Comparative lung function performance of stroke survivors and age-matched and sex-matched controls

Effects of inspiratory muscle training on pulmonary function, diaphragmatic thickness, balance and exercise capacity in people after stroke: a systematic review and meta-analysis

PURPOSE

To examine the effects of inspiratory muscle training (IMT) on pulmonary and diaphragmatic function, exercise capacity, balance and quality of life (QOL), in post-stroke individuals.

METHODS

A literature search was conducted using MEDLINE, CINAHL, EMBASE, PubMed, PEDro, Web of Science and China Biological Medicine databases. Randomized controlled trials (RCTs) with a PEDro score ≥6 focusing on the effects of IMT were included. The GRADE system was used to determine the certainty of evidence for each outcome.

RESULTS

Nine studies (255 participants) were included. IMT significantly increased forced expiratory volume in one second (FEV1) (4 studies, 112 participants, mean difference (MD)=0.18 litre, 95% confidence interval (CI): 0.14-0.23); maximal inspiratory pressure (MIP) (8 studies, 226 participants, MD = 6.37 cm H2O, 95% CI: 1.26-11.49); and diaphragm thickness fraction (DTf) on both sides (MD of affected side vs. unaffected side: 51 vs. 37%). The evidence certainty for diaphragmatic function was moderate. No significant change was observed in forced vital capacity (FVC), balance function, exercise capacity and QOL.

CONCLUSION

This review reveals moderate evidence certainty in support of IMT improving diaphragmatic function. It appears that a training intensity between 30 and 50% MIP results in a significantly improved MIP.

Benefits of inspiratory muscle training therapy in institutionalized adult people with cerebral palsy: A double-blind randomized controlled trial

BACKGROUND

Respiratory health problems are one of the main causes of morbidity and mortality in adult people with cerebral palsy (CP). The influence of respiratory muscle training has not yet been studied in this population group. The objective of the study was to evaluate and compare the efficacy of two protocols with inspiratory muscle training (IMT), low intensity and high intensity, to improve respiratory strength and pulmonary function in adults with CP.

METHODS

The study was a controlled, randomized, double-blind trial with allocation concealment. Twenty-seven institutionalized CP patients were recruited and randomly distributed in the high-intensity training group (HIT) or low-intensity training group (LIT). Over 8 weeks, an IMT protocol was followed 5 days/week, 10 series of 1 min with 1 min rest between them. HIT trained with a load of 40% of the maximum inspiratory pressure (MIP) and LIT with 20%. Respiratory strength and pulmonary function were evaluated.

RESULTS

After IMT intervention, MIP, maximum expiratory pressure, forced expiratory volume in 1 s (FEV1) and peak expiratory flow increased in both groups; in HIT 29%, 19%, 13%, and 8%, respectively (p = 0.000, p = 0.000, p = 0.002, p = 0.001) and in LIT 17%, 7%, 3%, and 4%, respectively (p = 0.000, p = 0.000, p = 0.049, p = 0.113). All the improvements were significantly higher in HIT than in LIT.

CONCLUSION

Inspiratory muscle training improved respiratory muscle strength and pulmonary function in adults with CP. Training with a 40% MIP load improved all the evaluated parameters and was the most effective treatment for adults with CP.

Effects of respiratory muscle training on post-stroke rehabilitation: A systematic review and meta-analysis

BACKGROUND

Stroke often results in significant respiratory dysfunction in patients. Respiratory muscle training (RMT) has been proposed as a rehabilitative intervention to address these challenges, but its effectiveness compared to routine training remains debated. This systematic review and meta-analysis aim to evaluate the effects of RMT on exercise tolerance, muscle strength, and pulmonary function in post-stroke patients.

AIM

To systematically assess the efficacy of RMT in improving exercise tolerance, respiratory muscle strength, and pulmonary function in patients recovering from a stroke, and to evaluate whether RMT offers a significant advantage over routine training modalities in enhancing these critical health outcomes in the post-stroke population.

METHODS

Following the Preferred Reporting Items for Systematic reviews and Meta-Analyses guidelines, a comprehensive search across PubMed, Embase, Web of Science, and the Cochrane Library was conducted on October 19, 2023, without temporal restrictions. Studies were selected based on the predefined inclusion and exclusion criteria focusing on various forms of RMT, control groups, and outcome measures [including forced expiratory volume in the first second (FEV1), forced vital capacity (FVC), maximal voluntary ventilation (MVV), peak expiratory flow (PEF), maximal inspiratory pressure (MIP), maximal expiratory pressure (MEP), and 6-min walking test (6MWT)]. Only randomized controlled trials (RCTs) were included. Data extraction and quality assessment were conducted independently by two reviewers using the Cochrane Collaboration's risk of bias tool. Statistical analyses, including those using the fixed-effect and random-effects models, sensitivity analysis, and publication bias assessment, were performed using Review Manager software.

RESULTS

A total of 15 RCTs were included. Results indicated significant improvements in MIP (12.51 cmH2O increase), MEP (6.24 cmH2O increase), and various pulmonary function parameters (including FEV1, FVC, MVV, and PEF). A substantial increase in 6MWT distance (22.26 meters) was also noted. However, the heterogeneity among studies was variable, and no significant publication bias was detected.

CONCLUSION

RMT significantly enhances walking ability, respiratory muscle strength (MIP and MEP), and key pulmonary function parameters (FEV1, FVC, MVV, and PEF) in post-stroke patients. These findings support the incorporation of RMT into post-stroke rehabilitative protocols.

Efficacy of diaphragmatic breathing exercise on respiratory, cognitive, and motor function outcomes in patients with stroke: a systematic review and meta-analysis

Background

Stroke disrupts the functions carried out by the brain such as the control of movement, sensation, and cognition. Disruption of movement control results in hemiparesis that affects the function of the diaphragm. Impaired function of the diaphragm can in turn affect many outcomes such as respiratory, cognitive, and motor function. The aim of this study is to carry out a systematic review and meta-analysis to determine the efficacy of diaphragmatic breathing exercise on respiratory, cognitive, and motor outcomes after stroke.

