) and three glycerophospholipids; PC_aa_C40_2 (R = 0.7, p = 0.015), PC_ae_C40_1 (R = 0.6, p = 0.032) and PC_aa_C42_1 (R = 0.6, p = 0.037). After correction for multiple testing, no significant associations remained.

CONCLUSIONS

This exploratory analysis found certain metabolites to be associated with muscle mass and muscle loss. Future research, specifically addressing these metabolites is necessary to confirm or refute an association with muscle loss and determine their role as potential muscle loss marker.

Understanding Post-Sepsis Syndrome: How Can Clinicians Help?

Sepsis is a global health challenge, with over 49 million cases annually. Recent medical advancements have increased in-hospital survival rates to approximately 80%, but the escalating incidence of sepsis, owing to an ageing population, rise in chronic diseases, and antibiotic resistance, have also increased the number of sepsis survivors. Subsequently, there is a growing prevalence of "post-sepsis syndrome" (PSS). This syndrome includes long-term physical, medical, cognitive, and psychological issues after recovering from sepsis. PSS puts survivors at risk for hospital readmission and is associated with a reduction in health- and life span, both at short and long term, after hospital discharge. Comprehensive understanding of PSS symptoms and causative factors is vital for developing optimal care for sepsis survivors, a task of prime importance for clinicians. This review aims to elucidate our current knowledge of PSS and its relevance in enhancing post-sepsis care provided by clinicians.

The Loss of Temporal Muscle Volume is Associated with Poor Outcome in Patients with Subarachnoid Hemorrhage: An Observational Cohort Study

BACKGROUND

Intensive care unit (ICU) acquired weakness is a major contributor to poor functional outcome of ICU patients. Quantification of temporal muscle volume assessed on routine computed tomography (CT) scans may serve as a biomarker for muscle wasting in patients suffering from acute brain injury.

METHODS

This is a retrospective analysis of prospectively collected data. Temporal muscle volume was assessed on head CT scans of consecutive patients with spontaneous subarachnoid hemorrhage within prespecified time frames (on admission, then weekly ± 2 days). Whenever possible, temporal muscle volume was assessed bilaterally and averaged for the analysis. Poor functional outcome was defined as a 3-month modified Rankin Scale Score ≥ 3. Statistical analysis was performed using generalized estimating equations to handle repeated measurements within individuals.

RESULTS

The analysis comprised 110 patients with a median Hunt & Hess score of 4 (interquartile range 3-5). Median age was 61 (50-70) years, 73 patients (66%) were women. Baseline temporal muscle volume was 18.5 ± 0.78 cm3 and significantly decreased over time (p < 0.001) by a mean of 7.9% per week. Higher disease severity (p = 0.002), hydrocephalus (p = 0.020), pneumonia (p = 0.032), and bloodstream infection (p = 0.015) were associated with more pronounced muscle volume loss. Patients with poor functional outcome had smaller muscle volumes 2 and 3 weeks after subarachnoid hemorrhage compared with those with good outcome (p = 0.025). The maximum muscle volume loss during ICU stay was greater in patients with poor functional outcome (- 32.2% ± 2.5% vs. - 22.7% ± 2.5%, p = 0.008). The hazard ratio for poor functional outcome was 1.027 (95% confidence interval 1.003-1.051) per percent of maximum muscle volume loss.

CONCLUSIONS

Temporal muscle volume, which is easily assessable on routine head CT scans, progressively decreases during the ICU stay after spontaneous subarachnoid hemorrhage. Because of its association with disease severity and functional outcome, it may serve as a biomarker for muscle wasting and outcome prognostication.

Personalized nutrition therapy in critical care: 10 expert recommendations

Personalization of ICU nutrition is essential to future of critical care. Recommendations from American/European guidelines and practice suggestions incorporating recent literature are presented. Low-dose enteral nutrition (EN) or parenteral nutrition (PN) can be started within 48 h of admission. While EN is preferred route of delivery, new data highlight PN can be given safely without increased risk; thus, when early EN is not feasible, provision of isocaloric PN is effective and results in similar outcomes. Indirect calorimetry (IC) measurement of energy expenditure (EE) is recommended by both European/American guidelines after stabilization post-ICU admission. Below-measured EE (~ 70%) targets should be used during early phase and increased to match EE later in stay. Low-dose protein delivery can be used early (~ D1-2) (< 0.8 g/kg/d) and progressed to ≥ 1.2 g/kg/d as patients stabilize, with consideration of avoiding higher protein in unstable patients and in acute kidney injury not on CRRT. Intermittent-feeding schedules hold promise for further research. Clinicians must be aware of delivered energy/protein and what percentage of targets delivered nutrition represents. Computerized nutrition monitoring systems/platforms have become widely available. In patients at risk of micronutrient/vitamin losses (i.e., CRRT), evaluation of micronutrient levels should be considered post-ICU days 5-7 with repletion of deficiencies where indicated. In future, we hope use of muscle monitors such as ultrasound, CT scan, and/or BIA will be utilized to assess nutrition risk and monitor response to nutrition. Use of specialized anabolic nutrients such as HMB, creatine, and leucine to improve strength/muscle mass is promising in other populations and deserves future study. In post-ICU setting, continued use of IC measurement and other muscle measures should be considered to guide nutrition. Research on using rehabilitation interventions such as cardiopulmonary exercise testing (CPET) to guide post-ICU exercise/rehabilitation prescription and using anabolic agents such as testosterone/oxandrolone to promote post-ICU recovery is needed.

The impact of high versus standard enteral protein provision on functional recovery following intensive care admission (PRECISE trial): study protocol for a randomized controlled, quadruple blinded, multicenter, parallel group trial in mechanically ventilated patients

BACKGROUND

Critically ill patients are subject to severe skeletal muscle wasting during intensive care unit (ICU) stay, resulting in impaired short- and long-term functional outcomes and health-related quality of life. Increased protein provision may improve functional outcomes in ICU patients by attenuating skeletal muscle breakdown. Supporting evidence is limited however and results in great variety in recommended protein targets.

METHODS

The PRECISe trial is an investigator-initiated, bi-national, multi-center, quadruple-blinded randomized controlled trial with a parallel group design. In 935 patients, we will compare provision of isocaloric enteral nutrition with either a standard or high protein content, providing 1.3 or 2.0 g of protein/kg/day, respectively, when fed on target. All unplanned ICU admissions with initiation of invasive mechanical ventilation within 24 h of admission and an expected stay on ventilator support of at least 3 days are eligible. The study is designed to assess the effect of the intervention on functional recovery at 1, 3, and 6 months following ICU admission, including health-related quality of life, measures of muscle strength, physical function, and mental health. The primary endpoint of the trial is health-related quality of life as measured by the Euro-QoL-5D-5-level questionnaire Health Utility Score. Overall between-group differences will be assessed over the three time points using linear mixed-effects models.

DISCUSSION

The PRECISe trial will evaluate the effect of protein on functional recovery including both patient-centered and muscle-related outcomes.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT04633421 . Registered on November 18, 2020. First patient in (FPI) on November 19, 2020. Expected last patient last visit (LPLV) in October 2023.

Enteral nutrition management in critically ill adult patients and its relationship with intensive care unit-acquired muscle weakness: A national cohort study

OBJECTIVE

To assess the incidence and determinants of ICU-acquired muscle weakness (ICUAW) in adult patients with enteral nutrition (EN) during the first 7 days in the ICU and mechanical ventilation for at least 48 hours.

