Respiratory muscle training for cervical spinal cord injury

A three-arm randomized controlled trial of aerobic and resistance training in women with spinal cord injuries: Effects on physical fitness and pulmonary function

Background

This study aimed to investigate the effects of different volumes of aerobic training (AT) and resistance training (RT) during a concurrent exercise training program on selected indicators of physical fitness and pulmonary function in women with spinal cord injury (SCI).

Methods

Twenty-three inactive females with complete or incomplete SCI from T6 to L5 were divided into three groups: concurrent training with a focus on AT (CTAT; two weekly sessions of AT and one of RT), concurrent training with a focus on RT (CTRT; two weekly sessions of RT and one of AT), and control (CON). Tests were performed before and after an 8-week experimental period for indicators of pulmonary function, aerobic power, endurance performance, muscular strength and endurance, speed, and change of direction.

Results

Markers of both aerobic and muscular fitness increased in the CTAT and CTRT groups, but not in CON. There were significant differences in aerobic power and endurance performance between the CTAT and CTRT groups, with greater changes in CTAT. Both CTAT and CTRT improved respiratory functions, with no differences between them (p > 0.05).

Conclusions

CTAT and CTRT improved most of the indicators of physical fitness. However, CTAT should be used to achieve higher aerobic power and endurance without compromising muscle strength.

The effect of craniocervical flexion and neck endurance exercises plus pulmonary rehabilitation on pulmonary function in spinal cord injury: a pilot single-blinded randomised controlled trial

STUDY DESIGN

Randomised controlled trial with computerised allocation, assessor blinding and intention-to-treat analysis.

OBJECTIVE

This study wanted to prove that cervicocranial flexion exercise (CCFE) and superficial neck flexor endurance training combined with common pulmonary rehabilitation is feasible for improving spinal cord injury people's pulmonary function.

SETTING

Taoyuan General Hospital, Ministry of Health and Welfare: Department of Physiotherapy, Taiwan.

METHOD

Thirteen individuals who had sustained spinal cord injury for less than a year were recruited and randomised assigned into two groups. The experimental group was assigned CCFEs and neck flexor endurance training plus normal cardiopulmonary rehabilitation. The control group was assigned general neck stretching exercises plus cardiopulmonary rehabilitation. Lung function parameters such as forced vital capacity (FVC), forced expiratory volume in 1 s (FEV1), FEV1/FVC, peak expiratory flow rate (PEFR), inspiratory capacity (IC), dyspnoea, pain, and neck stiffness were recorded once a week as short-term outcome measure.

RESULT

The experimental group showed significant time effects for FVC (pre-therapy: 80.4 ± 21.4, post-therapy: 86.9 ± 16.9, p = 0.021, 95% CI: 0.00-0.26) and PEFR (pre-therapy: 67.0 ± 33.4; post-therapy: 78.4 ± 26.9, p = 0.042, 95% CI: 0.00-0.22) after the therapy course. Furthermore, the experimental group showed significant time effects for BDI (experimental group: 6.3 ± 3.0; control group: 10.8 ± 1.6, p = 0.012, 95% CI: 0.00-0.21).

CONCLUSION

The exercise regime for the experimental group could efficiently increase lung function due to the following three reasons: first, respiratory accessory muscle endurance increases through training. Second, posture becomes less kyphosis resulting increasing lung volume. Third, the ratio between superficial and deep neck flexor is more synchronised.

IRB TRIAL REGISTRATION

TYGH108045.

CLINICAL TRIAL REGISTRATION

NCT04500223.

Noninvasive respiratory assistance as aid for respiratory care in neuromuscular disorders

Chronic respiratory failure is a common complication of neuromuscular disease. The use of noninvasive ventilation and mechanically assisted cough can reduce symptoms of hypoventilation, slow lung function decline, improve sleep quality, and in some cases prolong survival in patients with neuromuscular disease. In this article, we review indications for the initiation of noninvasive ventilation and mechanically assisted cough as well as provide recommendations for settings and titration. We discuss the evidence supporting the use of noninvasive ventilation as an adjunct to rehabilitation in patients with neuromuscular disease. Lastly, we review the ethical considerations that are relevant to decisions regarding initiation and cessation of noninvasive ventilation. While noninvasive ventilation and mechanically assisted cough have become standards of care in many forms of neuromuscular disease, most current recommendations are based on expert opinion rather than much-needed data from prospective clinical trials and we emphasize topics requiring future research.

A preliminary study on the feasibility of community game-based respiratory muscle training for individuals with high cervical spinal cord injury levels: a novel approach

Background

Respiratory disorders result in rehospitalization and premature death of patients with cervical spinal cord injuries (CSCI). Community game-based respiratory muscle training (RMT) programs could reduce secondary complications.

Methods

We examined the feasibility and preliminary efficacy of RMT as a community-based exercise program. Among the 10 included participants (eight male and two female), four, one, one, and four reported C3, C4, C5, and C6 complete injuries, respectively (eight graded by American Spinal Injury Association impairment scale [ASIA] A and two by ASIA B). Their mean age was 43 ± 12.3 y. The time since injury was 10 ± 6.7 y. The participants completed an RMT program for 60 min/day, twice weekly, for 8 weeks. The participants were trained in the use of a newly developed game-based RMT device. The device provides consistent pressure for respiratory muscle strength and endurance training. Seven RMT devices were modified to allow 10 game-based RMT programs. Forced vital capacity (FVC), forced expiratory volume in 1 s (FEV₁), peak expiratory flow (PEF), vital capacity (VC), inspiratory capacity (IC), inspiratory reserve volume (IRV), expiratory reserve volume (ERV), maximum inspiratory pressure (MIP), maximum expiratory pressure (MEP), and peak cough flow (PCF) were measured.

Results

There were improvements after RMT compared to pre-RMT in FVC (p = 0.027, 10.62%, 0.22 effect size [ES]), PEF (p = 0.006, 23.21%, 0.45 ES), VC (p = 0.002, 35.52%, 0.60 ES), IC (p = 0.001, 46.94%, 0.81 ES), IRV (p = 0.001, 90.53%, 1.22 ES), MIP (p = 0.002, 97.25%, 1.32 ES), MEP (p = 0.005, 141.12%, 1.07 ES), and PCF (p = 0.001, 35.60%, 0.74 ES). The participants reported a positive impact of the program.

Conclusions

Community game-based RMT for individuals with CSCI appears to be safe and feasible. Community exercise with RMT use may have a positive impact on the respiratory measures for patients with CSCI who are vulnerable to respiratory compromise.

Trial registration

KCT0005980.

Translation and validation into Portuguese of the international spinal cord injury pulmonary function basic data set

INTRODUCTION

Spinal cord injury (SCI) is a serious disabling syndrome, and the clinical picture depends on the level and extent of the injury. The International Spinal Cord Society (ISCoS) and the American Spinal Cord Association (ASIA) have developed instruments (Data Sets) to assess the various aspects of the SCI. In 2012, the International SCI Pulmonary Function Basic Data Set was elaborated. It is composed of four questions and spirometry for the collection of lung function basic data.

OBJECTIVE

The objective was to translate and validate the International SCI Pulmonary Function Basic Data Set to the Portuguese language.

METHODS

The entire methodology followed the recommendations of the ISCoS and ASIA. Two translations of the original version into Portuguese were performed, and after consensus among the translators, the Portuguese version was sent for back-translation. After back-translation and comparison with the original version, the final Portuguese version was obtained. For the second phase of the study, 30 SCI individuals were selected. Two interviewers applied the questionnaire in two distinct moments.

RESULTS

All results presented constant, excellent, or perfectly concordant data, except for the third question in the inter-rater comparison, where the Kappa coefficient showed value reasonable in the first interview and good in the second.

CONCLUSION

The translation into Brazilian Portuguese of the "International SCI Pulmonary Function Basic Data Set" created a valid and highly reliable instrument, like the original without linguistic and cultural disagreements that allow its use in the evaluation of patients with SCI in Brazil.

Adherence to and impact of home-based high-intensity IMT in people with spinal cord injury: a pilot study

Study design

The pilot study was completed in 5 phases (Control and 4 phases of IMT) incorporating assessments at Baseline 1 (BL1), BL2, Follow-up 1 (F1), F2, F3, and F4.

Objective

To assess the adherence and impact of a daily high-intensity (80% of max) inspiratory muscle training (IMT) home program with once weekly supervision for people with spinal cord injury (SCI).

Setting

Assessments: research institution or zoom. IMT: participant’s home.

Methods

Participants completed daily IMT in IMT Phase 1 and 2, once weekly in IMT Phase 3, self-selected frequency in IMT Phase 4. All phases had one weekly supervised session except IMT Phase 4. Primary outcomes included adherence and a difficulty score [DS (0- not difficult to 10- the most difficult)]. Secondary outcomes included respiratory function and seated balance.

Results

Data from 10 people with chronic SCI (>1 year) (Cervical level of injury: 6, AIS: A-B, injury duration: 10.9 years 95% CI [3.9, 18.1]) were used in the analysis. Participants completed 69% of their training days in IMT Phase 1 and 65% overall reporting an average DS of 7.4 ± 1.4. Only one participant completed training during IMT Phase 4. One participant’s training load was reduced due to suspected overtraining. Maximal inspiratory pressure (MIP), sustained MIP (SMIP), and total power (TP), improved significantly (p < 0.05) from BL2 to F1.

Conclusion

Our data suggest that people with SCI can perform high-intensity IMT at home to improve inspiratory performance. It is strongly recommended that participants be intermittently monitored for adherence and safety.

ClinicalTrials.gov Registration number: NCT04210063.

Effect of Vocal Exercise on Respiratory Function and Voice Quality in Patients with Cervical Spinal Cord Injury: A Mini-review

Objectives

This study reviewed the effect of vocal exercise on patients with cervical spinal cord injury (SCI).