Method

The study was registered in PROSPERO (CRD42023422293). PubMED, Embase, Web of Science (WoS), PEDro, Scopus, and CENTRAL databases were searched until September 2023. Only randomized controlled trials comparing diaphragmatic breathing exercise with a control were included. Information on the study authors, time since stroke, mean age, height, weight, sex, and the protocols of the experimental and control interventions including intensity, mean scores on the outcomes such as respiratory, cognitive, and motor functions were extracted. Cochrane risks of bias assessment tool and PEDro scale were used to assess the risks of bias and methodological quality of the studies. Narrative synthesis and meta-analysis were used to summarize the results, which were then presented in tables, risk-of-bias graph, and forest plots. The meta-analysis was carried out on respiratory function [forced vital capacity (FVC), forced expiratory volume in 1 s (FEV1), FEV1/FVC, peak expiratory flow (PEF)] and motor function (trunk impairment, and internal and external oblique muscles activity).

Results

Six studies consisting of 151 participants were included. The results of the meta-analyses showed that diaphragmatic breathing exercise is only superior to the control at improving respiratory function, FVC (MD = 0.90, 95% CI = 0.76 to 1.04, P < 0.00001), FEV1 (MD = 0.32, 95% CI = 0.11 to 0.52, P = 0.002), and PEF (MD = 1.48, 95% CI = 1.15 to 1.81, P < 0.00001).

Conclusion

There is limited evidence suggesting that diaphragmatic breathing exercise may help enhance respiratory function, which may help enhance recovery of function post stroke.

Systematic Review Registration

PROSPERO, identifier CRD42023422293.

Pulmonary Function Tests Post-Stroke. Correlation between Lung Function, Severity of Stroke, and Improvement after Respiratory Muscle Training

Stroke is a significant cause of mortality and chronic morbidity caused by cardiovascular disease. Respiratory muscles can be affected in stroke survivors, leading to stroke complications, such as respiratory infections. Respiratory function can be assessed using pulmonary function tests (PFTs). Data regarding PFTs in stroke survivors are limited. We reviewed the correlation between PFTs and stroke severity or degree of disability. Furthermore, we reviewed the PFT change in stroke patients undergoing a respiratory muscle training program. We searched PubMed until September 2023 using inclusion and exclusion criteria in order to identify studies reporting PFTs post-stroke and their change after a respiratory muscle training program. Outcomes included lung function parameters (FEV1, FVC, PEF, MIP and MEP) were measured in acute or chronic stroke survivors. We identified 22 studies of stroke patients, who had undergone PFTs and 24 randomised controlled trials in stroke patients having PFTs after respiratory muscle training. The number of patients included was limited and studies were characterised by great heterogeneity regarding the studied population and the applied intervention. In general, PFTs were significantly reduced compared to healthy controls and predicted normal values and associated with stroke severity. Furthermore, we found that respiratory muscle training was associated with significant improvement in various PFT parameters and functional stroke parameters. PFTs are associated with stroke severity and are improved after respiratory muscle training.

Respiratory Parameters as Predictors of Balance and Gait Ability in Patients with Stroke at Discharge

Pulmonary complications are frequent in stroke, contributing to both mortality and morbidity rates. Respiratory parameters in such patients encompass both pulmonary function and respiratory muscle strength. Identifying respiratory function variables that influence the balance and gait ability of patients with stroke is crucial for enhancing their recovery in these aspects. However, no study has assessed predictions for a comprehensive array of balance and gait abilities in such patients. We aimed to examine whether initial respiratory muscle strength and pulmonary function can predict balance and gait ability at discharge from a rehabilitation program. Thirty-one patients with stroke were included in this prospective observational study. Multiple regression models with a forward selection procedure were employed to identify respiratory parameters (including peak expiratory flow and maximal expiratory pressure) that contributed to the results of balance assessments and gait evaluations at the time of discharge. The peak expiratory flow (PEF) served as a predictor explaining 42.0% of the variance. Similarly, the maximal expiratory pressure (MEP) was a predictor variable explaining 32.0% of the variance. PEF and MEP assessments at the initial stage as predictive factors for both balance and gait ability are important in stroke management.

Pulmonary function in patients with chronic stroke compared with a control group of healthy people matched by age and sex

BACKGROUND

Effects of chronic stroke on pulmonary function are largely unknown.

AIM

To compare lung volumes in people with chronic stroke with a control group of healthy people matched by age and sex, as well as to investigate the relationship between the lung volumes and functional capacity.

METHODS

A cross-sectional study involving people with chronic stroke. Cases were matched to a control group of healthy people. Lung function and the distance walked during the Six-Minute Walk Test (6MWD) were the main outcomes. Independent t-tests were used to compare pulmonary function between groups and the Pearson correlation coefficient was used to assess any relationship between lung volumes and the 6MWD in the stroke group.

RESULTS

Sixty-six participants (24 males in each group; 56.5 ± 15.5 years) were included. People with stroke presented significantly lower lung volumes when compared to the control group. The median of forced vital capacity (FVC) was 79% and peak expiratory flow was 64% of the reference value. The 6MWD was found to be weakly correlated with inspiratory reserve volume (r = 0.39, p = .03) and peak inspiratory flow (r = 0.35, p = .05).

CONCLUSIONS

People with chronic stroke show decreased lung volumes when compared with healthy people and this likely impacts on their functional capacity.