METHODS

A prospective, nationwide, multicentre cohort study in a national ICU network of 80 ICUs. ICU patients receiving invasive mechanical ventilation for at least 48 hours and EN the first 7 days of their ICU stay were included. The primary outcome was incidence of ICUAW. The secondary outcome was analysed, during days 3-7 of ICU stay, the relationship between demographic and clinical data to contribute to the onset of ICUAW, identify whether energy and protein intake can contribute independently to the onset of ICUAW and degree of compliance guidelines for EN.

RESULTS

319 patients were studied from 69 ICUs in our country. The incidence of ICUAW was 153/222 (68.9%; 95% CI [62.5%-74.7%]). Patients without ICUAW showed higher levels of active mobility (p = 0.018). The logistic regression analysis showed no effect on energy or protein intake on the onset of ICUAW. Overfeeding was observed on a significant proportion of patient-days, while more overfeeding (as per US guidelines) was found among patients with obesity than those without (42.9% vs 12.5%; p<0.001). Protein intake was deficient (as per US/European guidelines) during ICU days 3-7.

CONCLUSIONS

The incidence of ICUAW was high in this patient cohort. Early mobility was associated with a lower incidence of ICUAW. Significant overfeeding and deficient protein intake were observed. However, energy and protein intake alone were insufficient to explain ICUAW onset.

RELEVANCE TO CLINICAL PRACTICE

Low mobility, high incidence of ICUAW and low protein intake suggest the need to train, update and involve ICU professionals in nutritional care and the need for early mobilization of ICU patients.

Clofazimine-Mediated, Age-Related Changes in Skeletal Muscle Mitochondrial Metabolites

Mitochondrial health declines with age, and older patients can demonstrate dysfunction in mitochondrial-rich tissues, such as cardiac and skeletal muscle. Aged mitochondria may make older adults more susceptible to adverse drug reactions (ADRs). We assessed mitochondrial metabolic function by measuring two metabolites, l-carnitine and acetylcarnitine, to determine their effectiveness as candidate clinical biomarkers for age-related, drug-induced alterations in mitochondrial metabolism. To study age- and medication-related changes in mitochondrial metabolism, we administered the FDA-approved mitochondriotropic drug, clofazimine (CFZ), or vehicle for 8 weeks to young (4-week-old) and old (61-week-old) male C57BL/6J mice. At the end of treatment, whole blood and cardiac and skeletal muscle were analyzed for l-carnitine, acetylcarnitine, and CFZ levels; muscle function was measured via a treadmill test. No differences were found in blood or cardiac carnitine levels of CFZ-treated mice, but CFZ-treated mice displayed lost body mass and alterations in endurance and levels of skeletal muscle mitochondrial metabolites. These findings demonstrate the age-related susceptibility of the skeletal muscle to mitochondria drug toxicity. Since drug-induced alterations in mitochondrial metabolism in skeletal muscle were not reflected in the blood by l-carnitine or acetylcarnitine levels, drug-induced catabolism and changes in muscle function appear more relevant to stratifying individuals at increased risk for ADRs.

Prognostic values of modified NUTRIC score to assess outcomes in critically ill patients admitted to the intensive care units: prospective observational study

PURPOSE

Modified Nutrition Risk in the Critically Ill (NUTRIC) score (mNUTRIC score) have been validated as screening tool for quantifying risk of adverse outcome critically ill patients admitted to the intensive care units (ICUs). The aim of this study was to evaluate the prognostic value of mNUTRIC score to assess outcomes in this population.

MATERIALS AND METHODS

This prospective, observational study was conducted on adult patients admitted to the general ICUs of two university affiliated hospital in northwest of Iran. The association between the mNUTRIC score and outcomes was assessed using the univariate and multivariate binary logistic regression. The performance of mNUTRIC score to predict outcomes was assessed using the receiver operating characteristic (ROC)-curve.

RESULTS

In total 445 ICU patients were enrolled. Based on mNUTRIC score, 62 (13.9%) and 383 (86.1%) individuals were identified at high and low nutritional risk, respectively. The area under the curve (AUC) for predicting ICU mortality, using vasopressor, duration of vasopressor, and mechanical ventilation (MV) duration were (AUC: 0.973, 95% CI: 0.954-0.986, P < 0.001), (AUC: 0.807, 95% CI: 0.767-0.843, P < 0.001), (AUC: 0.726, 95% CI: 0.680-0.769, P < 0.001) and (AUC: 0.710, 95% CI: 0.666-0.752, P < 0.001), respectively.

CONCLUSIONS

An excellent and good predictive performance of the mNUTRIC score was found regarding ICU mortality and using vasopressor, respectively. However, this predictive was fair for MV and vasopressor duration and poor for ICU and hospital length of stay.

Course of recovery of respiratory muscle strength and its associations with exercise capacity and handgrip strength: A prospective cohort study among survivors of critical illness

BACKGROUND

Mechanical ventilation affects the respiratory muscles, but little is known about long-term recovery of respiratory muscle weakness (RMW) and potential associations with physical functioning in survivors of critical illness. The aim of this study was to investigate the course of recovery of RMW and its association with functional outcomes in patients who received mechanical ventilation.

METHODS

We conducted a prospective cohort study with 6-month follow-up among survivors of critical illness who received ≥ 48 hours of invasive mechanical ventilation. Primary outcomes, measured at 3 timepoints, were maximal inspiratory and expiratory pressures (MIP/MEP). Secondary outcomes were functional exercise capacity (FEC) and handgrip strength (HGS). Longitudinal changes in outcomes and potential associations between MIP/MEP, predictor variables, and secondary outcomes were investigated through linear mixed model analysis.

RESULTS

A total of 59 participants (male: 64%, median age [IQR]: 62 [53-66]) were included in this study with a median (IQR) ICU and hospital length of stay of 11 (8-21) and 35 (21-52) days respectively. While all measures were well below predicted values at hospital discharge (MIP: 68.4%, MEP 76.0%, HGS 73.3% of predicted and FEC 54.8 steps/2m), significant 6-month recovery was seen for all outcomes. Multivariate analyses showed longitudinal associations between older age and decreased MIP and FEC, and longer hospital length of stay and decreased MIP and HGS outcomes. In crude models, significant, longitudinal associations were found between MIP/MEP and FEC and HGS outcomes. While these associations remained in most adjusted models, an interaction effect was observed for sex.

CONCLUSION

RMW was observed directly after hospital discharge while 6-month recovery to predicted values was noted for all outcomes. Longitudinal associations were found between MIP and MEP and more commonly used measures for physical functioning, highlighting the need for continued assessment of respiratory muscle strength in deconditioned patients who are discharged from ICU. The potential of targeted training extending beyond ICU and hospital discharge should be further explored.

Perioperative Essential Amino Acid Supplementation Facilitates Quadriceps Muscle Strength and Volume Recovery After TKA: A Double-Blinded Randomized Controlled Trial

BACKGROUND

Perioperative essential amino acid (EAA) supplementation suppresses lower-limb muscle atrophy and promotes functional improvement in the first 4 weeks after total knee arthroplasty (TKA). However, its effect on the recovery of muscle volume and strength in the intermediate term is unclear. The aim of this study was to evaluate the effect of perioperative EAA supplementation on the recovery of lower-limb muscle volume and strength in the 2 years after TKA.

