Inspiratory muscle weakness is common among mechanically ventilated patients and is a well-recognized contributor to weaning difficulties, which are associated with poor outcomes and increased mortality. Inspiratory muscle training is a feasible and promising intervention that can improve global respiratory muscle strength and potentially facilitate successful liberation from mechanical ventilation in patients with weaning difficulties. This article proposes a practical guide supporting clinicians in integrating inspiratory muscle training into the care of mechanically ventilated patients experiencing weaning difficulties, informed by clinical experience and current evidence. The proposed approach focuses on the application of inspiratory muscle training in patients with weaning difficulties (mostly tracheostomized patients undergoing prolonged weaning), who fulfill readiness-to-wean criteria and are fully cooperative. Training sessions are typically conducted daily while the patient is disconnected from the ventilator, following an initial assessment of maximal inspiratory pressure and forced vital capacity. These parameters, along with volume displacement observed during each training session and symptom scores evaluated afterward, are used to individualize the initial external load and training progression. The main components that are taken into account to offer and individualize the training approach include patient selection, respiratory muscle and lung function assessment, load setting modalities, breathing instructions during training, and training progression guided by symptom scores and volume displacement.

BACKGROUND:Recent studies suggest that fast and deep inspirations against either low or high external loads may provide patients with weaning difficulties with a training stimulus during inspiratory muscle training (IMT). However, the relationship between external IMT load, reflected by changes in airway pressure swings (ΔPaw), and total inspiratory effort, measured by oesophageal pressure swings (ΔPes), remains unexplored. Additionally, the association between ΔPes, ΔPaw, and inspiratory muscle activations remains unclear. OBJECTIVES:The ai of this study was to compare ΔPes and ΔPaw and their relationship with inspiratory muscle activation in patients with weaning difficulties during different breathing conditions. METHODS:ΔPes and scalene, sternocleidomastoid, and parasternal intercostal muscles activation were recorded during the following conditions: 1) (proportional) pressure support ventilation; 2) unsupported spontaneous breathing; 3) low-load IMT (load: <10% maximal inspiratory pressure, PImax = 3 cmH2O) executed with slow and deep inspirations (low-load slow) and 4) low-load IMT (load: <10% maximal inspiratory pressure, PImax = 3 cmH2O) executed with fast deep inspirations (low-load fast); and 5) high-load IMT (load ∼ 30% PImax) executed with fast and deep inspirations. ΔPaw, end-inspiratory lung volume, and peak inspiratory flow were recorded during conditions 2-5. Variables were compared across conditions using mixed-model analysis. Spearman's rank correlations were calculated between inspiratory muscle activations and both ΔPes and ΔPaw. RESULTS:Five patients (age: 68 ± 1 y; 20% male; PImax: 37 ± 7 cmH2O [59 ± 23% predicted]; forced vital capacity: 0.66 ± 0.16 L [21 ± 6% predicted]) were included in the study. ΔPes values were 3-4 times larger than ΔPaw values during unsupported spontaneous breathing and IMT conditions. ΔPes, sternocleidomastoid activation, end-inspiratory lung volume, and peak inspiratory flow were larger during low-load fast IMT than during low-load slow IMT and unsupported spontaneous breathing but were similar between low-load fast and high-load IMTs. Inspiratory muscle activations correlated weakly to moderately with ΔPaw and moderately with ΔPes. CONCLUSIONS:In five patients with weaning difficulties, low-load fast IMT provided a training stimulus similar to high-load IMT. Both yielded significantly higher training stimulus than low-load slow IMT and unsupported spontaneous breathing. These results should be considered in future trials comparing IMT with sham conditions. CLINICAL TRIAL REGISTRATION NUMBERS:NCT03240263 and NCT04658498.