Breathing Exercises for Improving Cognitive Function in Patients with Stroke

Patients with stroke may experience a certain degree of cognitive decline during the period of recovery, and a considerable number of such patients have been reported to show permanent cognitive damage. Therefore, the period of recovery and rehabilitation following stroke is critical for rapid cognitive functional improvements. As dysfunctional breathing has been reported as one of the factors affecting the quality of life post stroke, a number of studies have focused on the need for improving the breathing function in these patients. Numerous breathing exercises have been reported to enhance the respiratory, pulmonary, cognitive, and psychological functions. However, scientific evidence on the underlying mechanisms by which these exercises improve cognitive function is scattered at best. Therefore, it has been difficult to establish a protocol of breathing exercises for patients with stroke. In this review, we summarize the psychological, vascular, sleep-related, and biochemical factors influencing cognition in patients and highlight the need for breathing exercises based on existing studies. Breathing exercises are expected to contribute to improvements in cognitive function in stroke based on a diverse array of supporting evidence. With relevant follow-up studies, a protocol of breathing exercises can be developed for improving the cognitive function in patients with stroke.

Association of Pulmonary Function With Motor Function Trajectories and Disability Progression Among Older Adults: A Long-Term Community-Based Cohort Study

BACKGROUND

The association of pulmonary function (PF) with motor function and disability remains unclear. We investigate the association of PF with motor function trajectories and disability progression, and explore the role of social activity, cognitive function, and cardiovascular diseases (CVDs) in this relationship.

METHODS

Within the Rush Memory and Aging Project, 1 403 disability-free participants (mean age: 79.28 years) were followed for up to 22 years. PF was measured with a composite score based on peak expiratory flow, forced expiratory volume in 1 second, and forced vital capacity at baseline. Global motor function including dexterity, gait, and hand strength was assessed annually using 10 motor tests. Disability was evaluated according to the basic activities of daily living. Social activity was defined as the frequency of common types of social interaction. Global cognitive function was assessed using a battery of 19 cognitive performance tests. CVDs (including stroke, congestive heart failure, and heart diseases) were ascertained at baseline. Linear mixed-effects models were used.

RESULTS

Compared to high PF, low PF was related to faster decline in global motor function (β = -0.005, 95% confidence interval [CI]: -0.008 to -0.001) and all 3 specific motor abilities (p < .05), as well as faster progression of disability (β = 0.012, 95% CI: 0.009 to 0.014). There was a statistically significant interaction between PF and social activity/cognitive function on disability progression (β = 0.005, 95% CI: 0.001 to 0.009, p = .010/β = 0.004, 95% CI: 0.001 to 0.009, p = .025).

CONCLUSION

Poor PF accelerates motor function decline and the progression of disability. A high level of social activity and cognitive function appear to decelerate disability progression related to poor PF.

Feasibility of a standardized protocol for respiratory training with intermitted positive pressure breathing ventilator application in dysphonia and dysarthria

BACKGROUND

Brain damage can affect several functions related to speech production leading to dysphonia and dysarthria. Most rehabilitation treatments focus on articulation training rather than on pneumophonic coordination and respiratory muscle strength. Respiratory training using an intermitted positive pressure breathing (IPPB) ventilator can be used for this last purpose; no agreement on a standard protocol has been reached to date.

AIM

To evaluate the feasibility and the effectiveness of a standardized incremental protocol of respiratory training using IPPB to treat dysphonia and dysarthria.

DESIGN

Case series study.

SETTING

Neuropsychological Rehabilitation Unit in an Italian Neurorehabilitation Division.

POPULATION

Thirty-two subjects with dysphonia and dysarthria resulting from neurological lesion.

METHODS

Participants were assessed using clinical evaluation scales (GIRBAS scale of dysphonia, Robertson dysarthria profile), respiratory function test, and arterial blood gas analysis in air. The evaluations were performed at baseline and after 20 sessions of respiratory training with IPPB. The protocol provided a default increment of ventilator parameters. All subjects also underwent a standard speech and language therapy treatment. A satisfaction survey to assess acceptability and the Goal Attainment Scale were applied.

RESULTS

All participants fulfilled the protocol. No complications or discomfort were reported. Subjects' satisfaction at survey was 97.7%. After respiratory training, all respiratory function parameters increased, but only maximal voluntary ventilation (MVV), maximum inspiratory pressure (MIP), and maximum expiratory pressure (MEP) were statistically significant (P<0.05). Clinical evaluation scales significantly improved (P<0.05). Correlation between respiratory function parameters and clinical evaluation scales showed a moderate correlation between MVV, MEP, MIP, and Robertson dysarthria profile (P<0.01). A weak correlation was found between MIP, MVV, and GIRBAS scale (P<0.05).

CONCLUSIONS

Our protocol showed to be practical and well-tolerated. After respiratory training, MVV, MIP and MEP improved in significantly. Clinical scale scores improved in all participants.

CLINICAL REHABILITATION IMPACT

Respiratory training using IPPB ventilator can be useful in implementing speech and language treatments in subjects with dysphonia and dysarthria linked to brain injury.

Asthma and stroke: a narrative review

Asthma is a heterogeneous disease, usually characterized by chronic airway inflammation, bronchial reversible obstruction and hyperresponsiveness to direct or indirect stimuli. It is a severe disease causing approximately half a million deaths every year and thus possessing a significant public health burden. Stroke is the second leading cause of death and a major cause of disability worldwide. Asthma and asthma medications may be a risk factors for developing stroke. Nevertheless, since asthma is associated with a variety of comorbidities, such as cardiovascular, metabolic and respiratory, the increased incidence of stroke in asthma patients may be due to a confounding effect. The purpose of this review is to analyze the complex relationship between asthma and stroke.

Recovery process of respiratory muscle strength in patients following stroke: A Pilot Study

OBJECTIVE

To determine the recovery process of respiratory muscle strength during 3 months following stroke, and to investigate the association of change in respiratory muscle strength and physical functions. Additionally, we compared respiratory muscle strength with those of healthy subjects.