METHODS

Sixty patients who underwent unilateral TKA for primary knee osteoarthritis were included in this double-blinded randomized controlled trial. After excluding dropouts, 26 patients assigned to the EAA group (9 g/day) and 26 assigned to the placebo group (powdered lactose, 9 g/day) were available for analysis. Patients received EAA supplementation or a placebo from 1 week prior to surgery to 2 weeks after it. The rectus femoris muscle area was measured using ultrasonography and quadriceps muscle strength was measured isometrically with a handheld dynamometer, preoperatively and periodically up to 2 years postoperatively. Knee pain, knee range of motion, functional mobility, and Knee Society Score 2011 subjective scores were measured at each time point. Perioperative management, except for supplementation, was identical in the 2 groups.

RESULTS

Taking the baseline as 100%, the mean values in the EAA and placebo groups were 134% ± 31% and 114% ± 27%, respectively, for the rectus femoris muscle area and 159% ± 54% and 125% ± 40% for the quadriceps muscle strength, respectively, at 2 years after surgery. The differences were significant (p < 0.05). Clinical outcomes were not significantly different between the 2 groups.

CONCLUSIONS

Perioperative EAA supplementation contributes to the recovery of rectus femoris muscle volume and quadriceps muscle strength in the 2 years after TKA. The EAA supplementation did not impact clinical outcomes.

LEVEL OF EVIDENCE

Therapeutic Level I. See Instructions for Authors for a complete description of levels of evidence.

Determinants of in-hospital muscle loss in acute ischemic stroke - Results of the Muscle Assessment in Stroke Study (MASS)

BACKGROUND & AIMS

There is a change in the mass and composition of paretic and non-paretic skeletal muscles in the chronic phase of stroke. The multi-center, prospective, and observational Muscle Assessment in Stroke Study (MASS) was performed to evaluate the degree of muscle loss during the in-hospital acute stroke setting and determine factors contributing to this loss.

METHODS

Acute dysphagic ischemic stroke patients (n = 107) admitted to neuro-intensive care units were evaluated by computed tomography on days 1 and 14 after admission to determine the cross-sectional muscle area (CSMA) at the level of the mid-humerus, mid-thigh, and third lumbar vertebra. The percentage change in CSMA and variables associated with this change were evaluated by univariate and multivariate analyses.

RESULTS

There were significant reductions in CSMA in all the muscle groups analyzed; the most prominent change was observed in the arms (both: 14.2 ± 10.7%; paretic: 17.7 ± 11.6%; non-paretic: 10.1 ± 12.5%), followed by the muscles in the legs (both: 12.4 ± 8.7%; paretic: 12.9 ± 9.9%; non-paretic: 12.0 ± 9.3%) and L3-vertebra level (5.6 ± 9.8%) (P < 0.001 for all). Higher calorie (r = -0.378, P < 0.001) or protein (r = -0.352, P < 0.001) intake was negatively associated with the decrease in CSMA of upper extremities. A substantial protein (≥0.4 g/kg/d) or calorie (≥5 kcal/kg/d) gap between targeted or actual intake was related to a larger decrease in CSMA in all the anatomic regions (P ≤ 0.05 for all). Other significant predictors of muscle loss included history of diabetes mellitus, male sex, higher BMI, in-hospital infections, and the necessity for invasive mechanical ventilation.

CONCLUSIONS

There is a considerable degree of loss in the global muscle mass in acute ischemic stroke patients over a two-week period. Along with several factors, falling significantly behind the daily protein or calorie targets was related to the decrease in the muscle area. TRIAL REGISTRATION INFORMATION: clinicaltrials.gov identifier NCT03825419.

(Mal)nutrition in critical illness and beyond: a narrative review

Close liaison with ICU-trained dietitians and early initiation of nutrition is a fundamental principle of care of critically ill patients- this should be done while monitoring closely for refeeding syndrome. Enteral nutrition delivered by volumetric pumps should be used where possible, though parenteral nutrition should be started early in patients with high nutritional risk factors. Malnutrition and loss of muscle mass are common in patients who are admitted to ICUs and are prognostic for patient-centred outcomes including complications and mortality. Obesity is part of that story, and isocaloric and high-protein provision of nutrition is important in this group of patients who comprise a growing proportion of people treated. Assessing protein stores and appropriate dosing is, however, challenging in all groups of patients. It would be beneficial to develop strategies to reduce muscle wasting as well; various strategies including amino acid supplementation, ketogenic nutrition and exercise have been trialled, but the quality of data has been inadequate to address this phenomenon. Nutritional targets are rarely achieved in practice, and all ICUs should incorporate clear guidelines to help address this. These should include local nutritional and fasting guidelines and for the management of feed intolerance, early access to post-pyloric feeding and a multidisciplinary framework to support the importance of nutritional education.

Risk Factors of Decreased Abdominal Expiratory Muscle Thickness in Mechanically Ventilated Critically Ill Patients-The mNUTRIC Score is an Independent Predictor

Background

The expiratory abdominal skeletal muscles are an important component of the respiratory muscle pump, and their reduced thickness has been associated with difficult weaning. There is no objective score that may help clinicians to predict expiratory abdominal muscle thinning.

Patients and methods

This was a single-center retrospective study on 81 patients undergoing weaning from mechanical ventilation. The thickness of the four abdominal expiratory muscles-rectus abdominis (RA), internal oblique (IO), external oblique (EO), and transversus abdominis (TA) on the day of the first spontaneous breathing trial (SBT), was obtained. The various parameters of the patients with thinner RA, IO, EO, and TA below the determined thickness cut-off values, predicting difficult weaning was analyzed.

Results

Modified nutritional risk in critically ill (mNUTRIC) score was found to be an independent predictor of thinner IO muscle after logistic regression analysis [p = 0.001, adjusted OR 2.33, 95% CI (1.394-3.892)]. The mNUTRIC score was also an independent predictor of thinner EO (p = 0.014, adjusted OR 1.57) and RA muscle (p = 0.002, adjusted OR 1.69). The mNUTRIC cutoff score ≥4 predicted thinner IO (AUC 0.813, p < 0.001 sensitivity 71%, specificity 77%) and thinner EO (AUC 0.738, p < 0.001, 71% sensitivity, 67% specificity). The mNUTRIC score ≥3 predicted that at least one out of the four abdominal expiratory muscles will be thin (AUC 0.849, p < 0.001, 95% CI [0.763-0.935], sensitivity 87.5%, specificity 59%).

Conclusion

The mNUTRIC score is an independent predictor of thinner abdominal expiratory muscles in mechanically ventilated critically ill patients.

How to cite this article

Vishwas P, Amara V, Maddani SS, Chaudhuri S, Podder S. Risk Factors of Decreased Abdominal Expiratory Muscle Thickness in Mechanically Ventilated Critically Ill Patients-The mNUTRIC Score is an Independent Predictor. Indian J Crit Care Med 2023;27(1):8-15.

Low phase angle in critically ill older patients is associated with late mortality: A prospective study

OBJECTIVES

The aim of this study was to ascertain the accuracy of phase angle (PhA) as a predictor of mortality during intensive care unit (ICU) stay (M_ICU) and at 28 (M₂₈) and 60 d (M₆₀) after ICU admission among patients aged >60 y.

METHODS

Patients aged >60 y who were under mechanical ventilation (MV) ≥48 h were included once they were hemodynamically stable. PhA was measured by single-frequency bioelectrical impedance analysis up to 48 h after admission. ICU prognostic scores, functional scale, and nutritional assessments were performed in the first 24 h. Patients were followed for 60 d after ICU admission.