Methods

An electronic search of the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, and Embase databases was conducted for relevant studies published between 1980 and 2022. The review included studies that used randomized controlled trials to examine the effects of vocal exercise on people with cervical SCI.

Results

We screened 1351 articles, of which 4 studies were eligible for inclusion. Vocal exercises were conducted two or three times a week for 12-24 weeks. Random sequences were adequately generated in all studies. All studies used respiratory function as the main outcome, and three studies used vocal quality as an outcome. In all studies, there were no dropouts other than those caused by unexpected illness. Vocal exercises were reported to have a positive effect on respiratory function in all studies and on voice quality in three studies. Meta-analysis was not possible because of the heterogeneity of the studies.

Conclusions

Vocal exercise for SCI is a sustainable method that does not require special equipment or skills. More studies with large sample sizes are needed to confirm the effects of vocal exercises in patients with cervical SCI.

The effects of inspiratory muscle training on inspiratory muscle strength, lung function and quality of life in adults with spinal cord injuries: a systematic review and Meta-analysis

PURPOSE

This systematic review and meta-analysis aimed to evaluate the effectiveness of inspiratory muscle training (IMT) on respiratory muscle strength, lung function and quality of life (QOL) in adults with spinal cord injuries (SCI).

METHODS

Databases were searched up to June 2022; CENTRAL, CINAHL, MEDLINE, PEDRo, and PubMed. Following PRISMA reporting guidelines, two independent reviewers selected studies and extracted data. Study quality and levels of evidence were assessed.

RESULTS

Following selection from 624 initial search results, six randomised controlled trials were identified, comprising 124 participants. Quality of Evidence was very low to moderate. Meta-analysis showed that post intervention, IMT significantly improved maximal inspiratory pressure (MD 15.72 cmH2O, 95% CI 5.02, 26.41, p = 0.004) when compared with a control intervention. There was no significant benefit for physical QOL (SMD 0.12, 95% CI -1.01, 1.25, p = 0.84), mental QOL (SMD -0.2, 95% CI -1.72, 1.33, p = 0.80), maximal expiratory pressure (MD 5.19 cmH2O, 95% CI -4.16, 14.55, p = 0.80), or FEV1 (MD 0.26 L, 95% CI -0.19, 0.7, p = 0.26). Sensitivity analyses found larger effects for studies with 8 week interventions (MD 17.5 cmH2O (95% CI 3.36 to 31.66)) and spring loaded devices alone (MD 21.18 cmH2O, 95% CI 9.65 to 32.72).

CONCLUSION

Moderate quality evidence suggests IMT improves respiratory strength in adults with an SCI. The mental and physical QOL outcomes provided very low quality of evidence, with considerable heterogeneity between study results, leading to inconsistency. Further research is warranted to investigate medium and long-term impact of robust IMT protocols, accounting for patient motivation and adherence to IMT.IMPLICATIONS FOR REHABILITATIONInspiratory muscle training (IMT) significantly improves respiratory muscle strength in adults with spinal cord injuries-irrespective of time since injury, or degree of injury completeness.IMT is a feasible, safe, and worthwhile intervention to implement with adults with spinal cord injuries and can be utilized in a variety of settings.IMT interventions that are 8 weeks long and utilize a spring-loaded inspiratory threshold device may generate the largest improvements in respiratory strength.

Is there a role of pulmonary rehabilitation in extrapulmonary diseases frequently encountered in the practice of physical medicine and rehabilitation?

There is a group of diseases such as low back pain, osteoporosis, fibromyalgia and obesity for which pulmonary rehabilitation can be applied. Although these diseases do not directly impact the lungs, respiratory dysfunction occurs through various mechanisms during the disease process and complicates the underlying primary disease. Respiratory dysfunction and spirometric abnormalities have been observed from the early stages of these diseases, even without obvious signs and symptoms. These patients should be carefully evaluated for pulmonary problems as a sedentary lifestyle may hide the presence of respiratory symptoms. Once pulmonary problems have been detected, pulmonary rehabilitation should be added to the routine treatment of the primary disease.

Optogenetic activation of the diaphragm

Impaired diaphragm activation is common in many neuromuscular diseases. We hypothesized that expressing photoreceptors in diaphragm myofibers would enable light stimulation to evoke functional diaphragm activity, similar to endogenous bursts. In a mouse model, adeno-associated virus (AAV) encoding channelrhodopsin-2 (AAV9-CAG-ChR2-mVenus, 6.12 × 10¹¹ vg dose) was delivered to the diaphragm using a minimally invasive method of microinjection to the intrapleural space. At 8-18 weeks following AAV injection, mice were anesthetized and studied during spontaneous breathing. We first showed that diaphragm electromyographic (EMG) potentials could be evoked with brief presentations of light, using a 473 nm high intensity LED. Evoked potential amplitude increased with intensity or duration of the light pulse. We next showed that in a paralyzed diaphragm, trains of light pulses evoked diaphragm EMG activity which resembled endogenous bursting, and this was sufficient to generate respiratory airflow. Light-evoked diaphragm EMG bursts showed no diminution after up to one hour of stimulation. Histological evaluation confirmed transgene expression in diaphragm myofibers. We conclude that intrapleural delivery of AAV9 can drive expression of ChR2 in the diaphragm and subsequent photostimulation can evoke graded compound diaphragm EMG activity similar to endogenous inspiratory bursting.

Reduced Muscle Activity of the Upper Extremity in Individuals with Spinal Cord Injuries

Compromised physical ability due to musculoskeletal impairment among spinal cord injury (SCI) patients is known to negatively affect their quality of life. It is essential to comprehensively understand the muscle strength of the upper extremity among patients with SCI to enhance muscle function and capacity to engage in an active lifestyle. The objective of this study was to evaluate the muscle strength of 15 upper extremity muscles among patients with SCI and compare the relative weakness of individual muscles to the control group. Seven male patients with SCI with ASIA impairment scale D and E and 33 males in the control group participated in this study. Each participant performed maximal voluntary contraction of individual muscles, and the electromyography data were recorded. The results showed that the majority of the upper extremity muscles (12 out of 15) showed considerable weakness (24 to 53%) relative to the control group. Furthermore, the relative strength (ranking) of individual muscles among 15 upper extremity muscles was different between patients with SCI and the control group. This information would be useful to the selective strengthening of specific muscles as an intensive rehabilitation effort and prevent overuse and adverse injuries due to excessive muscle training.

Noninvasive and invasive mechanical ventilation for neurologic disorders

Patients with acute neurologic injuries frequently require mechanical ventilation due to diminished airway protective reflexes, cardiopulmonary failure secondary to neurologic insults, or to facilitate gas exchange to precise targets. Mechanical ventilation enables tight control of oxygenation and carbon dioxide levels, enabling clinicians to modulate cerebral hemodynamics and intracranial pressure with the goal of minimizing secondary brain injury. In patients with acute spinal cord injuries, neuromuscular conditions, or diseases of the peripheral nerve, mechanical ventilation enables respiratory support under conditions of impending or established respiratory failure. Noninvasive ventilatory approaches may be carefully considered for certain disease conditions, including myasthenia gravis and amyotrophic lateral sclerosis, but may be inappropriate in patients with Guillain-Barré syndrome or when relevant contra-indications exist. With regard to discontinuing mechanical ventilation, considerable uncertainty persists about the best approach to wean patients, how to identify patients ready for extubation, and when to consider primary tracheostomy. Recent consensus guidelines highlight these and other knowledge gaps that are the focus of active research efforts. This chapter outlines important general principles to consider when initiating, titrating, and discontinuing mechanical ventilation in patients with acute neurologic injuries. Important disease-specific considerations are also reviewed where appropriate.

Systematic Review of Incidence Studies of Pneumonia in Persons with Spinal Cord Injury

Pneumonia continues to complicate the course of spinal cord injury (SCI). Currently, clinicians and policy-makers are faced with only limited numbers of pneumonia incidence in the literature. A systematic review of the literature was undertaken to provide an objective synthesis of the evidence about the incidence of pneumonia in persons with SCI. Incidence was calculated per 100 person-days, and meta-regression was used to evaluate the influence of the clinical setting, the level of injury, the use of mechanical ventilation, the presence of tracheostomy, and dysphagia. For the meta-regression we included 19 studies. The incidence ranged from 0.03 to 7.21 patients with pneumonia per 100 days. The main finding of this review is that we found large heterogeneity in the reporting of the incidence, and we therefore should be cautious with interpreting the results. In the multivariable meta-regression, the incidence rate ratios showed very wide confidence intervals, which does not allow a clear conclusion concerning the risk of pneumonia in the different stages after a SCI. Large longitudinal studies with a standardized reporting on risk factors, pneumonia, and detailed time under observation are needed. Nevertheless, this review showed that pneumonia is still a clinically relevant complication and pneumonia prevention should focus on the ICU setting and patients with complete tetraplegia.

Inspiratory Muscle Performance and Anthropometric Measures-Novel Assessments Related to Pulmonary Function in People with Spinal Cord Injury: A Pilot Study

OBJECTIVE

To investigate the feasibility and validity of using the novel axillary:umbilical (A:U) ratio and sustained maximal inspiratory pressure (SMIP) as supplementary measures in the assessment of respiratory function in people with spinal cord injury.

DESIGN

Pilot study with a single day of data collection. All measurements were taken with participants in their personal wheelchairs to best represent normal functioning and positioning for each individual.

SETTING

Research institution.

PARTICIPANTS

A convenience sample of 30 community dwelling volunteers with chronic spinal cord injury (C2-T12, American Spinal Injury Association Impairment Scale A-D) participated.

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

Participants underwent anthropometric measurements (trunk height, abdominal circumference, axillary circumference) and assessment of inspiratory muscle performance, incluidng maximal inspiratory pressure, SMIP, and inspiratory duration, as well as standard pulmonary function tests.

