Global muscle strength but not grip strength predicts mortality and length of stay in a general population in a surgical intensive care unit

Photobiomodulation therapy (red/NIR LEDs) reduced the length of stay in intensive care unit and improved muscle function: A randomized, triple-blind, and sham-controlled trial

CONTEXT

Photobiomodulation therapy (PBMT) has been widely used to improve strength, fatigue resistance and increase muscle mass in healthy individuals. These effects could help critically ill patients admitted to intensive care units (ICUs) who show reduced mobility and muscle strength. ICU-acquired weakness lessens overall health and increases the patient's length of stay in the ICU.

OBJECTIVE

This study evaluated the effects of PBMT using low intensity light-emitting diodes (LEDs) on the mobility and muscle strength (functional capacity) and length of stay of patients admitted to hospital ICU.

METHODS

This randomized, triple-blind, sham-controlled trial was conducted in a hospital ICU. Sixty patients were randomly assigned to two equal groups: (a) PBMT and (b) Sham. PBMT was applied daily to patients until their discharge from the ICU, using a flexible neoprene array of 264 LEDs (120 at 635 nm, 1.2 mW each; 144 at 880 nm, 15 mW each) for 90s (207.36 Joules) at each site. Ten sites were located bilaterally on the thighs, legs, arms, and forearms ventrally and dorsally, 15 min totaling 2,073.6 Joules per session. Outcomes were length of stay (in h) until discharge from the ICU, muscle strength by the Medical Research Council (MRC) score and handgrip dynamometry (HGD), patient mobility by Intensive Care Unit Mobility Scale (IMS) and the Simplified Acute Physiology Score 3 (SAPS 3) for predicting mortality of patients admitted to the ICU.

RESULTS

PBMT reduced the average length of stay in the ICU by ~30% (p = 0.028); increased mobility (IMS: 255% vs. 110% p = 0.007), increased muscle strength (MRC: 12% vs. -9% p = 0.001) and HGD (34% vs. -13% p < 0.001), and the SAPS3 score was similar (p > 0.05).

CONCLUSION

The results suggest that daily PBMT can reduce the length of stay of ICU patients and increase muscle strength and mobility.

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

PURPOSE

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

METHODS

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

RESULTS

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

CONCLUSION

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

A systematic review and meta-analysis of the clinimetric properties of the core outcome measurement instruments for clinical effectiveness trials of nutritional and metabolic interventions in critical illness (CONCISE)

BACKGROUND

CONCISE is an internationally agreed minimum set of outcomes for use in nutritional and metabolic clinical research in critically ill adults. Clinicians and researchers need to be aware of the clinimetric properties of these instruments and understand any limitations to ensure valid and reliable research. This systematic review and meta-analysis were undertaken to evaluate the clinimetric properties of the measurement instruments identified in CONCISE.

METHODS

Four electronic databases were searched from inception to December 2022 (MEDLINE via Ovid, EMBASE via Ovid, CINAHL via Healthcare Databases Advanced Search, CENTRAL via Cochrane). Studies were included if they examined at least one clinimetric property of a CONCISE measurement instrument or recognised variation in adults ≥ 18 years with critical illness or recovering from critical illness in any language. The COnsensus-based Standards for the selection of health Measurement INstruments (COSMIN) checklist for systematic reviews of Patient-Reported Outcome Measures was used. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses were used in line with COSMIN guidance. The COSMIN checklist was used to evaluate the risk of bias and the quality of clinimetric properties. Overall certainty of the evidence was rated using a modified Grading of Recommendations, Assessment, Development and Evaluation approach. Narrative synthesis was performed and where possible, meta-analysis was conducted.

RESULTS

A total of 4316 studies were screened. Forty-seven were included in the review, reporting data for 12308 participants. The Short Form-36 Questionnaire (Physical Component Score and Physical Functioning), sit-to-stand test, 6-m walk test and Barthel Index had the strongest clinimetric properties and certainty of evidence. The Short Physical Performance Battery, Katz Index and handgrip strength had less favourable results. There was limited data for Lawson Instrumental Activities of Daily Living and the Global Leadership Initiative on Malnutrition criteria. The risk of bias ranged from inadequate to very good. The certainty of the evidence ranged from very low to high.

CONCLUSIONS

Variable evidence exists to support the clinimetric properties of the CONCISE measurement instruments. We suggest using this review alongside CONCISE to guide outcome selection for future trials of nutrition and metabolic interventions in critical illness.

TRIAL REGISTRATION

PROSPERO (CRD42023438187). Registered 21/06/2023.

Quadriceps handheld dynamometry during the post-ICU trajectory: using strictly the same body position is mandatory for repeated measures

BACKGROUND

The level of quadriceps strength (QS) generated in the supine or seated position is not similar. For QS follow-up from intensive care unit (ICU) stay to recovery, getting comparable measures is essential. This study aimed to develop and validate new equations for estimating QS in a given position based on the measurement taken in another one.

METHODS AND RESULTS

Isometric QS was measured using a handheld dynamometer and a standardized protocol in a supine and in a seated position. In a first cohort of 77 healthy adults, two QS conversion equations were developed using a multivariate model integrating independent parameters such as age, sex, body mass index (BMI) and baseline QS. These equations were tested in two cohorts for external validation, using the interclass correlation coefficient (ICC) and Bland-Altman graphical method. Only one was validated in the second cohort (62 different healthy adults): the ICC was 0.87 (95% CI 0.59-0.94) and the bias was - 0.49 N/Kg (limits of agreement: - 1.76-0.78 N/kg). However, this equation did not perform well in the third cohort (50 ICU survivors): the ICC was 0.60 (95% CI 0.24-0.78), and the bias was - 0.53 N/Kg (limits of agreement: - 1.01-2.07 N/kg).

CONCLUSIONS

As no conversion equation has been validated in the present study, repeated QS measurements should be performed strictly in the same standardized and documented position.

Multiomic characterisation of the long-term sequelae of SARS survivors: a clinical observational study

BACKGROUND

We aimed to characterise the long-term health outcomes of survivors of severe acute respiratory syndrome (SARS) and determine their recovery status and possible immunological basis.

METHODS

We performed a clinical observational study on 14 health workers who survived SARS coronavirus infection between Apr 20, 2003 and Jun 6, 2003 in Haihe Hospital (Tianjin, China). Eighteen years after discharge, SARS survivors were interviewed using questionnaires on symptoms and quality of life, and received physical examination, laboratory tests, pulmonary function tests, arterial blood gas analysis, and chest imaging. Plasma samples were collected for metabolomic, proteomic, and single-cell transcriptomic analyses. The health outcomes were compared 18 and 12 years after discharge. Control individuals were also health workers from the same hospital but did not infect with SARS coronavirus.

FINDINGS

Fatigue was the most common symptom in SARS survivors 18 years after discharge, with osteoporosis and necrosis of the femoral head being the main sequelae. The respiratory function and hip function scores of the SARS survivors were significantly lower than those of the controls. Physical and social functioning at 18 years was improved compared to that after 12 years but still worse than the controls. Emotional and mental health were fully recovered. Lung lesions on CT scans remained consistent at 18 years, especially in the right upper lobe and left lower lobe lesions. Plasma multiomics analysis indicated an abnormal metabolism of amino acids and lipids, promoted host defense immune responses to bacteria and external stimuli, B-cell activation, and enhanced cytotoxicity of CD8⁺ T cells but impaired antigen presentation capacity of CD4⁺ T cells.

INTERPRETATION

Although health outcomes continued to improve, our study suggested that SARS survivors still suffered from physical fatigue, osteoporosis, and necrosis of the femoral head 18 years after discharge, possibly related to plasma metabolic disorders and immunological alterations.

FUNDING

This study was funded by the Tianjin Haihe Hospital Science and Technology Fund (HHYY-202012) and Tianjin Key Medical Discipline (Specialty) Construction Project (TJYXZDXK-063B, TJYXZDXK-067C).