RESULTS

We enrolled 102 patients into the present study. PhA was significantly higher (P < 0.001) in survivors at M_ICU, M₂₈, and M₆₀. Areas under the receiving operator characteristic curves for M_ICU, M_28, and M₆₀ were 0.77 (95% confidence interval [CI], 0.67-0.86), 0.71 (95% CI, 0.60-0.82), and 0.71 (95% CI, 0.60-0.81), respectively. The PhA cutoff to predict mortality was 3.29° for males at M_ICU, M₂₈, and M₆₀ and lower for females at M₂₈ (2.63°) and M₆₀ (3.01°). PhA better discriminated M₆₀ than conventional prognostic scores. Logistic regression showed that even after controlling for other factors, PhA was a protective factor against late mortality. Survival analysis at 60 d revealed that low PhA was associated with lower median survival (18 versus 58 d; log-rank P < 0.001).

CONCLUSIONS

Low PhA values are associated with higher late mortality and a short survival time at 60 d in critically ill older adults. Low PhA values can be considered a useful ICU prognostic score in similar populations.

Phase angle and standardized phase angle from bioelectrical impedance measurements as a prognostic factor for mortality at 90 days in patients with COVID-19: A longitudinal cohort study

BACKGROUND & AIMS

Severe acute COVID-19 has taken on pandemic proportions with growing interest in identification of prognostic factors for mortality. Standardized bioelectrical impedance (BI) phase angle (SPhA), which is PhA adjusted by age and sex, has been related to mortality in patients with several diseases but never investigated in COVID-19. Inflammation, a consequence of COVID-19 infection, affects fluid status (hydration) and can be identified with PhA. The aim of this study was to determine the predictive role of PhA on 90 days survival of adults with COVID-19.

METHODS

We studied 127 consecutive patients diagnosed with COVID-19. BI measurements determined with a 50 kHz phase-sensitive BI device, body composition parameters and laboratory markers were evaluated as predictors of mortality.

RESULTS

Non-surviving COVID-19 patients had significantly lower PhA and SPhA values (p < 0.001) and increased hydration (p < 0.001) compared to surviving patients. Patients in the lowest SPhA quartile had increased (p < 0.001) mortality and hospital stay, hyperhydration (p < 0.001), increased inflammation biomarkers [CRP (p < 0.001)], decreased nutritional parameters: body mass cell index [BCMI (p < 0.001) albumin (p < 0.001)], and reduced other biomarkers [D-dimer (p = 0.002)]. Multivariate analysis (Cox regression) revealed that PhA and hydration status, adjusted for age, sex, BMI, diabetes, hypertension, dyslipidaemia or heart disease, were associated (p < 0.001) with increased mortality. The hazard ratio was 2.48 (95% CI, 1.60-3.84, p < 0.001) for PhA and 1.12 (95% CI, 1.04-1.20, p = 0.003) for hydration percentage. PhA <3.95° was the cut-off for predicting mortality in acute COVID-19 with 93.8% sensitivity and 66.7% specificity. PhA offers greater sensitivity as a predictive prognostic test at admission, compared to the established analytical parameters of poor prognosis (CRP, lymphocytes, prealbumin).

CONCLUSIONS

Low PhA (<3.95°), independent of age, sex, BMI, and comorbidities, is a significant predictor of mortality risk in COVID-19. These findings suggest that the evaluation of body composition with single-frequency phase-sensitive BI measurements should be included in the routine clinical assessment of COVID-19 patients at hospital admission to identify patients at increased mortality risk.

The time course of disuse muscle atrophy of the lower limb in health and disease

Short, intermittent episodes of disuse muscle atrophy (DMA) may have negative impact on age related muscle loss. There is evidence of variability in rate of DMA between muscles and over the duration of immobilization. As yet, this is poorly characterized. This review aims to establish and compare the time-course of DMA in immobilized human lower limb muscles in both healthy and critically ill individuals, exploring evidence for an acute phase of DMA and differential rates of atrophy between and muscle groups. MEDLINE, Embase, CINHAL and CENTRAL databases were searched from inception to April 2021 for any study of human lower limb immobilization reporting muscle volume, cross-sectional area (CSA), architecture or lean leg mass over multiple post-immobilization timepoints. Risk of bias was assessed using ROBINS-I. Where possible meta-analysis was performed using a DerSimonian and Laird random effects model with effect sizes reported as mean differences (MD) with 95% confidence intervals (95% CI) at various time-points and a narrative review when meta-analysis was not possible. Twenty-nine studies were included, 12 in healthy volunteers (total n = 140), 18 in patients on an Intensive Therapy Unit (ITU) (total n = 516) and 3 in patients with ankle fracture (total n = 39). The majority of included studies are at moderate risk of bias. Rate of quadriceps atrophy over the first 14 days was significantly greater in the ITU patients (MD -1.01 95% CI -1.32, -0.69), than healthy cohorts (MD -0.12 95% CI -0.49, 0.24) (P < 0.001). Rates of atrophy appeared to vary between muscle groups (greatest in triceps surae (-11.2% day 28), followed by quadriceps (-9.2% day 28), then hamstrings (-6.5% day 28), then foot dorsiflexors (-3.2% day 28)). Rates of atrophy appear to decrease over time in healthy quadriceps (-6.5% day 14 vs. -9.1% day 28) and triceps surae (-7.8% day 14 vs. -11.2% day 28), and ITU quadriceps (-13.2% day 7 vs. -28.2% day 14). There appears to be variability in the rate of DMA between muscle groups, and more rapid atrophy during the earliest period of immobilization, indicating different mechanisms being dominant at different timepoints. Rates of atrophy are greater amongst critically unwell patients. Overall evidence is limited, and existing data has wide variability in the measures reported. Further work is required to fully characterize the time course of DMA in both health and disease.

Muscle size, strength, and physical function in response to augmented calorie delivery: A TARGET sub-study

PURPOSE

Augmented calories may attenuate muscle loss experienced in critical illness. This exploratory sub-study assessed the effect of augmented calorie delivery on muscle mass, strength, and function.

MATERIALS AND METHODS

Patients in The Augmented versus Routine approach to Giving Energy Trial (TARGET) randomised to 1.5 kcal/ml or 1.0 kcal/ml enteral formulae at a single-centre were included. Ultrasound-derived muscle layer thickness (MLT) at quadriceps, forearm and mid-upper arm, and handgrip strength, were measured weekly from baseline to hospital discharge, and 3- and 6-months. Physical function was assessed at 3- and 6-months using the 'get up and go' and 6-min walk tests. Data are mean ± SD.

RESULTS

Eighty patients were recruited (1.5 kcal: n = 38, 58 ± 14y, 60%M, APACHE II 20 ± 7; 1.0 kcal: n = 42, 54 ± 18y, 66%M, APACHE II 22 ± 10). The 1.5 kcal/ml group received more calories with no difference in quadriceps MLT at any timepoint including ICU discharge (primary outcome) (2.90 ± 1.27 vs 2.39 ± 1.06 cm; P = 0.141). Relationships were similar for all MLT measures, handgrip strength, and 6-min walk test. Patients in the 1.5 kcal/ml group had improved 'get up and go' test at 3-months (6.66 ± 1.33 vs. 9.11 ± 2.94 s; P = 0.014).

CONCLUSION

Augmented calorie delivery may not attenuate muscle loss or recovery of strength or function 6-months post-ICU, but this requires exploration in a larger trial.

Prognostic significance of postoperative loss of skeletal muscle mass in patients underwent coronary artery bypass grafting

Background

Increasing life expectancy of coronary artery bypass grafting (CABG) remains to be the major concern of cardiac surgeons. However, few studies have investigated the effect of postoperative skeletal muscle index (SMI) loss on prognosis. This study aims to evaluate the prognostic role of postoperative SMI loss ≥ 5% after CABG, in order to develop a novel nomogram to predict overall survival (OS).