RESULTS

The A:U ratio and SMIP were recorded for all participants. The SMIP was significantly related to more respiratory performance measures than the maximal inspiratory pressure (P<.05) and the A:U ratio was significantly related to more respiratory performance measures than any other anthropometric measure (P<.05). Additionally, an A:U ratio cutoff point detected individuals with a peak expiratory flow ≥ 80% of their predicted value with a sensitivity and specificity of 85.7% and 91.3%, respectively (area under the curve: 0.92).

CONCLUSIONS

It is feasible to capture the A:U Ratio and SMIP in individuals with spinal cord injury. Further, the strong significant relationships of SMIP and the A:U ratio to respiratory performance measures suggests their clinical importance in the pulmonary assessment and risk stratification of people with chronic spinal cord injury.

Respiratory Training and Plasticity After Cervical Spinal Cord Injury

While spinal cord injuries (SCIs) result in a vast array of functional deficits, many of which are life threatening, the majority of SCIs are anatomically incomplete. Spared neural pathways contribute to functional and anatomical neuroplasticity that can occur spontaneously, or can be harnessed using rehabilitative, electrophysiological, or pharmacological strategies. With a focus on respiratory networks that are affected by cervical level SCI, the present review summarizes how non-invasive respiratory treatments can be used to harness this neuroplastic potential and enhance long-term recovery. Specific attention is given to "respiratory training" strategies currently used clinically (e.g., strength training) and those being developed through pre-clinical and early clinical testing [e.g., intermittent chemical stimulation via altering inhaled oxygen (hypoxia) or carbon dioxide stimulation]. Consideration is also given to the effect of training on non-respiratory (e.g., locomotor) networks. This review highlights advances in this area of pre-clinical and translational research, with insight into future directions for enhancing plasticity and improving functional outcomes after SCI.

Community exercise for individuals with spinal cord injury with inspiratory muscle training: A pilot study

Context/Objective: Respiratory disorders are a common cause of rehospitalization, and premature death in individuals with spinal cord injuries (SCI). Respiratory training combined with community exercise programs may be a method to reduce secondary complications in this population.Objective: The present study explores the inclusion of inspiratory muscle training (IMT) in an existing community exercise program.Design: Case series.Setting: Community.Participants: Participants (N = 6) completed the exercise program. Five were male and one was female; four reported incomplete injuries, and two reported complete injuries; four had cervical injuries, and two had thoracic injuries. The average age was 33 years (SD = 18.6) and time since injury was 7 years (SD = 4.0).Interventions: Participants completed an 8-week program, once-per-week for 4 h that included a circuit of resistance training, aerobic exercise, trunk stability, and education. IMT was completed as a home exercise program.Outcome Measures: Transfer test, T-shirt test, four-directional reach, four-directional trunk strength, weekly training diaries, and a subjective interview.Results: Twenty-eight training logs were collected. All measures improved: transfer test (mean = -14.62, SD = 7.00 s), T-shirt test (mean = -7.83, SD = 13.88 s), four-directional reach (mean = 3.75, SD = 8.06 in) and hand-held dynamometer (mean = 6.73, SD = 8.02 kg). Individuals reported a positive impact of the program.Conclusions: This pilot study demonstrated community exercise with IMT use may have positive impact on functional measures for people with SCI who are vulnerable to respiratory compromise. Continued education may increase successful health outcomes.Trial Registration: NCT03743077.

A Nomogram for Predicting Acute Respiratory Failure After Cervical Traumatic Spinal Cord Injury Based on Admission Clinical Findings

OBJECTIVES

Acute respiratory failure (ARF) is a common medical complication in patients with cervical traumatic spinal cord injury (TSCI). To identify independent predictors for ARF onset in patients who underwent cervical TSCI without premorbid respiratory diseases and to apply appropriate medical supports based on accurate prediction, a nomogram relating admission clinical information was developed for predicting ARF during acute care period.

METHODS

We retrospectively reviewed clinical profiles of patients who suffered cervical TSCI and were emergently admitted to Qingdao Municipal Hospital from 2014 to 2020 as the training cohort. Univariate analysis was performed using admission clinical variables to estimate associated factors and a nomogram for predicting ARF occurrence was generated based on the independent predictors from multivariate logistic regression analysis. This nomogram was assessed by concordance index for discrimination and calibration curve with internal-validated bootstrap strategy. Receiver operating characteristic curve was conducted to compare the predictive accuracy between the nomogram and the traditional gold standard, which combines neuroimaging and neurological measurements by using area under the receiver operating characteristic curve (AUC). An additional 56-patient cohort from another medical center was retrospectively reviewed as the test cohort for external validation of the nomogram.

RESULTS

162 patients were eligible for this study and were included in the training cohort, among which 25 individuals developed ARF and were recorded to endure more complications. Despite the aggressive treatments and prolonged intensive care unit cares, 14 patients insulted with ARF died. Injury level, American Spinal Injury Association Impairment Scale (AIS) grade, admission hemoglobin (Hb), platelet to lymphocyte ratio, and neutrophil percentage to albumin ratio (NPAR) were independently associated with ARF onset. The concordance index of the nomogram incorporating these predictors was 0.933 in the training cohort and 0.955 in the test cohort, although both calibrations were good. The AUC of the nomogram was equal to concordance index, which presented better predictive accuracy compared with previous measurements using neuroimaging and AIS grade (AUC 0.933 versus 0.821, Delong's test p < 0.001). Similar significant results were also found in the test cohort (AUC 0.955 versus 0.765, Delong's test p = 0.034). In addition, this nomogram was translated to a Web-based calculator that could generate individual probability for ARF in a visualized form.

CONCLUSIONS

The nomogram incorporating the injury level, AIS grade, admission Hb, platelet to lymphocyte ratio, and NPAR is a promising model to predict ARF in patients with cervical TSCI who are absent from previous respiratory dysfunction. This nomogram can be offered to clinicians to stratify patients, strengthen evidence-based decision-making, and apply appropriate individualized treatment in the field of acute clinical care.

Development and pilot testing of novel game-based respiratory rehabilitation exercise devices for patients with tetraplegia

BACKGROUND:

Individuals with spinal cord injuries (SCI) show restricted breathing patterns with reduced lung volumes and capacities.

OBJECTIVE:

To improve breathing in such individuals, we aimed to develop breathing exercise devices using a user-centered design (UCD) and then assess the effects of these devices on breathing.

METHODS:

Patients with SCI were involved in the device development. Preliminary online survey participants were recruited from the community, and interview and pilot test participants were recruited from a patient self-help group. The four UCD phases were repeatedly performed. Users required fun, easy, multi-player, and safe exercise devices.

RESULTS:

Seven breathing exercise devices were developed, and 10 different game-based exercises were performed. Two individuals participated in a pilot test involving a respiratory rehabilitation exercise program conducted twice weekly for 60 min/session over 8 weeks. Lung function was assessed using a spirometer. Forced vital capacity, forced expiratory volume in 1 s, and vital capacity showed minimal changes, whereas maximum inspiratory and expiratory pressures improved. Participants reported that the exercises were entertaining and that the competitive nature of the game-like exercises encouraged further participation.

CONCLUSION:

Breathing exercise programs using our developed devices can improve breathing and positively affect the psychological states and sociability of users.

Exoskeleton-assisted walking improves pulmonary function and walking parameters among individuals with spinal cord injury: a randomized controlled pilot study

BACKGROUND

Exoskeleton-assisted walking (EAW) is expected to improve the gait of spinal cord injury (SCI) individuals. However, few studies reported the changes of pulmonary function (PF) parameters after EAW trainings. Hence, we aimed to explore the effect of EAW on PF parameters, 6-min walk test (6MWT) and lower extremity motor score (LEMS) in individuals with SCI and to compare those with conventional trainings.

METHODS

In this prospective, single-center, single-blinded randomized controlled pilot study, 18 SCI participants were randomized into the EAW group (n = 9) and conventional group (n = 9) and received 16 sessions of 50-60 min training (4 days/week, 4 weeks). Pulmonary function parameters consisting of the forced vital capacity (FVC), forced expiratory volume in 1 s (FEV₁), forced expiratory flow (FEF), peak expiratory flow, and maximal voluntary ventilation, 6MWT with assisted devices and LEMS were reported pre- and post-training.

RESULTS

Values of FVC (p = 0.041), predicted FVC% (p = 0.012) and FEV₁ (p = 0.013) were significantly greater in EAW group (FVC: 3.8 ± 1.1 L; FVC% _pred = 94.1 ± 24.5%; FEV₁: 3.5 ± 1.0 L) compared with conventional group (FVC: 2.8 ± 0.8 L; FVC% _pred = 65.4 ± 17.6%; FEV₁: 2.4 ± 0.6 L) after training. Participants in EAW group completed 6MWT with median 17.3 m while wearing the exoskeleton. There was no difference in LEMS and no adverse event.

CONCLUSIONS

The current results suggest that EAW has potential benefits to facilitate PF parameters among individuals with lower thoracic neurological level of SCI compared with conventional trainings. Additionally, robotic exoskeleton helped walking.

TRIAL REGISTRATION

Registered on 22 May 2020 at Chinese Clinical Trial Registry (ChiCTR2000033166). http://www.chictr.org.cn/edit.aspx?pid=53920&htm=4 .