Association of Multiple Cardiovascular Risk Factors with Musculoskeletal Function in Acute Coronary Syndrome Ward Inpatients

This study explored the association of multiple risk factors with musculoskeletal function in adults hospitalized for acute coronary syndrome. Sixty-nine inpatients (55 ± 6 years; 67% male) admitted to the cardiology ward within <12 h were assessed regarding stress, smoking, alcoholism, hypertension, diabetes mellitus, and obesity. The musculoskeletal function was assessed by predicted values of handgrip strength of the dominant hand (HGS-D%) and maximal inspiratory and expiratory pressures (MIP% and MEP%, respectively). After adjustment by age and sex, drinking habits showed the strongest linear association with the total number of cardiovascular disease risk factors [standardized ß, p-value] (ß = 0.110, p < 0.001), followed by smoking load (ß = 0.028, p = 0.009). Associations were also observed for HGS-D% with mean blood pressure (ß = 0.019 [0.001; 0.037], p = 0.048); MIP% with mean blood pressure (ß = 0.025 [0.006; 0.043], p = 0.013); and MEP% with drinking habits (ß = 0.009 [0.002; 0.016], p = 0.013) and body mass index (ß = 0.008 [0.000; 0.015], p = 0.035). Peripheral and respiratory muscle strength must be interpreted in the context of its association with cardiovascular disease risk factors in adults hospitalized for acute coronary syndrome.

Predictors of Basic Activity in Daily Living and Length of Hospitalization in Patients with COVID-19

Background: Patients recovered from COVID-19 often suffer from the sequelae of the disease, which can hinder the patients’ activity in daily living. Early recognition of the patients at risk of prolonged hospitalization and impaired physical functioning is crucial for early intervention. We aim to identify the predictors of prolonged hospitalization and impaired activity in daily living in this study. Methods: COVID-19 patients hospitalized in a medical center were divided into two groups according to the Barthel index three months after discharge and the median length of hospital stay, respectively. Chi-square test and Mann–Whitney U test were performed to check the differences between the two groups in patient characteristics as well as hematology tests at the emergency department, the intensive care unit mobility scale (ICUMS), and the medical research council sum score (MRCSS). Logistic regression and the receiver operating characteristic curve analysis were further performed for the factors with significant differences between the two groups. Results: Both ICUMS and MRCSS showed significant differences between the groups. The ICUMS had an odds ratio of 0.61 and the MRCSS of 0.93 in predicting a Barthel index score less than 100 three months after discharge. The MRCSS had an odds ratio of 0.82 in predicting a prolonged length of hospital stay. Conclusion: Both ICUMS and MRCSS upon admission are predictive of a Barthel index score of less than 100 three months after discharge. On the other hand, only MRCSS has predictive value of a prolonged hospitalization.

Association between frailty and clinical outcomes in surgical patients admitted to intensive care units: a systematic review and meta-analysis

BACKGROUND

Preoperative frailty may be a strong predictor of adverse postoperative outcomes. We investigated the association between frailty and clinical outcomes in surgical patients admitted to the ICU.

METHODS

PubMed, Embase, and Ovid MEDLINE were searched for relevant articles. We included full-text original English articles that used any frailty measure, reporting results of surgical adult patients (≥18 yr old) admitted to ICUs with mortality as the main outcome. Data on mortality, duration of mechanical ventilation, ICU and hospital length of stay, and discharge destination were extracted. The quality of included studies and risk of bias were assessed using the Newcastle Ottawa Scale. Data were synthesised according to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines.

RESULTS

Thirteen observational studies met inclusion criteria. In total, 58 757 patients were included; 22 793 (39.4%) were frail. Frailty was associated with an increased risk of short-term (risk ratio [RR]=2.66; 95% confidence interval [CI]: 1.99-3.56) and long-term mortality (RR=2.66; 95% CI: 1.32-5.37). Frail patients had longer ICU length of stay (mean difference [MD]=1.5 days; 95% CI: 0.8-2.2) and hospital length of stay (MD=3.9 days; 95% CI: 1.4-6.5). Duration of mechanical ventilation was longer in frail patients (MD=22 h; 95% CI: 1.7-42.3) and they were more likely to be discharged to a healthcare facility (RR=2.34; 95% CI: 1.36-4.01).

CONCLUSION

Patients with frailty requiring postoperative ICU admission for elective and non-elective surgeries had increased risk of mortality, lengthier admissions, and increased likelihood of non-home discharge. Preoperative frailty assessments and risk stratification are essential in patient and clinician planning, and critical care resource utilisation.

CLINICAL TRIAL REGISTRATION

PROSPERO CRD42020210121.

Handgrip strength to predict extubation outcome: a prospective multicenter trial

BACKGROUND

ICU-acquired weakness (ICUAW) has been shown to be associated with prolonged duration of mechanical ventilation and extubation failure. It is usually assessed through Medical Research Council (MRC) score, a time-consuming score performed by physiotherapists. Handgrip strength (HG) can be monitored very easily at the bedside. It has been shown to be a reproducible and reliable marker of global muscular strength in critical care patients. We sought to test if muscular weakness, as assessed by handgrip strength, was associated with extubation outcome.

METHODS

Prospective multicenter trial over an 18 months period in six mixed ICUs. Adults receiving mechanical ventilation for at least 48 h were eligible. Just before weaning trial, HG, Maximal Inspiratory Pressure (MIP), Peak Cough Expiratory Flow (PCEF) and Medical Research Council (MRC) score were registered. The attending physicians were unaware of the tests results and weaning procedures were conducted according to guidelines. Occurrence of unscheduled reintubation, non-invasive ventilation (NIV) or high-flow nasal continuous oxygen (HFNC) because of respiratory failure within 7 days after extubation defined extubation failure. The main outcome was the link between HG and extubation outcome.

RESULTS

233 patients were included. Extubation failure occurred in 51 (22.5%) patients, 39 (17.2%) required reintubation. Handgrip strength was 12 [6-20] kg and 12 [8-20] kg, respectively, in extubation success and failure (p = 0.85). There was no association between extubation outcome and MRC score, MIP or PCEF. Handgrip strength was well correlated with MRC score (r = 0.718, p < 0.0001). ICU and hospital length of stay were significantly higher in the subset of patients harboring muscular weakness as defined by handgrip performed at the first weaning trial (respectively, 15 [10-25] days vs. 11 [7-17] days, p = 0.001 and 34 [19-66] days vs. 22 [15-43] days, p = 0.002).

CONCLUSION

No association was found between handgrip strength and extubation outcome. Whether this was explained by the appropriateness of the tool in this specific setting, or by the precise impact of ICUAW on extubation outcome deserves to be further evaluated. Trial registration Clinical Trials; NCT02946502, 10/27/2016, URL: https://clinicaltrials.gov/ct2/results?cond=&term=gripwean&cntry=&state=&city=&dist=.

Impact of peripheral muscle strength on prognosis after extubation and functional outcomes in critically ill patients: a feasibility study

The influence of peripheral muscle strength on prognosis after extubation and subsequent functional outcomes is not evident. The objectives of this study were to determine (1) whether peripheral muscle strength can be used as a predictor for patients' prognoses after extubation, and (2) whether the peripheral muscle strength before extubation is correlated with patients' subsequent ambulation ability and in-hospital mortality. This study was a prospective observational cohort study. A hand-held dynamometer was used for evaluated the muscle strength of the biceps and quadriceps right before extubation. Besides, after the patients had been transferred from the ICU to the general ward, a 2-minute walk test was performed. A total of 52 patients were enrolled in this study, and the rate of extubation failure was 15%. The muscle strength of the quadriceps was significantly correlated with the prognosis after extubation, 48% of the patients were able to ambulate after being transferred to the general ward. The overall mortality rate was 11%, and there was a significant correlation between the biceps muscle strength and in-hospital mortality. Peripheral muscle strength may serve as an important predictor of a patients' prognoses after extubation. Poor peripheral muscle strength is indicative of not only a higher risk of re-intubation but also higher in-hospital mortality and poorer functional outcomes.Trial registration: ISRCTN16370134. Registered 30 May 2019, prospectively registered. https://www.isrctn.com/ISRCTN16370134 .

Physical recovery of COVID-19 pneumosepsis ICU survivors compared with non-COVID pneumosepsis ICU survivors during post-ICU hospitalization: The RECOVID retrospective cohort study

Background

Coronavirusdisease 2019 (COVID‐19) pneumosepsis survivors are at a high risk of developing intensive care unit (ICU)–acquired weakness (ICUAW) because of high incidence of acute respiratory distress syndrome and the common need for prolonged invasive ventilation. It remains unknown whether regular postpneumosepsis physical rehabilitation strategies are suitable for this extraordinary patient category.