Methods

Patients underwent CABG via midline sternotomy from December 2015 to March 2021 were recruited in this study. Preoperative and postoperative 3 months chest computed tomography (CT) images were compared to assess changes in SMI at T12 level. Based on this, patients were classified into the presence or absence of SMI loss ≥ 5%. The association between postoperative SMI loss ≥ 5% and OS was then analyzed by the Kaplan-Meier curves and Cox model. A novel nomogram incorporating independent clinical prognostic variables was also developed.

Results

The study enrolled 506 patients receiving CABG, of whom 98 patients experienced T12 SMI loss ≥ 5% and had a significantly worse OS (P < 0.0001). Multivariate regression analysis showed that T12 SMI per cent change (%T12 SMI-change) was an independent prognostic factor for OS (HR = 0.809, 95% CI = 0.749–0.874). The nomogram incorporating %T12 SMI-change with other variables was accurate for predicting OS. Besides, we also found that postoperative oral nutritional supplement (ONS) can rescue T12 SMI loss.

Conclusion

Postoperative SMI loss can predict survival outcome after CABG. The nomogram incorporating changes in SMI provides a superior performance than existing systems.

Multi-omic comparative analysis of COVID-19 and bacterial sepsis-induced ARDS

BACKGROUND

Acute respiratory distress syndrome (ARDS), a life-threatening condition characterized by hypoxemia and poor lung compliance, is associated with high mortality. ARDS induced by COVID-19 has similar clinical presentations and pathological manifestations as non-COVID-19 ARDS. However, COVID-19 ARDS is associated with a more protracted inflammatory respiratory failure compared to traditional ARDS. Therefore, a comprehensive molecular comparison of ARDS of different etiologies groups may pave the way for more specific clinical interventions.

METHODS AND FINDINGS

In this study, we compared COVID-19 ARDS (n = 43) and bacterial sepsis-induced (non-COVID-19) ARDS (n = 24) using multi-omic plasma profiles covering 663 metabolites, 1,051 lipids, and 266 proteins. To address both between- and within- ARDS group variabilities we followed two approaches. First, we identified 706 molecules differently abundant between the two ARDS etiologies, revealing more than 40 biological processes differently regulated between the two groups. From these processes, we assembled a cascade of therapeutically relevant pathways downstream of sphingosine metabolism. The analysis suggests a possible overactivation of arginine metabolism involved in long-term sequelae of ARDS and highlights the potential of JAK inhibitors to improve outcomes in bacterial sepsis-induced ARDS. The second part of our study involved the comparison of the two ARDS groups with respect to clinical manifestations. Using a data-driven multi-omic network, we identified signatures of acute kidney injury (AKI) and thrombocytosis within each ARDS group. The AKI-associated network implicated mitochondrial dysregulation which might lead to post-ARDS renal-sequalae. The thrombocytosis-associated network hinted at a synergy between prothrombotic processes, namely IL-17, MAPK, TNF signaling pathways, and cell adhesion molecules. Thus, we speculate that combination therapy targeting two or more of these processes may ameliorate thrombocytosis-mediated hypercoagulation.

CONCLUSION

We present a first comprehensive molecular characterization of differences between two ARDS etiologies-COVID-19 and bacterial sepsis. Further investigation into the identified pathways will lead to a better understanding of the pathophysiological processes, potentially enabling novel therapeutic interventions.

Gene Ontology (GO)-Driven Inference of Candidate Proteomic Markers Associated with Muscle Atrophy Conditions

Skeletal muscle homeostasis is essential for the maintenance of a healthy and active lifestyle. Imbalance in muscle homeostasis has significant consequences such as atrophy, loss of muscle mass, and progressive loss of functions. Aging-related muscle wasting, sarcopenia, and atrophy as a consequence of disease, such as cachexia, reduce the quality of life, increase morbidity and result in an overall poor prognosis. Investigating the muscle proteome related to muscle atrophy diseases has a great potential for diagnostic medicine to identify (i) potential protein biomarkers, and (ii) biological processes and functions common or unique to muscle wasting, cachexia, sarcopenia, and aging alone. We conducted a meta-analysis using gene ontology (GO) analysis of 24 human proteomic studies using tissue samples (skeletal muscle and adipose biopsies) and/or biofluids (serum, plasma, urine). Whilst there were few similarities in protein directionality across studies, biological processes common to conditions were identified. Here we demonstrate that the GO analysis of published human proteomics data can identify processes not revealed by single studies. We recommend the integration of proteomics data from tissue samples and biofluids to yield a comprehensive overview of the human skeletal muscle proteome. This will facilitate the identification of biomarkers and potential pathways of muscle-wasting conditions for use in clinics.

Intensive care unit-acquired weakness: From molecular mechanisms to its impact in COVID-2019

Intensive Care Unit-Acquired Weakness (ICU-AW) is a generalized and symmetric neuromuscular dysfunction associated with critical illness and its treatments. Its incidence is approximately 80% in intensive care unit patients, and it manifests as critical illness polyneuropathy, critical illness myopathy, and muscle atrophy. Intensive care unit patients can lose an elevated percentage of their muscle mass in the first days after admission, producing short- and long-term sequelae that affect patients’ quality of life, physical health, and mental health. In 2019, the world was faced with coronavirus disease 2019 (COVID-19), caused by the acute respiratory syndrome coronavirus 2. COVID-19 produces severe respiratory disorders, such as acute respiratory distress syndrome, which increases the risk of developing ICU-AW. COVID-19 patients treated in intensive care units have shown early diffuse and symmetrical muscle weakness, polyneuropathy, and myalgia, coinciding with the clinical presentation of ICU-AW. Besides, these patients require prolonged intensive care unit stays, invasive mechanical ventilation, and intensive care unit pharmacological therapy, which are risk factors for ICU-AW. Thus, the purposes of this review are to discuss the features of ICU-AW and its effects on skeletal muscle. Further, we will describe the mechanisms involved in the probable development of ICU-AW in severe COVID-19 patients.

Multi-omic comparative analysis of COVID-19 and bacterial sepsis-induced ARDS

Background

Acute respiratory distress syndrome (ARDS), a life-threatening condition characterized by hypoxemia and poor lung compliance, is associated with high mortality. ARDS induced by COVID-19 has similar clinical presentations and pathological manifestations as non-COVID-19 ARDS. However, COVID-19 ARDS is associated with a more protracted inflammatory respiratory failure compared to traditional ARDS. Therefore, a comprehensive molecular comparison of ARDS of different etiologies groups may pave the way for more specific clinical interventions.

Methods and Findings

In this study, we compared COVID-19 ARDS (n=43) and bacterial sepsis-induced (non-COVID-19) ARDS (n=24) using multi-omic plasma profiles covering 663 metabolites, 1,051 lipids, and 266 proteins. To address both between- and within-ARDS group variabilities we followed two approaches. First, we identified 706 molecules differently abundant between the two ARDS etiologies, revealing more than 40 biological processes differently regulated between the two groups. From these processes, we assembled a cascade of therapeutically relevant pathways downstream of sphingosine metabolism. The analysis suggests a possible overactivation of arginine metabolism involved in long-term sequelae of ARDS and highlights the potential of JAK inhibitors to improve outcomes in bacterial sepsis-induced ARDS. The second part of our study involved the comparison of the two ARDS groups with respect to clinical manifestations. Using a data-driven multi-omic network, we identified signatures of acute kidney injury (AKI) and thrombocytosis within each ARDS group. The AKI-associated network implicated mitochondrial dysregulation which might lead to post-ARDS renal-sequalae. The thrombocytosis-associated network hinted at a synergy between prothrombotic processes, namely IL-17, MAPK, TNF signaling pathways, and cell adhesion molecules. Thus, we speculate that combination therapy targeting two or more of these processes may ameliorate thrombocytosis-mediated hypercoagulation.