Rationale: Inspiratory muscle training (IMT) improves respiratory muscle function in patients with weaning difficulties. IMT protocols involve performing daily sets of breaths against external loads. However, the impact of IMT on weaning outcomes while incorporating sham control interventions remains unclear. Objectives: To compare the effects of a high-intensity IMT (Hi-IMT) intervention with a sham low-intensity (Lo-IMT) control group on weaning outcomes and respiratory muscle and pulmonary function 28 days after inclusion in patients with weaning difficulties. Methods: Both groups underwent daily IMT sessions until successful weaning or a maximum of 28 days. The Hi-IMT group (n = 44; 61% male; aged 57 ± 15 yr) performed maximal inspirations initiated from residual volume against an external load representing 30-50% of maximal inspiratory pressure (PImax), and the control group (n = 46; 52% male; aged 60 ± 12 yr) performed maximal inspirations against a load ⩽10% PImax. Measurements and Main Results: Training adherence (completed/planned sessions) was comparable between the groups (Hi-IMT, 77 ± 20%; Lo-IMT, 72 ± 17%; P = 0.25). Weaning success (64% Hi-IMT and 76% Lo-IMT; P = 0.43) and weaning duration (Hi-IMT, 45 ± 48 d; Lo-IMT, 37 ± 26 d; P = 0.33) were similar between groups. Both groups similarly improved PImax (Hi-IMT, +15 cm H2O [95% confidence interval (CI), 9, 20]; Lo-IMT, +14 cm H2O [95% CI, 9, 19]; P = 0.72). FVC improved more in the Hi-IMT group than in the Lo-IMT group (Hi-IMT, +0.33 L [95% CI, 0.22, 0.43]; Lo-IMT, +0.16 L [95% CI, 0.07, 0.25]; P = 0.04). Conclusions: Both high-intensity IMT and sham low-intensity IMT, with high adherence to the protocol, resulted in similar weaning success rates and pronounced improvements in maximal inspiratory muscle strength. Clinical trial registered with www.clinicaltrials.gov (NCT03240263).

Introduction IMT improves respiratory muscle function in patients with weaning difficulties. It is unknown if IMT improves clinical outcomes and respiratory function. Aim Assessing the effect of high-intensity IMT (H-IMT) vs. sham low-intensity IMT (L-IMT) on clinical outcomes and respiratory function in patients with weaning difficulties. Methods Patients performed daily IMT sessions (4sets, 6–10 breaths) until weaning success or 28 days. H-IMT group (n=43, 27%male, age:57±15y) trained at the highest tolerable external load (30-50% maximal inspiratory pressure, PImax) and L-IMT group (n=45, 24%male, age:60±12y) at max.10%PImax. Results Both groups had high weaning success rates. In successfully weaned patients, trends to a shorter weaning duration and ICU stay in the H-IMT than L-IMT group were observed (Table 1). Both improved PImax and vital capacity significantly, with H-IMT yielding greater vital capacity gains. H-IMT improved peak inspiratory flow and rapid shallow breathing index, yet not significantly different from L-IMT. Conclusions Both IMT protocols have similar benefits on weaning outcomes, consistent with prior studies on IMT, yet H-IMT tended to reduce weaning duration and ICU stay. While both improved respiratory muscle function, H-IMT had greater impact on pulmonary function. More studies needed to optimise the IMT protocol and asses internal load impact on inspiratory muscles.

Assessing and treating respiratory muscle dysfunction is crucial for patients with both acute and chronic respiratory failure. Respiratory muscle dysfunction can contribute to the onset of respiratory failure and may also worsen due to interventions aimed at treatment. Evaluating respiratory muscle function is particularly valuable for diagnosing, phenotyping and assessing treatment efficacy in these patients. This review outlines established methods, such as measuring respiratory pressures, and explores novel techniques, including respiratory muscle neurophysiology assessments using electromyography and imaging with ultrasound.Additionally, we review various treatment strategies designed to support and alleviate the burden on overworked respiratory muscles or to enhance their capacity through training interventions. These strategies range from invasive and noninvasive mechanical ventilation approaches to specialised respiratory muscle training programmes. By summarising both established techniques and recent methodological advancements, this review aims to provide a comprehensive overview of the tools available in clinical practice for evaluating and treating respiratory muscle dysfunction. Our goal is to present a clear understanding of the current capabilities and limitations of these diagnostic and therapeutic approaches. Integrating advanced diagnostic methods and innovative treatment strategies should help improve patient management and outcomes. This comprehensive review serves as a resource for clinicians, equipping them with the necessary knowledge to effectively diagnose and treat respiratory muscle dysfunction in both acute and chronic respiratory failure scenarios.