Methods

We retrospectively compared the physical recovery of COVID‐19 and non‐COVID pneumosepsis ICU survivors during post‐ICU hospitalization, defined as the difference in performance on the Medical Research Council Sum‐Score (MRC‐SS), Chelsea Critical Care Physical Assessment tool (CPAx), and percentage of predicted handgrip strength (POP‐HGS). An analysis of covariance model was built using age, sex, Barthel index, body mass index, admission Acute Physiology And Chronic Health Evaluation II score, adequacy of protein delivery during ICU stay, and ward length of stay as covariates.

Results

Thirty‐five COVID‐19 ICU patients could be compared with 21 non‐COVID pneumosepsis ICU survivors. All patients scored ≤48 on the MRC‐SS at ICU discharge, indicating ICUAW. When controlling for covariates, COVID‐19 patients performed worse on all physical assessments upon ICU discharge, but had improved more at hospital discharge on the MRC‐SS (ɳ² = 0.214, P =.002) and CPAx (ɳ² = 0.153, P =.011). POP‐HGS remained lower in COVID‐19 patients throughout hospital stay.

Conclusion

COVID‐19 ICU survivors are vulnerable to ICUAW, but they show better tendency towards physical rehabilitation than non‐COVID pneumosepsis ICU survivors during the post‐ICU hospitalization period regarding MRC‐SS and CPAx. COVID‐19 ICU patients might benefit from early, more intensive physical therapy.

Bedside voluntary and evoked forces evaluation in intensive care unit patients: a narrative review

Around one third of intensive care unit (ICU) patients will develop severe neuromuscular alterations, known as intensive care unit-acquired weakness (ICUAW), during their stay. The diagnosis of ICUAW is difficult and often delayed as a result of sedation or delirium. Indeed, the clinical evaluation of both Medical Research Council score and maximal voluntary force (e.g., using handgrip and/or handheld dynamometers), two independent predictors of mortality, can be performed only in awake and cooperative patients. Transcutaneous electrical/magnetic stimulation applied over motor nerves combined with the development of dedicated ergometer have recently been introduced in ICU patients in order to propose an early and non-invasive measurement of evoked force. The aim of this narrative review is to summarize the different tools allowing bedside force evaluation in ICU patients and the related experimental protocols. We suggest that non-invasive electrical and/or magnetic evoked force measurements could be a relevant strategy to characterize muscle weakness in the early phase of ICU and diagnose ICUAW.

A follow-up study of respiratory and physical function after discharge in patients with redetectable positive SARS-CoV-2 nucleic acid results following recovery from COVID-19

Objective

The aim of this study was to evaluate the respiratory and physical function of patients who retested positive for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) RNA during post-coronavirus disease 2019 (COVID-19) rehabilitation.

Methods

A total of 302 discharged COVID-19 patients were included. Discharged patients were followed up for 14 days to 6 months. The modified Medical Research Council (mMRC) dyspnea scale, Borg rating of perceived exertion, and manual muscle testing (MMT) scores on day 14 and at 6 months after discharge were compared between the redetectable positive (RP) and non-RP (NRP) groups. Prognoses of respiratory and physical function were compared between patients who recovered from moderate and severe COVID-19.

Results

Of the study patients, 7.6% were RP. The proportion of patients who used antiviral drugs was significantly lower in the RP group than in the NRP group. There were no differences in mMRC, Borg, or MMT scores within the RP and NRP groups. The mMRC, Borg, and MMT scores were worse for patients with severe disease when compared to those with moderate disease at both follow-up time points.

Conclusions

COVID-19 patients who did not take antiviral drugs were more likely to be RP after discharge. The recovery of respiratory and physical function was not related to re-positivity during rehabilitation, but was related to disease severity during hospitalization.

Accuracy of the step test to evaluate lower limb muscle strength in community-dwelling older women

OBJECTIVE

to investigate the accuracy of the step test (ST) to evaluate total lower limb muscle strength (LLMS) in older women.

DESIGN

observational cross-sectional study.

METHODS

119 community-dwelling older women were submitted to the ST and LLMS evaluation (isometric peak torque of eight muscle groups of the dominant lower limb). The capacity of the ST to discriminate older women with reduced LLMS was measured using ROC curve, followed by the posttest probability (PoTP) calculation.

RESULTS

a ST score of 0.24 cm per cm of participant's height presents a sensitivity of 63.3%, specificity of 77%; enhances the PoTP from 48% to 72% for positive test and decreases the PoTP from 48% to 31% for negative test.

CONCLUSION

the ST may complement the clinical screening of reduced LLMS in older women, given that it is a simple and quick low-cost test and allows the evaluation of each lower limb separately.

ICU outcomes can be predicted by noninvasive muscle evaluation: a meta-analysis

BACKGROUND

The relationship between muscle function in critically ill patients assessed using bedside techniques and clinical outcomes has not been systematically described. We aimed to evaluate the association between muscle weakness assessed by bedside evaluation and mortality or weaning from mechanical ventilation, and the capacity of each evaluation tool to predict outcomes.

METHODS

Five databases (PubMed, Embase, CINAHL, Cochrane Library, Science Direct) were searched from January 2000 to December 2018. Data were extracted and random effects meta-analyses were performed.

RESULTS

60 studies were analysed, including 4382 patients. Intensive care unit (ICU)-related muscle weakness was associated with an increase in overall mortality with odds ratios ranging from 1.2 (95% CI 0.60-2.40) to 4.48 (95% CI 1.49-13.42). Transdiaphragmatic twitch pressure had the highest predictive capacity for overall mortality, with a sensitivity of 0.87 (95% CI 0.76-0.93) and a specificity of 0.36 (95% CI 0.27-0.43). The area under the curve (AUC) was 0.74 (95% CI 0.70-0.78). Muscle weakness was associated with an increase in mechanical ventilation weaning failure rate with an odds ratio ranging from 2.64 (95% CI 0.72-9.64) to 19.07 (95% CI 9.35-38.9). Diaphragm thickening fraction had the highest predictive capacity for weaning failure with a sensitivity of 0.76 (95% CI 0.67-0.83) and a specificity of 0.86 (95% CI 0.78-0.92). The AUC was 0.86 (95% CI 0.83-0.89).

CONCLUSION

ICU-related muscle weakness detected by bedside techniques is a serious issue associated with a high risk of death or prolonged mechanical ventilation. Evaluating diaphragm function should be a clinical priority in the ICU.

Skeletal Muscle Aging Atrophy: Assessment and Exercise-Based Treatment

In the ordinary course of aging, individuals change their body composition, mainly reducing their skeletal muscle mass and increasing their fat mass. In association, muscle strength and functionality also decrease. The geriatric assessment allows knowing the baseline situation of the patients, determines the impact of diseases, and defines specific treatments. There are various tools to evaluate the health condition of older people. These tools include the assessment scales of necessary Activities of Daily Living (ADL) and Instrumental Activities of Daily Living (IADL), physical and functional assessment scales, and instruments that assess the cognitive state of the person. There are several strategies that have been proposed to combat skeletal muscle atrophy due to aging, such as physical exercise, nutritional supplements, or drugs. Some researchers have highlighted the efficacy of the combination of the mentioned strategies. In this chapter, we will focus only on physical exercise as a strategy to reduce skeletal muscle loss during aging.

Effects of Opioids Given to Facilitate Mechanical Ventilation on Sleep Apnea After Extubation in the Intensive Care Unit

Study Objectives

Following extubation in the intensive care unit (ICU), upper airway (UA) edema and respiratory depressants may promote UA dysfunction. We tested the hypothesis that opioids increase the risk of sleep apnea early after extubation.

Methods

Fifty-six ICU patients underwent polysomnography the night after extubation. Airflow limitation during wakefulness was identified using bedside spirometry. Correlation and ordinal regression analyses were used to quantify the effects of preextubation opioid dose on postextubation apnea-hypopnea index (AHI) and severity of sleep apnea and whether or not inspiratory airway obstruction (ratio of maximum expiratory and inspiratory airflows at 50% of vital capacity [MEF50/MIF50] ≥ 1) during wakefulness predicts airway obstruction during sleep. Data were adjusted for age, gender, body mass index, as well as a generalized propensity score balanced for APACHE II, score for preoperative prediction of obstructive sleep apnea, duration of mechanical ventilation, chronic obstructive pulmonary disease, and a procedural severity score for morbidity.