Effects of Respiratory Muscle Training on Baroreflex Sensitivity, Respiratory Function, and Serum Oxidative Stress in Acute Cervical Spinal Cord Injury

Background: respiratory complications are a leading cause of morbidity and mortality in individuals with spinal cord injury (SCI). We examined the effects of respiratory muscle training (RMT) in patients with acute cervical SCI. Methods: this prospective trial enrolled 44 adults with acute cervical SCI, of which twenty received RMT and twenty-four did not receive RMT. Respiratory function, cardiovascular autonomic function, and reactive oxidative species (ROS) were compared. The experimental group received 40-min high-intensity home-based RMT 7 days per week for 10 weeks. The control group received a sham intervention for a similar period. The primary outcomes were the effects of RMT on pulmonary and cardiovascular autonomic function, and ROS production in individuals with acute cervical SCI. Results: significant differences between the two groups in cardiovascular autonomic function and the heart rate response to deep breathing (p = 0.017) were found at the 6-month follow-up. After RMT, the maximal inspiratory pressure (p = 0.042) and thiobarbituric acid-reactive substances (TBARS) (p = 0.006) improved significantly, while there was no significant difference in the maximal expiratory pressure. Significant differences between the two groups in tidal volume (p = 0.005) and the rapid shallow breathing index (p = 0.031) were found at 6 months. Notably, the SF-36 (both the physical (PCS) and mental (MCS) component summaries) in the RMT group had decreased significantly at the 6-month follow-up, whereas the clinical scores did not differ significantly (p = 0.333) after RMT therapy. Conclusions: High-intensity home-based RMT can improve pulmonary function and endurance and reduce breathing difficulties in patients with respiratory muscle weakness after injury. It is recommended for rehabilitation after spinal cord injury.

Correlation and Predicted Equations of MIP/MEP from the Pulmonary Function, Demographics and Anthropometrics in Healthy Thai Participants aged 19 to 50 Years

Objective:

To identify the correlations and possible predicted equations of maximal inspiratory (MIP) and expiratory mouth pressure (MEP) values from pulmonary function test (PFT), demographics, and anthropometrics.

Methods:

This study involved 217 healthy participants (91 males and 126 females) aged 19 to 50 years. The PFT (forced vital capacity; FVC, forced expiratory volume in 1 second; FEV1, maximal mid-expiratory flow; MMEF, and peak expiratory flow; PEF) was performed by spirometry, whereas MIP and MEP were evaluated by a respiratory pressure meter. Pearson correlation and multiple linear regression, with the stepwise method, were used for statistical analysis.

Results:

The MIP and MEP had a significant positive correlation with weight, height, body mass index (BMI), and waist circumference. MIP had a significant positive correlation with FVC (%) and PEF (L/s and %), as well as a negative correlation with FEV1/FVC (ratio and %) and MMEF (%). Whereas, MEP showed a significant positive correlation with PEF (L/s and %) and negative correlation with FEV1/FVC (ratio and %) and MMEF (L/s). Finally, the predicted MIP and MEP equations were 103.988−97.70 × FEV1/FVC + 31.292 × Sex (male = 1 and female = 0) + 0.662 × PEF (%) and 47.384 + 3.603 × PEF (L/s)−9.514 × MMEF(L/s) + 30.458 × Sex (male = 1 and female = 0) + 0.534 × PEF (%), respectively.

Conclusion:

The respiratory muscle strengths can be predicted from the pulmonary function test, and gender data.

Effects of glossopharyngeal insufflation on pulmonary function in cervical cord injury patients

STUDY DESIGN

Quasi experimental.

OBJECTIVE

To evaluate the effect of glossopharyngeal insufflation on pulmonary function in cervical cord injury.

SETTING

Indian Spinal Injuries Centre, Vasant Kunj, Delhi, India.

METHODS

Thirty-one cervical cord injured (ISNCSCI A and B) subjects received respiratory rehabilitation for 4 weeks, with the experimental group performing glossopharyngeal insufflation along with respiratory rehabilitation. The groups were assessed at baseline and after 4 weeks for pulmonary function test, chest expansion, dyspnea, and chest tightness.

RESULTS

Significant differences were observed in IVC, IC, FVC, FEV1, MEF 75%, PEF, tidal volume, chest expansion, dyspnea, and chest tightness (p < 0.05).

CONCLUSION

Glossopharyngeal insufflation is a technique that can be used to improve the respiratory function after cervical cord injury.

Minimal Clinically Important Differences for Measures of Pain, Lung Function, Fatigue, and Functionality in Spinal Cord Injury

OBJECTIVE

The objective of this study was to determine the minimal clinically important differences (MCIDs) for the numerical pain rating scale (NPRS), peak cough flow (PCF), peak expiratory flow (PEF), fatigue severity scale (FSS), and London chest activities of daily living scale (LCADL) in patients with spinal cord injuries (SCIs) after rehabilitation.

METHODS

Inpatients with SCI from 2 rehabilitation centers participating in a daily rehabilitation program were recruited. The NPRS, PCF, PEF, FSS, and LCADL were collected at baseline and discharge. The global rating of change scale was performed at discharge. MCIDs were calculated using anchor (linear regression, mean change, and receiver operating characteristic curves) and distribution-based methods (0.5 times the baseline SD, standard error of measurement, 1.96 times standard error of measurement, and minimal detectable change) and pooled using arithmetic weighted mean.

RESULTS

Sixty inpatients with SCI (36 males; 54.5 [15.9] years) participated. On average their rehabilitation program lasted 7.3 (1.7) weeks. Pooled MCID estimates were 1.6 points for the NPRS, 69.8 L/min for the PCF, 77.4 L/min for the PEF, 1.1 points for the FSS, and 1.4 points for the LCADL.

CONCLUSION

Established MCIDs for NPRS, PCF, PEF, FSS, and LCADL will help health professionals to interpret results and guide rehabilitation interventions in patients with SCI.

IMPACT

Health professionals and researchers may now use -1.6 points for the NPRS, 69.8 L/min for the PCF, 77.4 L/min for the PEF, 1.1 points for the FSS, and 1.4 points for the LCADL to interpret if changes in pain, cough intensity, expiratory flow, fatigue and activities of daily living after rehabilitation of patients with SCI have been clinically relevant.

Respiratory function and respiratory complications in spinal cord injury: protocol for a prospective, multicentre cohort study in high-income countries

INTRODUCTION

Pneumonia is one of the leading complications and causes of death after a spinal cord injury (SCI). After a cervical or thoracic lesion, impairment of the respiratory muscles decreases respiratory function, which increases the risk of respiratory complications. Pneumonia substantially reduces patient's quality of life, may prolong inpatient rehabilitation time, increase healthcare costs or at worse, lead to early death. Respiratory function and coughing can be improved through various interventions after SCI, but the available evidence as to which aspect of respiratory care should be optimised is inconclusive. Furthermore, ability of respiratory function parameters to predict pneumonia risk is insufficiently established. This paper details the protocol for a large-scale, multicentre research project that aims to evaluate the ability of parameters of respiratory function to predict and understand variation in inpatient risk of pneumonia in SCI.

METHODS AND ANALYSIS

RESCOM, a prospective cohort study, began recruitment in October 2016 across 10 SCI rehabilitation centres from Australia, Austria, Germany, the Netherlands and Switzerland. Inpatients with acute SCI, with complete or incomplete cervical or thoracic lesions, 18 years or older and not/no more dependent on 24-hour mechanical ventilation within the first 3 months after injury are eligible for inclusion. The target sample size is 500 participants. The primary outcome is an occurrence of pneumonia; secondary outcomes include pneumonia-related mortality and quality of life. We will use the longitudinal data for prognostic models on inpatient pneumonia risk factors.

ETHICS AND DISSEMINATION

The study has been reviewed and approved by all local ethics committees of all participating centres. Study results will be disseminated to the scientific community through peer-reviewed journals and conference presentations, to the SCI community, other stakeholders and via social media, newsletters and engagement activities.

TRIAL REGISTRATION DETAILS

ClinicalTrials.gov NCT02891096.

A Primary Care Provider's Guide to Managing Respiratory Health in Subacute and Chronic Spinal Cord Injury

Respiratory complications following spinal cord injury (SCI) have remained the leading cause of death across the lifespan and are one of the most common reasons for hospitalization. Complications from altered respiratory physiology after SCI include atelectasis, pneumonia, venous thromboembolic disease, and sleep-disordered breathing. The risk for complications is greater with higher SCI levels and severity, and mortality from pneumonia is heightened compared to the general population. Optimal primary care for individuals with SCI includes appropriate surveillance for SCI-specific respiratory disease, key preventive care including promotion of influenza immunization and respiratory muscle training, and early identification and treatment of pneumonia with institution of aggressive secretion management strategies. The respiratory physiology and specific management of respiratory complications after SCI is reviewed.

Maximal expiratory pressure is associated with reinstitution of mechanical ventilation after successful unassisted breathing trials in tracheostomized patients with prolonged mechanical ventilation

Objective

Reinstitution of mechanical ventilation (MV) for tracheostomized patients after successful weaning may occur as the care setting changes from critical care to general care. We aimed to investigate the occurrence, consequence and associated factors of MV reinstitution.

Methods

We analyzed the clinical data and physiological measurements of tracheostomized patients with prolonged MV discharged from the weaning unit to general wards after successful weaning to compare between those with and without in-hospital MV reinstitution within 60 days.

Results

Of 454 patients successfully weaned, 116 (25.6%) reinstituted MV at general wards within 60 days; at hospital discharge, 42 (36.2%) of them were eventually liberated from MV, 51 (44.0%) remained MV dependent, and 33 (28.4%) died. Of the 338 patients without reinstitution within 60 days, only 3 (0.9%) were later reinstituted with MV before discharge (on day 67, 89 and 136 at general wards, respectively), and 322 (95.2%) were successfully weaned again at discharge, while 13 (3.8%) died. Patients with MV reinstitution had a significantly lower level of maximal expiratory pressure (P_Emax) before unassisted breathing trial compared to those without reinstitution. Multivariable Cox regression analysis showed fever at RCC discharge (hazard ratio [HR] 14.00, 95% confidence interval [CI] 3.2–61.9) chronic obstructive pulmonary disease (HR 2.37, 95% CI 1.34–4.18), renal replacement therapy at the ICU (HR 2.29, 95% CI 1.50–3.49) and extubation failure before tracheostomy (HR 1.76, 95% CI 1.18–2.63) were associated with increased risks of reinstitution, while P_Emax > 30 cmH₂O (HR 0.51, 95% CI 0.35–0.76) was associated with a decreased risk of reinstitution.