Background: It is unclear if inspiratory effort as assessed by esophageal or airway pressure swings relates with the load set during inspiratory muscle training (IMT) and how the effort is associated with activation (EMG) of inspiratory muscles in DTW patients. Aims: To characterize the relationship between esophageal pressures (ΔPes), airway pressures (ΔPaw) swings and EMG of scalene (EMGsca), sternocleidomastoid (EMGscm) and parasternal intercostal (EMGic) muscles in a DTW patient during unsupported spontaneous breathing (SB), low-load (LL) and high-load (HL) IMT. Methods: A female DTW patient of 66 years with COPD, had a maximal inspiratory pressure of 32cmH2O and a FVC of 820mL. Paw, Pes and EMG signals were continuously recorded during 1min SB and during 2 sets of LL-IMT (external load=3cmH2O) and 2 sets of HL-IMT (external load=9cmH2O). Results: ΔPes were considerably larger than ΔPaw in all conditions (Fig.1A). Both ΔPes and EMG were higher during IMT as compared to spontaneous breathing, but not different between IMT conditions. ΔPes was more strongly associated with EMGsca, EMGscm and EMGic across the different breathing conditions than ΔPaw (Fig.1B-C). Conclusions: In a DTW patient inspiratory effort quantified as ΔPes was 3 to 4 times larger than ΔPaw generated by external loads and better related to activation of extradiaphragmatic inspiratory muscles.

Background: Inspiratory muscle training improves respiratory muscle function and may improve weaning outcomes in patients with weaning difficulties. Compared to the commonly used pressure threshold loading, tapered flow resistive loading better accommodates pressure-volume relationships of the respiratory muscles, which might help to facilitate application of external loads and optimise training responses.Objective: The objective of this study was to compare acute breathing pattern responses and perceived symptoms during an inspiratory muscle training session performed against identical external loading provided as pressure threshold loading or as tapered flow resistive loading. We hypothesised that for a given loading, tapered flow resistive loading would allow larger volume expansion and higher inspiratory flow responses and consequently higher external work of breathing and power than pressure threshold loading and that subsequently patients perceived fewer symptoms during tapered flow resistive loading than during pressure threshold loading. Methods: In this exploratory study, 21 patients (maximal inspiratory pressure: 35 & PLUSMN; 14 cmH2O and vital capacity:0.85 L & PLUSMN;0.37 L) performed two training sessions against external loads equalling 42 & PLUSMN; 15% of maximal inspiratory pressure provided either as pressure threshold loading or as tapered flow resistive loading. During these training sessions, breath-by-breath data of breathing parameters were collected, and patients rated their perceived breathing effort, dyspnoea, and unpleasantness.Results: Compared to pressure threshold loading, tapered flow resistive loading allowed significantly larger volume expansion (0.53 & PLUSMN; 0.28 L versus 0.41 & PLUSMN; 0.20 L, p < 0.01) and inspiratory flow responses (0.43 & PLUSMN; 0.20 L/s versus 0.33 & PLUSMN; 0.16 L/s, p = 0.01). Tapered flow resistive loading was perceived as less unpleasant (3.1 & PLUSMN; 1.9 versus 3.8 & PLUSMN; 2.4, p = 0.048). No significant differences in breathing effort, dyspnoea, work of breathing, and power were observed.Conclusions: For a given loading, inspiratory muscle training with tapered flow resistive loading allowed larger volume expansion and higher inspiratory flow responses than pressure threshold loading, which led patients to perceive tapered flow resistive loading as less unpleasant. This might help us to facilitate early implementation of inspiratory muscle training in patients with weaning difficulties. Clinical trial registration number: Clinicaltrials.gov identifier: NCT03240263 & COPY; 2022 Australian College of Critical Care Nurses Ltd. Published by Elsevier Ltd. All rights reserved.