Results

Sleep apnea (AHI ≥ 5) was present in 40 (71%) of the 56 patients. Morphine equivalent dose given 24 hours prior extubation predicted obstructive respiratory events during sleep (r = 0.35, p = .01) and sleep apnea (odds ratio [OR] 1.17; 95% confidence interval [CI] 1.02-1.34). Signs of inspiratory UA obstruction (MEF50/MIF50 ≥ 1) assessed by bedside spirometry were strongly associated with sleep apnea (OR 5.93; 95% CI 1.16-30.33).

Conclusions

High opioid dose given 24 hours prior to extubation increases the likelihood of postextubation sleep apnea in the ICU, particularly in patients with anatomical vulnerability following extubation.

Influence of the initial level of consciousness on early, goal-directed mobilization: a post hoc analysis

PURPOSE

Early mobilization within 72 h of intensive care unit (ICU) admission improves functional status at hospital discharge. We aimed to assess the effectiveness of early, goal-directed mobilization in critically ill patients across a broad spectrum of initial consciousness levels.

METHODS

Post hoc analysis of the international, randomized, controlled, outcome-assessor blinded SOMS trial conducted 2011-2015. Randomization was stratified according to the immediate post-injury Glasgow Coma Scale (GCS) (≤ 8 or > 8). Patients received either SOMS-guided mobility treatment with a facilitator or standard care. We used general linear models to test the hypothesis that immediate post-randomization GCS modulates the intervention effects on functional independence at hospital discharge.

RESULTS

Two hundred patients were included in the intention-to-treat analysis. The significant effect of early, goal-directed mobilization was consistent across levels of GCS without evidence of effect modification, for the primary outcome functional independence at hospital discharge (p = 0.53 for interaction), as well as average achieved mobility level during ICU stay (mean achieved SOMS level) and functional status at hospital discharge measured with the functional independence measure. In patients with low GCS, delay to first mobilization therapy was longer (0.7 ± 0.2 days vs. 0.2 ± 0.1 days, p = 0.008), but early, goal-directed mobilization compared with standard care significantly increased functional independence at hospital discharge in this subgroup of patients with immediate post-randomization GCS ≤ 8 (OR 3.67; 95% CI 1.02-13.14; p = 0.046).

CONCLUSION

This post hoc analysis of a randomized controlled trial suggests that early, goal-directed mobilization in patients with an impaired initial conscious state (GCS ≤ 8) is not harmful but effective.

Influenza A Virus Infection Induces Muscle Wasting via IL-6 Regulation of the E3 Ubiquitin Ligase Atrogin-1

Muscle dysfunction is common in patients with adult respiratory distress syndrome and is associated with morbidity that can persist for years after discharge. In a mouse model of severe influenza A pneumonia, we found the proinflammatory cytokine IL-6 was necessary for the development of muscle dysfunction. Treatment with a Food and Drug Administration-approved Ab antagonist to the IL-6R (tocilizumab) attenuated the severity of influenza A-induced muscle dysfunction. In cultured myotubes, IL-6 promoted muscle degradation via JAK/STAT, FOXO3a, and atrogin-1 upregulation. Consistent with these findings, atrogin-1+/- and atrogin-1-/- mice had attenuated muscle dysfunction following influenza infection. Our data suggest that inflammatory endocrine signals originating from the injured lung activate signaling pathways in the muscle that induce dysfunction. Inhibiting these pathways may limit morbidity in patients with influenza A pneumonia and adult respiratory distress syndrome.

Enhanced skeletal muscle regrowth and remodelling in massaged and contralateral non-massaged hindlimb

KEY POINTS

Muscle fibre cross sectional area is enhanced with massage in the form of cyclic compressive loading during regrowth after atrophy. Massage enhances protein synthesis of the myofibrillar and cytosolic, but not the mitochondrial fraction, in muscle during regrowth. Focal adhesion kinase activation and satellite cell number are elevated in muscles undergoing massage during regrowth. Muscle fibre cross sectional area and protein synthesis of the myofibrillar fraction, but not DNA synthesis, are elevated in muscle of the contralateral non-massaged limb. Massage in the form of cyclic compressive loading is a potential anabolic intervention during muscle regrowth after atrophy.

ABSTRACT

Massage, in the form of cyclic compressive loading (CCL), is associated with multiple health benefits, but its potential anabolic effect on atrophied muscle has not been investigated. We hypothesized that the mechanical activity associated with CCL induces an anabolic effect in skeletal muscle undergoing regrowth after a period of atrophy. Fischer-Brown Norway rats at 10 months of age were hindlimb unloaded for a period of 2 weeks. The rats were then allowed reambulation with CCL applied at a 4.5 N load at 0.5 Hz frequency for 30 min every other day for four bouts during a regrowth period of 8 days. Muscle fibre cross sectional area was enhanced by 18% with massage during regrowth compared to reloading alone, and this was accompanied by elevated myofibrillar and cytosolic protein as well as DNA synthesis. Focal adhesion kinase phosphorylation indicated that CCL increased mechanical stimulation, while a higher number of Pax7+ cells likely explains the elevated DNA synthesis. Surprisingly, the contralateral non-massaged limb exhibited a comparable 17% higher muscle fibre size compared to reloading alone, and myofibrillar protein synthesis, but not DNA synthesis, was also elevated. We conclude that massage in the form of CCL induces an anabolic response in muscles regrowing after an atrophy-inducing event. We suggest that massage can be used as an intervention to aid in the regrowth of muscle lost during immobilization.

Quantitative Evaluation of Muscle Function, Gait, and Postural Control in People Experiencing Critical Illness After Discharge From the Intensive Care Unit

BACKGROUND

The path to recovery of muscle strength and mobility following discharge from the intensive care unit (ICU) has not been well described.

OBJECTIVE

The study objective was to quantify muscle function, gait, and postural control at 3 and 6 months after discharge in people who were recovering from critical illness and who were ventilated for 7 days or more.

DESIGN

This was a nested longitudinal study with continuous inclusion of individuals over a 2-year period and with age- and sex-matched controls.

METHODS

Twenty-four people were tested at 3 months after ICU discharge; 16 of them (67%) were reevaluated at 6 months (post-ICU group). Healthy controls (n = 12) were tested at a single time point. Muscle function of the knee extensors (KEs), plantar flexors (PFs), and dorsiflexors (DFs) was assessed on a dynamometer. Gait was measured using an electronic walkway, and postural control was measured with 2 portable force plates.

RESULTS

Muscle weakness was observed across all muscle groups at 3 months, with the greatest strength reductions in the ankle PFs (45%) and DFs (30%). Muscle power was reduced in the PFs and DFs but was not reduced in the KEs. Gait in the post-ICU group was characterized by a narrower step, longer stride, and longer double-support time than in the controls. Improvements were found in KE strength and in stride time and double-support time during gait at 6 months. Leg muscle strength and power had moderate associations with gait velocity, step width, and stride length (r = .44–.65).

LIMITATIONS

The small heterogeneous sample of people with a high level of function was a limitation of this study.

CONCLUSIONS

Muscle strength and power were impaired at 6 months after ICU discharge and were associated with gait parameters. Future studies are needed to examine the role of muscle strength and power training in post-ICU rehabilitation programs to improve mobility.

Influence of muscle strength on early mobility in critically ill adult patients: Systematic literature review

BACKGROUND

Muscle strength may be one indicator of readiness to mobilize that can be used to guide decisions regarding early mobility efforts and to progressively advance mobilization.

OBJECTIVES

To provide a synthesis of current measures of muscle strength in the assessment of early mobilization in critically ill adult patients who are receiving MV therapy.

METHODS

Research studies conducted between 2000-2015 were identified using PubMed, CINHAL, MEDLINE, and the Cochrane Database of Systematic Reviews databases using the search terms "muscle strength", "intensive care", "mechanical ventilation" and "muscle weakness".

RESULTS

Nine articles used manual muscle testing, the Medical Research Council scale and/or hand-held dynamometer to provide objective measures for assessing muscle strength in the critically ill adult patient population.

CONCLUSIONS

Further research is needed to examine the application of standardized measures of muscle strength for guiding decisions regarding early and progressive advancement of mobility goals in adult ICU patients on MV.