Conclusion

We present a first comprehensive molecular characterization of differences between two ARDS etiologies - COVID-19 and bacterial sepsis. Further investigation into the identified pathways will lead to a better understanding of the pathophysiological processes, potentially enabling novel therapeutic interventions.

The Role of Circadian Clock Genes in Critical Illness: The Potential Role of Translational Clock Gene Therapies for Targeting Inflammation, Mitochondrial Function, and Muscle Mass in Intensive Care

The Earth's 24-h planetary rotation, with predictable light and heat cycles, has driven profound evolutionary adaptation, with prominent impacts on physiological mechanisms important for surviving critical illness. Pathways of interest include inflammation, mitochondrial function, energy metabolism, hypoxic signaling, apoptosis, and defenses against reactive oxygen species. Regulation of these by the cellular circadian clock (BMAL-1 and its network) has an important influence on pulmonary inflammation; ventilator-associated lung injury; septic shock; brain injury, including vasospasm; and overall mortality in both animals and humans. Whether it is cytokines, the inflammasome, or mitochondrial biogenesis, circadian medicine represents exciting opportunities for translational therapy in intensive care, which is currently lacking. Circadian medicine also represents a link to metabolic determinants of outcome, such as diabetes and cardiovascular disease. More than ever, we are appreciating the problem of circadian desynchrony in intensive care. This review explores the rationale and evidence for the importance of the circadian clock in surviving critical illness.

Post-remission outcomes in AML patients with high hyperleukocytosis and inaugural life-threatening complications

Introduction

Patients with hyperleukocytic (HL) acute myeloid leukemia (AML) are at higher risk of early death. Initial management of these patients is challenging, not fully codified and heterogenous. Retrospective studies showed that several symptomatic measures might decrease early death rate but long-term data are scarce. We aimed to analyze whether the therapeutic measures carried out urgently at diagnosis may influence the outcome among HL AML patients having achieved who survived inaugural complications.

Methods

We retrospectively reviewed all medical charts from patients admitted to Saint-Louis Hospital between January, 1^st 1997 and December, 31st 2018 with newly diagnosed AML and white blood cell (WBC) count above 50x10⁹/L. Outcome measures were cumulative incidence of relapse (CIR), treatment-related mortality (TRM) defined as relapse-free death, and overall survival. Univariate and multivariate analyses were performed using Cox proportional hazards models.

Results

A total of 184 patients with HL AML in complete remission (CR) were included in this study. At 2 years after CR. 62.5% of patients were alive, at 5 years, cumulated incidence of relapse was 55.8%. We found that every therapeutic measure, including life-sustaining therapies carried out in the initial phase of the disease, did not increase the relapse risk. The use of hydroxyurea for more than 4 days was associated with a higher risk of relapse. At the end of the study, 94 patients (51.1%) were still alive including 23 patients out of 44 aged less than 60 yo that were able to return to work.

Conclusion

We show that the use of emergency measures including life sustaining therapies does not come at the expense of a higher risk of relapse or mortality, except in the case of prolonged use of hydroxyurea. Patients with HL AML should be able to benefit from all available techniques, regardless of their initial severity.

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.

Comparison of the effects of different calorie amounts of enteral nutrition in hypercatabolism associated with ghrelin-POMC in endotoxemic rats

Background

Hypercatabolism often occurs in critically ill patients, and it increases infection rates and mortality in these patients. Enteral nutrition (EN) is commonly used in case of hypercatabolism. However, the effect of amount of calories in EN on hypercatabolism remains unexplored.

Objective

Here, we compared the effect of low-calorie, medium-calorie and high-calorie EN on hypercatabolism in the acute phase of endotoxemia, which is associated with gastrointestinal hormones and hypothalamic neuropeptide proopiomelanocortin (POMC).

Methods

Overall 84 adult male Sprague–Dawley rats were used for research. A set of rats were divided into 5 groups, Control (NS) and lipopolysaccharide (LPS) groups were fed a standard chow diet; LPS + L (LPS + 40 kcal/kg/day EN), LPS + M (LPS + 80 kcal/kg/day EN) and LPS + H (LPS + 120 kcal/kg/day EN) groups received EN through a gastric tube for 3 days. Another set of rats were used for parallel control experiment and divided into 5 groups: NS + F (saline + fasting) and LPS + F (LPS + fasting) groups were given no food, NS + L (saline + 40 kcal/kg/day EN), NS + M (saline + 80 kcal/kg/day EN) and NS + H (saline + 120 kcal/kg/day EN) groups received EN through a gastric tube for 3 days. Hypercatabolism was evaluated by assessing skeletal muscle protein synthesis and atrophy, insulin resistance, and corticosterone levels. Moreover, serum inflammatory factors, gastrointestinal hormones, hypothalamic ghrelin, growth hormone secretagogue receptor-1α, hypothalamic neuropeptide, and intestinal injury indicators were detected.

Results

Low-calorie EN effectively increased serum and hypothalamic ghrelin possibly due to slight intestinal barrier damage, thereby decreasing hypothalamic POMC expression; consequently, it alleviated rat insulin resistance, reduced blood cortisol levels and muscle atrophy, and improved the survival rate of rats in the acute phase of endotoxemia. Interestingly, with an increase in calories in enteral nutrition, the aforementioned effects did not increase.

Conclusions

Low-calorie EN could effectively increase gastrointestinal hormone ghrelin by reducing intestinal damage and suppressing POMC expression to ameliorate hypercatabolism when compared with medium-calorie and high-calorie EN. Therefore Low-calorie EN may be preferred for providing EN in the acute stage of endotoxemia.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12986-022-00663-7.

Nutrition priorities in obese critically ill patients

PURPOSE OF REVIEW

During critical illness, several neuroendocrine, inflammatory, immune, adipokine, and gastrointestinal tract hormone pathways are activated; some of which are more intensified among obese compared with nonobese patients. Nutrition support may mitigate some of these effects. Nutrition priorities in obese critically ill patients include screening for nutritional risk, estimation of energy and protein requirement, and provision of macronutrients and micronutrients.

RECENT FINDINGS

Estimation of energy requirement in obese critically ill patients is challenging because of variations in body composition among obese patients and absence of reliable predictive equations for energy expenditure. Whereas hypocaloric nutrition with high protein has been advocated in obese critically ill patients, supporting data are scarce. Recent studies did not show differences in outcomes between hypocaloric and eucaloric nutrition, except for better glycemic control. Sarcopenia is common among obese patients, and the provision of increased protein intake has been suggested to mitigate catabolic changes especially after the acute phase of critical illness. However, high-quality data on high protein intake in these patients are lacking. Micronutrient deficiencies among obese critically ill patients are common but the role of their routine supplementation requires further study.

SUMMARY

An individualized approach for nutritional support may be needed for obese critically ill patients but high-quality evidence is lacking. Future studies should focus on nutrition priorities in this population, with efficient and adequately powered studies.

Nutritional state assessed by ultrasonography, but not by bioelectric impedance, predicts 28-day mortality in critically ill patients. Prospective cohort study

BACKGROUND & AIMS

Malnutrition is a disease associated with unfavorable outcomes and high prevalence among critically ill patients. The primary aim of the study was to correlate the nutritional status of patients recently admitted to the intensive care unit (ICU) with the 28-day mortality rate. The secondary aim was to establish cut-off values for the bioelectrical impedance analysis (BIA) and ultrasonography (USG) methods for the classification of the nutritional status of critically ill patients.