Background : Tapered flow resistive loading (TFRL) better accommodates the pressure-volume relationships of the inspiratory muscles than the commonly used pressure threshold loading (TL). It is unclear if TFRL elicits different breathing pattern responses compared to TL in patients with weaning difficulties. Aim : Compare acute breathing pattern and perceived symptoms in response to IMT sessions performed against equal initial inspiratory loading provided as either TL or TFRL in patients with weaning difficulties. Method : 21 patients (52±16years) with maximal inspiratory pressure (PImax): 35±14cmH2O and FVC: 0.85L±0.37L, performed two IMT sessions against TL or TFRL with an initial load of 42±15%PImax. Breath-by-breath data of breathing parameters were collected and patients rated their perceived symptoms afterwards. Results : For a given loading, TFRL allowed significantly larger inspiratory tidal volumes and inspiratory flow responses but inspiratory pressure was lower compared to TL. No differences in work of breathing or power were observed between the types of loading. Patients perceived TFRL as less unpleasant (Table 1). Conclusion : For a given loading, TFRL-IMT allows larger volume expansion and higher inspiratory flow responses compared to TL-IMT and patients perceived TFRL as less unpleasant. This might facilitate early implementation of IMT and improve training outcomes in patients with weaning difficulties. ![Figure][1] Footnotes Cite this article as: ERJ Open Research 2022; 8: Suppl. 9, 13. This article was presented at the 2022 ERS Respiratory Failure and Mechanical Ventilation Conference, in session “Poster Session 2”. This is an ERS Respiratory Failure and Mechanical Ventilation Conference abstract. No full-text version is available. Further material to accompany this abstract may be available at [www.ers-education.org][2] (ERS member access only). [1]: pending:yes [2]: http://www.ers-education.org

BackgroundCritically ill patients who have difficulties weaning from the mechanical ventilator are prone to develop respiratory muscle weakness. Inspiratory muscle training (IMT) can improve respiratory muscle strength. Whether IMT can improve scalene and sternocleidomastoid muscle oxygenation parameters is unknown.AimTo compare changes in muscle oxygenation parameters of scalene and sternocleidomastoid inspiratory muscles during a standardized task between patients with weaning difficulties who received either high-intensity IMT (intervention) or sham low-intensity IMT (control).MethodForty-one patients performed daily IMT sessions (4 sets, 6–10 breaths) until weaning success or for 28 consecutive days. The training load was progressively adjusted in the intervention group (n = 22) to the highest tolerable load, whilst the control group (n = 19) kept training at 10% of their baseline maximal inspiratory pressure (PImax). Breathing characteristics (i.e., work and power of breathing, PoB), respiratory muscle function [i.e., PImax and forced vital capacity (FVC)] were measured during a standardized loaded breathing task against a load of 30% of baseline PImax before and after the IMT period. In addition, during the same loaded breathing task, absolute mean and nadir changes from baseline in local scalene and sternocleidomastoid muscle oxygen saturation index (Δ%StiO2) (an index of oxygen extraction) and nadir Δ%StiO2 normalized for the PoB were measured by near-infrared spectroscopy.ResultsAt post measures, only the intervention group improved mean PoB compared to pre measures (Pre: 0.42 ± 0.33 watts, Post: 0.63 ± 0.51watts, p-value < 0.01). At post measures, both groups significantly improved nadir scalene muscles StiO2% normalized for the mean PoB (ΔStiOnadir%/watt) compared to pre measurements and the improvement was not significant different between groups (p-value = 0.40). However, at post measures, nadir sternocleidomastoid muscle StiO2% normalized for the mean PoB (ΔStiOnadir%/watt) was significantly greater improved in the intervention group (mean difference: +18.4, 95%CI: −1.4; 38.1) compared to the control group (mean difference: +3.7, 95%CI: −18.7; 26.0, between group p-value < 0.01). Both groups significantly improved PImax (Intervention: +15 ± 13 cmH2O p-value < 0.01, Control: +13 ± 15 cmH2O p-value < 0.01). FVC only significantly improved in the intervention group (+0.33 ± 0.31 L p < 0.01) report also change in control group.ConclusionThis exploratory study suggests that high-intensity IMT induces greater improvements in scalene and sternocleidomastoid muscle oxygenation parameters attributed for oxygen delivery, utilization and oxygen saturation index compared to low-intensity IMT in patients with weaning difficulties.