Predictive factors of in-hospital mortality in ventilated intensive care unit: A prospective cohort study

Although it is clear that ventilated intensive care unit (ICU) patients have worse outcomes than those who are not, information about the risk factors of in-hospital mortality remains important for medical groups to target interventions for these patients.The purpose of this study was to identify predictive factors of in-hospital mortality in ventilated ICU patients with an admission diagnosis of acute respiratory failure.We conducted a prospective cohort study in 3 medical ICUs in a 3600-bed university hospital. Consecutive patients with acute respiratory failure who received mechanical ventilation (MV) for at least 96 hours without evidence of pre-existing neuromuscular diseases were followed until discharge. Upon inclusion, the following parameters were collected or evaluated: demographics, clinical history (admission body mass index [BMI], etiology of acute respiratory failure, comorbidity, Charlson comorbidity index, laboratory data), Acute Physiology and Chronic Health Evaluation (APACHE) II, and right and left quadriceps femoris muscle force. The days of MV before extubation, ICU length of stay, survival status at discharge, and hospital length of stay were recorded from the hospital discharge summary. The primary endpoint was in-hospital mortality.In all, 113 patients (65.49% males) were recruited with a mean age of 69.78 years and mean APACHE II score of 22.63. The mean ICU length of stay was 14.88 ± 9.79 days. Overall in-hospital mortality was 25.66% (29 out of 113 patients). Multivariate analysis showed that the essential factors associated with increased in-hospital mortality were lower BMI (P = .013), and lower scores on the right or left quadriceps femoris muscle force (P = .002 and .010, respectively).Our study suggests that lower BMI and lower scores on lower limb muscle force may be associated with increased in-hospital mortality in ventilated ICU patients.

Effects that passive cycling exercise have on muscle strength, duration of mechanical ventilation, and length of hospital stay in critically ill patients: a randomized clinical trial

Objective

To evaluate the effects that passive cycling exercise, in combination with conventional physical therapy, have on peripheral muscle strength, duration of mechanical ventilation, and length of hospital stay in critically ill patients admitted to the ICU of a tertiary care university hospital.

Methods

This was a randomized clinical trial involving 38 patients (≥ 18 years of age) on mechanical ventilation who were randomly divided into two groups: control (n = 16), receiving conventional physical therapy; and intervention (n = 22), receiving conventional physical therapy and engaging in passive cycling exercise five days per week. The mean age of the patients was 46.42 ± 16.25 years, and 23 were male. The outcomes studied were peripheral muscle strength, as measured by the Medical Research Council scale, duration of mechanical ventilation, and length of hospital stay.

Results

There was a significant increase in peripheral muscle strength (baseline vs. final) in both groups (control: 40.81 ± 7.68 vs. 45.00 ± 6.89; and intervention: 38.73 ± 11.11 vs. 47.18 ± 8.75; p < 0.001 for both). However, the range of increase in strength was higher in the intervention group than in the control group (8.45 ± 5.20 vs. 4.18 ± 2.63; p = 0.005). There were no significant differences between the groups in terms of duration of mechanical ventilation or length of hospital stay.

Conclusions

The results suggest that the performance of continuous passive mobilization on a cyclical basis helps to recover peripheral muscle strength in ICU patients. (ClinicalTrials.gov Identifier: NCT01769846 [http://www.clinicaltrials.gov/]).

Can Sarcopenia Quantified by Ultrasound of the Rectus Femoris Muscle Predict Adverse Outcome of Surgical Intensive Care Unit Patients as well as Frailty? A Prospective, Observational Cohort Study

OBJECTIVE

To compare sarcopenia and frailty for outcome prediction in surgical intensive care unit (SICU) patients.

BACKGROUND

Frailty has been associated with adverse outcomes and describes a status of muscle weakness and decreased physiological reserve leading to increased vulnerability to stressors. However, frailty assessment depends on patient cooperation. Sarcopenia can be quantified by ultrasound and the predictive value of sarcopenia at SICU admission for adverse outcome has not been defined.

METHODS

We conducted a prospective, observational study of SICU patients. Sarcopenia was diagnosed by ultrasound measurement of rectus femoris cross-sectional area. Frailty was diagnosed by the Frailty Index Questionnaire based on 50 variables. Relationship between variables and outcomes was assessed by multivariable regression analysis NCT02270502.

RESULTS

Sarcopenia and frailty were quantified in 102 patients and observed in 43.1% and 38.2%, respectively. Sarcopenia predicted adverse discharge disposition (discharge to nursing facility or in-hospital mortality, odds ratio 7.49; 95% confidence interval 1.47-38.24; P = 0.015) independent of important clinical covariates, as did frailty (odds ratio 8.01; 95% confidence interval 1.82-35.27; P = 0.006); predictive ability did not differ between sarcopenia and frailty prediction model, reflected by χ values of 21.74 versus 23.44, respectively, and a net reclassification improvement (NRI) of -0.02 (P = 0.87). Sarcopenia and frailty predicted hospital length of stay and the frailty model had a moderately better predictive accuracy for this outcome.

CONCLUSIONS

Bedside diagnosis of sarcopenia by ultrasound predicts adverse discharge disposition in SICU patients equally well as frailty. Sarcopenia assessed by ultrasound may be utilized as rapid beside modality for risk stratification of critically ill patients.

Muscle Weakness and 5-Year Survival in Acute Respiratory Distress Syndrome Survivors

OBJECTIVES

To longitudinally evaluate the association of post-ICU muscle weakness and associated trajectories of weakness over time with 5-year survival.

DESIGN

Longitudinal prospective cohort study over 5 years of follow-up.

SETTING

Thirteen ICUs in four hospitals in Baltimore, MD.

PATIENTS

One hundred fifty-six acute respiratory distress syndrome survivors.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Strength was evaluated with standardized manual muscle testing using the Medical Research Council sum score (range, 0-60; higher is better), with post-ICU weakness defined as sum score less than 48. Muscle strength was assessed at hospital discharge and at 3, 6, 12, 24, 36, and 48 months after acute respiratory distress syndrome. At discharge, 38% of patients had muscle weakness. Every one point increase in sum score at discharge was associated with improved survival (hazard ratio [95% CI], 0.96 [0.94-0.98]), with similar findings longitudinally (0.95 [0.93-0.98]). Having weakness at discharge was associated with worse 5-year survival (1.75 [1.01-3.03]), but the association was attenuated (1.54 [0.82-2.89]) when evaluated longitudinally over follow-up. Persisting and resolving trajectories of muscle weakness, occurring in 50% of patients during follow-up, were associated with worse survival (3.01 [1.12-8.04]; and 3.14 [1.40-7.03], respectively) compared to a trajectory of maintaining no muscle weakness.

CONCLUSIONS

At hospital discharge, greater than one third of acute respiratory distress syndrome survivors had muscle weakness. Greater strength at discharge and throughout follow-up was associated with improved 5-year survival. In patients with post-ICU weakness, both persisting and resolving trajectories were commonly experienced and associated with worse survival during follow-up.

Prognosis of neurologic complications in critical illness

Neurologic complications of critical illness require extensive clinical and neurophysiologic evaluation to establish a reliable prognosis. Many sequelae of intensive care unit (ICU) treatment, such as delirium and ICU-acquired weakness, although highly associated with adverse outcomes, are less suitable for prognostication, but should rather prompt clinicians to seek previously unnoticed persisting underlying illnesses. Prognostication can be confounded by drug administration particularly because its clearance is abnormal in critical illness. Some neurological complications are severe, and can last for months or years after discharge from ICU. The most important ethical aspects regarding neurologic complications in critically ill patients are prevention, recognition, and identification, and prevention of self-fulfilling prophecies. This chapter summarizes the tool of prognostication of major neurological complications of critical illness.

[Physiotherapy interventions in the ICU : Outcome-relevant measurement parameters]

BACKGROUND

Guidelines cannot provide differentiated recommendations for physiotherapy (PT) in intensive care medicine. Scientific publications for PT in the intensive care unit (ICU) usually only have low levels of evidence and often express safety and feasibility of PT in the ICU.

OBJECTIVE

Which measurement parameters are relevant for defining outcome and what interventions should one take into consideration?

MATERIALS AND METHODS

A literature review was conducted. This was based on a PubMed search with full text access, as well as specific definitions for physical therapy, intensive care and four out of seven conditions from the manual "Physiotherapy in intensive care".

RESULTS

The availability of 172 studies clearly shows that there is certainly PT research concerning the critical environment of the ICU. However, parameters for quantitative and qualitative detection of vigilance and state of consciousness as well as assessments to evaluate the mobility and the ability to help themselves are important for everyday use.