METHODS

Cohort-type prospective observational study design, with the inclusion of critically ill clinical-surgical patients, ≥18 years old, mechanically ventilated. Their nutritional status was assessed by phase angle and skeletal muscle mass (using BIA), and the sectional area of the rectus femoris muscle (RFM) (using USG) within the first 48 h of ICU admission.

RESULTS

Among the patients included (n = 160), the non-survivors had lower values related to the survivors for averages of the phase angle (4.4 ± 1.5° vs 4.9 ± 1.2°; p = 0.041) and sectional area of the RFM (6.1 ± 1.6 cm²/m²vs 7.4 ± 1.8 cm²/m²; p = 0.030). Cut-off values were identified using the ROC curves for phase angle (≤4.4°), skeletal muscle mass (≤19.2 kg/m²), and sectional area of the RFM (≤5.9 cm²/m²). In multivariate logistic regression analysis, the sectional area of the RFM (≤5.9 cm²/m²) was the only independent predictor of 28-day mortality (OR = 6.08; p = 0.028). In the survival analysis, greater survival at 28 days was demonstrated for patients with phase angle >4.4° (p = 0.020) and sectional area of the RFM >5.9 cm²/m² (p = 0.001). Malnourished patients had higher mortality than nourished patients according to the phase angle (31.5% vs 15.1%, respectively; p = 0.015) and the sectional area of the RFM (38.9% vs 6.3%, respectively; p = 0.001).

CONCLUSIONS

The USG of the RFM is an efficient method for both classifying the nutritional status at ICU admission and assessing the prognosis of critically ill patients.

Functional Outcomes and Their Association With Physical Performance in Mechanically Ventilated Coronavirus Disease 2019 Survivors at 3 Months Following Hospital Discharge: A Cohort Study

OBJECTIVES

We performed a comprehensive health assessment in mechanically ventilated coronavirus disease 2019 survivors to assess the impact of respiratory and skeletal muscle injury sustained during ICU stay on physical performance at 3 months following hospital discharge.

DESIGN

Preregistered prospective observational cohort study.

SETTING

University hospital ICU.

PATIENTS

All mechanically ventilated coronavirus disease 2019 patients admitted to our ICU during the first European pandemic wave.

MEASUREMENTS AND MAIN RESULTS

At 3 months after hospital discharge, 46 survivors underwent a comprehensive physical assessment (6-min walking distance, Medical Research Council sum score and handgrip strength), a full pulmonary function test, and a chest CT scan which was used to analyze skeletal muscle architecture. In addition, patient-reported outcomes measures were collected. Physical performance assessed by 6-minute walking distance was below 80% of predicted in 48% of patients. Patients with impaired physical performance had more muscle weakness (Medical Research Council sum score 53 [51-56] vs 59 [56-60]; p < 0.001), lower lung diffusing capacity (54% [44-66%] vs 68% of predicted [61-72% of predicted]; p = 0.002), and higher intermuscular adipose tissue area (p = 0.037). Reduced lung diffusing capacity and increased intermuscular adipose tissue were independently associated with physical performance.

CONCLUSIONS

Physical disability is common at 3 months in severe coronavirus disease 2019 survivors. Lung diffusing capacity and intermuscular adipose tissue assessed on CT were independently associated with walking distance, suggesting a key role for pulmonary function and muscle quality in functional disability.

Protective effect of isosteviol sodium against LPS-induced multiple organ injury by regulating of glycerophospholipid metabolism and reducing macrophage-driven inflammation

Sepsis is a severe inflammatory disorder that can lead to multiple organ injury. Isosteviol sodium (STV-Na) is a terpenoid derived from stevioside that exerts anti-inflammatory, antioxidant and antiapoptotic activities. However, the influence of STV-Na on sepsis remains unknown. Here, we assessed the potential effects of STV-Na on sepsis and multiple organ injury induced by lipopolysaccharide (LPS). We found that STV-Na increased the survival rate of mice treat with LPS, significantly improved the functions of the heart, lung, liver, and kidney, reduced the production of inflammatory cytokines and decreased macrophage infiltration. Moreover, Multiorgan metabolomics analysis demonstrated that glutathione metabolism, purine metabolism, glycerophospholipid metabolism and pantothenate and CoA biosynthesis, were significantly altered by STV-Na. This study provides novel insights into the metabolite changes of multiple organ injury in septic mice, which may help characterize the underlying mechanism and provide an improved understanding of the therapeutic effects of STV-Na on sepsis.

Qualitative and quantitative muscle ultrasound changes in patients with COVID-19-related ARDS

OBJECTIVES

Severe forms of the novel coronavirus-19 (COVID-19) are associated with systemic inflammation and hypercatabolism. The aims of this study were to compare the time course of the size and quality of both rectus femoris and diaphragm muscles between critically ill, COVID-19 survivors and non-survivors and to explore the correlation between the change in muscles size and quality with the amount of nutritional support delivered and the cumulative fluid balance.

METHODS

This was a prospective observational study in the general intensive care unit (ICU) of a tertiary care hospital for COVID-19. The right rectus femoris cross-sectional area and the right diaphragm thickness, as well as their echo densities were assessed within 24 h from ICU admission and on day 7. We recorded anthropometric and biochemical data, respiratory mechanics and gas exchange, daily fluid balance, and the number of calories and proteins administered.

RESULTS

Twenty-eight patients were analyzed (65 ± 10 y of age; 80% men, body mass index 30 ± 7.8 kg/m²). Rectus femoris and diaphragm sizes were significantly reduced at day 7 (median = -26.1 [interquartile ratio [IQR], = -37.8 to -15.2] and -29.2% [-37.8% to -19.6%], respectively) and this reduction was significantly higher in non-survivors. Both rectus femoris and diaphragm echo density were significantly increased at day 7, with a significantly higher increase in non-survivors. The change in both rectus femoris and diaphragm size at day 7 was related to the cumulative protein deficit (R = 0.664, P < 0.001 and R = 0.640, P < 0.001, respectively), whereas the change in rectus femoris and diaphragm echo density was related to the cumulative fluid balance (R = 0.734, P < 0.001 and R = 0.646, P < 0.001, respectively).

CONCLUSIONS

Early changes in muscle size and quality seem related to the outcome of critically ill COVID-19 patients, and to be influenced by nutritional and fluid management strategies.

Relationship Between Nutrition Intake and Outcome After Subarachnoid Hemorrhage: Results From the International Nutritional Survey

BACKGROUND

A previous study suggested an association between low caloric intake(CI), negative nitrogen balance, and poor outcome after subarachnoid hemorrhage(SAH). Objective of this multinational, multicenter study was to investigate whether clinical outcomes vary by protein intake(PI) or CI in SAH patients adjusting for the nutritional risk as judged by the modified NUTrition Risk in the Critically Ill (mNUTRIC) score.

METHODS

The International Nutrition Survey(INS) 2007-2014 was utilized to describe the characteristics, outcomes and nutrition use. A subgroup of patients from 2013 and 2014(when NUTRIC score was captured) examined the association between CI and PI and time to discharge alive(TTDA) from hospital using Cox regression models, adjusting for nutrition risk classified by the mNUTRIC score as low(0-4) or high(5-9).