Inspiratory muscle training (IMT) improves respiratory muscle function and might enhance weaning outcomes in patients with weaning difficulties. An electronic inspiratory loading device provides valid, automatically processed information on breathing characteristics during IMT sessions. Adherence to and quality of IMT, as reflected by work of breathing and power generated by inspiratory muscles, are related to improvements in inspiratory muscle function in patients with chronic obstructive pulmonary disease. The aim of this study was to investigate the validity of an electronic training device to assess and provide real-time feedback on breathing characteristics during inspiratory muscle training (IMT) in patient with weaning difficulties. Patients with weaning difficulties performed daily IMT sessions against a tapered flow-resistive load of approximately 30 to 50% of the patient’s maximal inspiratory pressure. Airflow and airway pressure measurements were simultaneously collected with the training device (POWERbreatheKH2, POWERbreathe International Ltd, UK) and a portable spirometer (reference device, Pocket-Spiro USB/BT100, M.E.C, Belgium). Breath by breath analysis of 1002 breaths of 27 training sessions (n = 13) against a mean load of 46±16% of the patient’s maximal inspiratory pressure were performed. Good to excellent agreement (Intraclass correlation coefficients: 0.73–0.97) was observed for all breathing characteristics. When individual differences were plotted against mean values of breaths recorded by both devices, small average biases were observed for all breathing characteristics. To conclude, the training device provides valid assessments of breathing characteristics to quantify inspiratory muscle effort (e.g. work of breathing and peak power) during IMT in patients with weaning difficulties. Availability of valid real-time data of breathing responses provided to both the physical therapist and the patient, can be clinically usefull to optimize the training stimulus. By adapting the external load based on the visual feedback of the training device, respiratory muscle work and power generation during IMT can be maximized during the training.

Introduction: Inspiratory muscle training (IMT) improves respiratory muscle function in DTW patients. It is unknown whether IMT affects extradiaphragmatic inspiratory muscle oxygenation and efficiency. Aim: to evaluate the effect of high-intensity IMT versus sham IMT on inspiratory muscle oxygenation and efficiency during a loaded breathing task at 30% of baseline Pimax in DTW patients. Methods: 48 patients (age:57±16y) performed daily IMT sessions (4 sets, 6–10 breaths) until weaning success or for 28 consecutive days. The IMT group trained at the highest possible load (30-50% Pimax) and sham group at 10%Pimax. Work of breathing (WoB) and power of breathing (PoB) were measured and scalene (SCA) and sternocleidomastoid (SCM) oxygen saturation responses were assessed by near-infrared spectroscopy. Muscle efficiency was expressed as change in muscle oxygenation per unit increase in PoB. Results: After the intervention period, both groups significantly improved WoB, and SCA muscle efficiency. Only the IMT group improved PoB, SCA and SCM muscle oxygenation. In addition, only the improvement in SCM muscle efficiency was significantly higher in the IMT group compared to the sham group (Table 1). Conclusions: High intensity IMT as compared to sham training induced greater improvements in SCM efficiency in DTW patients.

Introduction: A recently introduced electronic inspiratory loading device (EILD) provides valid information on breathing characteristics in COPD patients. This has not yet been confirmed in weaning failure patients. Aim: To investigate the measurement validity of this EILD. Method: In 30 patients, 64 training sessions were analysed. Flow and pressure signals of 2594 breaths, against a mean resistance of 24% of the maximal inspiratory pressure, were sampled and processed by the EILD (POWERbreathe KH2, HaB International,UK) and a pulmonary function device (Pocket-Spiro USB/BT 100, M.E.C) which served as gold standard. Result: Small but significant differences in median? breathing characteristics were observed between the devices (Table1). ICC’s were high and average bias small (range: -7to11%; Table1) indicating good to excellent agreement on a group level. However, the EILD missed ~6% of the breaths that could be recorded with the golden standard (fig1.). These missed breaths had significantly lower tidal volume (median: 0,07L) and lower mean inspiratory flow (median 0,12L/s; fig.2). Conclusion: EILD provides valid estimates of breathing characteristics to quantify the load during inspiratory muscle training in weaning failure patients. However, breaths with a very low tidal volume and/or mean inspiratory flow might not always be recorded with the inspiratory loading device.