CONCLUSIONS

The difficulties of using PT in the ICU are not useful in ensuring the safety of the patient or performing a PT treatment. The conditions of the intensive care environment are not an obstacle. It is of immanent importance to use the limited resources of PT in an optimal and targeted manner in the ICU environment. The determination of ICU-adapted goals plays a crucial role.

Educational Level Is Related to Physical Fitness in Patients with Type 2 Diabetes - A Cross-Sectional Study

Introduction

Low educational level (EL) and low physical fitness are both predictors of increased morbidity and mortality in patients with type 2 diabetes. It is unknown if EL is related to physical fitness. This would have important implication for the treatment approach of patients of low EL.

Materials and Methods

In 2011/12, we invited participants of a new nationwide Swiss physical activity program for patients with type 2 diabetes to participate in this study. EL was defined by self-report and categorized as low (mandatory education), middle (professional education) or high (high school/university). Physical fitness was determined using 5 validated measures that assessed aerobic fitness, functional lower limb muscle strength, walking speed, balance and flexibility. Potential confounder variables such as other socio-cultural factors, physical activity level, body composition, diabetes-related parameters and complications/co-morbidities as well as well-being were assessed.

Results

All invited 185 participants (mean age 59.6 ±9.8 yrs, 76 women) agreed to be included. Of all patients, 23.1% had a low, 32.7% a middle and 44.2% a high EL; 41.8% were professionally active. The study population had a mean BMI of 32.4±5.2 kg/m² and an HbA1c of 7.3±1.3%. The mean diabetes duration was 8.8±7.4 years. In the baseline assessment, higher EL was associated with increased aerobic fitness, increased functional lower limb muscle strength, and increased walking speed using linear regression analysis (values for low, middle and high EL, respectively: 91.8 ± 27.9, 116.4 ± 49.7 and 134.9 ± 60.4 watts for aerobic fitness (p = 0.002), 15 ± 4.7, 13.9 ± 2.7, 12.6 ± 2.9 seconds for strength (p = 0.001) and 8.8 ± 1.6, 8.3 ± 1.4, 7.8 ± 1.4 seconds for walking speed (p = 0.004)). These associations were independent of potential confounders. Overall, aerobic fitness was 46%, functional limb muscle strength 16%, and walking speed 11% higher in patients of high compared to those of low EL. EL was not related to balance or flexibility.

Discussion

A main strength of the present study is that it addresses a population of importance and a factor (EL) whose understanding can influence future interventions. A second strength is its relatively large sample size of a high-risk population. Third, unlike studies that have shown an association between self-reported fitness and educational level we assessed physical fitness measures by a quantitative and validated test battery using assessors blinded to other data. Another novelty is the extensive evaluation of the role of many relevant confounder variables.

Conclusions

In conclusion, we show that in patients with type 2 diabetes EL correlates favorably and independently with important health-related physical fitness measures such as aerobic fitness, walking speed, and lower limb strength. Our findings underline that diabetic patients with low EL should be specifically encouraged to participate in physical activity intervention programs to further reduce social disparities in healthcare. Such programs should be structured and integrate the norms, needs and capacities (financial, time, physical capacities and self-efficacy) of this population, and their effectiveness should be tested in future studies.

Trial Registration

University of Lausanne clinicaltrials.gov NCT01289587

Measurement of muscle strength with handheld dynamometer in Intensive Care Unit

BACKGROUND

Intensive Care Unit (ICU) acquired weakness is a common complication in critically ill patients affecting their prognosis. The handheld dynamometry is an objective method in detecting minimum muscle strength change, which has an impact on the physical function of ICU survivors. The minimal change in the force can be measured in units of weight such as pounds or kilograms.

AIM OF THE STUDY

To detect the changes in peripheral muscle strength with handheld dynamometer in the early stage of ICU stay and to observe the progression of muscle weakness.

METHODOLOGY

Three upper and three lower limb muscles force measured with handheld dynamometer during ICU stay. Data were analyzed using repeated measures ANOVA to detect changes in force generated by muscle on alternate days of ICU stay.

RESULTS

There was a reduction in peripheral muscle strength from day 3 to day 5 as well from day 5 to day 7 of ICU stay (P < 0.01). The average reduction in peripheral muscle strength was 11.8% during ICU stay.

CONCLUSION

This study showed a progressive reduction in peripheral muscle strength as measured by handheld dynamometer during early period of ICU stay.

Acquired Muscle Weakness in the Surgical Intensive Care Unit

Muscle weakness is common in the surgical intensive care unit (ICU). Low muscle mass at ICU admission is a significant predictor of adverse outcomes. The consequences of ICU-acquired muscle weakness depend on the underlying mechanism. Temporary drug-induced weakness when properly managed may not affect outcome. Severe perioperative acquired weakness that is associated with adverse outcomes (prolonged mechanical ventilation, increases in ICU length of stay, and mortality) occurs with persistent (time frame: days) activation of protein degradation pathways, decreases in the drive to the skeletal muscle, and impaired muscular homeostasis. ICU-acquired muscle weakness can be prevented by early treatment of the underlying disease, goal-directed therapy, restrictive use of immobilizing medications, optimal nutrition, activating ventilatory modes, early rehabilitation, and preventive drug therapy. In this article, the authors review the nosology, epidemiology, diagnosis, and prevention of ICU-acquired weakness in surgical ICU patients.

Physical Function and Disability After Acute Care and Critical Illness Hospitalizations in a Prospective Cohort of Older Adults

OBJECTIVES

To investigate associations between acute care and critical illness hospitalizations and performance on physical functional measures and activities of daily living (ADLs).

DESIGN

Prospective cohort study.

SETTING

Large health maintenance organization.

PARTICIPANTS

Two thousand nine hundred twenty-six participants in Adult Changes in Thought, a study of aging enrolling dementia-free individuals aged 65 and older not living in a nursing home from 1994 to September 30, 2008 (N = 2,926).

MEASUREMENTS

The exposure of interest was hospitalization during study participation, subdivided by presence of critical illness. Outcomes included gait speed, grip strength, chair stand speed, and difficulty and dependence in performing ADLs measured at biennial visits.

RESULTS

Median time between hospital discharge and the next study visit was 311 days (interquartile range (IQR) 151-501 days) after acute care hospitalization and 359 days (IQR 181-420 days) after critical illness hospitalization. Gait speed was slower after acute care (-0.05 m/s, 95% confidence interval (CI) = 0.01-0.04 m/s slower, P < .001) and critical illness (-0.16 m/s, 95% CI = -0.22 to -0.10, P < .001). Grip was weaker after acute care hospitalization (-0.8 kg, 95% CI = -1.0 to -0.6, P < .001) but not significantly different after critical illness hospitalization. Chair-stand speed was slower after acute care hospitalization (-0.04 stands/s, 95% CVI = -0.05 to -0.04, P < .001) and critical illness hospitalization (-0.09, 95% CI = -0.15 to -0.03, P = .003). The odds of difficulty with (odds ratio (OR) = 1.4, 95% CI = 1.2-1.6, P < .001) or dependence in (OR = 2.0, 95% CI = 1.2-3.2, P = .006) one or more ADLs was higher after acute care hospitalization, as were the odds of difficulty with (OR = 1.9, 95% CI = 1.1-3.6, P = .03) or dependence in (OR = 7.9, 95% CI = 2.5-25.7, P = .001) one or more ADLs after critical illness.

CONCLUSION

In older adults, hospitalization, especially for critical illness, was associated with clinically relevant decline in gait and chair stand speed and strongly associated with difficulty with and dependence in ADLs.

Feasibility and Reliability of Muscle Strength Testing in Critically Ill Children

Diagnosing pediatric intensive care unit-acquired weakness (PICU-AW) is challenging. The Medical Research Council (MRC) score is a widely used screening method for muscle weakness in critically ill adults; however, its utility in critically ill children has not been established. Our objective was to determine the feasibility and interobserver reliability of muscle strength testing using MRC score in critically ill children. A prospective observational substudy of critically ill children aged 1 to 17 years and limited to bed rest during the first 48 hours of PICU admission was evaluated with weekly MRC exams independently performed by two clinical raters. MRC exams were attempted on all 33 participants, but could be completed in only 21 (64%), 9 of who (43%) received at least one exam while in the PICU, and in the remaining 12 (57%), MRC exams could only be completed after PICU discharge. Of the 95 attempted MRC exams, 55 (57%) could not be conducted or completed, most commonly due to patient sedation, and inability to comply due to cognitive ability, pain, or noncooperation. The inter-rater reliability for MRC sum score was excellent (intraclass correlation coefficient: 0.87). However, the inter-rater reliability was only moderate when used to determine PICU-AW (Cohen kappa: 0.48). MRC testing in the PICU was not feasible as an early screening tool for muscle weakness in the majority of critically ill children in this study. Further research is needed to find an appropriate screening tool that is both feasible and predicts clinically relevant outcomes in children, such as function and recovery following critical illness.