Conclusions

The reinstitution of MV at the general ward is significant, with poor outcomes. The P_Emax measured before unassisted breathing trial was significantly associated with the risk of reinstituting MV at the general wards.

Impact of respiratory muscle training on respiratory muscle strength, respiratory function and quality of life in individuals with tetraplegia: a randomised clinical trial

BACKGROUND

Respiratory complications remain a leading cause of morbidity and mortality in people with acute and chronic tetraplegia. Respiratory muscle weakness following spinal cord injury-induced tetraplegia impairs lung function and the ability to cough. In particular, inspiratory muscle strength has been identified as the best predictor of the likelihood of developing pneumonia in individuals with tetraplegia. We hypothesised that 6 weeks of progressive respiratory muscle training (RMT) increases respiratory muscle strength with improvements in lung function, quality of life and respiratory health.

METHODS

Sixty-two adults with tetraplegia participated in a double-blind randomised controlled trial. Active or sham RMT was performed twice daily for 6 weeks. Inspiratory muscle strength, measured as maximal inspiratory pressure (PImax) was the primary outcome. Secondary outcomes included lung function, quality of life and respiratory health. Between-group comparisons were obtained with linear models adjusting for baseline values of the outcomes.

RESULTS

After 6 weeks, there was a greater improvement in PImax in the active group than in the sham group (mean difference 11.5 cmH2O (95% CI 5.6 to 17.4), p<0.001) and respiratory symptoms were reduced (St George Respiratory Questionnaire mean difference 10.3 points (0.01-20.65), p=0.046). Significant improvements were observed in quality of life (EuroQol-Five Dimensional Visual Analogue Scale 14.9 points (1.9-27.9), p=0.023) and perceived breathlessness (Borg score 0.64 (0.11-1.17), p=0.021). There were no significant improvements in other measures of respiratory function (p=0.126-0.979).

CONCLUSIONS

Progressive RMT increases inspiratory muscle strength in people with tetraplegia, by a magnitude which is likely to be clinically significant. Measurement of baseline PImax and provision of RMT to at-risk individuals may reduce respiratory complications after tetraplegia.

TRIAL REGISTRATION NUMBER

Australian New Zealand Clinical Trials Registry (ACTRN 12612000929808).

Effects of Respiratory Muscle Training on Pulmonary Function in Individuals with Spinal Cord Injury: An Updated Meta-analysis

Objective

To investigate the pulmonary function responses to respiratory muscle training (RMT) in individuals with tetraplegia and provide a systematic review of the included studies.

Methods

Computerized retrieval of randomized controlled trials (RCT) in PubMed, Embase, and the Cochrane Library on the improvement of respiratory function in patients with spinal cord injury by RMT was conducted until May 2019. Two researchers independently screened the literature, extracted the data, and evaluated the risk of bias in the included studies. Articles were scored for their methodological quality using the Cochrane Collaboration risk of bias assessment tool.

Results

Sixteen studies were identified. A significant benefit of RMT was revealed for five outcomes: force vital capacity (FVC, WMD: -0.43, 95% CI -0.84 to -0.03, P = 0.037), vital capacity (VC, WMD: -0.40, 95% CI -0.69 to -0.12, P = 0.037), vital capacity (VC, WMD: -0.40, 95% CI -0.69 to -0.12, P = 0.037), vital capacity (VC, WMD: -0.40, 95% CI -0.69 to -0.12, P = 0.037), vital capacity (VC, WMD: -0.40, 95% CI -0.69 to -0.12, P = 0.037), vital capacity (VC, WMD: -0.40, 95% CI -0.69 to -0.12,

Conclusion

Our findings demonstrate that RMT can effectively improve spinal cord injury pulmonary function of the patient, which is marked by increasing respiratory strength, function, and endurance. Limited by the quantity and quality of the included studies, the above conclusion needs to be verified by more high-quality studies.

Supporting the need for community exercise programs: a case study

Introduction

Participation in exercise activities post spinal cord injury (SCI) can positively impact physical functioning and quality of life. Physically active individuals have improved functional performance compared with sedentary individuals with SCI. Consistent exercise interventions following SCI not only prompt neural recovery and offer myriad health benefits but they may also have persisting effects on functional abilities.

Case presentation

A 29-year-old male subject had a 15-year history of a C5-C6 AIS B SCI. The subject demonstrated improvements in the outcome measures and he reported enhanced ability to cough and to clear secretions, as well as an enhanced overall quality of life, after undergoing a 14-week course of Spinal Mobility training in combination with inspiratory muscle training (IMT). In addition to the Spinal Mobility training and IMT, he continued to partake in his normal exercise routine, which consisted of aerobic and strength training 3 days per week.

Discussion

This case reaffirms the benefits of consistent exercise training, in combination with IMT, for individuals with SCI. Community programs specifically targeted to individuals with SCI are needed. The subject's functional improvements demonstrate that incorporating Spinal Mobility training into a regular exercise routine may assist with functional gains in the chronic stage of SCI.

Improvement in Pulmonary Function with Short-term Rehabilitation Treatment in Spinal Cord Injury Patients

Cervical and upper thoracic spinal cord injury causes impairments in respiratory muscle performance, leading to variable degrees of pulmonary dysfunction and rendering deep breathing difficult for affected individuals. In this retrospective study, we investigated the effects of self-directed respiratory muscle training in this context by assessing pulmonary function relative to spinal cord injury characteristics. A total of 104 spinal cord injury patients (tetraplegia/paraplegia; 65/39, acute/subacute/chronic; 14/42/48) were admitted for short-term (4–8 weeks) in-patient clinical rehabilitation. Initial evaluation revealed a compromised pulmonary function with a percentage of predicted value of 62.0 and 57.5 in forced vital capacity in supine and forced vital capacity in sitting positions, respectively. Tetraplegic patients had more compromised pulmonary function compared with paraplegic patients. At follow-up evaluation, the percentage of predicted value of forced vital capacity in supine and sitting position improved overall on average by 11.7% and 12.7%, respectively. The peak cough flow improved by 22.7%. All assessed pulmonary function parameters improved significantly in all subgroups, with the greatest improvements found in patients with tetraplegia and subacute spinal cord injury. Therefore, short-term self-directed respiratory muscle training should be incorporated into all spinal cord injury rehabilitation regimens, especially for patients with tetraplegia and subacute spinal cord injury, as well as those with chronic spinal cord injury.

Respiratory muscle training in children and adults with neuromuscular disease

BACKGROUND

Neuromuscular diseases (NMDs) are a heterogeneous group of diseases affecting the anterior horn cell of spinal cord, neuromuscular junction, peripheral nerves and muscles. NMDs cause physical disability usually due to progressive loss of strength in limb muscles, and some NMDs also cause respiratory muscle weakness. Respiratory muscle training (RMT) might be expected to improve respiratory muscle weakness; however, the effects of RMT are still uncertain. This systematic review will synthesize the available trial evidence on the effectiveness and safety of RMT in people with NMD, to inform clinical practice.

OBJECTIVES

To assess the effects of respiratory muscle training (RMT) for neuromuscular disease (NMD) in adults and children, in comparison to sham training, no training, standard treatment, breathing exercises, or other intensities or types of RMT.

SEARCH METHODS

On 19 November 2018, we searched the Cochrane Neuromuscular Specialized Register, the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, and Embase. On 23 December 2018, we searched the US National Institutes for Health Clinical Trials Registry (ClinicalTrials.gov), the World Health Organization International Clinical Trials Registry Platform, and reference lists of the included studies.

SELECTION CRITERIA

We included randomized controlled trials (RCTs) and quasi-RCTs, including cross-over trials, of RMT in adults and children with a diagnosis of NMD of any degree of severity, who were living in the community, and who did not need mechanical ventilation. We compared trials of RMT (inspiratory muscle training (IMT) or expiratory muscle training (EMT), or both), with sham training, no training, standard treatment, different intensities of RMT, different types of RMT, or breathing exercises.

DATA COLLECTION AND ANALYSIS

We followed standard Cochrane methodological procedures.