RESULTS

There were 489 SAH patients(57% female with a mean ± SD age 57.5 ± 13.9 years, BMI of 25.9 ± 5.3 kg/m² and APACHE-2 score 19.4 ± 7.0. Majority(85%) received enteral nutrition(EN) only, with a time to initiation of EN of 35.4 ± 35.2 hours. 64% had EN interrupted. Patients received a CI of 14.6 ± 7.1 calories/kg/day and PI 0.7 ± 0.3 grams/kg/day corresponding to 59% and 55% of total prescribed CI and PI respectively. In the 2013 and 2014 subgroup there were 226 SAH patients with a mNUTRIC score of 3.4 ± 1.8. Increased CI and PI were associated with faster TTDA among high mNUTRIC patients(HR per 20% of prescription received = 1.34[95% CI,1.03 -1.76] for CI and 1.44[1.07 -1.93] for PI), but not low mNUTRIC patients(CI: HR = 0.95[0.77 -1.16] PI:0.95[0.78 -1.16]).

CONCLUSIONS

Results from this multicenter study found that SAH patients received under 60% of their prescribed CI and PI. Further, achieving greater CI and PI in hi risk SAH patients was associated with improved TTDA. mNUTRIC serves to identify SAH patients that benefit most from artificial nutrition and efforts to optimize protein and caloric delivery in this subpopulation should be maximized.

Anabolic effects of oral leucine-rich protein with and without β-hydroxybutyrate on muscle protein metabolism in a novel clinical model of systemic inflammation-a randomized crossover trial

BACKGROUND

β-lactoglobulin (BLG) stimulates muscle protein synthesis and β-hydroxybutyrate (BHB) inhibits muscle breakdown. Whether combining the 2 can additively attenuate disease-induced muscle loss is unknown.

OBJECTIVE

Based on previous observations of anticatabolic effects of protein and ketone bodies during inflammation, and using a novel model combining ongoing systemic inflammation, fasting, and immobilization, we tested whether the anticatabolic muscle response to oral amino acids is altered compared with control conditions, as well as whether coadministration of oral BHB and BLG further improves the muscle anabolic response. Muscle net balance (NBphe) was the primary outcome and intramyocellular signals were assessed.

METHODS

In a randomized crossover design, 8 young men underwent either preconditioning with LPS (prestudy day: 1 ng/kg, study day: 0.5 ng/kg) combined with a 36-h fast and bed rest to mimic catabolic inflammatory disease (CAT) or an overnight fast (control [CTR]) prior to isocaloric nutritional interventions on 3 occasions separated by ∼6 wk (range 42 to 83 d).

RESULTS

NBphe increased similarly upon all conditions (interaction P = 0.65). From comparable baseline rates, both Rdphe [muscle synthesis, median ratio (95% CI): 0.44 (0.23, 0.86) P = 0.017] and Raphe [muscle breakdown, median ratio (95% CI): 0.46 (0.27, 0.78) P = 0.005] decreased following BHB + BLG compared with BLG. BLG increased Rdphe more under CAT conditions compared with CTR (interaction P = 0.02). CAT increased inflammation, energy expenditure, and lipid oxidation and decreased Rdphe and anabolic signaling [mammalian target of rapamycin (mTOR) and eukaryotic translation initiation factor 4E-binding protein 1 (4EPB1) phosphorylation].

CONCLUSION

In contrast to our initial hypothesis, NBphe increased similarly following BLG during CAT and CTR conditions; CAT however, specifically stimulated the BLG-mediated increase in protein synthesis, whereas BHB coadministration did not affect NBphe, but distinctly dampened the BLG-induced increase in muscle amino acid fluxes thereby liberating circulating amino acids for anabolic actions elsewhere.

The effect of higher versus lower protein delivery in critically ill patients: a systematic review and meta-analysis of randomized controlled trials

Background

The optimal protein dose in critical illness is unknown. We aim to conduct a systematic review of randomized controlled trials (RCTs) to compare the effect of higher versus lower protein delivery (with similar energy delivery between groups) on clinical and patient-centered outcomes in critically ill patients.

Methods

We searched MEDLINE, EMBASE, CENTRAL and CINAHL from database inception through April 1, 2021.We included RCTs of (1) adult (age ≥ 18) critically ill patients that (2) compared higher vs lower protein with (3) similar energy intake between groups, and (4) reported clinical and/or patient-centered outcomes. We excluded studies on immunonutrition. Two authors screened and conducted quality assessment independently and in duplicate. Random-effect meta-analyses were conducted to estimate the pooled risk ratio (dichotomized outcomes) or mean difference (continuous outcomes).

Results

Nineteen RCTs were included (n = 1731). Sixteen studies used primarily the enteral route to deliver protein. Intervention was started within 72 h of ICU admission in sixteen studies. The intervention lasted between 3 and 28 days. In 11 studies that reported weight-based nutrition delivery, the pooled mean protein and energy received in higher and lower protein groups were 1.31 ± 0.48 vs 0.90 ± 0.30 g/kg and 19.9 ± 6.9 versus 20.1 ± 7.1 kcal/kg, respectively. Higher vs lower protein did not significantly affect overall mortality [risk ratio 0.91, 95% confidence interval (CI) 0.75–1.10, p = 0.34] or other clinical or patient-centered outcomes. In 5 small studies, higher protein significantly attenuated muscle loss (MD −3.44% per week, 95% CI −4.99 to −1.90; p < 0.0001).

Conclusion

In critically ill patients, a higher daily protein delivery was not associated with any improvement in clinical or patient-centered outcomes. Larger, and more definitive RCTs are needed to confirm the effect of muscle loss attenuation associated with higher protein delivery.

PROSPERO registration number: CRD42021237530

Supplementary Information

The online version contains supplementary material available at 10.1186/s13054-021-03693-4.

Impact of β-hydroxy-β-methylbutyrate (HMB) on muscle loss and protein metabolism in critically ill patients: A RCT

PURPOSE

Muscle wasting deteriorates life quality after critical illness and increases mortality. Wasting starts upon admission to intensive care unit (ICU). We aimed to determine whether β-hydroxy-β-methylbutyrate (HMB), a metabolite of leucine, can attenuate this process.

METHODS

Prospective randomized, placebo-controlled double blind trial.

INCLUSION CRITERIA

ICU patients depending on mechanical ventilation on day 3 having a functional gastrointestinal tract. They were randomized to HMB (3 g/day) or placebo (maltodextrin) from day 4 on for 30 days.

PRIMARY OUTCOME

magnitude of loss of skeletal muscle area (SMA) of the quadriceps femoris measured by ultrasound at days 4 and 15.

SECONDARY OUTCOMES

body composition, change in protein metabolism assessed by amino acids tracer pulse, and global health at 60 days. Data are mean [95% CI]. Statistics by ANCOVA with correction for confounders sex, age and/or BMI.

RESULTS

Thirty patients completed the trial, aged 65 [59, 71] years, SAPS2 score 48 [43, 52] and SOFA 8.5 [7.4, 9.7]. The loss of total SMA was 11% between days 4 and 15 (p < 0.001), but not different between the groups (p = 0.86). In the HMB group, net protein breakdown (Δ Estimate HMB-Placebo: -153 [-242, -63]; p = 0.0021) and production of several amino acid was significantly reduced, while phase angle increased more (0.66 [0.09, 1.24]; p = 0.0247), and SF-12 global health improved more (Δ Estimate HMB-Placebo: 27.39 [1.594, 53.19], p = 0.04).

CONCLUSION

HMB treatment did not significantly reduce muscle wasting over 10 days of observation (primary endpoint), but resulted in significantly improved amino acid metabolism, reduced net protein breakdown, a higher phase angle and better global health. CLINICALTRIALS.

GOV IDENTIFIER

NCT03628365.