Muscular strength as a strong predictor of mortality: A narrative review

Muscular strength, an important component of physical fitness, has an independent role in the prevention of chronic diseases whereas muscular weakness is strongly related to functional limitations and physical disability. Our purpose was to investigate the role of muscular strength as a predictor of mortality in health and disease. We conducted a systematic search in EMBASE and MEDLINE (1980-2014) looking for the association between muscular strength and mortality risk (all-cause and cause-specific mortality). Selected publications included 23 papers (15 epidemiological and 8 clinical studies). Muscular strength was inversely and independently associated with all-cause mortality even after adjusting for several confounders including the levels of physical activity or even cardiorespiratory fitness. The same pattern was observed for cardiovascular mortality; however more research is needed due to the few available data. The existed studies failed to show that low muscular strength is predictive of cancer mortality. Furthermore, a strong and inverse association of muscular strength with all-cause mortality has also been confirmed in several clinical populations such as cardiovascular disease, peripheral artery disease, cancer, renal failure, chronic obstructive pulmonary disease, rheumatoid arthritis and patients with critical illness. However, future studies are needed to further establish the current evidence and to explore the exact independent mechanisms of muscular strength in relation to mortality. Muscular strength as a modifiable risk factor would be of great interest from a public health perspective.

Early mobilization and recovery in mechanically ventilated patients in the ICU: a bi-national, multi-centre, prospective cohort study

Introduction

The aim of this study was to investigate current mobilization practice, strength at ICU discharge and functional recovery at 6 months among mechanically ventilated ICU patients.

Method

This was a prospective, multi-centre, cohort study conducted in twelve ICUs in Australia and New Zealand. Patients were previously functionally independent and expected to be ventilated for >48 hours. We measured mobilization during invasive ventilation, sedation depth using the Richmond Agitation and Sedation Scale (RASS), co-interventions, duration of mechanical ventilation, ICU-acquired weakness (ICUAW) at ICU discharge, mortality at day 90, and 6-month functional recovery including return to work.

Results

We studied 192 patients (mean age 58.1 ± 15.8 years; mean Acute Physiology and Chronic Health Evaluation (APACHE) (IQR) II score, 18.0 (14 to 24)). Mortality at day 90 was 26.6% (51/192). Over 1,351 study days, we collected information during 1,288 planned early mobilization episodes in patients on mechanical ventilation for the first 14 days or until extubation (whichever occurred first). We recorded the highest level of early mobilization. Despite the presence of dedicated physical therapy staff, no mobilization occurred in 1,079 (84%) of these episodes. Where mobilization occurred, the maximum levels of mobilization were exercises in bed (N = 94, 7%), standing at the bed side (N = 11, 0.9%) or walking (N = 26, 2%). On day three, all patients who were mobilized were mechanically ventilated via an endotracheal tube (N = 10), whereas by day five 50% of the patients mobilized were mechanically ventilated via a tracheostomy tube (N = 18).

In 94 of the 156 ICU survivors, strength was assessed at ICU discharge and 48 (52%) had ICU-acquired weakness (Medical Research Council Manual Muscle Test Sum Score (MRC-SS) score <48/60). The MRC-SS score was higher in those patients who mobilized while mechanically ventilated (50.0 ± 11.2 versus 42.0 ± 10.8, P = 0.003). Patients who survived to ICU discharge but who had died by day 90 had a mean MRC score of 28.9 ± 13.2 compared with 44.9 ± 11.4 for day-90 survivors (P <0.0001).

Conclusions

Early mobilization of patients receiving mechanical ventilation was uncommon. More than 50% of patients discharged from the ICU had developed ICU-acquired weakness, which was associated with death between ICU discharge and day-90.

Clinical trial registration

ClinicalTrials.gov NCT01674608. Registered 14 August 2012.

A new two-tier strength assessment approach to the diagnosis of weakness in intensive care: an observational study

INTRODUCTION

Intensive care unit-acquired weakness (ICU-AW) is a significant problem. There is currently widespread variability in the methods used for manual muscle testing and handgrip dynamometry (HGD) to diagnose ICU-AW. This study was conducted in two parts. The aims of this study were: to determine the inter-rater reliability and agreement of manual muscle strength testing using both isometric and through-range techniques using the Medical Research Council sum score and a new four-point scale, and to examine the validity of HGD and determine a cutoff score for the diagnosis of ICU-AW for the new four-point scale.

METHODS

Part one involved evaluation of muscle strength by two physical therapists in 29 patients ventilated >48 hours. Manual strength testing was performed by both physical therapists using two techniques: isometric and through range; and two scoring systems: traditional six-point Medical Research Council scale and a new collapsed four-point scale. Part two involved assessment of handgrip strength conducted on 60 patients. A cutoff score for ICU-AW was identified for the new four-point scoring system.

RESULTS

The incidence of ICU-AW was 42% (n = 25/60) in this study (based on HGD). In part one the highest reliability and agreement was observed for the isometric technique using the four-point scale (intraclass correlation coefficient = 0.90: kappa = 0.72 respectively). Differences existed between isometric and through-range scores (mean difference = 1.76 points, P = 0.005). In part two, HGD had a sensitivity of 0.88 and specificity of 0.80 for diagnosing ICU-AW. A cutoff score of 24 out of 36 points was identified for the four-point scale.

CONCLUSIONS

The isometric technique is recommended with reporting on a collapsed four-point scale. Because HGD is easy to perform and sensitive, we recommend a new two-tier approach to diagnosing ICU-AW that first tests handgrip strength with follow-up strength assessment using the isometric technique for muscle strength testing if handgrip strength falls below cutoff scores. Whilst our results for the four-point scale are encouraging, further research is required to confirm the findings of this study and determine the validity of the four-point scoring system and cutoff score developed of less than 24 out of 36 before recommending adoption into clinical practice.

Assessment of impairment and activity limitations in the critically ill: a systematic review of measurement instruments and their clinimetric properties

PURPOSE

To identify measures used to evaluate the broad constructs of functional impairment and limitations in the critically ill across the continuum of recovery, and to evaluate, synthesise and compare the clinimetric properties of the measures identified.

METHODS

A systematic review of articles was carried out using the databases Medline (1950-2014), CINAHL (1982-2014), EMBASE (1980-2014), Cochrane Library (2014) and Scopus (1960-2014). Additional studies were identified by searching personal files. Eligibility criteria for selection: Search 1: studies which assessed muscle mass, strength or function using objective non-laboratory measures; Search 2: studies which evaluated a clinimetric property (reliability, measurement error, validity or responsiveness) for one of the measures identified in search one. Two independent reviewers assessed articles for inclusion and assessed risk of bias using the consensus-based standards for selection of health status measurement instruments checklist.

RESULTS

Thirty-three measures were identified; however, only 20 had established clinimetric properties. Ultrasonography, dynamometry, physical function in intensive care test scored and the Chelsea critical care physical assessment tool performed the strongest for the measurement of impairment of body systems (muscle mass and strength) and activity limitations (physical function), respectively.

CONCLUSIONS

There is considerable variability in the type of measures utilized to measure physical impairments and limitations in survivors of critical illness. Future work should identify a core set of standardized measures, which can be utilized across the continuum of critical illness recovery embedded within the International Classification of Functioning framework. This will enable improved comparisons between future studies, which in turn will assist in identifying the most effective treatment strategies to ameliorate the devastating longer-term outcomes of a critical illness.

[Physical activity diminishes aging-related decline of physical and cognitive performance]

Aging-related decline of muscle force, walking speed, locomotor coordination, aerobic capacity and endurance exert prognostic impact on life expectancy. Proper use of training may diminish the aging process and it may improve the quality of life of elderly persons. This paper provides a brief summary on the impact of training on aging-related decline of physical and cognitive functions.