MAIN RESULTS

We included 11 studies involving 250 randomized participants with NMDs: three trials (N = 88) in people with amyotrophic lateral sclerosis (ALS; motor neuron disease), six trials (N = 112) in Duchenne muscular dystrophy (DMD), one trial (N = 23) in people with Becker muscular dystrophy (BMD) or limb-girdle muscular dystrophy, and one trial (N = 27) in people with myasthenia gravis.Nine of the trials were at high risk of bias in at least one domain and many reported insufficient information for accurate assessment of the risk of bias. Populations, interventions, control interventions, and outcome measures were often different, which largely ruled out meta-analysis. All included studies assessed lung capacity, our primary outcome, but four did not provide data for analysis (1 in people with ALS and three cross-over studies in DMD). None provided long-term data (over a year) and only one trial, in ALS, provided information on adverse events. Unscheduled hospitalisations for chest infection or acute exacerbation of chronic respiratory failure were not reported and physical function and quality of life were reported in one (ALS) trial.Amyotrophic lateral sclerosis (ALS)Three trials compared RMT versus sham training in ALS. Short-term (8 weeks) effects of RMT on lung capacity in ALS showed no clear difference in the change of the per cent predicted forced vital capacity (FVC%) between EMT and sham EMT groups (mean difference (MD) 0.70, 95% confidence interval (CI) -8.48 to 9.88; N = 46; low-certainty evidence). The mean difference (MD) in FVC% after four months' treatment was 10.86% in favour of IMT (95% CI -4.25 to 25.97; 1 trial, N = 24; low-certainty evidence), which is larger than the minimal clinically important difference (MCID, as estimated in people with idiopathic pulmonary fibrosis). There was no clear difference between IMT and sham IMT groups, measured on the Amyotrophic Lateral Sclerosis Functional Rating Scale (ALFRS; range of possible scores 0 = best to 40 = worst) (MD 0.85, 95% CI -2.16 to 3.85; 1 trial, N = 24; low-certainty evidence) or quality of life, measured on the EuroQol-5D (0 = worst to 100 = best) (MD 0.77, 95% CI -17.09 to 18.62; 1 trial, N = 24; low-certainty evidence) over the medium term (4 months). One trial report stated that the IMT protocol had no adverse effect (very low-certainty evidence).Duchenne muscular dystrophy (DMD)Two DMD trials compared RMT versus sham training in young males with DMD. In one study, the mean post-intervention (6-week) total lung capacity (TLC) favoured RMT (MD 0.45 L, 95% CI -0.24 to 1.14; 1 trial, N = 16; low-certainty evidence). In the other trial there was no clear difference in post-intervention (18 days) FVC between RMT and sham RMT (MD 0.16 L, 95% CI -0.31 to 0.63; 1 trial, N = 20; low-certainty evidence). One RCT and three cross-over trials compared a form of RMT with no training in males with DMD; the cross-over trials did not provide suitable data. Post-intervention (6-month) values showed no clear difference between the RMT and no training groups in per cent predicted vital capacity (VC%) (MD 3.50, 95% CI -14.35 to 21.35; 1 trial, N = 30; low-certainty evidence).Becker or limb-girdle muscular dystrophyOne RCT (N = 21) compared 12 weeks of IMT with breathing exercises in people with Becker or limb-girdle muscular dystrophy. The evidence was of very low certainty and conclusions could not be drawn.Myasthenia gravisIn myasthenia gravis, there may be no clear difference between RMT and breathing exercises on measures of lung capacity, in the short term (TLC MD -0.20 L, 95% CI -1.07 to 0.67; 1 trial, N = 27; low-certainty evidence). Effects of RMT on quality of life are uncertain (1 trial; N = 27).Some trials reported effects of RMT on inspiratory and/or expiratory muscle strength; this evidence was also of low or very low certainty.

AUTHORS' CONCLUSIONS

RMT may improve lung capacity and respiratory muscle strength in some NMDs. In ALS there may not be any clinically meaningful effect of RMT on physical functioning or quality of life and it is uncertain whether it causes adverse effects. Due to clinical heterogeneity between the trials and the small number of participants included in the analysis, together with the risk of bias, these results must be interpreted very cautiously.

Development and validation of models to predict respiratory function in persons with long-term spinal cord injury

STUDY DESIGN

Multicenter, cross-sectional study.

OBJECTIVES

To validate previously developed respiratory function prediction models for persons with long-term spinal cord injury (SCI) and if necessary develop and validate new models.

SETTING

Ten SCI rehabilitation centers.

METHODS

Five respiratory function parameters were measured in adults with chronic, traumatic, motor complete SCI (C4-T12). First, the models published in 2012 were validated using Bland-Altman plots. Then, new models were calculated using 80% of the dataset by multiple regression analysis with the candidate predictors gender, age, height, weight, time post injury (TPI), lesion level, and smoking. In a third step, the new models were validated using the other 20% of the dataset by Bland-Altman plots.

RESULTS

In total 613 participants were included. For persons with long-term SCI, the 2012 models were poorly predictive, especially for respiratory muscle strength (R2 = 0.4). Significant predictors for all respiratory function parameters in the new models (R2 = 0.7-0.8) were lesion level, gender and weight. Small effects on single outcome parameters were observed for TPI and age whereas smoking had no effect. For the new models the mean differences between measured and predicted values for respiratory muscle strength were 4.0 ± 36.0 cm H₂O and for lung function parameters -0.5 ± 1.2 L (FVC), -0.3 ± 0.9 L (FEV1) and -0.5 ± 2.0 L/s (PEF).

CONCLUSION

We did not find better models for lung function in long-term SCI but those for respiratory muscle strength showed better accuracy.

SPONSORSHIP

The content of this publication was developed under grant from Wings for Life, grant number WFL-CH-017/14.

Inspiratory muscle training is feasible and safe for patients with acute spinal cord injury

OBJECTIVE

To investigate the feasibility and safety and, to a lesser extent efficacy, of inspiratory muscle training (IMT) for patients with acute complete cervical or thoracic spinal cord injury (SCI).

DESIGN

Prospective, observational pilot study comprising a series of case reports.

SETTING

Tertiary care, public hospital.

PARTICIPANTS

Seven adult subjects with an acute complete cervical or thoracic SCI.

INTERVENTIONS

Participants received IMT as soon as their respiratory condition was stable. A high-resistance, low-repetition program of IMT using a POWERbreathe KH1 device was instituted. Training comprised 3-6 sets of 6 breaths, commenced at 50% maximum inspiratory pressure with the training load progressively increased.

OUTCOME MEASURES

Feasibility (number of sessions when the criteria to participate in IMT were met/not met), safety (symptoms and physiological stability) before, during and after IMT sessions and efficacy (lung function) were measured.

RESULTS

There were 50 sessions in total where participants met the criteria to receive IMT, with a mean (range) of 7.1 (3-11) IMT sessions per participant delivered over 10.7 (4-17) days. IMT was feasible, with all 50 planned sessions of IMT able to be delivered, and safe, with stable physiological parameters and no adverse symptoms or events recorded before, during or after IMT. Maximal inspiratory pressure increased for four participants and forced vital capacity increased for three participants over the duration of their IMT sessions.

CONCLUSION

A high-resistance, low-repetition program of IMT was feasible and safe in adults with an acute complete cervical or thoracic SCI whose respiratory status was stable.

TRIAL REGISTRATION

Australian New Zealand Clinical Trials Registry (ACTRN 12614000975695).

Respiratory muscle training in individuals with spinal cord injury: effect of training intensity and -volume on improvements in respiratory muscle strength

STUDY DESIGN

Retrospective cohort study.

OBJECTIVES

To investigate the effect of training intensity and -volume on improvements in respiratory muscle strength in individuals with spinal cord injury (SCI).

SETTING

SCI rehabilitation center in Switzerland.

METHODS

Inpatients with SCI, lesion level C4-T12, who had at least 10 individualized inspiratory muscle training sessions with respiratory function measurements before and after the training period. Multiple regression analysis with natural logarithmic (ln) transformation of the outcome values was used to examine the effect of training intensity and -volume, lesion level and completeness, and baseline respiratory muscle strength on improvements in respiratory muscle strength.

RESULTS

Overall, 67 individuals were analyzed. Variation in PI_max was explained by PI_max at baseline and training intensity. This adjusted effect size suggested a 7% (95% CI 2.8 to 11.6%) increase in PI_max per 10 units of increase in training intensity. Controlling for the variation in baseline PE_max, the effect of training intensity on PE_max was conditional on AIS (p < 0.021). While individuals with motor complete lesions showed a 6.8% (95% CI 2.1 to 11.7%) increase in PE_max per 10 units of increase in training intensity, the corresponding adjusted effect size in those with motor incomplete lesions was 0.1% (95% CI -4.3 to 4.5%). The full models explained 57 and 60% of the variance of lnPI_max and lnPE_max, respectively.

CONCLUSION

The intensity of inspiratory muscle training was more relevant than training volume for the improvement of respiratory muscle strength in individuals with SCI. Thus, training intensity should be chosen as high as possible.

Effect of a respiratory muscle training program on lung function, respiratory muscle strength and resting oxygen consumption in sedentary young people

Introduction: Physical inactivity is a risk factor for developing noncommnunicable diseases, as well as respiratory and cardiovascular disorders. To counter this, different types of interventions have been proposed, including respiratory muscle training (RMT).Objective: To determine the effect of a respiratory muscle training program on respiratory muscle strength, lung function and resting oxygen consumption in sedentary subjects.Materials and methods: Pretest-posttest experimental study conducted in sedentary students. Lifestyle and the level of physical activity was determined using the International Physical Activity Questionnaire (IPAQ) and the FANTASTIC questionnaire, while respiratory muscle strength was established by means of expiratory and inspiratory pressure using a Dwyer Series 477 meter, and lung function and oxygen consumption was determined by spirometry and indirect calorimetry whit Vmax Encore 29C® calorimeter. Respiratory muscle training was performed for eight weeks with Threshold IMT system. R software, version 3.1.2, was used for statistical analysis.Results: Clinically and statistically significant improvements were found in maximal inspiratory pressure (MIP) (pre: 81.23±22.00/post: 96.44±24.54 cmH2O; p<0.001); maximal expiratory pressure (MEP) (pre: 94.84±21.63/post: 107.39±29.15 cmH2O; p<0.05); pulmonary function FEV1 [(pre: 3.33±0.88/post: 3.54±0.90L) (p<0.05)]; and FEV1/FVC ratio [(pre: 87.78±7.67/post: 93.20±6.02% (p<0.01)].Conclusion: The respiratory muscle training protocol implemented for eight weeks using the Threshold IMT system improved strength and FEV1. There were no significant changes in oxygen consumption.

Evaluation of a clinical implementation of a respiratory muscle training group during spinal cord injury rehabilitation

STUDY DESIGN

Retrospective cohort study.

OBJECTIVE

To evaluate the clinical implementation of a respiratory muscle training group during rehabilitation of individuals with spinal cord injury.

SETTING

Spinal cord injury rehabilitation center.

METHODS

Individuals with complete or incomplete lesions during inpatient rehabilitation, level C4-T12.Ten or more training sessions of either an inspiratory or a combined in- and expiratory muscle training were performed in a group setting with respiratory function measurements before and after the training period.