METHOD

In this prospective, observational study, 19 stroke patients and 19 healthy subjects were enrolled. Maximal inspiratory pressure (MIP), maximal expiratory pressure (MEP), motricity index, trunk control test, 6-minute walk test (6MWT) and functional independence measure were assessed at 1, 2, and 3 months from stroke onset in stroke patients. MIP and MEP were assessed at arbitrary times in healthy subjects. Repeated one-way analysis of variance with Bonferroni post-hoc test was used to compare the change in respiratory muscle strength in each period in stroke patients. Pearson's correlation coefficient was computed for changes in respiratory muscle strength and physical functions. Student's t-test was used to compare respiratory muscle strength between stroke patients at 3 months from onset and healthy subjects.

RESULTS

MIP was significantly increased at 3 months compared to 1 month. MEP was significantly increased in 2 months and 3 months, compared to 1 month. MIP changes associated with 6MWT changes. Compared to healthy subjects, MIP and MEP at 3 months were significantly lower in stroke patients.

CONCLUSION

Respiratory muscle strength significantly increased during 3 months following stroke. However, the trend of recovery may be different. MIP changes may associated with walking endurance changes. During 3 months following stroke, respiratory muscle strength did not recover to healthy subjects.

Effects of Inspiratory Muscle Training on Respiratory Muscle Strength, Trunk Control, Balance and Functional Capacity in Stroke Patients: A single-blinded randomized controlled study

Objective: Aim of the study was to examine the effects of inspiratory muscle training (IMT) on respiratory function, respiratory muscle strength, trunk control, balance, and functional capacity in stroke patients.Methods: 21 stroke individuals were randomly divided into two groups as control group and treatment group. Respiratory function test, Maximal Inspiratory Pressure (MIP) and Maximal Expiratory Pressure (MEP) were evaluated. Also, Trunk Impairment Scale (TIS), Timed Up and Go Test (TUG) Berg Balance Scale (BBS), and Six-Minute Walk Test (6MWT) were performed. Neurodevelopmental treatment program was performed in both groups for 5 days a week for 6 weeks, and IMT was given to the treatment group. IMT was started from 40% of MIP.Results: After treatment, respiratory functions, respiratory muscle strength, and trunk control and balance improved in the treatment group. In the control group; however, only the balance level was improved. When the changes in the evaluation parameters between the groups were compared, there were only statistically significant differences in the TIS, Peak Expiratory Flow (PEF) and MIP in the treatment group (p˂0.05), the change amounts in other evaluation parameters were similar (p˃0.05). When the effect size of the groups was compared, the effect size of the variables in the treatment group was found to be higher.Conclusions: As a conclusion, IMT, which was given in addition to the neurological physiotherapy and rehabilitation program to our patients, improved inspiratory muscle strength and trunk control. We believe that this result will raise awareness for physiotherapists working in the field of neurological rehabilitation about including respiratory muscle training in the rehabilitation program of stroke patients.

[Pulmonary insufficiency in acute stroke: risk factors and mechanisms of development]

Various degrees of pulmonary insufficiency (PI) (PaO₂ ≤60 mm Hg, SaO₂ ≤90%) are diagnosed in most of patients with severe acute stroke (AS). Frequency and severity of PI positively correlates with the severity of AS. PI worsens patient's condition, prolongs the hospitalization period, and increases the probability of fatal outcome. Early clinical signs of PI may be undiagnosed due to the severity of stroke and thus not treated. The initiating pathogenic mechanism of PI is stress-related activation of sympathetic nervous system (SNS) and systemic immunosuppression. In severe stroke with mass effect, the rapid and significant increase in intracranial pressure may additionally activate the SNS. Risk factors of PI include older age, previous pulmonary disease, prolonged supine position, respiratory muscle dysfunction, apnea, and concomitant somatic diseases. Decompensation of somatic diseases leads to multiple stage reactions with facilitation of functional and morphologic changes in the pulmonary system, hypoxemia and hypoxia, promotes infectious complications and multiple organ failure and worsens neurological outcome. Diagnosis and treatment of PI in AS decreases mortality and improves rehabilitation prognosis.

Effects of Inspiratory Muscles Training Plus Rib Cage Mobilization on Chest Expansion, Inspiratory Accessory Muscles Activity and Pulmonary Function in Stroke Patients

After stroke, limited ribcage movement may lead to impaired respiratory function. Combining threshold inspiratory muscle training with rib cage joint mobilization has been shown to enhance the recovery of respiratory function in patients with stroke. The present study investigated whether the combination of rib cage joint mobilization and inspiratory muscle training would improve chest expansion, inspiratory muscle activity, and pulmonary function after stroke. Thirty stroke patients were recruited and randomly assigned to one of the two groups, namely 6-week rib cage joint mobilization with inspiratory muscle training (experimental group) or inspiratory muscle training alone (control group). Outcome measures included upper and lower chest expansion, activity of accessory inspiratory muscles (latissimus dorsi (LD) and upper trapezius (UT)), and pulmonary function (forced vital capacity (FVC), forced expiratory volume in 1 s (FEV1), and peak expiratory flow (PEF)). All evaluations were conducted at baseline and after 6 weeks of inspiratory muscle training. Significant increases were observed in upper and lower chest expansion, LD and UT muscle activity, FVC, FEV1, and PEF in both the groups. Upper and lower chest expansion and muscle activity of UT and LD were significantly higher in the experimental group than in the control group. No significant differences were observed in FVC, FEV1, and PEF between the groups. Inspiratory muscle training is effective in improving chest expansion, inspiratory muscle activity, and pulmonary function after stroke. The addition of rib cage joint mobilization further increases chest expansion and inspiratory muscle activity.