Summary: The purpose of this study was to compare common techniques of pubic symphyseal fixation with a new method, the "box plate," for fractures of the pelvis where the bone is osteopenic. This symphyseal fixation construct consists of two, two-hole, 4.5-mm narrow dynamic compression plates (DCP) oriented parallel to one another. One plate is recessed within the symphysis, and the other is located on the pubic tubercles. The plates are interlocked using two 6.5-mm fully threaded screws, forming a box-like construct. To determine the mechanical properties of this construct, five fresh, cadaveric pelvic specimens with a mean age of 75 years were harvested. The femora of each specimen were potted into containers and fixed to the base of a materials testing machine. The pelvis was constrained from rotating about the hip joints by anterior and posterior restraints. A vertical compressive load was applied through the lumbar spine. Force to a magnitude of 1,000 N was applied through three cycles. Gapping motions at the symphysis pubis (SP) and the sacroiliac (SI) joints, and flexion-extension of the sacrum with respect to the ilia were measured under the following conditions: (a) intact, (b) SP ligament, unilateral anterior SI ligaments, and ipsilateral sacrospinous and sacrotuberous ligaments disrupted (anteroposterior compression type II injury), and these injuries fixed using (c) a 4.5-mm narrow two-hole DC plate placed on the superior SP held by two cancellous bone screws, (d) the DC plate well as a single 7.0-mm cannulated cancellous iliosacral lag screw across the injured SI joint, (e) the DC plate and a five-hole 3.5-mm reconstruction plate on the anterior SP, (f) a 3.5-mm, four-hole, DC plate on the superior SP using four fully threaded screws, and (g) the box plate symphyseal construct described above. All fixations reduced SP joint gapping compared to the disrupted joint. However, all but the box plate still allowed significantly greater motion than the intact SP joint. No fixation significantly reduced SI joint gapping or sacral flexion compared to the injured state.

PURPOSE:To investigate the effect of Neuromuscular Electrical Stimulation (NMES) on muscle thickness, strength and morphological and molecular markers of the quadriceps. MATERIALS AND METHODS:Adult critically ill patients with an expected prolonged stay received unilateral quadriceps NMES sessions for 7 consecutive days. Before and after the intervention period, quadriceps thickness was measured with ultrasound. After the intervention period, strength was assessed in cooperative patients and muscle biopsies were taken. Multivariable regression was performed to identify factors affecting muscle thickness loss. RESULTS:Muscle thickness decreased less in the stimulated leg (-6 ± 16% versus -12 ± 15%, p = 0.014, n = 47). Strength was comparable. Opioid administration, minimal muscle contraction and more muscle thickness loss in the non-stimulated muscle were independently associated with better muscle thickness preservation. Stimulated muscles showed a shift towards larger myofibers and higher MyHC-I gene expression. NMES did not affect gene expression of other myofibrillary proteins, MuRF-1 or atrogin-1. Signs of myofiber necrosis and inflammation were comparable for both muscles. CONCLUSIONS:NMES attenuated the loss of muscle mass, but not of strength, in critically ill patients. Preservation of muscle mass was more likely in patients receiving opioids, patients with a minimal muscle contraction during NMES and patients more prone to lose muscle mass. TRIAL REGISTRATION:clinicaltrials.govNCT02133300.

The 2018 Paris Intensive Care symposium entitled “Update in Neurocritical Care” was organized in Paris, June 21–22, 2018, under the auspices of the French Intensive Care Society. This 2-day post-graduate educational symposium comprised several chapters, aiming first to provide all-board intensivists with current standards for the clinical assessment of altered consciousness states (including coma and delirium) and peripheral nervous system in critically ill patients, monitoring of brain function (specifically, electro-encephalography) and best practices for sedation—analgesia—delirium management. An update on the treatment of specific severe brain pathologies—including ischaemic/haemorrhagic stroke, cerebral venous thrombosis, hypoxic-ischaemic brain injury, immune-mediated and infectious encephalitis and refractory status epilepticus—was also provided. Finally, we discuss how to approach some difficult decisions, namely the role of decompressive craniectomy and prognostication models in patients with head injury. For each chapter, the scope of the present review was to provide important issues and key messages, provide most recent and relevant literature in the field, and briefly describe new developments in the field.