RESULTS

Analysis of 79 persons. Inspiratory muscle training was performed for 7 weeks with a median of 3.1 training sessions per week. Median training intensity was at 33% of baseline PImax and 58 repetitions were performed per training session. Respiratory mucle strength parameters improved by 18-68% of baseline values and lung function parameters by 11-31% after inspiratory muscle training.The combined respiratory muscle training was performed for 13 weeks with a median of 2.8 sessions per week and 88 repetitions per training session. Median inspiratory training resistance was at 39% of baseline PImax and median expiratory training resistance was at 27% of baseline PEmax. Respiratory muscle strength parameters improved by 14-51% of baseline values and lung function parameters improved by 15-34% after the combined in- and expiratory muscle training.

CONCLUSION

Respiratory resistance training improved respiratory function of individuals with acute spinal cord injury. Even if the combined respiratory muscle training was performed with more repetitions per training and nearly twice as long, relative improvements of respiratory function parameters were comparable with isolated inspiratory muscle training.

Effect of inspiratory muscle training (IMT) on aerobic capacity, respiratory muscle strength and rate of perceived exertion in paraplegics

Objectives: The purpose is to study the effect of inspiratory muscle training on aerobic capacity, respiratory muscle strength and rate of perceived exertion in paraplegics.Study Design: Randomized controlled trial.Settings: Rehabilitation department in Indian Spinal Injuries Centre, New Delhi.Participants: A sample of 30 paraplegics (T1-T12) were randomly allocated into two groups: inspiratory muscle training (IMT) group and control group.Interventions: The IMT group received inspiratory muscle training for 15 minutes 5 times a week for 4 weeks whereas the control group was given breathing exercises.Outcome measures: Maximal inspiratory pressure(MIP), maximal expiratory pressure (MEP), modified Borg's scale (MBS), 12 minute wheelchair aerobic test (12MWAT), multistage fitness test (MSFT), and 6 minutes push test (6MPT).Results: Out of 30 participants, 27 completed the study. The results show that after four weeks of IMT training, there were significant improvements in mean change scores of IMT group as compared to control group. Participants in IMT group performed better on 12MWAT (P = 0.001), MSFT (P = 0.001) and 6MPT (P = 0.001). Improvements in MIP scores (P = 0.001), MEP scores (P = 0.001) and MBS scores (P = 0.004) were also seen in IMT group.Conclusion: Both groups showed significant improvements, however inspiratory muscle training was seen to be more effective than deep breathing exercises for improving aerobic capacity, respiratory muscle strength and rate of perceived exertion in paraplegics.

Diaphragmatic Palsy

The diaphragm is the primary muscle of respiration, and its weakness can lead to respiratory failure. Diaphragmatic palsy can be caused by various causes. Injury to the phrenic nerve during thoracic surgeries is the most common cause for diaphragmatic palsy. Depending on the cause, the symptoms of diaphragmatic palsies vary from completely asymptomatic to disabling dyspnea requiring mechanical ventilation. On pulmonary function tests, there will be a decrease in the maximum respiratory muscle power. Spirometry shows reduced lung functions and a significant drop of lung function in supine position is typical of diaphragmatic palsy. Diaphragmatic movements with respiration can be directly visualized by fluoroscopic examination. Currently, this test is being replaced by bedside thoracic ultrasound examination, looking at the diaphragmic excursion with deep breathing or sniffing. This test is found to be equally efficient, and without risks of ionizing radiation of fluoroscope. Treatment of diaphragmatic palsy depends on the cause. Surgical approach of repair of diaphragm or nonsurgical approach of noninvasive ventilation has been tried with good success. Overall prognosis of diaphragmatic palsy is good, except when it is related to neuromuscular degeneration conditions.

Respiratory muscle training for multiple sclerosis

BACKGROUND

Multiple sclerosis (MS) is a chronic disease of the central nervous system, affecting approximately 2.5 million people worldwide. People with MS may experience limitations in muscular strength and endurance - including the respiratory muscles, affecting functional performance and exercise capacity. Respiratory muscle weakness can also lead to diminished performance on coughing, which may result in (aspiration) pneumonia or even acute ventilatory failure, complications that frequently cause death in MS. Training of the respiratory muscles might improve respiratory function and cough efficacy.

OBJECTIVES

To assess the effects of respiratory muscle training versus any other type of training or no training for respiratory muscle function, pulmonary function and clinical outcomes in people with MS.

SEARCH METHODS

We searched the Trials Register of the Cochrane Multiple Sclerosis and Rare Diseases of the Central Nervous System Group (3 February 2017), which contains trials from the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase, CINAHL, LILACS and the trial registry databases ClinicalTrials.gov and WHO International Clinical Trials Registry Platform. Two authors independently screened records yielded by the search, handsearched reference lists of review articles and primary studies, checked trial registers for protocols, and contacted experts in the field to identify further published or unpublished trials.

SELECTION CRITERIA

We included randomized controlled trials (RCTs) that investigated the efficacy of respiratory muscle training versus any control in people with MS.

DATA COLLECTION AND ANALYSIS

One reviewer extracted study characteristics and study data from included RCTs, and two other reviewers independently cross-checked all extracted data. Two review authors independently assessed risk of bias with the Cochrane 'Risk of bias' assessment tool. When at least two RCTs provided data for the same type of outcome, we performed meta-analyses. We assessed the certainty of the evidence according to the GRADE approach.

MAIN RESULTS

We included six RCTs, comprising 195 participants with MS. Two RCTs investigated inspiratory muscle training with a threshold device; three RCTs, expiratory muscle training with a threshold device; and one RCT, regular breathing exercises. Eighteen participants (˜ 10%) dropped out; trials reported no serious adverse events.We pooled and analyzed data of 5 trials (N=137) for both inspiratory and expiratory muscle training, using a fixed-effect model for all but one outcome. Compared to no active control, meta-analysis showed that inspiratory muscle training resulted in no significant difference in maximal inspiratory pressure (mean difference (MD) 6.50 cmH₂O, 95% confidence interval (CI) -7.39 to 20.38, P = 0.36, I² = 0%) or maximal expiratory pressure (MD -8.22 cmH₂O, 95% CI -26.20 to 9.77, P = 0.37, I² = 0%), but there was a significant benefit on the predicted maximal inspiratory pressure (MD 20.92 cmH₂O, 95% CI 6.03 to 35.81, P = 0.006, I² = 18%). Meta-analysis with a random-effects model failed to show a significant difference in predicted maximal expiratory pressure (MD 5.86 cmH₂O, 95% CI -10.63 to 22.35, P = 0.49, I² = 55%). These studies did not report outcomes for health-related quality of life.Three RCTS compared expiratory muscle training versus no active control or sham training. Under a fixed-effect model, meta-analysis failed to show a significant difference between groups with regard to maximal expiratory pressure (MD 8.33 cmH₂O, 95% CI -0.93 to 17.59, P = 0.18, I² = 42%) or maximal inspiratory pressure (MD 3.54 cmH₂O, 95% CI -5.04 to 12.12, P = 0.42, I² = 41%). One trial assessed quality of life, finding no differences between groups.For all predetermined secondary outcomes, such as forced expiratory volume, forced vital capacity and peak flow pooling was not possible. However, two trials on inspiratory muscle training assessed fatigue using the Fatigue Severity Scale (range of scores 0-56 ), finding no difference between groups (MD, -0.28 points, 95% CI-0.95 to 0.39, P = 0.42, I² = 0%). Due to the low number of studies included, we could not perform cumulative meta-analysis or subgroup analyses. It was not possible to perform a meta-analysis for adverse events, no serious adverse were mentioned in any of the included trials.The quality of evidence was low for all outcomes because of limitations in design and implementation as well as imprecision of results.

AUTHORS' CONCLUSIONS

This review provides low-quality evidence that resistive inspiratory muscle training with a resistive threshold device is moderately effective postintervention for improving predicted maximal inspiratory pressure in people with mild to moderate MS, whereas expiratory muscle training showed no significant effects. The sustainability of the favourable effect of inspiratory muscle training is unclear, as is the impact of the observed effects on quality of life.

Sleep Disordered Breathing and Spinal Cord Injury: Challenges and Opportunities

Purpose of review

This paper focuses on the sleep disorders in patients with spinal cord injury (SCI/D), particularly mechanism of sleep disordered breathing (SDB) and challenges in diagnosis and management. Based on a review of recent literatures and studies the paper summarizes some main challenges with respect to management of SDB in patients with SCI; and what are the responsible mechanisms of disease? What are the barriers in diagnosing and treating SDB using standard treatment such as positive airway pressure (CPAP)?.

Recent findings

Previous studies have shown that most SCI/D patients have SDB with heterogeneity in prevalence mainly related to using different definition or methods of diagnosing SDB, while recent studies using new definition of SDB based on recommended criteria from the American Academy of Sleep Medicine (AASM) and also include the data on effect of SCI/D level on prevalence and describe different type of SDB. Furthermore, recent data describes simplified method of diagnosing SDB by using a combination of home sleep apnea testing and transcutaneous CO2 monitoring. Finally, emerging data has been pointing at strong relationship between SDB and cardiovascular disease including nocturnal hypertension in patients with SCI/D.

Summary

The findings indicate that early testing for SDB and associated cardiovascular disease in patients with SCI is recommended and could be beneficial in reduced the high morbidity and mortality in this group of patients with disability. In addition, studies on treatment of other sleep disorders in SCI/D are not available to inform clinical decision making. Understanding the pathophysiology of sleep disorders in SCI/D is critical for the development of new effective therapies. This review provides evidence for best practices; highlights new discoveries for the diagnosis and management of sleep disorders in SCI/D, and discuss challenges and future directions.