Implementation of a gait center training to improve walking ability and vital parameters in inpatient neurological rehabilitation- a cohort study

BACKGROUND

Many studies showed that robot-assisted gait training might improve walking of patients after stroke. The question remains whether patients with other neurological diagnoses can improve their ability to walk by training in a gait center. Aim of the present study was therefore to investigate the effects of a gait center training in inpatient neurological rehabilitation on walking ability.

METHODS

We implemented a gait center training in addition to individual inpatient rehabilitation. Our primary outcome was walking ability based on the Functional Ambulation Categories (FAC). Our secondary outcomes were vital capacity and blood pressure. We predefined subgroups of patients with ischemic and hemorrhagic stroke and critical illness myopathy (CIM) and polyneuropathy (CIP).

RESULTS

We included 780 patients from our inpatient rehabilitation center in our cohort study. We analyzed 329 patients with ischemic, 131 patients with hemorrhagic stroke and 74 patients with CIP/ CIM. A large number of patients were able to improve their ability to walk. At the end of rehabilitation, patients with ischemic stroke and FAC 3 = increased theirFAC scores by 5%, FAC 4 = 4% and FAC 5 = 7%. Patients with hemorrhagic stroke and FAC 3 = increased by 5%, FAC 4 = 11% and FAC 5 = 9% and patients with CIP/CIM increased by FAC 3 = 3%, FAC 4 = 22% and FAC 5 = 26%. The largest improvement in walking ability during rehabilitation had patients with a FAC = 1 at baseline who improved by a median of 1.4 FAC points (p < 0.001). After adjusting for the number of gait training sessions, the largest improvement in walking ability during rehabilitation had patients with a FAC = 0 at baseline who improved by 1.8 FAC points (p < 0.001).

CONCLUSIONS

Implementation of an additional gait center training may significantly improve walking ability in neurological rehabilitation.

Evaluation of Respiratory Muscular Strength Compared to Predicted Values in Patients with Stroke

The purpose of this study was to evaluate the inspiratory and expiratory muscle strength of individuals affected by stroke and to compare it with the predicted values in the literature considering their corresponding age. Respiratory muscle strength was evaluated in 22 elderly people who had sequels of stroke, four with right hemiparesis, 16 with left hemiparesis and two with bilateral, of ages ranging from 34 to 82 years. The collected data were submitted to statistical analysis using a Mann–Whitney test to evaluate if there was a significant difference in the average data collected when compared with a mean of the predicted data in the literature. Fourteen men and eight women were evaluated, who obtained mean values of 71.85 cmH₂O and 57.75 cmH₂O, respectively, for a maximal inspiratory pressure (MIP), and when compared to the predicted values for men and women, 105.41 cmH₂O (p-value 0.0019) and 80.57 cmH₂O (p-value 0.00464) were significantly lower. For a maximal expiratory pressure (MEP), the mean value obtained for men was 62.28 cmH₂O and 49.5 cmH₂O for women, whereas the predicted values in the literature were 114.79 cmH₂O (p-value < 0.0001) and 78, 46 cmH₂O (p-value 0.0059), respectively. In the statistical analysis, it was possible to notice that the studied population did not reach the predicted age indexes and that there was a significant difference between the median columns. In conclusion, there is a weakness in the respiratory muscles of hemiparetic men and women due to stroke.

Respiratory repercussions of neurological diseases and how best to manage them

Introduction: The high incidence of respiratory impairments in patients with neurological diseases is recognized, but the design, dosage, and effectiveness of interventions to manage them are seen as an ongoing challenge.Areas covered: This article summarizes the evidence regarding the respiratory impairments in major neurological diseases, and how to best manage them.Expert opinion: On the balance of available evidence, respiratory impairments are part of the clinical profile of neurological diseases including Multiple Sclerosis, Stroke, and Parkinson's Disease, acquiring more importance as the pathologies progress. It is recognized that knowledge gaps remain in some areas of relevance related to respiratory function and further research is required. When considering the therapeutic options, the respiratory training emerges as the approach with most evidence. However, important questions remain unsolved: what kind, how much, and how to best include respiratory interventions is uncertain. At present, respiratory programs also fail to include clinically relevant factors such as ambulation and trunk stability.

Feasibility and trend of pulmonary function in a pilot trial of aerobic walking exercise in non-ambulatory stroke survivors

Background: Lung function is compromised in stroke survivors, which may cause fatigue and exercise intolerance. Furthermore, past studies of aerobic exercise have involved only stroke survivors who could walk independently. Stroke survivors who were unable to walk were not included in the previous research-investigating changes in lung function from walking exercise interventions. In this pilot study, the feasibility and the effect of aerobic walking exercise on lung function was examined in non-ambulatory stroke survivors using a treadmill, bodyweight support system, and a gait training device.Methods: This study was a single group trial. Eight non-ambulatory stroke survivors (five males, mean age 63.3 ± 13.7 years, seven with ischemic stroke) completed a low intensity walking exercise program (30 min/session; three sessions/week for 8 weeks) and lung function test. Before and after the intervention, vital capacity (VC) and forced vital capacity (FVC) using a spirometer were measured according to the guideline from American Thoracic Society/European Respiratory Society.Results: The rates of compliance and attrition were 100% and 10%; respectively, and no adverse events were reported. There were significant differences between pre- and post-intervention assessments in FVC (p = .09), percentage of predicted VC (p = .08), and percentage of predicted FVC (p = .08).Conclusions: In non-ambulatory stroke survivors, aerobic walking exercise is feasible and safe. Also, the results are promising and suggest that aerobic walking exercise may improve lung function; more data are needed.

Immediate effects of the respiratory stimulation on ventilation parameters in ischemic stroke survivors: A randomized interventional study (CONSORT)

BACKGROUND

Post-stroke brain damage, which affects the central control of respiration, leads to various respiratory disorders. They can be caused by the weakening of the respiratory muscles and chest movements, which can indirectly contribute to an impairment of the ventilation function. The aim of the study is an objective assessment of the effect of a single-session intervention of respiratory stimulation through Proprioceptive Neuromuscular Facilitation (PNF) on chosen respiratory parameters and the following comparison of these changes with a group in which positioning was used (intra- and intergroup comparison).