Cut points of muscle strength associated with metabolic syndrome in men

INTRODUCTION

The loss of muscle strength with age increases the likelihood of chronic conditions, including metabolic syndrome (MetS). However, the minimal threshold of muscle strength at which the risk for MetS increases has never been established.

OBJECTIVE

This study aimed to identify a threshold of muscle strength associated with MetS in men.

METHODS

We created receiver operating curves for muscle strength and the risk of MetS from a cross-sectional sample of 5685 men age <50 yr and 1541 men age ≥50 yr enrolled in the Aerobics Center Longitudinal Study. The primary outcome measure, the MetS, was defined according to the National Cholesterol Education Program Adult Treatment Panel III criteria. Upper and lower body muscle strength was treated as a composite measure of one-repetition maximum tests on bench and leg press and scaled to body weight. Low muscle strength was defined as the lowest age-specific 20th percentile, whereas high muscle strength was defined as composite muscle strength above the 20th percentile.

RESULTS

In men aged <50 yr, the odds of MetS were 2.20-fold (95% confidence interval = 1.89-2.54) higher in those with low muscle strength, independent of age, smoking, and alcohol intake. The strength of this association was similar for men age ≥50 yr (odds ratio = 2.11, 95% confidence interval = 1.62-2.74). In men age < 50 yr, the composite strength threshold associated with MetS was 2.57 kg·kg body weight, whereas in men age ≥ 50 yr the threshold was 2.35 kg·kg body weight.

CONCLUSION

This study is the first to identify a threshold of muscle strength associated with an increased likelihood of MetS in men. Measures of muscle strength may help identify men at risk of chronic disease.

Assessment of limb muscle strength in critically ill patients: a systematic review

OBJECTIVES

To determine the reliability of volitional and nonvolitional limb muscle strength assessment in critically ill patients and to provide guidelines for the implementation of limb muscle strength assessment this population.

DATA SOURCES

The following computerized bibliographic databases were searched with MeSH terms and keywords or combinations: MEDLINE through PubMed and Embase through Embase.com.

STUDY SELECTION

Articles were screened by two independent reviewers. Included studies were all performed in humans and were original articles. The research population exists of adult, critically ill patients or ICU survivors of either sex, and those admitted to a medical, surgical, respiratory, or mixed ICU. A study was included if reliability of muscle strength measurements was determined in this population.

DATA EXTRACTION

Data on baseline characteristics (country, study population, eligibility, age, setting and method, and equipment of limb muscle strength assessment) and reliability scores were obtained by two independent reviewers.

DATA SYNTHESIS

Data of six observational studies were analyzed. Interrater reliability of the Medical Research Council scale for individual muscle groups varied from "fair" or "substantial" (weighted κ, 0.23-0.64) to "very good" agreement (weighted κ, 0.80-0.96). Interrater reliability of the Medical Research Council-sum score was found to be very good in all four studies (intraclass correlation coefficients, 0.86-0.99 or Pearson product moment correlation coefficient = 0.96). Interrater reliability of handheld dynamometry was comparable between two studies (intraclass correlation coefficients, 0.62-0.96). Interrater reliability of handgrip dynamometry was very good in two studies (intraclass correlation coefficients, 0.89-0.97). Intrarater reliability of handheld dynamometry and handgrip dynamometry was assessed in one study, and results were very good (intraclass correlation coefficients > 0.81). No studies were obtained on reliability of nonvolitional muscle strength assessment.

CONCLUSIONS

Voluntary muscle strength measurement has proven reliable in critically ill patients provided that strict guidelines on adequacy and standardized test procedures and positions are followed.

Muscle weakness predicts pharyngeal dysfunction and symptomatic aspiration in long-term ventilated patients

BACKGROUND

Prolonged mechanical ventilation is associated with muscle weakness, pharyngeal dysfunction, and symptomatic aspiration. The authors hypothesized that muscle strength measurements can be used to predict pharyngeal dysfunction (endoscopic evaluation-primary hypothesis), as well as symptomatic aspiration occurring during a 3-month follow-up period.

METHODS

Thirty long-term ventilated patients admitted in two intensive care units at Massachusetts General Hospital were included. The authors conducted a fiberoptic endoscopic evaluation of swallowing and measured muscle strength using medical research council score within 24 h of each fiberoptic endoscopic evaluation of swallowing. A medical research council score less than 48 was considered clinically meaningful muscle weakness. A retrospective chart review was conducted to identify symptomatic aspiration events.

RESULTS

Muscle weakness predicted pharyngeal dysfunction, defined as either valleculae and pyriform sinus residue scale of more than 1, or penetration aspiration scale of more than 1. Area under the curve of the receiver-operating curves for muscle strength (medical research council score) to predict pharyngeal, valleculae, and pyriform sinus residue scale of more than 1, penetration aspiration scale of more than 1, and symptomatic aspiration were 0.77 (95% CI, 0.63-0.97; P = 0.012), 0.79 (95% CI, 0.56-1; P = 0.02), and 0.74 (95% CI, 0.56-0.93; P = 0.02), respectively. Seventy percent of patients with muscle weakness showed symptomatic aspiration events. Muscle weakness was associated with an almost 10-fold increase in the symptomatic aspiration risk (odds ratio = 9.8; 95% CI, 1.6-60; P = 0.009).

CONCLUSION

In critically ill patients, muscle weakness is an independent predictor of pharyngeal dysfunction and symptomatic aspiration. Manual muscle strength testing may help identify patients at risk of symptomatic aspiration.

Surgical Intensive Care Unit Optimal Mobilisation Score (SOMS) trial: a protocol for an international, multicentre, randomised controlled trial focused on goal-directed early mobilisation of surgical ICU patients

INTRODUCTION

Immobilisation in the intensive care unit (ICU) leads to muscle weakness and is associated with increased costs and long-term functional disability. Previous studies showed early mobilisation of medical ICU patients improves clinical outcomes. The Surgical ICU Optimal Mobilisation Score (SOMS) trial aims to test whether a budget-neutral intervention to facilitate goal-directed early mobilisation in the surgical ICU improves participant mobilisation and associated clinical outcomes.

METHODS AND ANALYSIS

The SOMS trial is an international, multicentre, randomised clinical study being conducted in the USA and Europe. We are targeting 200 patients. The primary outcome is average daily SOMS level and key secondary outcomes are ICU length of stay until discharge readiness and 'mini' modified Functional Independence Measure (mmFIM) at hospital discharge. Additional secondary outcomes include quality of life assessed at 3 months after hospital discharge and global muscle strength at ICU discharge. Exploratory outcomes will include: ventilator-free days, ICU and hospital length of stay and 3-month mortality. We will explore genetic influences on the effectiveness of early mobilisation and centre-specific effects of early mobilisation on outcomes.

ETHICS AND DISSEMINATION

Following Institutional Review Board (IRB) approval in three institutions, we started study recruitment and plan to expand to additional centres in Germany and Italy. Safety monitoring will be the domain of the Data and Safety Monitoring Board (DSMB). The SOMS trial will also explore the feasibility of a transcontinental study on early mobilisation in the surgical ICU.

RESULTS

The results of this study, along with those of ancillary studies, will be made available in the form of manuscripts and presentations at national and international meetings.

REGISTRATION

This study has been registered at clinicaltrials.gov (NCT01363102).

Issues affecting the delivery of physical therapy services for individuals with critical illness

Research supports the provision of physical therapy intervention and early mobilization in the management of patients with critical illness. However, the translation of care from that of well-controlled research protocols to routine practice can be challenging and warrants further study. Discussions in the critical care and physical therapy communities, as well as in the published literature, are investigating factors related to early mobilization such as transforming culture in the intensive care unit (ICU), encouraging interprofessional collaboration, coordinating sedation interruption with mobility sessions, and determining the rehabilitation modalities that will most significantly improve patient outcomes. Some variables, however, need to be investigated and addressed specifically by the physical therapy profession. They include assessing and increasing physical therapist competence managing patients with critical illness in both professional (entry-level) education programs and clinical settings, determining and providing an adequate number of physical therapists for a given ICU, evaluating methods of prioritization of patients in the acute care setting, and adding to the body of research to support specific functional outcome measures to be used with patients in the ICU. Additionally, because persistent weakness and functional limitations can exist long after the critical illness itself has resolved, there is a need for increased awareness and involvement of physical therapists in all settings of practice, including outpatient clinics. The purpose of this article is to explore the issues that the physical therapy profession needs to address as the rehabilitation management of the patient with critical illness evolves.