Risk factors and the surgery affection of respiratory complication and its mortality after acute traumatic cervical spinal cord injury

The aim of this study is to estimate the risk factors of both respiratory complication (RC) and mortality after acute traumatic cervical spinal cord injury (TCSCI). Between July 2005 and July 2015, in 181 patients (142 males and 39 females; mean age 41.0 years) with acute TCSCI, we compared the difference and odds ratio in RC group (n = 73) with that of non-RC group (n = 108), and also death group (n = 15) and survival group (n = 166). We collected injury-related information after half a year of injury, which is as follows: the causes of injury, time of surgery, ICU (intensive care unit) days, ventilator days, ASIA (American Spinal Injury Association) classification, neurological injury, CIPS (Clinical Pulmonary Infection Score), and BMI (body mass index). Besides these, we gathered the general information such as age, gender, smoking history, and use of steroids. The study compared perioperative parameters; surgery-related and instrumentation- and graft-related complication rates; clinical parameters; patient satisfaction; and radiologic parameters. Variations like gender (odds ratio [OR] = 1.269, 95% confidence interval [CI] [0.609-2.646]), smoking history (OR = 2.902, 95% CI [1.564-5.385]), AIS grade (grade A) (OR = 6.439, 95% CI [3.334-12.434]), neurological level (C1-C4) (OR = 2.714, 95% CI [1.458-5.066]), and steroid use (OR = 2.983, 95% CI [1.276-6.969]) have a facilitated effect on RC. When we estimated surgery-related affection, only the time of surgery and anterior approach compared with posterior has significant difference in RC (P < .05). Between death and survival group, the aspect of age, non-surgical, CPIS, AIS grade, and BMI have statistically significant difference. Survival analysis reveals significant difference in aforementioned groups. In patients suffering from acute TCSCI, those who are old, have long smoking history, complete spinal cord injury, C1-C4, high CPIS, and fat have high incidence of RC and mortality.

Effects of Respiratory Training on Heart Rate Variability and Baroreflex Sensitivity in Individuals With Chronic Spinal Cord Injury

OBJECTIVE

To evaluate the effects of pressure threshold respiratory training (RT) on heart rate variability and baroreflex sensitivity in persons with chronic spinal cord injury (SCI).

DESIGN

Before-after intervention case-controlled clinical study.

SETTING

SCI research center and outpatient rehabilitation unit.

PARTICIPANTS

Participants (N=44) consisted of persons with chronic SCI ranging from C2 to T11 who participated in RT (n=24), and untrained control subjects with chronic SCI ranging from C2 to T9 (n=20).

INTERVENTIONS

A total of 21±2 RT sessions performed 5 days a week during a 4-week period using a combination of pressure threshold inspiratory and expiratory devices.

MAIN OUTCOME MEASURES

Forced vital capacity (FVC), forced expiratory volume in 1 second (FEV₁), and beat-to-beat arterial blood pressure and heart rate changes during the 5-second-long maximum expiratory pressure maneuver (5s MEP) and the sit-up orthostatic stress test, acquired before and after the RT program.

RESULTS

In contrast to the untrained controls, individuals in the RT group experienced significantly increased FVC and FEV₁ (both P<.01) in association with improved quality of sleep, cough, and speech. Sympathetically (phase II) and parasympathetically (phase IV) mediated baroreflex sensitivity both significantly (P<.05) increased during the 5s MEP. During the orthostatic stress test, improved autonomic control over heart rate was associated with significantly increased sympathetic and parasympathetic modulation (low- and high-frequency change: P<.01 and P<.05, respectively).

CONCLUSIONS

Inspiratory-expiratory pressure threshold RT is a promising technique to positively affect both respiratory and cardiovascular dysregulation observed in persons with chronic SCI.

Abdominal Binding Improves Neuromuscular Efficiency of the Human Diaphragm during Exercise

We tested the hypothesis that elastic binding of the abdomen (AB) would enhance neuromuscular efficiency of the human diaphragm during exercise. Twelve healthy non-obese men aged 24.8 ± 1.7 years (mean ± SE) completed a symptom-limited constant-load cycle endurance exercise test at 85% of their peak incremental power output with diaphragmatic electromyography (EMGdi) and respiratory pressure measurements under two randomly assigned conditions: unbound control (CTRL) and AB sufficient to increase end-expiratory gastric pressure (Pga,ee) by 5-8 cmH₂O at rest. By design, AB increased Pga,ee by 6.6 ± 0.6 cmH₂O at rest. Compared to CTRL, AB significantly increased the transdiaphragmatic pressure swing-to-EMGdi ratio by 85-95% during exercise, reflecting enhanced neuromuscular efficiency of the diaphragm. By contrast, AB had no effect on spirometric parameters at rest, exercise endurance time or an effect on cardiac, metabolic, ventilatory, breathing pattern, dynamic operating lung volume, and perceptual responses during exercise. In conclusion, AB was associated with isolated and acute improvements in neuromuscular efficiency of the diaphragm during exercise in healthy men. The implications of our results are that AB may be an effective means of enhancing neuromuscular efficiency of the diaphragm in clinical populations with diaphragmatic weakness/dysfunction.

Diaphragm Dysfunction: Diagnostic Approaches and Management Strategies

The diaphragm is the main inspiratory muscle, and its dysfunction can lead to significant adverse clinical consequences. The aim of this review is to provide clinicians with an overview of the main causes of uni- and bi-lateral diaphragm dysfunction, explore the clinical and physiological consequences of the disease on lung function, exercise physiology and sleep and review the available diagnostic tools used in the evaluation of diaphragm function. A particular emphasis is placed on the clinical significance of diaphragm weakness in the intensive care unit setting and the use of ultrasound to evaluate diaphragmatic action.

Respiratory problems and management in people with spinal cord injury

Spinal cord injury (SCI) is characterised by profound respiratory compromise secondary to the level of loss of motor, sensory and autonomic control associated with the injury. This review aims to detail these anatomical and physiological changes after SCI, and outline their impact on respiratory function. Injury-related impairments in strength substantially alter pulmonary mechanics, which in turn affect respiratory management and care. Options for treatments must therefore be considered in light of these limitations.

KEY POINTS

Respiratory impairment following spinal cord injury (SCI) is more severe in high cervical injuries, and is characterised by low lung volumes and a weak cough secondary to respiratory muscle weakness.Autonomic dysfunction and early-onset sleep disordered breathing compound this respiratory compromise.The mainstays of management following acute high cervical SCI are tracheostomy and ventilation, with noninvasive ventilation and assisted coughing techniques being important in lower cervical and thoracic level injuries.Prompt investigation to ascertain the extent of the SCI and associated injuries, and appropriate subsequent management are important to improve outcomes.

EDUCATIONAL AIMS

To describe the anatomical and physiological changes after SCI and their impact on respiratory function.To describe the changes in respiratory mechanics seen in cervical SCI and how these changes affect treatments.To discuss the relationship between injury level and respiratory compromise following SCI, and describe those at increased risk of respiratory complications.To present the current treatment options available and their supporting evidence.

Practical Recommendations for Diagnosis and Management of Respiratory Muscle Weakness in Late-Onset Pompe Disease

Pompe disease is an autosomal-recessive lysosomal storage disorder characterized by progressive myopathy with proximal muscle weakness, respiratory muscle dysfunction, and cardiomyopathy (in infants only). In patients with juvenile or adult disease onset, respiratory muscle weakness may decline more rapidly than overall neurological disability. Sleep-disordered breathing, daytime hypercapnia, and the need for nocturnal ventilation eventually evolve in most patients. Additionally, respiratory muscle weakness leads to decreased cough and impaired airway clearance, increasing the risk of acute respiratory illness. Progressive respiratory muscle weakness is a major cause of morbidity and mortality in late-onset Pompe disease even if enzyme replacement therapy has been established. Practical knowledge of how to detect, monitor and manage respiratory muscle involvement is crucial for optimal patient care. A multidisciplinary approach combining the expertise of neurologists, pulmonologists, and intensive care specialists is needed. Based on the authors' own experience in over 200 patients, this article conveys expert recommendations for the diagnosis and management of respiratory muscle weakness and its sequelae in late-onset Pompe disease.

Respiratory Training Improves Blood Pressure Regulation in Individuals With Chronic Spinal Cord Injury

OBJECTIVE

To investigate the effects of respiratory motor training (RMT) on pulmonary function and orthostatic stress-mediated cardiovascular and autonomic responses in individuals with chronic spinal cord injury (SCI).

DESIGN

Before-after intervention case-controlled clinical study.

SETTING

SCI research center and outpatient rehabilitation unit.

PARTICIPANTS

A sample of (N=21) individuals with chronic SCI ranging from C3 to T2 diagnosed with orthostatic hypotension (OH) (n=11) and healthy, noninjured controls (n=10).

INTERVENTIONS

A total of 21±2 sessions of pressure threshold inspiratory-expiratory RMT performed 5d/wk during a 1-month period.

MAIN OUTCOME MEASURES

Standard pulmonary function test: forced vital capacity, forced expiratory volume in one second, maximal inspiratory pressure, maximal expiratory pressure, beat-to-beat arterial blood pressure, heart rate, and respiratory rate were acquired during the orthostatic sit-up stress test before and after the RMT program.

RESULTS

Completion of RMT intervention abolished OH in 7 of 11 individuals. Forced vital capacity, low-frequency component of power spectral density of blood pressure and heart rate oscillations, baroreflex effectiveness, and cross-correlations between blood pressure, heart rate, and respiratory rate during the orthostatic challenge were significantly improved, approaching levels observed in noninjured individuals. These findings indicate increased sympathetic activation and baroreflex effectiveness in association with improved respiratory-cardiovascular interactions in response to the sudden decrease in blood pressure.

CONCLUSIONS

Respiratory training increases respiratory capacity and improves orthostatic stress-mediated respiratory, cardiovascular, and autonomic responses, suggesting that this intervention can be an efficacious therapy for managing OH after SCI.