METHODS

This was a randomized interventional study evaluating the respiratory parameters depending on the applied respiratory stimulation in patients after ischemic stroke. The patients qualified to participate in the study were randomly assigned to 1 of 2 groups: PNF-treated group - in which respiratory stimulation through PNF was used, PNF untreated group - in which positioning was used. The research procedure consisted of several stages. First, an interview was conducted with each participant and basic data was collected. Then, spirometry was conducted, after which each patient underwent a single-session intervention according to their assigned group. Finally, the patients were given another spirometry examination. The main outcomes will be to compare the results of a spirometry test (FVC, FEV1, FEV1/ FVC%, PEF) before and after single-session intervention and between groups.

RESULTS

Based on the inclusion and exclusion criteria for the study, 60 patients took part in the measurement. The values of FEV1/FVC% were higher in PNF-treated group than in PNF-untreated group, if the post-intervention measures (P = .04) are considered. The difference between the pre- and post-intervention results of the FEV1/FVC% values in PNF-untreated group was substantially lower than in PNF-treated group (P = .001).

CONCLUSION

A single application of respiratory stimulation through PNF positively affect air flow in the respiratory tract. Application of PNF stimulation contributed to an increase in the FEV1/FVC% parameter. However, no positive changes were noted in the other parameters, which would provide proof of the beneficial effect of facilitation on the respiratory system function.

Chest wall volume and asynchrony in stroke and Parkinson's disease subjects: A case-control study

Background

The expansion of the rib cage and abdomen occurs in a synchronic way during a coordinated contraction of the diaphragm and the abdominal and intercostal muscles under normal conditions and healthy. The presence of restrictive respiratory disease may lead to uncoordinated action of the respiratory muscles which affects breathing pattern and chest wall volumes. The aim of this study was to evaluate chest wall volumes, chest wall asynchrony and inspiratory paradoxical movement of breathing, as well as the influence of the time of disease diagnosis in subjects with Parkinson’s disease and post-Stroke in comparison to healthy individuals.

Methods

Total and compartmental chest wall volumes, chest wall asynchrony and paradoxical movement were measured at rest in a seated position by Optoelectronic Plethysmography in 76 individuals (29 healthy individuals, 20 post-Stroke and 27 Parkinson’s disease subjects). Post-stroke and Parkinson’s disease subjects were also grouped according to the length of diagnosis.

Results

In both groups with restrictive respiratory disease we observed that pulmonary rib cage compartment (V_RCp) volume is reduced when compared to healthy subjects (p <0.05). This same pattern was observed when analyzing post-stroke subjects with more than three years of diagnosis and Parkinson’s subjects with less than three years of diagnosis (p<0.05). Furthermore, post-stroke subjects with inspiratory paradoxical movement showed decreased total and compartmental chest wall volumes (p<0.05), while individuals with Parkinson’s disease with inspiratory paradoxical movement only presented a decrease in pulmonary rib cage compartment volume (p<0.05).

Conclusion

Our study presents new findings for better understanding of chest wall volumes and chest wall asynchrony in post-stroke and Parkinson’s disease individuals. Half of the subjects with post-Stroke and Parkinson’s disease presented inspiratory paradox movement, but changes in breathing pattern was especially observed in post-stroke subjects with more than three years of diagnosis.

Proprioceptive Neuromuscular Facilitation for Accessory Respiratory Muscles Training in Patients After Ischemic Stroke

This study focused on how pulmonary function is affected by proprioceptive neuromuscular facilitation (PNF) of accessory respiratory muscles in the chronic post-stroke phase. The study involved patients who had had ischemic stroke 6 months or more before the PNF treatment investigated. The objective was to define the effect of PNF on bioelectrical resting and maximum activity of the accessory muscles. Patients were randomly assigned to PNF treatment and just positioning treatment as a reference for comparison; 30 patients each. Electromyography of accessory muscles was investigated before and after physiotherapeutic treatments. We found that there was a greater reduction in EMG activity in all muscles investigated after PNF compared to positioning treatment alone. A reduction of muscle activity due to PNF concerned both affected and unaffected body side, but it was greater on the affected side. We conclude that a reduction of the accessory respiratory muscle activity due to PNF treatment could be of benefit in chronic stoke patients in that it would help normalize breathing pattern and thereby prevent the development of hypoxia.

Chronic Obstructive Pulmonary Disease and Stroke

Chronic obstructive pulmonary disease (COPD) is currently the fourth leading cause of death in the world and its incidence and prevalence is on the rise. It is evident that COPD is linked to cardiovascular disease. In the last years, several studies demonstrated that COPD may also be a risk factor for stroke, another major cause of death worldwide. Taking in consideration that COPD has multiple comorbidities it is hard to say whether COPD is an independent risk factor for stroke or it is due to confounding effect. This review is aimed to discuss current data on COPD and stroke, potential links, therapy, and prevention. Current data suggest that COPD may increase the risk of hemorrhagic stroke. The incidence of other stroke subtypes may also be increased in COPD or may be due to confounding effect. However, COPD patients who have stroke are at risk for pulmonary and extrapulmonary complications. We conclude that more studies are needed to further clarify the links between COPD and stroke. The management of COPD as well as the use of prevention therapy is essential to decrease the risk for stroke and should be at special attention in pulmonary medicine and neurology.