Introduction: IMT increases inspiratory muscle strength in weaning patients. Whether IMT induces changes in breathing characteristics and inspiratory muscle oxygenation is unknown. Objective: To evaluate the effects of IMT versus SHAM on breathing characteristics and inspiratory muscle oxygenation in difficult to wean patients. Methods: 12 patients [age: 61y (39, 72), Pimax: 30cmH2O (28, 43)] were allocated to an IMT or a SHAM training group. Using TFRL device, groups performed daily training sessions (4 sets, 6–10 breaths) until successful weaning. IMT group trained initially at 30% of baseline Pimax, aiming at reaching 50%Pimax. SHAM group trained at 10%Pimax, not adjustable. Inspiratory flows and pressure, work and pattern of breathing and fractional oxygen saturation of scalene and sternocleidomastoid muscle (by near-infrared spectroscopy) were assessed during a training session at 30% of baseline Pimax, before and after the intervention period. Results: After intervention, IMT group increased inspiratory flow and tidal volume and performed greater work of breathing with less decrease in muscle oxygen saturation as compared to SHAM group (table 1). Conclusion: The interim analysis shows that IMT using TFRL has a positive effect on breathing characteristics and inspiratory muscle oxygenation in weaning patients.

Introduction Respiratory muscle dysfunction has been associated with failure to wean from mechanical ventilation. It has therefore been hypothesised that these patients might benefit from inspiratory muscle training (IMT). Evidence, however, is thus far limited to data from small, single-centre studies with heterogeneity in inclusion criteria, training modalities and outcomes. The aim of this study is to evaluate the effects of a novel IMT method on weaning outcomes in selected patients with weaning difficulties. Methods This study is designed as a double-blind, parallel-group, randomised controlled superiority trial with 1:1 allocation ratio. Patients with weaning difficulties will be randomly allocated into either an IMT group (intervention) or a sham-IMT group (control). Ninetypatients (45 in each group) will be needed to detect a 28% difference in the proportion of weaning success between groups (estimated difference in primary outcome based on previous studies) with a risk for type I error (α) of 5% and statistical power (1-β) of 80%. Patients will perform four sets of 6–10 breaths daily against an external load using a tapered flow resistive loading device (POWERbreathe KH2, HaB International, UK). Training intensity in the intervention group will be adjusted to the highest tolerable load. The control group will train against a low resistance that will not be modified during the training period. Training will becontinued until patients are successfully weaned or for a maximum duration of 28 days. Pulmonary and respiratory muscle function, weaning duration, duration of mechanical ventilation, ventilator-free days and length of stay in the intensive care unit will be evaluated as secondary outcomes. Χ2 tests and analysis of covariance with adjustments for baseline values of respective outcomesas covariates will be used to compare results after the intervention period between groups. Ethics and dissemination Ethics approval was obtained from the local ethical committee (Ethische Commissie Onderzoek UZ/KU Leuven protocol ID: S60516). Results from this randomised controlled trial will be presented at scientific meetings as abstracts for poster or oral presentations and published in peerreviewed journals. Trial status Enrolment into the study have started in August 2017. Data collection and data analysis are expected to be completed in September 2021. Trial registration number NCT03240263 .

ICU-Acquired Weakness is a common complication in CI patients. Muscle wasting occurs early after admission, when the patient is often sedated.NMES elicits a muscle contraction without cooperation from the patient. Therefore, NMES effectiveness on quadriceps thickness was studied. Adult CI patients were included day 2-4 after admission.1 quadriceps muscle was randomly selected (dominant or non-dominant) and received daily 60 minutes NMES,7 consecutive days. Ultrasonography was used to measure thickness of both quadriceps.2 subgroups were compared to identify factors that potentially were related to NMES effect. Patients were classified as responders if change in muscle thickness between the stimulated and non-stimulated leg was equal to or larger than the mean change. Muscle strength was assessed (MRC and handheld dynamometry) in cooperative patients. 47 patients (60±15yr, APACHE II score 26±8) completed the study. The decrease in the stimulated leg was significantly smaller than the control (-6% and -12% respectively, p=0.007). The responders (n=21) showed significantly lower quality of muscle contractions compared to the non-responders (p=0.007). Sepsis tended to be more frequently present in responder group (p=0.069) and APACHE II score was higher (28±9 vs 24±8;p=0.093). Multiple regression analysis showed that patients with poor muscle contraction were 4.7 times more likely to be responder. Effects were more pronounced in patients more prone to loss of muscle mass. No differences in strength measures were found between the stimulated and non-stimulated quadriceps in 18 patients. This study showed that NMES is able to attenuate loss of muscle mass in uncooperative patients with prolonged ICU stay.