Cerebral desaturation in heart failure: Potential prognostic value and physiologic basis

Cerebral tissue oxygen saturation (SctO₂) reflects cerebral perfusion and tissue oxygen consumption, which decline in some patients with heart failure with reduced ejection fraction (HFrEF) or stroke, especially during exercise. Its physiologic basis and clinical significance remain unclear. We aimed to investigate the association of SctO₂ with oxygen transport physiology and known prognostic factors during both rest and exercise in patients with HFrEF or stroke. Thirty-four HFrEF patients, 26 stroke patients, and 17 healthy controls performed an incremental cardiopulmonary exercise test using a bicycle ergometer. Integrated near-infrared spectroscopy and automatic gas analysis were used to measure cerebral tissue oxygenation and cardiac and ventilatory parameters. We found that SctO₂ (rest; peak) were significantly lower in the HFrEF (66.3±13.3%; 63.4±13.8%,) than in the stroke (72.1±4.2%; 72.7±4.5%) and control (73.1±2.8%; 72±3.2%) groups. In the HFrEF group, SctO₂ at rest (SctO_2rest) and peak SctO₂ (SctO_2peak) were linearly correlated with brain natriuretic peptide (BNP), peak oxygen consumption (V˙O2peak), and oxygen uptake efficiency slope (r between -0.561 and 0.677, p < 0.001). Stepwise linear regression showed that SctO_2rest was determined by partial pressure of end-tidal carbon dioxide at rest (P_ETCO_2rest), hemoglobin, and mean arterial pressure at rest (MAP_rest) (adjusted R = 0.681, p < 0.05), while SctO_2peak was mainly affected by peak carbon dioxide production (V˙CO2peak) (adjusted R = 0.653, p < 0.05) in patients with HFrEF. In conclusion, the study delineates the relationship of cerebral saturation and parameters associated with oxygen delivery. Moreover, SctO_2peak and SctO_2rest are correlated with some well-recognized prognostic factors in HFrEF, suggesting its potential prognostic value.

Neuropulmonology

Neuropulmonology refers to the complex interconnection between the central nervous system and the respiratory system. Neurologic injury includes traumatic brain injury, hemorrhage, stroke, and seizures, and in each there are far-reaching effects that can result in pulmonary dysfunction. Systemic changes can induce impairment of pulmonary function due to changes in the core structure and function of the lung. The conditions and disorders that often occur in these patients include aspiration pneumonia, neurogenic pulmonary edema, and acute respiratory distress syndrome, but also several abnormal respiratory patterns and sleep-disordered breathing. Lung infections, pulmonary edema - neurogenic or cardiogenic - and pulmonary embolus all are a serious barrier to recovery and can have significant effects on outcomes such as hospital course, prognosis, and mortality. This review presents the spectrum of pulmonary abnormalities seen in neurocritical care.

Hypoxia after stroke: a review of experimental and clinical evidence

Background

Hypoxia is a common occurrence following stroke and associated with poor clinical and functional outcomes. Normal oxygen physiology is a finely controlled mechanism from the oxygenation of haemoglobin in the pulmonary capillaries to its dissociation and delivery in the tissues. In no organ is this process more important than the brain, which has a number of vascular adaptions to be able to cope with a certain threshold of hypoxia, beyond which further disruption of oxygen delivery potentially leads to devastating consequences. Hypoxia following stroke is common and is often attributed to pneumonia, aspiration and respiratory muscle dysfunction, with sleep apnoea syndromes, pulmonary embolism and cardiac failure being less common but important treatable causes. As well as treating the underlying cause, oxygen therapy is a vital element to correcting hypoxia, but excessive use can itself cause molecular and clinical harm. As cerebral vascular occlusion completely obliterates oxygen delivery to its target tissue, the use of supplemental oxygen, even when not hypoxic, would seem a reasonable solution to try and correct this deficit, but to date randomised clinical trials have not shown benefit.

Conclusion

Whilst evidence for the use of supplemental oxygen therapy is currently lacking, it is vital to rapidly identify and treat all causes of hypoxia in the acute stroke patient, as a failure to will lead to poorer clinical outcomes. The full results of a large randomised trial looking at the use of supplemental oxygen therapy are currently pending.

The correlation of respiratory muscle strength and cough capacity in stroke patients

[Purpose] The purpose of this study was to investigate the correlation between respiratory muscle strength and cough capacity in stroke patients. [Subjects and Methods] Forty-two stroke patients were assigned to 2 different groups (intervention group=21, control group=21). Both groups participated in a conventional stroke rehabilitation program, with the intervention group also receiving respiratory muscle training for 20 to 30 minutes a day, 3 times a week for 8 weeks. Respiratory muscle strength (maximal inspiratory pressure, maximal expiratory pressure), forced vital capacity, and cough capacity were measured. [Results] The intervention group showed significant increases in maximal inspiratory pressure, maximal expiratory pressure, forced vital capacity, and cough capacity. The change in maximal inspiratory pressure, maximal expiratory pressure, and forced vital capacity showed a significant correlation with cough capacity, with maximal expiratory pressure showing the highest correlation. [Conclusion] The present study showed that the increase in maximal expiratory pressure plays an important role in improving the cough capacity of stroke patients.

Effects of Respiratory Muscle Training on Respiratory Function, Respiratory Muscle Strength, and Exercise Tolerance in Patients Poststroke: A Systematic Review With Meta-Analysis

OBJECTIVE

To examine the effects of respiratory muscle training on respiratory function, respiratory muscle strength, and exercise tolerance in patients poststroke.

DATA SOURCES

We searched MEDLINE, Cochrane Library, Embase, SciELO, Physiotherapy Evidence Database (PEDro), and CINAHL (from the earliest date available to November 2015) for trials.

STUDY SELECTION

Randomized controlled trials (RCTs) that examined the effects of respiratory muscle training versus nonrespiratory muscle training in patients poststroke. Two reviewers selected studies independently.

DATA EXTRACTION

Extracted data from the published RCTs. Study quality was evaluated using the PEDro Scale. Weighted mean differences (WMDs), standard mean differences (SMDs), and 95% confidence intervals (CIs) were calculated.

DATA SYNTHESIS

Eight studies met the study criteria. Respiratory muscle training improved maximal inspiratory pressure WMDs (7.5; 95% CI, 2.7-12.4), forced vital capacity SMDs (2.0; 95% CI, 0.6-3.4), forced expiratory volume at 1 second SMDs (1.2; 95% CI, 0.6-1.9), and exercise tolerance SMDs (0.7; 95% CI, 0.2-1.2). No serious adverse events were reported.

CONCLUSIONS

Respiratory muscle training should be considered an effective method of improving respiratory function, inspiratory muscle strength, and exercise tolerance in patients poststroke. Further research is needed to determine optimum dosages and duration of effect.

Chronic obstructive pulmonary disease and cerebrovascular disease: A comprehensive review

Along with the aging population, the public health burden of cerebrovascular disease is increasing. Cerebral small vessel disease and accumulation of brain pathology associate with cognitive decline and can lead to clinical outcomes, such as stroke and dementia. Chronic Obstructive Pulmonary Disease (COPD) is a common respiratory disease among elderly. The quality of life and prognosis of patients with COPD is greatly determined by the presence of comorbidities including stroke and cognitive impairment. Despite the clinical relevance of cerebral small vessel disease, stroke and (vascular) cognitive impairment in patients with COPD, literature is scarce and underlying mechanisms are unknown. The aim of the present review is therefore to summarize current scientific knowledge, to provide a better understanding of the interplay between COPD and the aging brain and to define remaining knowledge gaps. This narrative review article 1) overviews the epidemiology of cerebral small vessel disease, stroke and cognitive impairment in patients with COPD; 2) discusses potential underlying mechanisms including aging, smoking, systemic inflammation, vasculopathy, hypoxia and genetic susceptibility; and 3) highlights areas requiring further research.

Peripheral to central: Organ interactions in stroke pathophysiology

Stroke is associated with a high risk of disability and mortality, and with the exception of recombinant tissue-type plasminogen activator for acute stroke, most treatments have proven ineffective. Clinical translation of promising experimental therapeutics is limited by inadequate stroke models and a lack of understanding of the mechanisms underlying acute stroke and how they affect outcome. Bidirectional communication between the ischemic brain and peripheral immune system modulates stroke progression and tissue repair, while epidemiological studies have provided evidence of an association between organ dysfunction and stroke risk. This crosstalk can determine the fate of stroke patients and must be taken into consideration when investigating the pathophysiological mechanisms and therapeutic options for stroke. This review summarizes the current evidence for interactions between the brain and other organs in stroke pathophysiology in basic and clinic studies, and discusses the role of these interactions in the progression and outcome of stroke and how they can direct the development of more effective treatment strategies.

Direct assessment of lung function in COPD using CT densitometric measures

To investigate whether lung function in patients with chronic obstructive pulmonary disease (COPD) can be directly predicted using CT densitometric measures and assess the underlying prediction errors as compared with the traditional spirometry-based measures. A total of 600 CT examinations were collected from a COPD study. In addition to the entire lung volume, the extent of emphysema depicted in each CT examination was quantified using density mask analysis (densitometry). The partial least square regression was used for constructing the prediction model, where a repeated random split-sample validation was employed. For each split, we randomly selected 400 CT exams for training (regression) purpose and the remaining 200 exams for assessing performance in prediction of lung function (e.g., FEV1 and FEV1/FVC) and disease severity. The absolute and percentage errors as well as their standard deviations were computed. The averaged percentage errors in prediction of FEV1, FEV1/FVC%, TLC, RV/TLC% and DLco% predicted were 33%, 17%, 9%, 18% and 23%, respectively. When classifying the exams in terms of disease severity grades using the CT measures, 37% of the subjects were correctly classified with no error and 83% of the exams were either correctly classified or classified into immediate neighboring categories. The linear weighted kappa and quadratic weighted kappa were 0.54 (moderate agreement) and 0.72 (substantial agreement), respectively. Despite the existence of certain prediction errors in quantitative assessment of lung function, the CT densitometric measures could be used to relatively reliably classify disease severity grade of COPD patients in terms of GOLD.

Lung vital capacity and oxygen saturation in adults with cerebral palsy

BACKGROUND

Individuals with infantile cerebral palsy have multiple disabilities. The most conspicuous syndrome being investigated from many aspects is motor movement disorder with a spastic gait pattern. The lung function of adults with spasticity attracts less attention in the literature. This is surprising because decreased thoracic mobility and longstanding scoliosis should have an impact on lung function. With increasing age and the level of disability, individuals become susceptible to lung infections and reflux illness, and these are accompanied by increased aspiration risk. This study examined, with different methods, to what extent adults with congenital cerebral palsy and acquired spastic paresis - following traumatic brain injury - showed restriction of lung function. It also assessed the contribution of disability level on this restriction.

METHODS

The oxygen saturation of 46 adults with a diagnosis of cerebral palsy was measured with an oximeter. Lung vital capacity was measured with a mobile spirometer and excursion of the thorax was clinically registered. The gross motor function levels and the presence or absence of scoliosis were determined.

RESULTS

A significantly positive correlation between lung vital capacity and chest expansion was established. Both the lung vital capacity and the thorax excursion decreased with increases in gross motor function level. Oxygen saturation remained within the normal range in all persons, in spite of reduced values of the measured lung parameters. No statistically significant dependency between lung vital capacity and oxygen saturation, and between chest expansion and oxygen saturation was found. The scoliotic deformities of the spine were associated with an additional decrease in the vital capacity, but this did not affect blood oxygen supply.

CONCLUSION

Despite the decreased chest expansion and the significantly reduced lung volume in adults with cerebral palsy, sufficient oxygen supply was registered.